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Sample records for mammalian ventricular myocardium

  1. Backscatter and attenuation characterization of ventricular myocardium

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    Gibson, Allyson Ann

    2009-12-01

    This Dissertation presents quantitative ultrasonic measurements of the myocardium in fetal hearts and adult human hearts with the goal of studying the physics of sound waves incident upon anisotropic and inhomogeneous materials. Ultrasound has been used as a clinical tool to assess heart structure and function for several decades. The clinical usefulness of this noninvasive approach has grown with our understanding of the physical mechanisms underlying the interaction of ultrasonic waves with the myocardium. In this Dissertation, integrated backscatter and attenuation analyses were performed on midgestational fetal hearts to assess potential differences in the left and right ventricular myocardium. The hearts were interrogated using a 50 MHz transducer that enabled finer spatial resolution than could be achieved at more typical clinical frequencies. Ultrasonic data analyses demonstrated different patterns and relative levels of backscatter and attenuation from the myocardium of the left ventricle and the right ventricle. Ultrasonic data of adult human hearts were acquired with a clinical imaging system and quantified by their magnitude and time delay of cyclic variation of myocardial backscatter. The results were analyzing using Bayes Classification and ROC analysis to quantify potential advantages of using a combination of two features of cyclic variation of myocardial backscatter over using only one or the other feature to distinguish between groups of subjects. When the subjects were classified based on hemoglobin A1c, the homeostasis model assessment of insulin resistance, and the ratio of triglyceride to high-density lipoprotein-cholesterol, differences in the magnitude and normalized time delay of cyclic variation of myocardial backscatter were observed. The cyclic variation results also suggested a trend toward a larger area under the ROC curve when information from magnitude and time delay of cyclic variation is combined using Bayes classification than when

  2. The helical ventricular myocardial band: global, three-dimensional, functional architecture of the ventricular myocardium.

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    Kocica, Mladen J; Corno, Antonio F; Carreras-Costa, Francesc; Ballester-Rodes, Manel; Moghbel, Mark C; Cueva, Clotario N C; Lackovic, Vesna; Kanjuh, Vladimir I; Torrent-Guasp, Francisco

    2006-04-01

    We are currently witnessing the advent of new diagnostic tools and therapies for heart diseases, but, without serious scientific consensus on fundamental questions about normal and diseased heart structure and function. During the last decade, three successive, international, multidisciplinary symposia were organized in order to setup fundamental research principles, which would allow us to make a significant step forward in understanding heart structure and function. Helical ventricular myocardial band of Torrent-Guasp is the revolutionary new concept in understanding global, three-dimensional, functional architecture of the ventricular myocardium. This concept defines the principal, cumulative vectors, integrating the tissue architecture (i.e. form) and net forces developed (i.e. function) within the ventricular mass. Here we expose the compendium of Torrent-Guasp's half-century long functional anatomical investigations in the light of ongoing efforts to define the integrative approach, which would lead to new understanding of the ventricular form and function by linking across multiple scales of biological organization, as defined in ongoing Physiome project. Helical ventricular myocardial band of Torrent-Guasp may also, hopefully, allow overcoming some difficulties encountered in contemporary efforts to create a comprehensive mathematical model of the heart.

  3. MRI in the diagnosis of non-compacted ventricular Myocardium (NCVM) compared to echocardiography

    International Nuclear Information System (INIS)

    Weiss, F.; Habermann, C.R.; Sievers, J.; Weil, J.; Adam, G.; Lilje, C.; Razek, W.

    2003-01-01

    Purpose: To report the detection of con-compacted ventricular myocardium (NVCM) with MRI compared to echocardiography in 8 patients. Material and methods: Non-compaction of the ventricular myocardium is a congenital disorder characterized by an altered structure of the myocardial wall resulting from an intrauterine arrest in endomyocardial embryogenesis. The morphological findings consist of a prominent meshwork of multiple myocardial trabeculations and deep intertrabecular recesses, communicating with the left ventricular cavity. 8 consecutive patients (mean age 7.3 years) with clinical and echocardiographic signs of NCVM were examined by MRI (1.5 T, Vision, Siemens) in short axis and 2- and 4-chamber views, using T 1 -weighted TSE and Cine-GRE in 6 patients and true FISP sequences in 2 patients. MRI and echocardiography were evaluated for visibility, signs of NCVM and involvement of myocardial wall segments. Thickness was measured for non-compacted and compacted myocardium and the non-compacted to compacted (N/C) ratio calculated. Results: MRI diagnosed 6 of 8 patients of having NCVM. Myocardial thickness as measured by echocardiography and MRI showed a good correlation in compacted myocardium (r = 0.82) and no correlation in non-compacted myocardium (r = 0.4). In 2 cases, non-compacted myocardium was detected, but echocardiography did not reach the N/C ratio > 2 as required to diagnose NCVM in accordance with the criteria found in the literature. Both patients were also misdiagnosed by MRI performed with Cine-GRE. MRI reached a N/C ratio > 2 in only three patients. Newer TruFisp sequences showed no definite advantages. Extent of non-compaction could be visualized correctly with MRI. (orig.) [de

  4. The Histological Effects of L-arginine on Ventricular Myocardium in Iron Treated Male Rats

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    M Sofiabadi

    2012-05-01

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    Background and Objectives: Iron overload is detrimental for the body and can create damage to different body tissues, such as myocardium by producing oxidative stress. Therefore, the antioxidant factors can neutralize iron induced damages. According to available reports, L-arginine as a precursor nitric oxide production has antioxidant effects. This study was carried out to evaluate the histological effects of iron overload on ventricular muscle and preventive role of L-arginine in male rats.
    Methods: In this experiment, 40 male rats with weight range of 300-250g were divided at random into five equal groups including:1- Control, 2- Iron (10mg/kg, ip, 3- Iron(10mg/kg, ip+L-arginine (1mg/ml, po, 4- Iron (50mg/kg, ip and 5- Iron (50mg/kg,ip+L-arginine(1mg/ml,po. After treatment (6 weeks, the animals were anesthetized and the samples of left apical ventricular myocardium were taken out and morphological studies were done following fixation with 10% formalin and H&E staining. Microscopic parameters under study were cell swelling, vessel dilatation and hypercongestion, cell necrosis and tissue deformity. The type and severity of damage to the tissue were also noted. Data were analyzed using chi-square statistical procedure, and Pvalue≤0.05 were considered to be significant. 
    Results: The data showed moderate changes in the ventricular myocardium of group 2 that was significant in comparison to the control group (P<0.05. The ventricular myocardium of group 3 showed low changes and wasn't significant in comparison to control group (P=0.84. The ventricular myocardium of the group 4 showed severe changes in comparison to the control group (P<0.01. The low change showed in the ventricular myocardium of group 5 that wasn't significant in comparison to the control group.

    Conclusion: This study showed

  5. Effects of hydroxyl radical induced-Injury in atrial versus ventricular myocardium of dog and rabbit

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    Nitisha Hiranandani

    2010-09-01

    Full Text Available Aim: Despite the widespread use of ventricular tissue in the investigation involving hydroxyl-radical (OH* injury, one of the most potent mediators in ischemia-reperfusion injury, little is known about the impact on atrial myocardium. In this study we thus compared the OH*-induced injury response between atrial and right ventricular muscles from both rabbits and dogs under identical experimental conditions. Methods: Small, contracting ventricular and atrial rabbit and dog trabeculae were directly exposed to OH*, and contractile properties were examined and quantified. Results: A brief OH* exposure led to transient rigor like contracture with marked elevation of diastolic tension and depression of developed force. Although the injury response showed similarities between atrial and ventricular myocardium, there were significant differences as well. In rabbit atrial muscles, the development of the contracture and its peak was much faster as compared to ventricular muscles. Also, at the peak of contracture, both rabbit and dog atrial muscles show a lesser degree of contractile dysfunction. Conclusion: These results indicate that both atrial and ventricular muscles develop a rigor like contracture after acute OH*-induced injury, and atrial muscles showed a lesser degree of contractile dysfunction. Comparison of dog versus rabbit tissue shows that the response was similar in magnitude, but slower to develop in dog tissue.

  6. Comparative study between MRI and echocardiography in noncompaction of ventricular myocardium

    International Nuclear Information System (INIS)

    Sun Ziyan; Xia Liming; Wang Chengyuan; Rao Jingjing; Shenyu Weihui

    2007-01-01

    Objective: To investigate the MRI and echocardiography manifestations of noncompaction of ventricular myocardium(NVM) and assess the role of MR1 in the diagnosis of NVM by comparing it with echocardiography. Methods: Fourteen cases of NVM diagnosed by echocardiography were examined with MRI, including scanning of black-blood sequences, double inversion recovery fast spin echo (DIBFSE) and triple inversion recovery fast spin echo (TIRFSE), and white blood sequence: fast imaging employ steady state acquisition (FIESTA). Scanning plane includes short axis view, four-chamber view and long axis view. Results: Both MRI and echocardiography displayed involvement of left ventricles in thirteen cases and involvement of double ventricles in one case. Apexes of heart and the intermedius are commonly affected. MRI showed 54 segments and echocardiography showed 53 segments affected, and there is no significant difference between the capability of MRI and echocardiography (P=1,000). The affected myocardium consisted of two layers: subendocardial noncompacted myocardium and epicardial compacted myocardium, and the ratio measurement of N/C by MRI was 3.37±0.89 and it was 3.19±0.82 by echocardiography. Noncompacted myocardium was characterized by prominent and excessive myocardial trabeculations and deep intratrabecular recesses, in which the blood flow was communicated with the ventricle. One case was complicated with ventricular aneurysm, and coronary arteriography was performed with unremarkable findings. One case underwent heart transplantation because of progressive heart failure, Gross findings demonstrated prominent muscular' trabeculations with deep intratrabecular recesses, which coincided well with MRI findings. Conclusion: The MRI manifestation of NVM is characteristic, and MRI with multiple series and planes is helpful in the diagnose of NVM. Compared with echocardiography, MRI could display the pathological cardiac muscle more clearly, because of its high soft

  7. Factors of Formation of Various Types of Left Ventricular Diastolic Filling in Adolescents with Myocardium Pathology

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    L.F. Bogmat

    2016-08-01

    Full Text Available Objective: to study the main components of the formation of impaired left ventricular diastolic filling in adolescents with myocardial pathology. Materials and methods. The study involved 110 adolescents with myocardial pathology aged 13–18 years, of which 40 — with heart rhythm disorder, 40 — with dysplastic cardiomyopathy, 30 — with primary hypertension. Morphological and functional parameters of the heart were studied using ultrasound according to standard procedure. Left ventricular diastolic function has been studied in the pulsed wave Doppler mode with transmitral flow mapping from the apical access of four-chambered heart. For an adequate assessment of left ventricular diastolic function and detection of its earliest disorders, adolescents underwent tests with isometric exercise. Based on these results, adolescents were divided in terms of the E/A ratio. In order to identify common latent factors that explain the correlation between indicators, we have used the factor analysis, namely, the principal component analysis. All statistical procedures were performed using application packages Statgraphics Centurion. Results. On the initial stages of formation of diastolic dysfunction of the left ventricular myocardium in adolescents, a significant role is played by a number of factors, which can be conditionally defined as the geometric, functional and neurohumoral factors consistently included in the pathological process. Thus, during the formation of left ventricular diastolic dysfunction type 1, the number one is neurohumoral factor, namely, the activation of the sympathoadrenal system, then peripheral vascular tone is being involved in the pathological process, and, consequently, a geometric factor — changing the sizes of the left atrium. In the formation of left ventricular diastolic dysfunction type 2, the process consistently involves the renin-angiotensin system, namely, renin, a functional factor is presented by the indices

  8. Characterization of the functional and anatomical differences in the atrial and ventricular myocardium from three species of elasmobranch fishes

    DEFF Research Database (Denmark)

    Larsen, Julie; Bushnell, Peter; Steffensen, John

    2017-01-01

    We assessed the functional properties in atrial and ventricular myocardium (using isolated cardiac strips) of smooth dogfish (Mustelus canis), clearnose skate (Raja eglanteria), and sandbar shark (Carcharhinus plumbeus) by blocking Ca2+ release from the sarcoplasmic reticulum (SR) with ryanodine...... positive first derivative (i.e., contractility), and increased time to 50 % relaxation in atrial tissue from smooth dogfish at 30 °C. It also increased times to peak force and half relaxation in clearnose skate atrial and ventricular tissue at both temperatures, but only in atrial tissue from sandbar shark...... at 30 °C; indicating that SR involvement in excitation–contraction (EC) coupling is species- and temperature-specific in elasmobranch fishes, as it is in teleost fishes. Atrial and ventricular myocardium from all three species displayed a negative force–frequency relationship, but there was no evidence...

  9. Change of short-term memory effect in acute ischemic ventricular myocardium: a computational study.

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    Mei, Xi; Wang, Jing; Zhang, Hong; Liu, Zhi-cheng; Zhang, Zhen-xi

    2014-02-01

    The ionic mechanism of change in short-term memory (STM) during acute myocardial ischemia has not been well understood. In this paper, an advanced guinea pig ventricular model developed by Luo and Rudy was used to investigate STM property of ischemic ventricular myocardium. STM response was calculated by testing the time to reach steady-state action potential duration (APD) after an abrupt shortening of basic cycling length (BCL) in the pacing protocol. Electrical restitution curves (RCs), which can simultaneously visualize multiple aspects of APD restitution and STM, were obtained from dynamic and local S1S2 restitution portrait (RP), which consist of a longer interval stimulus (S1) and a shorter interval stimulus (S2). The angle between dynamic RC and local S1S2 RC reflects the amount of STM. Our results indicated that compared with control (normal) condition, time constant of STM response in the ischemic condition decreased significantly. Meanwhile the angle which reflects STM amount is less in ischemic model than that in control model. By tracking the effect of ischemia on intracellular ion concentration and membrane currents, we declared that changes in membrane currents caused by ischemia exert subtle influences on STM; it is only the decline of intracellular calcium concentration that give rise to the most decrement of STM. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  10. Role of the Purkinje-Muscle Junction on the Ventricular Repolarization Heterogeneity in the Healthy and Ischemic Ovine Ventricular Myocardium

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    Marine E. Martinez

    2018-06-01

    Full Text Available Alteration of action potential duration (APD heterogeneity contributes to arrhythmogenesis. Purkinje-muscle junctions (PMJs present differential electrophysiological properties including longer APD. The goal of this study was to determine if Purkinje-related or myocardial focal activation modulates ventricular repolarization differentially in healthy and ischemic myocardium. Simultaneous epicardial (EPI and endocardial (ENDO optical mapping was performed on sheep left ventricular (LV wedges with intact free-running Purkinje network (N = 7. Preparations were paced on either ENDO or EPI surfaces, or the free-running Purkinje fibers (PFs, mimicking normal activation. EPI and ENDO APDs were assessed for each pacing configuration, before and after (7 min of the onset of no-flow ischemia. Experiments were supported by simulations. In control conditions, maximal APD was found at endocardial PMJ sites. We observed a significant transmural APD gradient for PF pacing with PMJ APD = 347 ± 41 ms and EPI APD = 273 ± 36 ms (p < 0.001. A similar transmural gradient was observed when pacing ENDO (49 ± 31 ms; p = 0.005. However, the gradient was reduced when pacing EPI (37 ± 20 ms; p = 0.005. Global dispersion of repolarization was the most pronounced for EPI pacing. In ischemia, both ENDO and EPI APD were reduced (p = 0.005 and the transmural APD gradient (109 ± 55 ms was increased when pacing ENDO compared to control condition or when pacing EPI (p < 0.05. APD maxima remained localized at functional PMJs during ischemia. Local repolarization dispersion was significantly higher at the PMJ than at other sites. The results were consistent with simulations. We found that the activation sequence modulates repolarization heterogeneity in the ischemic sheep LV. PMJs remain active following ischemia and exert significant influence on local repolarization patterns.

  11. The effect of percutaneous transmyocardial laser revascularization on left ventricular function in a porcine model of hibernating myocardium

    International Nuclear Information System (INIS)

    Almeda, Francis Q.; Glock, Dana; Sandelski, Joanne; Ibrahim, Osama; Macioch, James E.; Allen, Trisha; Dainauskas, John R.; Parrillo, Joseph E.; Snell, R. Jeffrey; Schaer, Gary L.

    2004-01-01

    Background: Hibernating myocardium is defined as a state of persistently impaired myocardial function at rest due to reduced coronary blood flow that can partially or completely be restored to normal if the myocardial oxygen supply/demand relationship is favorably altered. Percutaneous laser revascularization (PMR) is an emerging catheter-based technique that involves creating channels in the myocardium, directly through a percutaneous approach with a laser delivery system, and has been shown to reduce symptoms in patients with severe refractory angina; however, its effect on improving regional wall motion abnormalities in hibernating myocardium has not been clearly established. We sought to determine the effect of PMR using the Eclipse System (Cardiogenesis) on left ventricular function in a porcine model of hibernating myocardium. Methods: A model of hibernating myocardium was created by placement of an ameroid constrictor in the proximal left anterior descending artery of a 35 kg male Yorkshire pig. The presence of hibernating myocardium was confirmed with dobutamine stress echocardiography (DSE) and defined as severe hypocontractility at rest, with an improvement in systolic wall thickening with low-dose dobutamine in myocardial regions with a subsequent deterioration in function at peak stress (biphasic response). After the demonstration of hibernating myocardium, PMR was performed in the area of hypocontractile function, and the serial echocardiography was performed. The echocardiograms were reviewed by an experienced echocardiologist blinded to the results, and regional wall motion was assessed using the American Society of Echocardiography Wall Motion Score. Six weeks after PMR, the animal was sacrificed and the heart sent for histopathologic studies. Results: A comparison of the regional wall motion function of the area distal to the ameroid constrictor and in the contralateral wall at baseline, post-ameroid placement, and post-PMR was performed

  12. Multivariate prediction of spontaneous repetitive responses in ventricular myocardium exposed in vitro to simulated ischemic conditions.

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    Schiariti, M; Puddu, P E; Rouet, R

    1994-06-01

    Guinea-pig ventricular myocardium was partly exposed to normal Tyrode's superfusion and partly to altered conditions (using modified Tyrode's solution) set to simulate acute myocardial ischemia (PO2 80 +/- 10 mmHg; no glucose; pH 7.00 +/- 0.05; K+ 12 mM). Using a double-chamber tissue bath and standard microelectrode technique, the occurrence of spontaneous repetitive responses was investigated during simulated ischemia (occlusion) and after reperfusing the previously ischemic superfused tissue with normal Tyrode's solution (reperfusion). In 62 experiments (42 animals) the effects of: (1) duration of simulated ischemia (1321 +/- 435 s), (2) stimulation rate (1002 +/- 549 ms) and (3) number of successive simulated ischemic periods (occlusions) (1.58 +/- 0.92) on: (1) resting membrane potential, (2) action potential amplitude, (3) duration of 50 and 90% action potentials and (4) maximal upstroke velocity of action potential were studied. All variables were considered as gradients (delta) between normal and ischemic tissue. Both during occlusion and upon reperfusion, spontaneous repetitive responses were coded as single, couplets, salvos (three to nine and > 10) or total spontaneous repetitive responses (coded present when at least one of the above-mentioned types was seen). The incidence of total spontaneous repetitive responses was 31% (19/62) on occlusion and 85% (53/62) upon reperfusion. Cox's models (forced and stepwise) were used to predict multivariately the occurrence of arrhythmic events considered as both total spontaneous repetitive responses and as separate entities. These models were applicable since continuous monitoring of the experiments enabled exact timing of spontaneous repetitive response onset during both occlusion and reperfusion. In predicting reperfusion spontaneous repetitive responses, total spontaneous repetitive responses and blocks observed during the occlusion period were also considered. Total occlusion spontaneous repetitive responses

  13. Peculiarities of cardiac hemodynamics and functional state of left ventricular myocardium in teenagers with connective heart tissue dysplasia

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    Makhmudova F.M.

    2011-03-01

    Full Text Available The aim of investigation is to study heart hemodynamics in teenagers with connective tissue dysplasia of heart (CTDH. 35 patients ages 12 to 15 years with CTDH have been observed: Group I (n=14 are the patients with mitral valve prolapse (MVP without mitral regurgitation (MR and myxomatous degeneration(MD or isolated minor heart abnormalities (MHA, Group II (n=11are patients with MVP and MR in combination with 1 or2 MHA, and Group III (n=10 are patients with MVP and mixoid degeneration (MD in combination with 2 or more MHA. The control group consisted of 15 patients of the same age without MHA. All the children passed Doppler and echocardiography. According to the results significant changes of cardiohemodynamic indices in patients of Group I were not observed. The changes of size and volume indices of the left ventricle (LV, increase in wall thickness and diastolic dysfunction of the LV were observed in Group II. The significant changes of systolic function of left ventricular myocardium were observed in Group III. The study comes to the conclusion that teenagers with CTDH have definite changes of heart hemodynamics and functional state of left ventricular myocardium. These changes depend on mitral regurgitation, myxomatous degeneration and MHA combination

  14. Assessment of 123I-β-methyl iodophenyl pentadecanoic acid (BMIPP) myocardial scintigraphy in patients of chronic right ventricular overload. Fatty acid metabolism in right ventricular myocardium

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    Mutoh, Hiroshi

    1997-01-01

    An investigation on the right ventricular pressure level and the abnormalities in the fatty acid metabolism of myocardium was made using 123 I-βmethyl-iodophenyl pentadecanoic acid (BMIPP) myocardial SPECT in patients with chronic right ventricular overloading. Twenty patients who presented with right ventricular systolic pressure (RVSP) of 35 mmHg or more were used as the subjects. Dual myocardial SPECT with 201 TlCl (Tl) and BMIPP was carried out for the subjects and RVc/LVc, a ratio of radioactivity count incorporated in the right ventricular free wall to the left one was determined for Tl and BMIPP. And the correlations between RVc/LVc and RVSP, and RVc/LVc and RVSP/LVSP were examined. The subjects were classified into 3 groups based on the RVSP levels and the count ratio, BMIPP/Tl was compared among the three groups. With respect of Tl uptake, there were significant, positive correlations between RVc/LVc and RVSP (correlation coefficient r=0.51, p<0.05) and between RVc/LVc and RVSP/LVSP (correlation coefficient r=0.59, p<0.01). On the other hand, no significant correlation was found between them with respect of the uptake of BMIPP. The BMIPP/Tl ratio in the group with higher than 80 mmHg of RVSP was 0.82±0.06, which was significantly lower than the ratio's for two groups of less than 80 mmHg; 0.91±0.07 and 0.98±0.04 in the group with 35-49 and 50-79 mmHg of RVSP, respectively. These results show that when compared with BMIPP, Tl is superior for the estimation of right ventricular pressure. For the patients with right ventricular overloading, it was suggested that when RVSP reaches 80 mmHg or more, there appear some disorders in the fatty acid metabolism in the right ventricular myocardium. (author)

  15. Mr 40,000 and Mr 39,000 pertussis toxin substrates are increased in surgically denervated dog ventricular myocardium

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    Hershberger, R.E.; Feldman, A.M.; Anderson, F.L.; Kimball, J.A.; Wynn, J.R.; Bristow, M.R. (Univ. of Utah School of Medicine, Salt Lake City (USA))

    1991-04-01

    To test the general hypothesis that cardiac innervation may participate in myocardial G protein regulation, we examined the effects of complete intrapericardial surgical denervation or sham operation in dogs. In particulate fractions of dog left ventricular (LV) myocardium harvested 28-33 days after denervation or sham operation, Mr 40,000 and Mr 39,000 pertussis toxin-sensitive substrates (G proteins) were increased by 31% (1.31 +/- 0.084 vs 1.00 +/- 0.058 OD, arbitrary units, p less than 0.01) and 40% (1.40 +/- 0.117 vs. 1.000 +/- 0.084 OD, arbitrary units, p less than 0.02), respectively, as compared with sham-operated controls. The Mr 40,000 pertussis toxin-sensitive band comigrated with a pertussis toxin-sensitive substrate in human erythrocyte membranes known to contain an alpha Gi species. In these same preparations basal, GTP and GppNHp stimulated adenylate cyclase activities were decreased in denervated heart by 20, 26, and 19%, respectively, consistent with increased activity of an inhibitory G protein. In contrast, Gs function was not altered, because cyc(-) membranes reconstituted with membrane extracts and fluoride and beta-receptor-stimulated adenylate cyclase activity were not different between groups. Furthermore, adenylate cyclase catalytic subunit function as assessed with forskolin and manganese stimulation was not different between preparations of control and denervated heart. We conclude that in preparations of surgically denervated dog myocardium Mr 40,000 and Mr 39,000 pertussis toxin-sensitive G proteins are increased by 31 and 40%, respectively, and that functional alterations in adenylate cyclase activity exist, consistent with increased inhibitory G-protein function.

  16. Mr 40,000 and Mr 39,000 pertussis toxin substrates are increased in surgically denervated dog ventricular myocardium

    International Nuclear Information System (INIS)

    Hershberger, R.E.; Feldman, A.M.; Anderson, F.L.; Kimball, J.A.; Wynn, J.R.; Bristow, M.R.

    1991-01-01

    To test the general hypothesis that cardiac innervation may participate in myocardial G protein regulation, we examined the effects of complete intrapericardial surgical denervation or sham operation in dogs. In particulate fractions of dog left ventricular (LV) myocardium harvested 28-33 days after denervation or sham operation, Mr 40,000 and Mr 39,000 pertussis toxin-sensitive substrates (G proteins) were increased by 31% (1.31 +/- 0.084 vs 1.00 +/- 0.058 OD, arbitrary units, p less than 0.01) and 40% (1.40 +/- 0.117 vs. 1.000 +/- 0.084 OD, arbitrary units, p less than 0.02), respectively, as compared with sham-operated controls. The Mr 40,000 pertussis toxin-sensitive band comigrated with a pertussis toxin-sensitive substrate in human erythrocyte membranes known to contain an alpha Gi species. In these same preparations basal, GTP and GppNHp stimulated adenylate cyclase activities were decreased in denervated heart by 20, 26, and 19%, respectively, consistent with increased activity of an inhibitory G protein. In contrast, Gs function was not altered, because cyc(-) membranes reconstituted with membrane extracts and fluoride and beta-receptor-stimulated adenylate cyclase activity were not different between groups. Furthermore, adenylate cyclase catalytic subunit function as assessed with forskolin and manganese stimulation was not different between preparations of control and denervated heart. We conclude that in preparations of surgically denervated dog myocardium Mr 40,000 and Mr 39,000 pertussis toxin-sensitive G proteins are increased by 31 and 40%, respectively, and that functional alterations in adenylate cyclase activity exist, consistent with increased inhibitory G-protein function

  17. Native T1 value in the remote myocardium is independently associated with left ventricular dysfunction in patients with prior myocardial infarction.

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    Nakamori, Shiro; Alakbarli, Javid; Bellm, Steven; Motiwala, Shweta R; Addae, Gifty; Manning, Warren J; Nezafat, Reza

    2017-10-01

    To compare remote myocardium native T 1 in patients with chronic myocardial infarction (MI) and controls without MI and to elucidate the relationship of infarct size and native T 1 in the remote myocardium for the prediction of left ventricular (LV) systolic dysfunction after MI. A total of 41 chronic MI (18 anterior MI) patients and 15 age-matched volunteers with normal LV systolic function and no history of MI underwent cardiac magnetic resonance imaging (MRI) at 1.5T. Native T 1 map was performed using a slice interleaved T 1 mapping and late gadolinium enhancement (LGE) imaging. Cine MR was acquired to assess LV function and mass. The remote myocardium native T 1 time was significantly elevated in patients with prior MI, compared to controls, for both anterior MI and nonanterior MI (anterior MI: 1099 ± 30, nonanterior MI: 1097 ± 39, controls: 1068 ± 25 msec, P Remote myocardium native T 1 moderately correlated with LV volume, mass index, and ejection fraction (r = 0.38, 0.50, -0.49, respectively, all P remote myocardium was independently associated with reduced LV ejection fraction, after adjusting for age, gender, infarct size, and comorbidity (β = -0.34, P = 0.03). In chronic MI, the severity of LV systolic dysfunction after MI is independently associated with native T 1 in the remote myocardium. Diffuse myocardial fibrosis in the remote myocardium may play an important pathophysiological role of post-MI LV dysfunction. 1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2017;46:1073-1081. © 2017 International Society for Magnetic Resonance in Medicine.

  18. Lead reduces tension development and the myosin ATPase activity of the rat right ventricular myocardium

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    D.V. Vassallo

    2008-09-01

    Full Text Available Lead (Pb2+ poisoning causes hypertension, but little is known regarding its acute effects on cardiac contractility. To evaluate these effects, force was measured in right ventricular strips that were contracting isometrically in 45 male Wistar rats (250-300 g before and after the addition of increasing concentrations of lead acetate (3, 7, 10, 30, 70, 100, and 300 µM to the bath. Changes in rate of stimulation (0.1-1.5 Hz, relative potentiation after pauses of 15, 30, and 60 s, effect of Ca2+ concentration (0.62, 1.25, and 2.5 mM, and the effect of isoproterenol (20 ng/mL were determined before and after the addition of 100 µM Pb2+. Effects on contractile proteins were evaluated after caffeine treatment using tetanic stimulation (10 Hz and measuring the activity of the myosin ATPase. Pb2+ produced concentration-dependent force reduction, significant at concentrations greater than 30 µM. The force developed in response to increasing rates of stimulation became smaller at 0.5 and 0.8 Hz. Relative potentiation increased after 100 µM Pb2+ treatment. Extracellular Ca2+ increment and isoproterenol administration increased force development but after 100 µM Pb2+ treatment the force was significantly reduced suggesting an effect of the metal on the sarcolemmal Ca2+ influx. Concentration of 100 µM Pb2+ also reduced the peak and plateau force of tetanic contractions and reduced the activity of the myosin ATPase. Results showed that acute Pb2+ administration, although not affecting the sarcoplasmic reticulum activity, produces a concentration-dependent negative inotropic effect and reduces myosin ATPase activity. Results suggest that acute lead administration reduced myocardial contractility by reducing sarcolemmal calcium influx and the myosin ATPase activity. These results also suggest that lead exposure is hazardous and has toxicological consequences affecting cardiac muscle.

  19. Quantification of heart, pericardium, and left ventricular myocardium movements during the cardiac cycle for thoracic tumor radiotherapy

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    Tong Y

    2018-01-01

    Full Text Available Ying Tong,1,2 Yong Yin,1 Jie Lu,1 Tonghai Liu,1 Jinhu Chen,1 Pinjing Cheng,2 Guanzhong Gong1 1Department of Radiation Physics, Shandong Cancer Hospital Affiliated to Shandong University, Jinan, 2School of Nuclear Science and Technology, University of South China, Hengyang, People’s Republic of China Purpose: The purpose of this study was to quantify variations in the heart, pericardium, and left ventricular myocardium (LVM caused by cardiac movement using the breath-hold technique. Patients and methods: In this study, the electrocardiography-gated four-dimensional computed tomography (CT images of 22 patients were analyzed, which were sorted into 20 phases (0–95% according to the cardiac cycle. The heart, pericardium, and LVM were contoured on each phase of the CT images. The positions, volume, dice similarity coefficient (DSC in reference to 0% phase, and morphological parameters (max 3D diameter, roundness, spherical disproportion, sphericity, and surface area in different phases of the heart, pericardium, and LVM were analyzed, which were presented as mean ± standard deviation. Results: The mean values of displacements along the X, Y, and Z axes respectively were as follows: 1.2 mm, 0.6 mm, and 0.6 mm for the heart; 0.5 mm, 0.4 mm, and 0.8 mm for the pericardium; and 1.0 mm, 4.1 mm, and 1.9 mm for the LVM. The maximum variations in volume and DSC respectively were 16.49%±3.85% and 10.08%±2.14% for the heart, 12.62%±3.94% and 5.20%±1.54% for the pericardium, and 24.23%±11.35% and 184.33%±128.61% for the LVM. The differences in the morphological parameters between the maximum and minimum DSC phases for the heart and pericardium were not significantly different (p>0.05 but were significantly different for the LVM (p<0.05. Conclusion: The volumetric and morphological variations of the heart were similar to those of pericardium, and all were significantly smaller than those of the LVM. This inconsistency in the volumetric and

  20. Evaluation of noncoronary sources of left ventricular perfusion to intercoronary collateral-dependent myocardium due to chronic major vessel occlusion: absent contribution of luminal and extracardiac channels

    International Nuclear Information System (INIS)

    Crystal, G.J.; Downey, H.F.; Bashour, F.A.

    1981-01-01

    Liminal contribution to perfusion of collateral-dependent left ventricular (LV) myocardium was evaluated in six dogs. A portion of LV free wall was rendered collateral-dependent by gradual occlusion of left circumflex artery with Ameroid constrictor. Eight to 10 weeks after implantation of constrictor, measurements of LV myocardial flow were made by left atrial injections of 9-10 micro radioactive microspheres. To measure total collateral flow, microspheres were injected under control conditions, and to measure luminal contribution to collateral flow, microspheres were injected after ligation of right coronary artery during extracorporeal perfusion of left common coronary artery (LCCA) with microsphere-free arterial blood, and during stoppage of flow through LCCA. Under control conditions, myocardial blood flow in collateral-dependent region, 1.01 +/- 0.31 ml/min/gm, was not significantly different from that in normal region, 1.06 +/- 0.32 ml/min/gm. Flow from luminal collateral vessels was negligible (less than 0.005 ml/min/gm) in both collateral-dependent and normal myocardium, and was not affected by stoppage of flow through LCCA. These results indicate that luminal collateral vessels, as well as collateral vessels originating from other noncoronary sources, do not contribute significantly to perfusion of normal or collateral-dependent LV myocardium

  1. Characterization of the functional and anatomical differences in the atrial and ventricular myocardium from three species of elasmobranch fishes: smooth dogfish (Mustelus canis), sandbar shark (Carcharhinus plumbeus), and clearnose skate (Raja eglanteria).

    Science.gov (United States)

    Larsen, Julie; Bushnell, Peter; Steffensen, John; Pedersen, Morten; Qvortrup, Klaus; Brill, Richard

    2017-02-01

    We assessed the functional properties in atrial and ventricular myocardium (using isolated cardiac strips) of smooth dogfish (Mustelus canis), clearnose skate (Raja eglanteria), and sandbar shark (Carcharhinus plumbeus) by blocking Ca 2+ release from the sarcoplasmic reticulum (SR) with ryanodine and thapsigargin and measuring the resultant changes in contraction-relaxation parameters and the force-frequency relationship at 20 °C and 30 °C. We also examined ultrastructural differences with electron microscopy. In tissues from smooth dogfish, net force (per cross-sectional area) and measures of the speeds of contraction and relaxation were all higher in atrial than ventricular myocardium at both temperatures. Atrial-ventricular differences were evident in the other two species primarily in measures of the rates of contraction and relaxation. Ryanodine-thapsigargin treatment reduced net force and its maximum positive first derivative (i.e., contractility), and increased time to 50 % relaxation in atrial tissue from smooth dogfish at 30 °C. It also increased times to peak force and half relaxation in clearnose skate atrial and ventricular tissue at both temperatures, but only in atrial tissue from sandbar shark at 30 °C; indicating that SR involvement in excitation-contraction (EC) coupling is species- and temperature-specific in elasmobranch fishes, as it is in teleost fishes. Atrial and ventricular myocardium from all three species displayed a negative force-frequency relationship, but there was no evidence that SR involvement in EC coupling was influenced by heart rate. SR was evident in electron micrographs, generally located in proximity to mitochondria and intercalated discs, and to a lesser extent between the myofibrils; with mitochondria being more numerous in ventricular than atrial myocardium in all three species.

  2. Persistence of neoangiogenesis and cardiomyocyte divisions in right ventricular myocardium of rats born and raised in hypoxic conditions.

    NARCIS (Netherlands)

    Moravec, M.; Turek, Z.I.; Moravec, J.

    2002-01-01

    Effects of chronic hypoxia on capillary and myocyte growth were examined in rats born and raised in a low pressure chamber (equivalent of 3500 m a.s.l.). The animals were sacrificed at the age of 3 months and their hearts were used to study right ventricular growth and vascularization. The results

  3. Análise microscópica do miocárdio ventricular esquerdo em cães soropositivos para cinomose Microscopic analysis of the left ventricular myocardium in positive serum dogs to distemper disease

    Directory of Open Access Journals (Sweden)

    Rodrigo S. de Rezende

    2009-02-01

    Full Text Available Classificado no gênero Morbillivirus da família Paramixoviridae, o vírus da cinomose possui RNA de fita simples de polaridade negativa, é causador de doença multissistêmica, altamente contagiosa e grave dos cães e carnívoros selvagens, e com elevado índice de mortalidade em animais não vacinados ou com falhas vacinais. Com o objetivo de avaliar as alterações histopatológicas no coração, particularmente na região do miocárdio ventricular esquerdo, de cães naturalmente infectados com o vírus da cinomose, foram estudados 35 animais, de ambos os sexos e com idades variadas. Das 35 amostras enviadas ao Laboratório de Medicina Veterinária Preventiva do Hospital Veterinário de Uberaba, 100% (35/35 mostrou-se soropositivas para a cinomose (técnica de imunoensaio em fase sólida e tiveram no miocárdio ventricular esquerdo as seguintes alterações histopatológicas: miocardite, degeneração hialina, hiperemia e hemorragia, com 42,8% (15/35, 31,4% (11/35, 14,3% (5/35 e 11,4% (4/35, respectivamente. Tendo utilizado o teste Qui-Quadrado com nível de significância de 0,05, conclui-se que existe alta correlação (p=0,02 entre os animais infectados com o vírus da cinomose e as alterações histopatológicas observadas no miocárdio ventricular esquerdo.Classified pertaining to the genus Morbillivirus of the Paramyxoviridae family, the canine distemper virus is a RNA single-stranded virus with negative polarity and causes a multisystemic disease, serious and highly contagious for dogs and wild carnivores, with a high mortality rate in non-vaccinated animals or with vaccine fails. With the objective to evaluate heart histopathological alterations, particularly in the left ventricular myocardium, in dogs naturally infected with canine distemper virus, 35 dogs, males and females of different ages, were studied. All the 35 samples sent to the Veterinary Hospital of Uberaba were serum-positive for distemper (immunoassay technique in

  4. No evidence for activated autophagy in left ventricular myocardium at early reperfusion with protection by remote ischemic preconditioning in patients undergoing coronary artery bypass grafting.

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    Nilgün Gedik

    Full Text Available Remote ischemic preconditioning (RIPC by repeated brief limb ischemia/reperfusion reduces myocardial injury in patients undergoing coronary artery bypass grafting (CABG. Activation of signal transducer and activator of transcription 5 (STAT5 in left ventricular (LV myocardium at early reperfusion is associated with such protection. Autophagy, i.e., removal of dysfunctional cellular components through lysosomes, has been proposed as one mechanism of cardioprotection. Therefore, we analyzed whether or not the protection by RIPC is associated with activated autophagy.CABG patients were randomized to undergo RIPC (3×5 min blood pressure cuff inflation/5 min deflation or placebo (cuff deflated before skin incision (n = 10/10. Transmural myocardial biopsies were taken from the LV before cardioplegia (baseline and at early (5-10 min reperfusion. RIPC-induced protection was reflected by decreased serum troponin I concentration area under the curve (194±17 versus 709±129 ng/ml × 72 h, p = 0.002. Western blotting for beclin-1-phosphorylation and protein expression of autophagy-related gene 5-12 (ATG5-12 complex, light chain 3 (LC3, parkin, and p62 was performed. STAT3-, STAT5- and extracellular signal-regulated protein kinase 1/2 (ERK1/2-phosphorylation was used as positive control to confirm signal activation by ischemia/reperfusion.Signals of all analyzed autophagy proteins did not differ between baseline and early reperfusion and not between RIPC and placebo. STAT5-phosphorylation was greater at early reperfusion only with RIPC (2.2-fold, p = 0.02. STAT3- and ERK1/2-phosphorylation were greater at early reperfusion with placebo and RIPC (≥2.7-fold versus baseline, p≤0.05.Protection through RIPC in patients undergoing CABG surgery does not appear to be associated with enhanced autophagy in LV myocardium at early reperfusion.

  5. Effects of a new antiarrhythmic drug SS-68 on electrical activity in working atrial and ventricular myocardium of mouse and their ionic mechanisms

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    Saida K. Bogus

    2015-08-01

    Full Text Available SS-68 is a derivative of indole, which demonstrated strong antiarrhythmic effects not associated with significant QT prolongation in dog models of atrial fibrillation. Therefore, SS-68 was proposed as a new antiarrhythmic drug and the present study is the first describing its effects on action potentials (APs configuration and elucidating the ionic mechanisms of these effects. Sharp microelectrodes were used to record APs in isolated preparations of mouse atrial and ventricular myocardium. In both types of myocardium 10−6 M SS-68 produced reduction of AP duration, 3 × 10−6 M failed to alter AP waveform and 10−5 – 3 × 10−5 M prolonged APs. Sensitivity of main ionic currents to SS-68 was determined using whole-cell patch clamp. Transient potassium current Ito was slightly inhibited by SS-68 with IC50 = 1.43 × 10−4 M. IKur was more sensitive with IC50 = 1.84 × 10−5 M. Background inward rectifier showed very low sensitivity to SS-68 – only 10−4 M SS-68 caused significant reduction of IK1. ICaL was significantly inhibited by 10−6M – 3 × 10−5 M SS-68. The IC50 value for the ICaL was 1.84 × 10−6 M. Thus, main ionic currents of mouse cardiomyocytes are inhibited by SS-68 in the following order of potency: ICaL > IKur > Ito > IK1. While lower concentration of SS-68 shorten APs via suppression of ICaL, higher concentrations inhibit K+-currents leading to APs prolongation.

  6. Islands of spatially discordant APD alternans underlie arrhythmogenesis by promoting electrotonic dyssynchrony in models of fibrotic rat ventricular myocardium

    Science.gov (United States)

    Majumder, Rupamanjari; Engels, Marc C.; de Vries, Antoine A. F.; Panfilov, Alexander V.; Pijnappels, Daniël A.

    2016-04-01

    Fibrosis and altered gap junctional coupling are key features of ventricular remodelling and are associated with abnormal electrical impulse generation and propagation. Such abnormalities predispose to reentrant electrical activity in the heart. In the absence of tissue heterogeneity, high-frequency impulse generation can also induce dynamic electrical instabilities leading to reentrant arrhythmias. However, because of the complexity and stochastic nature of such arrhythmias, the combined effects of tissue heterogeneity and dynamical instabilities in these arrhythmias have not been explored in detail. Here, arrhythmogenesis was studied using in vitro and in silico monolayer models of neonatal rat ventricular tissue with 30% randomly distributed cardiac myofibroblasts and systematically lowered intercellular coupling achieved in vitro through graded knockdown of connexin43 expression. Arrhythmia incidence and complexity increased with decreasing intercellular coupling efficiency. This coincided with the onset of a specialized type of spatially discordant action potential duration alternans characterized by island-like areas of opposite alternans phase, which positively correlated with the degree of connexinx43 knockdown and arrhythmia complexity. At higher myofibroblast densities, more of these islands were formed and reentrant arrhythmias were more easily induced. This is the first study exploring the combinatorial effects of myocardial fibrosis and dynamic electrical instabilities on reentrant arrhythmia initiation and complexity.

  7. Mechanism of the negative force-frequency relationship in physiologically intact rat ventricular myocardium. Studies by intracellular Ca2+ monitor with iodo-1 and by 31P-nuclear magnetic resonance spectroscopy

    International Nuclear Information System (INIS)

    Morii, Isao; Kihara, Yasuki; Sasayama, Shigetake; Konishi, Takashi; Inubushi, Toshiro.

    1996-01-01

    We studied the subcellular mechanisms of the negative force-frequency relationship in rat myocardium by measuring intracellular Ca 2+ transients by indo-1 fluorometry and intracellular pH (pH i ) and phosphate compounds with 31 P-nuclear magnetic resonance (NMR). The data were compared with those from guinea pig hearts, which show a positive force-frequency relationship. By increasing the pacing rate from 3 Hz to 5 Hz, the peak positive first derivative of left ventricular pressure (LVdP/dt) in rat heart decreased by 10±1% (n=6). In contrast to this negative inotropic response, simultaneously measured peak Ca 2+ transients increased by 6±1%. Guinea pig heart (n=6) showed an increase in peak positive LVdP/dt (33±1%) which was associated with an increase in peak Ca 2+ transients (8±1%). Under equivalent experimental conditions in an NMR spectrometer, this increase in the pacing rate did not affect intracellular levels of phosphate compounds in either rat (n=6) or guinea pig heart (n=6). In contrast, pH i showed a decrease of 0.031±0.006 pH units in rat heart, while no changes were observed in guinea pig heart. These results suggest that in physiological rat myocardium, pH i is susceptible to changes in the stimulus frequency and may affect the Ca 2+ -responsiveness of contractile proteins, which results in the negative force-frequency relationship. (author)

  8. Age-dependent changes in expression of alpha1-adrenergic receptors in rat myocardium

    International Nuclear Information System (INIS)

    Schaffer, W.; Williams, R.S.

    1986-01-01

    The expression of alpha 1 -adrenergic receptors within ventricular myocardium of rats ranging in age from 21 days of fetal life to 24 months after birth was measured from [ 125 I] 2-(β hydroxy phenyl) ethylaminomethyl tetralone binding isotherms. No difference was observed in binding affinity between any of the age groups studied. The number of alpha 1 -adrenergic receptors was found to be 60-120% higher in membranes from fetal or immature rats up to 25 days of age when compared with adult animals. The increased expression of alpha 1 -adrenergic receptors in the developing heart relative to that observed in adult heart is consistent with the hypothesis that alpha 1 -adrenergic receptor stimulation may modulate protein synthesis and growth in mammalian myocardium

  9. Identification of viable myocardium in patients with chronic coronary artery disease and left ventricular dysfunction. Comparison of thallium scintigraphy with reinjection and PET imaging with 18F-fluorodeoxyglucose

    International Nuclear Information System (INIS)

    Bonow, R.O.; Dilsizian, V.; Cuocolo, A.; Bacharach, S.L.

    1991-01-01

    In patients with chronic coronary artery disease and left ventricular dysfunction, the distinction between ventricular dysfunction arising from myocardial fibrosis and ischemic, but viable, myocardium has important clinical implications. By positron emission tomography (PET), enhanced fluorine-18-labeled fluorodeoxyglucose (FDG) uptake in myocardial segments with impaired function and reduced blood flow is evidence of myocardial viability. Reinjection of thallium-201 at rest immediately after stress-redistribution imaging may also provide evidence of myocardial viability by demonstrating thallium uptake in regions with apparently irreversible defects. To compare these two methods, we studied 16 patients with chronic coronary artery disease and left ventricular dysfunction, all of whom had irreversible defects on standard exercise-redistribution thallium single-photon emission computed tomography (SPECT) imaging. Thallium was reinjected immediately after the redistribution study, and SPECT images were reacquired. The patients also underwent PET imaging with FDG and oxygen-15-labeled water. A total of 432 myocardial segments were analyzed from comparable transaxial tomograms, of which 166 (38%) had irreversible thallium defects on redistribution images before reinjection. FDG uptake was demonstrated in 121 (73%) of these irreversible defects. Irreversible defects were then subgrouped according to the degree of thallium activity, relative to peak activity in normal regions. Irreversible defects with only mild (60-85% of peak activity) or moderate (50-59% of peak) reduction in thallium activity were considered viable on the basis of FDG uptake in 91% and 84% of these segments, respectively. In contrast, in irreversible defects with severe reduction in thallium activity (less than 50% of peak), FDG uptake was present in 51% of segments

  10. Ultrastructural analysis of the structure and distribution of the adherens junctions in the rats’ ventricular myocardium during postnatal stages of ontogeny after the infl uence of chronic prenatal hypoxia

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    N. S. Petruk

    2013-12-01

    Full Text Available Background. Antenatal and prenatal hypoxia causes changes in all the organs of fetuses and newborns and in the heart, particularly. Hypoxic damage of the cardiovascular system occurs in 40-70% of newborns. Currently we observe the increase of meaning of the morphological studies for the prenatal diagnosis of human’s heart diseases. It’s known that in adaptive remodeling of cardiomyocytes in the postnatal cardiogenesis of rat redistribution of diffusely located intercellular junctions from the periphery to the terminal areas of the cell occurs. The formation of a definitive pattern of intercellular junctions is completed at the puberty. But how chronic prenatal hypoxia influences the specialized adherens junctions in the rats’ ventricular myocardium is completely unknown and this requires further study. Objective. To provide complex qualitative and quantitative comparative ultrastructural analysis of the intercellular connection changes in rat ventricular myocardium on the stages of postnatal ontogenesis in the norm and under the chronic fetal hypoxia. Materials and methods. We have conducted ultrastructural analysis and distribution of the adherens junctions in the rats’ ventricles on the 1st, 3rd, 7th, 14th, 30th days during postnatal ontogeny and among mature animals in the normal development and under the chronic fetal hypoxia. Experimental chronic hypoxia was modeled by intraperitoneal injection of 1% aqueous solution of the NaNO2 in a daily dose of 50 mg/kg of body weight in the term from 10th to 21st days of pregnancy. Transmission electron microscopy, morphometric and statistical methods were applied. Pairwise comparisons between means of different groups were performed using a Student t-test where, for each couple of normally distributed populations, the null hypothesis that the means are equal was verified. Results. Pronounced increase (80,6%; p <0,05 of the content of desmosomes in the intercalated disk in the period from 7th

  11. The inotropic effect of the active metabolite of levosimendan, OR-1896, is mediated through inhibition of PDE3 in rat ventricular myocardium.

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    Øivind Ørstavik

    Full Text Available We recently published that the positive inotropic response (PIR to levosimendan can be fully accounted for by phosphodiesterase (PDE inhibition in both failing human heart and normal rat heart. To determine if the PIR of the active metabolite OR-1896, an important mediator of the long-term clinical effects of levosimendan, also results from PDE3 inhibition, we compared the effects of OR-1896, a representative Ca2+ sensitizer EMD57033 (EMD, levosimendan and other PDE inhibitors.Contractile force was measured in rat ventricular strips. PDE assay was conducted on rat ventricular homogenate. cAMP was measured using RII_epac FRET-based sensors.OR-1896 evoked a maximum PIR of 33 ± 10% above basal at 1 μM. This response was amplified in the presence of the PDE4 inhibitor rolipram (89 ± 14% and absent in the presence of the PDE3 inhibitors cilostamide (0.5 ± 5.3% or milrinone (3.2 ± 4.4%. The PIR was accompanied by a lusitropic response, and both were reversed by muscarinic receptor stimulation with carbachol and absent in the presence of β-AR blockade with timolol. OR-1896 inhibited PDE activity and increased cAMP levels at concentrations giving PIRs. OR-1896 did not sensitize the concentration-response relationship to extracellular Ca2+. Levosimendan, OR-1896 and EMD all increased the sensitivity to β-AR stimulation. The combination of either EMD and levosimendan or EMD and OR-1896 further sensitized the response, indicating at least two different mechanisms responsible for the sensitization. Only EMD sensitized the α1-AR response.The observed PIR to OR-1896 in rat ventricular strips is mediated through PDE3 inhibition, enhancing cAMP-mediated effects. These results further reinforce our previous finding that Ca2+ sensitization does not play a significant role in the inotropic (and lusitropic effect of levosimendan, nor of its main metabolite OR-1896.

  12. Repair of the myocardium infarct, with intracoronary implant of mother cells (stem cells) precocious improvement of the ventricular function and the ischemy (first reports of the TECELCOR report)

    International Nuclear Information System (INIS)

    Fernandez Vina, Roberto; Vrsalovic, Francisco; Andrin, Oberdan and others

    2004-01-01

    Twenty patients who suffered extensive anterior myocardial infarction with an evolution of 5 to 72 hours were submitted to a primary PTCA with Stent. The ventricular ejection fraction oscillated between 21 to 30% in correlation to the bidimensional echocardiography. Between the 7th and 12th day, mononuclear CD 34(+) and CD 38(-) cells extracted from the patient's bone marrow were implanted through the anterior descendent coronary artery, with occlusion of the anterior coronary vein, in an average amount of 22 x 10 P6. echocardiographic controls were performed each 7 days until 60 days, noticing a progressive increment in the ejection fraction (EF) from 25 to 45% in the first 60 days, and an improvement of the EF up to 80% after 90 days. Between 90 and 120 days after, a coronary ventriculography was performed, and the permeability of all the implanted stents and an improvement of the EF up to 80% with respect to the basal EF, were observed. The Spect studies were negative with negative ergonometry at 700 kgm. This group of patients was comparing red with 16 patients who were submitted only to primary PTCA with Stent. They had an increase of only 45% of the EF respect to the basal one in the next 90 days and 12 % presented restenosis. Stems cells implant improves the left ventricular performance after a myocardial infarction and it seems to avoid the coronary post-restenosis

  13. Reversible left ventricular dysfunction - important clinical problem of contemporary cardiology

    International Nuclear Information System (INIS)

    Witkowski, A.

    1994-01-01

    An important clinical issue there is determination whether left ventricular damages are reversible or not single photon emission computed tomography and positron computed tomography techniques are shown to provide valuable data in this problem. Article describes basic syndromes connected with left ventricular dysfunction, namely: hibernating myocardium, stunned myocardium and ischemic myocardium preconditioning. (author). 18 refs

  14. Automated three-dimensional tracking of the left ventricular myocardium in time-resolved and dose-modulated cardiac CT images using deformable image registration.

    Science.gov (United States)

    Gupta, Vikas; Lantz, Jonas; Henriksson, Lilian; Engvall, Jan; Karlsson, Matts; Persson, Anders; Ebbers, Tino

    Assessment of myocardial deformation from time-resolved cardiac computed tomography (4D CT) would augment the already available functional information from such an examination without incurring any additional costs. A deformable image registration (DIR) based approach is proposed to allow fast and automatic myocardial tracking in clinical 4D CT images. Left ventricular myocardial tissue displacement through a cardiac cycle was tracked using a B-spline transformation based DIR. Gradient of such displacements allowed Lagrangian strain estimation with respect to end-diastole in clinical 4D CT data from ten subjects with suspected coronary artery disease. Dice similarity coefficient (DSC), point-to-curve error (PTC), and tracking error were used to assess the tracking accuracy. Wilcoxon signed rank test provided significance of tracking errors. Topology preservation was verified using Jacobian of the deformation. Reliability of estimated strains and torsion (normalized twist angle) was tested in subjects with normal function by comparing them with normal strain in the literature. Comparison with manual tracking showed high accuracy (DSC: 0.99±0.05; PTC: 0.56mm±0.47 mm) and resulted in determinant(Jacobian)>0 for all subjects, indicating preservation of topology. Average radial (0.13 mm), angular (0.64) and longitudinal (0.10 mm) tracking errors for the entire cohort were not significant (p > 0.9). For patients with normal function, average strain [circumferential, radial, longitudinal] and peak torsion estimates were: [-23.5%, 31.1%, -17.2%] and 7.22°, respectively. These estimates were in conformity with the reported normal ranges in the existing literature. Accurate wall deformation tracking and subsequent strain estimation are feasible with the proposed method using only routine time-resolved 3D cardiac CT. Copyright © 2018 Society of Cardiovascular Computed Tomography. Published by Elsevier Inc. All rights reserved.

  15. A Review of Neurogenic Stunned Myocardium

    OpenAIRE

    Biso, Sylvia; Wongrakpanich, Supakanya; Agrawal, Akanksha; Yadlapati, Sujani; Kishlyansky, Marina; Figueredo, Vincent

    2017-01-01

    Neurologic stunned myocardium (NSM) is a phenomenon where neurologic events give rise to cardiac abnormalities. Neurologic events like stroke and seizures cause sympathetic storm and autonomic dysregulation that result in myocardial injury. The clinical presentation can involve troponin elevation, left ventricular dysfunction, and ECG changes. These findings are similar to Takotsubo cardiomyopathy and acute coronary syndrome. It is difficult to distinguish NSM from acute coronary syndrome bas...

  16. Four cases of right ventricular dysplasia

    International Nuclear Information System (INIS)

    Takamura, Ichiro; Ando, Joji; Miyamoto, Atsushi; Kobayashi, Takeshi; Sakamoto, Sanya; Yasuda, Hisakazu

    1985-01-01

    Finding of 81 Kr right ventriculography and 201 Tl myocardial perfusion imaging in 4 patients with right ventricular dysplasia (RVD) were compared with those in 28 patients with dilated cardiomyopathy. Remarkably dilated right ventricle was detected on 201 Tl myocardial perfusion imaging in the RVD group. In a patient with RVD who died suddenly, perfusion defect of the left ventricular myocardium, a decreased right ventricular ejection fraction, and an increased right ventricular end diastolic volume were seen. Perfusion defect of the left ventricular myocardium was seen in 10 of the 28 patients with dilated cardiomyopathy, 4 of whom died suddenly. In these 4 patients, a decreased left ventricular ejection fraction and an increased right ventricular end diastolic volume were seen. These findings obtained by the radionuclide techniques suggested that there are differences in cardiac dysfunction of the both ventricles between the groups with RVD and dilated cardiomyopathy. (Namekawa, K.)

  17. Diagnosis of Non-compacted Myocardium of the Left Ventricle in Children

    Directory of Open Access Journals (Sweden)

    I.B. Yershova

    2014-05-01

    Full Text Available The authors presented a review of published literature data on rare congenital abnormalities in children — a non-compacted myocardium of the left ventricle, which refers to unclassified cardiomyopathy. This pathology by the American Heart Association classification relates to genetic cardiomyopathy. Non-compacted myocardium of the left ventricle in children develops due to violation of myocardial induration of the fetus in utero. Diagnosis of the disease is difficult due to the lack of specific clinical signs. The authors also presented a clinical case of non-compacted left ventricular myocardium in 6-year-old girl.

  18. A Review of Neurogenic Stunned Myocardium

    Science.gov (United States)

    Wongrakpanich, Supakanya; Agrawal, Akanksha; Yadlapati, Sujani; Kishlyansky, Marina; Figueredo, Vincent

    2017-01-01

    Neurologic stunned myocardium (NSM) is a phenomenon where neurologic events give rise to cardiac abnormalities. Neurologic events like stroke and seizures cause sympathetic storm and autonomic dysregulation that result in myocardial injury. The clinical presentation can involve troponin elevation, left ventricular dysfunction, and ECG changes. These findings are similar to Takotsubo cardiomyopathy and acute coronary syndrome. It is difficult to distinguish NSM from acute coronary syndrome based on clinical presentation alone. Because of this difficulty, a patient with NSM who is at high risk for coronary heart disease may undergo cardiac catheterization to rule out coronary artery disease. The objective of this review of literature is to enhance physician's awareness of NSM and its features to help tailor management according to the patient's clinical profile. PMID:28875040

  19. Neurogenic stunned myocardium following hemorrhagic cerebral contusion

    International Nuclear Information System (INIS)

    Deleu, D.; Miyares, F.; Kettern, M.; Kumar, S.; Hassens, Y.; Salim, K.

    2007-01-01

    Neurogenic stunned myocardium NSM is a well-known complication of subarachnoidal hemorrhage, but has been reported rarely in association with other central nervous system disorders. A case of NSM is described in a patient with hemorrhagic brain contusion associated with cerebral edema. An 18-year-old man was admitted with severe cranial trauma following a car roll-over. Six days after admission, he developed findings suggestive for NSM. The troponin T and creatine kinase-MB level were elevated and echocardiogram showed apical and inferoposterior hypokinesis and diffuse left ventricular akinesis with severely reduced ejection fraction 18%. Invasive measurements confirmed low cardiac output. His cardiac function resolved completely within 6 days after decompressive craniotomy. This case supports the presumed unifying role of the increased intracranial pressure, probably triggering a vigorous sympathetic outflow hyperactivity leading to NSM. (author)

  20. Abnormal mitochondrial respiration in failed human myocardium.

    Science.gov (United States)

    Sharov, V G; Todor, A V; Silverman, N; Goldstein, S; Sabbah, H N

    2000-12-01

    Chronic heart failure (HF) is associated with morphologic abnormalities of cardiac mitochondria including hyperplasia, reduced organelle size and compromised structural integrity. In this study, we examined whether functional abnormalities of mitochondrial respiration are also present in myocardium of patients with advanced HF. Mitochondrial respiration was examined using a Clark electrode in an oxygraph cell containing saponin-skinned muscle bundles obtained from myocardium of failed explanted human hearts due to ischemic (ICM, n=9) or idiopathic dilated (IDC, n=9) cardiomyopathy. Myocardial specimens from five normal donor hearts served as controls (CON). Basal respiratory rate, respiratory rate after addition of the substrates glutamate and malate (V(SUB)), state 3 respiration (after addition of ADP, V(ADP)) and respiration after the addition of atractyloside (V(AT)) were measured in scar-free muscle bundles obtained from the subendocardial (ENDO) and subepicardial (EPI) thirds of the left ventricular (LV) free wall, interventricular septum and right ventricular (RV) free wall. There were no differences in basal and substrate-supported respiration between CON and HF regardless of etiology. V(ADP)was significantly depressed both in ICM and IDC compared to CON in all the regions studied. The respiratory control ratio, V(ADP)/V(AT), was also significantly decreased in HF compared to CON. In both ICM and IDC, V(ADP)was significantly lower in ENDO compared to EPI. The results indicate that mitochondrial respiration is abnormal in the failing human heart. The findings support the concept of low myocardial energy production in HF via oxidative phosphorylation, an abnormality with a potentially impact on global cardiac performance. Copyright 2000 Academic Press.

  1. Hypertrophic cardiomyopathy with mid-ventricular obstruction and apical aneurysm

    Directory of Open Access Journals (Sweden)

    N.D. Oryshchyn

    2016-11-01

    Full Text Available A case report of apical left ventricular aneurysm in patient with hypertrophic cardiomyopathy with mid-ventricular obstruction (diagnosis and surgical treatment is presented. We revealed apical aneurysm and mid-ventricular obstruction during echocardiography and specified anatomical characteristics of aneurysm during computer tomography. There was no evidence of obstructive coronary artery disease during coronary angiography. Taking into consideration multiple cerebral infarcts, aneurysm resection and left ventricular plastics was performed. Electronic microscopy of myocardium confirmed the diagnosis of hypertrophic cardiomyopathy.

  2. Stretch-dependent slow force response in isolated rabbit myocardium is Na+ dependent.

    Science.gov (United States)

    von Lewinski, Dirk; Stumme, Burkhard; Maier, Lars S; Luers, Claus; Bers, Donald M; Pieske, Burkert

    2003-03-15

    Stretch induces functional and trophic effects in mammalian myocardium via various signal transduction pathways. We tested stretch signal transduction on immediate and slow force response (SFR) in rabbit myocardium. Experiments were performed in isolated right ventricular muscles from adult rabbit hearts (37 degrees C, 1 Hz stimulation rate, bicarbonate-buffer). Muscles were rapidly stretched from 88% of optimal length (L88) to near optimal length (L98) for functional analysis. The resulting immediate and slow increases in twitch force (first phase and SFR, respectively) were assessed at reduced [Na+]o or without and with blockade of stretch activated ion channels (SACs), angiotensin-II (AT1) receptors, endothelin-A (ET(A)) receptors, Na+/H+-exchange (NHE1), reverse mode Na+/Ca2+-exchange (NCX), or Na+/K+-ATPase. The effects of stretch on sarcoplasmic reticulum Ca2+-load were characterized using rapid cooling contractures (RCCs). Intracellular pH was measured in BCECF-AM loaded muscles, and action potential duration (APD) was assessed using floating electrodes. On average, force increased to 216+/-8% of the pre-stretch value during the immediate phase, followed by a further increase to 273+/-10% during the SFR (n=81). RCCs significantly increased during SFR, whereas pH and APD did not change. Neither inhibition of SACs, AT1, or ET(A) receptors affected the stretch-dependent immediate phase nor SFR. In contrast, SFR was reduced by NHE inhibition and almost completely abolished by reduced [Na+]o or inhibition of reverse-mode NCX, whereas increased SFR was seen after raising [Na+]i by Na+/K+-ATPase inhibition. The data demonstrate the existence of a delayed, Na+- and Ca2+-dependent but pH and APD independent SFR to stretch in rabbit myocardium. This inotropic response appears to be independent of autocrine/paracrine AT1 or ET(A) receptor activation, but mediated through stretch-induced activation of NHE and reverse mode NCX.

  3. Characterization of the positive and negative inotropic effects of acetylcholine in the human myocardium

    NARCIS (Netherlands)

    X.Y. Du (Xiaoyi); R.G. Schoemaker (Regien); E. Bos (Egbert); P.R. Saxena (Pramod Ranjan)

    1995-01-01

    textabstractIn the human isolated myocardium, acetylcholine (10−9 to 10−3 M) elicited a biphasic inotropic effect (a decrease in the lower and an increase in the higher concentration range) in atrial and a positive inotropic effect in ventricular trabeculae. However, under conditions of raised

  4. Arrhythmogenic right ventricular dysplasia: MRI findings

    International Nuclear Information System (INIS)

    Wall, E.E. van der; Bootsma, M.M.; Schalij, M.J.; Kayser, H.W.M.; Roos, A. de

    2000-01-01

    Arrhythmogenic right ventricular dysplasia (ARVD) is a heart muscle disorder of unknown cause that is characterized pathologically by fibrofatty replacement of the right ventricular myocardium. Clinical manifestations include structural and functional malformations of the right ventricle, electrocardiographic abnormalities, and presentation with ventricular tachycardias with left bundle branch pattern or sudden death. The disease is often familial with an autosomal inheritance. In addition to right ventricular dilatation, right ventricular aneurysms are typical deformities of ARVD and they are distributed in the so-called ''triangle of dysplasia'', i. e., right ventricular outflow tract, apex, and infundibulum. Ventricular aneurysms at these sites can be considered pathognomonic of ARVD. Another typical hallmark of ARVD is fibrofatty infiltration of the right ventricular free wall. These functional and morphologic characteristics are relevant to clinical imaging investigations such as contrast angiography, echocardiography, radionuclide angiography, ultrafast computed tomography, and magnetic resonance imaging (MRI). Among these techniques, MRI allows the clearest visualization of the heart, in particular because the right ventricle is involved, which is usually more difficult to explore with the other imaging modalities. Furthermore, MRI offers the specific advantage of visualizing adipose infiltration as a bright signal of the right ventricular myocardium. MRI provides the most important anatomic, functional, and morphologic criteria for diagnosis of ARVD within one single study. As a result, MRI appears to be the optimal imaging technique for detecting and following patients with clinical suspicion of ARVD. (orig.) [de

  5. Myocardium tracking via matching distributions.

    Science.gov (United States)

    Ben Ayed, Ismail; Li, Shuo; Ross, Ian; Islam, Ali

    2009-01-01

    The goal of this study is to investigate automatic myocardium tracking in cardiac Magnetic Resonance (MR) sequences using global distribution matching via level-set curve evolution. Rather than relying on the pixelwise information as in existing approaches, distribution matching compares intensity distributions, and consequently, is well-suited to the myocardium tracking problem. Starting from a manual segmentation of the first frame, two curves are evolved in order to recover the endocardium (inner myocardium boundary) and the epicardium (outer myocardium boundary) in all the frames. For each curve, the evolution equation is sought following the maximization of a functional containing two terms: (1) a distribution matching term measuring the similarity between the non-parametric intensity distributions sampled from inside and outside the curve to the model distributions of the corresponding regions estimated from the previous frame; (2) a gradient term for smoothing the curve and biasing it toward high gradient of intensity. The Bhattacharyya coefficient is used as a similarity measure between distributions. The functional maximization is obtained by the Euler-Lagrange ascent equation of curve evolution, and efficiently implemented via level-set. The performance of the proposed distribution matching was quantitatively evaluated by comparisons with independent manual segmentations approved by an experienced cardiologist. The method was applied to ten 2D mid-cavity MR sequences corresponding to ten different subjects. Although neither shape prior knowledge nor curve coupling were used, quantitative evaluation demonstrated that the results were consistent with manual segmentations. The proposed method compares well with existing methods. The algorithm also yields a satisfying reproducibility. Distribution matching leads to a myocardium tracking which is more flexible and applicable than existing methods because the algorithm uses only the current data, i.e., does not

  6. Pathomorphological Changes of the Myocardium in Canine Dilated Cardiomyopathy (DCM

    Directory of Open Access Journals (Sweden)

    Janus Izabela

    2015-04-01

    Full Text Available The study was conducted on ventricular and atrial wall preparations from 11 dogs with clinically diagnosed dilated cardiomyopathy. After fixation, the specimens were stained with haematoxylin and eosin and Masson-Goldner trichrome technique. Parenchymal changes (fibrosis and fatty infiltration, vascular changes (congestion and coronary vessel wall hypertrophy, degenerative changes (loss of striation, changes in cardiomycyte and nuclei structure, and presence of inflammatory infiltrates (mononuclear and polynuclear were estimated. Complex histological changes in both ventricular and atrial muscles were shown. It was not determined whether the processes occurring in the myocardium have a primary character, or are a consequence of developing heart failure. Such issues will be put under further and more detailed examination.

  7. Neurogenic Stunned Myocardium Associated with Acute Spinal Cord Infarction: A Case Report

    Directory of Open Access Journals (Sweden)

    Gillian A. Beauchamp

    2012-01-01

    Full Text Available Introduction. Neurogenic stunned myocardium (NSM is a reversible cardiomyopathy resulting in transient left ventricular apical ballooning presumed to result from catecholamine surge occurring under physiologic stress. Acute spinal cord ischemia is a rare ischemic vascular lesion. We report a case of neurogenic stunned myocardium occurring in the setting of acute spinal cord infarction. Methods. Singe case report was used. Results. We present the case of a 63-year-old female with a history of prior lacunar stroke, hypertension, chronic back pain, and hypothyroidism who presented with a brief episode of diffuse abdominal and bilateral lower extremity pain which progressed within minutes to bilateral lower extremity flaccid paralysis. MRI of the spinal cord revealed central signal hyperintensity of T2-weighted imaging from conus to T8 region, concerning for acute spinal cord ischemia. Transthoracic echocardiogram was performed to determine if a cardiac embolic phenomenon may have precipitated this ischemic event and showed left ventricular apical hypokinesis and ballooning concerning for NSM. Conclusion. Neurogenic stunned myocardium is a reversible cardiomyopathy which has been described in patients with physiologic stress resulting in ventricular apical ballooning. Our case suggests that it is possible for neurogenic stunned myocardium to occur in the setting of acute spinal cord ischemia.

  8. Systolic ventricular filling.

    Science.gov (United States)

    Torrent-Guasp, Francisco; Kocica, Mladen J; Corno, Antonio; Komeda, Masashi; Cox, James; Flotats, A; Ballester-Rodes, Manel; Carreras-Costa, Francesc

    2004-03-01

    The evidence of the ventricular myocardial band (VMB) has revealed unavoidable coherence and mutual coupling of form and function in the ventricular myocardium, making it possible to understand the principles governing electrical, mechanical and energetical events within the human heart. From the earliest Erasistratus' observations, principal mechanisms responsible for the ventricular filling have still remained obscured. Contemporary experimental and clinical investigations unequivocally support the attitude that only powerful suction force, developed by the normal ventricles, would be able to produce an efficient filling of the ventricular cavities. The true origin and the precise time frame for generating such force are still controversial. Elastic recoil and muscular contraction were the most commonly mentioned, but yet, still not clearly explained mechanisms involved in the ventricular suction. Classical concepts about timing of successive mechanical events during the cardiac cycle, also do not offer understandable insight into the mechanism of the ventricular filling. The net result is the current state of insufficient knowledge of systolic and particularly diastolic function of normal and diseased heart. Here we summarize experimental evidence and theoretical backgrounds, which could be useful in understanding the phenomenon of the ventricular filling. Anatomy of the VMB, and recent proofs for its segmental electrical and mechanical activation, undoubtedly indicates that ventricular filling is the consequence of an active muscular contraction. Contraction of the ascendent segment of the VMB, with simultaneous shortening and rectifying of its fibers, produces the paradoxical increase of the ventricular volume and lengthening of its long axis. Specific spatial arrangement of the ascendent segment fibers, their interaction with adjacent descendent segment fibers, elastic elements and intra-cavitary blood volume (hemoskeleton), explain the physical principles

  9. Left Ventricular Electromechanical Mapping: A Case Study of Functional Assessment in Coronary Intervention

    OpenAIRE

    Perin, Emerson C.; Silva, Guilherme V.; Sarmento-Leite, Rogerio

    2000-01-01

    Electromechanical mapping is a new diagnostic tool that can be used to identify viable myocardium. In the case reported here, the technique was used before intervention to map areas of viable myocardium; post-intervention mapping showed improved mechanical function of the revascularized areas. Electromechanical mapping offers the potential of assessing left ventricular function in the cardiac catheterization laboratory before and after interventional procedures.

  10. Ventricular and myocardial scintiscanning: Methodical fundamentals

    International Nuclear Information System (INIS)

    Standke, R.; Hoer, G.; Maul, F.D.

    1984-01-01

    Nuclear cardiology is concerned with non invasive procedures to quantitate global and regional left ventricular function (Radionuclide ventriculography), also the imaging of vitally perfused myocardium (Myocardial scintigraphy) is achieved. A gammacamera and a minicomputer are necessary. Radionuclide ventriculography enables the analysis of global and regional time dependent left ventricular volume curves and hence the evaluation of contraction and contractility of the heart muscle. The basis is a sequence of scans covering an average heartcycle. This sequence may be produced either by first pass or equilibrium technique. Myocardial scintigraphy at rest images vital myocardium, scans immediately after exercise represent the interference of myocardial perfusion and muscle mass. The regional difference (Redistribution) between normalized exercise- and rest scans provide quantitative parameters to detect impairment of exercise-induced myocardial perfusion anomalies. The procedures of sectorial analysis of left ventricular function and myocardial perfusion are presented. (orig.) [de

  11. Role of ventricular tachycardia ablation in arrhythmogenic right ventricular cardiomyopathy

    Directory of Open Access Journals (Sweden)

    Alberto Cipriani

    2017-11-01

    Full Text Available Arrhythmogenic right ventricular cardiomyopathy (ARVC is characterized by progressive fibro-fatty replacement of the myocardium that represents the substrate for recurrent sustained ventricular tachycardia (VT. These arrhythmias characterize the clinical course of a sizeable proportion of patients and have significant implications for their quality of life and long-term prognosis. Antiarrhythmic drugs are often poorly tolerated and usually provide incomplete control of arrhythmia relapses. Catheter ablation is a potentially effective strategy to treat frequent VT episodes and ICD shocks in ARVC patients. The aims of this review are to discuss the electrophysiological and electroanatomic substrates of ventricular tachycardia in patients with ARVC and to analyze the role of catheter ablation in their management with particular reference to selection of patients, technical issues, potential complications and outcomes.

  12. Effects of isoproterenol on myocardium

    International Nuclear Information System (INIS)

    Barker, M.E.; Lieber, J.G.; Budinger, T.F.

    1982-01-01

    In the course of autoradiographic studies designed to localize 14 C-taurine within the cells of the rat myocardium, severe tissue damage was noted after stimulation by very low levels of isoproterenol. This β-adrenergic agonist had previously been shown by others to modulate taurine uptake by what appeared to be a very specific mechanism, but our studies have led to a different mechanism. Within four hours after injection of isoproterenol at all concentrations used, pronounced edema of myocytes in the subendocardium was noted; this was followed by an inflammatory reation and degeneration of mitochondria and myofilaments

  13. Arrhythmogenic right ventricular cardiomyopathy in a dog : case report

    Directory of Open Access Journals (Sweden)

    A.J. Möhr

    2000-07-01

    Full Text Available An 8-month-old Labrador retriever bitch was evaluated for sudden-onset, progressive abdominal distension. Physical examination revealed an exaggerated inspiratory effort, severe ascites, bilateral jugular vein distension, and hypokinetic femoral arterial pulses. Thoracic auscultation detected tachycardia with muffled heart sounds, without audible cardiac murmurs. Thoracic radiographs identified severe right ventricular enlargement and pleural effusion. The electrocardiogram was consistent with incomplete right bundle branch block or right ventricular enlargement. Echocardiography demonstrated severe right ventricular and atrial dilation, secondary tricuspid regurgitation, and thinning and hypocontractility of the right ventricular myocardium. Left heart chamber sizes were slightly decreased, with normal left ventricular contractility. Adiagnosis of arrhythmogenic right ventricular cardiomyopathy was reached, based on the characteristic clinical, electrocardiographic, radiographic and echocardiographic findings, and the exclusion of other causes of isolated right ventricular failure. Treatment effected good control of clinical signs, until acutely decompensated congestive right heart failure led to euthanasia after 4 months. Arrhythmogenic right ventricular cardiomyopathy is a well-described clinical entity in humans, and has previously been documented in 3 male dogs. The condition is characterised by progressive fibro-adipose replacement of right ventricular myocardium, while the left ventricle usually remains unaffected. It should be considered a differential diagnosis in any young dog presented with isolated right heart failure, syncope, or unexplained ventricular tachyarrhythmias. This article reports the 1st case of arrhythmogenic right ventricular cardiomyopathy in a female dog, and highlights its echocardiographic features.

  14. Metabolic reserve in normal myocardium assessed by positron emission tomography with C-11 palmitate

    International Nuclear Information System (INIS)

    Tamaki, Nagara; Kawamoto, Masahide; Takahashi, Norio; Yonekura, Yoshiharu; Magata, Yasuhiro; Nohara, Ryuji; Kambara, Hirofumi; Kawai, Chuichi; Konishi, Junji

    1991-01-01

    Positron emission tomography (PET) with C-11 palmitate has been used in estimating the myocardial utilization of free fatty acid. To assess the metabolic reserve in normal subjects, a PET study was performed at control and during dobutamine infusion at 2 hour intervals in 5 normal subjects. Following monoexponential curve fitting of the time activity curve of the myocardium, the clearance half time (min) and residual fraction (%) were calculated as indices of β-oxydation of free fatty acid. A significant increase in the heart rate and systolic blood pressure were observed during dobutamine infusion (65±5 vs 100±29 bpm, p<0.05 and 119±12 vs 144±16 mmHg, p<0.01, respectively). The clearance half-time and the residual fraction were significantly decreased (23.4±2.6 vs 15.8±2.3 min and 67.0±2.5 vs 58.6±4.0%, p<0.05, each). When the left ventricular myocardium was divided into 4 segments, these indices were similar at control and uniformly decreased without regional differences during dobutamine infusion. These data suggest that β-oxydation of free fatty acid may be uniformly increased in the left ventricular myocardium in relation to the increase in cardiac work in normal subjects. PET with C-11 palmitate at control and during dobutamine infusion is considered to be promising in assessing metabolic reserve in the myocardium. (author)

  15. Anisotropy of the apparent frequency dependence of backscatter in formalin fixed human myocardium.

    Science.gov (United States)

    Hall, C S; Verdonk, E D; Wickline, S A; Perez, J E; Miller, J G

    1997-01-01

    Measurements of the frequency dependence of ultrasonic backscatter are presented for specific angles of insonification for regions of infarcted and noninfarcted human myocardium. A 5-MHz transducer was used to insonify cylindrical cores taken from 7 noninfarcted regions and 12 infarcted regions of the left ventricular free wall of 6 formalin-fixed human hearts explanted because of ischemic cardiomyopathy. The dependence of apparent (uncompensated for diffraction effects and attenuation) backscatter on frequency was approximated by a power-law dependence, magnitude of B(f)2 = afn. Under ideal conditions in a lossless medium, the effect of not compensating for the effects of diffraction and attenuation leads to the value of n to be 2.0 for Rayleigh scatterers while the frequency dependence of the fully compensated backscatter coefficient would be f4. The value of n was determined over the frequency range, 3-7 MHz. Both nonifarcted and infarcted myocardium exhibited anisotropy of the frequency dependence of backscatter, with maxima occurring at angles that were perpendicular to the predominant myofiber direction and minima when parallel to the fibers. Perpendicular insonification yielded results for n of 1.8 +/- 0.1 for noninfarcted myocardium and 1.2 +/- 0.1 for infarcted myocardium while parallel insonification yielded results of 0.4 +/- 0.1 for noninfarcted and 0.0 +/- 0.1 for infarcted myocardium. The functional form of the angle-dependent backscatter is similar for both noninfarcted and infarcted myocardium, although the frequency dependence is clearly different for both tissue states for all angles of insonification. The results of this study indicate that the anisotropy of the frequency dependence of backscatter may play a significant role in ultrasonic imaging and is an important consideration for ultrasonic tissue characterization in myocardium.

  16. Radionuclide imaging in primary and secondary disorders of the myocardium

    International Nuclear Information System (INIS)

    Follansbee, W.P.

    1987-01-01

    The list of all potential causes of myocardial disease or injury is an extensive one: a condensed version is presented. Conceptually these processes can be categorized into those which are, or appear to be, primary to the myocardium and those which secondarily involve it. Nuclear imaging procedures, particularly those used to assess ventricular function, are in a general sense potentially applicable to the clinical evaluation of any of these entities. In certain of these conditions, however, nuclear cardiac procedures have a demonstrated or potential additional and more specific role for the diagnosis and quantification of the entity. A number of these, including coronary artery disease, valvular heart disease, cor pulmonale, and myocardial trauma, are the topics of other chapters and, therefore, are not dealt with further here. The remainder of the myocardial disorders in which nuclear imaging procedures have a recognized or potential specific role are the focus of this discussion

  17. A case report of arrhythmogenic right ventricular dysplasia

    Directory of Open Access Journals (Sweden)

    Henry Anselmo Mayala

    2013-07-01

    Full Text Available Background Arrhythmogenic right ventricular dysplasia is an autosomal dominant disorder affecting parts of myocardium known as desmosomes, areas on the surface of heart muscle cells which link the cells together. The hallmark feature is fibro-fatty replacement of the right ventricle myocardium characterized by hypokinetic areas with associated arrhythmias originating in the right ventricle. Case Presentation In this report a 42 year old man was admitted at Wuhan union Hospital with the presenting complaints of visual hallucination and difficulty in breathing on exertion, with a family history of sudden death. Clinical and imaging findings are suggestive of Arrhythmogenic right ventricular dysplasia. Conclusion Despite being among the rare cardiac disease, Arrhythmogenic right ventricular dysplasia is an important cause of ventricular arrhythmias in children and young adults, it is also responsible for sudden cardiac death in the young population, making it necessary for this case report.

  18. A case report of arrhythmogenic right ventricular dysplasia

    Directory of Open Access Journals (Sweden)

    Henry Anselmo Mayala

    2013-01-01

    Full Text Available Background Arrhythmogenic right ventricular dysplasia is an autosomal dominant disorder affecting parts of myocardium known as desmosomes, areas on the surface of heart muscle cells which link the cells together. The hallmark feature is fibro-fatty replacement of the right ventricle myocardium characterized by hypokinetic areas with associated arrhythmias originating in the right ventricle. CasePresentation Inthisreporta42yearoldmanwasadmittedatWuhanunion Hospital with the presenting complaints of visual hallucination and difficulty in breathing on exertion, with a family history of sudden death. Clinical and imaging findings are suggestive of Arrhythmogenic right ventricular dysplasia. Conclusion Despitebeingamongtherarecardiacdisease,Arrhythmogenicright ventricular dysplasia is an important cause of ventricular arrhythmias in children and young adults, it is also responsible for sudden cardiac death in the young population, making it necessary for this case report.

  19. Delayed uptake and washout of contrast in non-viable infarcted myocardium shown with dynamic computed tomography

    DEFF Research Database (Denmark)

    Udholm, Sebastian; Laugesen, Sofie; Agger, Peter

    2014-01-01

    BACKGROUND: Assessment of ischemic but potentially viable myocardium plays an important role in the planning of coronary revascularization. Until now SPECT, PET, and MRI have been used to identify viable myocardium. Computed tomography (CT) is increasingly used to diagnose coronary atherosclerosis...... descending artery, followed by removal of the balloon and reperfusion. Four pigs died due to refractory ventricular fibrillation. After 6 weeks, dynamic cardiac CT was performed assessing both wall motion and contrast attenuation. Measurements of attenuation values in Hounsfield units (HU) in the infarct...

  20. Arrhythmogenic right ventricular dysplasia: A case report

    Directory of Open Access Journals (Sweden)

    Tessa Negrín Valdés

    2015-10-01

    Full Text Available Arrhythmogenic right ventricular dysplasia is a heart muscle disease that predominantly affects the right ventricle, bringing about the replacement of normal myocardium with fatty or fibrofatty tissue and causing sudden death in young individuals. Ventricular tachycardia is an important clinical manifestation, although there are reports of right or global heart failure. The diagnosis is confirmed by echocardiography and magnetic resonance imaging. The case of a 65-year-old former smoker, with hypertension and ischemic heart disease, a history of effort syncope symptoms and proven non-sustained ventricular tachycardia, with morphology of left bundle branch block, is reported. Relevant diagnostic studies were performed, and echocardiographic elements which were compatible with arrhythmogenic right ventricular dysplasia were found. Therefore, an implantable cardioverter defibrillator was implanted, after which the patient has had a favorable outcome.

  1. Right ventricular function assessment in single LAD lesion patients ...

    African Journals Online (AJOL)

    Rania Gaber

    2015-10-09

    Oct 9, 2015 ... Doppler method in patients with single LAD lesion. Methods: The patient group was ... Results: The right ventricular tissue Doppler parameters (Sm, E, A, E/A ratio, IVA, E/E00) of the patients group were significantly .... cardial interaction effect of tethered LV anterior myocardium. Mittal et al. reported that Left ...

  2. Potentiation of the isoproterenol-induced net /sup 45/Ca uptake into the ventricular myocardium of rats by means of 9. cap alpha. -fluorocortisoleacetate, dihydrotachysterole or NaH/sub 2/PO/sub 4/. Cancelling of the potentiation by organic Ca/sup 2 +/ antagonists or K/sup +/ and Mg/sup 2 +/ ions

    Energy Technology Data Exchange (ETDEWEB)

    Hein, R

    1974-01-01

    Myocardial necroses resembling infarctions as well as disseminated myocardial necroses can be induced in rats by high doses of isoprotenerol which effects a maximum stimulation of the decomposition of energy-rich phosphate. This leads to an isoprotenerol-induced increase of the transmembranous Ca/sup + +/ influx, flooding the myocardium with Ca/sup + +/ ions. It is these Ca/sup + +/ ions which then trigger the break-down of the ATP and creatine phosphate fractions by activating the myofibrit-ATPase and impairing the mitochondrial function. It seems that physiological Ca/sup + +/ antagonists such as K/sup +/- or Mg/sup + +/-salts counteract the loss of energy-rich phosphate, thus preventing necroses. A new group of organic Ca/sup + +/ antagonists (verapamil, substance D 600, prenylamine) appears to be even more effective in this respect. Given in appropriate doses, these substances may prevent the isoprotenerol-induced Ca/sup + +/ flooding of the myocardium to a large extent, so that a break-down of the ATP and creatine phosphate fractions is avoided. On the other hand, the isoprotenerol-induced increase of the Ca/sup + +/ influx may be further potentiated by a preliminary treatment of the animals with 9..cap alpha..-fluorocortisoleacetate, dihydrotachysterole or NaH/sub 2/PO/sub 4/. This results in an extreme loss of energy-rich phosphate from the myocardium with excessive enhancement of necrosis production. The findings suggest that - unrecognized so far - Ca/sup + +/ ions play a key role in the generation of myocardial necroses: the present assumption, according to which increased Ca/sup + +/ uptake into damaged myocardial fibres is only a result - or at the most an accompanying symptom - of necrosis can thus no longer be considered valid.

  3. What is the clinical significance of ventricular mural antagonism?

    DEFF Research Database (Denmark)

    Lunkenheimer, Paul P; Niederer, Peter; Stephenson, Robert S

    2018-01-01

    alignment, thus deviating from the prevailing tangential orientation. Upon contraction, they produce, in addition to a tangential force, a radial force component that counteracts ventricular constriction and aids widening of the ventricular cavity. In experimental studies, we have provided evidence...... for the existence of such forces, which are auxotonic in nature. This is in contrast to the tangentially aligned myocytes that produce constrictive forces, which are unloading in nature. The ventricular myocardium is, therefore, able to function in an antagonistic fashion, with the prevailing constrictive forces...

  4. Advanced quantitative echocardiography in arrhythmogenic right ventricular cardiomyopathy

    DEFF Research Database (Denmark)

    Kjaergaard, Jesper; Hastrup Svendsen, Jesper; Sogaard, Peter

    2007-01-01

    BACKGROUND: Arrhythmogenic right ventricular (RV) cardiomyopathy (ARVC) is a regional disease of the RV myocardium with variable degrees of left ventricular involvement. Three-dimensional echocardiography and Doppler tissue imaging (DTI) are new echocardiographic modalities for the evaluation......, patients with ARVC had a decreased RV ejection fraction (0.47 +/- 0.08 vs 0.53 +/- 0.05, P vs 15.1 +/- 3.7 cm/s, P left ventricle (7.0 +/- 2.6 vs 9.5 +/- 1.9 cm/s, P ... of the longitudinal motility appears to be a sensitive marker of preclinical left ventricular involvement....

  5. Detection of the myocardium ischemia in scintigraphy

    International Nuclear Information System (INIS)

    Faraggi, M.; Pierquet-Ghazzar, N.; Maunoury, C.

    2005-01-01

    The myocardium scintigraphy (SPECT) gives excellent elements of prognosis allowing to select at the best, the patients having a revascularization, and then an angiography examination. It appears complementary of the coronaries tree imaging and should (in theory) be practised in first in an organisation chart of taking over. In the search of practicable myocardium, the PET with 18 FDG, although being competitive, is more and more forsaken to the MRI profit. In retaliation, the PET with 82 Rb with test of pharmacology stimulation could develop in detection of coronaries disease. (N.C.)

  6. Archetype, adaptation and the mammalian heart

    NARCIS (Netherlands)

    Meijler, F.L.; Meijler, T.D.

    2011-01-01

    Forty years ago, we started our quest for 'The Holy Grail' of understanding ventricular rate control and rhythm in atrial fibrillation (AF). We therefore studied the morphology and function of a wide range of mammalian hearts. From mouse to whale, we found that all hearts show similar structural

  7. Selective blockade of protein kinase B protects the rat and human myocardium against ischaemic injury

    Science.gov (United States)

    Linares-Palomino, José; Husainy, Muhammad A; Lai, Vien K; Dickenson, John M; Galiñanes, Manuel

    2010-01-01

    Protein kinase B (PKB/Akt) plays a critical role in cell survival but the investigation of its involvement has been limited by the lack of specific pharmacological agents. In this study, using novel PKB inhibitors (VIII and XI), we investigated the role of PKB in cardioprotection of the rat and human myocardium, the location of PKB in relation to mitoKATP channels and p38 mitogen-activated protein kinase (p38 MAPK), and whether the manipulation of PKB can overcome the unresponsiveness to protection of the diabetic myocardium. Myocardial slices from rat left ventricle and from the right atrial appendage of patients undergoing elective cardiac surgery were subjected to 90 min ischaemia/120 min reoxygenation at 37°C. Tissue injury was assessed by creatine kinase (CK) released and determination of cell necrosis and apoptosis. The results showed that blockade of PKB activity caused significant reduction of CK release and cell death, a benefit that was as potent as ischaemic preconditioning and could be reproduced by blockade of phosphatidylinositol 3-kinase (PI-3K) with wortmannin and LY 294002. The protection was time dependent with maximal benefit seen when PKB and PI-3K were inhibited before ischaemia or during both ischaemia and reoxygenation. In addition, it was revealed that PKB is located downstream of mitoKATP channels but upstream of p38 MAPK. PKB inhibition induced a similar degree of protection in the human and rat myocardium and, importantly, it reversed the unresponsiveness to protection of the diabetic myocardium. In conclusion, inhibition of PKB plays a critical role in protection of the mammalian myocardium and may represent a clinical target for the reduction of ischaemic injury. PMID:20403980

  8. Characterization of the positive and negative inotropic effects of acetylcholine in the human myocardium

    OpenAIRE

    Du, Xiaoyi; Schoemaker, Regien; Bos, Egbert; Saxena, Pramod Ranjan

    1995-01-01

    textabstractIn the human isolated myocardium, acetylcholine (10−9 to 10−3 M) elicited a biphasic inotropic effect (a decrease in the lower and an increase in the higher concentration range) in atrial and a positive inotropic effect in ventricular trabeculae. However, under conditions of raised contractility achieved by exposure to noradrenaline (10−5 M), only negative inotropic effects were observed in both atria and ventricles. Atropine (10−6 M), but not propranolol (10−6 M), antagonized bot...

  9. Resolving the True Ventricular Mural Architecture

    Directory of Open Access Journals (Sweden)

    Robert S. Stephenson

    2018-06-01

    Full Text Available The precise nature of packing together of the cardiomyocytes within the ventricular walls has still to be determined. The spiraling nature of the chains of interconnected cardiomyocytes has long been recognized. As long ago as the end of the nineteenth century, Pettigrew had emphasized that the ventricular cone was not arranged on the basis of skeletal muscle. Despite this guidance, subsequent anatomists described entities such as “bulbo-spiral muscles”, with this notion of subunits culminating in the suggestion that the ventricular cone could be unwrapped so as to produce a “ventricular myocardial band”. Others, in contrast, had suggested that the ventricular walls were arranged on the basis of “sheets”, or more recently “sheetlets”, with investigators seeking to establishing the angulation of these entities using techniques such as magnetic resonance imaging. Our own investigations, in contrast, have shown that the cardiomyocytes are aggregated together within the supporting fibrous matrix so as to produce a three-dimensional myocardial mesh. In this review, we summarize the previous accounts, and provide the anatomical evidence we have thus far accumulated to support the model of the myocardial mesh. We show how these anatomic findings underscore the concept of the myocardial mesh functioning in antagonistic fashion. They lend evidence to support the notion that the ventricular myocardium works as a muscular hydrostat.

  10. Distinct patterns of constitutive phosphodiesterase activity in mouse sinoatrial node and atrial myocardium.

    Directory of Open Access Journals (Sweden)

    Rui Hua

    Full Text Available Phosphodiesterases (PDEs are critical regulators of cyclic nucleotides in the heart. In ventricular myocytes, the L-type Ca(2+ current (I(Ca,L is a major target of regulation by PDEs, particularly members of the PDE2, PDE3 and PDE4 families. Conversely, much less is known about the roles of PDE2, PDE3 and PDE4 in the regulation of action potential (AP properties and I(Ca,L in the sinoatrial node (SAN and the atrial myocardium, especially in mice. Thus, the purpose of our study was to measure the effects of global PDE inhibition with Isobutyl-1-methylxanthine (IBMX and selective inhibitors of PDE2, PDE3 and PDE4 on AP properties in isolated mouse SAN and right atrial myocytes. We also measured the effects of these inhibitors on I(Ca,L in SAN and atrial myocytes in comparison to ventricular myocytes. Our data demonstrate that IBMX markedly increases spontaneous AP frequency in SAN myocytes and AP duration in atrial myocytes. Spontaneous AP firing in SAN myocytes was also increased by the PDE2 inhibitor erythro-9-[2-hydroxy-3-nonyl] adenine (EHNA, the PDE3 inhibitor milrinone (Mil and the PDE4 inhibitor rolipram (Rol. In contrast, atrial AP duration was increased by EHNA and Rol, but not by Mil. IBMX also potently, and similarly, increased I(Ca,L in SAN, atrial and ventricular myocytes; however, important differences emerged in terms of which inhibitors could modulate I(Ca,L in each myocyte type. Consistent with our AP measurements, EHNA, Mil and Rol each increased I(Ca,L in SAN myocytes. Also, EHNA and Rol, but not Mil, increased atrial I(Ca,L. In complete contrast, no selective PDE inhibitors increased I(Ca,L in ventricular myocytes when given alone. Thus, our data show that the effects of selective PDE2, PDE3 and PDE4 inhibitors are distinct in the different regions of the myocardium indicating important differences in how each PDE family constitutively regulates ion channel function in the SAN, atrial and ventricular myocardium.

  11. Stereological Cell Morphometry In Right Atrium Myocardium Of Primates

    Science.gov (United States)

    Mandarim-De-Lacerda, Carlos A...; Hureau, Jacques

    1986-07-01

    The mechanism by which the cardiac impulse is propagated in normal hearts from its origin in the sinus node to the atrio-ventricular node has not been agreed on fully. We studied the "internodal posterior tract" through the crista terminalis by light microscopy and stereological morphometry. The hearts of 12 Papio cynocephalus were perfused , after sacrifice,with phosphate-buffered formol saline. The regions of the crista terminalis (CT), interatrial septum (IAS), atrioventricular bundle (AVB) and interventricular septum (IVS) were cut off and embedded in paraplast and sectioned (10 4m). The multipurpose test system M 42 was superimposed over the photomicrographs (1,890 points test, ESR = 2%) to the stereological computing. The quantitative results show that the cells from CT were more closely relationed with IAS cells than others cells (IVS and AVB cells). This results are not a morphological evidence to establish the specificity of the "internodal posterior tract". The cellular arrangement and anatomical variation in CT myocardium is very important.

  12. Miocárdio hibernante: uma realidade clínica Hibernant myocardium: a clinical reality

    Directory of Open Access Journals (Sweden)

    J.A. Marin-Neto

    1997-12-01

    Full Text Available O conceito da hibernação miocárdica implica a ocorrência de disfunção ventricular crônica, potencialmente reversível, causada por dissinergia regional, dependente de isquemia prolongada. Não tem fisiopatologia elucidada, em parte porque não existem modelos experimentais satisfatórios para seu estudo. Diversos métodos são capazes de demonstrar viabilidade miocárdica nas regiões que não exibem capacidade contrátil basal. O desmascaramento da hibernação nesses territórios pode ser feito mediante demonstração de reserva contrátil, de funcionamento normal da membrana celular, ou de metabolismo preservado. A correta identificação de miocárdio hibernante reveste-se de especial significado clínico, por suas implicações prognósticas quanto a intervenções de revascularização miocárdica, destinadas a reabilitar a função ventricular em muitos pacientes coronariopatas crônicos.Myocardial hibernation is believed to occur in ventricular dyssynergic regions chronically deprived of coronary flow enough to warrant the preservation of contractile function. Pathophysiology of this condition remains largely unclear, mainly because good experimental models for its study are still lacking. Various methods can be clinically employed to detect hibernation in patients with chronic ventricular dysfunction. These methods use the principle of unmasking contractile reserve, or are based on the demonstration of preserved membrane function or myocardium metabolism in the dyssynergic regions. The correct identification of viable hibernating myocardium is crucial in the process of deciding which coronary disease patients would potentially benefit from revascularization procedures.

  13. Healthy aging and myocardium: A complicated process with various effects in cardiac structure and physiology.

    Science.gov (United States)

    Nakou, E S; Parthenakis, F I; Kallergis, E M; Marketou, M E; Nakos, K S; Vardas, P E

    2016-04-15

    It is known that there is an ongoing increase in life expectancy worldwide, especially in the population older than 65years of age. Cardiac aging is characterized by a series of complex pathophysiological changes affecting myocardium at structural, cellular, molecular and functional levels. These changes make the aged myocardium more susceptible to stress, leading to a high prevalence of cardiovascular diseases (heart failure, atrial fibrillation, left ventricular hypertrophy, coronary artery disease) in the elderly population. The aging process is genetically programmed but modified by environmental influences, so that the rate of aging can vary widely among people. We summarized the entire data concerning all the multifactorial changes in aged myocardium and highlighting the recent evidence for the pathophysiological basis of cardiac aging. Keeping an eye on the clinical side, this review will explore the potential implications of the age-related changes in the clinical management and on novel therapeutic strategies potentially deriving from the scientific knowledge currently acquired on cardiac aging process. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  14. The helical ventricular myocardial band of Torrent-Guasp.

    Science.gov (United States)

    Kocica, Mladen J; Corno, Antonio F; Lackovic, Vesna; Kanjuh, Vladimir I

    2007-01-01

    We live in an era of substantial progress in understanding myocardial structure and function at genetic, molecular, and microscopic levels. Yet, ventricular myocardium has proven remarkably resistant to macroscopic analyses of functional anatomy. Pronounced and practically indefinite global and local structural anisotropy of its fibers and other ventricular wall constituents produces electrical and mechanical properties that are nonlinear, anisotropic, time varying, and spatially inhomogeneous. The helical ventricular myocardial band of Torrent-Guasp is a revolutionary new concept in understanding global, 3-dimensional, functional architecture of the ventricular myocardium. This concept defines the principal, cumulative vectors, integrating the tissue architecture (ie, form) and net forces developed (ie, function) within the ventricular mass. The primary purpose of this review is to emphasize the importance of this concept, in the light of collaborative efforts to establish an integrative approach, defining ventricular form and function by linking across multiple scales of biological organization, as explained in the ongoing Physiome project. Because one of the most important scientific missions in this century is integration of basic research with clinical medicine, we believe that this knowledge is not of merely academic importance, but is also the essential prerequisite in clinical evaluation and treatment of different heart diseases.

  15. Effects of acute and chronic uremia on active cation transport in rat myocardium

    Energy Technology Data Exchange (ETDEWEB)

    Druml, W.; Kelly, R.A.; England, B.K.; O' Hara, D.S.; Mitch, W.E. (Brigham and Women' s Hospital, Boston, MA (USA))

    1990-12-01

    As abnormalities of active cation transport could contribute to the genesis of uremic cardiomyopathy, we investigated myocardial sodium pump function in rats with acute renal failure (ARF) and with a model of experimental chronic renal failure (CRF) that has metabolic similarities to advanced chronic uremia in humans. CRF rats were hypertensive and had left ventricular hypertrophy (33% higher heart:body weight ratio; P less than 0.01) at four weeks compared to pair-fed sham-operated rats. Importantly, both ouabain- and furosemide-sensitive 86Rb uptake rates were unchanged in left ventricular myocardial slices from CRF, and the intracellular sodium concentration was not different from that of control rats even though skeletal muscle sodium was increased, as we found previously. Insulin-stimulated, ouabain-sensitive 86Rb influx was also preserved. There also were no abnormalities in myocardium cation transport in rats with ARF. However, (3H)ouabain binding was decreased 45% in CRF rats (P less than 0.01); it was unchanged in acute uremia. Decreased ouabain binding in chronic uremia was due entirely to fewer low affinity (3H)ouabain binding sites (the binding affinity for ouabain was unaffected). We conclude that in chronic, (but not acute) renal failure, sodium pump number is reduced in myocardium but intracellular sodium is unchanged and active cation flux rates are maintained. These results emphasize that in rats with chronic uremia, intracellular sodium homeostasis is preserved in myocardium, despite the presence of marked abnormalities of active cation transport in skeletal muscle that are characteristic of chronic uremia.

  16. Pre- and post-synaptic sympathetic function in human hibernating myocardium

    Energy Technology Data Exchange (ETDEWEB)

    John, Anna S.; Pepper, John R.; Dreyfus, Gilles D.; Pennell, Dudley J. [Imperial College, Hammersmith Hospital, National Heart and Lung Institute, London (United Kingdom); Mongillo, Marco; Khan, Muhammad T. [Imperial College, Hammersmith Hospital, Medical Research Council Clinical Sciences Centre, London (United Kingdom); Depre, Christophe [University of Medicine and Dentistry New Jersey, Cardiovascular Research Institute, Department of Cell Biology and Molecular Medicine, New Jersey, NJ (United States); University of Medicine and Dentistry New Jersey, Cardiovascular Research Institute, Department of Medicine, New Jersey, NJ (United States); Rimoldi, Ornella E. [Imperial College, Hammersmith Hospital, National Heart and Lung Institute, London (United Kingdom); Imperial College, Hammersmith Hospital, Medical Research Council Clinical Sciences Centre, London (United Kingdom); New York Medical College, Cardiovascular Research Institute, Department of Medicine, Valhalla, NY (United States); Camici, Paolo G. [Imperial College, Hammersmith Hospital, National Heart and Lung Institute, London (United Kingdom); Imperial College, Hammersmith Hospital, Medical Research Council Clinical Sciences Centre, London (United Kingdom)

    2007-12-15

    Impaired pre-synaptic noradrenaline uptake-1 mechanism has been reported in a swine model of hibernating myocardium (HM). To ascertain whether adrenergic neuroeffector abnormalities are present in human HM, we combined functional measurements in vivo using cardiovascular magnetic resonance (CMR) and positron emission tomography (PET) to assess pre- and post-synaptic sympathetic function. Twelve patients with coronary artery disease and chronic left ventricular (LV) dysfunction underwent CMR at baseline and 6 months after bypass for assessment of regional and global LV function and identification of segments with reversible dysfunction. Before surgery, myocardial noradrenaline uptake-1 ([{sup 11}C]meta-hydroxy-ephedrine; HED) and {beta}-adrenoceptor ({beta}-AR) density ([{sup 11}C]CGP-12177) were measured with PET. Patient PET data were compared with those in 18 healthy controls. The volume of distribution (V{sub d}) of HED in HM (47.95{+-}28.05 ml/g) and infarcted myocardium (42.69{+-}25.76 ml/g) was significantly reduced compared with controls (66.09{+-}14.48 ml/g). The V{sub d} of HED in normal myocardium (49.93{+-}20.48 ml/g) of patients was also lower than that in controls and the difference was close to statistical significance (p=0.06). Myocardial {beta}-AR density was significantly lower in HM (5.49{+-}2.35 pmol/g), infarcted (4.82{+-}2.61 pmol/g) and normal (5.86{+-}1.81 pmol/g) segments of patients compared with healthy controls (8.61{+-}1.32 pmol/g). Noradrenaline uptake-1 mechanism and {beta}-AR density are reduced in the myocardium of patients with chronic LV dysfunction and evidence of HM. The increased sympathetic activity to the heart in these patients is a generalised rather than regional phenomenon which is likely to contribute to the remodelling process of the whole LV rather than playing a causative role in HM. (orig.)

  17. Ventricular tachycardia in ischemic heart disease substrates

    Directory of Open Access Journals (Sweden)

    Olujimi A. Ajijola

    2014-01-01

    This review will discuss the central role of the ischemic heart disease substrate in the development MMVT. Electrophysiologic characterization of the post-infarct myocardium using bipolar electrogram amplitudes to delineate scar border zones will be reviewed. Functional electrogram determinants of reentrant circuits such as isolated late potentials will be discussed. Strategies for catheter ablation of reentrant ventricular tachycardia, including structural and functional targets will also be examined, as will the role of the epicardial mapping and ablation in the management of recurrent MMVT.

  18. Cellular Plasticity in the Diabetic Myocardium

    Science.gov (United States)

    2017-09-01

    imaging ( MRI ) suggests that many patients with PH exhibit evidence of right ventricular fibrosis.36 Histological studies have demonstrated increased...derived from pharmacologic inhibition experiments. In a rabbit model of pul- monary artery banding and in a model of monocrotaline-induced pul- monary...thus triggering a fibrotic response52. Pharmacologic inhibition experiments have suggested an important role for the RAAS in right ventricular dys

  19. Role of Notch signaling in the mammalian heart

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, X.L.; Liu, J.C. [Department of Cardiac Surgery, The First Affiliated Hospital, Nanchang University, Donghu District, Nanchang, Jiangxi (China)

    2013-12-12

    Notch signaling is an evolutionarily ancient, highly conserved pathway important for deciding cell fate, cellular development, differentiation, proliferation, apoptosis, adhesion, and epithelial-to-mesenchymal transition. Notch signaling is also critical in mammalian cardiogenesis, as mutations in this signaling pathway are linked to human congenital heart disease. Furthermore, Notch signaling can repair myocardial injury by promoting myocardial regeneration, protecting ischemic myocardium, inducing angiogenesis, and negatively regulating cardiac fibroblast-myofibroblast transformation. This review provides an update on the known roles of Notch signaling in the mammalian heart. The goal is to assist in developing strategies to influence Notch signaling and optimize myocardial injury repair.

  20. Mitochondrial complex III defects contribute to inefficient respiration and ATP synthesis in the myocardium of Trypanosoma cruzi-infected mice.

    Science.gov (United States)

    Wen, Jian-Jun; Garg, Nisha Jain

    2010-01-01

    In this study, we conducted a thorough analysis of mitochondrial bioenergetic function as well as the biochemical and molecular factors that are deregulated and contribute to compromised adenosine triphosphate (ATP) production in the myocardium during Trypanosoma cruzi infection. We show that ADP-stimulated state 3 respiration and ATP synthesis supported by pyruvate/malate (provides electrons to complex I) and succinate (provides electrons to complex II) substrates were significantly decreased in left ventricular tissue and isolated cardiac mitochondria of infected mice. The decreased mitochondrial ATP synthesis in infected murine hearts was not a result of uncoupling between the electron-transport chain and oxidative phosphorylation and decreased availability of the intermediary metabolites (e.g., NADH). The observed decline in the activities of complex-I, -IV, and -V was not physiologically relevant and did not contribute to compromised respiration and ATP synthesis in infected myocardium. Instead, complex III activity was decreased above the threshold level and contributed to respiratory-chain inefficiency and the resulting decline in mitochondrial ATP synthesis in infected myocardium. The loss in complex III activity occurred as a consequence of cytochrome b depletion. Treatment of infected mice with phenyl-alpha-tert-butyl nitrone (PBN, antioxidant) was beneficial in preserving the mtDNA-encoded cytochrome b expression, and subsequently resulted in improved complex III activity, mitochondrial respiration, and ATP production in infected myocardium. Overall, we provide novel data on the mechanism(s) involved in cardiac bioenergetic inefficiency during T. cruzi infection.

  1. Mammalian sleep

    Science.gov (United States)

    Staunton, Hugh

    2005-05-01

    This review examines the biological background to the development of ideas on rapid eye movement sleep (REM sleep), so-called paradoxical sleep (PS), and its relation to dreaming. Aspects of the phenomenon which are discussed include physiological changes and their anatomical location, the effects of total and selective sleep deprivation in the human and animal, and REM sleep behavior disorder, the latter with its clinical manifestations in the human. Although dreaming also occurs in other sleep phases (non-REM or NREM sleep), in the human, there is a contingent relation between REM sleep and dreaming. Thus, REM is taken as a marker for dreaming and as REM is distributed ubiquitously throughout the mammalian class, it is suggested that other mammals also dream. It is suggested that the overall function of REM sleep/dreaming is more important than the content of the individual dream; its function is to place the dreamer protagonist/observer on the topographical world. This has importance for the developing infant who needs to develop a sense of self and separateness from the world which it requires to navigate and from which it is separated for long periods in sleep. Dreaming may also serve to maintain a sense of ‘I’ness or “self” in the adult, in whom a fragility of this faculty is revealed in neurological disorders.

  2. Pathological prolongation of action potential duration as a cause of the reduced alpha-adrenoceptor-mediated negative inotropy in streptozotocin-induced diabetic mice myocardium.

    Science.gov (United States)

    Kanae, Haruna; Hamaguchi, Shogo; Wakasugi, Yumi; Kusakabe, Taichi; Kato, Keisuke; Namekata, Iyuki; Tanaka, Hikaru

    2017-11-01

    Effect of pathological prolongation of action potential duration on the α-adrenoceptor-mediated negative inotropy was studied in streptozotocin-induced diabetic mice myocardium. In streptozotocin-treated mouse ventricular myocardium, which had longer duration of action potential than that in control mice, the negative inotropic response induced by phenylephrine was smaller than that in control mice. 4-Aminopyridine prolonged the action potential duration and decreased the negative inotropy in control mice. Cromakalim shortened the action potential duration and increased the negative inotropy in streptozotocin-treated mice. These results suggest that the reduced α-adrenoceptor-mediated inotropy in the diabetic mouse myocardium is partly due to its prolonged action potential. Copyright © 2017 The Authors. Production and hosting by Elsevier B.V. All rights reserved.

  3. Angiographic determination of the left-ventricular myocardial volume with the help of digital image processing

    International Nuclear Information System (INIS)

    Radtke, W.

    1981-01-01

    In this paper, digital image processing could for the first time be introduced as a new method to screen the myocardium in the left-ventricular angiocardiography. The method makes a reliable quantitative determination of the muscle mass of the left ventricle possible. (orig./MG) [de

  4. Liposome kinetics in infarcted canine myocardium

    International Nuclear Information System (INIS)

    Caride, V.J.; Twickler, J.; Zaret, B.L.

    1984-01-01

    To study the mechanisms and kinetics of liposome deposition in the region of the experimental myocardial infarction, the myocardial distribution of positive and negative liposomes was determined as a function of regional myocardial blood flow and time after administration. The study was performed in dogs at 1 and 24 h following experimental myocardial infarction. Twenty-four hours after coronary artery occlusion, the initial myocardial distribution of positive and negative liposomes (2 min) is directly proportional to regional myocardial blood flow. With time, there is reduction of the radiotracer associated with negative liposomes from all myocardial regions (p less than 0.01). In contrast, in areas of moderate and severe blood flow reduction, there is progressive accumulation of tracers entrapped or incorporated in positive liposomes. This increment becomes significant in 120 min (p less than 0.005). Similar findings are observed in studies performed 1 h after coronary artery occlusion. Dual-label liposomes [( 3 H]cholesterol and [99mTc]diethylenetriamine pentaacetic acid) were used to study the integrity of liposomes in normal and ischemic myocardium. Significant dissociation of the aqueous and lipid labels of positive liposomes is observed 1 h following coronary artery occlusion. In the 24-h myocardial infarction model, dissociation of the aqueous and lipid labels in ischemic myocardium is also observed. This phenomenon is more pronounced with positive than with negative liposomes (p less than 0.02)

  5. Tropical diseases of the myocardium: a review

    Directory of Open Access Journals (Sweden)

    Groom ZC

    2017-04-01

    Full Text Available Zoe C Groom,1 Aristotle D Protopapas,2 Vasileios Zochios3,4 1Costello Medical Consulting Limited, Cambridge, 2Department of Surgery, Division of Surgery and Cancer, Imperial College London, London, 3Department of Intensive Care Medicine, Queen Elizabeth Hospital Birmingham, University Hospitals Birmingham NHS Foundation Trust, 4College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK Abstract: Cardiovascular diseases are widely distributed throughout the world. Human parasitic infections are ubiquitous. Tropical parasites are increasingly recognized as causes of cardiovascular diseases. In this review, we address the most frequently reported parasites that directly infect the myocardium, including Trypanosoma cruzi, the protozoal causative agent of American trypanosomiasis (Chagas disease, and Taenia solium, the cestode causative agent of taeniasis and cysticercosis. We also discuss tropical endomyocardial fibrosis, trichinellosis and schistosomiasis. Health systems, attitudes, the perceptions of both patients and physicians as well as socioeconomic factors should all be explored and recognized as crucial factors for improving the control of cardiovascular diseases in the tropics. Clinicians throughout the world must remain aware of imported parasites as potential causes of cardiac diseases. Keywords: cardiomyopathy, Chagas disease, myocardium, parasitic infection, tropical infections

  6. Angiogenesis with intramyocardial administration of basic fibroblast growth factor in canine ischemic myocardium

    International Nuclear Information System (INIS)

    Sun Lijun; Liu Ying; Zhao Haitao; Huan Yi; Ge Yali; Gao Fabao

    2004-01-01

    .6, 147.3 ± 11.6; on the 10 th day: 125.0 ± 12.1, 182.7 ± 14.0; on the 17 th day: 124.7 ± 14.5, 223.7 ± 19.9). Conclusion: Intramyocardial administration of basic fibroblast growth factor is useful in increasing the growth of microvessels, decreasing the size of the infarcted myocardium, and improving left ventricular function in acute myocardial infarction

  7. Substrate use in ischemic and reperfused canine myocardium: quantitative considerations

    International Nuclear Information System (INIS)

    Myears, D.W.; Sobel, B.E.; Bergmann, S.R.

    1987-01-01

    The patterns of use of substrate in reperfused myocardium are not yet well elucidated, and their delineation is essential for adequate interpretation of results of analyses performed after positron emission tomography with labeled substrates to differentiate normal from abnormal heart muscle. Accordingly, in open-chest, anesthetized dogs the authors measured glucose and fatty acid utilization in normal, ischemic, and reperfused myocardium and assessed the contributions of metabolism of each substrate to overall oxidative metabolism. Intracoronary [ 3 H]glucose and [ 14 C]palmitate were administered in five control dogs, eight dogs subjected to 1 h of coronary occlusion, and nine dogs subjected to reperfusion after 1 h of ischemia. Regional coronary venous blood samples were assayed sequentially. In reperfused myocardium, utilization of glucose was 103% greater than that in ischemic and 273% greater than in normal myocardium. Utilization of fatty acid during reperfusion, although greater than that in ischemic myocardium, was significantly less than that in normal myocardium despite restoration of flow to 80% of control values. Despite diminished net uptake of fatty acid, oxidation of fatty acid accounted for 63% of total oxygen consumption in reperfused myocardium. These studies indicate that canine myocardium reperfused after 1 h of ischemia exhibits enhanced uptake of glucose and impaired utilization of palmitate. Nevertheless, palmitate continues to comprise the substrate primarily utilized for oxidative metabolism

  8. Measurement of infarct size and percentage myocardium infarcted in a dog preparation with single photon-emission computed tomography, thallium-201, and indium 111-monoclonal antimyosin Fab

    International Nuclear Information System (INIS)

    Johnson, L.L.; Lerrick, K.S.; Coromilas, J.

    1987-01-01

    Single photon-emission tomography (SPECT) and indium 111-labeled monoclonal antimyosin Fab fragments were used to measure myocardial infarct size in 12 dogs, six subjected to balloon catheter-induced coronary artery occlusion for 6 hr (late reperfusion) and six subjected to occlusion with reperfusion at 2 hr (early reperfusion). Tomographic imaging was performed 24 hr after the intravenous injection of labeled Fab fragments with the use of a dual-head SPECT camera with medium-energy collimators. Immediately after the first tomographic scan, thallium-201 was injected into nine of 12 dogs and imaging was repeated. Estimated infarct size in grams was calculated from transaxially reconstructed, normalized, and background-corrected indium SPECT images with the use of a threshold technique for edge detection. Estimated noninfarcted myocardium in grams was calculated from obliquely reconstructed thallium SPECT images by a similar method. The animals were killed and infarct size in grams and true infarct size as a percentage of total left ventricular myocardial volume were measured by triphenyl tetrazolium chloride staining. Estimated infarct size from indium SPECT images showed an excellent correlation with true infarct size (r = .95, SEE = 4.1 g). Estimated percentage myocardium infarcted was calculated by dividing estimated infarct size from indium images by the sum of estimated infarct size plus estimated noninfarcted myocardium obtained from thallium images. Correlation between the estimated percentage of myocardium infarcted and true percentage of myocardium infarcted was excellent

  9. Coupling of the Functional Stability of Rat Myocardium and Activity of Lipid Peroxidation in Combined Development of Postinfarction Remodeling and Diabetes Mellitus

    Directory of Open Access Journals (Sweden)

    S. A. Afanasiev

    2016-01-01

    Full Text Available Coupling of the functional stability of rat myocardium and activity of lipid peroxidation processes in combined development of postinfarction remodeling and diabetes mellitus has been studied. The functional stability of myocardium was studied by means of the analysis of inotropic reaction on extrasystolic stimulus, the degree of left ventricular hypertrophy, and the size of scar zone. It was shown that in combined development of postinfarction cardiac remodeling of heart (PICR with diabetes mellitus (DM animal body weight decreased in less degree than in diabetic rats. Animals with combined pathology had no heart hypertrophy. The amplitude of extrasystolic contractions in rats with PICR combined with DM had no differences compared to the control group. In myocardium of rats with PICR combined with DM postextrasystolic potentiation was observed in contrast with the rats with PICR alone. The rats with combined pathology had the decreased value of TBA-active products. Thus, the results of study showed that induction of DM on the stage of the development of postinfarction remodeling increases adaptive ability of myocardium. It is manifested in inhibition of increase of LPO processes activity and maintaining of force-interval reactions of myocardium connected with calcium transport systems of sarcoplasmic reticulum of cardiomyocytes.

  10. Activation patterns of Purkinje fibers during long-duration ventricular fibrillation in an isolated canine heart model.

    Science.gov (United States)

    Tabereaux, Paul B; Walcott, Greg P; Rogers, Jack M; Kim, Jong; Dosdall, Derek J; Robertson, Peter G; Killingsworth, Cheryl R; Smith, William M; Ideker, Raymond E

    2007-09-04

    The roles of Purkinje fibers (PFs) and focal wave fronts, if any, in the maintenance of ventricular fibrillation (VF) are unknown. If PFs are involved in VF maintenance, it should be possible to map wave fronts propagating from PFs into the working ventricular myocardium during VF. If wave fronts ever arise focally during VF, it should be possible to map them appearing de novo. Six canine hearts were isolated, and the left main coronary artery was cannulated and perfused. The left ventricular cavity was exposed, which allowed direct endocardial mapping of the anterior papillary muscle insertion. Nonperfused VF was induced, and 6 segments of data, each 5 seconds long, were analyzed during 10 minutes of VF. During 36 segments of data that were analyzed, 1018 PF or focal wave fronts of activation were identified. In 534 wave fronts, activation was mapped propagating from working ventricular myocardium to PF. In 142 wave fronts, activation was mapped propagating from PF to working ventricular myocardium. In 342 wave fronts, activation was mapped arising focally. More than 1 of these 3 patterns could occur in the same wave front. PFs are highly active throughout the first 10 minutes of VF. In addition to retrograde propagation from the working ventricular myocardium to PFs, antegrade propagation occurs from PFs to working ventricular myocardium, which suggests PFs are important in VF maintenance. Prior plunge needle recordings in dogs indicate activation propagates from the endocardium toward the epicardium after 1 minute of VF, which suggests that focal sites on the endocardium may represent foci and not breakthrough. If so, in addition to reentry, abnormal automaticity or triggered activity may also occur during VF.

  11. Selective Retrograde Venous Revascularization of the Myocardium when PCI or CABG Is Impossible: Investigation in a Porcine Model

    DEFF Research Database (Denmark)

    Møller, Christian H; Nørgaard, Martin A; Gøtze, Jens P

    2008-01-01

    We investigated the possibility of nourishing the myocardium through selective retrograde coronary venous bypass grafting (CVBG) with an off-pump technique and evaluated various methods of monitoring the physiological effects of this procedure. In a porcine model, the left internal mammary artery...... tension decreased, but with time some recovery was seen. Cardiac troponin T was elevated. Histological analysis showed ischemic changes. In control pigs, microdialysis was performed for 1.5 hours up to LAD artery ligation, after which all pigs died in ventricular fibrillation arrest. No increase...

  12. Arrhythmogenic right ventricular cardiomyopathy: contribution of different electrocardiographic techniques.

    Science.gov (United States)

    Moreira, Davide; Delgado, Anne; Marmelo, Bruno; Correia, Emanuel; Gama, Pedro; Pipa, João; Nunes, Luís; Santos, Oliveira

    2014-04-01

    Arrhythmogenic right ventricular cardiomyopathy, also known as arrhythmogenic right ventricular dysplasia, is a condition in which myocardium is replaced by fibrous or fibrofatty tissue, predominantly in the right ventricle. It is clinically characterized by potentially lethal ventricular arrhythmias, and is a leading cause of sudden cardiac death. Its prevalence is not known exactly but is estimated at approximately 1:5000 in the adult population. Diagnosis can be on the basis of structural and functional alterations of the right ventricle, electrocardiographic abnormalities (including depolarization and repolarization alterations and ventricular arrhythmias) and family history. Diagnostic criteria facilitate the recognition and interpretation of non-specific clinical features of this disease. The authors present a case in which the diagnosis of arrhythmogenic right ventricular cardiomyopathy was prompted by the suspicion of right ventricular disease on transthoracic echocardiography. This was confirmed by detection of epsilon waves on analysis of the ECG, which generally go unnoticed but in this case were the key to the diagnosis. Their presence was also shown by non-conventional ECG techniques such as modified Fontaine ECG. The course of the disease culminated in the occurrence of ventricular tachycardia, which prompted placement of an implantable cardioverter-defibrillator. Copyright © 2013 Sociedade Portuguesa de Cardiologia. Published by Elsevier España. All rights reserved.

  13. Development of an in vivo method for determining material properties of passive myocardium

    Directory of Open Access Journals (Sweden)

    Espen Remme

    2004-10-01

    Full Text Available Calculation of mechanical stresses and strains in the left ventricular (LV myocardium by the finite element (FE method relies on adequate knowledge of the material properties of myocardial tissue. In this paper we present a model-based estimation procedure to characterize the stress-strain relationship in passive LV myocardium. A 3D FE model of the LV myocardium was used, which included morphological fiber and sheet structure and a nonlinear orthotropic constitutive law with different stiffness in the fiber, sheet and sheet-normal directions. The estimation method was based on measured wall strains. We analyzed the method's ability to estimate the material parameters by generating a set of synthetic strain data by simulating the LV inflation phase with known material parameters. In this way we were able to verify the correctness of the solution and to analyze the effects of measurement and model error on the solution accuracy and stability. A sensitivity analysis was performed to investigate the observability of the material parameters and to determine which parameters to estimate. The results showed a high degree of coupling between the parameters governing the stiffness in each direction. Thus, only one parameter in each of the three directions was estimated. For the tested magnitudes of added noise and introduced model errors, the resulting estimated stress-strain characteristics in the fiber and sheet directions converged with good accuracy to the known relationship. The sheet-normal stress-strain relationship had a higher degree of uncertainty as more noise was added and model error was introduced.

  14. Interaction of metabolic and respiratory acidosis with α and β-adrenoceptor stimulation in rat myocardium.

    Science.gov (United States)

    Biais, Matthieu; Jouffroy, Romain; Carillion, Aude; Feldman, Sarah; Jobart-Malfait, Aude; Riou, Bruno; Amour, Julien

    2012-12-01

    The effects of acute respiratory versus metabolic acidosis on the myocardium and their consequences on adrenoceptor stimulation remain poorly described. We compared the effects of metabolic and respiratory acidosis on inotropy and lusitropy in rat myocardium and their effects on the responses to α- and β-adrenoceptor stimulations. The effects of acute respiratory and metabolic acidosis (pH 7.10) and their interactions with α and β-adrenoceptor stimulations were studied in isolated rat left ventricular papillary muscle (n=8 per group). Intracellular pH was measured using confocal microscopy and a pH-sensitive fluorophore in isolated rat cardiomyocytes. Data are mean percentages of baseline±SD. Respiratory acidosis induced more pronounced negative inotropic effects than metabolic acidosis did both in isotonic (45±3 versus 63±6%, Prespiratory or metabolic acidosis. The inotropic response to β-adrenergic stimulation was impaired only in metabolic acidosis (137±12 versus 200±33%, Pacidosis. The lusitropic response to β-adrenergic stimulation was not modified by respiratory or metabolic acidosis. Acute metabolic and respiratory acidosis induce different myocardial effects related to different decreases in intracellular pH. Only metabolic acidosis impairs the positive inotropic effect of β-adrenergic stimulation.

  15. Experimental basis of metabolic imaging of the myocardium with radioiodinated aromatic free fatty acids

    International Nuclear Information System (INIS)

    Reske, S.N.; Knapp, F.F. Jr.; Winkler, C.

    1986-01-01

    For the investigation of myocardial perfusion and left ventricular pump function, advanced radioisotopic techniques have been established. New developments in radiopharmacology and single-photon emission computed tomography have recently enabled the investigation of parameters of regional energy metabolism in well defined areas of the heart muscle. For this purpose, various iodine ( 123 I)-labeled free fatty acids (FFA) have been synthesized. The diagnostic application of labeled FFA in heart disease may be important, since FFA are the preferred substrates for cardiac energy production at rest in the fasting state. In addition, regional myocardial FFA uptake and regional myocardial blood flow are tightly coupled in normal myocardium with beta-oxidation which is extremely sensitive to oxygen deprivation. This article outlines the basic physiologic pathways of FFA in normal and ischemic myocardium and reviews the results of animal experiments validating the application of these principles for metabolic imaging of the heart by means of the aromatic radioiodinated FFA, 15-(p-iodophenyl)pentadecanoic acid. In addition, the development, physiologic properties, and potential applications of a new generation of 3-methyl-substituted radioiodinated fatty acids that show high myocardial uptake but prolonged retention are discussed. 64 references

  16. Effects of allocryptopine on outward potassium current and slow delayed rectifier potassium current in rabbit myocardium.

    Science.gov (United States)

    Fu, Yi-Cheng; Zhang, Yu; Tian, Liu-Yang; Li, Nan; Chen, Xi; Cai, Zhong-Qi; Zhu, Chao; Li, Yang

    2016-05-01

    Allocryptopine (ALL) is an effective alkaloid of Corydalis decumbens (Thunb.) Pers. Papaveraceae and has proved to be anti-arrhythmic. The purpose of our study is to investigate the effects of ALL on transmural repolarizing ionic ingredients of outward potassium current (I to) and slow delayed rectifier potassium current (I Ks). The monophasic action potential (MAP) technique was used to record the MAP duration of the epicardium (Epi), myocardium (M) and endocardium (Endo) of the rabbit heart and the whole cell patch clamp was used to record I to and I Ks in cardiomyocytes of Epi, M and Endo layers that were isolated from rabbit ventricles. The effects of ALL on MAP of Epi, M and Endo layers were disequilibrium. ALL could effectively reduce the transmural dispersion of repolarization (TDR) in rabbit transmural ventricular wall. ALL decreased the current densities of I to and I Ks in a voltage and concentration dependent way and narrowed the repolarizing differences among three layers. The analysis of gating kinetics showed ALL accelerated the channel activation of I to in M layers and partly inhibit the channel openings of I to in Epi, M and Endo cells. On the other hand, ALL mainly slowed channel deactivation of I Ks channel in Epi and Endo layers without affecting its activation. Our study gives partially explanation about the mechanisms of transmural inhibition of I to and I Ks channels by ALL in rabbit myocardium. These findings provide novel perspective regarding the anti-arrhythmogenesis application of ALL in clinical settings.

  17. Contribution to the study of thallium 201 myocardium scintigraphy

    International Nuclear Information System (INIS)

    Annweiler, Marc.

    1976-01-01

    In this work a new isotope was tested in the field of myocardium scintigraphy: thallium 201. The different radioisotopes used so far in myocardium scintigraphy are reviewed to begin with. The main biological and physical characteristics of thallium and the scintillation camera used for this work are described next. In our opinion thallium 201 owing to its biological behavior similar to that of potassium and to its physical characteristics, appears as one of the better -if not the best- known tracer suitable for use in myocardium scintigraphy. Its properties are suited to the use of a scintillation camera, which considerably shortens the examination time and thus allows an isotopic exploration of the myocardium from several incidences. The only disadvantage of this cyclotron-produced isotope seems to be its high price which will probably limit its use on a large scale. Fifty thallium 201 myocardium scintigraphs were practised on forty-eight coronary thrombosis patients. From this was established a precise topographic correlation between the electrocardiographic diagnosis and the scintigraph. The two corresponded in 47 cases out of 50. The few disagreements between ECG and scintigraphic results seem to be due either to poor-quality images or to an overall myocardium hypofixation connected with a very extensive necrosis. This means that thallium 201 myocardium scintigraphy is a reliable method of examination in the great majority of cases, giving a direct picture of the heart muscle and its necrotic lesions [fr

  18. Pre- and post-synaptic sympathetic function in human hibernating myocardium

    International Nuclear Information System (INIS)

    John, Anna S.; Pepper, John R.; Dreyfus, Gilles D.; Pennell, Dudley J.; Mongillo, Marco; Khan, Muhammad T.; Depre, Christophe; Rimoldi, Ornella E.; Camici, Paolo G.

    2007-01-01

    Impaired pre-synaptic noradrenaline uptake-1 mechanism has been reported in a swine model of hibernating myocardium (HM). To ascertain whether adrenergic neuroeffector abnormalities are present in human HM, we combined functional measurements in vivo using cardiovascular magnetic resonance (CMR) and positron emission tomography (PET) to assess pre- and post-synaptic sympathetic function. Twelve patients with coronary artery disease and chronic left ventricular (LV) dysfunction underwent CMR at baseline and 6 months after bypass for assessment of regional and global LV function and identification of segments with reversible dysfunction. Before surgery, myocardial noradrenaline uptake-1 ([ 11 C]meta-hydroxy-ephedrine; HED) and β-adrenoceptor (β-AR) density ([ 11 C]CGP-12177) were measured with PET. Patient PET data were compared with those in 18 healthy controls. The volume of distribution (V d ) of HED in HM (47.95±28.05 ml/g) and infarcted myocardium (42.69±25.76 ml/g) was significantly reduced compared with controls (66.09±14.48 ml/g). The V d of HED in normal myocardium (49.93±20.48 ml/g) of patients was also lower than that in controls and the difference was close to statistical significance (p=0.06). Myocardial β-AR density was significantly lower in HM (5.49±2.35 pmol/g), infarcted (4.82±2.61 pmol/g) and normal (5.86±1.81 pmol/g) segments of patients compared with healthy controls (8.61±1.32 pmol/g). Noradrenaline uptake-1 mechanism and β-AR density are reduced in the myocardium of patients with chronic LV dysfunction and evidence of HM. The increased sympathetic activity to the heart in these patients is a generalised rather than regional phenomenon which is likely to contribute to the remodelling process of the whole LV rather than playing a causative role in HM. (orig.)

  19. Ultrastructural alterations of atrial myocardium induced by adriamycin in chronically treated animals.

    Science.gov (United States)

    Lambertenghi-Deliliers, G; Zanon, P L; Pozzoli, E F; Bellini, O; Praga, C

    1978-02-28

    The clinical use of adriamycin (AM) is limited by a possible dose-dependent myocardiopathy. Severe lesions of ventricular myocardium widely described by electron microscopy have been correlated to irreversible congestive heart failure. On the other hand, the atrial contractile elements which differ from the ventricular ones because of the presence of the so-called specific granules have rarely been considered. In the work described in this paper, adriamycin was injected into rabbits and mice according to schedules of chronic toxicity. At the end of the treatment the atrial myocells presented diffuse ultrastructural lesions of mitochondria, sarcoplasmic reticulum and myofibrillar bundles. These alterations might be caused by the ribonucleoprotein synthesis inhibition, by a direct drug toxicity or by an energetic crisis due to early mitochondrial lesions. Besides, adriamycin produces a decrease of the specific atrial granules that play a hypothetic role in the metabolism of myocardial cells. However, lack of information about the contents and the exact function of atrial granules does not allow us to conclude that their decrease in treated animals has a pathogenetic significance in myocardiopathy induced by adriamycin.

  20. Fatty acid uptake in normal human myocardium

    International Nuclear Information System (INIS)

    Vyska, K.; Meyer, W.; Stremmel, W.; Notohamiprodjo, G.; Minami, K.; Machulla, H.J.; Gleichmann, U.; Meyer, H.; Koerfer, R.

    1991-01-01

    Fatty acid binding protein has been found in rat aortic endothelial cell membrane. It has been identified to be a 40-kDa protein that corresponds to a 40-kDa fatty acid binding protein with high affinity for a variety of long chain fatty acids isolated from rat heart myocytes. It is proposed that this endothelial membrane fatty acid binding protein might mediate the myocardial uptake of fatty acids. For evaluation of this hypothesis in vivo, influx kinetics of tracer-labeled fatty acids was examined in 15 normal subjects by scintigraphic techniques. Variation of the plasma fatty acid concentration and plasma perfusion rate has been achieved by modulation of nutrition state and exercise conditions. The clinical results suggest that the myocardial fatty acid influx rate is saturable by increasing fatty acid plasma concentration as well as by increasing plasma flow. For analysis of these data, functional relations describing fatty acid transport from plasma into myocardial tissue in the presence and absence of an unstirred layer were developed. The fitting of these relations to experimental data indicate that the free fatty acid influx into myocardial tissue reveals the criteria of a reaction on a capillary surface in the vicinity of flowing plasma but not of a reaction in extravascular space or in an unstirred layer and that the fatty acid influx into normal myocardium is a saturable process that is characterized by the quantity corresponding to the Michaelis-Menten constant, Km, and the maximal velocity, Vmax, 0.24 ± 0.024 mumol/g and 0.37 ± 0.013 mumol/g(g.min), respectively. These data are compatible with a nondiffusional uptake process mediated by the initial interaction of fatty acids with the 40-kDa membrane fatty acid binding protein of cardiac endothelial cells

  1. Non-gated computed tomography of left ventricular hypertrophy

    International Nuclear Information System (INIS)

    Harada, Junta

    1983-01-01

    Non-ECG gated computed tomography (CT) of the heart was carried out in 19 cases with cardiovascular diseases; 4 with mitral stenosis, 3 with aortic valve disease, 2 with combined valve disease, 8 with hypertrophic cardiomyopathy and one myocardial infarction and one aortic aneurysm. All cardiac diseases were studied by echocardiography and 13 of them further investigated by intracadiac catheterization. The interventricular septum and the apical and posterolateral wall of the left ventricle were segmentally evaluated as to relative wall thickness of myocardium on CT. The wall thickness was directly measured on left ventricular cine angiograms in 13 cases. O-G vector calculated by CT was compatible with the palne of vectorcardiography in evaluating left ventricular hypertorphy. Conclusion were as follows: 1) The degree and site of myocardial hypertrophy were detected by CT with satisfaction. 2) The area of ventricular myocardium increased in aortic valve disease and hypertrophic cardiomyopathy. 3) The direction and magnitude of O-G vector calculated by CT were well correlated to the half area of QRS loop in horizontal plane of vectorcardiography. (author)

  2. Diagnostic value of perfusion 201Tl scintigraphy of the myocardium in assessing right ventricular hypertrophy

    International Nuclear Information System (INIS)

    Jandova, R.; Bakos, K.; Fridl, P.

    1986-01-01

    Perfusion scintigraphy of the heart muscle with Tl 201 was tested in the diagnosis of overloading of the right ventricle in a group of 24 patients with chronic pulmonary disease and in a group of 26 patients with mitral stenosis only. The results of scintigraphy of the heart muscle and ECG examination were compared with results of the examination of haemodynamics of the lesser circulation, blood gases and spirometric examination. The study shows that thallium scintigraphy is a fairly sensitive method for noninvasive diagnosis of pulmonary arterial hypertension. It is an auxiliary method and its validity increases when combined with other noninvasive methods. (author)

  3. OSTEOPONTIN, INTERLEUKIN-15 AND DYSFUNCTION OF LEFT VENTRICULAR MYOCARDIUM IN HYPERTENSIVE PATIENTS WITH CHRONIC HEART FAILURE

    Directory of Open Access Journals (Sweden)

    O. M. Kovalyova

    2016-12-01

    Full Text Available Based on a survey of 108 patients with hypertension complicated by chronic heart failure, studied the connection concentration of osteopontin, interleukin-15 inserum and morpho-functional characteristics of the left ventricle of the heart. In patients with CHF osteopontin levels were significantly higher, it revealed a relationship between adverse LV filling state and knots in serum osteopontin, while the level of IL-15 did not show such a relationship. The results indicate the potential value of osteopontin as a biomarker for the diagnosis of CHF.

  4. Left ventricular remodelling in chronic primary mitral regurgitation: implications for medical therapy.

    Science.gov (United States)

    McCutcheon, Keir; Manga, Pravin

    Surgical repair or replacement of the mitral valve is currently the only recommended therapy for severe primary mitral regurgitation. The chronic elevation of wall stress caused by the resulting volume overload leads to structural remodelling of the muscular, vascular and extracellular matrix components of the myocardium. These changes are initially compensatory but in the long term have detrimental effects, which ultimately result in heart failure. Understanding the changes that occur in the myocardium due to volume overload at the molecular and cellular level may lead to medical interventions, which potentially could delay or prevent the adverse left ventricular remodelling associated with primary mitral regurgitation. The pathophysiological changes involved in left ventricular remodelling in response to chronic primary mitral regurgitation and the evidence for potential medical therapy, in particular beta-adrenergic blockers, are the focus of this review.

  5. Myocardium repair with stem cell therapy

    International Nuclear Information System (INIS)

    Peix, Amalia; Hidalgo, Jose; Dorticos, Elvira; Llerena, Lorenzo; Paredes, Angel; Torres, Maritza; Macias, Consuelo; Del Valle, Lazaro; Cabrera, Lazaro O; Carrillo, Regla; Mena, Eric; Fernandez, Yoel

    2006-01-01

    With the aim of assessing the efficacy of bone marrow-derived stem cells transplantation in patients with myocardial infarction and severe chronic heart failure through nuclear cardiology techniques, 15 revascularized patients were studied: nine (Group I) received autologous bone marrow-derived stem cells. The other six were controls (Group II). All underwent a clinical evaluation, radionuclide ventriculography, and gated-SPECT myocardial perfusion scintigraphy (MIBI-technetium99m, two-day protocol: dipyridamole - rest), before and three months after the procedure. At three months there was a clinical improvement in 89% of patients from Group I. The left ventricular ejection fraction increased: from 32±9% to 44±13% (p=0.03; Group I) and from 38±2% to 48±14% (p NS; Group II). The peak filling rate improved from 120±11 to 196±45 EDV/sec (p=0.03; Group I). The dipyridamole summed score diminished significantly only in Group I (from 35±5 to 23±14; p=0.02). The perfusion improvement was related to the implantation site in 60% of cases. We conclude that the bone marrow-derived stem cells transplantation is effective in patients with severe chronic heart failure of ischemic origin (au)

  6. Enhanced Electrical Integration of Engineered Human Myocardium via Intramyocardial versus Epicardial Delivery in Infarcted Rat Hearts.

    Directory of Open Access Journals (Sweden)

    Kaytlyn A Gerbin

    Full Text Available Cardiac tissue engineering is a promising approach to provide large-scale tissues for transplantation to regenerate the heart after ischemic injury, however, integration with the host myocardium will be required to achieve electromechanical benefits. To test the ability of engineered heart tissues to electrically integrate with the host, 10 million human embryonic stem cell (hESC-derived cardiomyocytes were used to form either scaffold-free tissue patches implanted on the epicardium or micro-tissue particles (~1000 cells/particle delivered by intramyocardial injection into the left ventricular wall of the ischemia/reperfusion injured athymic rat heart. Results were compared to intramyocardial injection of 10 million dispersed hESC-cardiomyocytes. Graft size was not significantly different between treatment groups and correlated inversely with infarct size. After implantation on the epicardial surface, hESC-cardiac tissue patches were electromechanically active, but they beat slowly and were not electrically coupled to the host at 4 weeks based on ex vivo fluorescent imaging of their graft-autonomous GCaMP3 calcium reporter. Histologically, scar tissue physically separated the patch graft and host myocardium. In contrast, following intramyocardial injection of micro-tissue particles and suspended cardiomyocytes, 100% of the grafts detected by fluorescent GCaMP3 imaging were electrically coupled to the host heart at spontaneous rate and could follow host pacing up to a maximum of 300-390 beats per minute (5-6.5 Hz. Gap junctions between intramyocardial graft and host tissue were identified histologically. The extensive coupling and rapid response rate of the human myocardial grafts after intramyocardial delivery suggest electrophysiological adaptation of hESC-derived cardiomyocytes to the rat heart's pacemaking activity. These data support the use of the rat model for studying electromechanical integration of human cardiomyocytes, and they

  7. Characterization of the Structural and Functional Changes in the Myocardium Following Focal Ischemia-Reperfusion Injury

    Science.gov (United States)

    Ojha, Navdeep; Roy, Sashwati; Radtke, Jared; Simonetti, Orlando; Gnyawali, Surya; Zweier, Jay L.; Kuppusamy, Periannan; Sen, Chandan K.

    2015-01-01

    High resolution (11.7T) cardiac magnetic resonance imaging (MRI) and histological approaches have been employed in tandem to characterize the secondary damage suffered by the murine myocardium following the initial insult caused by ischemia-reperfusion (IR). IR induced changes in the myocardium were examined in five separate groups at the following time-points after IR: 1h, 1d, 3d, 7d and 14 d. Infarct volume increased from 1h to 1d post-IR. Over time, loss of myocardial function was observed to be associated with increased infarct volume and worsened regional wall motion. In the infarct region, IR caused a decrease in end-systolic thickness coupled with small changes in end-diastolic thickness, leading to massive wall thickening abnormalities. In addition, compromised wall thickening was also observed in left ventricular regions adjacent to the infarct region. A tight correlation (r2 = 0.86) between measured MRI and triphenyltetrazolium chloride (TTC) infarct volumes was noted. Our observation that until day 3 post-IR, the infarct size as measured by TTC staining and MRI were much larger than the myocyte-silent regions in trichrome or H&E stained sections is consistent with the literature and leads to the conclusion that at such early phase the infarct site contains structurally intact myocytes that are functionally compromised. Over time, such affected myocytes were noted to structurally disappear resulting in consistent infarct sizes obtained from MRI, TTC as well as trichrome and hematoxylin/eosin analyses on day 7 following IR. Myocardial remodeling following IR includes secondary myocyte death followed by loss of cardiac function over time. PMID:18375718

  8. Stereoselective handling of perhexiline: implications regarding accumulation within the human myocardium.

    Science.gov (United States)

    Chong, Cher-Rin; Drury, Nigel E; Licari, Giovanni; Frenneaux, Michael P; Horowitz, John D; Pagano, Domenico; Sallustio, Benedetta C

    2015-12-01

    Perhexiline is a prophylactic anti-ischaemic agent with weak calcium antagonist effect which has been increasingly utilised in the management of refractory angina. The metabolic clearance of perhexiline is modulated by CYP2D6 metaboliser status and stereoselectivity. The current study sought to (1) determine whether the acute accumulation of perhexiline in the myocardium is stereoselective and (2) investigate the relationship between duration of short-term therapy and the potential stereoselective effects of perhexiline within myocardium. Patients (n = 129) from the active arm of a randomised controlled trial of preoperative perhexiline in cardiac surgery were treated with oral perhexiline for a median of 9 days. Correlates of atrial and ventricular concentrations of enantiomers were sought via univariate followed by multivariate analyses. Myocardial uptake of both (+) and (-) perhexiline was greater in ventricles than in atria, and there was more rapid clearance of (-) than (+) perhexiline. The main determinants of atrial uptake of both (+) and (-) perhexiline were the plasma concentrations [(+) perhexiline: β = -0.256, p = 0.015; (-) perhexiline: β = -0.347, p = 0.001] and patients' age [(+) perhexiline: β = 0.300, p = 0.004; (-) perhexiline: β = 0.288, p = 0.005]. Atrial uptake of (+) enantiomer also varied directly with duration of therapy (β = 0.228, p = 0.025), while atrial uptake of (-) perhexiline varied inversely with simultaneous heart rate (β = -0.240, p = 0.015). (1) Uptake of both perhexiline enantiomers into atrium is greater with advanced age and displays evidence of both saturability and minor stereoselectivity. (2) Atrial uptake of (-) perhexiline may selectively modulate heart rate reduction.

  9. Pyrophosphate scan of the temporarily ischemized dog myocardium

    Energy Technology Data Exchange (ETDEWEB)

    Duska, F.; Novak, J.; Vizda, J.; Kubicek, J.; Kafka, P.; Veverkova, O.

    1981-12-01

    In 9 dogs a transient myocardial ischemia was provoked using complete occlusion of the ramus interventricularis anterior of the left coronary artery. The occlusion was removed after 5, 10 or 15 min. Four hrs after removal of the occlusion a scan of the myocardium was carried out using sup(99m)Tc-labelled pyrophosphate. In 7 out of 9 dogs under study the scan was markedly positive, in 2 dogs negative. ECG demonstrated ischemic changes practically in all dogs; the changes became normal after removal of the occlusion, namely in 5 to 35 min. The histological examination of the tissue demonstrated in all 9 dogs only a slight impairment of the myocardium.

  10. Semi-automatic segmentation of myocardium at risk in T2-weighted cardiovascular magnetic resonance

    Directory of Open Access Journals (Sweden)

    Sjögren Jane

    2012-01-01

    Full Text Available Abstract Background T2-weighted cardiovascular magnetic resonance (CMR has been shown to be a promising technique for determination of ischemic myocardium, referred to as myocardium at risk (MaR, after an acute coronary event. Quantification of MaR in T2-weighted CMR has been proposed to be performed by manual delineation or the threshold methods of two standard deviations from remote (2SD, full width half maximum intensity (FWHM or Otsu. However, manual delineation is subjective and threshold methods have inherent limitations related to threshold definition and lack of a priori information about cardiac anatomy and physiology. Therefore, the aim of this study was to develop an automatic segmentation algorithm for quantification of MaR using anatomical a priori information. Methods Forty-seven patients with first-time acute ST-elevation myocardial infarction underwent T2-weighted CMR within 1 week after admission. Endocardial and epicardial borders of the left ventricle, as well as the hyper enhanced MaR regions were manually delineated by experienced observers and used as reference method. A new automatic segmentation algorithm, called Segment MaR, defines the MaR region as the continuous region most probable of being MaR, by estimating the intensities of normal myocardium and MaR with an expectation maximization algorithm and restricting the MaR region by an a priori model of the maximal extent for the user defined culprit artery. The segmentation by Segment MaR was compared against inter observer variability of manual delineation and the threshold methods of 2SD, FWHM and Otsu. Results MaR was 32.9 ± 10.9% of left ventricular mass (LVM when assessed by the reference observer and 31.0 ± 8.8% of LVM assessed by Segment MaR. The bias and correlation was, -1.9 ± 6.4% of LVM, R = 0.81 (p Conclusions There is a good agreement between automatic Segment MaR and manually assessed MaR in T2-weighted CMR. Thus, the proposed algorithm seems to be a

  11. Semi-automatic segmentation of myocardium at risk in T2-weighted cardiovascular magnetic resonance.

    Science.gov (United States)

    Sjögren, Jane; Ubachs, Joey F A; Engblom, Henrik; Carlsson, Marcus; Arheden, Håkan; Heiberg, Einar

    2012-01-31

    T2-weighted cardiovascular magnetic resonance (CMR) has been shown to be a promising technique for determination of ischemic myocardium, referred to as myocardium at risk (MaR), after an acute coronary event. Quantification of MaR in T2-weighted CMR has been proposed to be performed by manual delineation or the threshold methods of two standard deviations from remote (2SD), full width half maximum intensity (FWHM) or Otsu. However, manual delineation is subjective and threshold methods have inherent limitations related to threshold definition and lack of a priori information about cardiac anatomy and physiology. Therefore, the aim of this study was to develop an automatic segmentation algorithm for quantification of MaR using anatomical a priori information. Forty-seven patients with first-time acute ST-elevation myocardial infarction underwent T2-weighted CMR within 1 week after admission. Endocardial and epicardial borders of the left ventricle, as well as the hyper enhanced MaR regions were manually delineated by experienced observers and used as reference method. A new automatic segmentation algorithm, called Segment MaR, defines the MaR region as the continuous region most probable of being MaR, by estimating the intensities of normal myocardium and MaR with an expectation maximization algorithm and restricting the MaR region by an a priori model of the maximal extent for the user defined culprit artery. The segmentation by Segment MaR was compared against inter observer variability of manual delineation and the threshold methods of 2SD, FWHM and Otsu. MaR was 32.9 ± 10.9% of left ventricular mass (LVM) when assessed by the reference observer and 31.0 ± 8.8% of LVM assessed by Segment MaR. The bias and correlation was, -1.9 ± 6.4% of LVM, R = 0.81 (p Segment MaR, -2.3 ± 4.9%, R = 0.91 (p Segment MaR and manually assessed MaR in T2-weighted CMR. Thus, the proposed algorithm seems to be a promising, objective method for standardized MaR quantification in T2

  12. Role of action potential configuration and the contribution of C²⁺a and K⁺ currents to isoprenaline-induced changes in canine ventricular cells.

    Science.gov (United States)

    Szentandrássy, N; Farkas, V; Bárándi, L; Hegyi, B; Ruzsnavszky, F; Horváth, B; Bányász, T; Magyar, J; Márton, I; Nánási, P P

    2012-10-01

    Although isoprenaline (ISO) is known to activate several ion currents in mammalian myocardium, little is known about the role of action potential morphology in the ISO-induced changes in ion currents. Therefore, the effects of ISO on action potential configuration, L-type Ca²⁺ current (I(Ca)), slow delayed rectifier K⁺ current (I(Ks)) and fast delayed rectifier K⁺ current (I(Kr)) were studied and compared in a frequency-dependent manner using canine isolated ventricular myocytes from various transmural locations. Action potentials were recorded with conventional sharp microelectrodes; ion currents were measured using conventional and action potential voltage clamp techniques. In myocytes displaying a spike-and-dome action potential configuration (epicardial and midmyocardial cells), ISO caused reversible shortening of action potentials accompanied by elevation of the plateau. ISO-induced action potential shortening was absent in endocardial cells and in myocytes pretreated with 4-aminopyridine. Application of the I(Kr) blocker E-4031 failed to modify the ISO effect, while action potentials were lengthened by ISO in the presence of the I(Ks) blocker HMR-1556. Both action potential shortening and elevation of the plateau were prevented by pretreatment with the I(Ca) blocker nisoldipine. Action potential voltage clamp experiments revealed a prominent slowly inactivating I(Ca) followed by a rise in I(Ks) , both currents increased with increasing the cycle length. The effect of ISO in canine ventricular cells depends critically on action potential configuration, and the ISO-induced activation of I(Ks) - but not I(Kr) - may be responsible for the observed shortening of action potentials. © 2012 The Authors. British Journal of Pharmacology © 2012 The British Pharmacological Society.

  13. Role of action potential configuration and the contribution of Ca2+ and K+ currents to isoprenaline-induced changes in canine ventricular cells

    Science.gov (United States)

    Szentandrássy, N; Farkas, V; Bárándi, L; Hegyi, B; Ruzsnavszky, F; Horváth, B; Bányász, T; Magyar, J; Márton, I; Nánási, PP

    2012-01-01

    BACKGROUND AND PURPOSE Although isoprenaline (ISO) is known to activate several ion currents in mammalian myocardium, little is known about the role of action potential morphology in the ISO-induced changes in ion currents. Therefore, the effects of ISO on action potential configuration, L-type Ca2+ current (ICa), slow delayed rectifier K+ current (IKs) and fast delayed rectifier K+ current (IKr) were studied and compared in a frequency-dependent manner using canine isolated ventricular myocytes from various transmural locations. EXPERIMENTAL APPROACH Action potentials were recorded with conventional sharp microelectrodes; ion currents were measured using conventional and action potential voltage clamp techniques. KEY RESULTS In myocytes displaying a spike-and-dome action potential configuration (epicardial and midmyocardial cells), ISO caused reversible shortening of action potentials accompanied by elevation of the plateau. ISO-induced action potential shortening was absent in endocardial cells and in myocytes pretreated with 4-aminopyridine. Application of the IKr blocker E-4031 failed to modify the ISO effect, while action potentials were lengthened by ISO in the presence of the IKs blocker HMR-1556. Both action potential shortening and elevation of the plateau were prevented by pretreatment with the ICa blocker nisoldipine. Action potential voltage clamp experiments revealed a prominent slowly inactivating ICa followed by a rise in IKs, both currents increased with increasing the cycle length. CONCLUSIONS AND IMPLICATIONS The effect of ISO in canine ventricular cells depends critically on action potential configuration, and the ISO-induced activation of IKs– but not IKr– may be responsible for the observed shortening of action potentials. PMID:22563726

  14. Histology and Immunohistochemistry of the Cardiac Ventricular Structure in the Green Turtle (Chelonia mydas).

    Science.gov (United States)

    Braz, J K F S; Freitas, M L; Magalhães, M S; Oliveira, M F; Costa, M S M O; Resende, N S; Clebis, N K; Silva, N B; Moura, C E B

    2016-08-01

    This study describes the implications of cardiac ventricular microscopy in Chelonia mydas relating to its ability to dive. For this work, 11 specimens of the marine turtle species C. mydas found dead on the coast of Rio Grande do Norte (Northeast Brazil) were used. After necropsy, fragments of the cardiac ventricular wall were fixed in 10% buffered formaldehyde solution for 24 h and then subjected to routine processing for light and scanning electron microscopy (SEM). The ventricle in this species is formed by the epicardium, myocardium and endocardium. The subepicardial layer consists of highly vascularised connective tissue that emits septa to reinforce the myocardium surface. There is an abundant and diffuse subepicardial nerve plexus shown by immunostaining technique. The thickness of the spongy myocardium and the nature of its trabeculae varied between the heart chambers. The endocardium shows no characteristic elements of the heart conduction system. The valves have a hyaline cartilage skeleton, coated by dense irregular connective tissues characterised by elastic fibres. These findings in the green turtle ventricular microscopy are related to hypoxia resistance during diving. © 2015 Blackwell Verlag GmbH.

  15. Applications of magnetic resonance imaging in the assessment of left ventricular dysfunction

    Energy Technology Data Exchange (ETDEWEB)

    Beacock, David John

    2002-07-01

    This thesis has described the use of Magnetic Resonance Imaging (MRI) in the investigation of left ventricular dimensions and systolic function. This has been performed in conditions of left ventricular dysfunction, in congestive cardiac failure and following anterior myocardial infarction. The reproducibility of measurements of left ventricular dimensions using MRI has been presented. Such measurements were shown to be reproducible between different MRI studies of normal volunteers and patients with congestive heart failure. Furthermore, measurements from different MRI studies obtained from two commercially different systems were reproducible for the same subject groups. Ventricular dimensions and systolic function was evaluated in adult normal volunteers of different ages. Although left ventricular volumes and mass remained unchanged, detailed studies of the systolic images revealed significant differences between the two age groups. Differences in left ventricular cavity volumes and mass between patients with congestive heart failure and age-matched normal volunteers were also investigated. Left ventricular volumes and myocardial mass were assessed in a group of patients following anterior myocardial infarction. End-systolic volume was significantly increased compared to age-matched volunteers, but no changes in end-diastolic volume or myocardial mass was observed. Serial re-evaluation of these patients revealed no other changes over the subsequent six months. All these patients were treated with optimal medical therapy (thrombolysis, aspirin, beta-blockade and angiotensin converting enzyme inhibition). Thus, the use of this therapy may attenuate the process of left ventricular remodelling. Regional wall thickness was measured in the post-infarct patients. Wall thickening was significantly reduced both in the infarcted regions and in myocardium remote to the infarction. In contrast to previous echocardiographic studies, no 'hypercontractility' was

  16. Genetic bases of arrhythmogenic right ventricular cardiomyopathy

    Directory of Open Access Journals (Sweden)

    Alessandra Rampazzo

    2010-05-01

    Full Text Available Arrhythmogenic right ventricular cardiomyopathy (ARVC is a heart muscle disease in which the pathological substrate is a fibro-fatty replacement of the right ventricular myocardium. The major clinical features are different types of arrhythmias with a left branch block pattern. ARVC shows autosomal dominant inheritance with incomplete penetrance. Recessive forms were also described, although in association with skin disorders. Ten genetic loci have been discovered so far and mutations were reported in five different genes. ARVD1 was associated with regulatory mutations of transforming growth factor beta-3 (TGFβ3, whereas ARVD2, characterized by effort-induced polymorphic arrhythmias, was associated with mutations in cardiac ryanodine receptor-2 (RYR2. All other mutations identified to date have been detected in genes encoding desmosomal proteins: plakoglobin (JUP which causes Naxos disease (a recessive form of ARVC associated with palmoplantar keratosis and woolly hair; desmoplakin (DSP which causes the autosomal dominant ARVD8 and plakophilin-2 (PKP2 involved in ARVD9. Desmosomes are important cell-to-cell adhesion junctions predominantly found in epidermis and heart; they are believed to couple cytoskeletal elements to plasma membrane in cell-to-cell or cell-to-substrate adhesions.

  17. Arachidonic acid metabolism in fibroblasts derived from canine myocardium

    International Nuclear Information System (INIS)

    Weber, D.R.; Prescott, S.M.

    1986-01-01

    Canine fibroblasts from normal or healing infarcted myocardium were grown in culture. The cells were morphologically indistinguishable, but the doubling time of cells from healing myocardium was 39.6 +/- 3.5 hr whereas that of normals was 24 +/- 3.7 (n=5, p 3 H]arachidonate (AA) into phospholipids. Calcium ionophore A23187 (10 μM) caused release and metabolism of [ 3 H] AA. A23187 or AA (10μM) induced production of 6-keto PGF1α, PGE2, and a hydroxy metabolite of AA. RIA of 6-keto PGF1α showed that subconfluent cells from healing myocardium produced 1202 +/- 354 pg/mg protein whereas that of normals was 551 +/- 222 (n=7, p 3 H]AA released but did not metabolize [ 3 H]AA. In coincubations, fibroblasts incorporated myocyte-derived AA. Subsequent stimulation of the fibroblasts with A23187 induced the synthesis of 6-keto PGF1α, PGE2 and a hydroxy metabolite. The fibroblast content of healing myocardium was 35-1000 times that of normal tissue (n=7). Thus even a moderate change in AA metabolism, amplified by the AA released from deteriorating myocytes, may be a significant physiologic or pathologic event

  18. Multimodality imaging demonstrates trafficking of liposomes preferentially to ischemic myocardium

    International Nuclear Information System (INIS)

    Lipinski, Michael J.; Albelda, M. Teresa; Frias, Juan C.; Anderson, Stasia A.; Luger, Dror; Westman, Peter C.; Escarcega, Ricardo O.; Hellinga, David G.; Waksman, Ron; Arai, Andrew E.; Epstein, Stephen E.

    2016-01-01

    Introduction: Nanoparticles may serve as a promising means to deliver novel therapeutics to the myocardium following myocardial infarction. We sought to determine whether lipid-based liposomal nanoparticles can be shown through different imaging modalities to specifically target injured myocardium following intravenous injection in an ischemia–reperfusion murine myocardial infarction model. Methods: Mice underwent ischemia–reperfusion surgery and then either received tail-vein injection with gadolinium- and fluorescent-labeled liposomes or no injection (control). The hearts were harvested 24 h later and underwent T1 and T2-weighted ex vivo imaging using a 7 Tesla Bruker magnet. The hearts were then sectioned for immunohistochemistry and optical fluorescent imaging. Results: The mean size of the liposomes was 100 nm. T1-weighted signal intensity was significantly increased in the ischemic vs. the non-ischemic myocardium for mice that received liposomes compared with control. Optical imaging demonstrated significant fluorescence within the infarct area for the liposome group compared with control (163 ± 31% vs. 13 ± 14%, p = 0.001) and fluorescent microscopy confirmed the presence of liposomes within the ischemic myocardium. Conclusions: Liposomes traffic to the heart and preferentially home to regions of myocardial injury, enabling improved diagnosis of myocardial injury and could serve as a vehicle for drug delivery.

  19. Multimodality imaging demonstrates trafficking of liposomes preferentially to ischemic myocardium

    Energy Technology Data Exchange (ETDEWEB)

    Lipinski, Michael J., E-mail: mjlipinski12@gmail.com [MedStar Heart and Vascular Institute, MedStar Washington Hospital Center, Washington, DC (United States); Albelda, M. Teresa [GIBI2" 3" 0, Grupo de Investigación Biomédica en Imagen, IIS La Fe, Valencia (Spain); Frias, Juan C. [Departamento de Ciencias Biomédicas, Universidad CEU Cardenal Herrera, Valencia (Spain); Anderson, Stasia A. [Advanced Cardiovascular Imaging Laboratory, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD (United States); Luger, Dror; Westman, Peter C.; Escarcega, Ricardo O.; Hellinga, David G.; Waksman, Ron [MedStar Heart and Vascular Institute, MedStar Washington Hospital Center, Washington, DC (United States); Arai, Andrew E. [Advanced Cardiovascular Imaging Laboratory, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD (United States); Epstein, Stephen E. [MedStar Heart and Vascular Institute, MedStar Washington Hospital Center, Washington, DC (United States)

    2016-03-15

    Introduction: Nanoparticles may serve as a promising means to deliver novel therapeutics to the myocardium following myocardial infarction. We sought to determine whether lipid-based liposomal nanoparticles can be shown through different imaging modalities to specifically target injured myocardium following intravenous injection in an ischemia–reperfusion murine myocardial infarction model. Methods: Mice underwent ischemia–reperfusion surgery and then either received tail-vein injection with gadolinium- and fluorescent-labeled liposomes or no injection (control). The hearts were harvested 24 h later and underwent T1 and T2-weighted ex vivo imaging using a 7 Tesla Bruker magnet. The hearts were then sectioned for immunohistochemistry and optical fluorescent imaging. Results: The mean size of the liposomes was 100 nm. T1-weighted signal intensity was significantly increased in the ischemic vs. the non-ischemic myocardium for mice that received liposomes compared with control. Optical imaging demonstrated significant fluorescence within the infarct area for the liposome group compared with control (163 ± 31% vs. 13 ± 14%, p = 0.001) and fluorescent microscopy confirmed the presence of liposomes within the ischemic myocardium. Conclusions: Liposomes traffic to the heart and preferentially home to regions of myocardial injury, enabling improved diagnosis of myocardial injury and could serve as a vehicle for drug delivery.

  20. Mammalian cell biology

    International Nuclear Information System (INIS)

    Elkind, M.M.

    1979-01-01

    This section contains summaries of research on mechanisms of lethality and radioinduced changes in mammalian cell properties, new cell systems for the study of the biology of mutation and neoplastic transformation, and comparative properties of ionizing radiations

  1. Lone ventricular cardiomyopathy,

    African Journals Online (AJOL)

    ... (I) cardiac catheterisation, including coronary arteriography and pulmonary ... described existence of lone ventricular idiopathic ... spectrum of classic idiopathic dilated cardiomyopathy. ... endomyocardial fibrosis, and from discussions at an.

  2. A Prospective Study of Ripple Mapping the Post-Infarct Ventricular Scar to Guide Substrate Ablation for Ventricular Tachycardia.

    Science.gov (United States)

    Luther, Vishal; Linton, Nick W F; Jamil-Copley, Shahnaz; Koa-Wing, Michael; Lim, Phang Boon; Qureshi, Norman; Ng, Fu Siong; Hayat, Sajad; Whinnett, Zachary; Davies, D Wyn; Peters, Nicholas S; Kanagaratnam, Prapa

    2016-06-01

    Post-infarct ventricular tachycardia is associated with channels of surviving myocardium within scar characterized by fractionated and low-amplitude signals usually occurring late during sinus rhythm. Conventional automated algorithms for 3-dimensional electro-anatomic mapping cannot differentiate the delayed local signal of conduction within the scar from the initial far-field signal generated by surrounding healthy tissue. Ripple mapping displays every deflection of an electrogram, thereby providing fully informative activation sequences. We prospectively used CARTO-based ripple maps to identify conducting channels as a target for ablation. High-density bipolar left ventricular endocardial electrograms were collected using CARTO3v4 in sinus rhythm or ventricular pacing and reviewed for ripple mapping conducting channel identification. Fifteen consecutive patients (median age 68 years, left ventricular ejection fraction 30%) were studied (6 month preprocedural implantable cardioverter defibrillator therapies: median 19 ATP events [Q1-Q3=4-93] and 1 shock [Q1-Q3=0-3]). Scar (ripple mapping conducting channels were seen within each scar (length 60 mm; initial component 0.44 mV; delayed component 0.20 mV; conduction 55 cm/s). Ablation was performed along all identified ripple mapping conducting channels (median 18 lesions) and any presumed interconnected late-activating sites (median 6 lesions; Q1-Q3=2-12). The diastolic isthmus in ventricular tachycardia was mapped in 3 patients and colocated within the ripple mapping conducting channels identified. Ventricular tachycardia was noninducible in 85% of patients post ablation, and 71% remain free of ventricular tachycardia recurrence at 6-month median follow-up. Ripple mapping can be used to identify conduction channels within scar to guide functional substrate ablation. © 2016 American Heart Association, Inc.

  3. Blood flow, flow reserve, and glucose utilization in viable and nonviable myocardium in patients with ischemic cardiomyopathy.

    Science.gov (United States)

    Zhang, Xiaoli; Schindler, Thomas H; Prior, John O; Sayre, James; Dahlbom, Magnus; Huang, Sung-Cheng; Schelbert, Heinrich R

    2013-04-01

    The aim of the study was to determine whether glucose uptake in viable myocardium of ischemic cardiomyopathy patients depends on rest myocardial blood flow (MBF) and the residual myocardial flow reserve (MFR). Thirty-six patients with ischemic cardiomyopathy (left ventricular ejection fraction 25 ± 10 %) were studied with (13)N-ammonia and (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET). Twenty age-matched normals served as controls. Regional MBF was determined at rest and during dipyridamole hyperemia and regional FDG extraction was estimated from regional FDG to (13)N-ammonia activity ratios. Rest MBF was reduced in viable (0.42 ± 0.18 ml/min per g) and nonviable regions (0.32 ± 0.09 ml/min per g) relative to remote regions (0.68 ± 0.23 ml/min per g, p MFRs did not differ significantly (p > 0.05). Compared to MFR in remote myocardium, MFRs in viable regions were similar (1.39 ± 0.56 vs 1.70 ± 0.45, p > 0.05) but were significantly lower in nonviable regions (1.23 ± 0.43, p MFRs (r =-0.424, p MFRs in viable myocardium are associated with increasing glucose extraction that likely reflects a metabolic adaptation of remodeling hibernating myocytes.

  4. Cardiac magnetic resonance imaging for evaluation of non-compaction cardiomyopathy in patients with or without left ventricular systolic dysfunction

    International Nuclear Information System (INIS)

    Deviggiano, A.; Deschle, H.; Lewkowicz, J.M.; Tajer, C.D.; Carrascosa, P.; Capunay, C.; Vallejos, J.; Stewart Harris, A.

    2011-01-01

    Background: Non-compaction cardiomyopathy (NCC) is a genetic disorder characterized by deep trabeculations in the ventricular wall, which define recesses communicating with the main ventricular chamber. The prevalence of NCC is greater in symptomatic populations with left ventricular dysfunction; yet, it may also be detected in asymptomatic patients with normal left ventricular function using novel diagnostic tools. However, this condition is under-diagnosed due to a low index of clinical suspicion and to the use of echocardiography classifications based on different diagnostic criteria. The use of cardiac magnetic resonance imaging (CMRI) has established two diagnostic criteria that clearly recognize this disease. Objective: To evaluate the clinical and morphological characteristics of patients with NCC with and without systolic dysfunction undergoing cardiac magnetic resonance imaging (CMRI). Material and Methods: A total of 20 patients with NCC were retrospectively included. The following parameters were determined: left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV); left ventricular end-diastolic diameter (LVEDD); left ventricular end-systolic diameter (LVESD); cardiac mass and left ventricular trabeculations. The distribution of NC myocardium was evaluated according to the model of 17 myocardial segments. Results: Mean myocardial thickness was 13.1 ± 3.3 mm and 3.6 ± 0.6 mm in NC versus normal myocardium, respectively. Patients with left ventricular dysfunction presented increased LVEDD, LVEDV, total cardiac mass, and LV non-compaction and trabeculations. We found a positive correlation and a linear relationship between LVEDD and TLVM (g/m 2 ): r=0.76; r 2 =0.59; p [es

  5. Experimental Model of Gene Transfection in Healthy Canine Myocardium: Perspectives of Gene Therapy for Ischemic Heart Disease

    Directory of Open Access Journals (Sweden)

    Renato A. K. Kalil

    2002-09-01

    Full Text Available OBJECTIVE: To assess the transfection of the gene that encodes green fluorescent protein (GFP through direct intramyocardial injection. METHODS: The pREGFP plasmid vector was used. The EGFP gene was inserted downstream from the constitutive promoter of the Rous sarcoma virus. Five male dogs were used (mean weight 13.5 kg, in which 0.5 mL of saline solution (n=1 or 0.5 mL of plasmid solution containing 0.5 µg of pREGFP/dog (n=4 were injected into the myocardium of the left ventricular lateral wall. The dogs were euthanized 1 week later, and cardiac biopsies were obtained. RESULTS: Fluorescence microscopy showed differences between the cells transfected and not transfected with pREGFP plasmid. Mild fluorescence was observed in the cardiac fibers that received saline solution; however, the myocardial cells transfected with pREGFP had overt EGFP expression. CONCLUSION: Transfection with the EGFP gene in healthy canine myocardium was effective. The reproduction of this efficacy using vascular endothelial growth factor (VEGF instead of EGFP aims at developing gene therapy for ischemic heart disease.

  6. Effects of Using Tricaine Methanesulfonate and Metomidate before Euthanasia on the Contractile Properties of Rainbow Trout (Oncorhynchus mykiss) Myocardium.

    Science.gov (United States)

    Roberts, Jordan C; Syme, Douglas A

    2016-01-01

    Because many anesthetics work through depressing cell excitability, unanesthetized euthanasia has become common for research involving excitable tissues (for example muscle and nerve) to avoid these depressive effects. However, anesthetic use during euthanasia may be indicated for studies involving isolated tissues if the potential depressive effects of brief anesthetic exposure dissipate after subsequent tissue isolation, washout, and saline perfusion. We explore this here by measuring whether, when applied prior to euthanasia, standard immersion doses of 2 fish anesthetics, tricaine methanesulfonate (TMS; 100 mg/L, n = 6) and methyl 1-(1-phenylethyl)-1H-imidazole-5-carboxylate (metomidate, 10 mg/L, n = 6), have residual effects on the contractile properties (force and work output) of isolated and saline-perfused ventricular compact myocardium from rainbow trout (Oncorhynchus mykiss). Results suggest that direct exposure of muscle to immersion doses of TMS-but not metomidate-impairs muscle contractile performance. However, brief exposure (2 to 3 min) to either anesthetic during euthanasia only-providing that the agent is washed out prior to tissue experimentation-does not have an effect on the contractile properties of the myocardium. Therefore, the use of TMS, metomidate, and perhaps other anesthetics that depress cell excitability during euthanasia may be indicated when conducting research on isolated and rinsed tissues.

  7. Cardiac lymphoscintigraphy following closed-chest catheter injection of radiolabeled colloid into the myocardium of dogs: concise communication

    International Nuclear Information System (INIS)

    Osbakken, M.D.; Kopiwoda, S.Y.; Swan, A.; Castronovo, F.P.; Strauss, H.W.

    1982-01-01

    A catheter technique for injection of radiolabeled colloids into the myocardium was developed and tested in a series of 15 dogs. A multipurpose angiographic catheter was modified to permit an inner core of PE-50 polyethylene tubing, tipped with a 23-gage needle, to pass through the lumen for intra-myocardial injection of radiocolloids. For injection of the left ventricle, the catheter is introduced through the femoral artery: for the right ventricle, the femoral vein. The catheter advanced under fluoroscopy until the desired surface for injection is reached. The inner core is then extended to lodge the needle in the endocardium. A mixture of Renografin (to confirm the endocardial injection site) and radiolabeled colloid was injected in 13 animals. Ten minutes after injection, scintigraphy was begun and continued for up to 6 hr. In three dogs the procedure was repeated 3 or 4 times. From two to five nodes were visible in all animals, irrespective of whether the right or left ventricular myocardium was injected. In two animals the injection was given intravenously, and no nodes were seen. These data suggest that cardiac lymphatic drainage can be studied with a catheter injection method

  8. Cardiac lymphoscintigraphy following closed-chest catheter injection of radiolabeled colloid into the myocardium of dogs: concise communication

    International Nuclear Information System (INIS)

    Osbakken, M.D.; Kopiwoda, S.Y.; Swan, A.; Castronovo, F.P.; Strauss, H.W.

    1982-01-01

    A catheter technique for injection of radiolabeled colloids into the myocardium was developed and tested in a series of 15 dogs. A multipurpose angiographic catheter was modified to permit an inner core of PE-50 polyethylene tubing, tipped with a 23-gage needle, to pass through the lumen for intra-myocardial injection of the femoral artery: for the right ventricle, the femoral vein. The catheter advanced under fluoroscopy until the desired surface for injection is reached. The inner core is then extended to lodge the needle in the endocardium. A mixture of Renogratin (to confirm the endocardial injection site) and radiolabeled colloid was injected in up to 6 hr. In three dogs the procedure was repeated 3 or 4 times. From two to five nodes were visible in all animals, irrespective of whether the right or left ventricular myocardium was injected. In two animals the injection was given intravenously, and no nodes were seen. These data suggest that cardiac lymphatic drainage can be studied with a catheter injection method

  9. Incidence of stunned, hibernating and scarred myocardium in ischaemic cardiomyopathy

    International Nuclear Information System (INIS)

    Hernandez-Pampaloni, Miguel; Morita, Koichi; Dutka, David P.; Camici, Paolo G.; Bax, Jeroen J.

    2005-01-01

    Different criteria to identify residual viability in chronically dysfunctioning myocardium in patients with coronary artery disease (CAD) can be derived by the combined assessment of myocardial blood flow (MBF) and glucose utilisation (MRG) using positron emission tomography (PET). The aim of this study was to evaluate, in a large number of patients, the prevalence of these different patterns by purely quantitative means. One hundred and sixteen consecutive patients with ischaemic cardiomyopathy (LVEF ≤40%) underwent resting 2D echocardiography to assess regional contractile function (16-segment model). PET with 15 O-labelled water (H 2 15 O) and 18 F-fluorodeoxyglucose (FDG) was used to quantify MBF and MRG during hyperinsulinaemic euglycaemic clamp. Dysfunctional segments with normal MBF (≥0.6 ml min -1 g -1 ) were classified as stunned, and segments with reduced MBF ( -1 g -1 ) as hibernating if MRG was ≥0.25 μmol min -1 g -1 . Segments with reduced MBF and MRG -1 g -1 were classified as transmural scars and segments with reduced MBF and MRG between 0.20 and 0.25 μmol min -1 g -1 as non-transmural scars. Eight hundred and thirty-four (46%) segments were dysfunctional. Of these, 601 (72%) were chronically stunned, with 368 (61%) having normal MRG (0.47±0.20 μmol min -1 g -1 ) and 233 (39%) reduced MRG (0.16±0.05 μmol min -1 g -1 ). Seventy-four (9%) segments with reduced MBF had preserved MRG (0.40±0.18 μmol min -1 g -1 ) and were classified as hibernating myocardium. In addition, 15% of segments were classified as transmural and 4% as non-transmural scar. The mean MBF was highest in stunned myocardium (0.95±0.32 ml min -1 g -1 ), intermediate in hibernating myocardium and non-transmural scars (0.47±0.09 ml min -1 g -1 and 0.48±0.08 ml min -1 g -1 , respectively), and lowest in transmural scars (0.40±0.14 ml min -1 g -1 , P -1 g -1 vs 0.46±0.20 μmol min -1 g -1 , NS), and lowest in stunned myocardium with reduced MRG and transmural scars

  10. [Effect of adaptation to hypoxia on expression of NO synthase isoforms in rat myocardium].

    Science.gov (United States)

    Goryacheva, A V; Terekhina, O L; Abramochkin, D V; Budanova, O P; Belkina, L M; Smirin, B V; Downey, H F; Malyshev, I Yu; Manukhina, E B

    2015-01-01

    Previously we have shown that adaptation to hypoxia (AH) is cardio- and vasoprotective in myocardial ischemic and reperfusion injury and this protection is associated with restriction of nitrosative stress. The present study was focused on further elucidation of NO-dependent mechanisms of AH by identifying specific NO synthases (NOS) that could play the major role in AH protection. AH was performed in a normobaric hypoxic chamber by breathing hypoxic gas mixture (9.5-10% O2) for 5-10 min with intervening 4 min normoxia (5-8 cycles daily for 21 days). Expression of neuronal (nNOS), inducible (iNOS), and endothelial (eNOS) protein was measured in the left ventricular myocardium using Western blot analysis with respective antibodies. AH educed iNOS protein expression by 71% (p < 0.05) whereas eNOS protein expression tended to be reduced by 41% compared to control (p < 0.05). nNOS protein expression remained unchanged after AH. Selective iNOS inhibition can mimic the AH-induced protection. Therefore protective effects of AH could be at least partially due to restriction of iNOS and, probably, eNOS expression.

  11. Wearable Multi-Channel Microelectrode Membranes for Elucidating Electrophysiological Phenotypes of Injured Myocardium

    Science.gov (United States)

    Cao, Hung; Yu, Fei; Zhao, Yu; Zhang, Xiaoxiao; Tai, Joyce; Lee, Juhyun; Darehzereshki, Ali; Bersohn, Malcolm; Lien, Ching-Ling; Chi, Neil C.; Tai, Yu-Chong; Hsiai, Tzung K.

    2014-01-01

    Understanding the regenerative capacity of small vertebrate models has provided new insights into the plasticity of injured myocardium. Here, we demonstrated the application of flexible microelectrode arrays (MEAs) in elucidating electrophysiological phenotypes of zebrafish and neonatal mouse models of heart regeneration. The 4-electrode MEA membranes were designed to detect electrical signals in the aquatic environment. They were micro-fabricated to adhere to the non-planar body surface of zebrafish and neonatal mice. The acquired signals were processed to display electrocardiogram (ECG) with high signal-to-noise-ratios, and were validated via the use of conventional micro-needle electrodes. The 4-channel MEA provided signal stability and spatial resolution, revealing the site-specific electrical injury currents such as ST-depression in response to ventricular cryo-injury. Thus, our polymer-based and wearable MEA membranes provided electrophysiological insights in long-term conduction phenotypes for small vertebral models of heart injury and regeneration with a translational implication for monitoring cardiac patients. PMID:24945366

  12. Bone marrow and bone marrow derived mononuclear stem cells therapy for the chronically ischemic myocardium

    International Nuclear Information System (INIS)

    Waksman, Ron; Baffour, Richard

    2003-01-01

    Bone marrow stem cells have been shown to differentiate into various phenotypes including cardiomyocytes, vascular endothelial cells and smooth muscle. Bone marrow stem cells are mobilized and home in to areas of injured myocardium where they are involved in tissue repair. In addition, bone marrow secretes multiple growth factors, which are essential for angiogenesis and arteriogenesis. In some patients, these processes are not enough to avert clinical symptoms of ischemic disease. Therefore, in vivo administration of an adequate number of stem cells would be a significant therapeutic advance. Unfractionated bone marrow derived mononuclear stem cells, which contain both hematopoietic and nonhematopoietic cells may be more appropriate for cell therapy. Studies in animal models suggest that implantation of different types of stem cells improve angiogenesis and arteriogenesis, tissue perfusion as well as left ventricular function. Several unanswered questions remain. For example, the optimal delivery approach, dosage and timing of the administration of cell therapy as well as durability of improvements need to be studied. Early clinical studies have demonstrated safety and feasibility of various cell therapies in ischemic disease. Randomized, double blind and placebo-controlled clinical trials need to be completed to determine the effectiveness of stem cell

  13. [Structural and functional changes of myocardium in Chernobyl disaster clean-up workers with atrial fibrillation].

    Science.gov (United States)

    Khomaziuk, I M; Habulavichene, Zh M; Khomaziuk, V A

    2011-01-01

    Particularities and clinical importance of the structural and functional changes of myocardium were estimated in Chernobyl disaster clean-up workers with atrial fibrillation (AF). We examined 122 men with AF, which was associated with ischemic heart disease and arterial hypertension. Paroxysmal AF was diagnosed in 42 patients, 80 patients had permanent AE Control group comprised 80 men without AF. Echocardiography and Doppler studies were performed using ultrasound scanner Aloka SSD-630 (Japan). Significant structural and functional changes of the heart were revealed already in paroxysmal AF and became more pronounced in permanent AF. Increased left atrial size, its ratio to left ventricular end diastolic diameter, diastolic dysfunction were important echocardiographic predictors of AF. Heart walls thickening was accompanied by disorders of myocardial relaxation, increase in myocardial mass led to ischemia, and together they promoted overload, dysfunction of atrium and development of AF. Obligatory echocardiographic examination of the Chernobyl disaster clean-up workers with ischemic heart disease and arterial hypertension is necessary for predicting AF early, ordering adequate therapy in proper time and improving prognosis.

  14. Mammalian cell biology

    International Nuclear Information System (INIS)

    Elkind, M.M.

    1975-01-01

    Progress is reported on the following research projects: the effects of N-ethyl-maleimide and hydroxyurea on hamster cells in culture; sensitization of synchronized human cells to x rays by N-ethylmaleimide; sensitization of hypoxic mammalian cells with a sulfhydryl inhibitor; damage interaction due to ionizing and nonionizing radiation in mammalian cells; DNA damage relative to radioinduced cell killing; spurious photolability of DNA labeled with methyl- 14 C-thymidine; radioinduced malignant transformation of cultured mouse cells; a comparison of properties of uv and near uv light relative to cell function and DNA damage; Monte Carlo simulation of DNA damage and repair mechanisms; and radiobiology of fast neutrons

  15. 99mTcO(BAT-NI), a novel nitroimidazole tracer: in vivo uptake studies in ischaemic myocardium

    International Nuclear Information System (INIS)

    Hoffend, J.; Linke, G.; Mohammed, A.; Haberkorn, U.; Tiefenbacher, C.P.; Eisenhut, M.

    2003-01-01

    Myocardial perfusion single-photon emission tomography (SPET) performed with cationic technetium-99m complexes indicates ischaemic areas as cold lesions. By contrast, nitroimidazole derivatives labelled with fluorine-18 or 99m Tc have recently shown promising results for hot spot imaging of ischaemic myocardium. This study evaluates 99m TcO(BAT-NI), a new 99m Tc complex comprising the nitroimidazole ligand, 2,10-dimercapto-2, 10-dimethyl-4, 8-diaza-6-[4-(2-nitroimidazolyl)butyl]undecane, in a low-flow in vivo model of myocardial ischaemia in thoracotomised rats. To elucidate the influence of the 2-nitroimidazole group on ischaemia-induced uptake, comparisons with ligand derivatives were performed where (a) the 2-nitro group was deleted [ 99m TcO(BAT-I)], (b) the 2-nitroimidazole functionality was replaced by a Br atom [ 99m TcO(BAT-Br)] and (c) the 99m TcO(BAT) moiety was replaced by an iodine-125 iodophenoxybutyl ligand ( 125 IP-NI). The radiolabelled compounds were i.v. injected 15 min after reducing resting myocardial blood flow by 50-60% and the uptake of radioactivity was assessed 90 min post injection. Autoradiography of left ventricular short-axis slices showed median uptake ratios of ischaemic/non-ischaemic myocardium (I/N) of 3.4, 4.5 and 3.4 for 99m TcO(BAT-NI), 99m TcO(BAT-I) and 99m TcO(BAT-Br), respectively. In contrast, 125 IP-NI was not preferentially taken up by ischaemic myocardium. Accumulation of 99m TcO(BAT-NI) in ischaemic heart regions was comparable to that in the liver. Biodistribution studies showed a median uptake of 0.65% ID/g of 99m TcO(BAT-NI) in ischaemic tissue and an I/N of 3.3. On planar images of the thorax and upper abdomen the ischaemic hearts were visualised faintly; the median heart to lung count ratio for 99m TcO(BAT-NI) was 1.7, and the median heart to liver count ratio was 1.0. We conclude that uptake of 99m TcO(BAT-NI) in ischaemic myocardium does not depend on the nitroimidazole moiety but is intrinsic to the BAT complex

  16. [Effects of genistein on contractility of isolated right ventricular muscles in guinea pig].

    Science.gov (United States)

    Wu, Jin-xia; Li, Hong-fang; Liu, Chong-bin; Tian, Zhi-feng

    2008-11-01

    To study the effect of genistein (GEN) on contractility of isolated right ventricular muscles in guinea pig and its mechanisms. Isolated guinea pig ventricular muscles were suspended in organ baths containing K-H solution.After an equilibration period, the effect of GEN on contraction of myocardium was observed. GEN and isoprenaline hydrochloride had the positive inotropic effects on contractity of myocardium. Meanwhile, the effect of GEN (1-100 micromol x L(-1)) was in dose-dependent manner. Propranolol (1 micromol x L(-1)) and verapamil hydrochloride (0.5 micromol x L(-1)) attenuated the positive inotropic effect of isoprenaline hydrochloride (1 micromol x L(-1)), but did not change the effect of GEN (50 micromol x L(-1)). Further more, the enhancement of the contraction induced by elevation of extracellular Ca2+ concentration in ventricular muscles had no change after pretreatment with GEN (1.10 micromol x L(-1)). In addition,the positive inotropic effect of GEN was inhibited partially by tamoxifen (1 micromol x L(-1)) and SQ22536 (1 micromol x L(-1)), also, could be attenuated by bpV (1 micromol x L(-1)). GEN has the positive inotropic effect on guinea pig ventricular muscles, which is not related to the activation of beta adrenoceptor, Ca2+ channel on cell membrane,but may involve in cAMP of intracellular signal transduction and tyrosine kinase pathway.

  17. Reduction in beta-myosin heavy chains in stunned myocardium as assessed by nondenaturing gel electrophoresis.

    Science.gov (United States)

    Garcia, S C; Pomblum, V J; Gams, E; Rupp, H; Schipke, J D

    2007-09-01

    Myosin plays a key role in the structure and function of cardiac muscle. Three myosin isoenzymes (V(1), V(2), and V(3)) with different ATPase activities have been identified in mammalian ventricles based on their heavy chain constituents. The relative amount of myosin isoenzymes changes under physiological and pathological conditions. Until now, myosin isoenzymes have frequently been determined using either tube gel (nondenaturing) polyacrylamide gel electrophoresis (PAGE), or gradient or uniform sodium dodecyl sulfate (denaturing) PAGE. Both methods have disadvantages, e.g., a long running time. We developed, therefore, a uniform, nondenaturing PAGE with slab minigel format for analyzing the myosin isoenzymes in normoxic and stunned rabbit hearts. In normoxic hearts of adult rabbits, V(3) predominated over V(1) (46 vs 41%). In turn, in the stunned hearts, V(1) predominated over V(3) (70 vs 30%), and the heterodimeric V(2) was not anymore detectable. This alteration appears to result from a selective loss of myosin heavy chain (MHC)-beta. In parallel, the biochemical markers troponin I and creatine kinase were increased in the stunned hearts. We suggest that alterations of myosin isoenzymes in stunned myocardium can be monitored with native PAGE. The present analysis of myosin isoenzyme appears thus as a new tool for evaluating defects in MHC dimer formation in postischemic hearts.

  18. 99m Technetium pyrophosphate myocardium scintigraphy. First results

    International Nuclear Information System (INIS)

    Toussaint, Paul.

    1976-01-01

    99m technetium pyrophosphate myocardium scintigraphy is a very recent examination technique. This work gives the results obtained on 61 patients. As a vector of the isotope, pyrophosphate has the advantage over polyphosphate of a fast bone uptake there it should be stressed that a 90 minute pause is necessary between the intraveinous injection of the isotope and the photographic recording so that the reading is not troubled by the labelled intracardiac blood pool image, an image quality criterion being the estimation of a good costal fixation which in fact appears sooner or later according to the subject. The role of pyrophosphate, chelator of calcium in fixation of the isotope on the myocardium, could be explained by the fast appearance of 'dense bodies', made up of calcium hydroxyapathice crystals, in the mitochondria of myocardium cells having undergone an irreversible necrotic process. The choice of 99 m technetium is based on its ease of use: 6 hour half-life, high-energy pure gamma emission at 140 keV. The fixed image studied under two incidences, front and left anterior oblique, is obtained from mobile images given by the scintillation camera used in connection with a data processing system. Several facts are underlined, explaining the disadvantages, advantages and indications of the method [fr

  19. Building the mammalian testis

    DEFF Research Database (Denmark)

    Svingen, Terje; Koopman, Peter

    2013-01-01

    Development of testes in the mammalian embryo requires the formation and assembly of several cell types that allow these organs to achieve their roles in male reproduction and endocrine regulation. Testis development is unusual in that several cell types such as Sertoli, Leydig, and spermatogonial...

  20. Mammalian development in space

    Science.gov (United States)

    Ronca, April E.

    2003-01-01

    Life on Earth, and thus the reproductive and ontogenetic processes of all extant species and their ancestors, evolved under the constant influence of the Earth's l g gravitational field. These considerations raise important questions about the ability of mammals to reproduce and develop in space. In this chapter, I review the current state of our knowledge of spaceflight effects on developing mammals. Recent studies are revealing the first insights into how the space environment affects critical phases of mammalian reproduction and development, viz., those events surrounding fertilization, embryogenesis, pregnancy, birth, postnatal maturation and parental care. This review emphasizes fetal and early postnatal life, the developmental epochs for which the greatest amounts of mammalian spaceflight data have been amassed. The maternal-offspring system, the coordinated aggregate of mother and young comprising mammalian development, is of primary importance during these early, formative developmental phases. The existing research supports the view that biologically meaningful interactions between mothers and offspring are changed in the weightlessness of space. These changes may, in turn, cloud interpretations of spaceflight effects on developing offspring. Whereas studies of mid-pregnant rats in space have been extraordinarily successful, studies of young rat litters launched at 9 days of postnatal age or earlier, have been encumbered with problems related to the design of in-flight caging and compromised maternal-offspring interactions. Possibilities for mammalian birth in space, an event that has not yet transpired, are considered. In the aggregate, the results indicate a strong need for new studies of mammalian reproduction and development in space. Habitat development and systematic ground-based testing are important prerequisites to future research with young postnatal rodents in space. Together, the findings support the view that the environment within which young

  1. Ventricular Septal Defect (VSD)

    Science.gov (United States)

    ... Call your doctor if your baby or child: Tires easily when eating or playing Is not gaining ... heart procedures. Risk factors Ventricular septal defects may run in families and sometimes may occur with other ...

  2. Mutation analysis of the candidate genes -, , and in patients with arrhythmogenic right ventricular cardiomyopathy

    DEFF Research Database (Denmark)

    Refsgaard, Lena; Olesen, Morten Salling; Møller, Daniel Vega

    2012-01-01

    INTRODUCTION: Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a genetically determined heart disease characterized by fibrofatty infiltrations in the myocardium, right and/or left ventricular involvement, and ventricular tachyarrhythmias. Although ten genes have been associated with ARVC......, only about 40% of the patients have an identifiable disease-causing mutation. In the present study we aimed at investigating the involvement of the genes SCN1B-SCN4B, FHL1, and LMNA in the pathogenesis of ARVC. METHODS: Sixty-five unrelated patients (55 fulfilling ARVC criteria and 10 borderline cases...... of the variants was non-synonymous. No disease-causing mutations were identified. CONCLUSIONS: In our limited sized cohort the six studied candidate genes were not associated with ARVC....

  3. Uhl’s anomaly: A one and a half ventricular repair in a patient presenting with cardiac arrest

    Directory of Open Access Journals (Sweden)

    Reginald Chounoune

    2018-01-01

    Full Text Available Uhl’s anomaly, first reported in 1952, is an extremely rare congenital cardiac defect characterized by partial or complete loss of the right ventricular myocardium and unknown etiology. Fewer than 100 cases have been described. The response to medical management is poor and there is no known ideal surgical approach or timing for treatment. We report the case of a previously active adolescent male presenting with cardiac arrest, who underwent successful bidirectional cavopulmonary anastomosis (“Glenn” anastomosis with right atrial reduction and right ventricular free wall plication.

  4. Left ventricular function in right ventricular overload

    International Nuclear Information System (INIS)

    Iwanaga, Shiro; Handa, Shunnosuke; Abe, Sumihisa; Onishi, Shohei; Nakamura, Yoshiro; Kunieda, Etsuo; Ogawa, Koichi; Kubo, Atsushi

    1989-01-01

    This study clarified regional and global functions of the distorted left ventricle due to right ventricular overload by gated radionuclide ventriculography (RNV). Cardiac catheterization and RNV were performed in 13 cases of atrial septal defect (ASD), 13 of pure mitral stenosis (MS), 10 of primary pulmonary hypertension (PPH), and 10 of normal subjects (NL). Right ventricular systolic pressure (RVSP) was 32.9±13.9, 45.0±12.2, 88.3±17.1, and 21.2±4.5 mmHg, respectively. The end-systolic LAO view of the left ventricle was halved into septal and free-wall sides. The end-diastolic halves were determined in the same plane. Ejection fractions of the global left ventricle (LVEF), global right ventricle (RVEF), the septal half of the left ventricle (SEPEF), and the free-wall half of the left ventricle (FWEF) were obtained. LVEF was 56.8±9.8% in NL, 52.8±10.5% in ASD, and 49.5±12.9% in PPH. In MS, LVEF (47.0±13.0%) was smaller than those in the other groups. RVEF was 37.0±5.2% in NL, 43.7±15.5% in ASD, and 32.8±11.5% in MS. In PPH, RVEF (25.0±10.6%) was smaller than those in the other groups. SEPEF was smaller in ASD (42.5±13.2%), MS (40.4±13.1%), PPH (40.5±12.5%) than in NL (53.5±8.5%). Systolic function of the septal half of the left ventricle was disturbed by right ventricular overload. RVEF (r=-0.35, p<0.05) and SEPEF (r=-0.51, p<0.01) had negative correlations with RVSP. As RVSP rose, systolic function of the septal half of the left ventricle was more severely disturbed. FWEF was the same among the four groups; NL (57.0±12.6%), ASD (48.6±15.2%), MS (50.5±12.0%), and PPH (51.1±12.3%). There was a good correlation between SEPEF and LVEF in NL (r=0.81), although in PPH this correlation was poor (r=0.64). These data showed that the distorted left ventricular due to right ventricular overload maintains its global function with preserved function of the free-wall side. (J.P.N.)

  5. The possibilities of using scale-selective polarization cartography in diagnostics of myocardium pathologies

    Science.gov (United States)

    Ushenko, Yu. A.; Wanchuliak, O. Y.

    2013-06-01

    The optical model of polycrystalline networks of myocardium protein fibrils is presented. The technique of determining the coordinate distribution of polarization azimuth of the points of laser images of myocardium histological sections is suggested. The results of investigating the interrelation between the values of statistical (statistical moments of the 1st-4th order) parameters are presented which characterize distributions of wavelet-coefficients polarization maps of myocardium layers and death reasons.

  6. Homogenization of Mammalian Cells.

    Science.gov (United States)

    de Araújo, Mariana E G; Lamberti, Giorgia; Huber, Lukas A

    2015-11-02

    Homogenization is the name given to the methodological steps necessary for releasing organelles and other cellular constituents as a free suspension of intact individual components. Most homogenization procedures used for mammalian cells (e.g., cavitation pump and Dounce homogenizer) rely on mechanical force to break the plasma membrane and may be supplemented with osmotic or temperature alterations to facilitate membrane disruption. In this protocol, we describe a syringe-based homogenization method that does not require specialized equipment, is easy to handle, and gives reproducible results. The method may be adapted for cells that require hypotonic shock before homogenization. We routinely use it as part of our workflow to isolate endocytic organelles from mammalian cells. © 2015 Cold Spring Harbor Laboratory Press.

  7. Rheotaxis guides mammalian sperm

    Science.gov (United States)

    Miki, Kiyoshi; Clapham, David E

    2013-01-01

    Background In sea urchins, spermatozoan motility is altered by chemotactic peptides, giving rise to the assumption that mammalian eggs also emit chemotactic agents that guide spermatozoa through the female reproductive tract to the mature oocyte. Mammalian spermatozoa indeed undergo complex adaptations within the female (the process of capacitation) that are initiated by agents ranging from pH to progesterone, but these factors are not necessarily taxic. Currently, chemotaxis, thermotaxis, and rheotaxis have not been definitively established in mammals. Results Here, we show that positive rheotaxis, the ability of organisms to orient and swim against the flow of surrounding fluid, is a major taxic factor for mouse and human sperm. This flow is generated within 4 hours of sexual stimulation and coitus in female mice; prolactin-triggered oviductal fluid secretion clears the oviduct of debris, lowers viscosity, and generates the stream that guides sperm migration in the oviduct. Rheotaxic movement is demonstrated in capacitated and uncapacitated spermatozoa in low and high viscosity medium. Finally, we show that a unique sperm motion we quantify using the sperm head's rolling rate reflects sperm rotation that generates essential force for positioning the sperm in the stream. Rotation requires CatSper channels, presumably by enabling Ca2+ influx. Conclusions We propose that rheotaxis is a major determinant of sperm guidance over long distances in the mammalian female reproductive tract. Coitus induces fluid flow to guide sperm in the oviduct. Sperm rheotaxis requires rotational motion during CatSper channel-dependent hyperactivated motility. PMID:23453951

  8. Plasma Amino Acid Abnormalities in Chronic Heart Failure. Mechanisms, Potential Risks and Targets in Human Myocardium Metabolism

    Directory of Open Access Journals (Sweden)

    Roberto Aquilani

    2017-11-01

    Full Text Available The goal of this study was to measure arterial amino acid levels in patients with chronic heart failure (CHF, and relate them to left ventricular function and disease severity. Amino acids (AAs play a crucial role for heart protein-energy metabolism. In heart failure, arterial AAs, which are the major determinant of AA uptake by the myocardium, are rarely measured. Forty-one subjects with clinically stable CHF (New York Heart Association (NYHA class II to IV were analyzed. After overnight fasting, blood samples from the radial artery were taken to measure AA concentrations. Calorie (KcalI, protein-, fat-, carbohydrate-intake, resting energy expenditure (REE, total daily energy expenditure (REE × 1.3, and cardiac right catheterization variables were all measured. Eight matched controls were compared for all measurements, with the exception of cardiac catheterization. Compared with controls, CHF patients had reduced arterial AA levels, of which both their number and reduced rates are related to Heart Failure (HF severity. Arterial aspartic acid correlated with stroke volume index (r = 0.6263; p < 0.0001 and cardiac index (r = 0.4243; p = 0.0028. The value of arterial aspartic acid (µmol/L multiplied by the cardiac index was associated with left ventricular ejection fraction (r = 0.3765; p = 0.0076. All NYHA groups had adequate protein intake (≥1.1 g/kg/day and inadequate calorie intake (KcalI < REE × 1.3 was found only in class IV patients. This study showed that CHF patients had reduced arterial AA levels directly related to clinical disease severity and left ventricular dysfunction.

  9. Mismatched regional myocardial uptake between [sup 123]I-BMIPP and [sup 201]Tl SPECT; Comparison between hypertrophic myocardium and dilated myocardium

    Energy Technology Data Exchange (ETDEWEB)

    Otsuka, Makoto; Ichiya, Yuichi; Kuwabara, Yasuo; Sasaki, Masayuki; Fukumura, Toshimitsu; Masuda, Kouji; Ejima, Junichi; Tsuda, Yasuo (Kyushu Univ., Fukuoka (Japan). Faculty of Medicine)

    1992-07-01

    The distribution of a new myocardial fatty acid metabolic agent [sup 123]I-BMIPP was compared in 6 each patients with hypertrophic myocardium (4 cases of hypertensive heart disease and 2 of hypertrophic cardiomyopathy) and dilated myocardium (4 of dilated type of valvular heart disease and 2 of dilated cardiomyopathy) with that of [sup 201]Tl. Mismatched regional myocardial uptake between [sup 123]I-BMIPP and [sup 201]Tl SPECT was observed in all of the hypertrophic myocardium, however no but one in the dilated myocardium. Relative increase or decrease in regional BMIPP from the images of 20 min and to those of 4 h was observed in 3 cases of the hypertrophic myocardium. FDG-PET was performed in 2 cases of the hypertrophic myocardium. The distribution of FDG was different from neither those of BMIPP nor Tl in a hypertrophic cardiomyopathy case with the reserved distribution of BMIPP and Tl. Although more investigations are necessary, we concluded that [sup 123]I-BMIPP is a promising radiopharmaceutical for evaluating myocardial fatty acid metabolism in hypertrophic myocardium. (author).

  10. The comparison of nitroglycerin interventional dual-isotope myocardium perfusion imaging and 201Tl re-injection imaging to detect viable myocardium

    International Nuclear Information System (INIS)

    Gao Zhou; Shi yu; Chen Hongyan; Jia Shaowei

    2002-01-01

    Objective: Employing the differences in physical properties of 99m Tc-MIBI and 201 Tl, the authors discuss the contrast result of nitroglycerin interventional dual-isotope myocardium perfusion imaging and 201 Tl re-injection imaging to detect viable myocardium so that authors can enhance the image quality and shorten the examination time. Method: 34 OMI patients took the 99m Tc-MIBI and 201 Tl dual-isotope myocardium perfusion imaging and 201 Tl re-injection imaging respectively in two weeks. During the peak of normal dipyridamole stress i.v. 201 Tl 100 MBq was given and myocardium imaging was taken 15 min later. The dual-isotope group was given nitroglycerin 1mg under the tongue. Five min later, i.v. 99m Tc-MIBI 1110 mBq was given. In 201 Tl re-injection group i.v. 201 Tl 40 MBq was given 4 hour later and were imaged. Among the 34 OMI patients, 19 patients undertook another 99m Tc-MIBI static imaging. Results: There are no obvious differences between nitroglycerin interventional dual-isotope myocardium perfusion imaging and 201 Tl re-injection imaging in detection rate of viable myocardium, χ 2 =0.823, p>0.25. But they have great difference in perfusion changed sectional myocardium absorb rate, t=2.73, p 2 =27.867, p 201 Tl re-injection imaging

  11. Leading ventricular cardiomyocytes

    OpenAIRE

    Rosero Salazar, Doris Haydee; Ortiz Salaza, Mario Alejandro; Monsalve, Liliana Salazar

    2015-01-01

    Objetivo: Exponer las características histológicas y funcionales que se presentan en el tejido muscular estriado cardiaco especializado en la conducción del estímulo eléctrico y sus implicaciones actuales en las arritmias cardiacas. Materiales y métodos: Se seleccionaron publicaciones en revistas indexadas en las bases PubMed, Wiley, Ovid-Medline y Science Direct. Los descriptores MESH utilizados para la búsqueda fueron cardiac myocytes, myocardium, heart conduction system. Se acoplaron los c...

  12. [The protective action of nimodipine on the ischemic myocardium].

    Science.gov (United States)

    Tsorin, I B; Kazanova, G V; Kirsanova, G Iu; Chirkova, E Iu; Chichkanov, G G

    1992-01-01

    The experiments with unconscious cats and dogs have demonstrated that the calcium antagonist nimodipine has a profound anti-ischemic property. The drug reduces the average value of ST-segment elevation in multiple epicardial ECG leads, during acute myocardial ischemia. Nimodipine maintains cardiac pump and contractile functions, elevates ATP levels in the arbitrarily intact and ischemic myocardium of the left ventricle during 40-min occlusion and 60-min reperfusion of the coronary artery. The protective action of the drug is unassociated with enhanced collateral coronary circulation.

  13. Recommendations to realise and interpret the scintigraphy of myocardium perfusion

    International Nuclear Information System (INIS)

    Manrique, A.; Marie, P.Y.

    2003-06-01

    The purpose of these recommendations is to help the physicians in the realization and the interpretation of the tomo-scintigraphies of myocardium perfusion, when this examination is made at the patients having a known or suspected coronary incapacity. These recommendations aim to encourage the practitioners (of nuclear medicine) to reflect and to discuss the procedures applied in their services. These procedures must be also adapted, in every service, to the peculiarities of the environment and to the experiment of each one. (N.C.)

  14. Arrhythmogenic right ventricular dysplasia

    International Nuclear Information System (INIS)

    Vignolo Puglia, W.; Freire Colla, D.; Rivara Urrutia, D.; Lujambio Grene, M.; Arbiza Bruno, T.; Oliveira, G.; Cobas Rodriguez, J.

    1997-01-01

    The arrhythmogenic right ventricular dysplasia is a condition predominantly well defined with arrhythmic events. We analyze three cases diagnosed by the group. These cases were presented as ventricular tachycardia with a morphology of left bundle branch block, presenting one of them aborted sudden death in evolution. The baseline electrocardiogram and signal averaging were abnormal in two of the three cases, like the echocardiogram. The electrophysiological study was able to induce in the three patients with sustained monomorphic ventricular tachycardia morphology of left bundle branch block. The definitive diagnosis was made by right ventriculography in two cases and magnetic resonance imaging in the other. Treatment included antiarrhythmic drugs in the three cases and the placement of an automatic defibrillator which survived a sudden death (Author)

  15. Variability and reproducibility of rubidium-82 kinetic parameters in the myocardium of the anesthetized canine

    International Nuclear Information System (INIS)

    Coxson, P.G.; Brennan, K.M.; Huesman, R.H.

    1995-01-01

    Kinetic analysis of 82 Rb (I) dynamic PET data produces quantitative measures which could be used to evaluate ischemic heart disease. These measures have the potential to generate objective comparisons of different patients or the same patient at different times. To achieve this potential, it is essential to determine the variability and reproducibility of the kinetic parameters. A total of 48 I dynamic PET datasets were acquired from two pure bred beagles. Each animal underwent eight I PET studies with essentially the same protocol for three successive weeks. Data were acquired with the Donner 600-Crystal Positron Tomograph (PET600). In each week, single-slice dynamic I PET datasets were collected with the animal at rest at three different gantry positions separated by 5 mm. Additional dataset were collected after dipyridamole infusion and after administration of aminophylline to induce a return to rest. A two-compartment kinetic model with correction for myocardial vasculature and spillover from the left ventricular blood pool was used to analyze the dynamic datasets. Model parameters for uptake (k 1 ), washout (k 2 ) and vascular fraction (f v ) were estimated in 11-14 myocardial regions of interest (ROIs) using a weighted least-squares criterion. Statistical fluctuation due to the PET acquisition process was minimized by using a relatively high I dose (about 30 mCi) to take advantage of the high count rate capacity of the PET600. The variation in mean k 1 , where the mean is taken over the myocardial ROIs was 10%-20% (Dog 1) and 15%-50% (Dog 2) among the rest studies conducted on the same data. Similar variation was evident in comparing studies in the same animal for different weeks. Spatial and temporal variation in estimates of the uptake rate (k 1 ) of I in the resting myocardium of the anesthetized canine are small in relation to the functional increase in k 1 , following dipyridamole stress. 17 refs., 14 figs

  16. Hyperventilation and circadian rhythm of the electrical stability of rat myocardium

    Directory of Open Access Journals (Sweden)

    Svorc P

    2013-08-01

    Full Text Available Pavol Svorc,1,2 Alexander Marossy,1 Pavol Svorc Jr2 1Department of Physiology, Medical Faculty, Safarik University, Kosice, Slovak Republic; 2Department of Physiology, Medical Faculty, Ostrava University, Ostrava, Czech Republic Objective: Respiratory alkalosis is an extremely common and complicated problem affecting virtually every organ system where the etiologies may be related to pulmonary or cardiovascular disorders. However, there are only few works describing daytime experiments or synchronization of animals to the external environmental periodicity. The aim of the study is to describe the circadian rhythm of the electrical stability of the heart under hyperventilatory conditions. Methods: Circadian rhythms of the electrical stability of the heart, measured by ventricular arrhythmia threshold ([VAT] measurement in 3 hour intervals, were followed during normal artificial ventilation (40 breaths/minute, tidal volume = 1 mL/100 g; n = 17 and hyperventilation (80 breaths/minute, tidal volume = 2 mL/100 g; n = 7 in pentobarbital (40 mg/kg administered intraperitoneally anesthetized female Wistar rats, after 4 week adaptation on the light/dark regime of 12 hour light/12 hour dark (40%–60% humidity, room temperature of 24°C in cages, two animals/cage with access to food and water ad libitum, with the dark period from 18.00h to 06.00h for 4 weeks. Results: The 24 hour course of the VAT showed the highest susceptibility of the rat ventricular myocardium to arrhythmias between 12.00h and 15.00h, and highest resistance between 19.20h and 00.28h (acrophase −338° in time at 22.53h with confidence intervals −2,880° to −70°, under normoxic conditions. Mesor was 2.59 ± 0.53 mA and amplitude 0.33 ± 0.11 mA. Hyperventilation increased the VAT at each interval of the measurement, but did not change the character of its circadian rhythm. Acrophase was on −40° (02.40h, mesor was increased (2.91 mA, and amplitude was decreased (0.13 m

  17. Development of Bioartificial Myocardium Using Stem Cells and Nanobiotechnology Templates

    Directory of Open Access Journals (Sweden)

    Juan Carlos Chachques

    2011-01-01

    Full Text Available Cell-based regenerative therapy is undergoing experimental and clinical trials in cardiology, in order to limit the consequences of decreased contractile function and compliance of damaged ventricles following myocardial infarction. Over 1000 patients have been treated worldwide with cell-based procedures for myocardial regeneration. Cellular cardiomyoplasty seems to reduce the size and fibrosis of infarct scars, limit adverse postischemic remodelling, and improve diastolic function. The development of a bioartificial myocardium is a new challenge; in this approach, tissue-engineered procedures are associated with cell therapy. Organ decellularization for bioscaffolds fabrication is a new investigated concept. Nanomaterials are emerging as the main candidates to ensure the achievement of a proper instructive cellular niche with good drug release/administration properties. Investigating the electrophysiological properties of bioartificial myocardium is the challenging objective of future research, associating a multielectrode network to provide electrical stimulation could improve the coupling of grafted cells and scaffolds with host cardiomyocytes. In summary, until now stem cell transplantation has not achieved clear hemodynamic benefits for myocardial diseases. Supported by relevant scientific background, the development of myocardial tissue engineering may constitute a new avenue and hope for the treatment of myocardial diseases.

  18. Repetitive stimulation of autophagy-lysosome machinery by intermittent fasting preconditions the myocardium to ischemia-reperfusion injury.

    Science.gov (United States)

    Godar, Rebecca J; Ma, Xiucui; Liu, Haiyan; Murphy, John T; Weinheimer, Carla J; Kovacs, Attila; Crosby, Seth D; Saftig, Paul; Diwan, Abhinav

    2015-01-01

    Autophagy, a lysosomal degradative pathway, is potently stimulated in the myocardium by fasting and is essential for maintaining cardiac function during prolonged starvation. We tested the hypothesis that intermittent fasting protects against myocardial ischemia-reperfusion injury via transcriptional stimulation of the autophagy-lysosome machinery. Adult C57BL/6 mice subjected to 24-h periods of fasting, every other day, for 6 wk were protected from in-vivo ischemia-reperfusion injury on a fed day, with marked reduction in infarct size in both sexes as compared with nonfasted controls. This protection was lost in mice heterozygous null for Lamp2 (coding for lysosomal-associated membrane protein 2), which demonstrate impaired autophagy in response to fasting with accumulation of autophagosomes and SQSTM1, an autophagy substrate, in the heart. In lamp2 null mice, intermittent fasting provoked progressive left ventricular dilation, systolic dysfunction and hypertrophy; worsening cardiomyocyte autophagosome accumulation and lack of protection to ischemia-reperfusion injury, suggesting that intact autophagy-lysosome machinery is essential for myocardial homeostasis during intermittent fasting and consequent ischemic cardioprotection. Fasting and refeeding cycles resulted in transcriptional induction followed by downregulation of autophagy-lysosome genes in the myocardium. This was coupled with fasting-induced nuclear translocation of TFEB (transcription factor EB), a master regulator of autophagy-lysosome machinery; followed by rapid decline in nuclear TFEB levels with refeeding. Endogenous TFEB was essential for attenuation of hypoxia-reoxygenation-induced cell death by repetitive starvation, in neonatal rat cardiomyocytes, in-vitro. Taken together, these data suggest that TFEB-mediated transcriptional priming of the autophagy-lysosome machinery mediates the beneficial effects of fasting-induced autophagy in myocardial ischemia-reperfusion injury.

  19. Repetitive stimulation of autophagy-lysosome machinery by intermittent fasting preconditions the myocardium to ischemia-reperfusion injury

    Science.gov (United States)

    Godar, Rebecca J; Ma, Xiucui; Liu, Haiyan; Murphy, John T; Weinheimer, Carla J; Kovacs, Attila; Crosby, Seth D; Saftig, Paul; Diwan, Abhinav

    2015-01-01

    Autophagy, a lysosomal degradative pathway, is potently stimulated in the myocardium by fasting and is essential for maintaining cardiac function during prolonged starvation. We tested the hypothesis that intermittent fasting protects against myocardial ischemia-reperfusion injury via transcriptional stimulation of the autophagy-lysosome machinery. Adult C57BL/6 mice subjected to 24-h periods of fasting, every other day, for 6 wk were protected from in-vivo ischemia-reperfusion injury on a fed day, with marked reduction in infarct size in both sexes as compared with nonfasted controls. This protection was lost in mice heterozygous null for Lamp2 (coding for lysosomal-associated membrane protein 2), which demonstrate impaired autophagy in response to fasting with accumulation of autophagosomes and SQSTM1, an autophagy substrate, in the heart. In lamp2 null mice, intermittent fasting provoked progressive left ventricular dilation, systolic dysfunction and hypertrophy; worsening cardiomyocyte autophagosome accumulation and lack of protection to ischemia-reperfusion injury, suggesting that intact autophagy-lysosome machinery is essential for myocardial homeostasis during intermittent fasting and consequent ischemic cardioprotection. Fasting and refeeding cycles resulted in transcriptional induction followed by downregulation of autophagy-lysosome genes in the myocardium. This was coupled with fasting-induced nuclear translocation of TFEB (transcription factor EB), a master regulator of autophagy-lysosome machinery; followed by rapid decline in nuclear TFEB levels with refeeding. Endogenous TFEB was essential for attenuation of hypoxia-reoxygenation-induced cell death by repetitive starvation, in neonatal rat cardiomyocytes, in-vitro. Taken together, these data suggest that TFEB-mediated transcriptional priming of the autophagy-lysosome machinery mediates the beneficial effects of fasting-induced autophagy in myocardial ischemia-reperfusion injury. PMID:26103523

  20. Prognostic Significance of Remote Myocardium Alterations Assessed by Quantitative Noncontrast T1 Mapping in ST-Segment Elevation Myocardial Infarction.

    Science.gov (United States)

    Reinstadler, Sebastian J; Stiermaier, Thomas; Liebetrau, Johanna; Fuernau, Georg; Eitel, Charlotte; de Waha, Suzanne; Desch, Steffen; Reil, Jan-Christian; Pöss, Janine; Metzler, Bernhard; Lücke, Christian; Gutberlet, Matthias; Schuler, Gerhard; Thiele, Holger; Eitel, Ingo

    2018-03-01

    This study assessed the prognostic significance of remote zone native T1 alterations for the prediction of clinical events in a population with ST-segment elevation myocardial infarction (STEMI) who were treated by primary percutaneous coronary intervention (PPCI) and compared it with conventional markers of infarct severity. The exact role and incremental prognostic relevance of remote myocardium native T1 mapping alterations assessed by cardiac magnetic resonance (CMR) after STEMI remains unclear. We included 255 consecutive patients with STEMI who were reperfused within 12 h after symptom onset. CMR core laboratory analysis was performed to assess left ventricular (LV) function, standard infarct characteristics, and native T1 values of the remote, noninfarcted myocardium. The primary endpoint was a composite of death, reinfarction, and new congestive heart failure within 6 months (major adverse cardiac events [MACE]). Patients with increased remote zone native T1 values (>1,129 ms) had significantly larger infarcts (p = 0.012), less myocardial salvage (p = 0.002), and more pronounced LV dysfunction (p = 0.011). In multivariable analysis, remote zone native T1 was independently associated with MACE after adjusting for clinical risk factors (p = 0.001) or other CMR variables (p = 0.007). In C-statistics, native T1 of remote myocardium provided incremental prognostic information beyond clinical risk factors, LV ejection fraction, and other markers of infarct severity (all p remote zone native T1 to a model of prognostic CMR parameters (ejection fraction, infarct size, and myocardial salvage index) led to net reclassification improvement of 0.82 (95% confidence interval: 0.46 to 1.17; p remote zone alterations by quantitative noncontrast T1 mapping provided independent and incremental prognostic information in addition to clinical risk factors and traditional CMR outcome markers. Remote zone alterations may thus represent a novel therapeutic target and a

  1. The amount of viable and dyssynchronous myocardium is associated with response to cardiac resynchronization therapy: initial clinical results using multiparametric ECG-gated [{sup 18}F]FDG PET

    Energy Technology Data Exchange (ETDEWEB)

    Lehner, Sebastian; Uebleis, Christopher; Haug, Alexander; Bartenstein, Peter [University of Munich, Department of Nuclear Medicine, Munich (Germany); Schuessler, Franziska; Kaeaeb, Stefan; Estner, Heidi [University of Munich, Medical Department I, Munich (Germany); Van Kriekinge, Serge D.; Germano, Guido [UCLA, Cedars-Sinai Medical Center, Los Angeles and David Geffen School of Medicine, Los Angeles, CA (United States); Hacker, Marcus [Medical University of Vienna, Division of Nuclear Medicine, Department of Biomedical Imaging and Image-guided Theraphy, Vienna (Austria)

    2013-12-15

    There is still a significant amount of patients who do not sufficiently respond to cardiac resynchronization therapy (CRT). Previous studies demonstrated that the amount of dyssynchronous myocardium was predictive of response to CRT. Otherwise, non-response is frequently associated with high amounts of scar tissue. The combination of these parameters might yield a more accurate prediction of response. We hypothesized that the probability of a CRT response increases with the presence of high amounts of ''viable and dyssynchronous'' myocardium. A total of 19 patients (17 male, 61 {+-} 10 years) underwent ECG-gated [{sup 18}F]fluorodeoxyglucose (FDG) myocardial positron emission tomography (PET) before CRT device implantation and were followed for 6 months. Response to CRT was defined as clinical improvement of at least one New York Heart Association (NYHA) class in combination with left ventricular (LV) ejection fraction (EF) improvement of >5 %. Twelve responders (71 %) and seven non-responders (29 %) were identified. For each patient bullseye maps of FDG uptake and phase analysis were calculated (QPS/QGS 2012, Cedars-Sinai, Los Angeles, CA, USA) and fused. Amounts of myocardium representing ''viable and synchronous'', ''scar and synchronous'', viable and dyssynchronous or ''scar and dyssynchronous'' myocardium were quantified by planimetric measurements of the fused bullseye maps. Responders by definition showed significant decrease in NYHA class and significant increase of LVEF. Furthermore, a significantly higher amount of viable and dyssynchronous myocardium was found as compared to non-responders (21 {+-} 13 % vs 6 {+-} 5 %; p < 0.05). Combined assessment of myocardial viability and LV dyssynchrony is feasible using multiparametric [{sup 18}F]FDG PET and could improve conventional response prediction criteria for CRT. (orig.)

  2. Probability mapping of scarred myocardium using texture and intensity features in CMR images

    Science.gov (United States)

    2013-01-01

    Background The myocardium exhibits heterogeneous nature due to scarring after Myocardial Infarction (MI). In Cardiac Magnetic Resonance (CMR) imaging, Late Gadolinium (LG) contrast agent enhances the intensity of scarred area in the myocardium. Methods In this paper, we propose a probability mapping technique using Texture and Intensity features to describe heterogeneous nature of the scarred myocardium in Cardiac Magnetic Resonance (CMR) images after Myocardial Infarction (MI). Scarred tissue and non-scarred tissue are represented with high and low probabilities, respectively. Intermediate values possibly indicate areas where the scarred and healthy tissues are interwoven. The probability map of scarred myocardium is calculated by using a probability function based on Bayes rule. Any set of features can be used in the probability function. Results In the present study, we demonstrate the use of two different types of features. One is based on the mean intensity of pixel and the other on underlying texture information of the scarred and non-scarred myocardium. Examples of probability maps computed using the mean intensity of pixel and the underlying texture information are presented. We hypothesize that the probability mapping of myocardium offers alternate visualization, possibly showing the details with physiological significance difficult to detect visually in the original CMR image. Conclusion The probability mapping obtained from the two features provides a way to define different cardiac segments which offer a way to identify areas in the myocardium of diagnostic importance (like core and border areas in scarred myocardium). PMID:24053280

  3. Visualization of atrial myocardium with thallium-201: case report

    International Nuclear Information System (INIS)

    Cowley, M.J.; Coghlan, H.C.; Logic, J.R.

    1977-01-01

    An adult patient evaluated for cyanotic congenital heart disease was found to have pulmonary atresia with intact ventricular septum, hypoplastic right ventricle, and right atrial enlargement. Thallium-201 myocardial imaging before surgical correction showed thallium activity in the right atrium. Following the establishment of a conduit from the right atrium to pulmonary artery, the right-atrial thallium uptake was even more prominent

  4. Protective Effect of Ischemic Postconditioning against Ischemia Reperfusion-Induced Myocardium Oxidative Injury in IR Rats

    Directory of Open Access Journals (Sweden)

    Jiangwei Ma

    2012-03-01

    Full Text Available Brief episodes of myocardial ischemia-reperfusion (IR employed during reperfusion after a prolonged ischemic insult may attenuate the total ischemia-reperfusion injury. This phenomenon has been termed ischemic postconditioning. In the present study, we studied the possible effect of ischemic postconditioning on an ischemic reperfusion (IR-induced myocardium oxidative injury in rat model. Results showed that ischemic postconditioning could improve arrhythmia cordis, reduce myocardium infarction and serum creatin kinase (CK, lactate dehydrogenase (LDH and aspartate transaminase (AST activities in IR rats. In addition, ischemic postconditioning could still decrease myocardium malondialdehyde (MDA level, and increased myocardium Na+-K+-ATPase, Ca2+-Mg2+-ATPase, superoxide dismutase (SOD, catalase (CAT, glutathione peroxidase (GSH-Px and glutathione reductase (GR activities. It can be concluded that ischemic postconditioning possesses strong protective effects against ischemia reperfusion-induced myocardium oxidative injury in IR rats.

  5. Proteomic analysis identifies mitochondrial metabolic enzymes as major discriminators between different stages of the failing human myocardium

    DEFF Research Database (Denmark)

    Urbonavicius, Sigitas; Wiggers, Henrik; Bøtker, Hans Erik

    2009-01-01

    Our aim was to identify patterns in differentially regulated proteins associated with the progression of chronic heart failure. We specifically studied proteomics in chronic reversibly (RDM) and irreversibly dysfunctional myocardium (IRDM), as well as end-stage failing myocardium (ESFM).......Our aim was to identify patterns in differentially regulated proteins associated with the progression of chronic heart failure. We specifically studied proteomics in chronic reversibly (RDM) and irreversibly dysfunctional myocardium (IRDM), as well as end-stage failing myocardium (ESFM)....

  6. BAG3 regulates contractility and Ca2+ homeostasis in adult mouse ventricular myocytes

    OpenAIRE

    Feldman, Arthur M.; Gordon, Jennifer; Wang, JuFang; Song, Jianliang; Zhang, Xue-Qian; Myers, Valerie D.; Tilley, Douglas G.; Gao, Erhe; Hoffman, Nicholas E.; Tomar, Dhanendra; Madesh, Muniswamy; Rabinowitz, Joseph; Koch, Walter J.; Su, Feifei; Khalili, Kamel

    2016-01-01

    Bcl2-associated athanogene 3 (BAG3) is a 575 amino acid anti-apoptotic protein that is constitutively expressed in the heart. BAG3 mutations, including mutations leading to loss of protein, are associated with familial cardiomyopathy. Furthermore, BAG3 levels have been found to be reduced in end-stage non-familial failing myocardium. In contrast to neonatal myocytes in which BAG3 is found in the cytoplasm and involved in protein quality control and apoptosis, in adult mouse left ventricular (...

  7. Myocardium scintiscanning with thallium-201 in case of idiopathic juvenile arteriosclerosis (description of a case and information on further applications of nuclear-medical diagnostic techniques in pediatric cardiology)

    International Nuclear Information System (INIS)

    Hoer, G.; Maul, F.D.; Munz, D.L.; Vettermann, H.

    1985-01-01

    In the field of pediatrics and the related literature, the analysis of myocardial perfusion and ventricular function using myocardium scintiscanning and radionuclide ventriculography is a subject discussed rather rarely, in contrast to the medical examination of adult patients where this is a well-established method. The authors have so far not found any information on the use of scintiscanning methods for the diagnosis of idiopathic juvenile arteriosclerosis and hence take the opportunity to describe a case of recent application of this method. In addition, findings and results are discussed that speak in favour of the use of further nuclear-medical techniques in pediatric cardiology. (orig./MG) [de

  8. Activation of NADPH oxidase mediates increased endoplasmic reticulum stress and left ventricular remodeling after myocardial infarction in rabbits.

    Science.gov (United States)

    Li, Bao; Tian, Jing; Sun, Yi; Xu, Tao-Rui; Chi, Rui-Fang; Zhang, Xiao-Li; Hu, Xin-Ling; Zhang, Yue-An; Qin, Fu-Zhong; Zhang, Wei-Fang

    2015-05-01

    Nicotinamide adenine dinucleotide 3-phosphate (NADPH) oxidase activity and endoplasmic reticulum (ER) stress are increased after myocardial infarction (MI). In this study, we proposed to test whether activation of the NADPH oxidase in the remote non-infarcted myocardium mediates ER stress and left ventricular (LV) remodeling after MI. Rabbits with MI or sham operation were randomly assigned to orally receive an NADPH oxidase inhibitor apocynin or placebo for 30 days. The agents were administered beginning at 1 week after surgery. MI rabbits exhibited decreases in LV fractional shortening, LV ejection fraction and the first derivative of the LV pressure rise, which were abolished by apocynin treatment. NADPH oxidase Nox2 protein and mRNA expressions were increased in the remote non-infarcted myocardium after MI. Immunolabeling further revealed that Nox2 was increased in cardiac myocytes in the remote myocardium. The apocynin treatment prevented increases in the Nox2 expression, NADPH oxidase activity, oxidative stress, myocyte apoptosis and GRP78, CHOP and cleaved caspase 12 protein expression in the remote myocardium. The apocynin treatment also attenuated increases in myocyte diameter and cardiac fibrosis. In cultured H9C2 cardiomyocytes exposed to angiotensin II, an important stimulus for post-MI remodeling, Nox2 knockdown with siRNA significantly inhibited angiotensin II-induced NADPH oxidase activation, reactive oxygen species and GRP78 and CHOP protein expression. We conclude that NADPH oxidase inhibition attenuates increased ER stress in the remote non-infarcted myocardium and LV remodeling late after MI in rabbits. These findings suggest that the activation of NADPH oxidase in the remote non-infarcted myocardium mediates increased ER stress, contributing to myocyte apoptosis and LV remodeling after MI. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Temperature dependence of the kinetics of isometric myocardium relaxation

    Energy Technology Data Exchange (ETDEWEB)

    Izakov, V.Ya.; Bykov, B.L.; Kimmelman, I.Ya.

    1981-11-01

    The dependence of the exponential decay constant expressing the isometric relaxation of the myocardium on temperature is investigated in animals with various specific contents of myocardial sarcoplasmic reticulum. Experiments were performed on cardiac ventricles and atria isolated from rabbits, frogs and turtles and electrically stimulated to produce maximal contraction at temperatures from 10 to 35 C. Arrhenius plots derived from the data are found to be linear in the myocardia of the rabbit and frog, with a greater activation energy for the relaxation found in the rabbit. The Arrhenius plot for the turtle, which has a sarcoplasmic reticulum content intermediate between those of the frog and rabbit, corresponds to two straight lines with different activation energies. Results thus support the hypothesis of two separate mechanisms of calcium removal, involving the sarcoplasmic reticulum and cellular membrane, in muscle relaxation.

  10. Mammalian cell biology

    International Nuclear Information System (INIS)

    Elkind, M.M.

    1975-01-01

    Studies of the action of N-ethylmaleimide (NEM), as an inhibitor of repair of x radioinduced injuries were extended from synchronous Chinese hamster cells to synchronous human HeLa cells. These studies showed a similar mode of action in both cell types lending support to the notion that conclusions may be extracted from such observations that are of fairly general applicability to mammalian cells. Radiation studies with NEM are being extended to hypoxic cells to inquire if NEM is effective relative to oxygen-independent damage. Observations relative to survival, DNA synthesis, and DNA strand elongation resulting from the addition products to DNA when cells were exposed to near uv in the presence of psoralen were extended. (U.S.)

  11. Computational model based approach to analysis ventricular arrhythmias: Effects of dysfunction calcium channels

    Science.gov (United States)

    Gulothungan, G.; Malathi, R.

    2018-04-01

    Disturbed sodium (Na+) and calcium (Ca2+) handling is known to be a major predisposing factor for life-threatening cardiac arrhythmias. Cardiac contractility in ventricular tissue is prominent by Ca2+ channels like voltage dependent Ca2+ channels, sodium-calcium exchanger (Na+-Ca2+x) and sacroplasmicrecticulum (SR) Ca2+ pump and leakage channels. Experimental and clinical possibilities for studying cardiac arrhythmias in human ventricular myocardium are very limited. Therefore, the use of alternative methods such as computer simulations is of great importance. Our aim of this article is to study the impact on action potential (AP) generation and propagation in single ventricular myocyte and ventricular tissue under different dysfunction Ca2+ channels condition. In enhanced activity of Na+-Ca2+x, single myocyte produces AP duration (APD90) and APD50 is significantly smaller (266 ms and 235 ms). Its Na+-Ca2+x current at depolarization is increases 60% from its normal level and repolarization current goes more negative (nonfailing= -0.28 pA/pF and failing= -0.47 pA/pF). Similarly, same enhanced activity of Na+-Ca2+x in 10 mm region of ventricular sheet, raises the plateau potential abruptly, which ultimately affects the diastolic repolarization. Compare with normal ventricular sheet region of 10 mm, 10% of ventricular sheet resting state is reduces and ventricular sheet at time 250 ms is goes to resting state very early. In hypertrophy condition, single myocyte produces APD90 and APD50 is worthy of attention smaller (232 mS and 198 ms). Its sodium-potassium (Na+-K+) pump current is 75% reduces from its control conditions (0.13 pA/pF). Hypertrophy condition, 50% of ventricular sheet is reduces to minimum plateau potential state, that starts the repolarization process very early and reduces the APD. In a single failing SR Ca2+ channels myocyte, recovery of Ca2+ concentration level in SR reduces upto 15% from its control myocytes. At time 290 ms, 70% of ventricular sheet

  12. Vertebrate brains and evolutionary connectomics: on the origins of the mammalian ‘neocortex’

    Science.gov (United States)

    Karten, Harvey J.

    2015-01-01

    The organization of the non-mammalian forebrain had long puzzled neurobiologists. Unlike typical mammalian brains, the telencephalon is not organized in a laminated ‘cortical’ manner, with distinct cortical areas dedicated to individual sensory modalities or motor functions. The two major regions of the telencephalon, the basal ventricular ridge (BVR) and the dorsal ventricular ridge (DVR), were loosely referred to as being akin to the mammalian basal ganglia. The telencephalon of non-mammalian vertebrates appears to consist of multiple ‘subcortical’ groups of cells. Analysis of the nuclear organization of the avian brain, its connections, molecular properties and physiology, and organization of its pattern of circuitry and function relative to that of mammals, collectively referred to as ‘evolutionary connectomics’, revealed that only a restricted portion of the BVR is homologous to the basal ganglia of mammals. The remaining dorsal regions of the DVR, wulst and arcopallium of the avian brain contain telencephalic inputs and outputs remarkably similar to those of the individual layers of the mammalian ‘neocortex’, hippocampus and amygdala, with instances of internuclear connections strikingly similar to those found between cortical layers and within radial ‘columns’ in the mammalian sensory and motor cortices. The molecular properties of these ‘nuclei’ in birds and reptiles are similar to those of the corresponding layers of the mammalian neocortex. The fundamental pathways and cell groups of the auditory, visual and somatosensory systems of the thalamus and telencephalon are homologous at the cellular, circuit, network and gene levels, and are of great antiquity. A proposed altered migration of these homologous neurons and circuits during development is offered as a mechanism that may account for the altered configuration of mammalian telencephalae. PMID:26554047

  13. Three dimensional endo-cardiovascular volume-rendered cine computed tomography of isolated left ventricular apical hypoplasia; A case report and literature review

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Sun Hwa; Kim, Yang Min; Lee, Hyun Jong [Sejong General Hospital, Bucheon (Korea, Republic of)

    2016-02-15

    We report multidetector computed tomography (MDCT) and cardiac magnetic resonance (CMR) findings of a 34-year-old female with isolated left ventricular apical hypoplasia. The MDCT and CMR scans displayed a spherical left ventricle (LV) with extensive fatty infiltration within the myocardium at the apex, interventricular septum and inferior wall, anteroapical origin of the papillary muscle, right ventricle wrapping around the deficient LV apex, and impaired systolic function. MDCT visualized morphologic and also functional findings of this unique cardiomyopathy.

  14. The alteration of interelemental ratios in myocardium under the congenital heart disease (SRXRF)

    International Nuclear Information System (INIS)

    Trunova, V.A.; Zvereva, V.V.; Okuneva, G.N.; Levicheva, E.N.

    2007-01-01

    It is the myocardium that bears the basic functional loading during heart working, including muscle contractility and enzyme activity. The elemental concentrations in myocardium tissue of heart were determined by SRXRF technique. Our investigation is systematical: the elemental content in each compartment (left and right ventricles, left and right auricles) of hearts of healthy and diseased children (congenital heart diseases, transposition of main vessels (TMV)) was analyzed. The elemental distribution in myocardium of four heart chambers of human fetuses was also analyzed. Following elements were determined: S, Cl, K, Ca, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Br, Rb, Sr. It was revealed that the elemental concentrations in myocardium of both ventricles are almost constant in heart of fetuses and healthy children. The transition from pre-natal study (fetus) to post-natal study is accompanied by the redistribution of chemical elements in myocardium. The higher concentrations of S, Fe, Ca, Sr and Cu in myocardium of children are observed, the content of K, Br, Rb and especially Se is lower than in heart of fetuses. The elemental distribution in myocardium of children TMV is considerably different in comparison with the healthy children: the higher levels of Cu are observed. The content of Se is lower

  15. Left Ventricular Assist Devices

    Directory of Open Access Journals (Sweden)

    Khuansiri Narajeenron

    2017-04-01

    Full Text Available Audience: The audience for this classic team-based learning (cTBL session is emergency medicine residents, faculty, and students; although this topic is applicable to internal medicine and family medicine residents. Introduction: A left ventricular assist device (LVAD is a mechanical circulatory support device that can be placed in critically-ill patients who have poor left ventricular function. After LVAD implantation, patients have improved quality of life.1 The number of LVAD patients worldwide continues to rise. Left-ventricular assist device patients may present to the emergency department (ED with severe, life-threatening conditions. It is essential that emergency physicians have a good understanding of LVADs and their complications. Objectives: Upon completion of this cTBL module, the learner will be able to: 1 Properly assess LVAD patients’ circulatory status; 2 appropriately resuscitate LVAD patients; 3 identify common LVAD complications; 4 evaluate and appropriately manage patients with LVAD malfunctions. Method: The method for this didactic session is cTBL.

  16. Ventricular premature contraction in hypertrophic cardiomyopathy and essential hypertension with left ventricular hypertrophy

    International Nuclear Information System (INIS)

    Kobiki, Naoki

    1989-01-01

    In order to investigate the relationship of different morbid states of the hypertrophied myocardium to the appearance of ventricular premature contraction (VPC), we compared the VPC findings from Holter ECG with those of UCG and stress thallium-201 myocardial SPECT scintigraphy (stress scinti) in 31 patients with hypertrophic cardiomyopathy (HCM) and 20 with essential hypertension (HT). The HCM patients consisted of 21 with asymmetric hypertrophy (ASH), 3 with symmetric hypertrophy (SH), and 7 with apical hypertrophy (APH). We recognized positive findings on the stress scinti such as fixed perfusion defect (FD) or reversible perfusion defect (RD) in 11 patients (ASH 10, APH 1) out of 31 patients with HCM (35%). Positive findings were observed in only one patient out of 20 with HT (5%). We recognized a high grade VPC (grade 4a and 4b of Lown's criteria) in 8 of 11 scinti positive patients with HCM (ASH 7, APH 1)(73%), while high grade VPC appeared in 5 (all of them are ASH) out of 20 scinti negative patients with HCM (25%). Therefore, these findings suggest that high grade VPCs in HCM occur in relation to a myocardial perfusion defect. (author)

  17. Ebstein’s Anomaly, Left Ventricular Noncompaction, and Sudden Cardiac Death

    Directory of Open Access Journals (Sweden)

    Michael McGee

    2015-01-01

    Full Text Available Ebstein’s anomaly is a congenital disorder characterized by apical displacement of the septal leaflet of the tricuspid valve. Ebstein’s anomaly may be seen in association with other cardiac conditions, including patent foramen ovale, atrial septal defect, and left ventricular noncompaction (LVNC. LVNC is characterized by increased trabeculation within the left ventricular apex. Echocardiography is often used to diagnose LVNC; however, magnetic resonance (MR imaging offers superior characterization of the myocardium. We report a case of sudden cardiac death in a patient with Ebstein’s anomaly with unrecognized LVNC noted on post mortem examination with screening documenting the presence of LVNC in one of the patient’s twin sons.

  18. Analysis of the influence factors on myocardium to liver ratio of 99Tcm-MIBI

    International Nuclear Information System (INIS)

    Zhang Jinming; Tian Jiahe; Zhao Xiaoguang; Liu Zilai; Wang Shengcai

    1995-01-01

    The resting myocardial SPECT by different MIBI kits for 113 cases of normal and ischemic heart disease is performed. The preparation of kits, reducing agents, and the time of imaging are checked using myocardium to liver (M/L) ratio as the parameter of myocardium uptake of MIBI. It shows that MIBI uptake of myocardium has no relation with the reducing agents, the time of imaging between 60-120 min, while M/L ratio varied in every individual case. The ratio of M/L has also no relation to the Radiochemical Purity (RCP) as long as RCP is more than 95%

  19. Remodeling after acute myocardial infarction: mapping ventricular dilatation using three dimensional CMR image registration

    Directory of Open Access Journals (Sweden)

    O’Regan Declan P

    2012-06-01

    Full Text Available Abstract Background Progressive heart failure due to remodeling is a major cause of morbidity and mortality following myocardial infarction. Conventional clinical imaging measures global volume changes, and currently there is no means of assessing regional myocardial dilatation in relation to ischemic burden. Here we use 3D co-registration of Cardiovascular Magnetic Resonance (CMR images to assess the long-term effects of ischemia-reperfusion injury on left ventricular structure after acute ST-elevation myocardial infarction (STEMI. Methods Forty six patients (age range 33–77 years underwent CMR imaging within 7 days following primary percutaneous coronary intervention (PPCI for acute STEMI with follow-up at one year. Functional cine imaging and Late Gadolinium Enhancement (LGE were segmented and co-registered. Local left ventricular wall dilatation was assessed by using intensity-based similarities to track the structural changes in the heart between baseline and follow-up. Results are expressed as means, standard errors and 95% confidence interval (CI of the difference. Results Local left ventricular remodeling within infarcted myocardium was greater than in non-infarcted myocardium (1.6% ± 1.0 vs 0.3% ± 0.9, 95% CI: -2.4% – -0.2%, P = 0.02. One-way ANOVA revealed that transmural infarct thickness had a significant effect on the degree of local remodeling at one year (P 20% (4.8% ± 1.4 vs −0.15% ± 1.2, 95% CI: -8.9% – -0.9%, P = 0.017. Conclusions The severity of ischemic injury has a significant effect on local ventricular wall remodeling with only modest dilatation observed within non-ischemic myocardium. Limitation of chronic remodeling may therefore depend on therapies directed at modulating ischemia-reperfusion injury. CMR co-registration has potential for assessing dynamic changes in ventricular structure in relation to therapeutic interventions.

  20. Inhibition of Rac1 reduces store overload-induced calcium release and protects against ventricular arrhythmia.

    Science.gov (United States)

    Zhang, Lili; Lu, Xiangru; Gui, Le; Wu, Yan; Sims, Stephen M; Wang, Guoping; Feng, Qingping

    2016-08-01

    Rac1 is a small GTPase and plays key roles in multiple cellular processes including the production of reactive oxygen species (ROS). However, whether Rac1 activation during myocardial ischaemia and reperfusion (I/R) contributes to arrhythmogenesis is not fully understood. We aimed to study the effects of Rac1 inhibition on store overload-induced Ca(2+) release (SOICR) and ventricular arrhythmia during myocardial I/R. Adult Rac1(f/f) and cardiac-specific Rac1 knockdown (Rac1(ckd) ) mice were subjected to myocardial I/R and their electrocardiograms (ECGs) were monitored for ventricular arrhythmia. Myocardial Rac1 activity was increased and ventricular arrhythmia was induced during I/R in Rac1(f/f) mice. Remarkably, I/R-induced ventricular arrhythmia was significantly decreased in Rac1(ckd) compared to Rac1(f/f) mice. Furthermore, treatment with Rac1 inhibitor NSC23766 decreased I/R-induced ventricular arrhythmia. Ca(2+) imaging analysis showed that in response to a 6 mM external Ca(2+) concentration challenge, SOICR was induced with characteristic spontaneous intracellular Ca(2+) waves in Rac1(f/f) cardiomyocytes. Notably, SOICR was diminished by pharmacological and genetic inhibition of Rac1 in adult cardiomyocytes. Moreover, I/R-induced ROS production and ryanodine receptor 2 (RyR2) oxidation were significantly inhibited in the myocardium of Rac1(ckd) mice. We conclude that Rac1 activation induces ventricular arrhythmia during myocardial I/R. Inhibition of Rac1 suppresses SOICR and protects against ventricular arrhythmia. Blockade of Rac1 activation may represent a new paradigm for the treatment of cardiac arrhythmia in ischaemic heart disease. © 2016 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

  1. Localization of two mammalian cyclin dependent kinases during mammalian meiosis

    NARCIS (Netherlands)

    Ashley, T.; Walpita, D.; de rooij, D. G.

    2001-01-01

    Mammalian meiotic progression, like mitotic cell cycle progression, is regulated by cyclins and cyclin dependent kinases (CDKs). However, the unique requirements of meiosis (homologous synapsis, reciprocal recombination and the dual divisions that segregate first homologues, then sister chromatids)

  2. Mammalian Gut Immunity

    Science.gov (United States)

    Chassaing, Benoit; Kumar, Manish; Baker, Mark T.; Singh, Vishal; Vijay-Kumar, Matam

    2016-01-01

    The mammalian intestinal tract is the largest immune organ in the body and comprises cells from non-hemopoietic (epithelia, Paneth cells, goblet cells) and hemopoietic (macrophages, dendritic cells, T-cells) origin, and is also a dwelling for trillions of microbes collectively known as the microbiota. The homeostasis of this large microbial biomass is prerequisite to maintain host health by maximizing beneficial symbiotic relationships and minimizing the risks of living in such close proximity. Both microbiota and host immune system communicate with each other to mutually maintain homeostasis in what could be called a “love–hate relationship.” Further, the host innate and adaptive immune arms of the immune system cooperate and compensate each other to maintain the equilibrium of a highly complex gut ecosystem in a stable and stringent fashion. Any imbalance due to innate or adaptive immune deficiency or aberrant immune response may lead to dysbiosis and low-grade to robust gut inflammation, finally resulting in metabolic diseases. PMID:25163502

  3. Mammalian cell biology

    International Nuclear Information System (INIS)

    Anon.

    1976-01-01

    Progress is reported on studies of the molecular biology and functional changes in cultured mammalian cells following exposure to x radiation, uv radiation, fission neutrons, or various chemical environmental pollutants alone or in combinations. Emphasis was placed on the separate and combined effects of polycyclic aromatic hydrocarbons released during combustion of fossil fuels and ionizing and nonionizing radiations. Sun lamps, which emit a continuous spectrum of near ultraviolet light of 290 nm to 315 nm were used for studies of predictive cell killing due to sunlight. Results showed that exposure to uv light (254 nm) may not be adequate to predict effects produced by sunlight. Data are included from studies on single-strand breaks and repair in DNA of cultured hamster cells exposed to uv or nearultraviolet light. The possible interactions of the polycyclic aromatic hydrocarbon 7,12-dimethylbenz(a)-anthracene (DmBA) alone or combined with exposure to x radiation, uv radiation (254 nm) or near ultraviolet simulating sunlight were compared for effects on cell survival

  4. Cryopreservation of mammalian semen.

    Science.gov (United States)

    Curry, Mark R

    2007-01-01

    Mammalian spermatozoa were among the very first cells to be successfully cryopreserved and over the last five decades the use of frozen-thawed semen for artificial insemination has come to play an important role in domestic livestock production. More recently, semen freezing has increasingly been utilized in the establishment of genetic resource banks for endangered species. Semen is collected, most commonly either by use of an artificial vagina or by electroejaculation of an anaesthetized animal, and basic sperm parameters assessed. Semen is extended using a TEST-egg yolk-glycerol diluent, packaged in 0.25-mL plastic straws and slowly cooled to 5 degrees C over a period of 1-2 h. Cooled straws are frozen by suspending within liquid nitrogen vapor above the liquid nitrogen surface before plunging into the liquid phase. Straws are thawed briefly in air before immersing in a 35 degrees C water bath for 15 s, and often are used directly for insemination without any further processing.

  5. mammalian brain system

    Directory of Open Access Journals (Sweden)

    Alan Kania

    2014-06-01

    Full Text Available Relaxin-3, a member of the relaxin peptide family, was discovered in 2001 as a homologue of relaxin – a well-known reproductive hormone. However, it is the brain which turned out to be a major expression site of this newly discovered peptide. Both its molecular structure and expression pattern were shown to be very conserved among vertebrates. Extensive research carried out since the discovery of relaxin-3 contributed to the significant progress in our knowledge regarding this neuropeptide. The endogenous relaxin-3 receptor (RXFP3 was identified and the anatomy of the yet uncharacterized mammalian brain system was described, with nucleus incertus as the main center of relaxin-3 expression. Not only its diffusive projections throughout the whole brain, which reach various brain structures such as the hippocampus, septum, intergeniculate leaflet or amygdala, but also functional studies of the relaxin-3/RXFP3 signaling system, allowed this brain network to be classified as one of the ascending nonspecific brain systems. Thus far, research depicts the connection of relaxin-3 with phenomena such as feeding behavior, spatial memory, sleep/wake cycle or modulation of pituitary gland hormone secretion. Responsiveness of relaxin-3 neurons to stress factors and the strong orexigenic effect exerted by this peptide suggest its participation in modulation of feeding by stress, in particular of the chronic type. The discovery of relaxin-3 opened a new research field which will contribute to our better understanding of the neurobiological basis of feeding disorders.

  6. Reduced Sodium Current in the Lateral Ventricular Wall Induces Inferolateral J-Waves.

    Science.gov (United States)

    Meijborg, Veronique M F; Potse, Mark; Conrath, Chantal E; Belterman, Charly N W; De Bakker, Jacques M T; Coronel, Ruben

    2016-01-01

    J-waves in inferolateral leads are associated with a higher risk for idiopathic ventricular fibrillation. We aimed to test potential mechanisms (depolarization or repolarization dependent) responsible for inferolateral J-waves. We hypothesized that inferolateral J-waves can be caused by regional delayed activation of myocardium that is activated late during normal conditions. Computer simulations were performed to evaluate how J-point elevation is influenced by reducing sodium current conductivity (GNa), increasing transient outward current conductivity (Gto), or cellular uncoupling in three predefined ventricular regions (lateral, anterior, or septal). Two pig hearts were Langendorff-perfused with selective perfusion with a sodium channel blocker of lateral or anterior/septal regions. Volume-conducted pseudo-electrocardiograms (ECG) were recorded to detect the presence of J-waves. Epicardial unipolar electrograms were simultaneously recorded to obtain activation times (AT). Simulation data showed that conduction slowing, caused by reduced sodium current, in lateral, but not in other regions induced inferolateral J-waves. An increase in transient outward potassium current or cellular uncoupling in the lateral zone elicited slight J-point elevations which did not meet J-wave criteria. Additional conduction slowing in the entire heart attenuated J-waves and J-point elevations on the ECG, because of masking by the QRS. Experimental data confirmed that conduction slowing attributed to sodium channel blockade in the left lateral but not in the anterior/septal ventricular region induced inferolateral J-waves. J-waves coincided with the delayed activation. Reduced sodium current in the left lateral ventricular myocardium can cause inferolateral J-waves on the ECG.

  7. Effect of L-glutamate on the metabolic recovery of the myocardium after K sup (+)- induced cardioplegic arrest. Die effek van L-glutamaat op die metaboliese herstel van die miokard na K sup (+)-geinduseerde kardioplegiese arres

    Energy Technology Data Exchange (ETDEWEB)

    Neethling, W M.L.

    1984-01-01

    A study was undertaken to determine the effect of L-glutamate on the metabolic recovery of the myocardium after K sup (+)-induced cardioplegic arrest. Isolated rat hearts and intact dog hearts were subjected to a K sup (+)-induced cardioplegic period of 60 minutes. Preservation temperature was kept constant at 26 degrees Celsius during the entire cardioplegic period. Different concentrations of L-glutamate were added to a dose of secondary cardioplegia. Several parameters, such as isotonic contraction, left ventricular function, enzymatic changes, coronary vascular resistance (coronary flow), oedema, re-animation time-interval and lactate-release were used to determine the above mentioned effect. Radioactive L-glutamate was used to determine the quantitative uptake and distribution of L-glutamate in the myocardium. Basic spectrophotometric methods were used to determine the concentrations of creatine phosphokinase, lactic dehydrogenase and lactate. Standard differential separation methods were used to divide myocardial samples into the different tissue and cytologic fractions. Biophysical methods were used to measure radioactivity in the respective tissue and cytologic fractions. Experimental results were statistically analyzed according to analysis of variance and at-test (Tukey's Test). Preliminary findings stress the important role of L-glutamate in the metabolic recovery of the myocardium after K sup (+)-induced arrest and consequently the positive contribution in the search for the best method of myocardial preservation during cardiac surgery.

  8. Systolic left ventricular function according to left ventricular concentricity and dilatation in hypertensive patients

    DEFF Research Database (Denmark)

    Bang, Casper; Gerdts, Eva; Aurigemma, Gerard P

    2013-01-01

    Left ventricular hypertrophy [LVH, high left ventricular mass (LVM)] is traditionally classified as concentric or eccentric based on left ventricular relative wall thickness. We evaluated left ventricular systolic function in a new four-group LVH classification based on left ventricular dilatation...... [high left ventricular end-diastolic volume (EDV) index and concentricity (LVM/EDV)] in hypertensive patients....

  9. Muerte súbita por conmoción cardíaca (Commotio cordis asociada a miocardio no compactado Sudden death due to commotio cordis associated to non compacted myocardium

    Directory of Open Access Journals (Sweden)

    Analía Aquieri

    2011-12-01

    Full Text Available El miocardio no compactado es una rara miocardiopatía congénita caracterizada por la presencia de múltiples y prominentes trabeculaciones profundas en la pared ventricular que definen hendiduras comunicantes con el compartimiento ventricular principal. Es una entidad de baja incidencia y prevalencia que se diagnostica mediante estudios de imágenes como el ecocardiograma Doppler (ED, la tomografía computarizada multicorte (TCM y la resonancia magnética cardíaca (RMC. Puede ser asintomática o manifestarse mediante arritmias, insuficiencia cardíaca o eventos tromboembólicos. Se presenta el caso de un hombre de 33 años, asintomático, que durante la práctica deportiva sufre una conmoción cardíaca (commotio cordis que le produce un paro cardiorrespiratorio. El electrocardiograma mostró un ritmo de aleteo ventricular que requirió cardiodesfibrilación eléctrica. En un ED efectuado inicialmente no se observaron anormalidades significativas, pero otro ED, una TCM y una RMN obtenidos luego del alta, certificaron el hallazgo de miocardio no compactado aislado, descartando coronariopatía. Recibió tratamiento beta bloqueante y antiagregante y se discutió la colocación del cardiodesfibrilador implantable. Se plantea la fisiopatología de la asociación de estas dos infrecuentes y potencialmente letales afecciones.Non compact of the left ventricular myocardium is a rare congenital cardiomyopathy characterized by the presence of multiple and prominent deep trabeculations in the ventricular wall, that define recesses communicated with the main ventricular chamber. This is a condition with low incidence and prevalence, diagnosed through imaging techniques such as Doppler echocardiogram (DE, multi-slice computed tomography (MSCT or magnetic resonance imaging (MRI. Clinically, it may be asymptomatic or manifested by cardiac arrhythmias, heart failure or thromboembolism. This is a report on a 33 year old asymptomatic man who suffered a blow on

  10. Effects of perfusion detect on the measurement of left ventricular mass, ventricular volume and post-stress left ventricular ejection fraction in gated myocardial perfusion SPECT

    International Nuclear Information System (INIS)

    Ahn, Byeong Cheol; Bae, Sun Keun; Lee, Sang Woo; Jeong, Sin Young; Lee, Jae Tae; Lee, Kyu Bo

    2002-01-01

    The presence of perfusion defect may influence the left ventricular mass (LVM) measurement by quantitative gated myocardial perfusion SPECT (QGS), and ischemic myocardium, usually showing perfusion defect may produce post-stress LV dysfunction. This study was aimed to evaluated the effects of extent and reversibility of perfusion defect on the automatic measurement of LVM by QGS and to investigate the effect of reversibility of perfusion defect on post-stress LV dysfunction. Forty-six patients (male/female=34:12, mean age=64 years) with perfusion defect on myocardial perfusion SPECT underwent rest and post-stress QGS. Forty patients (87%) showed reversible defect. End-diastolic volume (EDV), end-systolic volume (ESV), LV ejection fraction (EF), and LV myocardial volume were obtained from QGS by autoquant program, and LVM was calculated by multiplying the LV myocardial volume by the specific gravity of myocardium. LVMs measured at rest and post-stress QGS showed good correlation, and higher correlation was founded in the subjects with fixed perfusion defect and with small defect (smaller than 20%). There were no significant differences in EDVs, ESVs and EFs between obtained by rest and post-stress QGS in patients with fixed myocardial defect. Whereas, EF obtained by post-stress QGS was lower than that by rest QGS in patients with reversible defect and 10 (25%) of them showed decreases in EF more than 5% in post-stress QGS, as compared to that of rest QGS. Excellent correlations of EDVs, ESVs, EFs between rest and post-stress QGS were noted. Patients with fixed defect had higher correlation between defect can affect LVM measurement by QGS and patients with reversible defect shows post-stress LV dysfunction more frequently than patients with fixed perfusion defect

  11. Chronic Hypoxia Enhances Expression and Activity of Mitochondrial Creatine Kinase and Hexokinase in the Rat Ventricular Myocardium

    Czech Academy of Sciences Publication Activity Database

    Wasková-Arnoštová, P.; Kašparová, D.; Elsnicová, B.; Novotný, J.; Neckář, Jan; Kolář, František; Žurmanová, J.

    2014-01-01

    Roč. 33, č. 2 (2014), s. 310-320 ISSN 1015-8987 R&D Projects: GA AV ČR(CZ) IAAX01110901; GA ČR(CZ) GAP303/12/1162 Grant - others:Univerzita Karlova(CZ) 349211; GA AV ČR(CZ) IAA601110908 Institutional support: RVO:67985823 Keywords : creatine kinase * hexokinase * normobaric hypoxia * left ventricle * right ventricle * mitochondria co-localization Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery Impact factor: 2.875, year: 2014

  12. pH dependence of the isoproterenol-induced /sup 45/Ca net uptake into the ventricular myocardium of rats

    Energy Technology Data Exchange (ETDEWEB)

    Haag, R

    1975-01-01

    Infarction-like or disseminated myocardial necroses can be produced in rats by high doses of isoprotenerol which stimulates the decomposition of energy-rich phosphates to a maximum. The paper shows that acidoses of different genesis (peroral administration of NH/sub 4/Cl, artificial respiration with CO/sub 2/) induced experimentally can inhibit the isoproterenol-induced /sup 45/Ca net uptake and the production of necroses. The findings suggest that Ca/sup + +/ ions play a key role in the production of myocardial necroses which has not been recognized until now - that increased Ca/sup + +/ uptake into damaged myocardial fibres is a result or, at the most, an accompanying symptom of necrosis production - should therefore be discarded.

  13. Low-dose dobutamine stress gated SPET for identification of viable myocardium: comparison with stress-rest perfusion SPET and PET

    International Nuclear Information System (INIS)

    Yoshinaga, Keiichiro; Tamaki, Nagara; Katoh, Chietsugu; Kuge, Yuji; Noriyasu, Kazuyuki; Yamada, Satoshi; Ito, Yoshinori; Kohya, Tetsuro; Kitabatake, Akira; Kawai, Yuko

    2002-01-01

    The detection of viable myocardium is important for the prediction of functional recovery after revascularisation. However, a fixed perfusion defect often includes viable myocardium, and perfusion imaging then underestimates myocardial viability. We previously reported that low-dose dobutamine stress gated single-photon emission tomography (SPET) provides similar findings to dobutamine stress echocardiography in the assessment of myocardial viability. The present study investigated whether low-dose dobutamine stress gated SPET is of additional value as compared with stress-rest technetium-99m tetrofosmin SPET for the detection of myocardial viability. Standard stress-rest perfusion SPET, low-dose dobutamine stress gated SPET and fluorine-18 fluorodeoxyglucose positron emission tomography (FDG PET) were studied in 23 patients (mean age 67±7.6 years) with previous myocardial infarction. Twenty-one of them were successfully studied with each technique. FDG PET viability (FDG uptake ≥50%) was employed as the gold standard. One-day stress-rest 99m Tc-tetrofosmin myocardial SPET was performed. After the resting study, gated SPET was acquired following infusion of 7.5 μg kg -1 min -1 of dobutamine. Left ventricular wall motion in 16 segments was assessed by cine mode display using a four-point scale. Myocardial viability was considered present when there was improvement by one point. Of a total of 336 segments analysed, 53 had persistent defects on stress-rest perfusion SPET. FDG viability was seen in 16 of 17 dobutamine-responsive segments, but in only 11 of 36 dobutamine non-responsive segments (P<0.01). Thus, in the segments with persistent defects, viability findings on low-dose dobutamine stress gated SPET were concordant with those on FDG PET in 77% of segments (kappa value =0.55). For the detection of FDG-viable myocardium, the combination of stress-rest perfusion SPET and low-dose dobutamine stress gated SPET achieved a better sensitivity than stress

  14. Improved identification of viable myocardium using second harmonic imaging during dobutamine stress echocardiography

    NARCIS (Netherlands)

    F. Sozzi (Fabiola); D. Poldermans (Don); J.J. Bax (Jeroen); A. Elhendy (Abdou); E.C. Vourvouri (Eleni); R. Valkema (Roelf); J. de Sutter; A.F.L. Schinkel (Arend); A. Borghetti; J.R.T.C. Roelandt (Jos)

    2001-01-01

    textabstractOBJECTIVE: To determine whether, compared with fundamental imaging, second harmonic imaging can improve the accuracy of dobutamine stress echocardiography for identifying viable myocardium, using nuclear imaging as a reference. PATIENTS: 30 patients with chronic left

  15. Mammalian DNA Repair. Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Wood, Richard D.

    2003-01-24

    The Gordon Research Conference (GRC) on Mammalian DNA Repair was held at Harbortown Resort, Ventura Beach, CA. Emphasis was placed on current unpublished research and discussion of the future target areas in this field.

  16. Pathological mechanism for delayed hyperenhancement of chronic scarred myocardium in contrast agent enhanced magnetic resonance imaging.

    Directory of Open Access Journals (Sweden)

    Jian Wang

    Full Text Available OBJECTIVES: To evaluate possible mechanism for delayed hyperenhancement of scarred myocardium by investigating the relationship of contrast agent (CA first pass and delayed enhancement patterns with histopathological changes. MATERIALS AND METHODS: Eighteen pigs underwent 4 weeks ligation of 1 or 2 diagonal coronary arteries to induce chronic infarction. The hearts were then removed and perfused in a Langendorff apparatus. The hearts firstly experienced phosphorus 31 MR spectroscopy. The hearts in group I (n = 9 and II (n = 9 then received the bolus injection of Gadolinium diethylenetriamine pentaacetic acid (0.05 mmol/kg and gadolinium-based macromolecular agent (P792, 15 µmol/kg, respectively. First pass T2* MRI was acquired using a gradient echo sequence. Delayed enhanced T1 MRI was acquired with an inversion recovery sequence. Masson's trichrome and anti- von Willebrand Factor (vWF staining were performed for infarct characterization. RESULTS: Wash-in of both kinds of CA caused the sharp and dramatic T2* signal decrease of scarred myocardium similar to that of normal myocardium. Myocardial blood flow and microvessel density were significantly recovered in 4-week-old scar tissue. Steady state distribution volume (ΔR1 relaxation rate of Gd-DTPA was markedly higher in scarred myocardium than in normal myocardium, whereas ΔR1 relaxation rate of P792 did not differ significantly between scarred and normal myocardium. The ratio of extracellular volume to the total water volume was significantly greater in scarred myocardium than in normal myocardium. Scarred myocardium contained massive residual capillaries and dilated vessels. Histological stains indicated the extensively discrete matrix deposition and lack of cellular structure in scarred myocardium. CONCLUSIONS: Collateral circulation formation and residual vessel effectively delivered CA into scarred myocardium. However, residual vessel without abnormal hyperpermeability allowed Gd

  17. Probing myocardium biomechanics using quantitative optical coherence elastography

    Science.gov (United States)

    Wang, Shang; Lopez, Andrew L.; Morikawa, Yuka; Tao, Ge; Li, Jiasong; Larina, Irina V.; Martin, James F.; Larin, Kirill V.

    2015-03-01

    We present a quantitative optical coherence elastographic method for noncontact assessment of the myocardium elasticity. The method is based on shear wave imaging optical coherence tomography (SWI-OCT), where a focused air-puff system is used to induce localized tissue deformation through a low-pressure short-duration air stream and a phase-sensitive OCT system is utilized to monitor the propagation of the induced tissue displacement with nanoscale sensitivity. The 1-D scanning of M-mode OCT imaging and the application of optical phase retrieval and mapping techniques enable the reconstruction and visualization of 2-D depth-resolved shear wave propagation in tissue with ultra-high frame rate. The feasibility of this method in quantitative elasticity measurement is demonstrated on tissue-mimicking phantoms with the estimated Young's modulus compared with uniaxial compression tests. We also performed pilot experiments on ex vivo mouse cardiac muscle tissues with normal and genetically altered cardiomyocytes. Our results indicate this noncontact quantitative optical coherence elastographic method can be a useful tool for the cardiac muscle research and studies.

  18. Reproducibility of P-31 spectroscopic imaging of normal human myocardium

    International Nuclear Information System (INIS)

    Tavares, N.J.; Chew, W.; Auffermann, W.; Higgins, C.B.

    1988-01-01

    To assess reproducibility of P-31 MR spectroscopy of human myocardium, ten normal male volunteers were studied on two separate occasions. Spectra were acquired on a clinical 1.5-T MR imaging unit (Signa, General Electric) using a one-dimensional gated spectroscopic imaging sequence (matrix size, 32 X 256) over 20 minutes. Peaks in the adenosine triphosphate (ATP) region, phosphocreatine (PCR), phosphodiesters (PD), and peaks attributable to 2,3 diphosphoglycerate from blood were observed. Interindividual and intraindividual variability expressed as standard errors of the mean (mean +- SEM) were 1.54 +- 0.04 (variability among subjects) and 0.04 (variability between first and second studies) for PCR/β ATP; 0.97 +- 0.18 and 0.06 for PD/β ATP; and 0.62 +- 0.10 and 0.05 for PD/PCR, respectively. In conclusion, P-31 MR spectroscopy yields consistent and reproducible myocardial spectra that might be useful in the future for the evaluation and monitoring of cardiac disease

  19. The myocardium functional reserve indicators in junior children with recurrent acute upper respiratory tract infection

    Directory of Open Access Journals (Sweden)

    L.S. Ovcharenko

    2017-02-01

    Full Text Available Background. The problem of early diagnosis of cardiovascular diseases in children is relevant throughout the world and in Ukraine, as in childhood the health and quality of life of an adult are formed. The psychoemotional stress in junior children as well as increasingly complicating school curriculum, information overload with electronic gadgets, increased frequency of colds in children cause physical inactivity. In addition, infectious agents have a toxic effect on the myocardium, altering its functional state. All these together adversely affect the formation and development of the cardiovascular and respiratory systems of children. The aim was to study the functional reserve of the myocardium in junior children, depending on the frequency of upper respiratory tract infection (URTI. Materials and methods. The study examined 1109 children aged 6 to 9 years old. The URTI incidence was analyzed depending on the age. In the study, the children were divided into two groups. Group 1 consisted of the children with URTI — 210. Group 2 involved the children with occasional URTI — 899. Results. Among 210 surveyed children with upper respiratory infections 171 schoolboys (81.4 % had reduced functional reserve of the myocardium, which is consistent with findings from other studies. In children aged 7 and 9 years old, the number of reduced functional reserve of the myocardium varies from 70 to 82 % in seven-year children, among the schoolboys aged 6 and 8 years old the incidence of reduced functional reserve of the myocardium increased from 83 to 100 % in six-year children. Conclusions. Children with URTI have a reduced functional reserve of the myocardium. Children with episodic URTI have higher rates of functional reserve of the myocardium, therefore reducing the incidence of URTI will lead to the improvement of the myocardium functional state.

  20. Perfusion single photon emission computed tomography of myocardium with 99mTc-tetra-phosmine (Myoview)

    International Nuclear Information System (INIS)

    Khusainova, Sh.K.; Zholdybaj, Zh.; Potapov, A.V.; Karaev, O.S.; Akhmetova, G.R.

    2003-01-01

    The aim of the work is study of diagnostic valuation of myocardium scintigraphy with help of the 99m Tc-tetrophosmin, Myoview in determination of latent coronary blood-circulation destabilization in liquidators of the Chernobyl accident (LChA) and persons living in the Semipalatinsk test site (STS) region. The perfusion myocardium scintigraphy was made to 71 patients (5 women and 66 men) from those - 33 LChA and 37 - residents of STS region. The examination was carried out in 'ADAC Genesys Epic' apparatus (USA). Mean age of the patients was 46.3±2.3 years old. In the result of examination the left ventricle myocardium perfusion reduction on 30 % and more was revealed. The distribution of radiopharmaceutical by the myocardium parts were relatively proportional both with pharmacologic load (ATF, dipiridamol) and the rest in 48 (67.7 %) patients. So, the 99m Tc-tetrophosmin, Myoview pharmaceutical allows with high rate estimate the myocardium perfusion and get a high qualitative images, that permits to identify localization, character and distribution of myocardium perfusion reduction in the revealed areas. In the result of myocardine scintigraphy with the pharmacologic load trial conducting the both the latent coronary blood-circulation destabilization forms and the incoming ones were differentiated

  1. Genetics Home Reference: arrhythmogenic right ventricular cardiomyopathy

    Science.gov (United States)

    ... cardiomyopathy Merck Manual Consumer Version: Cardiomyopathy Merck Manual Consumer Version: Overview of Abnormal Heart Rhythms Orphanet: Arrhythmogenic right ventricular cardiomyopathy Orphanet: Familial isolated arrhythmogenic right ventricular ...

  2. Factors related to outcome in heart failure with a preserved (or normal) left ventricular ejection fraction.

    Science.gov (United States)

    Sanderson, John E

    2016-07-01

    Heart failure with a preserved ejection faction (HFpEF) is a growing and expensive cause of heart failure (HF) affecting particularly the elderly. It differs in substantial ways in addition to the normal left ventricular ejection fraction, from the more easily recognized form of heart failure with a reduced ejection fraction (HFrEF or 'systolic heart failure') and unlike HFrEF there have been little advances in treatment. In part, this relates to the complexity of the pathophysiology and identifying the correct targets. In HFpEF, there appears to be widespread stiffening of the vasculature and the myocardium affecting ventricular function (both systolic and diastolic), impeding ventricular suction, and thus early diastolic filling leading to breathlessness on exertion and later atrial failure and fibrillation. Left ventricular ejection fraction tends to gradually decline and some evolve into HFrEF. Most patients also have a mixture of several co-morbidities including hypertension, diabetes, obesity, poor renal function, lack of fitness, and often poor social conditions. Therefore, many factors may influence outcome in an individual patient. In this review, the epidemiology, possible causation, pathophysiology, the influence of co-morbidities and some of the many potential predictors of outcome will be considered.

  3. Blockade of KCa3.1 Attenuates Left Ventricular Remodeling after Experimental Myocardial Infarction

    Directory of Open Access Journals (Sweden)

    Chen-Hui Ju

    2015-07-01

    Full Text Available Background/Aims: After myocardial infarction (MI, cardiac fibrosis greatly contributes to left ventricular remodeling and heart failure. The intermediate-conductance calcium-activated potassium Channel (KCa3.1 has been recently proposed as an attractive target of fibrosis. The present study aimed to detect the effects of KCa3.1 blockade on ventricular remodeling following MI and its potential mechanisms. Methods: Myocardial expression of KCa3.1 was initially measured in a mouse MI model by Western blot and real time-polymerase chain reaction. Then after treatment with TRAM-34, a highly selective KCa3.1 blocker, heart function and fibrosis were evaluated by echocardiography, histology and immunohistochemistry. Furthermore, the role of KCa3.1 in neonatal mouse cardiac fibroblasts (CFs stimulated by angiotensin II (Ang II was tested. Results: Myocardium expressed high level of KCa3.1 after MI. Pharmacological blockade of KCa3.1 channel improved heart function and reduced ventricular dilation and fibrosis. Besides, a lower prevalence of myofibroblasts was found in TRAM-34 treatment group. In vitro studies KCa3.1 was up regulated in CFs induced by Ang II and suppressed by its blocker.KCa3.1 pharmacological blockade attenuated CFs proliferation, differentiation and profibrogenic genes expression and may regulating through AKT and ERK1/2 pathways. Conclusion: Blockade of KCa3.1 is able to attenuate ventricular remodeling after MI through inhibiting the pro-fibrotic effects of CFs.

  4. Myocardial thallium-201 kinetics in normal and ischemic myocardium

    International Nuclear Information System (INIS)

    Grunwald, A.M.; Watson, D.D.; Holzgrefe, H.H. Jr.; Irving, J.F.; Beller, G.A.

    1981-01-01

    The net myocardial accumulation of thallium-201 after injection depends upon the net balance between continuing myocardial extraction from low levels of recirculating thallium in the blood compartment and the net rate of efflux of thallium from the myocardium into the extracardiac blood pool. These experiments were designed to measure separately the myocardial extraction and intrinsic myocardial efflux of thallium-201 at normal and at reduced rates of myocardial blood flow. The average myocardial extraction fraction at normal blood flow in 10 anesthetized dogs was 82 +/- 6% (+/- SD) at normal coronary arterial perfusion pressures and increased insignificantly, to 85 +/- 7%, at coronary perfusion pressures of 10--35 mm Hg. At normal coronary arterial perfusion pressures in 12 additional dogs, the intrinsic thallium washout in the absence of systemic recirculation had a half-time (T 1/2) of 54 +/- 7 minutes. The intrinsic cellular washout rate began to increase as distal perfusion pressures fell below 60 mm Hg and increased markedly to a T 1/2 of 300 minutes at perfusion pressures of 25--30 mm Hg. A second, more rapid component of intrinsic thallium washout (T 1/2 2.5 minutes) representing approximately 7% of the total initially extracted myocardial thallium was observed. The faster washout component is presumed to be due to washout of interstitial thallium unextracted by myocardial cells, whereas the slower component is presumed due to intracellular washout. The net clearance time of thallium measured after i.v. injection is much longer than the intrinsic myocardial cellular washout rate because of continuous replacement of myocardial thallium from systemic recirculation. Myocardial redistribution of thallium-201 in states of chronically reduced perfusion cannot be the result of increased myocardial extraction efficiency, but rather, is the result of the slower intrinsic cellular washout rate at reduced perfusion levels

  5. Noninvasive imaging of three-dimensional cardiac activation sequence during pacing and ventricular tachycardia.

    Science.gov (United States)

    Han, Chengzong; Pogwizd, Steven M; Killingsworth, Cheryl R; He, Bin

    2011-08-01

    Imaging cardiac excitation within ventricular myocardium is important in the treatment of cardiac arrhythmias and might help improve our understanding of arrhythmia mechanisms. This study sought to rigorously assess the imaging performance of a 3-dimensional (3D) cardiac electrical imaging (3DCEI) technique with the aid of 3D intracardiac mapping from up to 216 intramural sites during paced rhythm and norepinephrine (NE)-induced ventricular tachycardia (VT) in the rabbit heart. Body surface potentials and intramural bipolar electrical recordings were simultaneously measured in a closed-chest condition in 13 healthy rabbits. Single-site pacing and dual-site pacing were performed from ventricular walls and septum. VTs and premature ventricular complexes (PVCs) were induced by intravenous NE. Computed tomography images were obtained to construct geometry models. The noninvasively imaged activation sequence correlated well with invasively measured counterpart, with a correlation coefficient of 0.72 ± 0.04, and a relative error of 0.30 ± 0.02 averaged over 520 paced beats as well as 73 NE-induced PVCs and VT beats. All PVCs and VT beats initiated in the subendocardium by a nonreentrant mechanism. The averaged distance from the imaged site of initial activation to the pacing site or site of arrhythmias determined from intracardiac mapping was ∼5 mm. For dual-site pacing, the double origins were identified when they were located at contralateral sides of ventricles or at the lateral wall and the apex. 3DCEI can noninvasively delineate important features of focal or multifocal ventricular excitation. It offers the potential to aid in localizing the origins and imaging activation sequences of ventricular arrhythmias, and to provide noninvasive assessment of the underlying arrhythmia mechanisms. Copyright © 2011 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

  6. Characteristics of left ventricular hypertrophy estimated by MIBG and BMIPP cardiac scintigraphy in patients undergoing peritoneal dialysis

    Energy Technology Data Exchange (ETDEWEB)

    Ohashi, Hiroshige; Oda, Hiroshi; Ohno, Michiya; Watanabe, Sachirow; Kotoo, Yasunori; Matsuno, Yukihiko [Gifu Prefectural Hospital (Japan)

    2002-12-01

    Left ventricular hypertrophy (LVH) has been reported as a major factor in morbidity and mortality in chronic dialysis patients. However, cardiovascular mortality in peritoneal dialysis (PD) patients with LVH is substantially similar to that in hemodialysis (HD) patients. The present study sought to study whether sympathetic nerve activity and fatty acid metabolism of the myocardium estimated by {sup 123}I metaiodobenzylguanidine (MIBG) and {sup 123}I {beta}-methyl-p-iodophenyl-pentadecanoic acid (BMIPP) myocardial scintigraphy are impaired or not in PD patients with LVH. The underlying disease of 45 PD patients enrolled in this study was chronic glomerulonephritis in all cases. Serum levels of natriuretic peptides (arterial natriuretic peptide (ANP), brain natriuretic peptide (BNP)) and free carnitine and MIBG, BMIPP myocardial scintigraphy and 2-dimensional echocardiography were measured in these 45 PD patients. The following results were obtained. The prevalence of increased left ventricular mass index (LVMI) was 84.4%. LVMI correlated with age, and serum levels of ANP and BNP, and inversely correlated with a heart-to-mediastinum ratio (H/M) estimated by MIBG and BMIPP myocardial scintigraphy. Percentages of the normal image of MIBG and BMIPP measured with a single photon emission computed tomography (SPECT) were 37.8% and 62.2%, respectively. The PD patients showing the diffuse defect of MIBG or BMIPP imaging had the decrease in left ventricular ejection fraction (LVEF). Especially, the serum level of free carnitine was reduced in the PD patients with diffuse defect of BMIPP SPECT. From these results, we concluded that PD patients with LVH showed impaired sympathetic nerve activity and fatty acid metabolism of the myocardium. Metabolic and functional disturbances of the myocardium may influence mortality in PD patients. (author)

  7. Assessment of left ventricular function at different levels of exercise using gold-195m in asymptomatic diabetics

    International Nuclear Information System (INIS)

    Fazio, F.; Margonato, A.; Gerundini, P.; Vicedomini, G.; Gilardi, M.C.; Fregoso, A.; Bencivelli, W.; Milanesi, L.; Pozza, G.

    1985-01-01

    Left ventricular ejection fraction (LVEF) was evaluated by gold-195m first pass ventriculography in 10 diabetic patients with microangiopathy, in 10 diabetics without any complications, and in 10 healthy controls during maximum exercise. No differences among groups were present at rest, but at maximal exercise LVEF was significantly lower in microangiopathic patients than in the other two groups. Also muscle blood flow measured by xenon-133 washout was significantly lower during exercise in microangiopathic subjects. Small-vessel involvement of myocardium and muscle could play a role in the development of cardiovascular abnormalities during exercise in diabetics

  8. The management of ventricular dysrhythmia in aconite poisoning.

    Science.gov (United States)

    Coulson, James M; Caparrotta, Thomas M; Thompson, John P

    2017-06-01

    Aconite poisoning is relatively rare but is frequently complicated by ventricular dysrhythmias, which may be fatal. Molecular basis of aconite alkaloid ventricular arrhythmogenicity: Aconite exerts its toxic effects due to the presence of an admixture of alkaloids present in all parts of the plant. The major target of these aconite alkaloids is the fast voltage-gates sodium channel, where they cause persistent activation. This blockade of the channel in the activated state promotes automaticity within the ventricular myocardium and the generation of ventricular arrhythmias. Aconitine-induced arrhythmias: Aconite alkaloids are known to cause many different types of disturbance of heart rhythm. However, this focused review specifically looks at ventricular rhythm disturbances, namely ventricular ectopy, ventricular tachycardia, torsades des pointes and ventricular fibrillation. The objective of this review was to identify the outcome of anti-dysrhythmic strategies from animal studies and case reports in humans in order to guide the management of ventricular dysrhythmias in aconite poisoning in humans. A review of the literature in English was conducted in PubMed and Google Scholar from 1966 to July 2016 using the search terms "aconite/aconitine"; "aconite/aconitine + poisoning" and "aconite/aconitine + dysrhythmia". 168 human case-reports and case-series were identified by these searches, of which 103 were rejected if exposure to aconite did not result in ventricular dysrhythmias, if it was uncertain as to whether aconite had been ingested, if other agents were co-ingested, if there was insufficient information to determine the type of treatments administered or if there was insufficient information to determine outcome. Thus, 65 case reports of probable aconite poisoning that resulted in ventricular dysrhythmias were identified. Toxicokinetic data in aconite poisoning: Data were only available in three papers; the presence of ventricular rhythm disturbances

  9. Effect of myocardial viability in the infarct area on regional left ventricular function

    International Nuclear Information System (INIS)

    Ishii, Toshihiko; Watanabe, Takeshi; Usui, Mikio; Nagai, Yoshikazu

    1990-01-01

    This study explored the relationship between global left ventricular ejection fraction (LVEF), regional LVEF of infarct myocardium, and the viability of the myocardium due to the development of collaterals in the infarct area. Each was evaluated by exercise thallium-201 myocardial SPECT, multigated blood pool scintigraphy and coronary angiography. A total of 68 patients with old anteroseptal myocardial infarction and 23 normal persons were studied. The patients were found to have septal defect on exercise thallium images. According to the appearance of redistribution (RD) on delayed images, the patients were classified as having positive RD (n=42, 62%) or negative RD (n=26, 38%). The global LVEF was compared with regional LVEF of the basal, middle and apical areas within septum, as calculated by multigated blood pool scintigraphy. There was no significant difference in global LVEF between the groups of positive and negative RD patients. However, regional LVEF of the basal and middle areas was significantly larger in the group of positive RD than the group of negative RD. Collaterals were significantly observed in the group of positive RD, as compared with the group of negative RD (53% vs 25%). It was more frequent in cases of higher degree of stenosis. In the group of negative RD, none of the patients had collaterals when coronary stenosis was 90% or less. Redistribution may reflect myocardial viability. Myocardial viability within the infarct area had favorable influences on the regional left ventricular function. Therefore, not only global but also regional left ventricular function is necessary for better understanding of pathophysiology of myocardial infarction.(N.K.)

  10. Bioprinting 3D microfibrous scaffolds for engineering endothelialized myocardium and heart-on-a-chip

    Science.gov (United States)

    Zhang, Yu Shrike; Arneri, Andrea; Bersini, Simone; Shin, Su-Ryon; Zhu, Kai; Goli-Malekabadi, Zahra; Aleman, Julio; Colosi, Cristina; Busignani, Fabio; Dell'Erba, Valeria; Bishop, Colin; Shupe, Thomas; Demarchi, Danilo; Moretti, Matteo; Rasponi, Marco; Dokmeci, Mehmet Remzi; Atala, Anthony; Khademhosseini, Ali

    2016-01-01

    Engineering cardiac tissues and organ models remains a great challenge due to the hierarchical structure of the native myocardium. The need of integrating blood vessels brings additional complexity, limiting the available approaches that are suitable to produce integrated cardiovascular organoids. In this work we propose a novel hybrid strategy based on 3D bioprinting, to fabricate endothelialized myocardium. Enabled by the use of our composite bioink, endothelial cells directly bioprinted within microfibrous hydrogel scaffolds gradually migrated towards the peripheries of the microfibers to form a layer of confluent endothelium. Together with controlled anisotropy, this 3D endothelial bed was then seeded with cardiomyocytes to generate aligned myocardium capable of spontaneous and synchronous contraction. We further embedded the organoids into a specially designed microfluidic perfusion bioreactor to complete the endothelialized-myocardium-on-a-chip platform for cardiovascular toxicity evaluation. Finally, we demonstrated that such a technique could be translated to human cardiomyocytes derived from induced pluripotent stem cells to construct endothelialized human myocardium. We believe that our method for generation of endothelialized organoids fabricated through an innovative 3D bioprinting technology may find widespread applications in regenerative medicine, drug screening, and potentially disease modeling. PMID:27710832

  11. Bioprinting 3D microfibrous scaffolds for engineering endothelialized myocardium and heart-on-a-chip.

    Science.gov (United States)

    Zhang, Yu Shrike; Arneri, Andrea; Bersini, Simone; Shin, Su-Ryon; Zhu, Kai; Goli-Malekabadi, Zahra; Aleman, Julio; Colosi, Cristina; Busignani, Fabio; Dell'Erba, Valeria; Bishop, Colin; Shupe, Thomas; Demarchi, Danilo; Moretti, Matteo; Rasponi, Marco; Dokmeci, Mehmet Remzi; Atala, Anthony; Khademhosseini, Ali

    2016-12-01

    Engineering cardiac tissues and organ models remains a great challenge due to the hierarchical structure of the native myocardium. The need of integrating blood vessels brings additional complexity, limiting the available approaches that are suitable to produce integrated cardiovascular organoids. In this work we propose a novel hybrid strategy based on 3D bioprinting, to fabricate endothelialized myocardium. Enabled by the use of our composite bioink, endothelial cells directly bioprinted within microfibrous hydrogel scaffolds gradually migrated towards the peripheries of the microfibers to form a layer of confluent endothelium. Together with controlled anisotropy, this 3D endothelial bed was then seeded with cardiomyocytes to generate aligned myocardium capable of spontaneous and synchronous contraction. We further embedded the organoids into a specially designed microfluidic perfusion bioreactor to complete the endothelialized-myocardium-on-a-chip platform for cardiovascular toxicity evaluation. Finally, we demonstrated that such a technique could be translated to human cardiomyocytes derived from induced pluripotent stem cells to construct endothelialized human myocardium. We believe that our method for generation of endothelialized organoids fabricated through an innovative 3D bioprinting technology may find widespread applications in regenerative medicine, drug screening, and potentially disease modeling. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Measurement of ventricular function using Doppler ultrasound

    International Nuclear Information System (INIS)

    Teague, S.M.

    1986-01-01

    Doppler has wide application in the evaluation of valvular heart disease. The need to know ventricular function is a much more common reason for an echocardiographic evaluation. Interestingly, Doppler examinations can assess ventricular function from many perspectives. Description of ventricular function entails measurement of the timing, rate and volume of ventricular filling and ejection. Doppler ultrasound examination reveals all of these aspects of ventricular function noninvasively, simply, and without great expense or radiation exposure, as described in this chapter

  13. Idiopathic ventricular tachycardia and fibrillation.

    Science.gov (United States)

    Belhassen, B; Viskin, S

    1993-06-01

    Important data have recently been added to our understanding of sustained ventricular tachyarrhythmias occurring in the absence of demonstrable heart disease. Idiopathic ventricular tachycardia (VT) is usually of monomorphic configuration and can be classified according to its site of origin as either right monomorphic (70% of all idiopathic VTs) or left monomorphic VT. Several physiopathological types of monomorphic VT can be presently individualized, according to their mode of presentation, their relationship to adrenergic stress, or their response to various drugs. The long-term prognosis is usually good. Idiopathic polymorphic VT is a much rarer type of arrhythmia with a less favorable prognosis. Idiopathic ventricular fibrillation may represent an underestimated cause of sudden cardiac death in ostensibly healty patients. A high incidence of inducibility of sustained polymorphic VT with programmed ventricular stimulation has been found by our group, but not by others. Long-term prognosis on Class IA antiarrhythmic medications that are highly effective at electrophysiologic study appears excellent.

  14. Left ventricular apical ballooning syndrome

    International Nuclear Information System (INIS)

    Rahman, N.; Tai, J.; Soofi, A.

    2007-01-01

    The transient left ventricular apical ballooning syndrome, also known as Takotsubo cardiomyopathy, is characterized by transient left ventricular dysfunction in the absence of obstructive epicardial coronary disease. Although the syndrome has been reported in Japan since 1990, it is rare in other regions. Rapid recognition of the syndrome can modify the diagnostic and therapeutic attitude i.e. avoiding thrombolysis and performing catheterization in the acute phase. (author)

  15. The shape of mammalian phylogeny

    DEFF Research Database (Denmark)

    Purvis, Andy; Fritz, Susanne A; Rodríguez, Jesús

    2011-01-01

    an assemblage, ecoregion or larger area always tends to be more unbalanced than expected from the phylogeny of species at the next more inclusive spatial scale. We conclude with a verbal model of mammalian macroevolution, which emphasizes the importance to diversification of accessing new regions...

  16. Evolutionary dynamics of mammalian karyotypes

    Directory of Open Access Journals (Sweden)

    Carlo Alberto Redi

    2012-12-01

    Full Text Available This special volume of Cytogenetic and Genome Research (edited by Roscoe Stanyon, University of Florence and Alexander Graphodatsky, Siberian division of the Russian Academy of Sciences is dedicated to the fascinating long search of the forces behind the evolutionary dynamics of mammalian karyotypes, revealed after the hypotonic miracle of the 1950s....

  17. Technology of mammalian cell encapsulation

    NARCIS (Netherlands)

    Uludag, H; De Vos, P; Tresco, PA

    2000-01-01

    Entrapment of mammalian cells in physical membranes has been practiced since the early 1950s when it was originally introduced as a basic research tool. The method has since been developed based on the promise of its therapeutic usefulness in tissue transplantation. Encapsulation physically isolates

  18. Ventricular arrhythmias in Chagas disease

    Directory of Open Access Journals (Sweden)

    Marco Paulo Tomaz Barbosa

    2015-02-01

    Full Text Available Sudden death is one of the most characteristic phenomena of Chagas disease, and approximately one-third of infected patients develop life-threatening heart disease, including malignant ventricular arrhythmias. Fibrotic lesions secondary to chronic cardiomyopathy produce arrhythmogenic substrates that lead to the appearance and maintenance of ventricular arrhythmias. The objective of this study is to discuss the main clinical and epidemiological aspects of ventricular arrhythmias in Chagas disease, the specific workups and treatments for these abnormalities, and the breakthroughs needed to determine a more effective approach to these arrhythmias. A literature review was performed via a search of the PubMed database from 1965 to May 31, 2014 for studies of patients with Chagas disease. Clinical management of patients with chronic Chagas disease begins with proper clinical stratification and the identification of individuals at a higher risk of sudden cardiac death. Once a patient develops malignant ventricular arrhythmia, the therapeutic approach aims to prevent the recurrence of arrhythmias and sudden cardiac death by the use of implantable cardioverter defibrillators, antiarrhythmic drugs, or both. In select cases, invasive ablation of the reentrant circuit causing tachycardia may be useful. Ventricular arrhythmias are important manifestations of Chagas cardiomyopathy. This review highlights the absence of high-quality evidence regarding the treatment of ventricular arrhythmias in Chagas disease. Recognizing high-risk patients who require specific therapies, especially invasive procedures such as the implantation of cardioverter defibrillators and ablative approaches, is a major challenge in clinical practice.

  19. A patient with type I CD36 deficiency whose myocardium accumulated 123I-BMIPP after 4 years.

    Science.gov (United States)

    Ito, K; Sugihara, H; Tanabe, T; Zen, K; Hikosaka, T; Adachi, Y; Katoh, S; Azuma, A; Nakagawa, M

    2001-06-01

    A 73-year-old man with aortic regurgitation was examined by 123I-alpha-methyl-p-iodophenylpentadecanoic acid (BMIPP) myocardial single photon emission computed tomography (SPECT) in 1995. Myocardial accumulation was not evident on either the early or the delayed image obtained 15 minutes and 3 hours, respectively, after injecting 123I-BMIPP. Flow cytometric analysis of CD36 expression in monocytes and platelets identified a type I CD36 deficiency. The patient was hospitalized for severe heart failure in 1999. Upon admission, the cardiothoracic ratio on chest X-rays was 73%, and the left ventricular end-diastolic diameter on echocardiograms was enlarged to 77 mm. On the second day, we performed 123I-BMIPP myocardial SPECT. Myocardial accumulation was evident in the delayed, but not in the early image. We repeated 123I-BMIPP myocardial SPECT on the 10th day after admission. Myocardial accumulation was evident on both early and delayed images. 99mTc-tetrofosmin myocardial SPECT was immediately performed after 123I-BMIPP myocardial SPECT to distinguish myocardial from pooling images in the left ventricle, but, because the images from both 99Tc-tetrofosmin and 123I-BMIPP myocardial SPECT were idential, we considered that the 123I-BMIPP myocardial SPECT images reflected the actual myocardial condition. The CD36 molecule transports long-chain fatty acid (LCFA) on the myocardial membrane, but 123I-BMIPP scintigraphy does not show any myocardial accumulation in patients with type I CD36 deficiency, indicating that myocardial LCFA uptake occurs through CD36 on the human myocardial membrane. Even though our patient had type I CD36 deficiency, BMIPP was uptaken by the myocardium during heart failure, suggesting a variant pathway on the human myocardial membrane for LCFA uptake.

  20. Pathophysiology and diagnosis of hibernating myocardium in patients with post-ischemic heart failure. The contribution of PET

    International Nuclear Information System (INIS)

    Camici, P.G.; Rimoldi, O.E.

    2003-01-01

    Identification and treatment of hibernating myocardium (HM) lead to improvement in left ventricular (LV) function and prognosis in patients with post-ischemic heart failure. Different techniques are used to diagnose HM: echocardiography, MRI, SPECT and PET and, in patients with moderate LV impairment, their predictive values are similar. There are few data on patients with severe LV dysfunction and heart failure in whom the greatest benefits are apparent after revascularization. Quantification of FDG uptake with PET during hyperinsulinemic euglycemic clamp is accurate in these patients with the greatest mortality risk in whom other techniques may give high false negative rates. The debate on whether resting myocardial blood flow to HM is reduced or not has stimulated new research on heart failure in patients with coronary artery disease. PET with H 2 15 O or 13 NH 3 has been used for the absolute quantification of regional blood flow in human HM. When HM is properly identified, resting blood flow is not different from that in healthy volunteers although a reduction of ∼20% can be demonstrated in a minority of cases. PET studies have shown that the main feature of HM is a severe impairment of coronary vasodilator reserve that improves after revascularization in parallel with LV function. Thus, the pathophysiology of HM is more complex than initially postulated. The recent evidence that repetitive ischemia in patients can be cumulative and lead to more severe and prolonged stunning, lends further support to the hypothesis that, at least initially, stunning and HM are two facets of the same coin. (author)

  1. The overloaded right heart and ventricular interdependence.

    Science.gov (United States)

    Naeije, Robert; Badagliacca, Roberto

    2017-10-01

    The right and the left ventricle are interdependent as both structures are nested within the pericardium, have the septum in common and are encircled with common myocardial fibres. Therefore, right ventricular volume or pressure overloading affects left ventricular function, and this in turn may affect the right ventricle. In normal subjects at rest, right ventricular function has negligible interaction with left ventricular function. However, the right ventricle contributes significantly to the normal cardiac output response to exercise. In patients with right ventricular volume overload without pulmonary hypertension, left ventricular diastolic compliance is decreased and ejection fraction depressed but without intrinsic alteration in contractility. In patients with right ventricular pressure overload, left ventricular compliance is decreased with initial preservation of left ventricular ejection fraction, but with eventual left ventricular atrophic remodelling and altered systolic function. Breathing affects ventricular interdependence, in healthy subjects during exercise and in patients with lung diseases and altered respiratory system mechanics. Inspiration increases right ventricular volumes and decreases left ventricular volumes. Expiration decreases both right and left ventricular volumes. The presence of an intact pericardium enhances ventricular diastolic interdependence but has negligible effect on ventricular systolic interdependence. On the other hand, systolic interdependence is enhanced by a stiff right ventricular free wall, and decreased by a stiff septum. Recent imaging studies have shown that both diastolic and systolic ventricular interactions are negatively affected by right ventricular regional inhomogeneity and prolongation of contraction, which occur along with an increase in pulmonary artery pressure. The clinical relevance of these observations is being explored. Published on behalf of the European Society of Cardiology. All rights

  2. Sestrin2 protects the myocardium against radiation-induced damage

    International Nuclear Information System (INIS)

    Zeng, Yue-Can; Chi, Feng; Xing, Rui; Gao, Song; Chen, Jia-Jia; Duan, Qiong-Yu; Sun, Yu-Nan; Niu, Nan; Tang, Mei-Yue; Wu, Rong; Zeng, Jing; Wang, Hong-Mei

    2016-01-01

    The purpose of this study was to investigate the role of Sestrin2 in response to radiation-induced injury to the heart and on the cardiomyopathy development in the mouse. Mice with genetic deletion of the Sestrin2 (Sestrin2 knockout mice [Sestrin2 KO]) and treatment with irradiation (22 or 15 Gy) were used as independent approaches to determine the role of Sestrin2. Echocardiography (before and after isoproterenol challenge) and left ventricular (LV) catheterization were performed to evaluate changes in LV dimensions and function. Masson's trichrome was used to assess myocardial fibrosis. Immunohistochemistry and Western blot were used to detect the capillary density. After 22 or 15 Gy irradiation, the LV ejection fraction (EF) was impaired in wt mice at 1 week and 4 months after irradiation when compared with sham irradiation. Compared to wt mice, Sestrin2 KO mice had significant reduction in reduced LVEF at 1 week and 4 months after irradiation. A significant increase in LV end-diastolic pressure and myocardial fibrosis and a significant decrease in capillary density were observed in irradiation-wt mice, as well as in irradiation-Sestrin2 KO mice. Sestrin2 involved in the regulation of cardiomyopathy (such as myocardial fibrosis) after irradiation. Overexpression of Sestrin2 might be useful in limiting radiation-induced myocardial injury. (orig.)

  3. Sestrin2 protects the myocardium against radiation-induced damage

    Energy Technology Data Exchange (ETDEWEB)

    Zeng, Yue-Can; Chi, Feng; Xing, Rui; Gao, Song; Chen, Jia-Jia; Duan, Qiong-Yu; Sun, Yu-Nan; Niu, Nan; Tang, Mei-Yue; Wu, Rong [Shengjing Hospital of China Medical University, Department of Medical Oncology, Cancer Center, Shenyang (China); Zeng, Jing [University of Washington School of Medicine, Department of Radiation Oncology, Seattle, WA (United States); Wang, Hong-Mei [Nanfang Hospital of Southern Medical University, Department of Radiation Oncology, Guangzhou (China)

    2016-05-15

    The purpose of this study was to investigate the role of Sestrin2 in response to radiation-induced injury to the heart and on the cardiomyopathy development in the mouse. Mice with genetic deletion of the Sestrin2 (Sestrin2 knockout mice [Sestrin2 KO]) and treatment with irradiation (22 or 15 Gy) were used as independent approaches to determine the role of Sestrin2. Echocardiography (before and after isoproterenol challenge) and left ventricular (LV) catheterization were performed to evaluate changes in LV dimensions and function. Masson's trichrome was used to assess myocardial fibrosis. Immunohistochemistry and Western blot were used to detect the capillary density. After 22 or 15 Gy irradiation, the LV ejection fraction (EF) was impaired in wt mice at 1 week and 4 months after irradiation when compared with sham irradiation. Compared to wt mice, Sestrin2 KO mice had significant reduction in reduced LVEF at 1 week and 4 months after irradiation. A significant increase in LV end-diastolic pressure and myocardial fibrosis and a significant decrease in capillary density were observed in irradiation-wt mice, as well as in irradiation-Sestrin2 KO mice. Sestrin2 involved in the regulation of cardiomyopathy (such as myocardial fibrosis) after irradiation. Overexpression of Sestrin2 might be useful in limiting radiation-induced myocardial injury. (orig.)

  4. The kinetics of {beta}-methyl-substituted labelled fatty acids in ischaemic myocardium: an analysis in man and with a blood-perfused isolated heart model

    Energy Technology Data Exchange (ETDEWEB)

    Marie, P.Y.; Ayalew, A.; Hassan, N.; Olivier, P.; Karcher, G.; Bertrand, A. [Dept. of Nuclear Medicine, UPRES EA, Nancy (France); Menu, P. [Dept. of Hematology and Physiology, University Henri Poincare, Nancy (France); Angioi, M.; Mertes, P.M.; Danchin, N. [Dept. of Cardiology, UPRES EA, Nancy (France); Fagret, D. [Dept. of Nuclear Medicine, Grenoble (France); Pasqualini, R. [CIS Bio International, Gif-sur-Yvette (France)

    1999-05-01

    {beta}-Methyl-substituted free fatty acids (FFAs) have been developed for myocardial single-photon emission tomography (SPET) imaging, but little is known about their kinetics in ischaemic conditions. The aim of this study was to determine the changes in the myocardial kinetics of a {beta}-methyl-branched FFA, [{sup 123}I]16-iodo-3-methyl-hexadecanoic acid (MIHA), under ischaemic conditions. The kinetics of MIHA were analysed: (a) using a blood-perfused isolated heart model subjected to moderate ischaemia (50% flow reduction) and (b) in patients who had an exercise thallium-201 SPET defect corresponding to either necrotic (n = 13) or chronically ischaemic and viable (n = 15) myocardium, and who underwent two consecutive SPET studies after MIHA injection. In animals, the myocardial early retention fraction of MIHA, but not its clearance rate, was dependent on coronary flow, the early retention fraction being higher in ischaemic than in normoxic conditions (0.24{+-}0.10 vs 0.14{+-}0.04, P = 0.004). In the patient SPET studies, the uptake of MIHA calculated in ischaemic and viable areas (G1: 74%{+-}9% of maximal left ventricular value) was different from that calculated in necrotic (G2: 59%{+-}7%, P<0.001) or normal (G3: 88{+-}6%, P<0.001) areas. By contrast, MIHA-clearance calculated between the two consecutive SPET studies was not different in G1, G2 and G3. Unlike in the case of other FFAs, the myocardial clearance of MIHA is not decreased by ischaemia. However, the early retention of MIHA is increased in the case of a moderate reduction in coronary flow, a property which might help in the detection of viability in chronically ischaemic myocardium. (orig.) With 5 figs., 3 tabs., 44 refs.

  5. Demonstration of disturbed free fatty acid metabolism of myocardium in patients with non-insulin-dependent diabetes mellitus as measured with iodine-123-heptadecanoic acid

    International Nuclear Information System (INIS)

    Kuikka, J.T.; Mustonen, J.N.; Uusitupa, M.I.J.; Rautio, P.; Vanninen, E.; Laakso, M.; Laensimies, E.; Kuopio Central Hospital

    1991-01-01

    Myocardial free fatty acid metabolism and left ventricular function were evaluated in 15 middle-aged patients with non-insulin dependent diabetes mellitus (NIDDM) and in 8 healthy control subjects. The study subjects had no evidence of coronary heart disease on the basis of clinical history, exercise ECG or myocardial perfusion scintigraphy. During peak exercise, iodine-123 hepatadecanoic acid (HDA) was intravenously injected. Myocardial activity distribution of 123 I-HDA was measured 10, 30, and 50 min after exercise using single-photon emission tomography (SPET); and then further corrected by free 123 I-iodine. Venous blood samples were drawn for detecting the plasma activity of 123 I. The net extraction of 123 I-HDA into the myocardium was obtained by dividing the corrected tissue 123 I concentration by the integral of the plasma time activity curve. The net extraction was 0.40±0.06 min -1 (mean±SD) patients with NIDDM and 0.38±0.006 min -1 in control subjects (P>0.1), respectively. The faster elimination rate of 123 I-HDA was found in patients with NIDDM (0.029±0.008 min -1 ) than in control subjects (0.022±0.004 min - 1); P 123 I-HDA and the change of LVEF, as well as with exercise load (r=0.68; P<0.01). In conclusion, evidence of an increased fatty acid utilization and triglyceride synthesis rate was observed in the diabetic myocardium. (orig.)

  6. Cine MR imaging assessment of regional left ventricular systolic wall thickening in patients with remote myocardial infarction

    International Nuclear Information System (INIS)

    Pfugfelder, P.; White, R.D.; Sechtem, U.; Gould, R.G.; Higgins, C.B.

    1986-01-01

    Cine MR imaging, a new rapid imaging technique, was used to acquire transverse images of the heart at a rate of 16-30 frames per cardiac cycle. Left ventricular wall thickness was measured at end diastole and end systole in six regions in the midventricular section of 13 healthy subjects and seven patients with previously documented myocardial infarction. Mean percent systolic wall thickening (%SWT) was 51% +- 26% in healthy subjects. In patients, %SWT was -8% +- 22% in the infarct zone and 42% +- 22% in the normal myocardium. In addition to the qualitative information derived from the cinematic display, determination of regional %SWT by cine-MR imaging may be useful for quantifying regional left ventricular dysfunction

  7. Free Radical Oxidation in Rat Myocardium after Maximum Permissible Hepatic Resection.

    Science.gov (United States)

    Ermolaev, P A; Khramykh, T P; Barskaya, L O

    2016-03-01

    Free radical oxidation in rat myocardial homogenate was studied by chemiluminescent assay during the early terms after maximum permissible liver resection. During this period, activation of free radical oxidation was biphasic. The critical terms characterized by dramatic intensification of free radical oxidation in the myocardium are the first hour and the first day after surgery. The period from 3 to 12 h after surgery, in which the indices of chemiluminescence decrease, can be tentatively termed as the period of "putative wellbeing". Normalization of the free radical oxidation processes in the myocardium occurred by day 7 after surgery.

  8. Statistical and fractal analysis of autofluorescent myocardium images in posthumous diagnostics of acute coronary insufficiency

    Science.gov (United States)

    Boichuk, T. M.; Bachinskiy, V. T.; Vanchuliak, O. Ya.; Minzer, O. P.; Garazdiuk, M.; Motrich, A. V.

    2014-08-01

    This research presents the results of investigation of laser polarization fluorescence of biological layers (histological sections of the myocardium). The polarized structure of autofluorescence imaging layers of biological tissues was detected and investigated. Proposed the model of describing the formation of polarization inhomogeneous of autofluorescence imaging biological optically anisotropic layers. On this basis, analytically and experimentally tested to justify the method of laser polarimetry autofluorescent. Analyzed the effectiveness of this method in the postmortem diagnosis of infarction. The objective criteria (statistical moments) of differentiation of autofluorescent images of histological sections myocardium were defined. The operational characteristics (sensitivity, specificity, accuracy) of these technique were determined.

  9. Mechanism-specific effects of adenosine on ventricular tachycardia.

    Science.gov (United States)

    Lerman, Bruce B; Ip, James E; Shah, Bindi K; Thomas, George; Liu, Christopher F; Ciaccio, Edward J; Wit, Andrew L; Cheung, Jim W; Markowitz, Steven M

    2014-12-01

    There is no universally accepted method by which to diagnose clinical ventricular tachycardia (VT) due to cAMP-mediated triggered activity. Based on cellular and clinical data, adenosine termination of VT is thought to be consistent with a diagnosis of triggered activity. However, a major gap in evidence mitigates the validity of this proposal, namely, defining the specificity of adenosine response in well-delineated reentrant VT circuits. To this end, we systematically studied the effects of adenosine in a model of canine reentrant VT and in human reentrant VT, confirmed by 3-dimensional, pace- and substrate mapping. Adenosine (12 mg [IQR 12-24]) failed to terminate VT in 31 of 31 patients with reentrant VT due to structural heart disease, and had no effect on VT cycle length (age, 67 years [IQR 53-74]); ejection fraction, 35% [IQR 20-55]). In contrast, adenosine terminated VT in 45 of 50 (90%) patients with sustained focal right or left outflow tract tachycardia. The sensitivity of adenosine for identifying VT due to triggered activity was 90% (95% CI, 0.78-0.97) and its specificity was 100% (95% CI, 0.89-1.0). Additionally, reentrant circuits were mapped in the epicardial border zone of 4-day-old infarcts in mongrel dogs. Adenosine (300-400 μg/kg) did not terminate sustained VT or have any effect on VT cycle length. These data support the concept that adenosine's effects on ventricular myocardium are mechanism specific, such that termination of VT in response to adenosine is diagnostic of cAMP-mediated triggered activity. © 2014 Wiley Periodicals, Inc.

  10. Correlation of Ventricular Arrhythmogenesis with Neuronal Remodeling of Cardiac Postganglionic Parasympathetic Neurons in the Late Stage of Heart Failure after Myocardial Infarction.

    Science.gov (United States)

    Zhang, Dongze; Tu, Huiyin; Wang, Chaojun; Cao, Liang; Muelleman, Robert L; Wadman, Michael C; Li, Yu-Long

    2017-01-01

    Introduction: Ventricular arrhythmia is a major cause of sudden cardiac death in patients with chronic heart failure (CHF). Our recent study demonstrates that N-type Ca 2+ currents in intracardiac ganglionic neurons are reduced in the late stage of CHF rats. Rat intracardiac ganglia are divided into the atrioventricular ganglion (AVG) and sinoatrial ganglion. Only AVG nerve terminals innervate the ventricular myocardium. In this study, we tested the correlation of electrical remodeling in AVG neurons with ventricular arrhythmogenesis in CHF rats. Methods and Results: CHF was induced in male Sprague-Dawley rats by surgical ligation of the left coronary artery. The data from 24-h continuous radiotelemetry ECG recording in conscious rats showed that ventricular tachycardia/fibrillation (VT/VF) occurred in 3 and 14-week CHF rats but not 8-week CHF rats. Additionally, as an index for vagal control of ventricular function, changes of left ventricular systolic pressure (LVSP) and the maximum rate of left ventricular pressure rise (LV dP/dt max ) in response to vagal efferent nerve stimulation were blunted in 14-week CHF rats but not 3 or 8-week CHF rats. Results from whole-cell patch clamp recording demonstrated that N-type Ca 2+ currents in AVG neurons began to decrease in 8-week CHF rats, and that there was also a significant decrease in 14-week CHF rats. Correlation analysis revealed that N-type Ca 2+ currents in AVG neurons negatively correlated with the cumulative duration of VT/VF in 14-week CHF rats, whereas there was no correlation between N-type Ca 2+ currents in AVG neurons and the cumulative duration of VT/VF in 3-week CHF. Conclusion: Malignant ventricular arrhythmias mainly occur in the early and late stages of CHF. Electrical remodeling of AVG neurons highly correlates with the occurrence of ventricular arrhythmias in the late stage of CHF.

  11. Left ventricular hypertrophy in valvular aortic stenosis: mechanisms and clinical implications.

    Science.gov (United States)

    Rader, Florian; Sachdev, Esha; Arsanjani, Reza; Siegel, Robert J

    2015-04-01

    Valvular aortic stenosis is the second most prevalent adult valve disease in the United States and causes progressive pressure overload, invariably leading to life-threatening complications. Surgical aortic valve replacement and, more recently, transcatheter aortic valve replacement effectively relieve the hemodynamic burden and improve the symptoms and survival of affected individuals. However, according to current American College of Cardiology/American Heart Association guidelines on the management of valvular heart disease, the indications for aortic valve replacement, including transcatheter aortic valve replacement, are based primarily on the development of clinical symptoms, because their presence indicates a dismal prognosis. Left ventricular hypertrophy develops in a sizeable proportion of patients before the onset of symptoms, and a growing body of literature demonstrates that regression of left ventricular hypertrophy resulting from aortic stenosis is incomplete after aortic valve replacement and associated with adverse early postoperative outcomes and worse long-term outcomes. Thus, reliance on the development of symptoms alone without consideration of structural abnormalities of the myocardium for optimal timing of aortic valve replacement potentially constitutes a missed opportunity to prevent postoperative morbidity and mortality from severe aortic stenosis, especially in the face of the quickly expanding indications of lower-risk transcatheter aortic valve replacement. The purpose of this review is to discuss the mechanisms and clinical implications of left ventricular hypertrophy in severe valvular aortic stenosis, which may eventually move to center stage as an indication for aortic valve replacement in the asymptomatic patient. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Bioenergetics of mammalian sperm capacitation.

    Science.gov (United States)

    Ferramosca, Alessandra; Zara, Vincenzo

    2014-01-01

    After ejaculation, the mammalian male gamete must undergo the capacitation process, which is a prerequisite for egg fertilization. The bioenergetics of sperm capacitation is poorly understood despite its fundamental role in sustaining the biochemical and molecular events occurring during gamete activation. Glycolysis and mitochondrial oxidative phosphorylation (OXPHOS) are the two major metabolic pathways producing ATP which is the primary source of energy for spermatozoa. Since recent data suggest that spermatozoa have the ability to use different metabolic substrates, the main aim of this work is to present a broad overview of the current knowledge on the energy-producing metabolic pathways operating inside sperm mitochondria during capacitation in different mammalian species. Metabolism of glucose and of other energetic substrates, such as pyruvate, lactate, and citrate, is critically analyzed. Such knowledge, besides its obvious importance for basic science, could eventually translate into the development of novel strategies for treatment of male infertility, artificial reproduction, and sperm selection methods.

  13. Review of the emerging role of optical polarimetry in characterization of pathological myocardium.

    Science.gov (United States)

    Ahmad, Iftikhar

    2017-10-01

    Myocardial infarction (MI), a cause of significant morbidity and mortality, is typically followed by microstructural alterations where the necrotic myocardium is steadily replaced with a collagen scar. Engineered remodeling of the fibrotic scar via stem cell regeneration has been shown to improve/restore the myocardium function after MI. Nevertheless, the heterogeneous nature of the scar patch may impair the myocardial electrical integrity, leading to the formation of arrhythmogenesis. Radiofrequency ablation (RFA) offers an effective treatment for focal arrhythmias where local heating generated via electric current at specific spots in the myocardium ablate the arrhythmogenic foci. Characterization of these myocardial pathologies (i.e., infarcted, stem cell regenerated, and RFA-ablated myocardial tissues) is of potential clinical importance. Optical polarimetry, the use of light to map and characterize the polarization signatures of a sample, has emerged as a powerful imaging tool for structural characterization of myocardial tissues, exploiting the underlying highly fibrous tissue nature. This study aims to review the recent progress in optical polarimetry pertaining to the characterization of myocardial pathologies while describing the underlying biological rationales that give rise to the optical imaging contrast in various pathologies of the myocardium. Future possibilities of and challenges to optical polarimetry in cardiac imaging clinics are also discussed. (2017) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE).

  14. Pitx2 confers left morphological, molecular, and functional identity to the sinus venosus myocardium

    Czech Academy of Sciences Publication Activity Database

    Ammirabile, G.; Tessari, A.; Pignataro, V.; Szumska, D.; Sardo, F.S.; Beneš Jr., Jiří; Balistreri, M.; Bhattacharya, S.; Sedmera, David; Campione, M.

    2012-01-01

    Roč. 93, č. 2 (2012), s. 291-301 ISSN 0008-6363 R&D Projects: GA ČR(CZ) GA304/08/0615 Institutional research plan: CEZ:AV0Z50110509 Keywords : Pitx2 * sinus venosus myocardium * optical mapping * mouse cardiac development Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery Impact factor: 5.940, year: 2012

  15. Preliminary applied study of assessment ischemic/viable myocardium by 99Tcm-HL91

    International Nuclear Information System (INIS)

    Liu Gang; Wu Hua

    2004-01-01

    Objective: To investigate the representation of 99 Tc m -HL91 in the ischemic myocardium, evaluate the diagnosis value of 99 Tc m -HL91 on hypoxic but viable myocardium. Methods: Six patients with cardiac infarction all underwent 99 Tc m -MIBI SPECT and 99 Tc m -HL91 SPECT. Average radioactivity of ischemic area and normal area were respectively obtained by ROI (2 x 2 pixels) on heart minor axis of images, And the radioactivity ratios of target (ischemic area)-to-non target(normal area)were calculated. Results: In image of 99 Tc m -HL91 SPECT, two patients who's radioactivity coloboma of 99 Tc m -MIBI image could be filled with 99 Tc m -HL91, four patients were not caught sight of obvious filling up. Conclusion 99 Tc m -HL91 can be selectively uptaken by ischemic and hypoxic but viable myocardium. it combination of 99 Tc m -MIBI SPECT may be good for accurate diagnosis and differentiation of viable myocardium. (authors)

  16. Synchronous In Situ ATPase Activity, Mechanics, and Ca2+ Sensitivity of Human and Porcine Myocardium

    Czech Academy of Sciences Publication Activity Database

    Griffiths, P. J.; Isackson, H.; Pelc, Radek; Redwood, C.S.; Funari, S.S.; Watkins, H.; Ashley, C. C.

    2009-01-01

    Roč. 97, č. 9 (2009), s. 2503-2512 ISSN 0006-3495 R&D Projects: GA MŠk(CZ) LC06063 Grant - others:EC(XE) RII3-CT-2004-506008 Institutional research plan: CEZ:AV0Z50110509 Keywords : myocardium * actomyosin- ATPase * synchrotron-radiation Subject RIV: ED - Physiology Impact factor: 4.390, year: 2009

  17. Distribution and function of sodium channel subtypes in human atrial myocardium

    NARCIS (Netherlands)

    Kaufmann, Susann G.; Westenbroek, Ruth E.; Maass, Alexander H.; Lange, Volkmar; Renner, Andre; Wischmeyer, Erhard; Bonz, Andreas; Muck, Jenny; Ertl, Georg; Catterall, William A.; Scheuer, Todd; Maier, Sebastian K. G.

    Voltage-gated sodium channels composed of a pore-forming alpha subunit and auxiliary beta subunits are responsible for the upstroke of the action potential in cardiac muscle. However, their localization and expression patterns in human myocardium have not yet been clearly defined. We used

  18. Sensitization of the Guinea Pig Myocardium through the Mucous Membrane of the Digestive Tract,

    Science.gov (United States)

    Under certain conditions, sessile antibodies can be bound by the guinea - pig myocardium that had been sensitized by direct introduction of the allergen into the stomach. This is confirmed by the positive anaphylactic reaction in the isolated heart of animals treated in this manner, which reaction manifests itself in a modified heart rate when the isolated heart is challenged by the sensitizing allergen.

  19. Defined Engineered Human Myocardium with Advanced Maturation for Applications in Heart Failure Modelling and Repair

    Science.gov (United States)

    Tiburcy, Malte; Hudson, James E.; Balfanz, Paul; Schlick, Susanne; Meyer, Tim; Liao, Mei-Ling Chang; Levent, Elif; Raad, Farah; Zeidler, Sebastian; Wingender, Edgar; Riegler, Johannes; Wang, Mouer; Gold, Joseph D.; Kehat, Izhak; Wettwer, Erich; Ravens, Ursula; Dierickx, Pieterjan; van Laake, Linda W.; Goumans, Marie Jose; Khadjeh, Sara; Toischer, Karl; Hasenfuss, Gerd; Couture, Larry A.; Unger, Andreas; Linke, Wolfgang A.; Araki, Toshiyuki; Neel, Benjamin; Keller, Gordon; Gepstein, Lior; Wu, Joseph C.; Zimmermann, Wolfram-Hubertus

    2017-01-01

    Background Advancing structural and functional maturation of stem cell-derived cardiomyocytes remains a key challenge for applications in disease modelling, drug screening, and heart repair. Here, we sought to advance cardiomyocyte maturation in engineered human myocardium (EHM) towards an adult phenotype under defined conditions. Methods We systematically investigated cell composition, matrix and media conditions to generate EHM from embryonic and induced pluripotent stem cell-derived cardiomyocytes and fibroblasts with organotypic functionality under serum-free conditions. We employed morphological, functional, and transcriptome analyses to benchmark maturation of EHM. Results EHM demonstrated important structural and functional properties of postnatal myocardium, including: (1) rod-shaped cardiomyocytes with M-bands assembled as a functional syncytium; (2) systolic twitch forces at a similar level as observed in bona fide postnatal myocardium; (3) a positive force-frequency-response; (4) inotropic responses to β-adrenergic stimulation mediated via canonical β1- and β2-adrenoceptor signaling pathways; and (5) evidence for advanced molecular maturation by transcriptome profiling. EHM responded to chronic catecholamine toxicity with contractile dysfunction, cardiomyocyte hypertrophy, cardiomyocyte death, and NT-proBNP release; all are classical hallmarks of heart failure. Additionally, we demonstrate scalability of EHM according to anticipated clinical demands for cardiac repair. Conclusions We provide proof-of-concept for a universally applicable technology for the engineering of macro-scale human myocardium for disease modelling and heart repair from embryonic and induced pluripotent stem cell-derived cardiomyocytes under defined, serum-free conditions. PMID:28167635

  20. Defined Engineered Human Myocardium With Advanced Maturation for Applications in Heart Failure Modeling and Repair.

    Science.gov (United States)

    Tiburcy, Malte; Hudson, James E; Balfanz, Paul; Schlick, Susanne; Meyer, Tim; Chang Liao, Mei-Ling; Levent, Elif; Raad, Farah; Zeidler, Sebastian; Wingender, Edgar; Riegler, Johannes; Wang, Mouer; Gold, Joseph D; Kehat, Izhak; Wettwer, Erich; Ravens, Ursula; Dierickx, Pieterjan; van Laake, Linda W; Goumans, Marie Jose; Khadjeh, Sara; Toischer, Karl; Hasenfuss, Gerd; Couture, Larry A; Unger, Andreas; Linke, Wolfgang A; Araki, Toshiyuki; Neel, Benjamin; Keller, Gordon; Gepstein, Lior; Wu, Joseph C; Zimmermann, Wolfram-Hubertus

    2017-05-09

    Advancing structural and functional maturation of stem cell-derived cardiomyocytes remains a key challenge for applications in disease modeling, drug screening, and heart repair. Here, we sought to advance cardiomyocyte maturation in engineered human myocardium (EHM) toward an adult phenotype under defined conditions. We systematically investigated cell composition, matrix, and media conditions to generate EHM from embryonic and induced pluripotent stem cell-derived cardiomyocytes and fibroblasts with organotypic functionality under serum-free conditions. We used morphological, functional, and transcriptome analyses to benchmark maturation of EHM. EHM demonstrated important structural and functional properties of postnatal myocardium, including: (1) rod-shaped cardiomyocytes with M bands assembled as a functional syncytium; (2) systolic twitch forces at a similar level as observed in bona fide postnatal myocardium; (3) a positive force-frequency response; (4) inotropic responses to β-adrenergic stimulation mediated via canonical β 1 - and β 2 -adrenoceptor signaling pathways; and (5) evidence for advanced molecular maturation by transcriptome profiling. EHM responded to chronic catecholamine toxicity with contractile dysfunction, cardiomyocyte hypertrophy, cardiomyocyte death, and N-terminal pro B-type natriuretic peptide release; all are classical hallmarks of heart failure. In addition, we demonstrate the scalability of EHM according to anticipated clinical demands for cardiac repair. We provide proof-of-concept for a universally applicable technology for the engineering of macroscale human myocardium for disease modeling and heart repair from embryonic and induced pluripotent stem cell-derived cardiomyocytes under defined, serum-free conditions. © 2017 American Heart Association, Inc.

  1. [Effect of compound danshen dripping pill combined with intravenous transplantation of human umbilical cord blood mononuclear cells on local inflammatory response in the myocardium of rabbits with acute myocardial infarction].

    Science.gov (United States)

    Deng, Liu-xia; Yu, Guo-long; Al, Qi; Yuan, Chun-ju

    2013-11-01

    To investigate effect of Compound Danshen Dripping Pill (CDDP) on the inflammatory response of the myocardium of acute myocardial infarction (AMI) rabbits, to observe the therapeutic effect of CDDP combined intravenous transplantation of human umbilical cord blood mononuclear cells (HUCBMCs) on inflammatory response, pro-inflammatory cytokine tumor necrosis factor alpha (TNF-alpha) , and heart function in the myocardium of AMI rabbits, and to explore the possible protective mechanisms of the combined therapy. The AMI model was successfully established by ligation of the left anterior coronary artery (LAD) in 40 healthy rabbits.Then they were randomly divided into four groups, i.e., the control group, the CDDP group, the transplantation group, and the combined group, 10 in each group. Rabbits in the control group received intravenous injection of 0.5 mL normal saline via ear vein within 24 h after AMI and then intragastric infusion of normal saline at 5 mL per day. Rabbits in the CDDP group received intravenous injection of 0.5 mL normal saline via ear vein within 24 h after AMI and then intragastric infusion of solution obtained by solving 270 mg CDDP in 5 mL normal saline per day. Rabbits in the transplantation group received intravenous injection of 0.5 mL normal saline labeled with green fluorescent protein (GFP) containing 3 x 10(7) of HUCBMCs via ear vein within 24 h after AMI and then intragastric infusion of normal saline at 5 mL per day. Rabbits in the combined group received intravenous injection of 0.5 mL normal saline labeled with GFP containing 3 x 10(7) of HUCBMCs via ear vein within 24 h after AMI and then intragastric infusion of solution obtained by solving 270 mg CDDP in 5 mL normal saline per day. At week 1 and 4 after treatment, cardiac function indices such as left ventricular fractional shorting (LVFS) and left ventricular ejection fraction (LVEF) were performed by echocardiography; the number of transplanted cells in the myocardium was found

  2. Radiolabeled Rhein as Small-Molecule Necrosis Avid Agents for Imaging of Necrotic Myocardium.

    Science.gov (United States)

    Luo, Qi; Jin, Qiaomei; Su, Chang; Zhang, Dongjian; Jiang, Cuihua; Fish, Anne Folta; Feng, Yuanbo; Ni, Yicheng; Zhang, Jian; Yin, Zhiqi

    2017-01-17

    A rapid and accurate identification of necrotic myocardium is of great importance for diagnosis, risk stratification, clinical decision-making, and prognosis evaluation of myocardial infarction. Here, we explored technetium-99m labeled rhein derivatives for rapid imaging of the necrotic myocardium. Three hydrazinonicotinic acid-linker-rhein (HYNIC-linker-rhein) derivatives were synthesized, and then, these synthetic compounds were labeled with technetium-99m using ethylenediaminediacetic acid (EDDA) and tricine as coligands [ 99m Tc(EDDA)-HYNIC-linker-rhein]. The necrosis avidity of the three 99m Tc-labeled rhein derivatives was tested in a mouse model of ethanol-induced muscular necrosis by gamma counting, histochemical staining, and autoradiography. A lead tracer for visualization of necrotic myocardium was assessed by single photon emission computed tomography/computed tomography (SPECT/CT) imaging in a rat model with reperfused myocardial infarction. The necrosis avidity mechanism of the tracer was explored by DNA binding studies in vitro and blocking experiments in vivo. Results showed that the uptake in necrotic muscles of the three 99m Tc-compounds was higher than that in viable muscles (P EDDA)-HYNIC-ethylenediamine-rhein [ 99m Tc(EDDA)-HYNIC-2C-rhein] displayed the best distribution profiles for imaging. The necrotic myocardium lesions were clearly visualized by SPECT/CT using 99m Tc(EDDA)-HYNIC-2C-rhein at 1 h after injection. The necrotic-to-viable myocardium and necrotic myocardium-to-blood uptake ratios of 99m Tc(EDDA)-HYNIC-2C-rhein were 4.79 and 3.02 at 1 h after injection. DNA binding studies suggested HYNIC-linker-rhein bound to DNA through intercalation. The uptake of 99m Tc(EDDA)-HYNIC-2C-rhein in necrotic muscle was significantly blocked by excessive unlabeled rhein, with 77.61% decline at 1 h after coinjection. These findings suggested 99m Tc(EDDA)-HYNIC-2C-rhein emerged as a "hot spot" imaging probe that has a potential for rapid imaging of

  3. Right Ventricular Pseudoaneurysm Following Endomyocardial Biopsy.

    Science.gov (United States)

    Pita; Santos; Manteiga; Rodriguez; Beiras

    1996-03-01

    Ventricular perforation is an unusual complication after endomyocardial biopsy in heart transplanted patients. We report a case of asymptomatic right ventricular perforation and pseudoaneurysm formation, secondary to endomyocardial biopsy, diagnosed by angiography. The spontaneous obliteration of the pseudoaneurysm was observed.

  4. Decline of Phosphotransfer and Substrate Supply Metabolic Circuits Hinders ATP Cycling in Aging Myocardium.

    Directory of Open Access Journals (Sweden)

    Emirhan Nemutlu

    Full Text Available Integration of mitochondria with cytosolic ATP-consuming/ATP-sensing and substrate supply processes is critical for muscle bioenergetics and electrical activity. Whether age-dependent muscle weakness and increased electrical instability depends on perturbations in cellular energetic circuits is unknown. To define energetic remodeling of aged atrial myocardium we tracked dynamics of ATP synthesis-utilization, substrate supply, and phosphotransfer circuits through adenylate kinase (AK, creatine kinase (CK, and glycolytic/glycogenolytic pathways using 18O stable isotope-based phosphometabolomic technology. Samples of intact atrial myocardium from adult and aged rats were subjected to 18O-labeling procedure at resting basal state, and analyzed using the 18O-assisted HPLC-GC/MS technique. Characteristics for aging atria were lower inorganic phosphate Pi[18O], γ-ATP[18O], β-ADP[18O], and creatine phosphate CrP[18O] 18O-labeling rates indicating diminished ATP utilization-synthesis and AK and CK phosphotransfer fluxes. Shift in dynamics of glycolytic phosphotransfer was reflected in the diminished G6P[18O] turnover with relatively constant glycogenolytic flux or G1P[18O] 18O-labeling. Labeling of G3P[18O], an indicator of G3P-shuttle activity and substrate supply to mitochondria, was depressed in aged myocardium. Aged atrial myocardium displayed reduced incorporation of 18O into second (18O2, third (18O3, and fourth (18O4 positions of Pi[18O] and a lower Pi[18O]/γ-ATP[18 O]-labeling ratio, indicating delayed energetic communication and ATP cycling between mitochondria and cellular ATPases. Adrenergic stress alleviated diminished CK flux, AK catalyzed β-ATP turnover and energetic communication in aging atria. Thus, 18O-assisted phosphometabolomics uncovered simultaneous phosphotransfer through AK, CK, and glycolytic pathways and G3P substrate shuttle deficits hindering energetic communication and ATP cycling, which may underlie energetic

  5. Subacute ghrelin administration inhibits apoptosis and improves ultrastructural abnormalities in remote myocardium post-myocardial infarction.

    Science.gov (United States)

    Eid, Refaat A; Zaki, Mohamed Samir Ahmed; Al-Shraim, Mubarak; Eleawa, Samy M; El-Kott, Attalla Farag; Al-Hashem, Fahaid H; Eldeen, Muhammad Alaa; Ibrahim, Hoja; Aldera, Hussain; Alkhateeb, Mahmoud A

    2018-05-01

    This study investigated the effect of ghrelin on cardiomyocytes function, apoptosis and ultra-structural alterations of remote myocardium of the left ventricle (LV) of rats, 21 days post myocardial infarction (MI). Rats were divided into 4 groups as a control, a sham-operated rats, a sham-operated+ghrelin, an MI + vehicle and an MI + ghrelin-treated rats. MI was induced by LAD ligation and then rats were recievd a concomitant doe of either normal saline as a vehicle or treated with ghrelin (100 μg/kg S.C., 2x/day) for 21 consecutive days. Ghrelin enhanced myocardial contractility in control rats and reversed the decreases in myocardial contractility and the increases in the serum levels of CK-MB and LDH in MI-induced rats. Additionally, it inhibited the increases in levels of Bax and cleaved caspase 3 and increased those for Bcl-2 in the remote myocardium of rat's LV, post-MI. At ultra-structural level, while ghrelin has no adverse effects on LV myocardium obtained from control or sham-treated rats, ghrelin post-administration to MI-induced rats reduced vascular formation, restored normal microfilaments appearance and organization, preserved mitochondria structure, and prevented mitochondrial swelling, collagen deposition and number of ghost bodies in the remote areas of their LV. Concomitantly, in remote myocardium of MI-induced rats, ghrelin enhanced endoplasmic reticulum intracellular organelles count, decreased number of atrophied nuclei and phagocytes, diminished the irregularity in the nuclear membranes and inhibited chromatin condensation. In conclusion, in addition to the physiological, biochemical and molecular evidence provided, this is the first study that confirms the anti-apoptotic effect of ghrelin in the remote myocardium of the LV during late MI at the level of ultra-structural changes. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

  6. Clinical usefulness of cine MRI for evaluation of left ventricular volume and diagnosis of heart and great vessel diseases

    Energy Technology Data Exchange (ETDEWEB)

    Kondo, Takeshi; Anno, Hirofumi; Uritani, Tomizo [Fujita-Gakuen Health Univ., Toyoake, Aichi (Japan); and others

    1990-01-01

    ECG-gated cine mode magnetic resonance (MR) imaging was performed in 20 patients with various heart deseases. Left ventricular volume (LVV) and left ventricular ejection fraction (LVEF) were calculated on MR images obtained in left ventricular vertical and horizontal long axis views. The findings were compared with those obtained from left ventriculography. There was a significant positive correlation between MR imaging and ventriculography for both LVV and LVEF (p<0.001). In Marfan syndrome after surgery for dissecting aneurysm of the aorta, MR imaging was capable of visualizing not only the whole aorta in a single plane but also enlargement of the aortic root. It also depicted asynergy and thinned wall of the infarcted myocardium for myocardial infarction; an enlarged left auricle, the thickened septum, and constricted outflow tract for idiopathic hypertrophic subaortic stenosis; shunt flow for ventricular septum defect; and an enlarged aortic root for aortitis syndrome. Using ventriculography as the standard, cine MR imaging was frequently false positive for the detection of mitral regurgitation. There was, however, good concordance between MR imaging and ventriculography in detecting aortic regurgitation. In addition, MR imaging was equivalent to color Doppler technique for detecting valvular regurgitation. (N.K.).

  7. Clinical usefulness of cine MRI for evaluation of left ventricular volume and diagnosis of heart and great vessel diseases

    International Nuclear Information System (INIS)

    Kondo, Takeshi; Anno, Hirofumi; Uritani, Tomizo

    1990-01-01

    ECG-gated cine mode magnetic resonance (MR) imaging was performed in 20 patients with various heart deseases. Left ventricular volume (LVV) and left ventricular ejection fraction (LVEF) were calculated on MR images obtained in left ventricular vertical and horizontal long axis views. The findings were compared with those obtained from left ventriculography. There was a significant positive correlation between MR imaging and ventriculography for both LVV and LVEF (p<0.001). In Marfan syndrome after surgery for dissecting aneurysm of the aorta, MR imaging was capable of visualizing not only the whole aorta in a single plane but also enlargement of the aortic root. It also depicted asynergy and thinned wall of the infarcted myocardium for myocardial infarction; an enlarged left auricle, the thickened septum, and constricted outflow tract for idiopathic hypertrophic subaortic stenosis; shunt flow for ventricular septum defect; and an enlarged aortic root for aortitis syndrome. Using ventriculography as the standard, cine MR imaging was frequently false positive for the detection of mitral regurgitation. There was, however, good concordance between MR imaging and ventriculography in detecting aortic regurgitation. In addition, MR imaging was equivalent to color Doppler technique for detecting valvular regurgitation. (N.K.)

  8. Sub-aortic obstruction of left ventricular outflow tract secondary to benfluorex-induced endocardial fibrosis

    Directory of Open Access Journals (Sweden)

    Catherine Szymanski

    2015-12-01

    Full Text Available Patients exposed to benfluorex have an increased risk of restrictive organic valvular heart disease. Aortic and mitral regurgitations caused by fibrotic valve disease are the most common features observed in exposure to fenfluramine derivatives in general and benfluorex in particular. We report here, for the first time to our knowledge, a well-documented case in which obstructive sub-aortic endocardium fibrosis within the left ventricular outflow tract is related with exposure to a drug that modifies the metabolism of serotonin. It now remains to be established whether extensive fibrosis of the myocardium in addition to well-documented valvular fibrosis may develop in patients exposed to amphetamine-derived drugs affecting the serotonin system.

  9. Life-threatening hobbies in the youth? Two autoptic cases suggesting arrhythmogenic right ventricular cardiomyopathy.

    Science.gov (United States)

    Wingenfeld, Lisa; Freislederer, Andreas; Schulze-Bahr, Eric; Paul, Matthias; Bajanowski, Thomas

    2007-08-24

    Determining the cause for the sudden death in young adults tends to be complex and difficult. Two cases of death of young people were autoptically investigated who died suddenly while carrying out their hobbies (a 22-year-old male musician and a 20-year-old female dancer). In both cases neither the police investigation, the autopsy, nor the toxicological investigations gave any relevant results. However, when investigating the histology fatty and fibrotic tissue in the right ventricle of the myocardium were found, whereas the myocytes proved to be degenerated--typical for arrhythmogenic right ventricular cardiomyopathy (ARVC). It is important to consider the possibility of heart rhythm failure if a clear reason for sudden death in young adults cannot be detected. Heart rhythm failure often involves the genetic background of the case, which suggests that genetic analysis should be carried out as a supportive means of diagnostics.

  10. Mutation analysis and evaluation of the cardiac localization of TMEM43 in arrhythmogenic right ventricular cardiomyopathy

    DEFF Research Database (Denmark)

    Christensen, A H; Andersen, C B; Tybjærg-Hansen, A

    2011-01-01

    Christensen AH, Andersen CB, Tybjærg-Hansen A, Haunso S, Svendsen JH. Mutation analysis and evaluation of the cardiac localization of TMEM43 in arrhythmogenic right ventricular cardiomyopathy. A single report has associated mutations in TMEM43 (LUMA) with a distinctive form of arrhythmogenic right...... with anti-TMEM43, anti-plakoglobin, anti-plakophilin-2, anti-connexin-43, and anti-emerin antibodies was performed on myocardium from TMEM43-positive patients (n = 3) and healthy controls (n = 3). The genetic screening identified heterozygous variants in two families: one reported mutation (c.1073C> T......; in two related patients) and one novel variant (c.705+ 7G> A; in one patient) of unknown significance. All three patients fulfilled Task Force criteria and did not carry mutations in any other ARVC-related gene. Immunostaining with TMEM43 antibody showed intense staining of the sarcolemma. The signal...

  11. Histiocytoid cardiomyopathy and ventricular noncompaction presenting as sudden death in an adult male.

    Science.gov (United States)

    Val-Bernal, J Fernando; Mayorga, Marta; Ortega, Clara; Linares, Emma

    2017-11-01

    Histiocytoid/oncocytic cardiomyopathy (HCM) is a rare, distinctive arrhythmogenic disorder that presents as arrhythmia or sudden death in infants and children. Ventricular noncompaction (VNC) is a rare cardiomyopathy characterized by a thickened endocardial layer of noncompacted myocardium and a thin epicardial layer of compacted myocardium. Only six cases of the association of both cardiomyopathies have been reported previously in the literature. All these cases were in children. To the best of our knowledge, a case of HCM has not been described in the adult. We report the case of a 45-year-old man with an increased heart weight and involvement of both ventricles by HCM and VNC cardiomyopathy. Besides, multiple foci of myocardial disorganization were detected. He died suddenly while hiking. The association of both processes HCM and VNC was an unexpected finding at autopsy. The death was linked to functional abnormalities of the cardiac histiocytoid cells, and it was favored by a state of abnormal development of the heart. Copyright © 2017 Elsevier GmbH. All rights reserved.

  12. ST segment elevation after myocardial infarction: Viability or ventricular dysfunction? Comparison with myocardial scintigraphy

    International Nuclear Information System (INIS)

    Chalela, William Azem; Soares, J. Jr.; Meneghetti, J.C.; Olivera, C.G.; Moffa, P.J.; Falcao, A.M.; Ramires, J.A.F.

    2004-01-01

    The detection of viable myocardium after myocardial infarction is an important indication for revascularization. We compared exercise-induced ST segment elevation with reversibility at Thallium-201 SPECT scintigraphy and regional wall motion assessment by ventriculography. Thirty two patients with previous myocardial infarction and with left ventricular ejection fraction of < 50% were studied. Patients underwent coronary angiography and Thallium-201 SPECT scintigraphy with re-injection protocol before and after coronary artery bypass graft surgery. Group I comprised 11 patients with ST segment elevation during treadmill stress testing. Group II comprised 21 patients without ST segment elevation. Minimal or moderate hypokinesis was present in 2 patients of Group I and in 4 patients of Group II. Nine patients of Group I and 17 patients of Group II had severe hypokinetic, akinetic or dyskinetic myocardium. Scintigraphy revealed reversibility in the myocardial infarction area in 4 patients from Group I (36.4%) and 11 (52.4%) patients from Group II. Improvement in perfusion after coronary artery bypass grafting was observed in 4 patients from Group I and 8 patients from Group II. Sensitivity, specificity, accuracy, and positive and negative predictive values of ST segment elevation were 33.3, 70.6, 55.2, 44.5 and 60% respectively. It was concluded that exercise-induced ST segment elevation after myocardial infarction is present more frequently in cases of severe regional myocardial dysfunction. (author)

  13. Impaired coronary flow reserve is the most important marker of viable myocardium in the myocardial segment-based analysis of dual-isotope gated myocardial perfusion single-photon emission computed tomography

    International Nuclear Information System (INIS)

    Lee, Won Woo; So, Young; Kim, Ki Bong; Lee, Dong Soo

    2014-01-01

    The aim of this study was to investigate the most robust predictor of myocardial viability among stress/rest reversibility (coronary flow reserve [CFR] impairment), 201 Tl perfusion status at rest, 201 Tl 24 hours redistribution and systolic wall thickening of 99m Tc-methoxyisobutylisonitrile using a dual isotope gated myocardial perfusion single-photon emission computed tomography (SPECT) in patients with coronary artery disease (CAD) who were re-vascularized with a coronary artery bypass graft (CABG) surgery. A total of 39 patients with CAD was enrolled (34 men and 5 women), aged between 36 and 72 years (mean 58 ± 8 standard in years) who underwent both pre- and 3 months post-CABG myocardial SPECT. We analyzed 17 myocardial segments per patient. Perfusion status and wall motion were semi-quantitatively evaluated using a 4-point grading system. Viable myocardium was defined as dysfunctional myocardium which showed wall motion improvement after CABG. The left ventricular ejection fraction (LVEF) significantly increased from 37.8 ± 9.0% to 45.5 ± 12.3% (p 201 Tl rest perfusion status (p = 0.024) were significant predictors of wall motion improvement. However, in multiple logistic regression analysis, stress/rest reversibility alone was a significant predictor for post-CABG wall motion improvement (p < 0.001). Stress/rest reversibility (impaired CFR) during dual-isotope gated myocardial perfusion SPECT was the single most important predictor of wall motion improvement after CABG.

  14. Comparison of the prognostic value of SPECT after nitrate administration and metabolic imaging by PET in patients with ischaemic left ventricular dysfunction

    Energy Technology Data Exchange (ETDEWEB)

    Sorrentino, Anna R.; Acampa, Wanda; Mainolfi, Ciro; Salvatore, Marco; Cuocolo, Alberto [University Federico II, Department of Biomorphological and Functional Sciences, Institute of Biostructures and Bioimages of the National Council of Research, Naples (Italy); Petretta, Mario [University Federico II, Department of Internal Medicine, Cardiovascular and Immunological Sciences, Naples (Italy)

    2007-04-15

    We compared the prognostic value of {sup 99m}Tc-tetrofosmin single-photon emission computed tomography (SPECT) after nitrate administration and positron emission tomography (PET) with {sup 18}F-fluorodeoxyglucose (FDG) in patients with ischaemic left ventricular (LV) dysfunction. Eighty-nine patients with previous myocardial infarction and LV dysfunction (LV ejection fraction 33 {+-} 10%) underwent {sup 99m}Tc-tetrofosmin SPECT under control conditions (baseline) and after sublingual administration of 10 mg of isosorbide dinitrate (nitrate). Within 1 week, all patients underwent PET imaging with {sup 18}F-FDG. Four patients were excluded because of inadequate FDG uptake caused by severe diabetes. Follow-up data were obtained by phone contact with patients and by review of hospital or physicians' records. Cardiac death, myocardial infarction and late revascularisation for unstable angina were considered as events. Follow-up data were not available in three patients. Follow-up was 96% complete at a mean period of 29 {+-} 19 months. At baseline SPECT, 59 (72%) patients had evidence of viable myocardium, while 23 did not. Of these latter patients, 12 (52%) demonstrated viable myocardium after nitrate and 13 (56%) had preserved metabolic activity. Cardiac events (cardiac death, myocardial infarction and late revascularisation for unstable angina) occurred in 24 (29%) patients. Event-free survival was similar in patients with and patients without viable myocardium at baseline SPECT (p = 0.8). In contrast, event-free survival was lower in patients with viable myocardium at nitrate SPECT and PET compared to those without viable myocardium (both p<0.05). In patients with ischaemic LV dysfunction, the prognostic value of SPECT imaging after nitrate is comparable to that of PET metabolic imaging. (orig.)

  15. A quantitative index of regional blood flow in canine myocardium derived noninvasively with N-13 ammonia and dynamic positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Nienaber, C.A.; Ratib, O.; Gambhir, S.S.; Krivokapich, J.; Huang, S.C.; Phelps, M.E.; Schelbert, H.R. (Univ. of California, Los Angeles School of Medicine (USA))

    1991-01-01

    To derive a quantitative index of regional myocardial blood flow, the arterial input function of the flow tracer N-13 ammonia and the regional myocardial N-13 activity concentrations were noninvasively determined in 29 experiments in eight dogs. N-13 ammonia was administered intravenously and cross-sectional images were acquired dynamically using an ECAT III positron emission tomograph with an effective in-plane resolution of 13.46 mm full-width half-maximum. Time-activity curves were derived from the serial images by assigning regions of interest to the left ventricular myocardium and left ventricular blood pool. Tracer net extractions were estimated from the myocardial time-activity concentrations at various times after tracer injection and the integral of the arterial input function. Myocardial blood flow was altered by intravenous dipyridamole, morphine, propranolol and partial or complete occlusion of the left anterior descending coronary artery, and ranged from 9 to 860 ml/min per 100 g. Estimates of tracer net extractions were most accurate when determined from the myocardial N-13 activity concentrations at 60 s divided by the integral of the arterial input function to that time. These estimates correlated with regional myocardial blood flows determined independently by the microsphere technique by y = x (1 - 0.64(e-114/x); SEE = 22.9; r = 0.94). First pass extraction fractions of N-13 ammonia determined noninvasively with this approach declined with higher flows in a nonlinear fashion and were similar to those determined invasively by direct intracoronary N-13 ammonia injections. The findings indicate that an accurate index of regional myocardial blood flow can be obtained noninvasively by high temporal sampling of arterial and myocardial tracer activity concentrations with positron emission tomography.

  16. Congenital left ventricular wall abnormalities in adults detected by gated cardiac multidetector computed tomography: Clefts, aneurysms, diverticula and terminology problems

    International Nuclear Information System (INIS)

    Erol, Cengiz; Koplay, Mustafa; Olcay, Ayhan; Kivrak, Ali Sami; Ozbek, Seda; Seker, Mehmet; Paksoy, Yahya

    2012-01-01

    Objectives: Our aim was to evaluate congenital left ventricular wall abnormalities (clefts, aneurysms and diverticula), describe and illustrate imaging features, discuss terminology problems and determine their prevalence detected by cardiac CT in a single center. Materials and methods: Coronary CT angiography images of 2093 adult patients were evaluated retrospectively in order to determine congenital left ventricular wall abnormalities. Results: The incidence of left ventricular clefts (LVC) was 6.7% (141 patients) and statistically significant difference was not detected between the sexes regarding LVC (P = 0.5). LVCs were single in 65.2% and multiple in 34.8% of patients. They were located at the basal to mid inferoseptal segment of the left ventricle in 55.4%, the basal to mid anteroseptal segment in 24.1%, basal to mid inferior segment in 17% and septal–apical septal segment in 3.5% of cases. The cleft length ranged from 5 to 22 mm (mean 10.5 mm) and they had a narrow connection with the left ventricle (mean 2.5 mm). They were contractile with the left ventricle and obliterated during systole. Congenital left ventricular septal aneurysm that was located just under the aortic valve was detected in two patients (0.1%). No case of congenital left ventricular diverticulum was detected. Conclusion: Cardiac CT allows us to recognize congenital left ventricular wall abnormalities which have been previously overlooked in adults. LVC is a congenital structural variant of the myocardium, is seen more frequently than previously reported and should be differentiated from aneurysm and diverticulum for possible catastrophic complications of the latter two.

  17. Usefulness of {sup 201}Tl myocardial perfusion SPECT in prediction of left ventricular remodeling following an acute myocardial infarction

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Seok Nam; Park, C. H.; Hwang, Kyung Hoon [Ajou Univ. College of Medicine, Suwon (Korea, Republic of)

    2000-02-01

    We investigated the role of myocardial perfusion SPECT in prediction of ventricular dilatation and the role of revascularization including thrombolytic therapy and PTCA in prevention of ventricular dilatation after an acute myocardial linfarction (AMI). We performed dipyridamole stress, 4 hour redistribution, and 24 hour reinjection Tl-201 SPECT in 6 patients with AMI two to nine days after attack. Perfusion and wall motion abnormalities were quantified by perfusion index(PI) and wall motion index (WMI). Left ventricular ejection fraction (LVEF), WMI and ventricular volume were measured within 1 week of AMI and after average of 6 months. According to serial changes of left ventricular end-diastolic volume (LVEDV), patients were divided into two groups. We compared WMI, PI and LVEF between the two groups. Relationships among degree of volume, stress-rest PI, WMI, CKMB,Q wave, LVEF and revascularization were analysed using multivariate analysis. Only initial rest perfusion index was significantly different between the two groups (p<0.05). While initial LVEF, stress PI, CKMB, trial of revascularization procedure, presence of Q wave and WMI were not significantly different between the two groups. Eight of 16 patients (50%) showed LV dilatation on follow-up echocardiography. Three of 3 patients (100%) who did not undergo revascualrization procedure documented LV dilatation. And only 5 (38%) of the remaining 13 patients who underwent revascularization revealed LV dilatation. There was no difference in infarct location between the two groups. By multivariate linear regression analysis in patients only undergoing revascularization, rest perfusion index was the only significant factor. Myocardial perfusion SPECT performed prior to revascularization was useful in prediction of LV dilatation after an AMI. Rest perfusion index on myocardial perfusion plays as a significant predictor of left ventricular dilatation after AMI. And revascularization appears to be a valuable

  18. Signal analysis of ventricular fibrillation

    NARCIS (Netherlands)

    Herbschleb, J.N.; Heethaar, R.M.; Tweel, L.H. van der; Zimmerman, A.N.E.; Meijler, F.L.

    Signal analysis of electro(cardio)grams during ventricular fibrillation (VF) in dogs and human patients indicates more organization and regularity than the official WHO definition suggests. The majority of the signal is characterized by a power spectrum with narrow, equidistant peaks. In a further

  19. Fractal analysis of phasic laser images of the myocardium for the purpose of diagnostics of acute coronary insufficiency

    Science.gov (United States)

    Wanchuliak, O. Y.; Bachinskyi, V. T.

    2011-09-01

    In this work on the base of Mueller-matrix description of optical anisotropy, the possibility of monitoring of time changes of myocardium tissue birefringence, has been considered. The optical model of polycrystalline networks of myocardium is suggested. The results of investigating the interrelation between the values correlation (correlation area, asymmetry coefficient and autocorrelation function excess) and fractal (dispersion of logarithmic dependencies of power spectra) parameters are presented. They characterize the distributions of Mueller matrix elements in the points of laser images of myocardium histological sections. The criteria of differentiation of death coming reasons are determined.

  20. Alternative right ventricular pacing sites.

    Science.gov (United States)

    Łuciuk, Dariusz; Łuciuk, Marek; Gajek, Jacek

    2015-01-01

    The main adverse effect of chronic stimulation is stimulation-induced heart failure in case of ventricular contraction dyssynchrony. Because of this fact, new techniques of stimulation should be considered to optimize electrotherapy. One of these methods is pacing from alternative right ventricular sites. The purpose of this article is to review currently accumulated data about alternative sites of cardiac pacing. Medline and PubMed bases were used to search English and Polish reports published recently. Recent studies report a deleterious effect of long term apical pacing. It is suggested that permanent apical stimulation, by omitting physiological conduction pattern with His-Purkinie network, may lead to electrical and mechanical dyssynchrony of heart muscle contraction. In the long term this pathological situation can lead to severe heart failure and death. Because of this, scientists began to search for some alternative sites of cardiac pacing to reduce the deleterious effect of stimulation. Based on current accumulated data, it is suggested that the right ventricular outflow tract, right ventricular septum, direct His-bundle or biventricular pacing are better alternatives due to more physiological electrical impulse propagation within the heart and the reduction of the dyssynchrony effect. These methods should preserve a better left ventricular function and prevent the development of heart failure in permanent paced patients. As there is still not enough, long-term, randomized, prospective, cross-over and multicenter studies, further research is required to validate the benefits of using this kind of therapy. The article should pay attention to new sites of cardiac stimulation as a better and safer method of treatment.

  1. Modern nuclear cardiac imaging in diagnosis and clinical management of patients with left ventricular dysfunction.

    Science.gov (United States)

    Abidov, A; Hachamovitch, R; Berman, D S

    2004-12-01

    Congestive heart failure (CHF) has become a large social burden in modern Western society, with very high morbidity and mortality and extremely large financial costs. The largest cause of CHF is coronary heart disease, with ventricular dysfunction that may or may not be reversible by revascularization. Thus, evaluation of the viable myocardial tissue in patients with ischemic left ventricular (LV) dysfunction has important clinical and therapeutic implications. Furthermore, since patients with ventricular dysfunction are at higher operative risk, cardiologists and cardiac surgeons are commonly faced with issues regarding the balance between the potential risk vs benefit of revascularization procedures. Cardiac nuclear imaging [myocardial perfusion SPECT (MPS) and positron emission tomography (PET)] provide objective information that augments standard clinical and angiographic assessments of patients with ventricular dysfunction with respect to diagnosis (etiology), prognosis, and potential benefit from intervention. Development of the technology and methodology of gated MPS, now the routine method for MPS, allows assessment of the extent and severity of inducible ischemia as well as hypoperfused but viable myocardium, and also provides measurements of LV ejection fraction, regional wall motion, LV volume measurements, diastolic function and LV geometry. With PET, myocardial metabolism and blood flow reserve can be added to the measurements provided by nuclear cardiology procedures. This paper provides insight into the current evidence regarding settings in which nuclear cardiac imaging procedures are helpful in assessment of patients in the setting of coronary artery disease with severe LV dysfunction. A risk-benefit approach to MPS results is proposed, with principal focus on identifying patients at risk for major cardiac events who may benefit from myocardial revascularization.

  2. Release of atrial natriuretic peptide from rat myocardium in vitro: effect of minoxidil-induced hypertrophy.

    Science.gov (United States)

    Kinnunen, P.; Taskinen, T.; Leppäluoto, J.; Ruskoaho, H.

    1990-01-01

    1. Ventricular hypertrophy is characterized by stimulation of ventricular synthesis of atrial natriuretic peptide (ANP). To examine the role of ventricular ANP levels in the secretion of ANP into the circulation, atrial and ventricular levels of immunoreactive-ANP (IR-ANP) as well as ANP messenger RNA (mRNA), and the release of IR-ANP from isolated perfused hearts, both before and after atrialectomy, were measured simultaneously in control and minoxidil-treated Wistar-Kyoto (WKY) and spontaneously hypertensive (SHR) rats. 2. IR-ANP levels in the ventricles of untreated, 12 month-old SHR with severe ventricular hypertrophy were increased when compared to age-matched WKY rats. Minoxidil treatment for 8 weeks in both strains resulted in a decrease in mean arterial pressure and increases in ventricular weight to body weight ratios, plasma IR-ANP concentrations (in WKY from 133 +/- 20 to 281 +/- 34 pg ml-1, P less than 0.01; in SHR from 184 +/- 38 to 339 +/- 61 pg ml-1, P less than 0.05), and in ventricular IR-ANP contents (in WKY: 53%; in SHR: 41%). A highly significant correlation was found between ventricular IR-ANP content and ventricular weight to body weight ratio (r = 0.59, P less than 0.001, n = 26). 3. When studied in vitro, in isolated perfused heart preparations, the hypertrophied ventricular tissue after atrialectomy secreted more ANP into the perfusate than ventricles of the control hearts; ventricles contributed 28%, 22%, 18% and 15% of the total ANP release to perfusate in the minoxidil-treated SHR, control SHR, minoxidil-treated WKY and control WKY, respectively.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2141796

  3. Enhancer evolution across 20 mammalian species

    DEFF Research Database (Denmark)

    Villar, Diego; Berthelot, Camille; Aldridge, Sarah

    2015-01-01

    The mammalian radiation has corresponded with rapid changes in noncoding regions of the genome, but we lack a comprehensive understanding of regulatory evolution in mammals. Here, we track the evolution of promoters and enhancers active in liver across 20 mammalian species from six diverse orders...... by profiling genomic enrichment of H3K27 acetylation and H3K4 trimethylation. We report that rapid evolution of enhancers is a universal feature of mammalian genomes. Most of the recently evolved enhancers arise from ancestral DNA exaptation, rather than lineage-specific expansions of repeat elements....... These results provide important insight into the functional genetics underpinning mammalian regulatory evolution....

  4. The right ventricular response to ventricular hypofunction in anteroseptal infarction

    International Nuclear Information System (INIS)

    Kanayama, Sugako

    1992-01-01

    Thirty-seven patients with acute anteroseptal infarction but not significant right coronary artery stenosis were examined by using thallium-201 (Tl-201) myocardial perfusion SPECT to determine how the right ventricular (RV) free wall responded to a severely impaired ventricular septum. The patients were divided into the group in which RV free wall was visualized on Tl-201 myocardial SPECT (n=19, RV(+) Group) and the group in which it was not visualized (n=18, RV(-) Group). The relationship between visualization of RV free wall and both RV and left ventricular (LV) function was evaluated. RV(+) Group had larger extent of anteroseptal necrosis and severer impairment of RV free wall, as compared with RV(-) Group. LV ejection fraction (LVEF) was significantly lower in RV(+) Group than RV(-) Group in both acute and chronic phases. Although RV ejection fraction (RVEF) in acute phase was significantly lower in RV(+) Group than RV(-) Group, it did not differ in chronic phase between the two groups. In RV(+) Group, RV stroke work index (RVSWI), pulmonary artery end diastolic pressure (PAEDP), and mean pulmonary artery pressure (MPA) in chronic phase showed a statistically significant increase compared with those in acute phase; these hemodynamic variables in chronic phase were also significantly higher than those in RV(-) Group. RV/LV ratio inversely correlated with LVEF, and both necrotic extent and impairment severity positively correlated with both PAEDP and MPA. RV free wall could be visualized more clearly, corresponding to extremely decreased LV function. These findings suggest that RV free wall may play an important role in maintaining LV and RV function when ventricular septum is severely impaired by anteroseptal infarction. (N.K.)

  5. Acidosis slows electrical conduction through the atrio-ventricular node.

    Science.gov (United States)

    Nisbet, Ashley M; Burton, Francis L; Walker, Nicola L; Craig, Margaret A; Cheng, Hongwei; Hancox, Jules C; Orchard, Clive H; Smith, Godfrey L

    2014-01-01

    Acidosis affects the mechanical and electrical activity of mammalian hearts but comparatively little is known about its effects on the function of the atrio-ventricular node (AVN). In this study, the electrical activity of the epicardial surface of the left ventricle of isolated Langendorff-perfused rabbit hearts was examined using optical methods. Perfusion with hypercapnic Tyrode's solution (20% CO2, pH 6.7) increased the time of earliest activation (Tact) from 100.5 ± 7.9 to 166.1 ± 7.2 ms (n = 8) at a pacing cycle length (PCL) of 300 ms (37°C). Tact increased at shorter PCL, and the hypercapnic solution prolonged Tact further: at 150 ms PCL, Tact was prolonged from 131.0 ± 5.2 to 174.9 ± 16.3 ms. 2:1 AVN block was common at shorter cycle lengths. Atrial and ventricular conduction times were not significantly affected by the hypercapnic solution suggesting that the increased delay originated in the AVN. Isolated right atrial preparations were superfused with Tyrode's solutions at pH 7.4 (control), 6.8 and 6.3. Low pH prolonged the atrial-Hisian (AH) interval, the AVN effective and functional refractory periods and Wenckebach cycle length significantly. Complete AVN block occurred in 6 out of 9 preparations. Optical imaging of conduction at the AV junction revealed increased conduction delay in the region of the AVN, with less marked effects in atrial and ventricular tissue. Thus acidosis can dramatically prolong the AVN delay, and in combination with short cycle lengths, this can cause partial or complete AVN block and is therefore implicated in the development of brady-arrhythmias in conditions of local or systemic acidosis.

  6. Acidosis slows electrical conduction through the atrio-ventricular node

    Directory of Open Access Journals (Sweden)

    Ashley Muir Nisbet

    2014-06-01

    Full Text Available Acidosis affects the mechanical and electrical activity of mammalian hearts but comparatively little is known about its effects on the function of the atrio-ventricular node (AVN. In this study, the electrical activity of the epicardial surface of the left ventricle of isolated Langendorff-perfused rabbit hearts was examined using optical methods. Perfusion with hypercapnic Tyrode’s solution (20% CO2, pH 6.7 increased the time of earliest activation (Tact from 100.5+7.9 to 166.1+7.2ms (n=8 at a pacing cycle length (PCL of 300ms (37oC. Tact increased at shorter PCL, and the hypercapnic solution prolonged Tact further: at 150ms PCL, Tact was prolonged from 131.0+5.2 to 174.9+16.3ms. 2:1 AVN block was common at shorter cycle lengths. Atrial and ventricular conduction times were not significantly affected by the hypercapnic solution suggesting that the increased delay originated in the AVN. Isolated right atrial preparations were superfused with Tyrode’s solutions at pH 7.4 (control, 6.8 and 6.3. Low pH prolonged the atrial-Hisian (AH interval, the effective and functional refractory periods and Wenckebach cycle length significantly. Complete AVN block occurred in 6 out of 9 preparations. Optical imaging of conduction at the AV junction revealed increased conduction delay in the region of the AVN, with less marked effects in atrial and ventricular tissue. Thus acidosis can dramatically prolong the AVN delay, and in combination with short cycle lengths, this can cause partial or complete AVN block and is therefore implicated in the development of brady-arrhythmias in conditions of local or systemic acidosis.

  7. Kronisk iskaemisk hjerteinsufficiens. Revaskularisering bedrer overlevelsen blandt patienter med hibernating myocardium

    DEFF Research Database (Denmark)

    Holdgaard, Paw Chr; Nielsen, Søren Steen; Wiggers, Henrik

    2007-01-01

    imaging was performed with 99mTc-sestamibi and glucose metabolism was visualized with 18F-fluorodeoxyglucose (18F-FDG) gamma camera PET. Medical records and death certificate were reviewed retrospectively. RESULTS: 50 patients were included. We found an increased survival among patients with HIB who......INTRODUCTION: Patients with ischemic heart failure and reversible dysfunctional myocardium (Hibernating myocardium, HIB) can benefit from revascularization. These patients can be selected with nuclear methods. The purpose of this study was to describe the results of the imaging procedures...... in patients tested for HIB and relate the results to the choice of treatment and cause of death. MATERIALS AND METHODS: During a 2-year period 51 patients were referred to determine the amount of HIB. This can be determined with blood flow and metabolic imaging of the heart. Resting-myocardial perfusion...

  8. Distinction of salvaged and infarcted myocardium within the ischaemic area-at-risk with T2 mapping

    DEFF Research Database (Denmark)

    Hammer-Hansen, Sophia; Ugander, Martin; Hsu, Li-Yueh

    2014-01-01

    values from T2 maps and signal intensities on T2-weighted images were measured in the corresponding areas. RESULTS: At both imaging time points, the T2 of the salvaged myocardium was longer than of remote (66.0 ± 6.9 vs. 51.4 ± 3.5 ms, P ...AIM: Area-at-risk (AAR) measurements often rely on T2-weighted images, but subtle differences in T2 may be overlooked with this method. To determine the differences in oedema between salvaged and infarcted myocardium, we performed quantitative T2 mapping of the AAR. We also aimed to determine...... (14.7 ± 5.6 vs. 8.7 ± 5.1 ms, P = 0.02). CONCLUSIONS: T2 relaxation parameters are different in the infarcted and salvaged myocardium, and both are significantly longer than remote. Furthermore, the magnitude of increase in T2 was less in the salvaged myocardium after longer reperfusion, indicating...

  9. The contribution of nuclear medicine in the six months following a myocardium infarction

    International Nuclear Information System (INIS)

    Franken, Ph.R.

    2002-01-01

    The techniques of nuclear medicine allow to estimate the myocardial infarction size, to measure the ejection fraction and the ventricles volumes and to identify the presence of high-risk and viable myocardium. This information is essential to evaluate the important complications risks after an acute myocardial infarction, that is to say the infarction recurrence and the cardiac death coming from rhythm troubles or a left ventricle failure. (N.C.)

  10. Effect of hyperbaric oxygenation on carbohydrate metabolism protein synthesis in the myocardium during sustained hypodynamia

    Science.gov (United States)

    Makarov, G. A.

    1980-01-01

    Glycolysis and the intensity of protein synthesis were studied in 140 white male rats in subcellular fractions of the myocardium during 45 day hypodynamia and hyperbaric oxygenation. Hypodynamia increased: (1) the amount of lactic acids; (2) the amount of pyruvic acid; (3) the lactate/pyruvate coefficient; and (4) the activities of aldolase and lactate dehydrogenase. Hyperbaric oxygenation was found to have a favorable metabolic effect on the animals with hypodynamia.

  11. Imaging of the myocardium using {sup 18}F-FDG-PET/MRI

    Energy Technology Data Exchange (ETDEWEB)

    Ferda, Jiří, E-mail: ferda@fnplzen.cz [Clinic of the Imaging Methods, University Hospital Plzen, Alej Svobody 80, 304 60 Plzeň (Czech Republic); Hromádka, Milan, E-mail: hromadkam@fnplzen.cz [Department of Cardiology, University Hospital Plzen, Alej Svobody 80, 304 60 Plzeň (Czech Republic); Baxa, Jan, E-mail: baxaj@fnplzen.cz [Clinic of the Imaging Methods, University Hospital Plzen, Alej Svobody 80, 304 60 Plzeň (Czech Republic)

    2016-10-15

    Highlights: • The natural combination of the metabolic and structural information is the most important strenghtof myocardial PET/MRI. • Metabolic conversion to glycolysis is needed in the assesment ov the viable myocardium. • Metabolic conversion to the fatty acid metabolism is the crucial in the assesment of the ischemic memory and myocardial inflammation. - Abstract: The introduction of the integrated hybrid PET/MRI equipment creates the possibility to perform PET and MRI simultaneously. Depending on the clinical question, the metabolic conversion to glycolytic activity or beta-oxidation is performed before the application of FDG. Since FDG aids to evaluate the energetic metabolism of the myocytes and myocardial MRI reaches the imaging capabilities of perfusion and tissue characterization in the daily routine, FDG-PET/MRI looks to be a promising method of PET/MRI exploitation in cardiac imaging. When myocardial FDG uptake should be evaluated in association with the perfusion distribution, the cross-evaluation of FDG accumulation distribution and perfusion distribution pattern is necessary. The different scenarios may be used in the assessment of myocardium, the conversion to glycolytic activity is used in the imaging of the viable myocardium, but the glycolytic activity suppression might be used in the indications of the identification of injured myocardium by ischemia or inflammation. FDG-PET/MRI might aid to answer the clinical tasks according to the structure, current function and possibilities to improve the function in ischemic heart disease or to display the extent or activity of myocardial inflammation in sarcoidosis. The tight coupling between metabolism, perfusion and contractile function offers an opportunity for the simultaneous assessment of cardiac performance using one imaging modality.

  12. Effect of ethanol and the catalase inhibitor aminotriazole on lipid peroxidation in the rat myocardium

    International Nuclear Information System (INIS)

    Panchenko, L.F.; Pirozhkov, S.V.; Popova, S.V.; Antonenkov, V.D.

    1987-01-01

    The authors study the effect of chronic administration of ethanol and aminotriazole on the level of lipid peroxidation in the ray myocardium. The action of natural and artificial antioxidants on alcohol-induced lipid peroxidation also was studied. To determine the level of chemiluminescence, 1 ml of a sample of nuclear free homogenate or of the total fraction of particles was introduced for radioactivity measurement. After incubation the spontaneous weak luminescence was measured

  13. Automatic segmentation of myocardium at risk from contrast enhanced SSFP CMR: validation against expert readers and SPECT

    International Nuclear Information System (INIS)

    Tufvesson, Jane; Carlsson, Marcus; Aletras, Anthony H.; Engblom, Henrik; Deux, Jean-François; Koul, Sasha; Sörensson, Peder; Pernow, John; Atar, Dan; Erlinge, David; Arheden, Håkan; Heiberg, Einar

    2016-01-01

    Efficacy of reperfusion therapy can be assessed as myocardial salvage index (MSI) by determining the size of myocardium at risk (MaR) and myocardial infarction (MI), (MSI = 1-MI/MaR). Cardiovascular magnetic resonance (CMR) can be used to assess MI by late gadolinium enhancement (LGE) and MaR by either T2-weighted imaging or contrast enhanced SSFP (CE-SSFP). Automatic segmentation algorithms have been developed and validated for MI by LGE as well as for MaR by T2-weighted imaging. There are, however, no algorithms available for CE-SSFP. Therefore, the aim of this study was to develop and validate automatic segmentation of MaR in CE-SSFP. The automatic algorithm applies surface coil intensity correction and classifies myocardial intensities by Expectation Maximization to define a MaR region based on a priori regional criteria, and infarct region from LGE. Automatic segmentation was validated against manual delineation by expert readers in 183 patients with reperfused acute MI from two multi-center randomized clinical trials (RCT) (CHILL-MI and MITOCARE) and against myocardial perfusion SPECT in an additional set (n = 16). Endocardial and epicardial borders were manually delineated at end-diastole and end-systole. Manual delineation of MaR was used as reference and inter-observer variability was assessed for both manual delineation and automatic segmentation of MaR in a subset of patients (n = 15). MaR was expressed as percent of left ventricular mass (%LVM) and analyzed by bias (mean ± standard deviation). Regional agreement was analyzed by Dice Similarity Coefficient (DSC) (mean ± standard deviation). MaR assessed by manual and automatic segmentation were 36 ± 10 % and 37 ± 11 %LVM respectively with bias 1 ± 6 %LVM and regional agreement DSC 0.85 ± 0.08 (n = 183). MaR assessed by SPECT and CE-SSFP automatic segmentation were 27 ± 10 %LVM and 29 ± 7 %LVM respectively with bias 2 ± 7 %LVM. Inter-observer variability was 0 ± 3 %LVM for manual delineation and

  14. Ischaemic tolerance in aged mouse myocardium: the role of adenosine and effects of A1 adenosine receptor overexpression

    Science.gov (United States)

    Headrick, John P; Willems, Laura; Ashton, Kevin J; Holmgren, Kirsten; Peart, Jason; Matherne, G Paul

    2003-01-01

    The genesis of the ischaemia intolerant phenotype in aged myocardium is poorly understood. We tested the hypothesis that impaired adenosine-mediated protection contributes to ischaemic intolerance, and examined whether this is countered by A1 adenosine receptor (A1AR) overexpression. Responses to 20 min ischaemia and 45 min reperfusion were assessed in perfused hearts from young (2–4 months) and moderately aged (16–18 months) mice. Post-ischaemic contractility was impaired by ageing with elevated ventricular diastolic (32 ± 2 vs. 18 ± 2 mmHg in young) and reduced developed (37 ± 3 vs. 83 ± 6 mmHg in young) pressures. Lactate dehydrogenase (LDH) loss was exaggerated (27 ± 2 vs. 16 ± 2 IU g−1in young) whereas the incidence of tachyarrhythmias was similar in young (15 ± 1 %) and aged hearts (16 ± 1 %). Functional analysis confirmed equipotent effects of 50 μm adenosine at A1 and A2 receptors in young and aged hearts. Nonetheless, while 50 μm adenosine improved diastolic (5 ± 1 mmHg) and developed pressures (134 ± 7 mmHg) and LDH loss (6 ± 2 IU g−1) in young hearts, it did not alter these variables in the aged group. Adenosine did attenuate arrhythmogenesis for both ages (to ∼10 %). In contrast to adenosine, 50 μm diazoxide reduced ischaemic damage and arrhythmogenesis for both ages. Contractile and anti-necrotic effects of adenosine were limited by 100 μm 5-hydroxydecanoate (5-HD) and 3 μm chelerythrine. Anti-arrhythmic effects were limited by 5-HD but not chelerythrine. Non-selective (100 μm 8-sulfophenyltheophylline) and A1-selective (150 nm 8-cyclopentyl-1,3-dipropylxanthine) adenosine receptor antagonism impaired ischaemic tolerance in young but not aged hearts. Quantitative real-time PCR and radioligand analysis indicated that impaired protection is unrelated to changes in A1AR mRNA transcription, or receptor density (∼8 fmol mg−1 protein in both age groups). However, A1AR overexpression improved tolerance for both ages, restoring

  15. Prophylactic implantable defibrillator in patients with arrhythmogenic right ventricular cardiomyopathy/dysplasia and no prior ventricular fibrillation or sustained ventricular tachycardia.

    LENUS (Irish Health Repository)

    Corrado, Domenico

    2010-09-21

    The role of implantable cardioverter-defibrillator (ICD) in patients with arrhythmogenic right ventricular cardiomyopathy\\/dysplasia and no prior ventricular fibrillation (VF) or sustained ventricular tachycardia is an unsolved issue.

  16. Myocardium scanning with 201TL-chloride in ischemic heart disease

    International Nuclear Information System (INIS)

    Shejretova, E.; Beloev, J.; Kaloyanova, A.; Trindev, P.

    1979-01-01

    Results of myocardial scanning with 210 TL-chloride in ischemic herart disease are repoorted. An avearge dose of 500 microcurie and antero-posterior or lateral projection scanning with coloured registration are recommended. The scintigraphic pattern of the normal myocardium and the pathological changes, manifested by reduced isotope fixation, depending on the severity of the damage, are described. The diffuse pathological changes in the myocardium in ischemic heart disease are manifested by diffuse hypofixation of the radionuclide. The focal lesions in ischemic heart disease were manifested by characteristic changes: the infarctions of the posterior wall show a relatively clear scanographic picture on antero-posterior projection, with cold or cool zones in the median sections of the myocardium picture. Infarctions of the anterior myocardial wall, depending on how sizable they are, on antero-posterior projection are seen to occupy the lateral and central parts of the heart muscle. In the left oblique projection the pathologic process is projected frontally and centrally. (A.B.)

  17. Genetic modification of stem cells for improved therapy of the infarcted myocardium.

    Science.gov (United States)

    Haider, Husnain Kh; Mustafa, Anique; Feng, Yuliang; Ashraf, Muhammad

    2011-10-03

    The conventional treatment modalities for ischemic heart disease only provide symptomatic relief to the patient without repairing and regenerating the damaged myocardium. Stem cell transplantation has emerged as a promising alternative therapeutic approach for cardiovascular diseases. Stem cells possess the potential of differentiation to adopt morphofunctional cardiac and vasculogenic phenotypes to repopulate the scar tissue and restore regional blood flow in the ischemic myocardium. These beneficial therapeutic effects make stem cell transplantation the method of choice for the treatment of ischemic heart disease. The efficacy of stem cell transplantation may be augmented by genetic manipulation of the cells prior to transplantation. Not only will insertion of therapeutic transgene(s) into the stem cells support the survival and differentiation of cells in the unfavorable microenvironment of the ischemic myocardium, but also the genetically manipulated stem cells will serve as a source of the transgene expression product in the heart for therapeutic benefits. We provide an overview of the extensively studied stem cell types for cardiac regeneration, the various methods in which these cells have been genetically manipulated and rationale of genetic modification of stem cells for use in regenerative cardiovascular therapeutics.

  18. Metabolic shifts in the myocardium in the long-term effect of atmospheric pollution on the body

    Energy Technology Data Exchange (ETDEWEB)

    Tsapok, P I; Turdakin, P G; Barkov, L V; Ovcharuk, I N; Protod' iakonova, T N

    1981-04-01

    Metabolic shifts in the myocardium under conditions of long-term exposure of the body to air pollution were studied in experiments on albino rats. Study of the content of protein, RNA, DNA, glycogen, ATP, lactic and pyruvic acids and the activity of lactate dehydrogenase and creatine kinase in the heart muscle allowed the conclusion that the glycolytic processes are intensified, the bioenergic processes are inhibited and the synthesis of protein and RNA are increased in the myocardium of the experimental animals.

  19. Importance of scintigraphy of the myocardium with Csup(99m)-Tc-pyrophosphate in the diagnosis of myocardial ischemia

    Energy Technology Data Exchange (ETDEWEB)

    Botnar' , V I; Dvoskina, I S [Inst. Kardiologii Vsesoyuznogo Kardiologicheskogo Nauchnogo Tsentra AN SSSR

    1983-10-01

    The following aspects of the method of scintigraphy of the myocardium with sup(99m)Tc-pyrophosphate as test sensitivity, possibility of estimating necrosis focus, prognostic importance of the method, scintigram dynamics in case of acute infarction, pyrophosphate accumulation in myocardial cells are considered. Advantages and prospects of the method for visualization of acute myocardium infarction focus and in cases of other pathological states are pointed out.

  20. Mutation in cultured mammalian cells

    International Nuclear Information System (INIS)

    Nakamura, N.; Okada, S.

    1982-01-01

    Mammalian cell cultures were exposed to gamma-rays at various dose rates. Dose-rate effects were observed in cultured somatic cells of the mouse for cell killing and mutations resistant to 6-thioguanine (TGsup(r)) and to methotrexate (MTXsup(r)). Linear quadratic model may be applied to cell killing and TGsup(r) mutations in some cases but can not explain the whole data. Results at low doses with far low dose-rate were not predictable from data at high doses with acute or chronic irradiation. Radioprotective effects of dimethyl sulfoxide were seen only after acute exposure but not after chronic one, suggesting that damages by indirect action of radiations may be potentially reparable by cells. TGsup(r) mutations seem to contain gross structural changes whereas MTXsup(r) ones may have smaller alterations. (Namekawa, K.)

  1. Interaction theory of mammalian mitochondria.

    Science.gov (United States)

    Nakada, K; Inoue, K; Hayashi, J

    2001-11-09

    We generated mice with deletion mutant mtDNA by its introduction from somatic cells into mouse zygotes. Expressions of disease phenotypes are limited to tissues expressing mitochondrial dysfunction. Considering that all these mice share the same nuclear background, these observations suggest that accumulation of the mutant mtDNA and resultant expressions of mitochondrial dysfunction are responsible for expression of disease phenotypes. On the other hand, mitochondrial dysfunction and expression of clinical abnormalities were not observed until the mutant mtDNA accumulated predominantly. This protection is due to the presence of extensive and continuous interaction between exogenous mitochondria from cybrids and recipient mitochondria from embryos. Thus, we would like to propose a new hypothesis on mitochondrial biogenesis, interaction theory of mitochondria: mammalian mitochondria exchange genetic contents, and thus lost the individuality and function as a single dynamic cellular unit. Copyright 2001 Academic Press.

  2. Producing Newborn Synchronous Mammalian Cells

    Science.gov (United States)

    Gonda, Steve R.; Helmstetter, Charles E.; Thornton, Maureen

    2008-01-01

    A method and bioreactor for the continuous production of synchronous (same age) population of mammalian cells have been invented. The invention involves the attachment and growth of cells on an adhesive-coated porous membrane immersed in a perfused liquid culture medium in a microgravity analog bioreactor. When cells attach to the surface divide, newborn cells are released into the flowing culture medium. The released cells, consisting of a uniform population of synchronous cells are then collected from the effluent culture medium. This invention could be of interest to researchers investigating the effects of the geneotoxic effects of the space environment (microgravity, radiation, chemicals, gases) and to pharmaceutical and biotechnology companies involved in research on aging and cancer, and in new drug development and testing.

  3. Cardiac Magnetic Resonance Feature Tracking Biventricular Two-Dimensional and Three-Dimensional Strains to Evaluate Ventricular Function in Children After Repaired Tetralogy of Fallot as Compared with Healthy Children.

    Science.gov (United States)

    Berganza, Fernando M; de Alba, Cesar Gonzalez; Özcelik, Nazire; Adebo, Dilachew

    2017-03-01

    ventricular end-diastolic volume (P ≤ 0.0001) was noted. We found a strong correlation between left ventricular circumferential 3D strain and indexed right ventricular end-diastolic volume, as well as a strong correlation between left ventricular longitudinal 2D strain and right ventricular ejection fraction. Circumferential 3D strain may be a suitable tool to detect early abnormalities of ventricular myocardium even before the ejection fraction becomes compromised. Large-scale prospective studies are recommended.

  4. Mammalian gastrointestinal parasites in rainforest remnants

    Indian Academy of Sciences (India)

    Here, we studied the gastrointestinal parasites of nonhuman mammalian hosts living in 10 rainforest patches of the Anamalai Tiger Reserve, India. We examined 349 faecal samples of 17 mammalian species and successfully identified 24 gastroin-testinal parasite taxa including 1 protozoan, 2 trematode, 3 cestode and 18 ...

  5. Photodynamic Inactivation of Mammalian Viruses and Bacteriophages

    Directory of Open Access Journals (Sweden)

    Liliana Costa

    2012-06-01

    Full Text Available Photodynamic inactivation (PDI has been used to inactivate microorganisms through the use of photosensitizers. The inactivation of mammalian viruses and bacteriophages by photosensitization has been applied with success since the first decades of the last century. Due to the fact that mammalian viruses are known to pose a threat to public health and that bacteriophages are frequently used as models of mammalian viruses, it is important to know and understand the mechanisms and photodynamic procedures involved in their photoinactivation. The aim of this review is to (i summarize the main approaches developed until now for the photodynamic inactivation of bacteriophages and mammalian viruses and, (ii discuss and compare the present state of the art of mammalian viruses PDI with phage photoinactivation, with special focus on the most relevant mechanisms, molecular targets and factors affecting the viral inactivation process.

  6. Right ventricular function in patients with ischemic heart disease

    International Nuclear Information System (INIS)

    Araki, Haruo; Hisano, Ryuichi; Nagata, Yoshiyuki; Caglar, N.; Nakamura, Motoomi

    1985-01-01

    Thirty-five patients with ischemic heart disease (IHD) and 10 normal subjects were studied. Right and left ventricular ejecction fractions (EF) were determined using equilibrium radionuclide ventriculography with technetium-99m. Furthermore, abnormal motion of the right ventricular septal wall was obtained by cardiac cathetelization, and its relation to the right ventricular EF was examined. In IHD patients with anterior myocardial infarction, left ventricular EF decreased, but right ventricular EF was normal. This suggested that left ventricular dysfunction does not always have an effect on right ventricular function. Right ventricular EF was normal even when akinesis or dyskinesis was present in the ventricular septul, suggesting that abnormal motion of the ventricular septal wall has no significantly stimulant effect on right ventricular function. A decreased right ventricular EF was likely to occur only when the right ventricular free wall became ischemic or necrotic simultaneously with occurrence of posterior myocardial infarction. (Namekawa, K.)

  7. Transient severe left ventricular dysfunction following percutaneous patent ductus arteriosus closure in an adult with bicuspid aortic valve: A case report.

    Science.gov (United States)

    Hwang, Hui-Jeong; Yoon, Kyung Lim; Sohn, Il Suk

    2016-03-01

    The present study reported the case of a 60-year-old female with patent ductus arteriosus (PDA) and a bicuspid aortic valve, who presented with transient severe left ventricular (LV) dysfunction following percutaneous closure of PDA, as identified by speckle tracking analysis. Transient LV dysfunction following PDA closure has previously been reported; however, severe LV dysfunction is rare. In the present case, the combination of a large PDA size, large amount of shunting, LV remodeling and bicuspid aortic valve may have induced serious deterioration of LV function following PDA closure. Furthermore, speckle-tracking echocardiography may be useful in the estimation of functional alterations in the myocardium of the LV following PDA closure. The observations detailed in the present study may improve the understanding of the pathophysiology and myocardial patterns of transient left ventricular dysfunction following PDA closure in adult humans.

  8. Arrhythmogenic Right Ventricular Cardiomyopathy in an Endurance Athlete Presenting with Ventricular Tachycardia and Normal Right Ventricular Function.

    Science.gov (United States)

    Hedley, Jeffrey S; Al Mheid, Ibhar; Alikhani, Zoubin; Pernetz, Maria A; Kim, Jonathan H

    2017-08-01

    Arrhythmogenic right ventricular cardiomyopathy, a genetically inherited disease that results in fibrofatty replacement of normal cardiac myocytes, has been associated with sudden cardiac death in athletes. Long-term participation in endurance exercise hastens the development of both the arrhythmic and structural arrhythmogenic right ventricular cardiomyopathy phenotypes. We describe the unusual case of a 34-year-old, symptomatic, female endurance athlete who had arrhythmogenic right ventricular cardiomyopathy in the presence of a structurally normal right ventricle. Clinicians should be aware of this infrequent presentation when evaluating athletic patients who have ventricular arrhythmias and normal findings on cardiac imaging studies.

  9. Does reducing unnecessary right ventricular pacing improve sympathetic activity and innervation of heart in sinus node disease patients? MVP and SafeR study.

    Science.gov (United States)

    Miyamoto, Mihoko; Kimura, Yuichiro; Hosoda, Junya; Matsumoto, Katsumi; Matsushita, Kohei; Ishikawa, Toshiyuki; Umemura, Satoshi

    2012-01-01

    Ventricular desynchronization imposed by ventricular pacing causes regional disturbances of adrenergic innervation in the left ventricular myocardium and increases the risk of heart failure and atrial fibrillation (AF) in patients with sinus node disease (SND). As a result, decreased iodine-123 metaiodobenzylguanidine (I-(123 )MIBG) uptake occurs in patients with an implanted permanent pacemaker. Fourteen SND patients with an implanted pacemaker equipped with an algorithm for reducing unnecessary right ventricular pacing (RURVP) were enrolled. Pacemakers were programmed to RURVP mode for the first 12 weeks, and then reprogrammed to DDD for the last 12 weeks. At the end of each mode, data on cumulative percent ventricular pacing (%Vp), atrial high rate episodes (%AHR), I-(123 )MIBG myocardial scintigraphy, brain natriuretic peptide (BNP), human atrial natriuretic peptide (hANP), and myocardial damage indices typified by troponin T and C-reactive protein (CRP) were collected. %Vp was lower in RURVP than in DDD (0.2% versus 95.7%, P = 0.00098). BNP, hANP, troponin T, and CRP did not differ significantly between the pacing modes. However, I-(123 )MIBG findings of patients with full ventricular pacing in DDD improved in RURVP. In contrast, among patients without full ventricular pacing in DDD, their I-(123 )MIBG findings did not differ significantly between the pacing modes. In SND patients with normal cardiac function and intact atrioventricular conduction, the reduction of %Vp in RURVP was due to the reduction of ineffective pacing and fusion pacing in DDD. Therefore, these 2 types of pacing do not affect cardiac pump function.

  10. Surgical ablation of ventricular tachycardia secondary to congenital ventricular septal aneurysm.

    Science.gov (United States)

    Graffigna, A; Minzioni, G; Ressia, L; Vigano, M

    1994-04-01

    Three patients underwent surgical ablation for ventricular tachycardia resulting from an aneurysm of the membranous portion of the ventricular septum. Two patients had a definite history of cardiac murmur during infancy, and one of them was found at the time of operation to have a left-to-right shunt through the apex of the aneurysm. The earliest ventricular activation sites were located around the neck of the aneurysm and were ablated in 1 patient by encircling the endocardial ventriculotomy and by cryoablation in the remaining 2. After focus resection had been completed, aneurysm resection and ventricular septal reconstruction were performed. All patients were alive and free of ventricular tachycardia and did not need medication as of 61, 66, and 88 months postoperatively. Spontaneous closure of a ventricular septal defect may lead to the formation of an aneurysm in the ventricular septum that may sustain ventricular tachycardias. Such arrhythmias can be effectively treated using electrically guided surgical techniques.

  11. Functional and structural regeneration in the axolotl heart (Ambystoma mexicanum) after partial ventricular amputation.

    Science.gov (United States)

    Cano-Martínez, Agustina; Vargas-González, Alvaro; Guarner-Lans, Verónica; Prado-Zayago, Esteban; León-Oleda, Martha; Nieto-Lima, Betzabé

    2010-01-01

    "In the present study we evaluated the effect of partial ventricular amputation (PVA) in the heart of the adult urodele amphibian (Ambystoma mexicanum) in vivo on spontaneous heart contractile activity recorded in vitro in association to the structural recovery at one, five, 30 and 90 days after injury. One day after PVA, ventricular-tension (VT) (16 ± 3%), atrium-tension (AT) (46 ± 4%) and heart rate (HR) (58+10%) resulted lower in comparison to control hearts. On days five, 30 and 90 after damage, values achieved a 61 ± 5, 93 ± 3, and 98 ± 5% (VT), 60 ± 4, 96 ± 3 and 99 ± 5% (AT) and 74 ± 5, 84 ± 10 and 95 ± 10% (HR) of the control values, respectively. Associated to contractile activity recovery we corroborated a gradual tissue restoration by cardiomyocyte proliferation. Our results represent the first quantitative evidence about the recovery of heart of A. mexicanum restores its functional capacity concomitantly to the structural recovery of the myocardium by proliferation of cardiomyocytes after PVA. These properties make the heart of A. mexicanum a potential model to study the mechanisms underlying heart regeneration in adult vertebrates in vivo.

  12. Evaluation of Subclinical Left Ventricular Systolic Dysfunction in Chronic Asymptomatic Alcoholics by Speckle Tracking Echocardiography

    Directory of Open Access Journals (Sweden)

    Murathan Kucuk

    2017-01-01

    Full Text Available By using two-dimensional speckle tracking echocardiography, we aimed to investigate the structural and functional changes on myocardium in chronic asymptomatic alcoholics without any cardiovascular disease. Forty-one consecutive asymptomatic male alcoholics who were admitted to the outpatient alcoholism unit and 30 age matched healthy male volunteers selected as the control group were enrolled in the study. The study group were investigated by using standard two-dimensional echocardiography and speckle tracking echocardiography. The left ventricular (LV global longitudinal strain and LV global circumferential strain were significantly lower in alcoholics when compared with control subjects. There was no difference in global radial strain between the two groups. To demonstrate the effect of total life time dose of ethanol (TLDE on echocardiographic abnormalities, we assessed the correlation analysis. There was a nonsignificant weak correlation between global LV circumferential strain and TLDE (r=0.27, p=0.083. Speckle tracking echocardiography derived left ventricular systolic function was impaired in chronic alcoholic patients when compared with healthy controls.

  13. Effects of tacrolimus on action potential configuration and transmembrane ion currents in canine ventricular cells.

    Science.gov (United States)

    Szabó, László; Szentandrássy, Norbert; Kistamás, Kornél; Hegyi, Bence; Ruzsnavszky, Ferenc; Váczi, Krisztina; Horváth, Balázs; Magyar, János; Bányász, Tamás; Pál, Balázs; Nánási, Péter P

    2013-03-01

    Tacrolimus is a commonly used immunosuppressive agent which causes cardiovascular complications, e.g., hypertension and hypertrophic cardiomyopathy. In spite of it, there is little information on the cellular cardiac effects of the immunosuppressive agent tacrolimus in larger mammals. In the present study, therefore, the concentration-dependent effects of tacrolimus on action potential morphology and the underlying ion currents were studied in canine ventricular cardiomyocytes. Standard microelectrode, conventional whole cell patch clamp, and action potential voltage clamp techniques were applied in myocytes enzymatically dispersed from canine ventricular myocardium. Tacrolimus (3-30 μM) caused a concentration-dependent reduction of maximum velocity of depolarization and repolarization, action potential amplitude, phase-1 repolarization, action potential duration, and plateau potential, while no significant change in the resting membrane potential was observed. Conventional voltage clamp experiments revealed that tacrolimus concentrations ≥3 μM blocked a variety of ion currents, including I(Ca), I(to), I(K1), I(Kr), and I(Ks). Similar results were obtained under action potential voltage clamp conditions. These effects of tacrolimus developed rapidly and were fully reversible upon washout. The blockade of inward currents with the concomitant shortening of action potential duration in canine myocytes is the opposite of those observed previously with tacrolimus in small rodents. It is concluded that although tacrolimus blocks several ion channels at higher concentrations, there is no risk of direct interaction with cardiac ion channels when applying tacrolimus in therapeutic concentrations.

  14. Electrocardiographic features suggestive of a left. ventricular ...

    African Journals Online (AJOL)

    1983-01-01

    Jan 1, 1983 ... indirectly by the transmission of the high energy of the bullet to the nearby myocardium.l-4 This 'shock wave' may extend up to a distance of 20 times ... His history negated any cardiovascular impairment, angina or limitation in ...

  15. Fetal stem cells in combined treatment of chronic heart failure and their effect on morphofunctional parameters of the left ventricle myocardium and cognitive functions

    Directory of Open Access Journals (Sweden)

    Klunnyk MO

    2014-08-01

    group. In both groups, reactive anxiety levels dropped after month 3 upon FSCT. FSCT resulted in statistically significant improvements in the contractile activity of the left ventricular myocardium, in cognitive functions, and in the emotional state of CHF patients. Conclusion: The evidence for significant improvements in the contractile function of the left ventricle myocardium, as well as in patients' cognitive and emotional states, was observed in CHF patients after combined treatment with FSC. Keywords: heart failure, cognitive, emotional impairment, fetal stem cells, left ventricle remodeling

  16. A New Class III Antiarrhythmic Drug Niferidil Prolongs Action Potentials in Guinea Pig Atrial Myocardium via Inhibition of Rapid Delayed Rectifier.

    Science.gov (United States)

    Abramochkin, Denis V; Kuzmin, Vladislav S; Rosenshtraukh, Leonid V

    2017-12-01

    A new class III antiarrhythmic drug niferidil (RG-2) has been introduced as a highly effective therapy for cases of persistent atrial fibrillation, but ionic mechanisms of its action are poorly understood. In the present study, the effects of niferidil on action potential (AP) waveform and potassium currents responsible for AP repolarization were investigated in guinea pig atrial myocardium. APs were recorded with sharp glass microelectrodes in multicellular atrial preparations. Whole-cell patch-clamp technique was used to measure K + currents in isolated myocytes. In multicellular atrial preparations, 10 -8  M niferidil effectively prolonged APs by 15.2 ± 2.8% at 90% repolarization level. However, even the highest tested concentrations, 10 -6  M and 10 -5  M failed to prolong APs more than 32.5% of control duration. The estimated concentration of niferedil for half-maximal AP prolongation was 1.13 × 10 -8  M. Among the potassium currents responsible for AP repolarization phase, I K1 was found to be almost insensitive to niferidil. However, another inward rectifier, I KACh , was effectively suppressed by micromolar concentrations of niferidil with IC 50  = 9.2 × 10 -6  M. I KATP was much less sensitive to the drug with IC 50  = 2.26 × 10 -4  M. The slow component of delayed rectifier, I Ks , also demonstrated low sensitivity to niferidil-the highest used concentration, 10 -4  M, decreased peak I Ks density to 46.2 ± 5.5% of control. Unlike I Ks , the rapid component of delayed rectifier, I Kr , appeared to be extremely sensitive to niferidil. The IC 50 was 1.26 × 10 -9  M. I Kr measured in ventricular myocytes was found to be less sensitive to niferidil with IC 50  = 3.82 × 10 -8  M. Niferidil prolongs APs in guinea pig atrial myocardium via inhibition of I Kr .

  17. Effects of high-intensity interval versus continuous moderate-intensity aerobic exercise on apoptosis, oxidative stress and metabolism of the infarcted myocardium in a rat model.

    Science.gov (United States)

    Lu, Kai; Wang, Li; Wang, Changying; Yang, Yuan; Hu, Dayi; Ding, Rongjing

    2015-08-01

    The optimal aerobic exercise training (AET) protocol for patients following myocardial infarction (MI) has remained under debate. The present study therefore aimed to compare the effects of continuous moderate-intensity training (CMT) and high-intensity interval training (HIT) on cardiac functional recovery, and to investigate the potential associated mechanisms in a post-MI rat model. Female Sprague Dawley rats (8-10 weeks old) undergoing MI or sham surgery were subsequently submitted to CMT or HIT, or kept sedentary for eight weeks. Prior to and following AET, echocardiographic parameters and exercise capacity of the rats were measured. Western blotting was used to evaluate the levels of apoptosis and associated signaling pathway protein expression. The concentrations of biomarkers of oxidative stress were also determined by ELISA assay. Messenger (m)RNA levels and activity of the key enzymes for glycolysis and fatty acid oxidation, as well as the rate of adenosine triphosphate (ATP) synthesis, were also measured. Compared with the MI group, exercise capacity and cardiac function were significantly improved following AET, particularly following HIT. Left ventricular ejection fraction and fraction shortening were further improved in the MI-HIT group in comparison to that of the MI-CMT group. The two forms of AET almost equally attenuated apoptosis of the post-infarction myocardium. CMT and HIT also alleviated oxidative stress by decreasing the concentration of malondialdehyde and increasing the concentration of superoxide dismutase and glutathione peroxidase (GPx). In particular, HIT induced a greater increase in the concentration of GPx than that of CMT. AET, and HIT in particular, significantly increased the levels of mRNA and the maximal activity of phosphofructokinase-1 and carnitine palmitoyl transferase-1, as well as the maximal ratio of ATP synthesis. In addition, compared with the MI group, the expression of signaling proteins PI3K, Akt, p38mapk and AMPK

  18. [Intervention of systolic pressure and left ventricular hypertrophy in rats under cold stress].

    Science.gov (United States)

    Sun, C F; Wang, S G; Peng, Y G; Shi, Y; Du, Y P; Shi, G X; Wen, T; Wang, Y K; Su, H

    2016-06-20

    To investigate the effects of different drugs on systolic blood pressure (SBP) and left ventricular hypertrophy (LVH) in spontaneously hypertensive rats under cold stress. A total of 40 male spontaneously hypertensive rats aged 10 weeks (160~200 g) were given adaptive feeding for 7 days at a temperature of 20±1°C and then randomly divided into control group, cold stress group, metoprolol group, amlodipine group, and benazepril group, with 8 rats in each group. SBP, body weight, and heart rate were measured once a week. After the rats were sacrificed by exsanguination, left ventricular weight (LVW) was measured, and left ventricular weight index (LVWI; mg/g) was calculated. Radioimmunoassay was used to measure the concentrations of endothelin-1 (ET-1) and angiotensin-II (Ang-II) in plasma and myocardium, and the chemical method was used to measure the concentrations of nitric oxide (NO) in plasma and myocardium. RT-PCR was used to measure the mRNA expression of endothelin-A receptor. Compared with the cold stress group, all medication groups showed significant reductions in SBP since week 5 (Pcold stress group showed a significant increase in LVWI compared with the control group (3.38±0.27 mg/g vs 2.89±0.19 mg/g, Pcold stress group (2.98±0.28 mg/g vs 3.38±0.27 mg/g, Pcold stress group showed a significant reduction in plasma NO concentration compared with the control group (104.9±19.5 μmol/L vs 129.3±17.8 μmol/L, Pcold stress group, all the medication groups showed significant increases in blood NO concentration (Pcold stress group showed a significant increase in myocardial ET-1 concentration compared with the control group (6.3±1.5 pg/100 mg vs 4.5±1.9 pg/100 mg, Pcold stress group, the amlodipine group showed a significant reduction in myocardial ET-1 concentration (4.4±1.0 pg/100 mg vs 6.3±1.5 pg/100 mg, Pcold stress group had significantly higher mRNA expression of endothelin-A receptor than the control group (0.86±0.23 vs 0.45±0.16, Pcold

  19. Stop-gain mutations in PKP2 are associated with a later age of onset of arrhythmogenic right ventricular cardiomyopathy.

    Directory of Open Access Journals (Sweden)

    Mireia Alcalde

    Full Text Available BACKGROUND: Arrhythmogenic right ventricular cardiomyopathy (ARVC is a cardiac disease characterized by the presence of fibrofatty replacement of the right ventricular myocardium, which may cause ventricular arrhythmias and sudden cardiac death. Pathogenic mutations in several genes encoding mainly desmosomal proteins have been reported. Our aim is to perform genotype-phenotype correlations to establish the diagnostic value of genetics and to assess the role of mutation type in age-related penetrance in ARVC. METHODS AND RESULTS: Thirty unrelated Spanish patients underwent a complete clinical evaluation. They all were screened for PKP2, DSG2, DSC2, DSP, JUP and TMEM43 genes. A total of 70 relatives of four families were also studied. The 30 patients fulfilled definite disease diagnostic criteria. Genetic analysis revealed a pathogenic mutation in 19 patients (13 in PKP2, 3 in DSG2, 2 in DSP, and 1 in DSC2. Nine of these mutations created a truncated protein due to the generation of a stop codon. Familial assessment revealed 28 genetic carriers among family members. Stop-gain mutations were associated to a later age of onset of ARVC, without differences in the severity of the pathology. CONCLUSIONS: Familial genetic analysis helps to identify the cause responsible for the pathology. In discrepancy with previous studies, the presence of a truncating protein does not confer a worse severity. This information could suggest that truncating proteins may be compensated by the normal allele and that missense mutations may act as poison peptides.

  20. Neuromodulation therapy does not influence blood flow distribution or left-ventricular dynamics during acute myocardial ischemia.

    Science.gov (United States)

    Kingma, J G; Linderoth, B; Ardell, J L; Armour, J A; DeJongste, M J; Foreman, R D

    2001-08-13

    Electrical stimulation of the dorsal aspect of the upper thoracic spinal cord is used increasingly to treat patients with angina pectoris refractory to conventional therapeutic strategies. The purpose of this study was to determine whether spinal cord stimulation (SCS) in dogs affects regional myocardial blood flow and left-ventricular (LV) function before and during transient obstruction of the left anterior descending coronary artery (LAD). In anesthetized dogs, regional myocardial blood flow distribution was determined using radiolabeled microspheres and left-ventricular function was measured by impedance-derived pressure-volume loops. SCS was accomplished by stimulating the dorsal T1-T2 segments of the spinal cord using epidural bipolar electrodes at 90% of motor threshold (MT) (50 Hz, 0.2-ms duration). Effects of 5-min SCS were assessed under basal conditions and during 4-min occlusion of the LAD. SCS alone evoked no change in regional myocardial blood flow or cardiovascular indices. Transient LAD occlusion significantly diminished blood flow within ischemic, but not in non-ischemic myocardial tissue. Left ventricular pressure-volume loops were shifted rightward during LAD occlusion. Cardiac indices were altered similarly during LAD occlusion and concurrent SCS. SCS does not influence the distribution of blood flow within the non-ischemic or ischemic myocardium. Nor does it modify LV pressure-volume dynamics in the anesthetized experimental preparation.

  1. Observations of super early left ventricular remodeling experimental myocardial infarction

    International Nuclear Information System (INIS)

    Zhang, C.G.; Jin, J.H.; Zhao, X.B.; Kang, C.S.; Liang, F.Y.; Yin, Z.M.; Liu, G.F.; Li, S.J.; Li, X.F.; Hu, G.; Qin, D.Z.; Song, L.Z.

    2004-01-01

    , the animals were euthanized and their hearts were examined for pathology. SPECT reconstruction parameters: Filter; Butterworth; cutoff 0.35 and order 5: filtered backprojection. Images: short axis, horizontal and vertical long axis. Data analysis: Quantitative analysis: Quantitative Gated SPECT (QGS) software was used for calculating the end diastolic volume (EDV), end systolic volume (ESV) and ejection fraction (EF) Data from 16 animals was used. Qualitative analysis was used to assess shape, size of entire left ventricle, and wall motion which data was from 15 dogs. Echocardiography: HP5500 color Doppler ultrasonography diagnosis system with 12 MHz was used for echocardiography. EDV, ESV and EF were calculated by Simpson's method. Statistics analysis: SPSS statistics software was used for all quantitative data analysis. Results: A typical defect with complete absence of wall motion was found at the apex in all dogs (GA and GB) after LAD ligation, beginning with the first acquisition. Post-operatively, EDV and ESV significantly increased compared with pre-operation values. EF significantly decreased post-operatively. The table below shows quantitative data obtained at the earliest time after ligation. EDV and ESV continued to increase during the 6 hours post-operatively, while EF was just the opposite, decreasing with time. Using continuous gated myocardial imaging, reperfusion was found in 10 dogs (62.5%) on the apex area at 1-3 hours after the defect was originally visualized, when a thinning wall could be seen on the apex defect area. By visual analysis we found structural characteristics of left ventricular remodeling, including infarct expansion with thinning (14/15 animals), lengthening (15/15), regional enlargement (9/15) and distortion (11/15). We also found remodeling of non-infarcted myocardium, including thickening (12/15) and lengthening (13/15) as well as global distortion of shape (15/15) and global ventricular dilatation (14/15). Statistical analysis

  2. Radial glia in the proliferative ventricular zone of the embryonic and adult turtle, Trachemys scripta elegans.

    Science.gov (United States)

    Clinton, Brian K; Cunningham, Christopher L; Kriegstein, Arnold R; Noctor, Stephen C; Martínez-Cerdeño, Verónica

    2014-01-01

    To better understand the role of radial glial (RG) cells in the evolution of the mammalian cerebral cortex, we investigated the role of RG cells in the dorsal cortex and dorsal ventricular ridge of the turtle, Trachemys scripta elegans. Unlike mammals, the glial architecture of adult reptile consists mainly of ependymoradial glia, which share features with mammalian RG cells, and which may contribute to neurogenesis that continues throughout the lifespan of the turtle. To evaluate the morphology and proliferative capacity of ependymoradial glia (here referred to as RG cells) in the dorsal cortex of embryonic and adult turtle, we adapted the cortical electroporation technique, commonly used in rodents, to the turtle telencephalon. Here, we demonstrate the morphological and functional characteristics of RG cells in the developing turtle dorsal cortex. We show that cell division occurs both at the ventricle and away from the ventricle, that RG cells undergo division at the ventricle during neurogenic stages of development, and that mitotic Tbr2+ precursor cells, a hallmark of the mammalian SVZ, are present in the turtle cortex. In the adult turtle, we show that RG cells encompass a morphologically heterogeneous population, particularly in the subpallium where proliferation is most prevalent. One RG subtype is similar to RG cells in the developing mammalian cortex, while 2 other RG subtypes appear to be distinct from those seen in mammal. We propose that the different subtypes of RG cells in the adult turtle perform distinct functions.

  3. Dynamic MRI of ferumoxide-labeled bone mesenchmal stem cells after transplantation in infarcted myocardium

    International Nuclear Information System (INIS)

    Liu Qiong; Zhao Shihua; Lu Minjie; Jiang Shiliang; Yan Chaowu; Zhang Yan; Meng Liang; Tang Yue; Meng Xianmin; Wei Yingjie; Wang Qingzhi

    2009-01-01

    Objective: To investigate the ability of magnetic resonance imaging (MRI) in tracking magnetically labeled mesenchymal stem cells (MR-MSCs) in a swine myocardial infarction (MI) model. Methods: Adult Chinese mini-pigs (n=6) were subjected to open-chest experimental MI operation. Their autogeneic bone marrow-derived mesenchymal stem cells (MSCs) was cultured and doubly labeled with ferumoxides and DAPI. On the 14 th day after MSCs transplantation, the size and location of the myocardial infarction were assessed by using delayed-enhancement MRI (DE-MRI). Then the labeled MSCs were injected intramyocardially into peri-infarct zone and normal myocardium. At 24 hrs and 3 weeks after injection, the contrast and the volume of the MR-MSCs hypointense lesion from the MR images were acquired, and the contrast was determined using the difference in signal intensity between the hypointense and normal myocardium divided by signal intensity of the normal region. After humane euthanasia, the heart was excised and histology corresponding to MRI slices that demonstrated MR-MSCs lesions was performed. Repeated-measures ANOVA and a paired t test were used for comparison of the contrast and the volume of the MR-MSCs hypointense lesion at different time points. Comparisons between independent groups were performed with the standard Student t test. Results: The labeling efficiency of ferumoxides and DAPI was 100%. On the 14 th day after the MI operation, the average percentage of infracted myocardial area was (33.6±8.9)%. Twenty- four hours after MSCs transplantation, MSCs injection sites appeared as ovoid hypointensive lesions with sharp border on T 2 * images. At 24 h after injection, the signal contrast [(67.00±5.48)% vs (61.92±7.76)%,t=1.65, P=0.1158] and the size [(0.56±0.24) cm 2 vs (0.52±0.25) cm 2 , t=0.39, P=0.7044] of the lesions showed no statistical difference between the peri-infarct zone and the normal myocardium. At 3 weeks after injection, the signal contrast

  4. Right Ventricular Outflow Tract Tachycardia with Structural Abnormalities of the Right Ventricle and Left Ventricular Diverticulum

    Directory of Open Access Journals (Sweden)

    Bortolo Martini

    2015-01-01

    Full Text Available A 43-year-old woman presented to the emergency room with a sustained ventricular tachycardia (VT. ECG showed a QRS in left bundle branch block morphology with inferior axis. Echocardiography, ventricular angiography, and cardiac magnetic resonance imaging (CMRI revealed a normal right ventricle and a left ventricular diverticulum. Electrophysiology studies with epicardial voltage mapping identified a large fibrotic area in the inferolateral layer of the right ventricular wall and a small area of fibrotic tissue at the anterior right ventricular outflow tract. VT ablation was successfully performed with combined epicardial and endocardial approaches.

  5. Clinical assessment of the effect of digital filtering on the detection of ventricular late potentials

    Directory of Open Access Journals (Sweden)

    P.R. Benchimol-Barbosa

    2002-11-01

    Full Text Available Ventricular late potentials are low-amplitude signals originating from damaged myocardium and detected on the body surface by ECG filtering and averaging. Digital filters present in commercial equipment may interfere with the ability of arrhythmia stratification. We compared 40-Hz BiSpec (BI and classical 40- to 250-Hz band-pass Butterworth bidirectional (BD filters in terms of impact on time domain variables and diagnostic properties. In a transverse retrospective age-adjusted case-control study, 221 subjects with sinus rhythm without bundle branch block were divided into three groups after signal-averaged ECG acquisition: GI (N = 40, clinically normal controls, GII (N = 158, subjects with coronary heart disease without sustained monomorphic ventricular tachycardia (SMVT, and GIII (N = 23, subjects with heart disease and documented SMVT. Conventional variables analyzed from vector magnitude data after averaging to 0.3 µV final noise were obtained by application of each filter to the averaged signal, and evaluated in pairs by numerical comparison and by diagnostic agreement assessment, using conventional and optimized thresholds of normality. Significant differences were found between BI and BD variables in all groups, with diagnostic results showing significant disagreement between both filters [kappa value of 0.61 (P<0.05 for GII and 0.31 for GIII (P = NS]. Sensitivity for SMVT was lower with BI than with BD (65.2 vs 91.3%, respectively, P<0.05. Filters provided significantly different numerical and diagnostic results and the BI filter showed only limited clinical application to risk stratification of ventricular arrhythmia.

  6. Effect of well-controlled gestational diabetes on left ventricular diastolic dysfunction in neonates.

    Science.gov (United States)

    Ghandi, Yazdan; Habibi, Danial; Nasri, Khadijeh; Alinejad, Saeed; Taherahmad, Hassan; Arjmand Shabestari, Ali; Nematinejad, Ali

    2018-06-17

    There are some evidences supporting the relation between gestational diabetes mellitus (GDM) and diastolic dysfunction. The aim of our study was to investigate the effect of well-controlled GDM on morphological and functional myocardium. We designed a prospective cross-sectional study to evaluate left ventricular (LV) diastolic function of 60 neonates born from mothers with well-controlled GDM (case group) on days of 3-5 after birth. The infants of diabetic mothers (IDM) group were divided into two groups: diabetic mothers treated only with diet (class A) and group of mothers on medical therapy by insulin or metformin (class B). Traditional echocardiography and pulsed-wave Doppler (PWD), tissue Doppler imaging (TDI) were performed for all the neonates. The study group consisted of 60 neonates as males (M) = 32, (0.53%) and females (F) = 28, (0.46%). Using M-mode echocardiography, interventricular septum thickness (IVS), and LV mass were significantly higher in IDM than control group (p = .0001). The PWD showed both a significantly more peak mitral flow at early diastolic wave (E) and an early filling deceleration time (E-DT) (p = .0001). Tissue Doppler echocardiography parameters A' (cm/s) (p = .0001), E' (cm/s) (p = .002), and E'/A' ratio (p = .0001), left ventricular myocardial performance index (LVMPI), and isovolumetric relaxation time (IVRT) were outstandingly different between the two groups (p = .0001, respectively). Evaluating the GDM group mothers of class A and class B, no significant difference was noted in PWD or TDI parameters compared with the healthy ones. It seems that neonates of mothers with well-controlled GDM are still at increased risk of cardiac hypertrophy, subclinical diastolic dysfunction, and impaired left ventricular relaxation. This can be interpreted that focusing only on glycemic control is not enough to prevent cardiac dysfunction.

  7. Sustained nonoxidative glucose utilization and depletion of glycogen in reperfused canine myocardium

    International Nuclear Information System (INIS)

    Schwaiger, M.; Neese, R.A.; Araujo, L.

    1989-01-01

    Ischemically injured reperfused myocardium is characterized by increased 18F-fluorodeoxyglucose uptake as demonstrated by positron emission tomography. To elucidate the metabolic fate of exogenous glucose entering reperfused myocardium, D-[6-14C] glucose and L-[U-13C] lactate were used to determine glucose uptake, glucose oxidation and the contribution of exogenous glucose to lactate production. The pathologic model under investigation consisted of a 3 h balloon occlusion of the left anterior descending coronary artery followed by 24 h of reperfusion in canine myocardium. The extent and severity of myocardial injury after the ischemia and reperfusion were assessed by histochemical evaluation (triphenyltetrazolium chloride and periodic acid-Schiff stains). Thirteen intervention and four control dogs were studied. The glucose uptake in the occluded/reperfused area was significantly enhanced compared with that in control dogs (0.40 +/- 0.14 versus 0.15 +/- 0.10 mumol/ml, respectively). In addition, a significantly greater portion of the glucose extracted immediately entered glycolysis in the intervention group (75%) than in the control dogs (33%). The activity of the nonoxidative glycolytic pathway was markedly increased in the ischemically injured reperfused area, as evidenced by the four times greater lactate release in this area compared with the control value. The dual carbon-labeled isotopes showed that 57% of the exogenous glucose entering glycolysis was being converted to lactate. Exogenous glucose contributed to greater than 90% of the observed lactate production. This finding was confirmed by the histochemical finding of sustained glycogen depletion in the occlusion/reperfusion area. The average area of glycogen depletion (37%) significantly exceeded the average area of necrosis

  8. Metabolic syndrome impairs notch signaling and promotes apoptosis in chronically ischemic myocardium.

    Science.gov (United States)

    Elmadhun, Nassrene Y; Sabe, Ashraf A; Lassaletta, Antonio D; Chu, Louis M; Kondra, Katelyn; Sturek, Michael; Sellke, Frank W

    2014-09-01

    Impaired angiogenesis is a known consequence of metabolic syndrome (MetS); however, the mechanism is not fully understood. Recent studies have shown that the notch signaling pathway is an integral component of cardiac angiogenesis. We tested, in a clinically relevant swine model, the effects of MetS on notch and apoptosis signaling in chronically ischemic myocardium. Ossabaw swine were fed either a regular diet (control [CTL], n = 8) or a high-cholesterol diet (MetS, n = 8) to induce MetS. An ameroid constrictor was placed to induce chronic myocardial ischemia. Eleven weeks later, the wine underwent cardiac harvest of the ischemic myocardium. Downregulation of pro-angiogenesis proteins notch2, notch4, jagged2, angiopoietin 1, and endothelial nitric oxide synthase were found in the MetS group compared with the CTL group. Also, upregulation of pro-apoptosis protein caspase 8 and downregulation of anti-angiogenesis protein phosphorylated forkhead box transcription factor 03 and pro-survival proteins phosphorylated P38 and heat shock protein 90 were present in the MetS group. Cell death was increased in the MetS group compared with the CTL group. Both CTL and MetS groups had a similar arteriolar count and capillary density, and notch3 and jagged1 were both similarly concentrated in the smooth muscle wall. MetS in chronic myocardial ischemia significantly impairs notch signaling by downregulating notch receptors, ligands, and pro-angiogenesis proteins. MetS also increases apoptosis signaling, decreases survival signaling, and increases cell death in chronically ischemic myocardium. Although short-term angiogenesis appears unaffected in this model of early MetS, the molecular signals for angiogenesis are impaired, suggesting that inhibition of notch signaling might underlie the decreased angiogenesis in later stages of MetS. Copyright © 2014 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.

  9. Kinetics of thallium-201 in reperfused canine myocardium after coronary artery occlusion

    International Nuclear Information System (INIS)

    Okada, R.D.

    1984-01-01

    To study the kinetics of thallium-201 in nonsalvaged acutely infarcted myocardium and salvaged myocardium, the tracer was administered after experimental left anterior descending coronary artery reperfusion 2 hours after occlusion. In 19 dogs, thallium activity was then monitored for 4 hours in the reperfused anterior wall and normal posterior wall using miniature cadmium telluride radiation detectors. After sacrifice, 13 of the dogs were found to have an infarcted anterior wall by triphenyltetrazolium-chloride staining. In these dogs, mean (+/- standard deviation) fractional 4 hour thallium clearance was 0.33 +/- 0.08 for the infarct zone and 0.15 +/- 0.06 for the normal control zone (p less than 0.001). When computer-modeled, the clearance curve from the infarct zone was biexponential. The second exponential clearance curve from the infarct zone began 19.1 +/- 3.2 minutes after tracer administration, and was indistinguishable from the monoexponential clearance curve from the normal control zone. Thallium clearance from the blood pool was triexponential, the final exponential clearance curve being indistinguishable from the normal control zone clearance curve. Six dogs were found to have a salvaged noninfarcted anterior wall by triphenyltetrazolium-chloride staining. In these dogs, mean fractional 4 hour thallium clearance was 0.20 +/- 0.07 for the reperfused zone, and 0.19 +/- 0.08 for the normal control zone (p . NS). When computer-modeled, clearance curves for the reperfused and control zones were monoexponential. The monoexponential clearance curve for the salvaged reperfused zone was indistinguishable from the monoexponential clearance curve for normal myocardium

  10. Analysis of immune cell populations in atrial myocardium of patients with atrial fibrillation or sinus rhythm.

    Directory of Open Access Journals (Sweden)

    Natalia Smorodinova

    Full Text Available Atrial fibrillation (AF is the most common arrhythmia and despite obvious clinical importance remains its pathogenesis only partially explained. A relation between inflammation and AF has been suggested by findings of increased inflammatory markers in AF patients.The goal of this study was to characterize morphologically and functionally CD45-positive inflammatory cell populations in atrial myocardium of patients with AF as compared to sinus rhythm (SR.We examined 46 subjects (19 with AF, and 27 in SR undergoing coronary bypass or valve surgery. Peroperative bioptic samples of the left and the right atrial tissue were examined using immunohistochemistry.The number of CD3+ T-lymphocytes and CD68-KP1+ cells were elevated in the left atrial myocardium of patients with AF compared to those in SR. Immune cell infiltration of LA was related to the rhythm, but not to age, body size, LA size, mitral regurgitation grade, type of surgery, systemic markers of inflammation or presence of diabetes or hypertension. Most of CD68-KP1+ cells corresponded to dendritic cell population based on their morphology and immunoreactivity for DC-SIGN. The numbers of mast cells and CD20+ B-lymphocytes did not differ between AF and SR patients. No foci of inflammation were detected in any sample.An immunohistochemical analysis of samples from patients undergoing open heart surgery showed moderate and site-specific increase of inflammatory cells in the atrial myocardium of patients with AF compared to those in SR, with prevailing population of monocyte-macrophage lineage. These cells and their cytokine products may play a role in atrial remodeling and AF persistence.

  11. Mammalian synthetic biology: emerging medical applications.

    Science.gov (United States)

    Kis, Zoltán; Pereira, Hugo Sant'Ana; Homma, Takayuki; Pedrigi, Ryan M; Krams, Rob

    2015-05-06

    In this review, we discuss new emerging medical applications of the rapidly evolving field of mammalian synthetic biology. We start with simple mammalian synthetic biological components and move towards more complex and therapy-oriented gene circuits. A comprehensive list of ON-OFF switches, categorized into transcriptional, post-transcriptional, translational and post-translational, is presented in the first sections. Subsequently, Boolean logic gates, synthetic mammalian oscillators and toggle switches will be described. Several synthetic gene networks are further reviewed in the medical applications section, including cancer therapy gene circuits, immuno-regulatory networks, among others. The final sections focus on the applicability of synthetic gene networks to drug discovery, drug delivery, receptor-activating gene circuits and mammalian biomanufacturing processes. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  12. Mammalian Sperm Motility: Observation and Theory

    KAUST Repository

    Gaffney, E.A.; Gadê lha, H.; Smith, D.J.; Blake, J.R.; Kirkman-Brown, J.C.

    2011-01-01

    the mechanics of these specialized cells, especially during their remarkable journey to the egg. The biological structure of the motile sperm appendage, the flagellum, is described and placed in the context of the mechanics underlying the migration of mammalian

  13. Enhancer Evolution across 20 Mammalian Species

    Science.gov (United States)

    Villar, Diego; Berthelot, Camille; Aldridge, Sarah; Rayner, Tim F.; Lukk, Margus; Pignatelli, Miguel; Park, Thomas J.; Deaville, Robert; Erichsen, Jonathan T.; Jasinska, Anna J.; Turner, James M.A.; Bertelsen, Mads F.; Murchison, Elizabeth P.; Flicek, Paul; Odom, Duncan T.

    2015-01-01

    Summary The mammalian radiation has corresponded with rapid changes in noncoding regions of the genome, but we lack a comprehensive understanding of regulatory evolution in mammals. Here, we track the evolution of promoters and enhancers active in liver across 20 mammalian species from six diverse orders by profiling genomic enrichment of H3K27 acetylation and H3K4 trimethylation. We report that rapid evolution of enhancers is a universal feature of mammalian genomes. Most of the recently evolved enhancers arise from ancestral DNA exaptation, rather than lineage-specific expansions of repeat elements. In contrast, almost all liver promoters are partially or fully conserved across these species. Our data further reveal that recently evolved enhancers can be associated with genes under positive selection, demonstrating the power of this approach for annotating regulatory adaptations in genomic sequences. These results provide important insight into the functional genetics underpinning mammalian regulatory evolution. PMID:25635462

  14. Adaptation of the cardiovascular system to postinfarction cardiosclerosis in rats with congenital adrenoreactivity of the myocardium.

    Science.gov (United States)

    Usacheva, M A; Popkova, E V; Smirnova, E A; Saltykova, V A; Belkina, L M

    2007-12-01

    Three months after myocardial infarction the severity of heart failure and size of postinfarction scars in August rats with inherently reduced adrenoreactivity of the myocardium were similar to those in Wistar rats. The mortality rate in August rats was 2.5-fold lower than in Wistar rats. During the postinfarction period, myocardial adrenoreactivity in August rats remained lower, while the efficiency of cardiac function was 62% higher than in Wistar rats. The incidence of epinephrine-induced arrhythmias in August rats was much lower than in Wistar rats.

  15. Method for radio imaging the myocardium of mammals using radio-labelled lipophil cations

    International Nuclear Information System (INIS)

    1984-01-01

    The invention relates to a method for the radio imaging of myocardia of mammals by concentrating a radiolabelled cation in myocardial tissue and by producing a radiograph using imaging techniques. According to the invention, it is found that a group of substances shows a preference to myocardial tissues upon intravenous injection in mammals. The characteristic of the invention is that radiolabelled quaternary ammonium, quaternary phosphorous or quaternary arsenic compounds with at least two aryl groups are intravenously injected. These substances provide a sufficiently high radioactivity giving an approved diagnostic image of the myocardium. (G.J.P.)

  16. Mammalian Genetics and Teratology Section

    International Nuclear Information System (INIS)

    Anon.

    1980-01-01

    The work of the Mammalian Genetics and Teratology Section includes research in mutagenesis, basic genetics, reproductive biology, and teratogenesis involving basic studies, method development, including exploration of the biological material, and testing. The basic studies make good use of the genetic material accumulated in mutagenesis experiments of various kinds, or of the findings of mutagenesis experiments themselves. In the latter category is the finding of a repair system in the fertilized egg. The genetics of repair competency or deficiency are now under study. A linear relationship between gene dosage and level of expression of an enzyme has been demonstrated. Opportunities for the study of gene action are provided by a number of X-autosome translocations which continue to be discovered in the course of mutagenesis experiments. In these rearrangements, X-chromosome inactivation extends to neighboring autosomal loci. Considerable progress has been made in developing the skeletal mutation system, which provides information on dominants that is highly useful for risk assessment. A sensitive-indicator test is now under development which will make the screening for skeletal mutations much faster and easier. Method development has also progressed on the in vivo somatic-mutation test now being widely used as an in vivo screen for mutagens. Another method developed here is the numerical sex-chromosome anomaly (NSA) test for nondisjunction. The NSA method is being used to explore the effects of female age on chromosome loss and nondisjunction. A model for estimating the misclassification error was experimentally established for the heritable translocation test. A rapid, easy, and sensitive in vivo screening test for teratogenesis was developed. An in vitro teratogenic prescreen being developed makes use of teratocarcinoma-derived cell lines

  17. Electrical Signs predictors of malignant ventricular arrhythmias

    International Nuclear Information System (INIS)

    Aleman Fernandez, Ailema Amelia; Dorantes Sanchez, Margarita

    2012-01-01

    Recurrence of malignant ventricular arrhythmia is frequent in cardioverter-defibrillators related patients. The risk stratification is difficult, there are numerous electrocardiographic predictors but his sensibility and specificity are not absolute. The limit between normal and pathological is not defined, besides the complexity of ventricular arrhythmias. We expose different electrocardiographic predictors that can help to better individual risk stratification

  18. Bidirectional ventricular tachycardia of unusual etiology

    Directory of Open Access Journals (Sweden)

    Praloy Chakraborty

    2015-11-01

    Full Text Available Bidirectional ventricular tachycardia (BDVT is a rare form of ventricular arrhythmia, characterized by changing QRS axis of 180 degrees. Digitalis toxicity is considered as commonest cause of BDVT; other causes include aconite toxicity, myocarditis, myocardial infarction, metastatic cardiac tumour and cardiac channelopathies. We describe a case of BDVT in a patient with Anderson-Tawil syndrome.

  19. Detection of premature ventricular contractions on a ventricular electrocardiogram for patients with left ventricular assist devices.

    Science.gov (United States)

    Park, Sung Min; Lee, Jin Hong; Choi, Seong Wook

    2014-12-01

    The ventricular electrocardiogram (v-ECG) was developed for long-term monitoring of heartbeats in patients with a left ventricular assist device (LVAD) and does not normally have the functionality necessary to detect additional heart irregularities that can progress to critical arrhythmias. Although the v-ECG has the benefits of physiological optimization and counterpulsation control, when abnormal heartbeats occur, the v-ECG does not show the distinct abnormal waveform that enables easy detection of an abnormal heartbeat among normal heartbeats on the conventional ECG. In this study, the v-ECGs of normal and abnormal heartbeats are compared with each other with respect to peak-to-peak voltage, area, and maximal slopes, and a new method to detect abnormal heartbeats is suggested. In a series of animal experiments with three porcine models (Yorkshire pigs weighing 30-40 kg), a v-ECG and conventional ECG were taken simultaneously during LVAD perfusion. Clinical experts found 104 abnormal heartbeats from the saved conventional ECG data and confirmed that the other 3159 heartbeats were normal. Almost all of the abnormal heartbeats were premature ventricular contractions (PVCs), and there was short-term tachycardia for 3 s. A personal computer was used to automatically detect abnormal heartbeats with the v-ECG according to the new method, and its results were compared with the clinicians' results. The new method found abnormal heartbeats with 90% accuracy, and less than 15% of the total PVCs were missed. Copyright © 2014 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

  20. Delayed-enhancement MRI of apical hypertrophic cardiomyopathy: assessment of the intramural distribution and comparison with clinical symptoms, ventricular arrhythmias, and cine MRI

    International Nuclear Information System (INIS)

    Amano, Yasuo; Fukushima, Yoshimitsu; Kumita, Shinichiro; Takayama, Morimasa; Kitamura, Mitsunobu

    2011-01-01

    Background: Hypertrophic cardiomyopathy (HCM) is reported to show patchy midwall myocardial hyper enhancement on delayed-enhancement magnetic resonance imaging (DE-MRI). The intramural distribution of myocardial hyper enhancement and its correlation with clinical symptoms, ventricular arrhythmias, and cardiac function have not been described for symptomatic apical HCM. Purpose: To evaluate the features and significance of myocardial hyper enhancement on DE-MRI in symptomatic apical HCM. Material and Methods: Thirteen patients with symptomatic apical HCM and their 65 apical segments were investigated. Myocardial hyper enhancement and regional and global functional parameters were determined with MRI. We investigated the intramural distribution and frequencies of this myocardial hyper enhancement and compared them with the patients' clinical symptoms, the presence of ventricular arrhythmias, and cine MRI. Results: Eight (61.5%) patients with symptomatic apical HCM displayed apical myocardial hyper enhancement, and 22 (33.8%) of the 65 apical segments examined showed myocardial hyper enhancement. Of the myocardial hyper enhancement observed, 81.8% showed a subendocardial pattern.The Hyperenhanced apical myocardium had a lower percentage of systolic myocardial thickening, and was associated with serious symptoms (e.g. syncope) and ventricular arrhythmias. Conclusion: Patients with symptomatic apical HCM showed myocardial hyper enhancement involving the subendocardial layer, which might be related to regional systolic dysfunction, serious clinical symptoms, and ventricular arrhythmias

  1. Evaluation of changes in left ventricular structure and function in hypertensive patients with coronary artery disease after PCI using real-time three-dimensional echocardiography.

    Science.gov (United States)

    Meng, Yanhong; Zong, Ling; Zhang, Ziteng; Han, Youdong; Wang, Yanhui

    2018-02-01

    We aimed to evaluate the changes in left ventricular structure and function in hypertensive patients with coronary artery disease before and after percutaneous coronary intervention (PCI) using real-time three-dimensional echocardiography. Two hundred and eighty hypertensive patients with coronary artery disease undergoing PCI and 120 cases who did not receive PCI in our hospital were selected as the subjects of our study. All patients were administered with routine antiplatelet, anticoagulant, lipid-lowering, antihypertensive, dilating coronary artery and other medications. The left ventricular systolic function and systolic synchrony index changes before and after subjects were treated by PCI were analyzed using three-dimensional echocardiography. At 2 days before surgery, there were no significant differences in the left ventricular end-diastolic volume, left ventricular end-systolic volume (LVESV) and ejection fraction (EF) between the two patient groups (P>0.05). At 3 months and 9 months, the two key time points after PCI, the LVESV level in the PCI group was distinctly decreased, while EF was significantly increased (P0.05); however, the parameters of time from the corresponding segment of the myocardium to the minimal systolic volume in patients in the PCI group were significantly reduced at 3 and 9 months after surgery (PPCI accurately and in real-time, which may play a significant role.

  2. Predictors of the left ventricular dysfunction induced by ventricular arrhythmia

    Directory of Open Access Journals (Sweden)

    А. І. Vytryhovskiy

    2016-08-01

    Full Text Available The most powerful predictor of life-threatening arrhythmia risk is a combination of low heart rate variability with low ejection fraction (EF of the left ventricle. Aim. To identify predictors of left ventricle dysfunction which is induced by ventricular arrhythmia. Materials and methods. To diagnose structural changes of left ventricular functional capacity and reserves in patients with previous myocardial infarction and patients with high and very high cardiovascular risk by SCORE scale and for establishment the relationship between morphological heart changes and pathological phenomenon of heart turbulence echocardiography and study of heart rate turbulence variability were performed. 603 patients were selected for the research. All patients were divided into groups: group 1 – patients with coronary heart disease, but without associated risk factors, such as smoking, obesity, metabolic syndrome; group 2 – patients who smoke tobacco more than 2 years (very high cardiovascular risk by scale SCORE; group 3 – patients with metabolic syndrome without coronary heart disease or arterial hypertension (very high cardiovascular risk by scale SCORE. The control group consisted of 149 persons. Results. The feature of structural changes in patients with myocardial infarction and in patients with a high cardiovascular risk by SCORE with heart rate turbulence compared with cases without НRT is considerably thickening of the left interventricular septum in systole. Based on this, it can be argued that the emergence of ventricular arrhythmia and accordingly phenomenon of heart rate turbulence in patients with existing cardiovascular diseases and risk factors has both morphological and functional character. Significant difference of echocardioscopy parameters in patients with postinfarction cardiosclerosis and risk factors by the SCORE system was established by index of intraventricular septum thickness in systole, and in persons with high risk – in

  3. Paeoniflorin improves cardiac function and decreases adverse postinfarction left ventricular remodeling in a rat model of acute myocardial infarction

    Directory of Open Access Journals (Sweden)

    Chen H

    2018-04-01

    Full Text Available Hengwen Chen,* Yan Dong,* Xuanhui He, Jun Li, Jie Wang Guang’anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, China *These authors contributed equally to this work Background: Paeoniflorin (PF is the active component of Paeonia lactiflora Pall. or Paeonia veitchii Lynch. This study was, therefore, aimed to evaluate the improvement and mechanism of the PF on ventricular remodeling in rats with acute myocardial infarction (AMI. Materials and methods: In this study, AMI model was established by ligating the anterior descending coronary artery in Wistar rats. After 4 weeks gavage of PF, the apparent signs and the left ventricle weight index of Wistar rats were observed. The left ventricular ejection fraction (LVEF was evaluated by Doppler ultrasonography. Changes in cardiac morphology were observed by pathologic examination, and apoptosis was observed by the terminal deoxynucleotidyl transferase dUTP nick end labeling assay. In addition, enzyme-linked immunosorbent assay was used to detect the expression of tumor necrosis factor-α (TNF-α, interleukin-6 (IL-6 interleukin-10 (IL-10 and brain natriuretic peptide (BNP. Immunohistochemistry and Western blot method were applied to detect Caspase-3 and Caspase-9. Results: Compared with the model control, the survival conditions of rats in all treatment groups were generally improved after PF treatment. LVEF was significantly increased, and both left ventricular end-diastolic inner diameter and left ventricular end-systolic inner diameter were significantly reduced. Moreover, pathologic examination showed that the myocardium degeneration of the rats treated with PF was decreased, including neater arrangement, more complete myofilament, more uniform gap and less interstitial collagen fibers. Furthermore, the mitochondrial structure of cardiomyocytes was significantly improved. The ultrastructure was clear, and the arrangement of myofilament was more regular. Also, the expression of

  4. DYNAMICS OF STRUCTURAL AND FUNCTIONAL STATUS OF MYOCARDIUM DUE TO COMBINATION THERAPY WITH AMLODIPINE AND BISOPROLOL IN PATIENTS WITH ARTERIAL HYPERTENSION

    Directory of Open Access Journals (Sweden)

    I. L. Zapesochnaya

    2015-09-01

    Full Text Available Aim. To evaluate the effect of 6-month therapy with combination of amlodipine and bisoprolol on the structural and functional status of the myocardium in hypertensive patients who work in the Far North.Material and methods. 140 hypertensive patients who live in the Khanty-Mansiysk Autonomous District - Yugra were divided into two groups depending on arrangement of working time. The first group included 72 patients who work only day shift; the second group – 68 patients who work alternate (day/night shifts. Combination therapy with amlodipine and bisoprolol assigned to all patients. Echocardiography was performed at baseline, after 12 weeks, and after 6 months of therapy.Results. The target blood pressure (BP level in group 1 was achieved in 92.9%. A share of patients with normal left ventricular (LV geometry increased from 37.5 to 44.8%; a share of patients with concentric and eccentric LV hypertrophy (LVH decreased from 30.6 to 23.9% and 19.4 to 19.2%, respectively. Target BP level in group 2 was achieved in 87.9%. A share of patients with normal LV geometry increased from 23.5 to 33.3%; while share of patients with concentric and eccentric LVH decreased from 45.6 to 38.1% and from 19.1 to 17.4%, respectively. A positive correlation between LV myocardial index and average daily systolic and diastolic BP was found.Conclusion. Revealed changes in BP and in LV structure and function due to treatment with amlodipine and bisoprolol can be considered as cardioprotective effect of this combination in hypertensive patients who work in the Far North. This effect was more pronounced in hypertensive patients working alternate (day/night shifts.

  5. The evaluation of viability in infarcted myocardium using gated blood pool scintigraphy during combined infusion of isosorbide dinitrate and dobutamine infusion

    Energy Technology Data Exchange (ETDEWEB)

    Kubota, Yasushi; Sugihara, Hiroki; Nakagawa, Tatsuya (Kyoto Prefectural Univ. of Medicine (Japan)) (and others)

    1990-02-01

    Nineteen patients with acute or old myocardial infarction underwent ECG-gated blood pool scintigraphy after iv injection of isosorbide dinitrate (ISDN) and combined ISDN and dobutamine (D) (ISDN+D), with the purpose of evaluating wall motion abnormality, as well as hemodynamic parameters. Heart rate increased after iv injection of both ISDN and ISDN+D. Although diastolic and systolic blood pressures decreased with ISDN, they increased with ISDN+D. Left ventricular ejection fraction (EF) increased by iv injection of ISDN+D. Both end-diastolic and end-systolic volumes decreased with ISDN and ISDN+D. A decreased stroke volume was also associated with iv injection of ISDN. Wall motion abnormality in the infarcted myocardium was graded on a 1-5 score: 1-dyskinesis, 2-akinesis, 3-severe hypokinesis, 4-mild hypokinesis, and 5-normal. Improvement was observed in 43% for dyskinesis after iv injection of both ISDN and ISDN+D; in 54% and 65%, with ISDN and ISDN+D respectively, for akinesis and 53% and 77% for severe hypokinesis. In comparing wall motion score with relative Tl uptake (RTU) on exercise Tl-201 scintigraphy, the correlation between wall motion score and RTU on the 3-hr image was higher after iv injection of ISDN+D (r=0.66) than after iv injection of ISDN (r=0.57). Although a significantly improved regional EF after iv injection of ISDN+D was associated with redistributed segments on the 3-hr image, regional EF was sometimes improved even in the non-redistributed segments on the 3-hr image. (N.K.).

  6. DYNAMICS OF STRUCTURAL AND FUNCTIONAL STATUS OF MYOCARDIUM DUE TO COMBINATION THERAPY WITH AMLODIPINE AND BISOPROLOL IN PATIENTS WITH ARTERIAL HYPERTENSION

    Directory of Open Access Journals (Sweden)

    I. L. Zapesochnaya

    2014-01-01

    Full Text Available Aim. To evaluate the effect of 6-month therapy with combination of amlodipine and bisoprolol on the structural and functional status of the myocardium in hypertensive patients who work in the Far North.Material and methods. 140 hypertensive patients who live in the Khanty-Mansiysk Autonomous District - Yugra were divided into two groups depending on arrangement of working time. The first group included 72 patients who work only day shift; the second group – 68 patients who work alternate (day/night shifts. Combination therapy with amlodipine and bisoprolol assigned to all patients. Echocardiography was performed at baseline, after 12 weeks, and after 6 months of therapy.Results. The target blood pressure (BP level in group 1 was achieved in 92.9%. A share of patients with normal left ventricular (LV geometry increased from 37.5 to 44.8%; a share of patients with concentric and eccentric LV hypertrophy (LVH decreased from 30.6 to 23.9% and 19.4 to 19.2%, respectively. Target BP level in group 2 was achieved in 87.9%. A share of patients with normal LV geometry increased from 23.5 to 33.3%; while share of patients with concentric and eccentric LVH decreased from 45.6 to 38.1% and from 19.1 to 17.4%, respectively. A positive correlation between LV myocardial index and average daily systolic and diastolic BP was found.Conclusion. Revealed changes in BP and in LV structure and function due to treatment with amlodipine and bisoprolol can be considered as cardioprotective effect of this combination in hypertensive patients who work in the Far North. This effect was more pronounced in hypertensive patients working alternate (day/night shifts.

  7. Metabolic borderzone in acutely ischemic canine myocardium demonstrated by positron-CT (PCT)

    International Nuclear Information System (INIS)

    Schwaiger, M.; Hansen, H.; Selin, C.; Wittmer, S.; Barrio, J.; Schelbert, H.R.

    1984-01-01

    Acute coronary ligation in dogs results in an area of myocardial dysfunction that exceeds the area of subsequent necrosis suggesting the existence of an ischemic ''borderzone'' of reversibly injured myocardium. The authors tested this hypothesis in 9 closed chest dogs with C-11 plamitate (CPA) and serial PCT imaging after an LAD occlusion. Using a blood flow (MBF) image obtained with iv N-13 ammonia prior to CPA, regions of interest were assigned on the serial CPA cross-sectional images to the center (IC) and border (IB) of the ischemic segment and to control myocardium (CO). CPA uptake was closely related to MBF (r=0.88) implicating flow as a major determinant of CPA uptake. Clearance helftimes (T 1/2) and relative sizes (RS) of the early rapid phase on the C-11 tissue time activity curves were determined for IC, IB and CO. In IC, MBF, RS and T 1/2 were markedly depressed indicating impaired CPA utilization and oxidation. In IB, MBF was less than in CO though only insignificantly, while RS and T 1/2 were highly abnormal. The authors conclude that FFA metabolism in areas adjacent to ischemic segments but without significant MBF decreases in abnormal, presenting evidence for a metabolic borderzone which now can be identified noninvasively with positron emission tomography

  8. Study of shape memory alloy fibers for the development of artificial myocardium.

    Science.gov (United States)

    Hassoulas, Ioannis A; Ladopoulos, Vlassios S; Kalogerakos, Paris-Dimitrios K

    2010-01-01

    Circulatory support devices are employed to treat heart failure. Such a device could be made from shape memory alloy (SMA) fibers. These Ni-Ti fibers contract when electric current flows through them, thus resembling artificial muscles. An artificial myocardium device made from SMA fibers can directly compress the epicardial surface of a failing heart, thus contributing to the pumping action. Unlike modern mechanical circulatory support devices, there is no blood-contacting surface to provoke thromboembolism, hemorrhage, inflammatory response or hemolysis. The experimental setup permitted a detailed study of a sample SMA fiber with great accuracy while the ambient temperature was controlled to resemble that of the human body. The current profile through the fiber was controlled (current shaping, CS) by a microcontroller and a portable computer. Parameters such as strain, contraction and relaxation velocities and the effect of ambient temperature were measured. The contraction and relaxation velocities were measured after applying various effective currents. It was found that the contraction velocity could be manipulated to reach that of the healthy myocardium through CS. On the other hand, the relaxation velocity was independent of the contraction velocity. A cardiac assist device can be made from SMA fibers. More studies need to be conducted in this direction.

  9. Study on the kinetics of high-energy phosphates in myocardium by phosphorous nuclear magnetic resonance

    Energy Technology Data Exchange (ETDEWEB)

    Kusuoka, Hideo; Tsuneoka, Yutaka; Inoue, Michitoshi; Abe, Hiroshi [Osaka Univ. (Japan). Faculty of Medicine; Watari, Hiroshi

    1982-12-01

    Effect of artificial blood, FC 43 (Perfluorochemicals) on the kinetics of high-energy phosphate in the myocardium was evaluated by /sup 31/P-NMR which permits a continuous and non-invasive assessment of in vivo phosphorus compounds. Cardiac perfusion was carried out on a excised rat heart with a Krebs-Henseleit modified solution and FC 43 alternately. Under the normal condition, ischemic condition, and at second perfusion amounts of intramyocardial creatine phosphoric acid, ATP, and inorganic phosphorus were determined by /sup 31/P-NMR. Coronary flow was simultaneously estimated. The ischemic state due to interruption of perfusion resulted in a decrease in creatine phosphoric acid, which was associated with an increase in inorganic phosphorus and intracellular acidosis. No change of ATP amount was observed under ischemic state. With resumption of perfusion, the levels of creatine phosphoric acid and inorganic phosphorus rapidly returned to the normal. In the group of FC 43, coronary flow was 2.68 ml/min/g of the heart weight, about 1/2 of that of the Krebs-Henseleit group (5.68 ml/min/g of the heart weight). In controls, there was no difference between the two groups concerning creatine phosphoric acid level and recovery of creatine phospohric acid level after ischemia. These results showed that FC 43 supplies sufficient oxygen, and has no effect on the kinetics of energy in the myocardium.

  10. Segmenting high-frequency intracardiac ultrasound images of myocardium into infarcted, ischemic, and normal regions.

    Science.gov (United States)

    Hao, X; Bruce, C J; Pislaru, C; Greenleaf, J F

    2001-12-01

    Segmenting abnormal from normal myocardium using high-frequency intracardiac echocardiography (ICE) images presents new challenges for image processing. Gray-level intensity and texture features of ICE images of myocardium with the same structural/perfusion properties differ. This significant limitation conflicts with the fundamental assumption on which existing segmentation techniques are based. This paper describes a new seeded region growing method to overcome the limitations of the existing segmentation techniques. Three criteria are used for region growing control: 1) Each pixel is merged into the globally closest region in the multifeature space. 2) "Geographic similarity" is introduced to overcome the problem that myocardial tissue, despite having the same property (i.e., perfusion status), may be segmented into several different regions using existing segmentation methods. 3) "Equal opportunity competence" criterion is employed making results independent of processing order. This novel segmentation method is applied to in vivo intracardiac ultrasound images using pathology as the reference method for the ground truth. The corresponding results demonstrate that this method is reliable and effective.

  11. Biophysical foundations for the study of the electrical excitability and action potential propagation in myocardium

    International Nuclear Information System (INIS)

    Suarez Antola, R.

    1991-01-01

    The electric current flow in the heterogeneous and anysotropic volume conductor of the myocardium is studied. The equations of bidomain theory are derived using an approach framed in the theory of averaged fields, introducing microscopic, mesoscopic and macroscopic spatial scales. However, the procedure, compatible with the histological and the anatomical details of the organ, is different from the multiple scale asymptotic expansions usually applied in homogeneization problems. A probabilistic approach framed in large numbers theorems is used to derive the equation for membrane ionic current from the stochastic activity of the channels at the microscopic level. An operational procedure suitable to define a sharp bidomain boundary from the fuzzy distribution of structural details and physical properties at the histological level is given. The problem of threshold is studied. The sizes and shapes of critical masses of cardiac cells that must be depolarized above threshold in order to produce a propagated action potential are determined by an approximate analytical procedure. The concept of family of threshold patterns for the emergence of action potentials in the heart is introduced. This concept is applied to discuss the conditions of emergence of ectopic focus. Analytical formulae are derived, for the time constant and the rheobase for electrical stimulation of the myocardium. These formulae are in good agreement with known experimental results. New experiments that could be done to confirm or reject them are suggested

  12. Intrinsic washout rates of thallium-201 in normal and ischemic myocardium after dipyridamole-induced vasodilation

    International Nuclear Information System (INIS)

    Beller, G.A.; Holzgrefe, H.H.; Watson, D.D.

    1985-01-01

    Infusion of dipyridamole has been suggested as an alternative to exercise stress for myocardial perfusion imaging for detection of ischemia, but the mechanism and significance of thallium-201 ( 201 Tl) redistribution after administration of dipyridamole are uncertain. If disparate intrinsic cellular efflux rates of 201 Tl from normal and relatively underperfused myocardium in response to dipyridamole-induced vasodilation were observed, this could explain delayed 201 Tl redistribution. We investigated the effect of an intravenous infusion of 0.15 mg/kg dipyridamole on the intrinsic myocardial washout rate of 201 Tl as measured with a gamma-detector probe after intracoronary injection (50 muCi) of the radionuclide in open-chested anesthetized dogs. In six normal dogs the t 1/2 for intrinsic 201 Tl washout from the myocardium was 89 +/- 11 min (SE) at control conditions and became more rapid at 59 +/- 10 min (p . .0001) after dipyridamole. This corresponded to a significant increase in microsphere-determined epicardial (0.95 +/- 0.11 to 2.23 +/- 0.46 ml/min/g; p . .01) and endocardial (0.86 +/- 0.10 to 1.53 +/- 0.27; p . .029) flows. In 12 dogs with a critical coronary stenosis, the 201 Tl intrinsic washout rate slowed from 70 +/- 5 to 104 +/- 6 min (p . .0001) after production of the stenosis and slowed even further to 169 +/- 21 min (p . .003) after dipyridamole

  13. Oxygen supply and oxidative phosphorylation limitation in rat myocardium in situ.

    Science.gov (United States)

    Kreutzer, U; Mekhamer, Y; Chung, Y; Jue, T

    2001-05-01

    The 1H-NMR signal of the proximal histidyl-N(delta)H of deoxymyoglobin is detectable in the in situ rat myocardium and can reflect the intracellular PO2. Under basal normoxic conditions, the cellular PO2 is sufficient to saturate myoglobin (Mb). No proximal histidyl signal of Mb is detectable. On ligation of the left anterior descending coronary artery, the Mb signal at 78 parts/million (ppm) appears, along with a peak shoulder assigned to the corresponding signal of Hb. During dopamine infusion up to 80 microg. kg(-1) x min(-1), both the heart rate-pressure product (RPP) and myocardial oxygen consumption (MVO2) increase by about a factor of 2. Coronary flow increases by 84%, and O2 extraction (arteriovenous O2 difference) rises by 31%. Despite the increased respiration and work, no deoxymyoglobin signal is detected, implying that the intracellular O2 level still saturates MbO2, well above the PO2 at 50% saturation of Mb. The phosphocreatine (PCr) level decreases, however, during dopamine stimulation, and the ratio of the change in P(i) over PCr (DeltaP(i)/PCr) increases by 0.19. Infusion of either pyruvate, as the primary substrate, or dichloroacetate, a pyruvate dehydrogenase activator, abolishes the change in DeltaP(i)/PCr. Intracellular O2 supply does not limit MVO2, and the role of ADP in regulating respiration in rat myocardium in vivo remains an open question.

  14. Biomechanical and Hemodynamic Measures of Right Ventricular Diastolic Function: Translating Tissue Biomechanics to Clinical Relevance.

    Science.gov (United States)

    Jang, Sae; Vanderpool, Rebecca R; Avazmohammadi, Reza; Lapshin, Eugene; Bachman, Timothy N; Sacks, Michael; Simon, Marc A

    2017-09-12

    Right ventricular (RV) diastolic function has been associated with outcomes for patients with pulmonary hypertension; however, the relationship between biomechanics and hemodynamics in the right ventricle has not been studied. Rat models of RV pressure overload were obtained via pulmonary artery banding (PAB; control, n=7; PAB, n=5). At 3 weeks after banding, RV hemodynamics were measured using a conductance catheter. Biaxial mechanical properties of the RV free wall myocardium were obtained to extrapolate longitudinal and circumferential elastic modulus in low and high strain regions (E 1 and E 2 , respectively). Hemodynamic analysis revealed significantly increased end-diastolic elastance (E ed ) in PAB (control: 55.1 mm Hg/mL [interquartile range: 44.7-85.4 mm Hg/mL]; PAB: 146.6 mm Hg/mL [interquartile range: 105.8-155.0 mm Hg/mL]; P =0.010). Longitudinal E 1 was increased in PAB (control: 7.2 kPa [interquartile range: 6.7-18.1 kPa]; PAB: 34.2 kPa [interquartile range: 18.1-44.6 kPa]; P =0.018), whereas there were no significant changes in longitudinal E 2 or circumferential E 1 and E 2 . Last, wall stress was calculated from hemodynamic data by modeling the right ventricle as a sphere: stress=Pressure×radius2×thickness. RV pressure overload in PAB rats resulted in an increase in diastolic myocardial stiffness reflected both hemodynamically, by an increase in E ed , and biomechanically, by an increase in longitudinal E 1 . Modest increases in tissue biomechanical stiffness are associated with large increases in E ed . Hemodynamic measurements of RV diastolic function can be used to predict biomechanical changes in the myocardium. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

  15. Left Ventricular Geometry and Blood Pressure as Predictors of Adverse Progression of Fabry Cardiomyopathy.

    Directory of Open Access Journals (Sweden)

    Johannes Krämer

    Full Text Available In spite of several research studies help to describe the heart in Fabry disease (FD, the cardiomyopathy is not entirely understood. In addition, the impact of blood pressure and alterations in geometry have not been systematically evaluated.In 74 FD patients (mean age 36±12 years; 45 females the extent of myocardial fibrosis and its progression were quantified using cardiac magnetic-resonance-imaging with late enhancement technique (LE. Results were compared to standard echocardiography complemented by 2D-speckle-tracking, 3D-sphericity-index (SI and standardized blood pressure measurement. At baseline, no patient received enzyme replacement therapy (ERT. After 51±24 months, a follow-up examination was performed.Systolic blood pressure (SBP was higher in patients with vs. without LE: 123±17 mmHg vs. 115±13 mmHg; P = 0.04. A positive correlation was found between SI and the amount of LE-positive myocardium (r = 0.51; P<0.001 indicating an association of higher SI in more advanced stages of the cardiomyopathy. SI at baseline was positively associated with the increase of LE-positive myocardium during follow-up. The highest SBP (125±19 mmHg and also the highest SI (0.32±0.05 was found in the subgroup with a rapidly increasing LE (ie, ≥0.2% per year; n = 16; P = 0.04. Multivariate logistic regression analysis including SI, SBP, EF, left ventricular volumes, wall thickness and NT-proBNP adjusted for age and sex showed SI as the most powerful parameter to detect rapid progression of LE (AUC = 0.785; P<0.05.LV geometry as assessed by the sphericity index is altered in relation to the stage of the Fabry cardiomyopathy. Although patients with FD are not hypertensive, the SBP has a clear impact on the progression of the cardiomyopathy.

  16. Absence of cystatin C involvement in ventricular remodelling and heart failure.

    Science.gov (United States)

    Pérez-Calvo, J I; Castiella Muruzábal, T; Búcar Barjud, M; Josa Laorden, C; Sánchez Marteles, M; Lacambra Blasco, I; Asensio López, M C; Pascual Figal, D A

    2016-03-01

    Cystatin C (CysC) is a protease encoded by housekeeping genes. Although its prognostic value in heart failure (HF) is well known, it is debatable whether this value is due to the greater accuracy of CysC in calculating the glomerular filtration rate or to its involvement in pathological ventricular remodelling. The aim of this study was to determine whether CysC expression changes in the myocardium of foetuses of different ages and in the myocardium of adults with various cardiovascular diseases, as well as to analyse the correlation between its serum concentrations and cardiac structure and morphology in a patient group with HF. We analysed the correlations (Pearson's r and Spearman's test) between the serum CysC levels and echocardiographic parameters of 351 patients with HF. We also performed immunohistochemical staining for CysC, metalloproteinase-9 (MMP-9) and desmin in 9 cardiac tissue samples from autopsies of 4 foetuses of different gestational ages and 5 healthy adults or adults with cardiovascular disease. For the patients with HF, there was no correlation between the CysC concentrations and the cardiac parameters measured by 2D echocardiography. The immunohistochemistry showed a weak background staining for CysC in all samples, regardless of age and the presence or absence of cardiovascular diseases. Our results suggest that CysC does not have a significant role in the pathological remodelling of the left ventricle in HF. Copyright © 2015 Elsevier España, S.L.U. y Sociedad Española de Medicina Interna (SEMI). All rights reserved.

  17. Focalized contractile impairment at hypertrophied myocardium proven in consideration of wall stress in patients with hypertrophic cardiomyopathy

    International Nuclear Information System (INIS)

    Yamazaki, Tadashi; Suzuki, Jun-ichi; Shimamoto, Ryoichi; Tsuji, Taeko; Ohmoto, Yuki; Toyo-oka, Teruhiko; Omata, Masao; Ohtomo, Kuni; Nagai, Ryozo

    2006-01-01

    In hypertrophic cardiomyopathy (HCM) a hyperkinetic state is sometimes observed in spite of impaired systolic function in the hypertrophied myocardium. The aim of the present study was to determine the mechanism of this paradox. Seventeen patients with HCM and 10 normal subjects underwent cine magnetic resonance (MR) imaging to measure percent systolic wall thickening and percent fractional shortening. The ratio of systolic radial wall stress of the LV at the hypertrophied myocardium over that at the nonhypertrophied myocardium was evaluated to describe the focal advantageous condition for wall thickening. The ratio was 0.66±0.36 at the start of contraction and 0.78±0.31 at early-systole, indicating consistently smaller radial wall stress at the hypertrophied myocardium. Although the condition for contraction was favorable (a ratio less than 1.00), percent systolic wall thickening at the hypertrophied myocardium (23.0±11.8%) was smaller than that at the nonhypertrophied myocardium (70.5±32.3%). Smaller end-diastolic dimension (HCM group; 45.2±4.2 mm, reference group; 48.9±4.1 mm, P=0.04) with a statistically identical value of systolic decrease in intraventricular dimension (HCM group; 19.7±3.9 mm, reference group; 18.9±3.2 mm, P=0.60) yielded high percent fractional shortening in patients with HCM (43.5±7.6%). Although contractile impairment was proven at the hypertrophied region with low radial wall stress in the HCM group, the smaller end-diastolic dimension in this group resulted in high percent fractional shortening. (author)

  18. Evaluation of left ventricular volumes in patients with congenital heart disease and abnormal left ventricular geometry. Comparison of MRI and transthoracic 3-dimensional echocardiography

    International Nuclear Information System (INIS)

    Gutberlet, M.; Grothoff, M.; Roettgen, R.; Lange, P.; Felix, R.; Abdul-Khaliq, H.; Schroeter, J.; Schmitt, B.; Vogel, M.

    2003-01-01

    Purpose: To assess the new method of 3-dimensional echocardiography in comparison to the 'gold standard' MRI as to its ability to calculate left ventricular volumes in patients with congenital heart disease. Materials and methods: Eighteen patients between the ages of 3.9 to 37.3 years (mean: 12.8±9.7) with a geometrically abnormal left ventricle were examined using a 1.5 T scanner with a fast gradient-echo sequence (TR=14 ms, TE=2.6-2.9 ms, FOV=300-400 mm, flip angle=20 , matrix=128:256, slice thickness=5 mm, retrospective gating) in multislice-multiphase technique. Transthoracic 3D-echocardiography was performed with a 3.5 MHz transducer and a Tomtec trademark (Munich, Germany) system for 3D reconstruction. Results: Volume calculation was possible in all patients with 3D-echocardiography, but the muscle mass calculation only succeeded in 11 to 18 patients (61%) due to inadequate visualization of the entire myocardium. Comparing MRI and 3D-echocardiography, the correlation was r=0.97 for the end-systolic volumes, r=0.98 for the end-diastolic volumes, r=0.79 for the end-systolic muscle mass and r=0.77 for the end-diastolic muscle mass. The agreement between both methods was considered good for the calculated end-diastolic volumes and sufficient for the calculated end-systolic volumes. The muscle mass calculations showed larger differences especially for the end-systolic mass. Mean intraobserver variability was 18.6% for end-systolic and 8.3% for end-diastolic volumes. Conclusion: In patients with an abnormal left ventricular configuration due to congenital heart disease, the new method of 3D-echocardiography is sufficient for volume calculations in preselected patients. The high intraobserver variability is still a limitation of transthoracic 3D-echocardiography in comparison to MRI. (orig.) [de

  19. Manifestation of automaticity in the pulmonary-vein myocardium of rats with abdominal aorto-venocaval shunt

    Directory of Open Access Journals (Sweden)

    Shogo Hamaguchi

    2015-08-01

    Full Text Available Effect of abdominal aorto-venocaval shunt (AVS on the automaticity of the pulmonary-vein myocardium was studied in the rat. Spontaneous electrical activity was observed in one third of the isolated pulmonary-vein preparations from the AVS rats, but scarcely in those from sham-operated rats; the activity was induced by tertiapin and suppressed by carbachol or chelation of intracellular Ca2+. The evoked action potentials in AVS rats had less negative resting membrane potential and longer action potential duration than those in sham-operated rats. These results suggest that the automaticity of the rat pulmonary-vein myocardium is manifested under chronic volume overload.

  20. Arteriosclerotic changes in the myocardium, lung, and kidney in dogs with chronic congestive heart failure and myxomatous mitral valve disease

    DEFF Research Database (Denmark)

    Falk, Bo Torkel; Jönsson, Lennart; Olsen, Lisbeth Høier

    2006-01-01

    Background: The occurrence of small vessel arteriosclerosis in the myocardium, kidney, and lung in dogs with naturally occurring myxomatous mitral valve disease has not been previously investigated systematically. Methods: Twenty-one dogs with naturally occurring congestive heart failure and 21 age......-matched, sex-matched, and weight-matched control dogs underwent extensive pathological and histopathological examination. Morphometry and scoring of tissue sections were used to measure arterial narrowing and fibrosis in the myocardium, kidney, and lung; and intimal thickness and plaque formation in the aorta...... and pulmonary artery. Results: Dogs with congestive heart failure had significantly more arterial narrowing in the left ventricle (Pdogs. However...

  1. Inhibitory Effect of Vascular Endothelial Growth Factor on the Slowly Activating Delayed Rectifier Potassium Current in Guinea Pig Ventricular Myocytes.

    Science.gov (United States)

    Lin, Zhenhao; Xing, Wenlu; Gao, Chuanyu; Wang, Xianpei; Qi, Datun; Dai, Guoyou; Zhao, Wen; Yan, Ganxin

    2018-01-26

    Vascular endothelial growth factor (VEGF) exerts a number of beneficial effects on ischemic myocardium via its angiogenic properties. However, little is known about whether VEGF has a direct effect on the electrical properties of cardiomyocytes. In the present study, we investigated the effects of different concentrations of VEGF on delayed rectifier potassium currents (I K ) in guinea pig ventricular myocytes and their effects on action potential (AP) parameters. I K and AP were recorded by the whole-cell patch clamp method in ventricular myocytes. Cells were superfused with control solution or solution containing VEGF at different concentrations for 10 minutes before recording. Some ventricular myocytes were pretreated with a phosphatidylinositol 3-kinase inhibitor for 1 hour before the addition of VEGF. We found that VEGF inhibited the slowly activating delayed rectifier potassium current (I K s ) in a concentration-dependent manner (18.13±1.04 versus 12.73±0.34, n=5, P =0.001; 12.73±0.34 versus 9.05±1.20, n=5, P =0.036) and prolonged AP duration (894.5±36.92 versus 746.3±33.71, n=5, P =0.021). Wortmannin, a phosphatidylinositol 3-kinase inhibitor, eliminated these VEGF-induced effects. VEGF had no significant effect on the rapidly activating delayed rectifier potassium current (I K r ), resting membrane potential, AP amplitude, or maximal velocity of depolarization. VEGF inhibited I K s in a concentration-dependent manner through a phosphatidylinositol 3-kinase-mediated signaling pathway, leading to AP prolongation. The results indicate a promising therapeutic potential of VEGF in prevention of ventricular tachyarrhythmias under conditions of high sympathetic activity and ischemia. © 2018 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

  2. β1-Adrenoceptor blocker aggravated ventricular arrhythmia.

    Science.gov (United States)

    Wang, Yan; Patel, Dimpi; Wang, Dao Wu; Yan, Jiang Tao; Hsia, Henry H; Liu, Hao; Zhao, Chun Xia; Zuo, Hou Juan; Wang, Dao Wen

    2013-11-01

    To assess the impact of β1 -adrenoceptor blockers (β1 -blocker) and isoprenaline on the incidence of idiopathic repetitive ventricular arrhythmia that apparently decreases with preprocedural anxiety. From January 2010 to July 2012, six patients were identified who had idiopathic ventricular arrhythmias that apparently decreased (by greater than 90%) with preprocedural anxiety. The number of ectopic ventricular beats per hour (VPH) was calculated from Holter or telemetry monitoring to assess the ectopic burden. The mean VPH of 24 hours from Holter before admission (VPH-m) was used as baseline (100%) for normalization. β1 -Blockers, isoprenaline, and/or aminophylline were administrated successively on the ward and catheter lab to evaluate their effects on the ventricular arrhythmias. Among 97 consecutive patients with idiopathic ventricular arrhythmias, six had reduction in normalized VPHs in the hour before the scheduled procedure time from (104.6 ± 4.6%) to (2.8 ± 1.6%) possibly due to preprocedural anxiety (P < 0.05), then increased to (97.9 ± 9.7%) during β1 -blocker administration (P < 0.05), then quickly reduced to (1.6 ± 1.0%) during subsequent isoprenaline infusion. Repeated β1 -blocker quickly counteracted the inhibitory effect of isoprenaline, and VPHs increased to (120.9 ± 2.4%) from (1.6 ± 1.0%; P < 0.05). Isoprenaline and β1 -blocker showed similar effects on the arrhythmias in catheter lab. In some patients with structurally normal heart and ventricular arrhythmias there is a marked reduction of arrhythmias associated with preprocedural anxiety. These patients exhibit a reproducible sequence of β1 -blocker aggravation and catecholamine inhibition of ventricular arrhythmias, including both repetitive ventricular premature beats and monomorphic ventricular tachycardia. ©2013, The Authors. Journal compilation ©2013 Wiley Periodicals, Inc.

  3. Remodelado ventricular y cirugía

    Directory of Open Access Journals (Sweden)

    Ignacio Moriones

    2008-01-01

    Se han diseñado anillos mitrales como el de Carpentier- McCarthy-Adams (IMR ETlogix™ para pacientes isquémicos, o el Edwards-Geoform™ en miocardiopatías. La asistencia ventricular puede conseguir en determinados casos recuperación permanente del volumen de la cavidad y función ventricular, particularmente en miocarditis y determinadas miocardiopatías. Paralelamente, se han iniciado experiencias con el sistema de contención CorCap o el sistema Myosplint. Finalmente, la actuación sobre las valvulopatías y la revascularización favorecen la restauración ventricular.

  4. Mosaic evolution of the mammalian auditory periphery.

    Science.gov (United States)

    Manley, Geoffrey A

    2013-01-01

    The classical mammalian auditory periphery, i.e., the type of middle ear and coiled cochlea seen in modern therian mammals, did not arise as one unit and did not arise in all mammals. It is also not the only kind of auditory periphery seen in modern mammals. This short review discusses the fact that the constituents of modern mammalian auditory peripheries arose at different times over an extremely long period of evolution (230 million years; Ma). It also attempts to answer questions as to the selective pressures that led to three-ossicle middle ears and the coiled cochlea. Mammalian middle ears arose de novo, without an intermediate, single-ossicle stage. This event was the result of changes in eating habits of ancestral animals, habits that were unrelated to hearing. The coiled cochlea arose only after 60 Ma of mammalian evolution, driven at least partly by a change in cochlear bone structure that improved impedance matching with the middle ear of that time. This change only occurred in the ancestors of therian mammals and not in other mammalian lineages. There is no single constellation of structural features of the auditory periphery that characterizes all mammals and not even all modern mammals.

  5. [The reasonable use of right ventricular protection strategy in right ventricular outflow tract reconstruction].

    Science.gov (United States)

    Zhang, Y; Yuan, H Y; Liu, X B; Wen, S S; Xu, G; Cui, H J; Zhuang, J; Chen, J M

    2018-06-01

    As a result of right ventricular outflow tract reconstruction, which is the important and basic step of complex cardiac surgery, the blood flow of right ventricular outflow tract is unobstructed, while pulmonary valve regurgitation and right heart dysfunction could be happened. These problems are often ignored in early days, more and more cases of right heart dysfunction need clinical intervention, which is quite difficult and less effective. How to protect effectively the right ventricular function is the focus. At present main methods to protect the right ventricular function include trying to avoid or reduce length of right ventricular incision, reserving or rebuilding the function of the pulmonary valve, using growth potential material for surgery. The protection of the right ventricular function is a systemic project, it involves many aspects, single measures is difficult to provide complete protection, only the comprehensive use of various protection strategy, can help to improve the long-term prognosis.

  6. Burned out myocardium in biventricular hypertrophic cardiomyopathy presenting with congestive heart failure: Importance of ECG changes

    Directory of Open Access Journals (Sweden)

    Christer Backman

    2014-01-01

    Full Text Available A 60 year old man was found to have a heart murmur and ECG features of ventricular hypertrophy on a medical check up for military recruitment at age of 20, despite having swimming as the only exercise. His mother had 3 survived children out of 9 pregnancies.

  7. Myocardial Positive Pre-ejection Velocity Accurately Detects Presence of Viable Myocardium, Predicts Recovery of Left Ventricular Function and Bears a Prognostic Value after Surgical Revasculariazation

    Czech Academy of Sciences Publication Activity Database

    Pěnička, P.; Toušek, P.; de Bruyne, B.; Wijns, W.; Lang, O.; Madaric, J.; Vanderhyden, M.; Tintěra, J.; Malý, Marek; Widimský, P.; Bartůněk, J.

    2007-01-01

    Roč. 28, č. 11 (2007), s. 1366-1373 ISSN 0195-668X Source of funding: V - iné verejné zdroje Keywords : tissue Doppler imaging * viability * coronary disease * echocardiography * bypass Subject RIV: FA - Cardiovascular Disease s incl. Cardiotharic Surgery Impact factor: 7.924, year: 2007

  8. Surgical manipulation of mammalian embryos in vitro.

    Science.gov (United States)

    Naruse, I; Keino, H; Taniguchi, M

    1997-04-01

    Whole-embryo culture systems are useful in the fields of not only embryology but also teratology, toxicology, pharmacology, and physiology. Of the many advantages of whole-embryo culture, we focus here on the surgical manipulation of mammalian embryos. Whole-embryo culture allows us to manipulate mammalian embryos, similarly to fish, amphibian and avian embryos. Many surgical experiments have been performed in mammalian embryos in vitro. Such surgical manipulation alters the destiny of morphogenesis of the embryos and can answer many questions concerning developmental issues. As an example of surgical manipulation using whole-embryo culture systems, one of our experiments is described. Microsurgical electrocauterization of the deep preaxial mesodermal programmed cell death zone (fpp) in the footplate prevented the manifestation of polydactyly in genetic polydactyly mouse embryos (Pdn/Pdn), in which fpp was abolished.

  9. Mammalian diversity: gametes, embryos and reproduction.

    Science.gov (United States)

    Behringer, Richard R; Eakin, Guy S; Renfree, Marilyn B

    2006-01-01

    The class Mammalia is composed of approximately 4800 extant species. These mammalian species are divided into three subclasses that include the monotremes, marsupials and eutherians. Monotremes are remarkable because these mammals are born from eggs laid outside of the mother's body. Marsupial mammals have relatively short gestation periods and give birth to highly altricial young that continue a significant amount of 'fetal' development after birth, supported by a highly sophisticated lactation. Less than 10% of mammalian species are monotremes or marsupials, so the great majority of mammals are grouped into the subclass Eutheria, including mouse and human. Mammals exhibit great variety in morphology, physiology and reproduction. In the present article, we highlight some of this remarkable diversity relative to the mouse, one of the most widely used mammalian model organisms, and human. This diversity creates challenges and opportunities for gamete and embryo collection, culture and transfer technologies.

  10. Surgery for ventricular tachycardia in patients undergoing surgical ventricular restoration: the Karolinska approach.

    Science.gov (United States)

    Sartipy, Ulrik; Albåge, Anders; Insulander, Per; Lindblom, Dan

    2007-09-01

    This article presents a review on the efficacy of surgical ventricular restoration and direct surgery for ventricular tachycardia in patients with left ventricular aneurysm or dilated ischemic cardiomyopathy. The procedure includes a non-electrophysiologically guided subtotal endocardiectomy and cryoablation in addition to endoventricular patch plasty of the left ventricle. Coronary artery bypass surgery and mitral valve repair are performed concomitantly as needed. In our experience, this procedure yielded a 90% success rate in terms of freedom from spontaneous ventricular tachycardia, with an early mortality rate of 3.8%. A practical guide to the pre- and postoperative management of these patients is provided.

  11. Right Ventricular Endomyocardial Fibrosis Presenting With Ventricular Tachycardia And Apical Thrombus - An Interesting Presentation

    Directory of Open Access Journals (Sweden)

    Amitesh Aggarwal

    2009-11-01

    Full Text Available Endomyocardial fibrosis is a progressive disease of unknown origin affecting children and young adults. It involves inflow portion of right and/or left ventricle and apex. It may be associated with thrombus. Literature regarding right ventricular endomyocardial fibrosis with thrombus is scarce. Here we report a rare case of right ventricular endomyocardial fibrosis presenting as ventricular tachycardia and echocardiographic evidence of apical thrombus. Interestingly there was no pulmonary involvement or evidence of deep venous thrombosis. This case also underscores the importance of urgent echocardiography in diagnosis of obscure cases of ventricular tachycardia.

  12. Left ventricular function in patients with ventricular arrhythmias and aortic valve disease

    International Nuclear Information System (INIS)

    Santinga, J.T.; Kirsh, M.M.; Brady, T.J.; Thrall, J.; Pitt, B.

    1983-01-01

    Forty patients having aortic valve replacement were evaluated preoperatively for ventricular arrhythmia and left ventricular ejection fraction. Arrhythmias were classified as complex or simple using the Lown criteria on the 24-hour ambulatory electrocardiogram; ejection fractions were determined by radionuclide gated blood pool analysis and contrast angiography. The ejection fractions determined by radionuclide angiography were 59.1 +/- 13.1% for 26 patients with simple or no ventricular arrhythmias, and 43.9 +/- 20.3% for 14 patients with complex ventricular arrhythmias (p less than 0.01). Ejection fractions determined by angiography, available for 31 patients, were also lower in patients with complex ventricular arrhythmias (61.1 +/- 16.3% versus 51.4 +/- 13.4%; p less than 0.05). Seven of 9 patients showing conduction abnormalities on the electrocardiogram had complex ventricular arrhythmias. Eight of 20 patients with aortic stenosis had complex ventricular arrhythmias, while 2 of 13 patients with aortic insufficiency had such arrhythmias. It is concluded that decreased left ventricular ejection fraction, intraventricular conduction abnormalities, and aortic stenosis are associated with an increased frequency of complex ventricular arrhythmias in patients with aortic valve disease

  13. Rest and exercise ventricular function in adults with congenital ventricular septal defects

    International Nuclear Information System (INIS)

    Jablonsky, G.; Hilton, J.D.; Liu, P.P.; Morch, J.E.; Druck, M.N.; Bar-Shlomo, B.Z.; McLaughlin, P.R.

    1983-01-01

    Rest and exercise right and left ventricular function were compared using equilibrium gated radionuclide angiography in 19 normal sedentary control subjects and 34 patients with hemodynamically documented congenital ventricular septal defect (VSD). Gated radionuclide angiography was performed at rest and during each level of graded supine bicycle exercise to fatigue. Heart rate, blood pressure, maximal work load achieved, and right and left ventricular ejection fractions were assessed. The control subjects demonstrated an increase in both the left and right ventricular ejection fractions with exercise. All study groups failed to demonstrate an increase in ejection fraction in either ventricle with exercise. Furthermore, resting left ventricular ejection fraction in Groups 2 and 3 was lower than that in the control subjects and resting right ventricular ejection fraction was lower in Group 3 versus control subjects. Thus left and right ventricular function on exercise were abnormal in patients with residual VSD as compared with control subjects; rest and exercise left ventricular ejection fractions remained abnormal despite surgical closure of VSD in the remote past; resting left and right ventricular function was abnormal in patients with Eisenmenger's complex; lifelong volume overload may be detrimental to myocardial function

  14. Cerebroventricular Microinjection (CVMI) into Adult Zebrafish Brain Is an Efficient Misexpression Method for Forebrain Ventricular Cells

    Science.gov (United States)

    Kizil, Caghan; Brand, Michael

    2011-01-01

    The teleost fish Danio rerio (zebrafish) has a remarkable ability to generate newborn neurons in its brain at adult stages of its lifespan-a process called adult neurogenesis. This ability relies on proliferating ventricular progenitors and is in striking contrast to mammalian brains that have rather restricted capacity for adult neurogenesis. Therefore, investigating the zebrafish brain can help not only to elucidate the molecular mechanisms of widespread adult neurogenesis in a vertebrate species, but also to design therapies in humans with what we learn from this teleost. Yet, understanding the cellular behavior and molecular programs underlying different biological processes in the adult zebrafish brain requires techniques that allow manipulation of gene function. As a complementary method to the currently used misexpression techniques in zebrafish, such as transgenic approaches or electroporation-based delivery of DNA, we devised a cerebroventricular microinjection (CVMI)-assisted knockdown protocol that relies on vivo morpholino oligonucleotides, which do not require electroporation for cellular uptake. This rapid method allows uniform and efficient knockdown of genes in the ventricular cells of the zebrafish brain, which contain the neurogenic progenitors. We also provide data on the use of CVMI for growth factor administration to the brain – in our case FGF8, which modulates the proliferation rate of the ventricular cells. In this paper, we describe the CVMI method and discuss its potential uses in zebrafish. PMID:22076157

  15. Ventricular repolarization measures for arrhythmic risk stratification

    Institute of Scientific and Technical Information of China (English)

    Francesco Monitillo; Marta Leone; Caterina Rizzo; Andrea Passantino; Massimo Iacoviello

    2016-01-01

    Ventricular repolarization is a complex electrical phenomenon which represents a crucial stage in electrical cardiac activity. It is expressed on the surface electrocardiogram by the interval between the start of the QRS complex and the end of the T wave or U wave(QT). Several physiological, pathological and iatrogenic factors can influence ventricular repolarization. It has been demonstrated that small perturbations in this process can be a potential trigger of malignant arrhythmias, therefore the analysis of ventricular repolarization represents an interesting tool to implement risk stratification of arrhythmic events in different clinical settings. The aim of this review is to critically revise the traditional methods of static analysis of ventricular repolarization as well as those for dynamic evaluation, their prognostic significance and the possible application in daily clinical practice.

  16. Acoustophoretic Synchronization of Mammalian Cells in Microchannels

    DEFF Research Database (Denmark)

    Thévoz, P.; Adams, J.D.; Shea, H.

    2010-01-01

    We report the first use of ultrasonic standing waves to achieve cell cycle phase synchronization in mammalian cells in a high-throughput and reagent-free manner. The acoustophoretic cell synchronization (ACS) device utilizes volume-dependent acoustic radiation force within a microchannel to selec......We report the first use of ultrasonic standing waves to achieve cell cycle phase synchronization in mammalian cells in a high-throughput and reagent-free manner. The acoustophoretic cell synchronization (ACS) device utilizes volume-dependent acoustic radiation force within a microchannel...

  17. DNA repair in non-mammalian animals

    International Nuclear Information System (INIS)

    Mitani, Hiroshi

    1984-01-01

    Studies on DNA repair have been performed using microorganisms such as Escherichia coli and cultured human and mammalian cells. However, it is well known that cultured organic cells differ from each other in many respects, although DNA repair is an extremely fundamental function of organisms to protect genetic information from environmental mutagens such as radiation and 0 radicals developing in the living body. To answer the question of how DNA repair is different between the animal species, current studies on DNA repair of cultured vertebrate cells using the methods similar to those in mammalian experiments are reviewed. (Namekawa, K.)

  18. Salbutamol Abuse is Associated with Ventricular Fibrillation

    Directory of Open Access Journals (Sweden)

    Emin UYSAL

    2015-06-01

    Full Text Available SUMMARY: Salbutamol-induced cardiac complications are well-established. Herein, we describe a case of a 24-year female who was admitted to the emergency department because of a suicide attempt with salbutamol (76 mg. Salbutamol abuse induced the development of supraventricular tachycardia and ventricular fibrillation. Regular sinus rhythm was restored with defibrillation. The hypokalemic patient who stayed in the intensive care unit was discharged after 48 hours of hospitalization. Key words: Salbutamol, suicide, ventricular fibrillation

  19. Clustering Of Left Ventricular Wall Motion Patterns

    Science.gov (United States)

    Bjelogrlic, Z.; Jakopin, J.; Gyergyek, L.

    1982-11-01

    A method for detection of wall regions with similar motion was presented. A model based on local direction information was used to measure the left ventricular wall motion from cineangiographic sequence. Three time functions were used to define segmental motion patterns: distance of a ventricular contour segment from the mean contour, the velocity of a segment and its acceleration. Motion patterns were clustered by the UPGMA algorithm and by an algorithm based on K-nearest neighboor classification rule.

  20. Ventricular tachycardia induced by weight loss pills

    DEFF Research Database (Denmark)

    Pareek, Manan; Hansson, Nils Henrik; Grove, Erik Lerkevang

    2013-01-01

    A previously healthy 29-year-old man was admitted with palpitations, dizziness, and near-syncope after he had recently started taking weight loss pills purchased on the internet. The pills contained caffeine and ephedrine. An electrocardiogram and telemetry revealed multiple episodes of non......-sustained monomorphic ventricular tachycardia, which was successfully treated with amiodarone. In conclusion, unauthorized weight loss pills can be harmful. In particular, ephedrine-containing drugs carry a risk of ventricular tachycardia and should be discouraged....

  1. Nitrate administration increases blood flow in dysfunctional but viable myocardium, leading to improved assessment of myocardial viability : A PET study

    NARCIS (Netherlands)

    Slart, Riemer H. J. A.; Agool, Ali; van Veldhuisen, Dirk J.; Dierckx, Rudi A.; Bax, Jeroen J.

    SPECT with Tc-99m-labeled agents is better able to detect viability after nitrate administration. Nitrates induce vasoclilation and may increase blood flow to severely hypoperfused but viable myocardium, thereby enhancing tracer delivery and improving the detection of viability. Quantitative data on

  2. Collateral circulation as a marker of the presence of viable myocardium in patients with recent myocardial infarction

    International Nuclear Information System (INIS)

    Fujita, M.; Ohno, A.; Wada, O.; Miwa, K.; Nozawa, T.; Yamanishi, K.; Sasayama, S.

    1991-01-01

    The relationship between the presence of viable myocardium and the extent of coronary collateral circulation to the infarct area was evaluated in 20 patients with a recent anterior myocardial infarction who had complete obstruction of the left anterior descending coronary artery. The viability of myocardial tissue was assessed by exercise thallium-201 myocardial scintigraphy, and the collateral circulation was angiographically evaluated by means of a collateral index ranging from 0 to 3. Patients were divided into two groups according to the presence (group 1, n = 10) or absence (group 2, n = 10) of viable myocardium in the perfusion territory of the infarct-related artery. The collateral index in group 1 was 2.5 ± 0.5 (SD), which was significantly higher than the 0.7 ± 0.8 in group 2. These findings indicate that the presence of ischemic but viable myocardium is intimately related to the development of collateral circulation in patients with myocardial infarction, and the existence of well-developed collateral channels predicts the presence of viable myocardium in the infarct area

  3. Volume of myocardium perfused by coronary artery branches as estimated from 3D micro-CT images of rat hearts

    Science.gov (United States)

    Lund, Patricia E.; Naessens, Lauren C.; Seaman, Catherine A.; Reyes, Denise A.; Ritman, Erik L.

    2000-04-01

    Average myocardial perfusion is remarkably consistent throughout the heart wall under resting conditions and the velocity of blood flow is fairly reproducible from artery to artery. Based on these observations, and the fact that flow through an artery is the product of arterial cross-sectional area and blood flow velocity, we would expect the volume of myocardium perfused to be proportional to the cross-sectional area of the coronary artery perfusing that volume of myocardium. This relationship has been confirmed by others in pigs, dogs and humans. To test the body size-dependence of this relationship we used the hearts from rats, 3 through 25 weeks of age. The coronary arteries were infused with radiopaque microfil polymer and the hearts scanned in a micro- CT scanner. Using these 3D images we measured the volume of myocardium and the arterial cross-sectional area of the artery that perfused that volume of myocardium. The average constant of proportionality was found to be 0.15 +/- 0.08 cm3/mm2. Our data showed no statistically different estimates of the constant of proportionality in the rat hearts of different ages nor between the left and right coronary arteries. This constant is smaller than that observed in large animals and humans, but this difference is consistent with the body mass-dependence on metabolic rate.

  4. Capillary transfer constant of Gd-DTPA in the myocardium at rest and during vasodilation assessed by MRI

    DEFF Research Database (Denmark)

    Fritz-Hansen, T; Rostrup, Egill; Søndergaard, Lise

    1998-01-01

    The purpose of this study was to determine whether the capillary transfer constant (Ki) of gadolinium-DTPA was sensitive to perfusion changes and whether ischemic regions in the myocardium could be identified using the modified Kety formula. Ki was measured at rest and during dipyridamole...

  5. Troponin and anti-troponin autoantibody levels in patients with ventricular noncompaction.

    Directory of Open Access Journals (Sweden)

    Hatice Betül Erer

    Full Text Available Ventricular hypertrabeculation/noncompaction is a morphologic and functional anomaly of myocardium characterized by prominent trabeculae accompanied by deep recessus. Dilated cardiomyopathy with left ventricular failure is observed in these patients, while the cause or pathophysiologic nature of this complication is not known. Anti-troponin antibodies are formed against circulating cardiac troponins after an acute coronary event or conditions associated with chronic myocyte necrosis, such as dilated cardiomyopathy. In present study, we aimed to investigate cardiac troponins and anti troponin autoantibodies in ventricular noncompaction/hypertrabeculation patients with/without reduced ejection fraction. A total of 50 patients with ventricular noncompaction and 23 healthy volunteers were included in this study. Noncompaction/hypertrabeculation was diagnosed with two-dimensional echocardiography using appropriate criteria. Depending on ejection fraction, patients were grouped into noncompaction with preserved EF (LVEF >50%, n = 24 and noncompaction with reduced EF (LVEF <35%, n = 26 groups. Troponin I, troponin T, anti-troponin I IgM and anti-troponin T IgM were measured with sandwich immunoassay method using a commercially available kit. Patients with noncompaction had significantly higher troponin I (28.98±9.21 ng/ml in NCNE group and 28.11±10.42 ng/ml in NCLE group, troponin T (22.17±6.97 pg/ml in NCNE group and 22.78±7.76 pg/ml in NCLE group and antitroponin I IgM (1.92±0.43 µg/ml in NCNE group and 1.79±0.36 µg/ml in NCLE group levels compared to control group, while antitroponin T IgM and IgG were only elevated in patients with noncompaction and reduced EF (15.81±6.52 µg/ml for IgM and 16.46±6.25 µg/ml for IgG. Elevated cardiac troponins and anti-troponin I autoantibodies were observed in patients with noncompaction preceding the decline in systolic function and could indicate ongoing myocardial damage in these patients.

  6. Troponin and Anti-Troponin Autoantibody Levels in Patients with Ventricular Noncompaction

    Science.gov (United States)

    Erer, Hatice Betül; Güvenç, Tolga Sinan; Kemik, Ahu Sarbay; Yılmaz, Hale Yaka; Kul, Şeref; Altay, Servet; Sayar, Nurten; Kaya, Yüksel; Eren, Mehmet

    2013-01-01

    Ventricular hypertrabeculation/noncompaction is a morphologic and functional anomaly of myocardium characterized by prominent trabeculae accompanied by deep recessus. Dilated cardiomyopathy with left ventricular failure is observed in these patients, while the cause or pathophysiologic nature of this complication is not known. Anti-troponin antibodies are formed against circulating cardiac troponins after an acute coronary event or conditions associated with chronic myocyte necrosis, such as dilated cardiomyopathy. In present study, we aimed to investigate cardiac troponins and anti troponin autoantibodies in ventricular noncompaction/hypertrabeculation patients with/without reduced ejection fraction. A total of 50 patients with ventricular noncompaction and 23 healthy volunteers were included in this study. Noncompaction/hypertrabeculation was diagnosed with two-dimensional echocardiography using appropriate criteria. Depending on ejection fraction, patients were grouped into noncompaction with preserved EF (LVEF >50%, n = 24) and noncompaction with reduced EF (LVEF <35%, n = 26) groups. Troponin I, troponin T, anti-troponin I IgM and anti-troponin T IgM were measured with sandwich immunoassay method using a commercially available kit. Patients with noncompaction had significantly higher troponin I (28.98±9.21 ng/ml in NCNE group and 28.11±10.42 ng/ml in NCLE group), troponin T (22.17±6.97 pg/ml in NCNE group and 22.78±7.76 pg/ml in NCLE group) and antitroponin I IgM (1.92±0.43 µg/ml in NCNE group and 1.79±0.36 µg/ml in NCLE group) levels compared to control group, while antitroponin T IgM and IgG were only elevated in patients with noncompaction and reduced EF (15.81±6.52 µg/ml for IgM and 16.46±6.25 µg/ml for IgG). Elevated cardiac troponins and anti-troponin I autoantibodies were observed in patients with noncompaction preceding the decline in systolic function and could indicate ongoing myocardial damage in these patients. PMID:23469039

  7. Experimental study of 31P MR spectroscopy in vitro canine myocardium

    International Nuclear Information System (INIS)

    Gao Fabao; Zhao Haitao; Suo Liping; Zhang Yushun; Fang Hong; Huang Zhilan

    1999-01-01

    Objective: To conduct a dynamic survey of the metabolism of high-energy phosphates in myocardium in order to define, the relationship between the changes in myocardial energy metabolism and the duration of ischemia. Methods: A dynamic survey of isolated heart of 8 dogs was done with the use of 31 P MRS. Results: Myocardial PCr level decreased rapidly after the heart was isolated and was reduced to zero in 2-3 hours. ATP level diminished progressively to its depletion at 6 hours following isolation. Conclusions: After the heart was isolated, the PCr level rapidly decreased and was reduced to zero in 2-3 hours whereas ATP was not depleted until 4-6 hours after isolation. The ATP level remained within normal limits as long as PCr had not been depleted

  8. New perspectives in the treatment of damaged myocardium using autologous skeletal myoblasts

    International Nuclear Information System (INIS)

    Rigatelli, Gianluca; Rossini, Katia; Vindigni, Vincenzo; Mazzoleni, Francesco; Rigatelli, Giorgio; Carraro, Ugo

    2004-01-01

    Autologous skeletal myoblast transplantation may be used to ameliorate the healing process following myocardium infarct and, hopefully, cardiomyopathies. Despite successful animal experimentation, several issues need to be addressed in clinical settings, i.e., the impact of the delivery route, the extent of short- and long-term survival, and differentiation of the injected skeletal myoblasts. The authors offer some new hypotheses resulting from basic research, i.e., where and when to inject the myogenic cells, whatever their source, how to decrease new myofiber atrophy and improve their regeneration. Although these new hypotheses still need to be tested in humans, they may be decisive for future experimental studies and will lead to making endovascular cell implantation a more effective way to treat ischemic heart disease and failure

  9. Comparison of exercise and pharmacologic stress in myocardium perfusion imaging for CHD

    International Nuclear Information System (INIS)

    Li Zebo; Zheng Kangni; Cheng Xiaorui; Liu Hui; Cheng Yihai

    1995-01-01

    In order to provide a proper stress test, exercise, dipyridamole and ATP stress were compared. Three modalities were compared with respect to the detecting rate, methodology, hemodynamic and side effects. There are no significant differences in their ability of detecting coronary heart disease (CHD) (P>0.05). Exercise stress causes an increase in heart rate, blood pressure and myocardium oxygen consumption. Pharmacologic stress cause a slight increase in heart rate, but a decrease in blood pressure (P<0.01). Exercise stress is a basic method with good image quality, but it needs a special equipment. Pharmacologic stress is an easier, cheaper and safer method, particularly useful for patients unable to perform exercise test

  10. Myocardium at risk assessed by electrocardiographic scores and cardiovascular magnetic resonance - a MITOCARE substudy

    DEFF Research Database (Denmark)

    Sejersten, Maria; Fakhri, Yama; Pape, Marianne

    2017-01-01

    Introduction The myocardium at risk (MaR) represents the quantitative ischemic area destined to myocardial infarction (MI) if no reperfusion therapy is initiated. Different ECG scores for MaR have been developed, but there is no consensus as to which should be preferred. Objective Comparisons...... of ECG scores and Cardiac Magnetic Resonance (CMR) for determining MaR. Methods MaR was determined by 3 different ECG scores, and by CMR in ST-segment elevation MI (STEMI) patients from the MITOCARE cardioprotection trial. The Aldrich score (AL) is based on the number of leads with ST-elevation...... for anterior MI and the sum of ST-segment elevation for inferior MI on the admission ECG. The van Hellemond score (VH) considers both the ischemic and infarcted component of the MaR by adding the AL and the QRS score, which is an estimate of final infarct size. The Hasche score is based on the maximal possible...

  11. Isolated noncompaction of myocardium associated with calcification in the interventricular septum.

    Science.gov (United States)

    Nil, M; Mori, K; Yuasa, Y; Ichida, F

    2003-01-01

    We describe a 12-year-old male with isolated noncompaction of the myocardium and associated abnormal calcification in the basal interventricular septum, and we present a review of the literature. The patient has been healthy and free of symptoms. The electrocardiogram showed abnormal Q waves in III, V1, V2, and ST elevation in V1-V3. Exercise testing demonstrated ST depression in V4 and V5. Myocardial scintigraphic examination showed a regional reduction in iodine-1,2,3-beta-methyl-iodophenylpentadecanoic acid uptake in the basal interventricular septum. Since coronary angiography demonstrated normal coronary vessels and the trabeculations were not prominent in this region, we hypothesize that coronary microcirculatory dysfunction may cause subendocardial infarction associated with calcification in the same area.

  12. Fractional flow reserve guided percutaneous coronary intervention results in reduced ischemic myocardium and improved outcomes.

    Science.gov (United States)

    Sawant, Abhishek C; Bhardwaj, Aishwarya; Banerjee, Kinjal; Jobanputra, Yash; Kumar, Arnav; Parikh, Parth; Kandregula, Krishna C; Poddar, Kanhaiya; Ellis, Stephen G; Nair, Ravi; Corbelli, John; Kapadia, Samir

    2018-02-06

    To determine if fractional flow reserve guided percutaneous coronary intervention (FFR-guided PCI) is associated with reduced ischemic myocardium compared with angiography-guided PCI. Although FFR-guided PCI has been shown to improve outcomes, it remains unclear if it reduces the extent of ischemic myocardium at risk compared with angiography-guided PCI. We evaluated 380 patients (190 FFR-guided PCI cases and 190 propensity-matched controls) who underwent PCI from 2009 to 2014. Clinical, laboratory, angiographic, stress testing, and major adverse cardiac events [MACE] (all-cause mortality, recurrence of MI requiring PCI, stroke) data were collected. Mean age was 63 ± 11 years; the majority of patients were males (76%) and Caucasian (77%). Median duration of follow up was 3.4 [Range: 1.9, 5.0] years. Procedural complications including coronary dissection (2% vs. 0%, P = .12) and perforation (0% vs. 0%, P = 1.00) were similar between FFR-guided and angiography-guided PCI patients. FFR-guided PCI patients had lower unadjusted (14.7% vs. 23.2%, P = .04) and adjusted [OR = 0.58 (95% CI: 0.34-0.98)] risk of repeat revascularization at one year. FFR-guided PCI patients were less likely (23% vs. 32%, P = .02) to have ischemia and had lower (5.9% vs. 21.1%, P guided PCI, FFR-guided PCI results in less repeat revascularization and a lower incidence of post PCI ischemia translating into improved survival, without an increase in complications. © 2018 Wiley Periodicals, Inc.

  13. Constitutive activation of Nrf2 induces a stable reductive state in the mouse myocardium

    Directory of Open Access Journals (Sweden)

    Gobinath Shanmugam

    2017-08-01

    Full Text Available Redox homeostasis regulates key cellular signaling pathways in both physiology and pathology. The cell's antioxidant response provides a defense against oxidative stress and establishes a redox tone permissive for cell signaling. The molecular regulation of the well-known Keap1/Nrf2 system acts as sensor responding to changes in redox homeostasis and is poorly studied in the heart. Importantly, it is not yet known whether Nrf2 alone can serve as a master regulator of cellular redox homeostasis without compensation of the transcriptional regulation of antioxidant response element (ARE genes through alternate mechanisms. Here, we addressed this question using cardiac-specific transgenic expression at two different levels of constitutively active nuclear erythroid related factor 2 (caNrf2 functioning independently of Keap1. The caNrf2 mice showed augmentation of glutathione (GSH, the key regulator of the cellular thiol redox state. The Trans-AM assay for Nrf2-binding to the antioxidant response element (ARE showed a dose-dependent increase associated with upregulation of several major antioxidant genes and proteins. This was accompanied by a significant decrease in dihydroethidium staining and malondialdehyde (MDA in the caNrf2-TG mice myocardium. Interestingly, caNrf2 gene-dosage dependent redox changes were noted resulting in generation of a multi-stage model of pro-reductive and reductive conditions in the myocardium of TG-low and TG-high mice, respectively. These data clearly show that Nrf2 levels alone are capable of serving as the master regulator of the ARE. These models provide an important platform to investigate the impact of the Nrf2 system independent of the need to regulate the activity of Keap1 and the consequent exposure to pro-oxidants or electrophiles, which have numerous off-target effects.

  14. Retention and clearance of C-11 palmitic acid in ischemic and reperfused canine myocardium

    International Nuclear Information System (INIS)

    Schwaiger, M.; Schelbert, H.R.; Keen, R.; Vinten-Johansen, J.; Hansen, H.; Selin, C.; Barrio, J.; Huang, S.C.; Phelps, M.E.

    1985-01-01

    Free fatty acids are the major energy source for cardiac muscle. Oxidation of fatty acid decreases or even ceases during ischemia. Its recovery after transient ischemia remains largely unexplored. Using intracoronary carbon-11 palmitic acid as a tracer of myocardial fatty acid metabolism in an open chest dog model, retention and clearance of tracer in myocardium were evaluated at control, during ischemia and after reperfusion following a 20 minute occlusion of the left anterior descending coronary artery. Myocardial C-11 time-activity curves were analyzed with biexponential curve-fitting routines yielding fractional distribution and clearance half-times of C-11 palmitic acid in myocardial tissue. In animals with permanent occlusion and intracoronary injection of C-11 palmitic acid distal to the occlusion site, the relative size and half-time of the early clearance curve component differed markedly from control values and did not change with ongoing ischemia. Conversely, in animals with only 20 minutes of coronary occlusion, the relative size of the early C-11 clearance phase was still significantly depressed at 20 and 90 minutes of reperfusion but returned to control level at 180 minutes. Tissue C-11 clearance half-times remained significantly prolonged throughout the reperfusion period. Regional function in reperfused myocardium monitored with ultrasonic crystals recovered slowly and was still less than control after 3 hours of reperfusion. The data indicate that after transient ischemia, myocardial fatty acid metabolism fails to recover immediately. Because the metabolic recovery occurs in parallel with recovery of regional function, C-11 palmitic acid in conjunction with positron tomography may be useful for studying regional fatty acid metabolism noninvasively after an ischemic injury, and may be helpful in identifying reversible tissue injury

  15. Hyperthyroidism causes mechanical insufficiency of myocardium with possibly increased SR Ca2+-ATPase activity.

    Science.gov (United States)

    Takeuchi, Koh; Minakawa, M; Otaki, M; Odagiri, S; Itoh, K; Murakami, A; Yaku, H; Kitamura, N

    2003-12-01

    Hyperthyroidism is known to affect multiple organ functions, and thyroid hormone has been known to improve myocardial function in a failing heart. The purpose of this study is to elucidate the functional and metabolic effects of thyroid hormone on myocardium in a rat model exposed to long-term excess thyroid hormone, particularly focusing on the SR Ca(2+)-ATPase (SERCA2) function. 3,5,3'-Triiodo-L-thyronine (T3), or the vehicle, was subcutaneously given for 4 weeks (T3 and control [C] group). Bolus I.V. Thapsigargin (TG) was used to test the SERCA2 function (C-TG and T3-TG) in Langendorff perfused heart. Myocardial functions such as LV-developed pressure (LVDP; mmHg), +/- dP/dt (mmHg/s), tau (ms), and oxygen consumption (MVO(2); ml/min/g wt) were measured. SERCA2 and GLUT4 protein level were also evaluated by Western immunoblotting. Left ventricle to body weight (LV/BW) ratio was significantly higher in the T3 group. Both negative dP/dt and tau were significantly decreased by TG. It is interesting that the decrement of negative dP/dt and tau attained by TG was significantly larger in the hyperthyroid group (T3-TG) than in a normal heart (C-TG). SERCA2 and GLUT4 protein levels were not significantly different between control and the T3 group. We conclude that prolonged exposure to thyroid hormone causes hypertrophy of the myocardium and an augmentation of the SR Ca(2+) ATPase activity. Care must be taken in hyperthyroid heart during the ischemia-reperfusion process where the SRECA2 function is inhibited.

  16. Gene Expression Networks in the Murine Pulmonary Myocardium Provide Insight into the Pathobiology of Atrial Fibrillation

    Directory of Open Access Journals (Sweden)

    Jordan K. Boutilier

    2017-09-01

    Full Text Available The pulmonary myocardium is a muscular coat surrounding the pulmonary and caval veins. Although its definitive physiological function is unknown, it may have a pathological role as the source of ectopic beats initiating atrial fibrillation. How the pulmonary myocardium gains pacemaker function is not clearly defined, although recent evidence indicates that changed transcriptional gene expression networks are at fault. The gene expression profile of this distinct cell type in situ was examined to investigate underlying molecular events that might contribute to atrial fibrillation. Via systems genetics, a whole-lung transcriptome data set from the BXD recombinant inbred mouse resource was analyzed, uncovering a pulmonary cardiomyocyte gene network of 24 transcripts, coordinately regulated by chromosome 1 and 2 loci. Promoter enrichment analysis and interrogation of publicly available ChIP-seq data suggested that transcription of this gene network may be regulated by the concerted activity of NKX2-5, serum response factor, myocyte enhancer factor 2, and also, at a post-transcriptional level, by RNA binding protein motif 20. Gene ontology terms indicate that this gene network overlaps with molecular markers of the stressed heart. Therefore, we propose that perturbed regulation of this gene network might lead to altered calcium handling, myocyte growth, and contractile force contributing to the aberrant electrophysiological properties observed in atrial fibrillation. We reveal novel molecular interactions and pathways representing possible therapeutic targets for atrial fibrillation. In addition, we highlight the utility of recombinant inbred mouse resources in detecting and characterizing gene expression networks of relatively small populations of cells that have a pathological significance.

  17. Quantitative shear wave imaging optical coherence tomography for noncontact mechanical characterization of myocardium

    Science.gov (United States)

    Wang, Shang; Lopez, Andrew L.; Morikawa, Yuka; Tao, Ge; Li, Jiasong; Larina, Irina V.; Martin, James F.; Larin, Kirill V.

    2015-03-01

    Optical coherence elastography (OCE) is an emerging low-coherence imaging technique that provides noninvasive assessment of tissue biomechanics with high spatial resolution. Among various OCE methods, the capability of quantitative measurement of tissue elasticity is of great importance for tissue characterization and pathology detection across different samples. Here we report a quantitative OCE technique, termed quantitative shear wave imaging optical coherence tomography (Q-SWI-OCT), which enables noncontact measurement of tissue Young's modulus based on the ultra-fast imaging of the shear wave propagation inside the sample. A focused air-puff device is used to interrogate the tissue with a low-pressure short-duration air stream that stimulates a localized displacement with the scale at micron level. The propagation of this tissue deformation in the form of shear wave is captured by a phase-sensitive OCT system running with the scan of the M-mode imaging over the path of the wave propagation. The temporal characteristics of the shear wave is quantified based on the cross-correlation of the tissue deformation profiles at all the measurement locations, and linear regression is utilized to fit the data plotted in the domain of time delay versus wave propagation distance. The wave group velocity is thus calculated, which results in the quantitative measurement of the Young's modulus. As the feasibility demonstration, experiments are performed on tissuemimicking phantoms with different agar concentrations and the quantified elasticity values with Q-SWI-OCT agree well with the uniaxial compression tests. For functional characterization of myocardium with this OCE technique, we perform our pilot experiments on ex vivo mouse cardiac muscle tissues with two studies, including 1) elasticity difference of cardiac muscle under relaxation and contract conditions and 2) mechanical heterogeneity of the heart introduced by the muscle fiber orientation. Our results suggest the

  18. Large right ventricular sinusoids in an infant with aorta-left ventricular tunnel and proximal right coronary artery atresia.

    Science.gov (United States)

    Chen, Peter C; Spinner, Joseph A; Heinle, Jeffrey S

    2018-07-01

    We report a 1-month-old infant diagnosed with an aorta-left ventricular tunnel, ventricular septal defect, and right coronary atresia with right ventricular sinusoids. The patient's anatomy and physiology did not indicate right-ventricular-dependent coronary circulation, and therefore right ventricular decompression could be performed without compromising coronary perfusion during surgical correction. A detailed understanding of the coronary anatomy is critical in managing this defect when coronary anomalies are present.

  19. The Use of β-blockers in Patients with Ventricular Ectopic Heartbeat in the Early and Distant Postinfarction Period

    Directory of Open Access Journals (Sweden)

    N. M. Kulayets

    2017-10-01

    of carvedilol, a slightly less in patients treated with metoprolol and sotalol. Conclusions. Sotalol in patients after ACS has an ability to reduce the ventricular ectopic heartbeat episodes number and prevents life-threatening arrhythmias, provides a permanent and controlled decrease of heart rate, corrects left ventricle (LV contractility and processes of postinfarction remodeling of the heart. When using carvedilol it has been noticed a reduction of LV postinfarction remodeling processes, improvement of contractile function of myocardium, antianginal and antiarrhythmic effects, normalization of heart rate variability, reduction of myocardial ischemia, reduction in sudden cardiac death cases. acute coronary syndrome; ventricular premature complexes; ischemic heart disease; myocardial infarction; sotalol; carvedilol

  20. A promoter-level mammalian expression atlas

    KAUST Repository

    Forest, Alistair R R

    2014-03-26

    Regulated transcription controls the diversity, developmental pathways and spatial organization of the hundreds of cell types that make up a mammal. Using single-molecule cDNA sequencing, we mapped transcription start sites (TSSs) and their usage in human and mouse primary cells, cell lines and tissues to produce a comprehensive overview of mammalian gene expression across the human body. We find that few genes are truly ‘housekeeping’, whereas many mammalian promoters are composite entities composed of several closely separated TSSs, with independent cell-type-specific expression profiles. TSSs specific to different cell types evolve at different rates, whereas promoters of broadly expressed genes are the most conserved. Promoter-based expression analysis reveals key transcription factors defining cell states and links them to binding-site motifs. The functions of identified novel transcripts can be predicted by coexpression and sample ontology enrichment analyses. The functional annotation of the mammalian genome 5 (FANTOM5) project provides comprehensive expression profiles and functional annotation of mammalian cell-type-specific transcriptomes with wide applications in biomedical research.

  1. Endogenous retrovirus sequences expressed in male mammalian ...

    African Journals Online (AJOL)

    Objectives: To review the research findings on the expression of endogenous retroviruses and retroviral-related particles in male mammalian reproductive tissues, and to discuss their possible role in normal cellular events and association with disease conditions in male reproductive tissues. Data sources: Published ...

  2. Locomotor circuits in the mammalian spinal cord

    DEFF Research Database (Denmark)

    Kiehn, Ole

    2006-01-01

    Intrinsic spinal networks, known as central pattern generators (CPGs), control the timing and pattern of the muscle activity underlying locomotion in mammals. This review discusses new advances in understanding the mammalian CPGs with a focus on experiments that address the overall network struct...

  3. A promoter-level mammalian expression atlas

    KAUST Repository

    Forest, Alistair R R; Kawaji, Hideya; Rehli, Michael; Baillie, John Kenneth; De Hoon, Michiel Jl L; Haberle, Vanja; Lassmann, Timo; Kulakovskiy, Ivan V.; Lizio, Marina; Itoh, Masayoshi; Andersson, Robin; Iida, Kei; Ikawa, Tomokatsu; Jankovic, Boris R.; Jia, Hui; Joshi, Anagha Madhusudan; Jurman, Giuseppe; Kaczkowski, Bogumił; Kai, Chieko; Kaida, Kaoru; Kaiho, Ai; Mungall, Christopher J.; Kajiyama, Kazuhiro; Kanamori-Katayama, Mutsumi; Kasianov, Artem S.; Kasukawa, Takeya; Katayama, Shintaro; Kato, Sachi; Kawaguchi, Shuji; Kawamoto, Hiroshi; Kawamura, Yuki I.; Kawashima, Tsugumi; Meehan, Terrence F.; Kempfle, Judith S.; Kenna, Tony J.; Kere, Juha; Khachigian, Levon M.; Kitamura, Toshio; Klinken, Svend Peter; Knox, Alan; Kojima, Miki; Kojima, Soichi; Kondo, Naoto; Schmeier, Sebastian; Koseki, Haruhiko; Koyasu, Shigeo; Krampitz, Sarah; Kubosaki, Atsutaka; Kwon, Andrew T.; Laros, Jeroen F J; Lee, Weonju; Lennartsson, Andreas; Li, Kang; Lilje, Berit; Bertin, Nicolas; Lipovich, Leonard; MacKay-Sim, Alan; Manabe, Riichiroh; Mar, Jessica; Marchand, Benoî t; Mathelier, Anthony; Mejhert, Niklas; Meynert, Alison M.; Mizuno, Yosuke; De Morais, David A Lima; Jø rgensen, Mette Christine; Morikawa, Hiromasa; Morimoto, Mitsuru; Moro, Kazuyo; Motakis, Efthymios; Motohashi, Hozumi; Mummery, Christine L.; Murata, Mitsuyoshi; Nagao-Sato, Sayaka; Nakachi, Yutaka; Nakahara, Fumio; Dimont, Emmanuel; Nakamura, Toshiyuki; Nakamura, Yukio; Nakazato, Kenichi; Van Nimwegen, Erik; Ninomiya, Noriko; Nishiyori, Hiromi; Noma, Shohei; Nozaki, Tadasuke; Ogishima, Soichi; Ohkura, Naganari; Arner, Erik; Ohmiya, Hiroko; Ohno, Hiroshi; Ohshima, Mitsuhiro; Okada-Hatakeyama, Mariko; Okazaki, Yasushi; Orlando, Valerio; Ovchinnikov, Dmitry A.; Pain, Arnab; Passier, Robert C J J; Patrikakis, Margaret; Schmidl, Christian; Persson, Helena A.; Piazza, Silvano; Prendergast, James G D; Rackham, Owen J L; Ramilowski, Jordan A.; Rashid, Mamoon; Ravasi, Timothy; Rizzu, Patrizia; Roncador, Marco; Roy, Sugata; Schaefer, Ulf; Rye, Morten Beck; Saijyo, Eri; Sajantila, Antti; Saka, Akiko; Sakaguchi, Shimon; Sakai, Mizuho; Sato, Hiroki; Satoh, Hironori; Savvi, Suzana; Saxena, Alka; Medvedeva, Yulia; Schneider, Claudio H.; Schultes, Erik A.; Schulze-Tanzil, Gundula G.; Schwegmann, Anita; Sengstag, Thierry; Sheng, Guojun; Shimoji, Hisashi; Shimoni, Yishai; Shin, Jay W.; Simon, Chris M.; Plessy, Charles; Sugiyama, Daisuke; Sugiyama, Takaaki; Suzuki, Masanori; Suzuki, Naoko; Swoboda, Rolf K.; 't Hoen, Peter Ac Chr; Tagami, Michihira; Tagami, Naokotakahashi; Takai, Jun; Tanaka, Hiroshi; Vitezic, Morana; Tatsukawa, Hideki; Tatum, Zuotian; Thompson, Mark; Toyoda, Hiroo; Toyoda, Tetsuro; Valen, Eivind; Van De Wetering, Marc L.; Van Den Berg, Linda M.; Verardo, Roberto; Vijayan, Dipti; Severin, Jessica M.; Vorontsov, Ilya E.; Wasserman, Wyeth W.; Watanabe, Shoko; Wells, Christine A.; Winteringham, Louise Natalie; Wolvetang, Ernst Jurgen; Wood, Emily J.; Yamaguchi, Yoko; Yamamoto, Masayuki; Yoneda, Misako; Semple, Colin Am M; Yonekura, Yohei; Yoshida, Shigehiro; Zabierowski, Susan E.; Zhang, Peter; Zhao, Xiaobei; Zucchelli, Silvia; Summers, Kim M.; Suzuki, Harukazu; Daub, Carsten Olivier; Kawai, Jun; Ishizu, Yuri; Heutink, Peter; Hide, Winston; Freeman, Tom C.; Lenhard, Boris; Bajic, Vladimir B.; Taylor, Martin S.; Makeev, Vsevolod J.; Sandelin, Albin; Hume, David A.; Carninci, Piero; Young, Robert S.; Hayashizaki, Yoshihide Yoshihide; Francescatto, Margherita; Altschuler, Intikhab Alam; Albanese, Davide; Altschule, Gabriel M.; Arakawa, Takahiro; Archer, John A.C.; Arner, Peter; Babina, Magda; Rennie, Sarah; Balwierz, Piotr J.; Beckhouse, Anthony G.; Pradhan-Bhatt, Swati; Blake, Judith A.; Blumenthal, Antje; Bodega, Beatrice; Bonetti, Alessandro; Briggs, James A.; Brombacher, Frank; Burroughs, Alexander Maxwell; Califano, Andrea C.; Cannistraci, Carlo; Carbajo, Daniel; Chen, Yun; Chierici, Marco; Ciani, Yari; Clevers, Hans C.; Dalla, Emiliano; Davis, Carrie Anne; Detmar, Michael J.; Diehl, Alexander D.; Dohi, Taeko; Drablø s, Finn; Edge, Albert SB B; Edinger, Matthias G.; Ekwall, Karl; Endoh, Mitsuhiro; Enomoto, Hideki; Fagiolini, Michela; Fairbairn, Lynsey R.; Fang, Hai; Farach-Carson, Mary Cindy; Faulkner, Geoffrey J.; Favorov, Alexander V.; Fisher, Malcolm E.; Frith, Martin C.; Fujita, Rie; Fukuda, Shiro; Furlanello, Cesare; Furuno, Masaaki; Furusawa, Junichi; Geijtenbeek, Teunis Bh H; Gibson, Andrew P.; Gingeras, Thomas R.; Goldowitz, Dan; Gough, Julian; Guhl, Sven; Guler, Reto; Gustincich, Stefano; Ha, Thomas; Hamaguchi, Masahide; Hara, Mitsuko; Harbers, Matthias; Harshbarger, Jayson; Hasegawa, Akira; Hasegawa, Yuki; Hashimoto, Takehiro; Herlyn, Meenhard F.; Hitchens, Kelly J.; Sui, Shannan J Ho; Hofmann, Oliver M.; Hoof, Ilka; Hori, Fumi; Huminiecki, Łukasz B.

    2014-01-01

    Regulated transcription controls the diversity, developmental pathways and spatial organization of the hundreds of cell types that make up a mammal. Using single-molecule cDNA sequencing, we mapped transcription start sites (TSSs) and their usage in human and mouse primary cells, cell lines and tissues to produce a comprehensive overview of mammalian gene expression across the human body. We find that few genes are truly ‘housekeeping’, whereas many mammalian promoters are composite entities composed of several closely separated TSSs, with independent cell-type-specific expression profiles. TSSs specific to different cell types evolve at different rates, whereas promoters of broadly expressed genes are the most conserved. Promoter-based expression analysis reveals key transcription factors defining cell states and links them to binding-site motifs. The functions of identified novel transcripts can be predicted by coexpression and sample ontology enrichment analyses. The functional annotation of the mammalian genome 5 (FANTOM5) project provides comprehensive expression profiles and functional annotation of mammalian cell-type-specific transcriptomes with wide applications in biomedical research.

  4. Structure and function of mammalian cilia

    DEFF Research Database (Denmark)

    Satir, Peter; Christensen, Søren T

    2008-01-01

    In the past half century, beginning with electron microscopic studies of 9 + 2 motile and 9 + 0 primary cilia, novel insights have been obtained regarding the structure and function of mammalian cilia. All cilia can now be viewed as sensory cellular antennae that coordinate a large number...

  5. Stress induced right ventricular dysfunction: An indication of reversible right ventricular ischaemia

    International Nuclear Information System (INIS)

    Underwood, S.R.; Walton, S.; Emanuel, R.W.; Swanton, R.H.; Campos Costa, D.; Laming, P.J.; Ell, P.J.

    1987-01-01

    Stress induced changes in left ventricular ejection fraction are widely used in the detection and assessment of coronary artery disease. This study demonstrates that right ventricular dysfunction may also occur, and assesses its significance in terms of coronary artery anatomy. This study involved 14 normal subjects and 26 with coronary artery disease investigated by equilibrium radionuclide ventriculography, at rest and during maximal dynamic exercise. Mean normal resting right ventricular ejection fraction (RVEF) was 0.40 (SD 0.118), and all normal subjects increased RVEF with stress (mean ΔRVEF+0.13 SD 0.099). Mean ΔRVEF in the subjects with coronary artery disease was significantly lower at 0.00 (SD 0.080), but there was overlap between the two groups. The largest falls in RVEF were seen if the right coronary artery was occluded without retrograde filling. In this subgroup with the most severely compromised right ventricular perfusion (nine subjects), RVEF always fell with stress, and mean ΔRVEF was -0.08 (SD 0.050). There was no significant correlation between ΔLVEF and ΔRVEF, implying that the right ventricular dysfunction was due to right ventricular ischaemia, rather than secondary to left ventricular dysfunction. Stress induced right ventricular ischaemia can therefore be detected readily by radionuclide ventriculography. (orig.)

  6. Action potential conduction between a ventricular cell model and an isolated ventricular cell

    NARCIS (Netherlands)

    Wilders, R.; Kumar, R.; Joyner, R. W.; Jongsma, H. J.; Verheijck, E. E.; Golod, D.; van Ginneken, A. C.; Goolsby, W. N.

    1996-01-01

    We used the Luo and Rudy (LR) mathematical model of the guinea pig ventricular cell coupled to experimentally recorded guinea pig ventricular cells to investigate the effects of geometrical asymmetry on action potential propagation. The overall correspondence of the LR cell model with the recorded

  7. Right ventricular failure after implantation of a continuous-flow left ventricular assist device

    DEFF Research Database (Denmark)

    Cordtz, Johan Joakim; Nilsson, Jens C; Hansen, Peter B

    2014-01-01

    Right ventricular failure (RVF) is a significant complication after implantation of a left ventricular assist device. We aimed to identify haemodynamic changes in the early postoperative phase that predicted subsequent development of RVF in a cohort of HeartMate II (HMII) implanted patients....

  8. Improving left ventricular segmentation in four-dimensional flow MRI using intramodality image registration for cardiac blood flow analysis.

    Science.gov (United States)

    Gupta, Vikas; Bustamante, Mariana; Fredriksson, Alexandru; Carlhäll, Carl-Johan; Ebbers, Tino

    2018-01-01

    Assessment of blood flow in the left ventricle using four-dimensional flow MRI requires accurate left ventricle segmentation that is often hampered by the low contrast between blood and the myocardium. The purpose of this work is to improve left-ventricular segmentation in four-dimensional flow MRI for reliable blood flow analysis. The left ventricle segmentations are first obtained using morphological cine-MRI with better in-plane resolution and contrast, and then aligned to four-dimensional flow MRI data. This alignment is, however, not trivial due to inter-slice misalignment errors caused by patient motion and respiratory drift during breath-hold based cine-MRI acquisition. A robust image registration based framework is proposed to mitigate such errors automatically. Data from 20 subjects, including healthy volunteers and patients, was used to evaluate its geometric accuracy and impact on blood flow analysis. High spatial correspondence was observed between manually and automatically aligned segmentations, and the improvements in alignment compared to uncorrected segmentations were significant (P  0.05). Our results demonstrate the efficacy of the proposed approach in improving left-ventricular segmentation in four-dimensional flow MRI, and its potential for reliable blood flow analysis. Magn Reson Med 79:554-560, 2018. © 2017 International Society for Magnetic Resonance in Medicine. © 2017 International Society for Magnetic Resonance in Medicine.

  9. High pulmonary vascular resistance in addition to low right ventricular stroke work index effectively predicts biventricular assist device requirement.

    Science.gov (United States)

    Imamura, Teruhiko; Kinugawa, Koichiro; Kinoshita, Osamu; Nawata, Kan; Ono, Minoru

    2016-03-01

    Although the right ventricular stroke work index (RVSWI) is a good index for RV function, a low RVSWI is not necessarily an indicator for the need for a right ventricular assist device at the time of left VAD implantation. We here aimed to determine a more precise indicator for the need for a biventricular assist device (BiVAD). In total, 116 patients (mean age, 38 ± 14 years), who underwent hemodynamic assessments preoperatively including 12 BiVAD patients, and had been followed at our institute from 2003 to 2015, were included. Multivariate logistic regression analysis indicated that RVSWI and pulmonary vascular resistance (PVR) were independent predictors of BiVAD requirement (P 5 g/m, PVR 5, PVR > 3.7), (3) RV failure (RVSWI 3.7), and examined. Most of the patients in Group 4 (75 %), with acutely depressed hemodynamics and inflammatory responses in the myocardium, required BiVAD. Overall, patients with BiVAD had a worse survival rate as compared with those with LVAD alone. In conclusion, high PVR in addition to low RVSWI effectively predicts BiVAD requirement.

  10. Exercise thallium testing in ventricular preexcitation

    Energy Technology Data Exchange (ETDEWEB)

    Archer, S.; Gornick, C.; Grund, F.; Shafer, R.; Weir, E.K.

    1987-05-01

    Ventricular preexcitation, as seen in Wolff-Parkinson-White syndrome, results in a high frequency of positive exercise electrocardiographic responses. Why this occurs is unknown but is not believed to reflect myocardial ischemia. Exercise thallium testing is often used for noninvasive assessment of coronary artery disease in patients with conditions known to result in false-positive electrocardiographic responses. To assess the effects of ventricular preexcitation on exercise thallium testing, 8 men (aged 42 +/- 4 years) with this finding were studied. No subject had signs or symptoms of coronary artery disease. Subjects exercised on a bicycle ergometer to a double product of 26,000 +/- 2,000 (+/- standard error of mean). All but one of the subjects had at least 1 mm of ST-segment depression. Tests were terminated because of fatigue or dyspnea and no patient had chest pain. Thallium test results were abnormal in 5 patients, 2 of whom had stress defects as well as abnormally delayed thallium washout. One of these subjects had normal coronary arteries on angiography with a negative ergonovine challenge, and both had normal exercise radionuclide ventriculographic studies. Delayed thallium washout was noted in 3 of the subjects with ventricular preexcitation and normal stress images. This study suggests that exercise thallium testing is frequently abnormal in subjects with ventricular preexcitation. Ventricular preexcitation may cause dyssynergy of ventricular activation, which could alter myocardial thallium handling, much as occurs with left bundle branch block. Exercise radionuclide ventriculography may be a better test for noninvasive assessment of coronary artery disease in patients with ventricular preexcitation.

  11. Exercise thallium testing in ventricular preexcitation

    International Nuclear Information System (INIS)

    Archer, S.; Gornick, C.; Grund, F.; Shafer, R.; Weir, E.K.

    1987-01-01

    Ventricular preexcitation, as seen in Wolff-Parkinson-White syndrome, results in a high frequency of positive exercise electrocardiographic responses. Why this occurs is unknown but is not believed to reflect myocardial ischemia. Exercise thallium testing is often used for noninvasive assessment of coronary artery disease in patients with conditions known to result in false-positive electrocardiographic responses. To assess the effects of ventricular preexcitation on exercise thallium testing, 8 men (aged 42 +/- 4 years) with this finding were studied. No subject had signs or symptoms of coronary artery disease. Subjects exercised on a bicycle ergometer to a double product of 26,000 +/- 2,000 (+/- standard error of mean). All but one of the subjects had at least 1 mm of ST-segment depression. Tests were terminated because of fatigue or dyspnea and no patient had chest pain. Thallium test results were abnormal in 5 patients, 2 of whom had stress defects as well as abnormally delayed thallium washout. One of these subjects had normal coronary arteries on angiography with a negative ergonovine challenge, and both had normal exercise radionuclide ventriculographic studies. Delayed thallium washout was noted in 3 of the subjects with ventricular preexcitation and normal stress images. This study suggests that exercise thallium testing is frequently abnormal in subjects with ventricular preexcitation. Ventricular preexcitation may cause dyssynergy of ventricular activation, which could alter myocardial thallium handling, much as occurs with left bundle branch block. Exercise radionuclide ventriculography may be a better test for noninvasive assessment of coronary artery disease in patients with ventricular preexcitation

  12. Hyperglycemia can delay left ventricular dysfunction but not autonomic damage after myocardial infarction in rodents

    Directory of Open Access Journals (Sweden)

    Brum Patricia C

    2011-04-01

    Full Text Available Abstract Background Although clinical diabetes mellitus is obviously a high risk factor for myocardial infarction (MI, in experimental studies disagreement exists about the sensitivity to ischemic injury of an infarcted myocardium. Recently, our group demonstrated that diabetic animals presented better cardiac function recovery and cellular resistance to ischemic injury than nondiabetics. In the present study, we evaluated the chronic effects of MI on left ventricular (LV and autonomic functions in streptozotocin (STZ diabetic rats. Methods Male Wistar rats were divided into 4 groups: control (C, n = 15, diabetes (D, n = 16, MI (I, n = 21, and diabetes + MI (DI, n = 30. MI was induced 15 days after diabetes (STZ induction. Ninety days after MI, LV and autonomic functions were evaluated (8 animals each group. Left ventricular homogenates were analyzed by Western blotting to evaluate the expression of calcium handling proteins. Results MI area was similar in infarcted groups (~43%. Ejection fraction and +dP/dt were reduced in I compared with DI. End-diastolic pressure was additionally increased in I compared with DI. Compared with DI, I had increased Na+-Ca2+ exchange and phospholamban expression (164% and decreased phosphorylated phospholamban at serine16 (65% and threonine17 (70% expression. Nevertheless, diabetic groups had greater autonomic dysfunction, observed by baroreflex sensitivity and pulse interval variability reductions. Consequently, the mortality rate was increased in DI compared with I, D, and C groups. Conclusions LV dysfunction in diabetic animals was attenuated after 90 days of myocardial infarction and was associated with a better profile of calcium handling proteins. However, this positive adaptation was not able to reduce the mortality rate of DI animals, suggesting that autonomic dysfunction is associated with increased mortality in this group. Therefore, it is possible that the better cardiac function has been transitory

  13. Image processing of x-ray left ventricular cineangiocardiograms and displays of cardiac functions

    International Nuclear Information System (INIS)

    Eiho, Shigeru; Yamada, Shigeru; Kuwahara, Michiyoshi

    1980-01-01

    Cineangiocardiography has been often used as one of the highly helpful techniques to examine the cardiac function. This paper deals with the method of tracing automatically the boundaries of the left ventricle on cineangiocardiograms, the method to evaluate and display various cardiac functions, the method to reconstruct the left ventricular cavity from biplane cineangiocardiograms and the method to display a 3-dimensional shape of the left ventricle reconstructed. Our algorithm of boundary tracing is based on a heuristic search for a local maximum of the changing rate in the gray level of cineangiocardiogram. The boundaries of endocardial margins of the left ventricle on 80 to 120 consecutive frames are automatically traced by our method. By using the detected boundaries of the left ventricle, a lot of quantitative information may be established on the cardiac function. The volume change, the wall motions and the %-shortening are displayed graphically. The motion of the boundary of the left ventricle is displayed on a CRT as a moving picture. The left ventricular cavity is reconstructed from the detected boundaries of the left ventricle on biplane cineangiocardiograms. A reconstructed image can be shown as superimposed lines or halftone planes to produce a 3-dimensional perspective. The %-shortening which shows the contractility of the regional myocardium is displayed on a silhouette of the left ventricle. We can easily recognize the abnormal area of contraction and the level and spread of abnormality from this displayed image. With the use of the system described in this paper, we can grasp the movement of the left ventricle exactly and evaluate the cardiac function quantitatively. (author)

  14. Hypercholesterolemic myocardium is vulnerable to ischemia-reperfusion injury and refractory to sevoflurane-induced protection.

    Directory of Open Access Journals (Sweden)

    Yong Xu

    Full Text Available Recent studies have demonstrated that volatile anesthetic postconditioning confers myocardial protection against ischemia-reperfusion (IR injury through activation of the reperfusion injury salvage kinase (RISK pathway. As RISK has been shown to be impaired in hypercholesterolemia. Therefore, we investigate whether anesthetic-induced cardiac protection was maintained in hypercholesterolemic rats. In the present study, normocholesteolemic or hypercholesterolemic rat hearts were subjected to 30 min of ischemia and 2 h of reperfusion. Animals received 2.4% sevoflurane for 5 min or 3 cycles of 10-s ischemia/10-s reperfusion. The hemodynamic parameters, including left ventricular developed pressure, left ventricular end-diastolic pressure and heart rate, were continuously monitored. The infarct size, apoptosis, p-Akt, p-ERK1/2, p-GSK3β were determined. We found that both sevoflurane and ischemic postconditioning significantly improved heart pump function, reduced infarct size and increased the phosphorylation of Akt, ERK1/2 and their downstream target of GSK3β in the healthy rats. In the hypercholesterolemic rats, neither sevoflurane nor ischemic postconditioning improved left ventricular hemodynamics, reduced infarct size and increased the phosphorylated Akt, ERK1/2 and GSK3β. In contrast, GSK inhibitor SB216763 conferred cardioprotection against IR injury in healthy and hypercholesterolemic hearts. In conclusions, hyperchoesterolemia abrogated sevoflurane-induced cardioprotection against IR injury by alteration of upstream signaling of GSK3β and acute GSK inhibition may provide a novel therapeutic strategy to protect hypercholesterolemic hearts against IR injury.

  15. Dynamic Changes of QRS Morphology of Premature Ventricular Contractions During Ablation in the Right Ventricular Outflow Tract: A Case Report.

    Science.gov (United States)

    Yue-Chun, Li; Jia-Feng, Lin; Jia-Xuan, Lin

    2015-10-01

    Electrocardiographic characteristics can be useful in differentiating between right ventricular outflow tract (RVOT) and aortic sinus cusp (ASC) ventricular arrhythmias. Ventricular arrhythmias originating from ASC, however, show preferential conduction to RVOT that may render the algorithms of electrocardiographic characteristics less reliable. Even though there are few reports describing ventricular arrhythmias with ASC origins and endocardial breakout sites of RVOT, progressive dynamic changes in QRS morphology of the ventricular arrhythmias during ablation obtained were rare.This case report describes a patient with symptomatic premature ventricular contractions of left ASC origin presenting an electrocardiogram (ECG) characteristic of right ventricular outflow tract before ablation. Pacing at right ventricular outflow tract reproduced an excellent pace map. When radiofrequency catheter ablation was applied to the right ventricular outflow tract, the QRS morphology of premature ventricular contractions progressively changed from ECG characteristics of right ventricular outflow tract origin to ECG characteristics of left ASC origin.Successful radiofrequency catheter ablation was achieved at the site of the earliest ventricular activation in the left ASC. The distance between the successful ablation site of the left ASC and the site with an excellent pace map of the RVOT was 20 mm.The ndings could be strong evidence for a preferential conduction via the myocardial bers from the ASC origin to the breakout site in the right ventricular outflow tract. This case demonstrates that ventricular arrhythmias with a single origin and exit shift may exhibit QRS morphology changes.

  16. Muscular anatomy of the human ventricular folds.

    Science.gov (United States)

    Moon, Jerald; Alipour, Fariborz

    2013-09-01

    Our purpose in this study was to better understand the muscular anatomy of the ventricular folds in order to help improve biomechanical modeling of phonation and to better understand the role of these muscles during phonatory and nonphonatory tasks. Four human larynges were decalcified, sectioned coronally from posterior to anterior by a CryoJane tape transfer system, and stained with Masson's trichrome. The total and relative areas of muscles observed in each section were calculated and used for characterizing the muscle distribution within the ventricular folds. The ventricular folds contained anteriorly coursing thyroarytenoid and ventricularis muscle fibers that were in the lower half of the ventricular fold posteriorly, and some ventricularis muscle was evident in the upper and lateral portions of the fold more anteriorly. Very little muscle tissue was observed in the medial half of the fold, and the anterior half of the ventricular fold was largely devoid of any muscle tissue. All 4 larynges contained muscle bundles that coursed superiorly and medially through the upper half of the fold, toward the lateral margin of the epiglottis. Although variability of expression was evident, a well-defined thyroarytenoid muscle was readily apparent lateral to the arytenoid cartilage in all specimens.

  17. Study of rNIS as a reporter gene monitoring rBMSC transplanted to rat myocardium

    International Nuclear Information System (INIS)

    Hu Shou; Lan Xiaoli; Cao Wei; Cao Guoxiang; Zhang Guopeng; Zhang Binqing; Wu Tao; Chang Wei; Zhang Yongxue

    2010-01-01

    Objective: To investigate the feasibility of rat sodium/iodide symporter (rNIS) as a reporter gene monitoring rat bone marrow mesenchymal cells (rBMSC) transplanted to rat myocardium in vivo. Methods: Recombinated adenovirus vector was constructed by rNIS/enhanced green fluorescence protein (EGFP) (Ad-rNIS/EGFP). rBMSC transfected by Ad-rNIS/EGFP were studied using fluorescence microscope. Fifteen rats were transplanted with rBMSC and randomly divided into three groups: rNIS group (with rNIS transfection), blocked group (with rNIS transfection) by oral intake of perchloric sodium before planar imaging (GE Millennium MPR SPECT), and control group (without rNIS transfection). All rats underwent 99 Tc m -pertechnetate planar imaging. The biological distribution of 99 Tc m -pertechnetate was studied. The expressions of rNIS gene and protein in myocardium were measured by real time polymerase chain reaction (PCR) and western blot, respectively. The expressions of CD 29 , CD 44 , CD 90 , CD 11 b, CD 34 and CD 45 were measured by immunohistochemistry. Results: rBMSC transfected by Ad-rNIS/EGFP showed EGFP expression under fluorescence microscope. The transplanted rat myocardium could be visualized on 99 Tc m -pertechnetate planar imaging in rNIS group. The relative uptake ratio (R heart /R hmb , RUR) was 6.7 ±0.4. RUR in control group (3.0 ±0.2) was lower than that in rNIS group (t =2.78, P=0.03). The percentage injection dose per gram of tissue (% ID/g) of the transplanted myocardium was 60.2 ± 20.8 in rNIS group, which was higher than that (2.5 ± 0.4) % ID/g of control group ( t = 7.13, P 29 , CD 44 and CD 90 were positive, CD 45 and CD 45 negative CD 11 b mildly positive in the myocardium transplanted with infective rBMSC. Conclusion: rNIS can efficiently monitor rBMSC transplanted to rat myocardium. (authors)

  18. 123I-MIBG myocardial imaging in hypertensive patients. Abnormality progresses with left ventricular hypertrophy

    International Nuclear Information System (INIS)

    Mitani, Isao; Sumita, Shinichi; Takahashi, Nobukazu; Ochiai, Hisao; Ishii, Masao

    1996-01-01

    Twenty-seven patients with essential hypertension were prospectively studied with 123 I-labeled metaiodobenzyl-guanidine ( 123 I-MIBG) to assess the presence and location of impaired sympathetic innervation in hypertrophied myocardium. Thirteen patients had left ventricular hypertrophy on echocardiography, and 14 had normal echocardiograms. The wash-out ratio of 123 I-MIBG in these two groups did not differ significantly (35.3±6.1 and 35.4±5.1) but was higher than in control subjects (29.4±6.7). The delayed heart-to-mediastinum count ratio was lower in the patients with hypertrophy than in the patients without hypertrophy (1.93±0.28 and 2.22±0.21; p<0.05) and the control subjects (1.93±0.28 and 2.33±0.25; p<0.05). On SPECT imaging, abnormalities in segmental uptake were frequent at the posterior and postero-lateral wall in both groups, although the hypertrophic group had more significant impairment. Our results lead to the hypothesis that hypertension in more advanced stages may be associated not only with hypertrophic changes but also with more advanced regional impairment of cardiac sympathetic innervation. (author)

  19. Left ventricular strain and its pattern estimated from cine CMR and validation with DENSE

    International Nuclear Information System (INIS)

    Gao, Hao; Luo, Xiaoyu; Allan, Andrew; McComb, Christie; Berry, Colin

    2014-01-01

    Measurement of local strain provides insight into the biomechanical significance of viable myocardium. We attempted to estimate myocardial strain from cine cardiovascular magnetic resonance (CMR) images by using a b-spline deformable image registration method. Three healthy volunteers and 41 patients with either recent or chronic myocardial infarction (MI) were studied at 1.5 Tesla with both cine and DENSE CMR. Regional circumferential and radial left ventricular strains were estimated from cine and DENSE acquisitions. In all healthy volunteers, there was no difference for peak circumferential strain (− 0.18 ± 0.04 versus − 0.18 ± 0.03, p = 0.76) between cine and DENSE CMR, however peak radial strain was overestimated from cine (0.84 ± 0.37 versus 0.49 ± 0.2, p < 0.01). In the patient study, the peak strain patterns predicted by cine were similar to the patterns from DENSE, including the strain evolution related to recovery time and strain patterns related to MI scar extent. Furthermore, cine-derived strain disclosed different strain patterns in MI and non-MI regions, and regions with transmural and non-transmural MI as DENSE. Although there were large variations with radial strain measurements from cine CMR images, useful circumferential strain information can be obtained from routine clinical CMR imaging. Cine strain analysis has potential to improve the diagnostic yield from routine CMR imaging in clinical practice. (paper)

  20. Left ventricular strain and its pattern estimated from cine CMR and validation with DENSE.

    Science.gov (United States)

    Gao, Hao; Allan, Andrew; McComb, Christie; Luo, Xiaoyu; Berry, Colin

    2014-07-07

    Measurement of local strain provides insight into the biomechanical significance of viable myocardium. We attempted to estimate myocardial strain from cine cardiovascular magnetic resonance (CMR) images by using a b-spline deformable image registration method. Three healthy volunteers and 41 patients with either recent or chronic myocardial infarction (MI) were studied at 1.5 Tesla with both cine and DENSE CMR. Regional circumferential and radial left ventricular strains were estimated from cine and DENSE acquisitions. In all healthy volunteers, there was no difference for peak circumferential strain (- 0.18 ± 0.04 versus - 0.18 ± 0.03, p = 0.76) between cine and DENSE CMR, however peak radial strain was overestimated from cine (0.84 ± 0.37 versus 0.49 ± 0.2, p cine were similar to the patterns from DENSE, including the strain evolution related to recovery time and strain patterns related to MI scar extent. Furthermore, cine-derived strain disclosed different strain patterns in MI and non-MI regions, and regions with transmural and non-transmural MI as DENSE. Although there were large variations with radial strain measurements from cine CMR images, useful circumferential strain information can be obtained from routine clinical CMR imaging. Cine strain analysis has potential to improve the diagnostic yield from routine CMR imaging in clinical practice.

  1. Characterization of ventricular depolarization and repolarization changes in a porcine model of myocardial infarction.

    Science.gov (United States)

    Romero, Daniel; Ringborn, Michael; Demidova, Marina; Koul, Sasha; Laguna, Pablo; Platonov, Pyotr G; Pueyo, Esther

    2012-12-01

    In this study, several electrocardiogram (ECG)-derived indices corresponding to both ventricular depolarization and repolarization were evaluated during acute myocardial ischemia in an experimental model of myocardial infarction produced by 40 min coronary balloon inflation in 13 pigs. Significant changes were rapidly observed from minute 4 after the start of coronary occlusion, achieving their maximum values between 11 and 22 min for depolarization and between 9 and 12 min for repolarization indices, respectively. Subsequently, these maximum changes started to decrease during the latter part of the occlusion. Depolarization changes associated with the second half of the QRS complex showed a significant but inverse correlation with the myocardium at risk (MaR) estimated by scintigraphic images. The correlation between MaR and changes of the downward slope of the QRS complex, [Formula: see text], evaluated at the two more relevant peaks observed during the occlusion, was r = -0.75, p evolution, respectively. Repolarization changes, analyzed by evaluation of ST segment elevation at the main observed positive peak, also showed negative, however non-significant correlation with MaR: r = -0.34, p = 0.28. Our results suggest that changes evaluated in the latter part of the depolarization, such as those described by [Formula: see text], which are influenced by R-wave amplitude, QRS width and ST level variations simultaneously, correlate better with the amount of ischemia than other indices evaluated in the earlier part of depolarization or during the ST segment.

  2. Left ventricular hypertrophy: virtuous intentions, malign consequences.

    Science.gov (United States)

    Pokharel, Saraswati; Sharma, Umesh C; Pinto, Yigal M

    2003-06-01

    Left ventricular hypertrophy (LVH) is currently the focus of intense cardiovascular research, with the resultant rapid evolution of novel concepts relating to its exceedingly complex pathophysiology. In addition to the alterations in signal transduction and disturbances in Ca(2+) homeostasis, there are structural changes in myofilaments, disorganization of the cytoskeletal framework and increased collagen synthesis. LVH is associated with progressive left ventricular remodeling that culminates to heart failure. The modern treatment of left ventricular hypertrophy is now largely based on the hypothesis that neuroendocrine activation is important in the progression of the disease and inhibition of neurohormones is likely to have long-term benefit with regard to morbidity and mortality. Drugs specifically designed to unload the left ventricle, such as diuretics and vasodilators, appears to be less effective in reducing LV mass and improving prognosis. Thus, the evolution of treatment for LVH itself has provided much enlightenment for our understanding of the fundamental biology of the disorder.

  3. Cytoskeletal role in the transition from compensated to decompensated hypertrophy during adult canine left ventricular pressure overloading

    Science.gov (United States)

    Tagawa, H.; Koide, M.; Sato, H.; Zile, M. R.; Carabello, B. A.; Cooper, G. 4th

    1998-01-01

    Increased microtubule density causes cardiocyte contractile dysfunction in right ventricular (RV) pressure-overload hypertrophy, and these linked phenotypic and contractile abnormalities persist and progress during the transition to failure. Although more severe in cells from failing than hypertrophied RVs, the mechanical defects are normalized in each case by microtubule depolymerization. To define the role of increased microtubule density in left ventricular (LV) pressure-overload hypertrophy and failure, in a given LV we examined ventricular mechanics, sarcomere mechanics, and free tubulin and microtubule levels in control dogs and in dogs with aortic stenosis both with LV hypertrophy alone and with initially compensated hypertrophy that had progressed to LV muscle failure. In comparing initial values with those at study 8 weeks later, dogs with hypertrophy alone had a very substantial increase in LV mass but preservation of a normal ejection fraction and mean systolic wall stress. Dogs with hypertrophy and associated failure had a substantial but lesser increase in LV mass and a reduction in ejection fraction, as well as a marked increase in mean systolic wall stress. Cardiocyte contractile function was equivalent, and unaffected by microtubule depolymerization, in cells from control LVs and those with compensated hypertrophy. In contrast, cardiocyte contractile function in cells from failing LVs was quite depressed but was normalized by microtubule depolymerization. Microtubules were increased only in failing LVs. These contractile and cytoskeletal changes, when assayed longitudinally in a given dog by biopsy, appeared in failing ventricles only when wall stress began to increase and function began to decrease. Thus, the microtubule-based cardiocyte contractile dysfunction characteristic of pressure-hypertrophied myocardium, originally described in the RV, obtains equally in the LV but is shown here to have a specific association with increased wall stress.

  4. Mammalian Sperm Motility: Observation and Theory

    KAUST Repository

    Gaffney, E.A.

    2011-01-21

    Mammalian spermatozoa motility is a subject of growing importance because of rising human infertility and the possibility of improving animal breeding. We highlight opportunities for fluid and continuum dynamics to provide novel insights concerning the mechanics of these specialized cells, especially during their remarkable journey to the egg. The biological structure of the motile sperm appendage, the flagellum, is described and placed in the context of the mechanics underlying the migration of mammalian sperm through the numerous environments of the female reproductive tract. This process demands certain specific changes to flagellar movement and motility for which further mechanical insight would be valuable, although this requires improved modeling capabilities, particularly to increase our understanding of sperm progression in vivo. We summarize current theoretical studies, highlighting the synergistic combination of imaging and theory in exploring sperm motility, and discuss the challenges for future observational and theoretical studies in understanding the underlying mechanics. © 2011 by Annual Reviews. All rights reserved.

  5. Radiation effects in mammalian cells in vitro

    International Nuclear Information System (INIS)

    Hill, C.K.; Han, A.; Elkind, M.M.; Wells, R.L.; Buess, E.M.; Lin, C.M.

    1985-01-01

    The purpose of this research effort is to elucidate the mechanisms for the radiation-induced changes in mammalian cells that lead to cell death, mutation, neoplastic transformation, DNA damage, and chromosomal alterations. Of particular interest are the effects of low-dose-rate and fractionated irradiation on these end points with respect to the mechanisms whereby these effects are influenced by cellular repair processes, inhibitors, and promoters that act at the genetic or biochemical level. 17 refs

  6. Cellular and Chemical Neuroscience of Mammalian Sleep

    OpenAIRE

    Datta, Subimal

    2010-01-01

    Extraordinary strides have been made toward understanding the complexities and regulatory mechanisms of sleep over the past two decades, thanks to the help of rapidly evolving technologies. At its most basic level, mammalian sleep is a restorative process of the brain and body. Beyond its primary restorative purpose, sleep is essential for a number of vital functions. Our primary research interest is to understand the cellular and molecular mechanisms underlying the regulation of sleep and it...

  7. Relationship between Fibrosis and Ventricular Arrhythmias in Chagas Heart Disease Without Ventricular Dysfunction

    Energy Technology Data Exchange (ETDEWEB)

    Tassi, Eduardo Marinho, E-mail: etassi@ibest.com.br [Instituto de Cardiologia Edson Saad - Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil); Continentino, Marcelo Abramoff [Hospital Frei Galvão, Guaratinguetá, SP (Brazil); Nascimento, Emília Matos do; Pereira, Basílio de Bragança [Instituto de Cardiologia Edson Saad - Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil); Coppe - Instituto Alberto Luiz Coimbra de Pós-Graduação e Pesquisa de Engenharia - UFRJ, Rio de Janeiro, RJ (Brazil); Pedrosa, Roberto Coury [Instituto de Cardiologia Edson Saad - Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil)

    2014-05-15

    Patients with Chagas disease and segmental wall motion abnormality (SWMA) have worse prognosis independent of left ventricular ejection fraction (LVEF). Cardiac magnetic resonance (CMR) is currently the best method to detect SWMA and to assess fibrosis. To quantify fibrosis by using late gadolinium enhancement CMR in patients with Chagas disease and preserved or minimally impaired ventricular function (> 45%), and to detect patterns of dependence between fibrosis, SWMA and LVEF in the presence of ventricular arrhythmia. Electrocardiogram, treadmill exercise test, Holter and CMR were carried out in 61 patients, who were divided into three groups as follows: (1) normal electrocardiogram and CMR without SWMA; (2) abnormal electrocardiogram and CMR without SWMA; (3) CMR with SWMA independently of electrocardiogram. The number of patients with ventricular arrhythmia in relation to the total of patients, the percentage of fibrosis, and the LVEF were, respectively: Group 1, 4/26, 0.74% and 74.34%; Group 2, 4/16, 3.96% and 68.5%; and Group 3, 11/19, 14.07% and 55.59%. Ventricular arrhythmia was found in 31.1% of the patients. Those with and without ventricular arrhythmia had mean LVEF of 59.87% and 70.18%, respectively, and fibrosis percentage of 11.03% and 3.01%, respectively. Of the variables SWMA, groups, age, LVEF and fibrosis, only the latter was significant for the presence of ventricular arrhythmia, with a cutoff point of 11.78% for fibrosis mass (p < 0.001). Even in patients with Chagas disease and preserved or minimally impaired ventricular function, electrical instability can be present. Regarding the presence of ventricular arrhythmia, fibrosis is the most important variable, its amount being proportional to the complexity of the groups.

  8. Relationship between Fibrosis and Ventricular Arrhythmias in Chagas Heart Disease Without Ventricular Dysfunction

    International Nuclear Information System (INIS)

    Tassi, Eduardo Marinho; Continentino, Marcelo Abramoff; Nascimento, Emília Matos do; Pereira, Basílio de Bragança; Pedrosa, Roberto Coury

    2014-01-01

    Patients with Chagas disease and segmental wall motion abnormality (SWMA) have worse prognosis independent of left ventricular ejection fraction (LVEF). Cardiac magnetic resonance (CMR) is currently the best method to detect SWMA and to assess fibrosis. To quantify fibrosis by using late gadolinium enhancement CMR in patients with Chagas disease and preserved or minimally impaired ventricular function (> 45%), and to detect patterns of dependence between fibrosis, SWMA and LVEF in the presence of ventricular arrhythmia. Electrocardiogram, treadmill exercise test, Holter and CMR were carried out in 61 patients, who were divided into three groups as follows: (1) normal electrocardiogram and CMR without SWMA; (2) abnormal electrocardiogram and CMR without SWMA; (3) CMR with SWMA independently of electrocardiogram. The number of patients with ventricular arrhythmia in relation to the total of patients, the percentage of fibrosis, and the LVEF were, respectively: Group 1, 4/26, 0.74% and 74.34%; Group 2, 4/16, 3.96% and 68.5%; and Group 3, 11/19, 14.07% and 55.59%. Ventricular arrhythmia was found in 31.1% of the patients. Those with and without ventricular arrhythmia had mean LVEF of 59.87% and 70.18%, respectively, and fibrosis percentage of 11.03% and 3.01%, respectively. Of the variables SWMA, groups, age, LVEF and fibrosis, only the latter was significant for the presence of ventricular arrhythmia, with a cutoff point of 11.78% for fibrosis mass (p < 0.001). Even in patients with Chagas disease and preserved or minimally impaired ventricular function, electrical instability can be present. Regarding the presence of ventricular arrhythmia, fibrosis is the most important variable, its amount being proportional to the complexity of the groups

  9. Mammalian Synthetic Biology: Engineering Biological Systems.

    Science.gov (United States)

    Black, Joshua B; Perez-Pinera, Pablo; Gersbach, Charles A

    2017-06-21

    The programming of new functions into mammalian cells has tremendous application in research and medicine. Continued improvements in the capacity to sequence and synthesize DNA have rapidly increased our understanding of mechanisms of gene function and regulation on a genome-wide scale and have expanded the set of genetic components available for programming cell biology. The invention of new research tools, including targetable DNA-binding systems such as CRISPR/Cas9 and sensor-actuator devices that can recognize and respond to diverse chemical, mechanical, and optical inputs, has enabled precise control of complex cellular behaviors at unprecedented spatial and temporal resolution. These tools have been critical for the expansion of synthetic biology techniques from prokaryotic and lower eukaryotic hosts to mammalian systems. Recent progress in the development of genome and epigenome editing tools and in the engineering of designer cells with programmable genetic circuits is expanding approaches to prevent, diagnose, and treat disease and to establish personalized theranostic strategies for next-generation medicines. This review summarizes the development of these enabling technologies and their application to transforming mammalian synthetic biology into a distinct field in research and medicine.

  10. Comparison of amphibian and mammalian thyroperoxidase ...

    Science.gov (United States)

    Thyroperoxidase (TPO) catalyzes the production of thyroid hormones in the vertebrate thyroid gland by oxidizing iodide (I- ) to produce iodinated tyrosines on thyroglobulin, and further coupling of specific mono- or di-iodinated tyrosines to generate the triiodo- and tetra-iodothyronine, precursors to thyroid hormone. This enzyme is a target for thyroid disrupting chemicals. TPO-inhibition by xenobiotics is a molecular initiating event that is known to perturb the thyroid axis by preventing synthesis of thyroid hormone. Previous work on TPO-inhibition has been focused on mammalian TPO; specifically, the rat and pig. A primary objective of this experiment was to directly measure TPO activity in a non-mammalian system, in this case a thyroid gland homogenate from Xenopus laevis; as well as compare chemical inhibition from past mammalian studies to the amphibian data generated. Thyroid glands obtained from X. laevis tadpoles at NF stages 58-60, were pooled and homogenized by sonication in phosphate buffer. This homogenate was then used to test 24 chemicals for inhibition of TPO as measured by conversion of Amplex UltraRed (AUR) substrate to its fluorescent product. The test chemicals were selected based upon previous results from rat in vitro TPO assays, and X. laevis in vitro and in vivo studies for thyroid disrupting endpoints, and included both positive and negative chemicals in these assays. An initial screening of the chemicals was done at a single high con

  11. Left cardiac sympathetic denervation for catecholaminergic polymorphic ventricular tachycardia

    NARCIS (Netherlands)

    Wilde, Arthur A. M.; Bhuiyan, Zahurul A.; Crotti, Lia; Facchini, Mario; de Ferrari, Gaetano M.; Paul, Thomas; Ferrandi, Chiara; Koolbergen, Dave R.; Odero, Attilio; Schwartz, Peter J.

    2008-01-01

    Catecholaminergic polymorphic ventricular tachycardia is a potentially lethal disease characterized by adrenergically mediated ventricular arrhythmias manifested especially in children and teenagers. Beta-blockers are the cornerstone of therapy, but some patients do not have a complete response to

  12. Evaluation of right ventricular volumes measured by magnetic resonance imaging

    DEFF Research Database (Denmark)

    Møgelvang, J; Stubgaard, M; Thomsen, C

    1988-01-01

    stroke volume was calculated as the difference between end-diastolic and end-systolic volume and compared to left ventricular stroke volume and to stroke volume determined simultaneously by a classical indicator dilution technique. There was good agreement between right ventricular stroke volume......Right ventricular volumes were determined in 12 patients with different levels of right and left ventricular function by magnetic resonance imaging (MRI) using an ECG gated multisection technique in planes perpendicular to the diastolic position of the interventricular septum. Right ventricular...... determined by MRI and by the indicator dilution method and between right and left ventricular stroke volume determined by MRI. Thus, MRI gives reliable values not only for left ventricular volumes, but also for right ventricular volumes. By MRI it is possible to obtain volumes from both ventricles...

  13. An Incidentally Detected Right Ventricular Pseudoaneurysm

    Directory of Open Access Journals (Sweden)

    Vamsi C. Gaddipati

    2017-01-01

    Full Text Available Ventricular pseudoaneurysm is an uncommon, potentially fatal complication that has been associated with myocardial infarction, cardiac surgery, chest trauma, and infectious processes. Diagnosis can be challenging, as cases are rare and slowly progressing and typically lack identifiable features on clinical presentation. As a result, advanced imaging techniques have become the hallmark of identification. Ahead, we describe a patient who presents with acute decompensated heart failure and was incidentally discovered to have a large right ventricular pseudoaneurysm that developed following previous traumatic anterior rib fracture.

  14. Left ventricular performance during psychological stress

    International Nuclear Information System (INIS)

    Young, D.Z.; Massachusetts General Hospital, Boston; Dimsdale, J.E.; Moore, R.H.; Barlai-Kovach, M.; Newell, J.B.; McKusick, K.A.; Boucher, C.A.; Fifer, M.A.; Strauss, H.W.

    1989-01-01

    Left ventricular ejection fraction, systolic blood pressure and plasma norepinephrine were measured in six normotensive and six mildly hypertensive subjects during rest and psychological stress. Compared with rest, 8 of the 12 subjects developed significant changes in ejection fraction (increase in 6, decrease in 2); 10 of 12 subjects developed significant elevations of plasma norepinephrine; and all developed significant increases in systolic blood pressure. When the stress effects were examined for the total group, as opposed to within subjects, there were significant increases in plasma norepinephrine and systolic blood pressure but, interestingly, mean ejection fraction and stroke volume remained unchanged, implying stress led to increased left ventricular contractility. (orig.)

  15. Nuclear medical diagnostic with ventricular aneurysm

    International Nuclear Information System (INIS)

    Litter, H.

    1987-01-01

    In the diagnostic of ventricular aneurysms myocardial scintigraphy and above all radionuclide ventriculography (RNV) have special importance. Because of the non-invasive method and the as a result safe and easy use even with stress studies, RNV can provide a very valuable aid with aneurysm patients in early diagnosis, evaluation of the operability and as well as in the prognosis. It must be noted, however, that the differentiation of multivascular diseases and sometimes ventricular aneurysms can be difficult and the inclusion of an angiocardiograph as a radiological invasive examination procedure seems fitting. (orig./MG) [de

  16. Bidirectional ventricular tachycardia of unknown etiology

    International Nuclear Information System (INIS)

    Ali, M.; Khan, J.A.; Masood, T.; Shamsi, F.; Dero, M.H.; Khan, S.

    2013-01-01

    A 45 years old male presented to the emergency department with palpitations, headache and apprehension. His electrocardiogram revealed bidirectional ventricular tachycardia. He remained vitally stable and responded to intravenous beta-blocker. Initially digitalis toxicity was suspected but history was negative for digitalis intake. The cause remained unidentified in patient despite detailed investigations. During a short follow-up (of 6 months) he remained asymptomatic and no cause was further identified during this period. Some other unseen causes of bidirectional ventricular tachycardia need to be explored. (author)

  17. Catecholaminergic polymorphic ventricular tachycardia in 2012

    Directory of Open Access Journals (Sweden)

    Christian van der Werf

    2011-12-01

    Full Text Available Catecholaminergic polymorphic ventricular tachycardia (CPVT is a rare, potentially lethal inherited arrhythmia syndrome characterized by stress or emotion-induced ventricular arrhythmias. CPVT was first described in 1960, while the genetic basis underlying this syndrome was discovered in 2001. The past decade has seen substantial advances in understanding the pathophysiology of CPVT. In addition, significant advances have been made in elucidating clinical characteristics of CPVT patients and new treatment options have become available. Here, we review current literature on CPVT to present state-of-the-art knowledge on the subject of the genetic basis, pathophysiology, clinical presentation, diagnosis, treatment and prognosis.

  18. Isolated left ventricular non-compaction cardiomyopathy associated with polymorphous ventricular tachycardia mimicking torsades de pointes

    Directory of Open Access Journals (Sweden)

    Oana Dickinson

    2013-02-01

    Full Text Available Left ventricular non-compaction (LVNC cardiomyopathy is a rare congenital disorder, classified by the American Heart Association as a primary genetic cardiomyopathy and characterized by multiple trabeculations within the left ventricle. LVNC cardiomyopathy has been associated with 3 major clinical manifestations: heart failure, atrial and ventricular arrhythmias and thromboembolic events, including stroke. In this case report, we describe a female patient with apparently isolated LVNC in whom pause-dependent polymorphic ventricular tachycardia suggesting torsades de pointes occurred in the presence of a normal QT interval.

  19. YAP/TAZ enhance mammalian embryonic neural stem cell characteristics in a Tead-dependent manner

    Energy Technology Data Exchange (ETDEWEB)

    Han, Dasol; Byun, Sung-Hyun; Park, Soojeong; Kim, Juwan; Kim, Inhee; Ha, Soobong; Kwon, Mookwang; Yoon, Keejung, E-mail: keejung@skku.edu

    2015-02-27

    Mammalian brain development is regulated by multiple signaling pathways controlling cell proliferation, migration and differentiation. Here we show that YAP/TAZ enhance embryonic neural stem cell characteristics in a cell autonomous fashion using diverse experimental approaches. Introduction of retroviral vectors expressing YAP or TAZ into the mouse embryonic brain induced cell localization in the ventricular zone (VZ), which is the embryonic neural stem cell niche. This change in cell distribution in the cortical layer is due to the increased stemness of infected cells; YAP-expressing cells were colabeled with Sox2, a neural stem cell marker, and YAP/TAZ increased the frequency and size of neurospheres, indicating enhanced self-renewal- and proliferative ability of neural stem cells. These effects appear to be TEA domain family transcription factor (Tead)–dependent; a Tead binding-defective YAP mutant lost the ability to promote neural stem cell characteristics. Consistently, in utero gene transfer of a constitutively active form of Tead2 (Tead2-VP16) recapitulated all the features of YAP/TAZ overexpression, and dominant negative Tead2-EnR resulted in marked cell exit from the VZ toward outer cortical layers. Taken together, these results indicate that the Tead-dependent YAP/TAZ signaling pathway plays important roles in neural stem cell maintenance by enhancing stemness of neural stem cells during mammalian brain development. - Highlights: • Roles of YAP and Tead in vivo during mammalian brain development are clarified. • Expression of YAP promotes embryonic neural stem cell characteristics in vivo in a cell autonomous fashion. • Enhancement of neural stem cell characteristics by YAP depends on Tead. • Transcriptionally active form of Tead alone can recapitulate the effects of YAP. • Transcriptionally repressive form of Tead severely reduces stem cell characteristics.

  20. YAP/TAZ enhance mammalian embryonic neural stem cell characteristics in a Tead-dependent manner

    International Nuclear Information System (INIS)

    Han, Dasol; Byun, Sung-Hyun; Park, Soojeong; Kim, Juwan; Kim, Inhee; Ha, Soobong; Kwon, Mookwang; Yoon, Keejung

    2015-01-01

    Mammalian brain development is regulated by multiple signaling pathways controlling cell proliferation, migration and differentiation. Here we show that YAP/TAZ enhance embryonic neural stem cell characteristics in a cell autonomous fashion using diverse experimental approaches. Introduction of retroviral vectors expressing YAP or TAZ into the mouse embryonic brain induced cell localization in the ventricular zone (VZ), which is the embryonic neural stem cell niche. This change in cell distribution in the cortical layer is due to the increased stemness of infected cells; YAP-expressing cells were colabeled with Sox2, a neural stem cell marker, and YAP/TAZ increased the frequency and size of neurospheres, indicating enhanced self-renewal- and proliferative ability of neural stem cells. These effects appear to be TEA domain family transcription factor (Tead)–dependent; a Tead binding-defective YAP mutant lost the ability to promote neural stem cell characteristics. Consistently, in utero gene transfer of a constitutively active form of Tead2 (Tead2-VP16) recapitulated all the features of YAP/TAZ overexpression, and dominant negative Tead2-EnR resulted in marked cell exit from the VZ toward outer cortical layers. Taken together, these results indicate that the Tead-dependent YAP/TAZ signaling pathway plays important roles in neural stem cell maintenance by enhancing stemness of neural stem cells during mammalian brain development. - Highlights: • Roles of YAP and Tead in vivo during mammalian brain development are clarified. • Expression of YAP promotes embryonic neural stem cell characteristics in vivo in a cell autonomous fashion. • Enhancement of neural stem cell characteristics by YAP depends on Tead. • Transcriptionally active form of Tead alone can recapitulate the effects of YAP. • Transcriptionally repressive form of Tead severely reduces stem cell characteristics

  1. Infarct-remodeled myocardium is receptive to protection by isoflurane postconditioning: role of protein kinase B/Akt signaling.

    Science.gov (United States)

    Feng, Jianhua; Fischer, Gregor; Lucchinetti, Eliana; Zhu, Min; Bestmann, Lukas; Jegger, David; Arras, Margarete; Pasch, Thomas; Perriard, Jean-Claude; Schaub, Marcus C; Zaugg, Michael

    2006-05-01

    Postinfarct remodeled myocardium exhibits numerous structural and biochemical alterations. So far, it is unknown whether postconditioning elicited by volatile anesthetics can also provide protection in the remodeled myocardium. Myocardial infarct was induced in male Wistar rats by ligation of the left anterior descending coronary artery. Six weeks later, hearts were buffer-perfused and exposed to 40 min of ischemia followed by 90 min of reperfusion. Anesthetic postconditioning was induced by 15 min of 2.1 vol% isoflurane. In some experiments, LY294002 (15 microM), a phosphatidylinositol 3-kinase inhibitor, was coadministered with isoflurane. Masson's trichrome staining, immunohistochemistry, Western blot analysis, and reverse-transcription polymerase chain reaction served to confirm remodeling. In buffer-perfused hearts, functional recovery was recorded, and acute infarct size was measured using 1% triphenyltetrazolium chloride staining and lactate dehydrogenase release during reperfusion. Western blot analysis was used to determine phosphorylation of reperfusion injury salvage kinases including protein kinase B/Akt and its downstream targets after 15 min of reperfusion. Infarct hearts exhibited typical macroscopic and molecular changes of remodeling. Isoflurane postconditioning improved functional recovery and decreased acute infarct size, as determined by triphenyltetrazolium (35 +/- 5% in unprotected hearts vs. 8 +/- 3% in anesthetic postconditioning; P protection was abolished by LY294002, which inhibited phosphorylation of protein kinase B/Akt and its downstream targets glycogen synthase kinase 3beta, endothelial nitric oxide synthase, and p70S6 kinase. Infarct-remodeled myocardium is receptive to protection by isoflurane postconditioning via protein kinase B/Akt signaling. This is the first time to demonstrate that anesthetic postconditioning retains its marked protection in diseased myocardium.

  2. Structural alterations in rat myocardium induced by chronic l-arginine and l-NAME supplementation

    Directory of Open Access Journals (Sweden)

    Amal Abdussalam Ali A. Hmaid

    2018-03-01

    Full Text Available Structural changes affecting cardiomyocyte function may contribute to the pathophysiological remodeling underlying cardiac function impairment. Recent reports have shown that endogenous nitric oxide (NO plays an important role in this process. In order to examine the role of NO in cardiomyocyte remodeling, male rats were acclimated to room temperature (22 ± 1 °C or cold (4 ± 1 °C and treated with 2.25% l-arginine·HCl or 0.01% l-NAME (Nω-nitro-l-arginine methyl ester·HCl for 45 days. Untreated groups served as controls. Right heart ventricles were routinely prepared for light microscopic examination. Stereological estimations of volume densities of cardiomyocytes, surrounding blood vessels and connective tissue, as well as the morphometric measurements of cardiomyocyte diameters were performed. Tissue sections were also analyzed for structural alterations. We observed that both l-arginine and l-NAME supplementation induced cardiomyocyte hypertrophy, regardless of ambient temperature. However, cardiomyocyte hypertrophy was associated with fibrosis and extra collagen deposition only in the l-NAME treated group. Taken together, our results suggest that NO has a modulatory role in right heart ventricle remodeling by coordinating hypertrophy of cardiomyocytes and fibrous tissue preventing cardiac fibrosis. Keywords: Cardiomyocyte, Cardiac hypertrophy, l-Arginine, l-NAME, Myocardium

  3. Association of Atrial Fibrillation with Morphological and Electrophysiological Changes of the Atrial Myocardium.

    Science.gov (United States)

    Matějková, Adéla; Šteiner, Ivo

    Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia. For long time it was considered as pure functional disorder, but in recent years, there were identified atrial locations, which are involved in the initiation and maintenance of this arrhythmia. These structural changes, so called remodelation, start at electric level and later they affect contractility and morphology. In this study we attempted to find a possible relation between morphological (scarring, amyloidosis, left atrial (LA) enlargement) and electrophysiological (ECG features) changes in patients with AF. We examined grossly and histologically 100 hearts of necropsy patients - 54 with a history of AF and 46 without AF. Premortem ECGs were evaluated. The patients with AF had significantly heavier heart, larger LA, more severely scarred myocardium of the LA and atrial septum, and more severe amyloidosis in both atria. Severity of amyloidosis was higher in LAs vs. right atria (RAs). Distribution of both fibrosis and amyloidosis was irregular. The most affected area was in the LA anterior wall. Patients with a history of AF and with most severe amyloidosis have more often abnormally long P waves. Finding of long P wave may contribute to diagnosis of a hitherto undisclosed atrial fibrillation.

  4. Fiber architecture in remodeled myocardium revealed with a quantitative diffusion CMR tractography framework and histological validation.

    Science.gov (United States)

    Mekkaoui, Choukri; Huang, Shuning; Chen, Howard H; Dai, Guangping; Reese, Timothy G; Kostis, William J; Thiagalingam, Aravinda; Maurovich-Horvat, Pal; Ruskin, Jeremy N; Hoffmann, Udo; Jackowski, Marcel P; Sosnovik, David E

    2012-10-12

    The study of myofiber reorganization in the remote zone after myocardial infarction has been performed in 2D. Microstructural reorganization in remodeled hearts, however, can only be fully appreciated by considering myofibers as continuous 3D entities. The aim of this study was therefore to develop a technique for quantitative 3D diffusion CMR tractography of the heart, and to apply this method to quantify fiber architecture in the remote zone of remodeled hearts. Diffusion Tensor CMR of normal human, sheep, and rat hearts, as well as infarcted sheep hearts was performed ex vivo. Fiber tracts were generated with a fourth-order Runge-Kutta integration technique and classified statistically by the median, mean, maximum, or minimum helix angle (HA) along the tract. An index of tract coherence was derived from the relationship between these HA statistics. Histological validation was performed using phase-contrast microscopy. In normal hearts, the subendocardial and subepicardial myofibers had a positive and negative HA, respectively, forming a symmetric distribution around the midmyocardium. However, in the remote zone of the infarcted hearts, a significant positive shift in HA was observed. The ratio between negative and positive HA variance was reduced from 0.96 ± 0.16 in normal hearts to 0.22 ± 0.08 in the remote zone of the remodeled hearts (p layers of the myocardium. Tractography-based quantification, performed here for the first time in remodeled hearts, may provide a framework for assessing regional changes in the left ventricle following infarction.

  5. Automatic segmentation of myocardium from black-blood MR images using entropy and local neighborhood information.

    Directory of Open Access Journals (Sweden)

    Qian Zheng

    Full Text Available By using entropy and local neighborhood information, we present in this study a robust adaptive Gaussian regularizing Chan-Vese (CV model to segment the myocardium from magnetic resonance images with intensity inhomogeneity. By utilizing the circular Hough transformation (CHT our model is able to detect epicardial and endocardial contours of the left ventricle (LV as circles automatically, and the circles are used as the initialization. In the cost functional of our model, the interior and exterior energies are weighted by the entropy to improve the robustness of the evolving curve. Local neighborhood information is used to evolve the level set function to reduce the impact of the heterogeneity inside the regions and to improve the segmentation accuracy. An adaptive window is utilized to reduce the sensitivity to initialization. The Gaussian kernel is used to regularize the level set function, which can not only ensure the smoothness and stability of the level set function, but also eliminate the traditional Euclidean length term and re-initialization. Extensive validation of the proposed method on patient data demonstrates its superior performance over other state-of-the-art methods.

  6. Thallium 201 scintigraphy of the myocardium. A bibliographical survey for image optimisation

    International Nuclear Information System (INIS)

    Chatelier, Luc.

    1979-01-01

    At the request of a Nuclear Medicine Service we compiled a review of the literature on thallium 201 myocardium scintigraphy in order to define the optimum parameters for image acquisition; included also are the bibliograhical references of studies on the sensitivities, specificities and accuracies of this technique as compared with electrocardiography in the diagnosis and evaluation of ischemic heart diseases. This examination seems to have a part to play at all stages in the evaluation of ischemic heart diseases, whether for the detection (ischemia) emergency handling (thrombosis) or post-surgical checking (permeability of an aorto-coronary transplant) of these diseases, the great frequency and gravity of which have no longer to be proved. This study covers the whole period since thallium scintigraphy began (1970) until June 1978. Thallium seems to have a great future in cardiology and may be even in other fields since its use is quoted (in only a few publications as yet) for brain, kidney and pancreas scintigraphy [fr

  7. Discrepancy between microsphere and diffusible tracer estimates of perfusion to ischemic myocardium

    International Nuclear Information System (INIS)

    Yoshida, S.; Akizuki, S.; Gowski, D.; Downey, J.M.

    1985-01-01

    This study critically tests the ability of microspheres to accurately measure perfusion to ischemic myocardium. The left anterior descending coronary artery was cannulated and perfused with arterial blood. The perfusion line was clamped, and a sidearm between the clamp and the cannula was opened to the atmosphere, allowing blood to flow retrograde from the distal segment of the artery. Measurement of regional blood flow during retrograde flow diversion with 15-micron microspheres revealed essentially zero flow to the perfused segment (0.005 ml X min-1 X g-1). Measurements under the same conditions by either 86 Rb uptake or 133 Xe washout revealed that an appreciable perfusion of the tissue persisted during retrograde flow diversion (0.043 and 0.11 ml X min-1 X g-1, respectively, for the 2 methods). Thus, the authors have identified a condition during which microspheres indicate zero flow to the tissue but diffusible tracers can both be washed in and washed out at a brisk rate. They conclude that with simple occlusion there is a hidden component of perfusion to an ischemic zone that cannot be measured by microspheres, causing them to underestimate flow by about 25% in that condition

  8. Dynamic CT perfusion imaging of the myocardium: a technical note on improvement of image quality.

    Directory of Open Access Journals (Sweden)

    Daniela Muenzel

    Full Text Available OBJECTIVE: To improve image and diagnostic quality in dynamic CT myocardial perfusion imaging (MPI by using motion compensation and a spatio-temporal filter. METHODS: Dynamic CT MPI was performed using a 256-slice multidetector computed tomography scanner (MDCT. Data from two different patients-with and without myocardial perfusion defects-were evaluated to illustrate potential improvements for MPI (institutional review board approved. Three datasets for each patient were generated: (i original data (ii motion compensated data and (iii motion compensated data with spatio-temporal filtering performed. In addition to the visual assessment of the tomographic slices, noise and contrast-to-noise-ratio (CNR were measured for all data. Perfusion analysis was performed using time-density curves with regions-of-interest (ROI placed in normal and hypoperfused myocardium. Precision in definition of normal and hypoperfused areas was determined in corresponding coloured perfusion maps. RESULTS: The use of motion compensation followed by spatio-temporal filtering resulted in better alignment of the cardiac volumes over time leading to a more consistent perfusion quantification and improved detection of the extend of perfusion defects. Additionally image noise was reduced by 78.5%, with CNR improvements by a factor of 4.7. The average effective radiation dose estimate was 7.1±1.1 mSv. CONCLUSION: The use of motion compensation and spatio-temporal smoothing will result in improved quantification of dynamic CT MPI using a latest generation CT scanner.

  9. Transmural Variation and Anisotropy of Microvascular Flow Conductivity in the Rat Myocardium

    KAUST Repository

    Smith, Amy F.

    2014-05-28

    Transmural variations in the relationship between structural and fluid transport properties of myocardial capillary networks are determined via continuum modeling approaches using recent three-dimensional (3D) data on the microvascular structure. Specifically, the permeability tensor, which quantifies the inverse of the blood flow resistivity of the capillary network, is computed by volume-averaging flow solutions in synthetic networks with geometrical and topological properties derived from an anatomically-detailed microvascular data set extracted from the rat myocardium. Results show that the permeability is approximately ten times higher in the principal direction of capillary alignment (the "longitudinal" direction) than perpendicular to this direction, reflecting the strong anisotropy of the microvascular network. Additionally, a 30% increase in capillary diameter from subepicardium to subendocardium is shown to translate to a 130% transmural rise in permeability in the longitudinal capillary direction. This result supports the hypothesis that perfusion is preferentially facilitated during diastole in the subendocardial microvasculature to compensate for the severely-reduced systolic perfusion in the subendocardium.

  10. /sup 31/P-NMR studies of respiratory regulation in the intact myocardium

    Energy Technology Data Exchange (ETDEWEB)

    From, A H.L.; Petein, M A; Zimmer, S W; Michurski, S P; Ugurbil, K

    1986-10-06

    The mechanism by which mitochondrial respiration is coupled to ATP consumption in intact tissues is unclear. The authors determined the relationship between high-energy phosphate levels and oxygen consumption rate in rat hearts operating over a range of workloads and perfused with different substrates. With pyruvate + glucose perfusion, ADP levels were in general very low, and varied with MVO/sub 2/ yielding an apparent K/sub m/ of 25 +- 5 ..mu..M, suggesting regulation of oxidative phosphorylation through availability of ADP. In contrast, with glucose perfusion in the presence or absence of insulin, ADP levels, ADP/ATP ratio or the phosphate potential were relatively constant over the workload range examined and generally not correlated with alterations in MVO/sub 2/; it is suggested that under these conditions, carbon substrate delivery to the mitochondria may control mitochondrial respiration. The common feature of both of the suggested regulatory mechanisms is substrate limitation which, however, is exercised at different metabolic points depending on the carbon substrate available to the myocardium. 19 refs.; 2 figs.; 1 table.

  11. An interesting case of cryptogenic stroke in a young man due to left ventricular non-compaction: role of cardiac MRI in the accurate diagnosis.

    Science.gov (United States)

    Kannan, Arun; Das, Anindita; Janardhanan, Rajesh

    2014-06-24

    A 28-year-old man arrived for an outpatient cardiac MRI (CMR) study to evaluate cardiac structure. At the age of 24 the patient presented with acute onset expressive aphasia and was diagnosed with ischaemic stroke. Echocardiography at that time was reported as 'apical wall thickening consistent with apical hypertrophic cardiomyopathy'. CMR revealed a moderately dilated left ventricle with abnormal appearance of the left ventricular (LV) apical segments. Further evaluation was consistent with a diagnosis of LV non-compaction (LVNC) cardiomyopathy with a ratio of non-compacted to compacted myocardium measuring 3. There was extensive delayed hyperenhancement signal involving multiple segments representing a significant myocardial scar which is shown to have a prognostic role. Our patient, with no significant cerebrovascular risk factors, would likely have had an embolic stroke. This case demonstrates the role of CMR in accurately diagnosing LVNC in a patient with young stroke where prior echocardiography was non-diagnostic. 2014 BMJ Publishing Group Ltd.

  12. Appearance of high signal intensity and gadolinium-DTPA contrast enhancement in hypertrophied myocardium by magnetic resonance imaging

    International Nuclear Information System (INIS)

    Nishimura, Tsunehiko; Yamada, Naoaki; Nagata, Seiki

    1989-01-01

    This study was undertaken to examine the potential role of magnetic resonance imaging (MRI) for evaluating myocardial tissue characterization in hypertrophic cardiomyopathy (HCM). ECG-gated MRI images were acquired in 32 HCM patients and 30 patients with hypertensive heart disease (HHD), using a 1.5 T superconducting magnet system. The thickened areas were depicted as high signal intensities in the septum of 12 HCM patients (38%) and the endocardium of 5 HHD patients (17%). Echocardiography revealed that MRI appearance of high signal intensity was associated with more thickened myocardial wall. For evaluable 16 patients receiving i.v. injection of Gd-DTPA in a dose of 0.1 mM/kg, enhancement effects were observed in 10 patients (63%). High signal intensity appearing in the hypertrophied myocardium, as well as contrast enhancement, may not be characteristic of HCM, but reflect the likelihood of myocardial degeneration associated with the hypertrophied myocardium. Although MRI may not be capable of differentiating tissue characterization in HCM from that in HHD, it may provide different information about tissue characterization in the hypertrophied myocardium from that obtained by other techniques. (N.K.)

  13. Exercise Increases Cystathionine-γ-lyase Expression and Decreases the Status of Oxidative Stress in Myocardium of Ovariectomized Rats.

    Science.gov (United States)

    Tang, Zhiping; Wang, Yujun; Zhu, Xiaoyan; Ni, Xin; Lu, Jianqiang

    2016-01-01

    Exercise could be a therapeutic approach for cardiovascular dysfunction induced by estrogen deficiency. Our previous study has shown that estrogen maintains cystathionine-γ-lyase (CSE) expression and inhibits oxidative stress in the myocardium of female rats. In the present study, we investigated whether exercise improves CSE expression and oxidative stress status and ameliorates isoproterenol (ISO)-induced cardiac damage in ovariectomized (OVX) rats. The results showed that treadmill training restored the ovariectomy-induced reduction of CSE and estrogen receptor (ER)α and decrease of total antioxidant capacity (T-AOC) and increase of malondialdehyde (MDA). The level of CSE was positively correlated to T-AOC and ERα while inversely correlated to MDA. OVX rats showed increases in the serum levels of creatine kinase (CK) and lactate dehydrogenase (LDH) and the percentage of TUNEL staining in myocardium upon ISO insult compared to sham rats. Exercise training significantly reduced the serum levels of LDH and CK and the percentage of TUNEL staining in myocardium upon ISO insult in OVX rats. In cultured cardiomyocytes, ISO treatment decreased cell viability and increased LDH release, while overexpression of CSE increased cell viability and decreased LDH release in the cells upon ISO insult. The results suggest that exercise training improves the oxidative stress status and ameliorates the cardiac damage induced by oxidative stress in OVX rats. The improvement of oxidative stress status by exercise might be at least partially due to upregulation of CSE/H2S signaling.

  14. Observation of 99Tcm-MIBI uptake of ischemic myocardium in dog models after left circumflex coronary artery constriction

    International Nuclear Information System (INIS)

    Cheng Guanghua; Dai Yunhai; Wu Kefang; Xu Quanfeng

    2008-01-01

    Objective: To observe 99 Tc m -MIBI uptake of ischemic myocardium at different times (1h, 4h) in dog models after left circumflex coronary artery constriction. Methods: 12 dog models of coronary artery stenosis were prepared by left circumflex coronary ligation, and were given injection of 99 Tc m -MIBI at the dosage of 185 MBq (5 mCi). Six models were sacrificed at one hour and four hours after the injection respectively. Radio-uptake in about 100 mg myocardium from both ischemic and non-ischemic sites were measured with r-counter. Results: No significant differences were found between ratios of radioactive count of ischemic over normal myocardial tissues at 1h and 4h after injection of 99 Tc m -MIBI (0.726±0.054 and 0.673±0.080, respective, t=1.3452, P >0.05). Conclusion: The extension of post-injection time would not increase 99 Tc m -MIBI uptake in ischemic myocardium. (authors)

  15. Discovery of Radioiodinated Monomeric Anthraquinones as a Novel Class of Necrosis Avid Agents for Early Imaging of Necrotic Myocardium.

    Science.gov (United States)

    Wang, Qin; Yang, Shengwei; Jiang, Cuihua; Li, Jindian; Wang, Cong; Chen, Linwei; Jin, Qiaomei; Song, Shaoli; Feng, Yuanbo; Ni, Yicheng; Zhang, Jian; Yin, Zhiqi

    2016-02-16

    Assessment of myocardial viability is deemed necessary to aid in clinical decision making whether to recommend revascularization therapy for patients with myocardial infarction (MI). Dianthraquinones such as hypericin (Hyp) selectively accumulate in necrotic myocardium, but were unsuitable for early imaging after administration to assess myocardial viability. Since dianthraquinones can be composed by coupling two molecules of monomeric anthraquinone and the active center can be found by splitting chemical structure, we propose that monomeric anthraquinones may be effective functional groups for necrosis targetability. In this study, eight radioiodinated monomeric anthraquinones were evaluated as novel necrosis avid agents (NAAs) for imaging of necrotic myocardium. All (131)I-anthraquinones showed high affinity to necrotic tissues and (131)I-rhein emerged as the most promising compound. Infarcts were visualized on SPECT/CT images at 6 h after injection of (131)I-rhein, which was earlier than that with (131)I-Hyp. Moreover, (131)I-rhein showed satisfactory heart-to-blood, heart-to-liver and heart-to-lung ratios for obtaining images of good diagnostic quality. (131)I-rhein was a more promising "hot spot imaging" tracer for earlier visualization of necrotic myocardium than (131)I-Hyp, which supported further development of radiopharmaceuticals based on rhein for SPECT/CT ((123)I and (99m)Tc) or PET/CT imaging ((18)F and (124)I) of myocardial necrosis.

  16. follow-up of patients with arrhythmogenic right ventricular

    African Journals Online (AJOL)

    was sudden, 1 patient died due to left ventricular failure, and ... Arrhythmogenic right ventricular cardiomyopathy/ dysplasia .... hypertension and from atrial fibrillation that developed 2.4 .... of left ventricular function was global without regional ..... 99mTc he brain si before a acid (G minute his sem next 3 - his sem showed.

  17. Left Ventricular Geometry In Nigerians With Type II Diabetes Mellitus ...

    African Journals Online (AJOL)

    Background: Left ventricular hypertrophy is independently associated with increased incidence of cardiovascular disease, cardiovascular and all cause mortality. In a relatively healthy hypertensive adult population, type II diabetes is associated with higher left ventricular mass, concentric left ventricular geometry and lower ...

  18. Genetic modification of mesenchymal stem cells overexpressing CCR1 increases cell viability, migration, engraftment, and capillary density in the injured myocardium.

    Science.gov (United States)

    Huang, Jing; Zhang, Zhiping; Guo, Jian; Ni, Aiguo; Deb, Arjun; Zhang, Lunan; Mirotsou, Maria; Pratt, Richard E; Dzau, Victor J

    2010-06-11

    Although mesenchymal stem cell (MSC) transplantation has been shown to promote cardiac repair in acute myocardial injury in vivo, its overall restorative capacity appears to be restricted mainly because of poor cell viability and low engraftment in the ischemic myocardium. Specific chemokines are upregulated in the infarcted myocardium. However the expression levels of the corresponding chemokine receptors (eg, CCR1, CXCR2) in MSCs are very low. We hypothesized that this discordance may account for the poor MSC engraftment and survival. To determine whether overexpression of CCR1 or CXCR2 chemokine receptors in MSCs augments their cell survival, migration and engraftment after injection in the infarcted myocardium. Overexpression of CCR1, but not CXCR2, dramatically increased chemokine-induced murine MSC migration and protected MSC from apoptosis in vitro. Moreover, when MSCs were injected intramyocardially one hour after coronary artery ligation, CCR1-MSCs accumulated in the infarcted myocardium at significantly higher levels than control-MSCs or CXCR2-MSCs 3 days postmyocardial infarction (MI). CCR1-MSC-injected hearts exhibited a significant reduction in infarct size, reduced cardiomyocytes apoptosis and increased capillary density in injured myocardium 3 days after MI. Furthermore, intramyocardial injection of CCR1-MSCs prevented cardiac remodeling and restored cardiac function 4 weeks after MI. Our results demonstrate the in vitro and in vivo salutary effects of genetic modification of stem cells. Specifically, overexpression of chemokine receptor enhances the migration, survival and engraftment of MSCs, and may provide a new therapeutic strategy for the injured myocardium.

  19. Flecainide Therapy Reduces Exercise-Induced Ventricular Arrhythmias in Patients With Catecholaminergic Polymorphic Ventricular Tachycardia

    NARCIS (Netherlands)

    van der Werf, Christian; Kannankeril, Prince J.; Sacher, Frederic; Krahn, Andrew D.; Viskin, Sami; Leenhardt, Antoine; Shimizu, Wataru; Sumitomo, Naokata; Fish, Frank A.; Bhuiyan, Zahurul A.; Willems, Albert R.; van der Veen, Maurits J.; Watanabe, Hiroshi; Laborderie, Julien; Haïssaguerre, Michel; Knollmann, Björn C.; Wilde, Arthur A. M.

    2011-01-01

    Objectives This study evaluated the efficacy and safety of flecainide in addition to conventional drug therapy in patients with catecholaminergic polymorphic ventricular tachycardia (CPVT). Background CPVT is an inherited arrhythmia syndrome caused by gene mutations that destabilize cardiac

  20. Acute Right Ventricular Dysfunction Complicating Prolonged ...

    African Journals Online (AJOL)

    We report a case of transient right ventricular dysfunction associated with prolonged cardiac tamponade, an unusual complication of uncertain etiology. We believe that in this case dynamic coronary flow restriction resulted in ischemic injury and stunning of the right ventricle. Other possible causes are briefly reviewed. Right ...

  1. Left ventricular hypertrophy : virtuous intentions, malign consequences

    NARCIS (Netherlands)

    Pokharel, S; Sharma, UC; Pinto, YM

    Left ventricular hypertrophy (LVH) is currently the focus of intense cardiovascular research, with the resultant rapid evolution of novel concepts relating to its exceedingly complex pathophysiology. In addition to the alterations in signal transduction and disturbances in Ca2+ homeostasis, there

  2. Left ventricular hypertrophy: virtuous intentions, malign consequences

    NARCIS (Netherlands)

    Pokharel, Saraswati; Sharma, Umesh C.; Pinto, Yigal M.

    2003-01-01

    Left ventricular hypertrophy (LVH) is currently the focus of intense cardiovascular research, with the resultant rapid evolution of novel concepts relating to its exceedingly complex pathophysiology. In addition to the alterations in signal transduction and disturbances in Ca(2+) homeostasis, there

  3. Right ventricular myxoma with heart failure

    International Nuclear Information System (INIS)

    Nuri, M.M.H.; Naseem, A.; Raza, A.; Ahmad, W.; Raja, M.K.; Ahmad, A.; Rasheed, A.; Gohar, A.

    2005-01-01

    Cardiac myxomas are histologically benign tumors but they may be lethal because of their strategic position. These are mostly located in the left atrium and uncommonly in the right atrium. We report a case of a large right ventricular myxoma presenting with heart failure. (author)

  4. Radionuclide analysis of right and left ventricular response to exercise in patients with atrial and ventricular septal defects

    International Nuclear Information System (INIS)

    Peter, C.A.; Bowyer, K.; Jones, R.H.

    1983-01-01

    In patients with ventricular or atrial septal defect, the ventricle which is chronically volume overloaded might not appropriately respond to increased demand for an augmentation in output and thereby might limit total cardiac function. In this study we simultaneously measured right and left ventricular response to exercise in 10 normal individuals, 10 patients with ventricular septal defect (VSD), and 10 patients with atrial septal defect (ASD). The normal subjects increased both right and left ventricular ejection fraction, end-diastolic volume, and stroke volume to achieve a higher cardiac output during exercise. Patients with VSD failed to increase right ventricular ejection fraction, but increased right ventricular end-diastolic volume and stroke volume. Left ventricular end-diastolic volume did not increase in these patients but ejection fraction, stroke volume, and forward left ventricular output achieved during exercise were comparable to the response observed in healthy subjects. In the patients with ASD, no rest-to-exercise change occurred in either right ventricular ejection fraction, end-diastolic volume, or stroke volume. In addition, left ventricular end-diastolic volume failed to increase, and despite an increase in ejection fraction, left ventricular stroke volume remained unchanged from rest to exercise. Therefore, cardiac output was augmented only by the heart rate increase in these patients. Right ventricular function appeared to be the major determinant of total cardiac output during exercise in patients with cardiac septal defects and left-to-right shunt

  5. Innate collateral segments are predominantly present in the subendocardium without preferential connectivity within the left ventricular wall

    Science.gov (United States)

    van Horssen, Pepijn; Siebes, Maria; Spaan, Jos A E; Hoefer, Imo E; van den Wijngaard, Jeroen P H M

    2014-01-01

    Functional collateral vessels often stem from outward remodelling of pre-existing connections between perfusion territories. Knowledge of the distribution and morphology of innate collateral connections may help in identifying myocardial areas with protection against risk for ischaemia. The coronary network of six healthy canine hearts was investigated with an imaging cryomicrotome. Innate collateral connections ranged from 286 to 1015 μm in diameter. Left ventricular collateral density (number per gram of tissue) was about five in the subendocardium vs. 2.5 in the mid-myocardium (P collateral connections were oriented parallel to the long axis of the heart. For the major coronary arteries, five times more intracoronary than intercoronary connections were found, while their median diameter and interquartile range were not significantly different, at 96.1 (16.9) vs. 94.7 (18.9) μm. Collateral vessels connecting crowns from sister branches from a stem are denoted intercrown connections and those within crowns intracrown connections. The number of intercrown connections was related to the mean tissue weight of the crowns (y = 0.73x − 0.33, r2 = 0.85, P collateral diameter and length were independent of the tissue volumes bridged. We conclude that connectivity and morphology of the innate collateral network are distributed with no preference for intra-or intercrown connections, independent of stem diameter, including epicardial arteries. This renders all sites of the myocardium equally protected in case of coronary artery disease. The orientation of subendocardial collateral vessels indicates the longitudinal direction of subendocardial collateral flow. PMID:24366260

  6. Innate collateral segments are predominantly present in the subendocardium without preferential connectivity within the left ventricular wall.

    Science.gov (United States)

    van Horssen, Pepijn; Siebes, Maria; Spaan, Jos A E; Hoefer, Imo E; van den Wijngaard, Jeroen P H M

    2014-03-01

    Functional collateral vessels often stem from outward remodelling of pre-existing connections between perfusion territories. Knowledge of the distribution and morphology of innate collateral connections may help in identifying myocardial areas with protection against risk for ischaemia. The coronary network of six healthy canine hearts was investigated with an imaging cryomicrotome. Innate collateral connections ranged from 286 to 1015 μm in diameter. Left ventricular collateral density (number per gram of tissue) was about five in the subendocardium vs. 2.5 in the mid-myocardium (P collateral connections were oriented parallel to the long axis of the heart. For the major coronary arteries, five times more intracoronary than intercoronary connections were found, while their median diameter and interquartile range were not significantly different, at 96.1 (16.9) vs. 94.7 (18.9) μm. Collateral vessels connecting crowns from sister branches from a stem are denoted intercrown connections and those within crowns intracrown connections. The number of intercrown connections was related to the mean tissue weight of the crowns (y = 0.73x - 0.33, r2 = 0.85, P collateral diameter and length were independent of the tissue volumes bridged. We conclude that connectivity and morphology of the innate collateral network are distributed with no preference for intra- or intercrown connections, independent of stem diameter, including epicardial arteries. This renders all sites of the myocardium equally protected in case of coronary artery disease. The orientation of subendocardial collateral vessels indicates the longitudinal direction of subendocardial collateral flow.

  7. High-Salt Intake Suppressed MicroRNA-133a Expression in Dahl SS Rat Myocardium

    Science.gov (United States)

    Guo, Tong-Shuai; Zhang, Jie; Mu, Jian-Jun; Liu, Fu-Qiang; Yuan, Zu-Yi; Ren, Ke-Yu; Wang, Dan

    2014-01-01

    Salt-sensitive individuals show earlier and more serious cardiac damage than nonsalt-sensitive ones. Some studies have suggested that microRNA-133a could reduce cardiac hypertrophy and myocardial fibrosis. The current study aims to investigate the different functions of high-salt intake on salt-sensitive (SS) rats and Sprague-Dawley (SD) rats and the involvement of microRNA-133a in these roles. After high-salt intervention, the left ventricular mass (LVW) and left ventricular mass index (LVMI) of the salt-sensitive high salt (SHS) group were obviously higher than those of the salt-sensitive low salt (SLS) group. However, the difference between the Sprague-Dawley high salt (DHS) group and the Sprague-Dawley low salt (DLS) group was not significant. Compared with SLS group, collagen I and connective tissue growth factor (CTGF) in the heart of SHS group were significantly higher, whereas no statistical difference was observed between the DHS group and the DLS group. Compared with low-salt diet, microRNA-133a in the heart of both strains were significantly decreased, but that in the SHS group decreased more significantly. These results suggest that high salt intervention could down-regulate the expression of myocardial microRNA-133a, which may be one of the mechanisms involved in myocardial fibrosis in salt-sensitive hypertension. PMID:24937684

  8. High-Salt Intake Suppressed MicroRNA-133a Expression in Dahl SS Rat Myocardium

    Directory of Open Access Journals (Sweden)

    Tong-Shuai Guo

    2014-06-01

    Full Text Available Salt-sensitive individuals show earlier and more serious cardiac damage than nonsalt-sensitive ones. Some studies have suggested that microRNA-133a could reduce cardiac hypertrophy and myocardial fibrosis. The current study aims to investigate the different functions of high-salt intake on salt-sensitive (SS rats and Sprague-Dawley (SD rats and the involvement of microRNA-133a in these roles. After high-salt intervention, the left ventricular mass (LVW and left ventricular mass index (LVMI of the salt-sensitive high salt (SHS group were obviously higher than those of the salt-sensitive low salt (SLS group. However, the difference between the Sprague-Dawley high salt (DHS group and the Sprague-Dawley low salt (DLS group was not significant. Compared with SLS group, collagen I and connective tissue growth factor (CTGF in the heart of SHS group were significantly higher, whereas no statistical difference was observed between the DHS group and the DLS group. Compared with low-salt diet, microRNA-133a in the heart of both strains were significantly decreased, but that in the SHS group decreased more significantly. These results suggest that high salt intervention could down-regulate the expression of myocardial microRNA-133a, which may be one of the mechanisms involved in myocardial fibrosis in salt-sensitive hypertension.

  9. Hollow mandrin facilitates external ventricular drainage placement.

    Science.gov (United States)

    Heese, O; Regelsberger, J; Kehler, U; Westphal, M

    2005-07-01

    Placement of ventricular catheters is a routine procedure in neurosurgery. Ventricle puncture is done using a flexible ventricular catheter stabilised by a solid steel mandrin in order to improve stability during brain penetration. A correct catheter placement is confirmed after removing the solid steel mandrin by observation of cerebrospinal fluid (CSF) flow out of the flexible catheter. Incorrect placement makes further punctures necessary. The newly developed device allows CSF flow observation during the puncture procedure and in addition precise intracranial pressure (ICP) measurement. The developed mandrin is hollow with a blunt tip. On one side 4-5 small holes with a diameter of 0.8 mm are drilled corresponding exactly with the holes in the ventricular catheter, allowing CSF to pass into the hollow mandrin as soon as the ventricle is reached. By connecting a small translucent tube at the distal portion of the hollow mandrin ICP can be measured without loss of CSF. The system has been used in 15 patients with subarachnoid haemorrhage (SAH) or intraventricular haemeorrhage (IVH) and subsequent hydrocephalus. The new system improved the external ventricular drainage implantation procedure. In all 15 patients catheter placement was correct. ICP measurement was easy to perform immediately at ventricle puncture. In 4 patients at puncture no spontaneous CSF flow was observed, therefore by connecting a syringe and gentle aspiration of CSF correct placement was confirmed in this unexpected low pressure hydrocephalus. Otherwise by using the conventional technique further punctures would have been necessary. Advantages of the new technique are less puncture procedures with a lower risk of damage to neural structures and reduced risk of intracranial haemorrhages. Implantation of the ventricular catheter to far into the brain can be monitored and this complication can be overcome. Using the connected pressure monitoring tube an exact measurement of the opening

  10. Left ventricular function in chronic aortic regurgitation

    International Nuclear Information System (INIS)

    Iskandrian, A.S.; Hakki, A.H.; Manno, B.; Amenta, A.; Kane, S.A.

    1983-01-01

    Left ventricular performance was determined in 42 patients with moderate or severe aortic regurgitation during upright exercise by measuring left ventricular ejection fraction and volume with radionuclide ventriculography. Classification of the patients according to exercise tolerance showed that patients with normal exercise tolerance (greater than or equal to 7.0 minutes) had a significantly higher ejection fraction at rest (probability [p] . 0.02) and during exercise (p . 0.0002), higher cardiac index at exercise (p . 0.0008) and lower exercise end-systolic volume (p . 0.01) than did patients with limited exercise tolerance. Similar significant differences were noted in younger patients compared with older patients in ejection fraction at rest and exercise (both p . 0.001) and cardiac index at rest (p . 0.03) and exercise (p . 0.0005). The end-diastolic volume decreased during exercise in 60% of the patients. The patients with a decrease in volume were significantly younger and had better exercise tolerance and a larger end-diastolic volume at rest than did patients who showed an increase in volume. The mean corrected left ventricular end-diastolic radius/wall thickness ratio was significantly greater in patients with abnormal than in those with normal exercise reserve (mean +/- standard deviation 476 +/- 146 versus 377 +/- 92 mm Hg, p less than 0.05). Thus, in patients with chronic aortic regurgitation: 1) left ventricular systolic function during exercise was related to age, exercise tolerance and corrected left ventricular end-diastolic radius/wall thickness ratio, and 2) the end-diastolic volume decreased during exercise, especially in younger patients and patients with normal exercise tolerance or a large volume at rest

  11. Mammalian Synthetic Biology: Time for Big MACs.

    Science.gov (United States)

    Martella, Andrea; Pollard, Steven M; Dai, Junbiao; Cai, Yizhi

    2016-10-21

    The enabling technologies of synthetic biology are opening up new opportunities for engineering and enhancement of mammalian cells. This will stimulate diverse applications in many life science sectors such as regenerative medicine, development of biosensing cell lines, therapeutic protein production, and generation of new synthetic genetic regulatory circuits. Harnessing the full potential of these new engineering-based approaches requires the design and assembly of large DNA constructs-potentially up to chromosome scale-and the effective delivery of these large DNA payloads to the host cell. Random integration of large transgenes, encoding therapeutic proteins or genetic circuits into host chromosomes, has several drawbacks such as risks of insertional mutagenesis, lack of control over transgene copy-number and position-specific effects; these can compromise the intended functioning of genetic circuits. The development of a system orthogonal to the endogenous genome is therefore beneficial. Mammalian artificial chromosomes (MACs) are functional, add-on chromosomal elements, which behave as normal chromosomes-being replicating and portioned to daughter cells at each cell division. They are deployed as useful gene expression vectors as they remain independent from the host genome. MACs are maintained as a single-copy and can accommodate multiple gene expression cassettes of, in theory, unlimited DNA size (MACs up to 10 megabases have been constructed). MACs therefore enabled control over ectopic gene expression and represent an excellent platform to rapidly prototype and characterize novel synthetic gene circuits without recourse to engineering the host genome. This review describes the obstacles synthetic biologists face when working with mammalian systems and how the development of improved MACs can overcome these-particularly given the spectacular advances in DNA synthesis and assembly that are fuelling this research area.

  12. Dedifferentiation and proliferation of mammalian cardiomyocytes.

    Directory of Open Access Journals (Sweden)

    Yiqiang Zhang

    2010-09-01

    Full Text Available It has long been thought that mammalian cardiomyocytes are terminally-differentiated and unable to proliferate. However, myocytes in more primitive animals such as zebrafish are able to dedifferentiate and proliferate to regenerate amputated cardiac muscle.Here we test the hypothesis that mature mammalian cardiomyocytes retain substantial cellular plasticity, including the ability to dedifferentiate, proliferate, and acquire progenitor cell phenotypes. Two complementary methods were used: 1 cardiomyocyte purification from rat hearts, and 2 genetic fate mapping in cardiac explants from bi-transgenic mice. Cardiomyocytes isolated from rodent hearts were purified by multiple centrifugation and Percoll gradient separation steps, and the purity verified by immunostaining and RT-PCR. Within days in culture, purified cardiomyocytes lost their characteristic electrophysiological properties and striations, flattened and began to divide, as confirmed by proliferation markers and BrdU incorporation. Many dedifferentiated cardiomyocytes went on to express the stem cell antigen c-kit, and the early cardiac transcription factors GATA4 and Nkx2.5. Underlying these changes, inhibitory cell cycle molecules were suppressed in myocyte-derived cells (MDCs, while microRNAs known to orchestrate proliferation and pluripotency increased dramatically. Some, but not all, MDCs self-organized into spheres and re-differentiated into myocytes and endothelial cells in vitro. Cell fate tracking of cardiomyocytes from 4-OH-Tamoxifen-treated double-transgenic MerCreMer/ZEG mouse hearts revealed that green fluorescent protein (GFP continues to be expressed in dedifferentiated cardiomyocytes, two-thirds of which were also c-kit(+.Contradicting the prevailing view that they are terminally-differentiated, postnatal mammalian cardiomyocytes are instead capable of substantial plasticity. Dedifferentiation of myocytes facilitates proliferation and confers a degree of stemness

  13. Mammalian niche conservation through deep time.

    Directory of Open Access Journals (Sweden)

    Larisa R G DeSantis

    Full Text Available Climate change alters species distributions, causing plants and animals to move north or to higher elevations with current warming. Bioclimatic models predict species distributions based on extant realized niches and assume niche conservation. Here, we evaluate if proxies for niches (i.e., range areas are conserved at the family level through deep time, from the Eocene to the Pleistocene. We analyze the occurrence of all mammalian families in the continental USA, calculating range area, percent range area occupied, range area rank, and range polygon centroids during each epoch. Percent range area occupied significantly increases from the Oligocene to the Miocene and again from the Pliocene to the Pleistocene; however, mammalian families maintain statistical concordance between rank orders across time. Families with greater taxonomic diversity occupy a greater percent of available range area during each epoch and net changes in taxonomic diversity are significantly positively related to changes in percent range area occupied from the Eocene to the Pleistocene. Furthermore, gains and losses in generic and species diversity are remarkably consistent with ~2.3 species gained per generic increase. Centroids demonstrate southeastern shifts from the Eocene through the Pleistocene that may correspond to major environmental events and/or climate changes during the Cenozoic. These results demonstrate range conservation at the family level and support the idea that niche conservation at higher taxonomic levels operates over deep time and may be controlled by life history traits. Furthermore, families containing megafauna and/or terminal Pleistocene extinction victims do not incur significantly greater declines in range area rank than families containing only smaller taxa and/or only survivors, from the Pliocene to Pleistocene. Collectively, these data evince the resilience of families to climate and/or environmental change in deep time, the absence of

  14. Mammalian developmental genetics in the twentieth century.

    Science.gov (United States)

    Artzt, Karen

    2012-12-01

    This Perspectives is a review of the breathtaking history of mammalian genetics in the past century and, in particular, of the ways in which genetic thinking has illuminated aspects of mouse development. To illustrate the power of that thinking, selected hypothesis-driven experiments and technical advances are discussed. Also included in this account are the beginnings of mouse genetics at the Bussey Institute, Columbia University, and The Jackson Laboratory and a retrospective discussion of one of the classic problems in developmental genetics, the T/t complex and its genetic enigmas.

  15. Nutrient acquisition strategies of mammalian cells.

    Science.gov (United States)

    Palm, Wilhelm; Thompson, Craig B

    2017-06-07

    Mammalian cells are surrounded by diverse nutrients, such as glucose, amino acids, various macromolecules and micronutrients, which they can import through transmembrane transporters and endolysosomal pathways. By using different nutrient sources, cells gain metabolic flexibility to survive periods of starvation. Quiescent cells take up sufficient nutrients to sustain homeostasis. However, proliferating cells depend on growth-factor-induced increases in nutrient uptake to support biomass formation. Here, we review cellular nutrient acquisition strategies and their regulation by growth factors and cell-intrinsic nutrient sensors. We also discuss how oncogenes and tumour suppressors promote nutrient uptake and thereby support the survival and growth of cancer cells.

  16. Preservation of mammalian germ plasm by freezing

    Energy Technology Data Exchange (ETDEWEB)

    Mazur, P.

    1978-01-01

    Embryos of several mammalian species can be frozen to -196/sup 0/C (or below) by procedures that result in the thawed embryos being indistinguishable from their unfrozen counterparts. The survival often exceeds 90%, and in liquid nitrogen it should remain at that high level for centuries. Sublethal biochemical changes are also precluded at -196/sup 0/C. No developmental abnormalities have been detected in mouse offspring derived from frozen-thawed embryos, and, since all the manipulations are carried out on the preimplantation stages, none would be expected.

  17. Mammalian cell culture capacity for biopharmaceutical manufacturing.

    Science.gov (United States)

    Ecker, Dawn M; Ransohoff, Thomas C

    2014-01-01

    : With worldwide sales of biopharmaceuticals increasing each year and continuing growth on the horizon, the manufacture of mammalian biopharmaceuticals has become a major global enterprise. We describe the current and future industry wide supply of manufacturing capacity with regard to capacity type, distribution, and geographic location. Bioreactor capacity and the use of single-use products for biomanufacturing are also profiled. An analysis of the use of this capacity is performed, including a discussion of current trends that will influence capacity growth, availability, and utilization in the coming years.

  18. Mammalian Gravity Receptors: Structure and Metabolism

    Science.gov (United States)

    Ross, M. D.

    1985-01-01

    Calcium metabolism in mammalian gravity receptors is examined. To accomplish this objective it is necessary to study both the mineral deposits of the receptors, the otoconia, and the sensory areas themselves, the saccular and utricular maculas. The main focus was to elucidate the natures of the organic and inorganic phases of the crystalline masses, first in rat otoconia but more recently in otoliths and otoconia of a comparative series of vertebrates. Some of the ultrastructural findings in rat maculas, however, have prompted a more thorough study of the organization of the hair cells and innervation patterns in graviceptors.

  19. Echocardiographic left ventricular masses in distance runners and weight lifters

    Science.gov (United States)

    Longhurst, J. C.; Gonyea, W. J.; Mitchell, J. H.; Kelly, A. R.

    1980-01-01

    The relationships of different forms of exercise training to left ventricular mass and body mass are investigated by echocardiographic studies of weight lifters, long-distance runners, and comparatively sized untrained control subjects. Left ventricular mass determinations by the Penn convention reveal increased absolute left ventricular masses in long-distance runners and competitive weight lifters with respect to controls matched for age, body weight, and body surface area, and a significant correlation between ventricular mass and lean body mass. When normalized to lean body mass, the ventricular masses of distance runners are found to be significantly higher than those of the other groups, suggesting that dynamic training elevates left ventricular mass compared to static training and no training, while static training increases ventricular mass only to the extent that lean body mass is increased.

  20. Two-dimensional echocardiographic features of right ventricular infarction

    International Nuclear Information System (INIS)

    D'Arcy, B.; Nanda, N.C.

    1982-01-01

    Real-time, two-dimensional echocardiographic studies were performed in 10 patients with acute myocardial infarction who had clinical features suggestive of right ventricular involvement. All patients showed right ventricular wall motion abnormalities. In the four-chamber view, seven patients showed akinesis of the entire right ventricular diaphragmatic wall and three showed akinesis of segments of the diaphragmatic wall. Segmental dyskinetic areas involving the right ventricular free wall were identified in four patients. One patient showed a large right ventricular apical aneurysm. Other echocardiographic features included enlargement of the right ventricle in eight cases, paradoxical ventricular septal motion in seven cases, tricuspid incompetence in eight cases, dilation of the stomach in four cases and localized pericardial effusion in two cases. Right ventricular infarction was confirmed by radionuclide methods in seven patients, at surgery in one patient and at autopsy in two patients

  1. Fiber architecture in remodeled myocardium revealed with a quantitative diffusion CMR tractography framework and histological validation

    Directory of Open Access Journals (Sweden)

    Mekkaoui Choukri

    2012-10-01

    Full Text Available Abstract Background The study of myofiber reorganization in the remote zone after myocardial infarction has been performed in 2D. Microstructural reorganization in remodeled hearts, however, can only be fully appreciated by considering myofibers as continuous 3D entities. The aim of this study was therefore to develop a technique for quantitative 3D diffusion CMR tractography of the heart, and to apply this method to quantify fiber architecture in the remote zone of remodeled hearts. Methods Diffusion Tensor CMR of normal human, sheep, and rat hearts, as well as infarcted sheep hearts was performed ex vivo. Fiber tracts were generated with a fourth-order Runge-Kutta integration technique and classified statistically by the median, mean, maximum, or minimum helix angle (HA along the tract. An index of tract coherence was derived from the relationship between these HA statistics. Histological validation was performed using phase-contrast microscopy. Results In normal hearts, the subendocardial and subepicardial myofibers had a positive and negative HA, respectively, forming a symmetric distribution around the midmyocardium. However, in the remote zone of the infarcted hearts, a significant positive shift in HA was observed. The ratio between negative and positive HA variance was reduced from 0.96 ± 0.16 in normal hearts to 0.22 ± 0.08 in the remote zone of the remodeled hearts (p Conclusions A significant reorganization of the 3D fiber continuum is observed in the remote zone of remodeled hearts. The positive (rightward shift in HA in the remote zone is greatest in the subepicardium, but involves all layers of the myocardium. Tractography-based quantification, performed here for the first time in remodeled hearts, may provide a framework for assessing regional changes in the left ventricle following infarction.

  2. Do indices of coronary conductance after reperfusion reflect the extent of salvaged myocardium?

    Science.gov (United States)

    Shibata, Takahiro; Watanabe, Hisashi; Tsurusaki, Tetsushi; Minai, Kousuke; Ogawa, Takayuki; Iwano, Keiji; Tamura, Tetsutarou; Yoshida, Satoshi; Mutou, Makoto; Imai, Kamon; Horie, Toshinobu; Mochizuki, Seibu

    2004-05-01

    Existing indices of coronary conductance (hyperemic flow-versus-pressure slope index, FPSI, and zero flow pressure, Pzf) have been developed as measures of microcoronary resistance. These indices, however, refer to cases of normal hearts, and there are no reports studying these indices following acute myocardial infarction. In this study, we investigated whether FPSI and Pzf truly measure the extent of myocardial salvage after successful reperfusion therapy. We also developed a new index of zero pressure flow, Fzp. Nineteen patients who underwent successful reperfusion therapy to the proximal portion of the left anterior descending artery (LAD) were studied. After successful reperfusion therapy, a Doppler wire was placed into the LAD. Aortic pressure was recorded in real time. Results from the aortic pressure and flow meter were combined to produce FPSI, Pzf, and Fzp. All cases underwent a resting thallium (Tl) and BMIPP scintigram within five days of successful reperfusion therapy. Infarcted myocardium was estimated using a severity score calculated from the Tl scintigraphy (TlSS), and the BMIPP (BMIPPSS) was estimated using a severity score. Patients with a TlSS/BMIPPSS ratio of less than 0.4 were assigned to the successful salvage group (group S), while the others were assigned to the failed salvage group (group F). FPSI of group F was 1.91 +/- 0.26 m/sec and of group S was 0.92 +/- 0.43 m/sec (P < 0.01). Pzf of group F was 51 +/- 3 mmHg and of group S was 51 +/- 5 mmHg (NS). Fzp of group F was -98 +/- 16 cm/sec and of group S was -46 +/- 4 cm/sec (P < 0.05). FPSI and the new index of Fzp were useful in estimating the extent of myocardial salvage. Our results suggest that the Pzf index could not differentiate between the two groups.

  3. Localization of viable, ischemic myocardium by positron-emission tomography with 11C-palmitate

    International Nuclear Information System (INIS)

    Lerch, R.A.; Ambos, H.D.; Bergmann, S.R.; Welch, M.J.; Ter-Pogossian, M.M.; Sobel, B.E.

    1981-01-01

    A study was performed to determine whether viable, but ischemic, tissue could be detected and localized in vivo based on external detection of impaired fatty acid metabolism. Accordingly, regional clearance of 11 C-palmitate was assessed by sequential PET in 15 anesthetized dogs. Clearance was consistently monoexponential from 5-15 minutes after administration of the tracer. In the absence of coronary stenosis (n = 7), clearance was homogeneous throughout the heart, with an average rate constant (k) of -0.060 +/- 0.005 min -1 (+/- SEM) and a coefficient of variation (CV) of 11.1 +/- 2.1% in each heart. Homogeneity persisted when the heart rate was increased from 84.4 +/- 6.0 to 202.7 +/- 11.5 beats/min with atropine (CV 13.2 +/- 3.5%). With left circumflex coronary stenosis (less than or equal to70% reduction in vessel diameter), homogeneity of 11 C-clearance under control conditions and with tachycardia did not differ from clearance in hearts without coronary stenosis. However, with stenosis >70% sufficient to induce ischemia without gross infarction, regional clearance of 11 C became markedly heterogeneous under control conditions (CV 28.1 +/- 5.5%, p 11 C in regions supplied by the stenotic vessel (k = -0.044 +/- 0.011 min -1 ) compared with clearance in well perfused regions (k = -0.064 +/- 0.011 min -1 , p 11 C-palmitate delineates zones of viable, ischemic myocardium that characteristically exhibit impaired oxidation of extracted fatty acid

  4. Myocardial kinetics of thallium-201 after stress in normal and perfusion-reduced canine myocardium

    International Nuclear Information System (INIS)

    Okada, R.D.

    1985-01-01

    Despite the emerging use of quantitative computer programs for assessing myocardial thallium uptake and clearance after exercise, little is known about the kinetics of thallium after exercise stress. Accordingly, 11 mongrel dogs with experimental left anterior descending coronary stenoses were given thallium during norepinephrine infusion to simulate exercise. The infusion was discontinued and thallium activity was monitored regionally using miniature radiation detectors for 3 hours. Heart rate, arterial pressure and double product all increased significantly during norepinephrine infusion. The mean fractional myocardial thallium clearance was lower (0.47 +/- 0.03 [+/- standard error of the mean]) for the stenosis zone than for the no-stenosis zone (0.57 +/- 0.03) (p less than 0.0001). The stress blood flow ratio (stenosis/no-stenosis zone = 0.27 +/- 0.06) was significantly lower than the final thallium activity ratio (0.68 +/- 0.07) (p less than 0.001), consistent with thallium redistribution occurring over the 3-hour period. Myocardial thallium activity in the stenosis zone peaked in a mean of 2.2 minutes, then washed out biexponentially with a final decay constant of 0.0035 +/- 0.0005 min-1. Myocardial thallium activity in the no-stenosis zone peaked within 1 minute in all dogs, then washed out biexponentially, with a final decay constant of 0.0043 +/- 0.0003 (p less than 0.001 compared with stenosis zone). In conclusion, fractional clearance of thallium can differentiate myocardium distal to a coronary artery stenosis from that supplied by a normal coronary vessel

  5. Connexin43 orthologues in vertebrates: phylogeny from fish to man

    NARCIS (Netherlands)

    van der Heyden, Marcel A. G.; van Eijk, Marleen; Wilders, Ronald; de Bakker, Jacques M. T.; Opthof, Tobias

    2004-01-01

    The gap junction protein connexin43 (Cx43) is widely expressed in all vertebrate species; however, in ventricular myocardium, Cx43 expression is restricted to mammalian species only, where it provides the molecular correlate for both electrical conduction and synchronization of the repolarization

  6. The effect of space microgravity on the physiological activity of mammalian resident cardiac stem cells

    Science.gov (United States)

    Belostotskaya, Galina; Zakharov, Eugeny

    Prolonged exposure to weightlessness during space flights is known to cause depression of heart function in mammals. The decrease in heart weight and its remodeling under the influence of prolonged weightlessness (or space microgravity) is assumed to be due to both morphological changes of working cardiomyocytes and their progressive loss, as well as to possible depletion of resident cardiac stem cells (CSCs) population, or their inability to self-renewal and regeneration of muscle tissue under conditions of weightlessness. We have previously shown that the presence of different maturity clones formed by resident CSCs not only in culture but also in the mammalian myocardium can be used as an indicator of the regenerative activity of myocardial cells [Belostotskaya, et al., 2013: 2014]. In this study, we were interested to investigate whether the 30-day near-Earth space flight on the spacecraft BION-M1 affects the regenerative potential of resident CSCs. Immediately after landing of the spacecraft, we had examined the presence of resident c-kit+, Sca-1+ and Isl1+ CSCs and their development in suspension of freshly isolated myocardial cells of C57BL mice in comparison to controls. Cardiac cell suspension was obtained by enzymatic digestion of the heart [Belostotskaya and Golovanova, 2014]. Immunocytochemically stained preparations of fixed cells were analyzed with confocal microscope Leica TCS SP5 (Germany) in the Resource Center of St-Petersburg State University. CSCs were labeled with appropriate antibodies. CSCs differentiation into mature cardiomyocytes was verified using antibodies to Sarcomeric α-Actinin and Cardiac Troponin T. Antibodies to Connexin43 were used to detect cell-cell contacts. All antibodies were conjugated with Alexa fluorochromes (488, 532, 546, 568, 594 and/or 647 nm), according to Zenon-technology (Invitrogen). It has been shown that, under identical conditions of cell isolation, more complete digestion of heart muscle was observed in

  7. Mesozoic mammals from Arizona: new evidence on Mammalian evolution.

    Science.gov (United States)

    Jenkins, F A; Crompton, A W; Downs, W R

    1983-12-16

    Knowledge of early mammalian evolution has been based on Old World Late Triassic-Early Jurassic faunas. The discovery of mammalian fossils of approximately equivalent age in the Kayenta Formation of northeastern Arizona gives evidence of greater diversity than known previously. A new taxon documents the development of an angular region of the jaw as a neomorphic process, and represents an intermediate stage in the origin of mammalian jaw musculature.

  8. Synthetic RNA Controllers for Programming Mammalian Cell Fate and Function

    Science.gov (United States)

    2015-11-04

    Final report for “Synthetic RNA controllers for programming mammalian cell fate and function” Principal Investigator: Christina D. Smolke...SUBTITLE Synthetic RNA controllers for programming mammalian cell fate and function 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER...Form 298 (Rev. 8-98) Prescribed by ANSI Std Z39-18   2 Synthetic RNA controllers for programming mammalian cell fate and function Task 1

  9. Ecology and evolution of mammalian biodiversity.

    Science.gov (United States)

    Jones, Kate E; Safi, Kamran

    2011-09-12

    Mammals have incredible biological diversity, showing extreme flexibility in eco-morphology, physiology, life history and behaviour across their evolutionary history. Undoubtedly, mammals play an important role in ecosystems by providing essential services such as regulating insect populations, seed dispersal and pollination and act as indicators of general ecosystem health. However, the macroecological and macroevolutionary processes underpinning past and present biodiversity patterns are only beginning to be explored on a global scale. It is also particularly important, in the face of the global extinction crisis, to understand these processes in order to be able to use this knowledge to prevent future biodiversity loss and loss of ecosystem services. Unfortunately, efforts to understand mammalian biodiversity have been hampered by a lack of data. New data compilations on current species' distributions, ecologies and evolutionary histories now allow an integrated approach to understand this biodiversity. We review and synthesize these new studies, exploring the past and present ecology and evolution of mammalian biodiversity, and use these findings to speculate about the mammals of our future.

  10. The mammalian ovary from genesis to revelation.

    Science.gov (United States)

    Edson, Mark A; Nagaraja, Ankur K; Matzuk, Martin M

    2009-10-01

    Two major functions of the mammalian ovary are the production of germ cells (oocytes), which allow continuation of the species, and the generation of bioactive molecules, primarily steroids (mainly estrogens and progestins) and peptide growth factors, which are critical for ovarian function, regulation of the hypothalamic-pituitary-ovarian axis, and development of secondary sex characteristics. The female germline is created during embryogenesis when the precursors of primordial germ cells differentiate from somatic lineages of the embryo and take a unique route to reach the urogenital ridge. This undifferentiated gonad will differentiate along a female pathway, and the newly formed oocytes will proliferate and subsequently enter meiosis. At this point, the oocyte has two alternative fates: die, a common destiny of millions of oocytes, or be fertilized, a fate of at most approximately 100 oocytes, depending on the species. At every step from germline development and ovary formation to oogenesis and ovarian development and differentiation, there are coordinated interactions of hundreds of proteins and small RNAs. These studies have helped reproductive biologists to understand not only the normal functioning of the ovary but also the pathophysiology and genetics of diseases such as infertility and ovarian cancer. Over the last two decades, parallel progress has been made in the assisted reproductive technology clinic including better hormonal preparations, prenatal genetic testing, and optimal oocyte and embryo analysis and cryopreservation. Clearly, we have learned much about the mammalian ovary and manipulating its most important cargo, the oocyte, since the birth of Louise Brown over 30 yr ago.

  11. Ecology and evolution of mammalian biodiversity

    Science.gov (United States)

    Jones, Kate E.; Safi, Kamran

    2011-01-01

    Mammals have incredible biological diversity, showing extreme flexibility in eco-morphology, physiology, life history and behaviour across their evolutionary history. Undoubtedly, mammals play an important role in ecosystems by providing essential services such as regulating insect populations, seed dispersal and pollination and act as indicators of general ecosystem health. However, the macroecological and macroevolutionary processes underpinning past and present biodiversity patterns are only beginning to be explored on a global scale. It is also particularly important, in the face of the global extinction crisis, to understand these processes in order to be able to use this knowledge to prevent future biodiversity loss and loss of ecosystem services. Unfortunately, efforts to understand mammalian biodiversity have been hampered by a lack of data. New data compilations on current species' distributions, ecologies and evolutionary histories now allow an integrated approach to understand this biodiversity. We review and synthesize these new studies, exploring the past and present ecology and evolution of mammalian biodiversity, and use these findings to speculate about the mammals of our future. PMID:21807728

  12. Focusing on RISC assembly in mammalian cells.

    Science.gov (United States)

    Hong, Junmei; Wei, Na; Chalk, Alistair; Wang, Jue; Song, Yutong; Yi, Fan; Qiao, Ren-Ping; Sonnhammer, Erik L L; Wahlestedt, Claes; Liang, Zicai; Du, Quan

    2008-04-11

    RISC (RNA-induced silencing complex) is a central protein complex in RNAi, into which a siRNA strand is assembled to become effective in gene silencing. By using an in vitro RNAi reaction based on Drosophila embryo extract, an asymmetric model was recently proposed for RISC assembly of siRNA strands, suggesting that the strand that is more loosely paired at its 5' end is selectively assembled into RISC and results in target gene silencing. However, in the present study, we were unable to establish such a correlation in cell-based RNAi assays, as well as in large-scale RNAi data analyses. This suggests that the thermodynamic stability of siRNA is not a major determinant of gene silencing in mammalian cells. Further studies on fork siRNAs showed that mismatch at the 5' end of the siRNA sense strand decreased RISC assembly of the antisense strand, but surprisingly did not increase RISC assembly of the sense strand. More interestingly, measurements of melting temperature showed that the terminal stability of fork siRNAs correlated with the positions of the mismatches, but not gene silencing efficacy. In summary, our data demonstrate that there is no definite correlation between siRNA stability and gene silencing in mammalian cells, which suggests that instead of thermodynamic stability, other features of the siRNA duplex contribute to RISC assembly in RNAi.

  13. Focusing on RISC assembly in mammalian cells

    International Nuclear Information System (INIS)

    Hong Junmei; Wei Na; Chalk, Alistair; Wang Jue; Song, Yutong; Yi Fan; Qiao Renping; Sonnhammer, Erik L.L.; Wahlestedt, Claes; Liang Zicai; Du, Quan

    2008-01-01

    RISC (RNA-induced silencing complex) is a central protein complex in RNAi, into which a siRNA strand is assembled to become effective in gene silencing. By using an in vitro RNAi reaction based on Drosophila embryo extract, an asymmetric model was recently proposed for RISC assembly of siRNA strands, suggesting that the strand that is more loosely paired at its 5' end is selectively assembled into RISC and results in target gene silencing. However, in the present study, we were unable to establish such a correlation in cell-based RNAi assays, as well as in large-scale RNAi data analyses. This suggests that the thermodynamic stability of siRNA is not a major determinant of gene silencing in mammalian cells. Further studies on fork siRNAs showed that mismatch at the 5' end of the siRNA sense strand decreased RISC assembly of the antisense strand, but surprisingly did not increase RISC assembly of the sense strand. More interestingly, measurements of melting temperature showed that the terminal stability of fork siRNAs correlated with the positions of the mismatches, but not gene silencing efficacy. In summary, our data demonstrate that there is no definite correlation between siRNA stability and gene silencing in mammalian cells, which suggests that instead of thermodynamic stability, other features of the siRNA duplex contribute to RISC assembly in RNAi

  14. Specificity of chicken and mammalian transferrins in myogenesis

    International Nuclear Information System (INIS)

    Beach, R.L.; Popiela, Heinz; Festoff, B.W.

    1985-01-01

    Chicken transferrins isolated from eggs, embryo extract, serum or ischiatic-peroneal nerves are able to stimulate incorporation of ( 3 H)thymidine, and promote myogenesis by primary chicken muscles cells in vitro. Mammalian transferrins (bovine, rat, mouse, horse, rabbit, and human) do not promote ( 3 H)thymidine incorporation or myotube development. Comparison of the peptide fragments obtained after chemical or limited proteolytic cleavage demonstrates that the four chicken transferrins are all indistinguishable, but they differ considerably from the mammalian transferrins. The structural differences between chicken and mammalian transferrins probably account for the inability of mammalian transferrins to act as mitogens for, and to support myogenesis of, primary chicken muscle cells. (author)

  15. Mammalian target of rapamycin is essential for cardiomyocyte survival and heart development in mice

    International Nuclear Information System (INIS)

    Zhang, Pengpeng; Shan, Tizhong; Liang, Xinrong; Deng, Changyan; Kuang, Shihuan

    2014-01-01

    Highlights: • mTOR is a critical regulator of many biological processes yet its function in heart is not well understood. • MCK-Cre/Mtor flox/flox mice were established to delete Mtor in cardiomyocytes. • The mTOR-mKO mice developed normally but die prematurely within 5 weeks after birth due to heart disease. • The mTOR-mKO mice had dilated myocardium and increased cell death. • mTOR-mKO hearts had reduced expression of metabolic genes and activation of mTOR target proteins. - Abstract: Mammalian target of rapamycin (mTOR) is a critical regulator of protein synthesis, cell proliferation and energy metabolism. As constitutive knockout of Mtor leads to embryonic lethality, the in vivo function of mTOR in perinatal development and postnatal growth of heart is not well defined. In this study, we established a muscle-specific mTOR conditional knockout mouse model (mTOR-mKO) by crossing MCK-Cre and Mtor flox/flox mice. Although the mTOR-mKO mice survived embryonic and perinatal development, they exhibited severe postnatal growth retardation, cardiac muscle pathology and premature death. At the cellular level, the cardiac muscle of mTOR-mKO mice had fewer cardiomyocytes due to apoptosis and necrosis, leading to dilated cardiomyopathy. At the molecular level, the cardiac muscle of mTOR-mKO mice expressed lower levels of fatty acid oxidation and glycolysis related genes compared to the WT littermates. In addition, the mTOR-mKO cardiac muscle had reduced Myh6 but elevated Myh7 expression, indicating cardiac muscle degeneration. Furthermore, deletion of Mtor dramatically decreased the phosphorylation of S6 and AKT, two key targets downstream of mTORC1 and mTORC2 mediating the normal function of mTOR. These results demonstrate that mTOR is essential for cardiomyocyte survival and cardiac muscle function

  16. Rigor mortis at the myocardium investigated by post-mortem magnetic resonance imaging.

    Science.gov (United States)

    Bonzon, Jérôme; Schön, Corinna A; Schwendener, Nicole; Zech, Wolf-Dieter; Kara, Levent; Persson, Anders; Jackowski, Christian

    2015-12-01

    Post-mortem cardiac MR exams present with different contraction appearances of the left ventricle in cardiac short axis images. It was hypothesized that the grade of post-mortem contraction may be related to the post-mortem interval (PMI) or cause of death and a phenomenon caused by internal rigor mortis that may give further insights in the circumstances of death. The cardiac contraction grade was investigated in 71 post-mortem cardiac MR exams (mean age at death 52 y, range 12-89 y; 48 males, 23 females). In cardiac short axis images the left ventricular lumen volume as well as the left ventricular myocardial volume were assessed by manual segmentation. The quotient of both (LVQ) represents the grade of myocardial contraction. LVQ was correlated to the PMI, sex, age, cardiac weight, body mass and height, cause of death and pericardial tamponade when present. In cardiac causes of death a separate correlation was investigated for acute myocardial infarction cases and arrhythmic deaths. LVQ values ranged from 1.99 (maximum dilatation) to 42.91 (maximum contraction) with a mean of 15.13. LVQ decreased slightly with increasing PMI, however without significant correlation. Pericardial tamponade positively correlated with higher LVQ values. Variables such as sex, age, body mass and height, cardiac weight and cause of death did not correlate with LVQ values. There was no difference in LVQ values for myocardial infarction without tamponade and arrhythmic deaths. Based on the observation in our investigated cases, the phenomenon of post-mortem myocardial contraction cannot be explained by the influence of the investigated variables, except for pericardial tamponade cases. Further research addressing post-mortem myocardial contraction has to focus on other, less obvious factors, which may influence the early post-mortem phase too. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  17. Right ventricular hydatid cyst ruptured to pericardium

    Directory of Open Access Journals (Sweden)

    Feridoun Sabzi

    2015-01-01

    Full Text Available Cardiac hydatidosis is rare presentation of body hydatidosis. Incidence of cardiac involvements range from 5% to 5% of patients with hydatid disease. Most common site of hydatid cyst in heart is interventricular septum and left ventricular free wall. Right ventricular free wall involvement by cyst that ruptured to pericardial cavity is very rare presentation of hydatid cyst. Cardiac involvement may have serious consequences such as rupture to blood steam or pericardial cavity. Both the disease and its surgical treatment carry a high complication rate, including rupture leading to cardiac tamponade, anaphylaxis and also death. In the present report, a 43-year-old man with constrictive pericarditis secondary to a pericardial hydatid cyst is described.

  18. [Ventricular tachyarrhythmias in patients with cardiomyopathy

    DEFF Research Database (Denmark)

    Henningsen, K.; Christensen, A.H.; Svendsen, Jesper Hastrup

    2008-01-01

    by disease, gender, age, previous cardiac arrest and treatment with implantable cardioverter-defibrillator (ICD). RESULTS: 993 patients were screened and 128 patients with cardiomyopathy were identified, corresponding to 13% of the screened patients. 58 (45%) of the patients had dilated cardiomyopathy (DCM......), 57 (45%) patients had arrhythmogenic right ventricular cardiomyopathy (ARVC) and 13 (10%) had hypertrophic cardiomyopathy (HCM). The average age was 44 years for HCM, 41 years for ARVC and 58 years for DCM. The majority of the patients were male. ICD treatment was used in 95% of the patients...... with ARVC, 70% of the patients with HCM and 59% of the patients with DCM. Only 5 patients had previous cardiac arrest without reversible cause. CONCLUSION: The study shows that cardiomyopathies are relatively frequent causes of ventricular tachyarrhythmias in patients discharged from a specialised...

  19. Detection of left ventricular thrombi by computerised tomography

    International Nuclear Information System (INIS)

    Nair, C.K.; Sketch, M.H.; Mahoney, P.D.; Lynch, J.D.; Mooss, A.N.; Kenney, N.P.

    1981-01-01

    Sixteen patients suspected of having left ventricular mural thrombi were studied. All had suffered transmural myocardial infarction. Fifteen patients had a ventricular aneurysm. One had had systemic emboli. The mean length of time between the myocardial infarction and the study was 14.8 months, with a range of one month to 79 months. All patients underwent computerised tomography of the heart, M-mode echocardiography (M-mode), and two-dimensional echocardiography (2-D). Eight patients underwent left ventricular cineangiography. Five patients had surgical confirmation. Computerised tomography, two-dimensional, and M-mode echocardiography predicted left ventricular mural thrombi in 10, eight, and one of the 16 patients, respectively. Left ventricular cineangiography predicted left ventricular mural thrombi in four out of eight patients. Computerised tomography and left ventricular cineangiography correctly predicted the presence or absence of left ventricular thrombi in all five patients who underwent operation. In the same group, however, two-dimensional and M-mode echocardiography failed to predict the presence of thrombi in one and three patients, respectively. Among the 11 patients without surgical confirmation, one, in whom no left ventricular thrombi were shown by M-mode and two-dimensional echocardiography, was found to have thrombi on computerised tomography. In another, two-dimensional echocardiography was positive but this finding was not confirmed either by computerised tomography or by left ventricular angiography. (author)

  20. Amiodarone for the treatment and prevention of ventricular fibrillation and ventricular tachycardia

    Directory of Open Access Journals (Sweden)

    Hugo Van Herendael

    2010-06-01

    Full Text Available Hugo Van Herendael, Paul DorianDivision of Cardiology, St. Michael’s Hospital, University of Toronto, Toronto, CanadaAbstract: Amiodarone has emerged as the leading antiarrhythmic therapy for termination and prevention of ventricular arrhythmia in different clinical settings because of its proven efficacy and safety. In patients with shock refractory out-of-hospital cardiac arrest and hemodynamically destabilizing ventricular arrhythmia, amiodarone is the most effective drug available to assist in resuscitation. Although the superiority of the transvenous implantable cardioverter defibrillator (ICD over amiodarone has been well established in the preventive treatment of patients at high risk of life-threatening ventricular arrhythmias, amiodarone (if used with a beta-blocker is the most effective antiarrhythmic drug to prevent ICD shocks and treat electrical storm. Both the pharmacokinetics and the electrophysiologic profile of amiodarone are complex, and its optimal and safe use requires careful patient surveillance with respect to potential adverse effects.Keywords: amiodarone, ventricular fibrillation, unstable ventricular tachycardia

  1. Left Ventricular Myocardial Function in Children With Pulmonary Hypertension: Relation to Right Ventricular Performance and Hemodynamics.

    Science.gov (United States)

    Burkett, Dale A; Slorach, Cameron; Patel, Sonali S; Redington, Andrew N; Ivy, D Dunbar; Mertens, Luc; Younoszai, Adel K; Friedberg, Mark K

    2015-08-01

    Through ventricular interdependence, pulmonary hypertension (PH) induces left ventricular (LV) dysfunction. We hypothesized that LV strain/strain rate, surrogate measures of myocardial contractility, are reduced in pediatric PH and relate to invasive hemodynamics, right ventricular strain, and functional measures of PH. At 2 institutions, echocardiography was prospectively performed in 54 pediatric PH patients during cardiac catheterization, and in 54 matched controls. Patients with PH had reduced LV global longitudinal strain (LS; -18.8 [-17.3 to -20.4]% versus -20.2 [-19.0 to -20.9]%; P=0.0046) predominantly because of reduced basal (-12.9 [-10.8 to -16.3]% versus -17.9 [-14.5 to -20.7]%; Pright ventricular free-wall LS (r=0.64; PBrain natriuretic peptide levels correlated moderately with septal LS (r=0.48; P=0.0038). PH functional class correlated moderately with LV free-wall LS (r=-0.48; P=0.0051). The septum, shared between ventricles and affected by septal shift, was the most affected LV region in PH. Pediatric PH patients demonstrate reduced LV strain/strain rate, predominantly within the septum, with relationships to invasive hemodynamics, right ventricular strain, and functional PH measures. © 2015 American Heart Association, Inc.

  2. Assessment of left ventricular global function

    International Nuclear Information System (INIS)

    Breuel, H.-P.; Baehre, M.

    1985-01-01

    Radionuclide ventriculography (RNV), i.e. noninvasive evaluation of left venticular performance following the application of radionuclides has had a major impact on many aspects of cardiology and has proven its clinical value and reliability in the last few years. This article deals mainly with the changes in global left ventricular function. The clinical applications of RNV for coronary artery diseases and valvular heart diseases are described. (Auth.)

  3. Left ventricular heart failure and pulmonary hypertension†

    Science.gov (United States)

    Rosenkranz, Stephan; Gibbs, J. Simon R.; Wachter, Rolf; De Marco, Teresa; Vonk-Noordegraaf, Anton; Vachiéry, Jean-Luc

    2016-01-01

    Abstract In patients with left ventricular heart failure (HF), the development of pulmonary hypertension (PH) and right ventricular (RV) dysfunction are frequent and have important impact on disease progression, morbidity, and mortality, and therefore warrant clinical attention. Pulmonary hypertension related to left heart disease (LHD) by far represents the most common form of PH, accounting for 65–80% of cases. The proper distinction between pulmonary arterial hypertension and PH-LHD may be challenging, yet it has direct therapeutic consequences. Despite recent advances in the pathophysiological understanding and clinical assessment, and adjustments in the haemodynamic definitions and classification of PH-LHD, the haemodynamic interrelations in combined post- and pre-capillary PH are complex, definitions and prognostic significance of haemodynamic variables characterizing the degree of pre-capillary PH in LHD remain suboptimal, and there are currently no evidence-based recommendations for the management of PH-LHD. Here, we highlight the prevalence and significance of PH and RV dysfunction in patients with both HF with reduced ejection fraction (HFrEF) and HF with preserved ejection fraction (HFpEF), and provide insights into the complex pathophysiology of cardiopulmonary interaction in LHD, which may lead to the evolution from a ‘left ventricular phenotype’ to a ‘right ventricular phenotype’ across the natural history of HF. Furthermore, we propose to better define the individual phenotype of PH by integrating the clinical context, non-invasive assessment, and invasive haemodynamic variables in a structured diagnostic work-up. Finally, we challenge current definitions and diagnostic short falls, and discuss gaps in evidence, therapeutic options and the necessity for future developments in this context. PMID:26508169

  4. Ventricular enlargement in patients with affective disorders

    International Nuclear Information System (INIS)

    Murashita, Jun; Kato, Tadafumi; Shioiri, Toshiki; Hamakawa, Inubushi, Toshiro; Hiroshi; Takahashi, Saburo

    1994-01-01

    Ventricular enlargement was determined using linear measurement