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Sample records for pig pathophysiological ventricular

  1. Verapamil reduces incidence of reentry during ventricular fibrillation in pigs.

    Science.gov (United States)

    Jin, Qi; Dosdall, Derek J; Li, Li; Rogers, Jack M; Ideker, Raymond E; Huang, Jian

    2014-11-01

    The characteristics of reentrant circuits during short duration ventricular fibrillation (SDVF; 20 s in duration) and the role of Ca(++) and rapid-activating delayed rectifier potassium currents during long duration ventricular fibrillation (LDVF; up to 10 min in duration) were investigated using verapamil and sotalol. Activation mapping of the LV epicardium with a 21 × 24 electrode plaque was performed in 12 open-chest pigs. Pigs were given either verapamil (0.136 mg/kg) or sotalol (1.5 mg/kg) and verapamil. Reentry patterns were quantified for SDVF, and, for LDVF, activation patterns were compared with our previously reported control LDVF data. Verapamil significantly increased conduction velocity around the reentrant core by 10% and reduced the reentrant cycle length by 15%, with a net reduction in reentry incidence of 70%. Sotolol had an opposite effect of decreasing the conduction velocity around the core by 6% but increasing the reentrant cycle length by 13%, with a net reduction of reentry incidence of 50%. After 200 s of VF, verapamil significantly slowed wavefront conduction velocity and activation rate compared with control data. Verapamil decreased the incidence of reentry in SDVF by accelerating conduction velocity to increase the likelihood of conduction block, possibly through increased sympathetic tone. The drug slowed activation rate and conduction velocity after 200 s of VF, suggesting that L-type Ca(++) channels remain active and may be important in the maintenance of LDVF. Sotalol in addition to verapamil caused no additional antiarrhythmic effect.

  2. A pig model of acute right ventricular afterload increase by hypoxic pulmonary vasoconstriction.

    Science.gov (United States)

    Knai, Kathrine; Skjaervold, Nils Kristian

    2017-01-03

    The aim of this study was to construct a non-invasive model for acute right ventricular afterload increase by hypoxic pulmonary vasoconstriction. Intact animal models are vital to improving our understanding of the pathophysiology of acute right ventricular failure. Acute right ventricular failure is caused by increased afterload of the right ventricle by chronic or acute pulmonary hypertension combined with regionally or globally reduced right ventricular contractile capacity. Previous models are hampered by their invasiveness; this is unfortunate as the pulmonary circulation is a low-pressure system that needs to be studied in closed chest animals. Hypoxic pulmonary vasoconstriction is a mechanism that causes vasoconstriction in alveolar vessels in response to alveolar hypoxia. In this study we explored the use of hypoxic pulmonary vasoconstriction as a means to increase the pressure load on the right ventricle. Pulmonary hypertension was induced by lowering the FiO2 to levels below the physiological range in eight anesthetized and mechanically ventilated pigs. The pigs were monitored with blood pressure measurements and blood gases. The mean pulmonary artery pressures (mPAP) of the animals increased from 18.3 (4.2) to 28.4 (4.6) mmHg and the pulmonary vascular resistance (PVR) from 254 (76) dyns/cm(5) to 504 (191) dyns/cm(5), with a lowering of FiO2 from 0.30 to 0.15 (0.024). The animals' individual baseline mPAPs varied substantially as did their response to hypoxia. The reduced FiO2 level yielded an overall lowering in oxygen offer, but the global oxygen consumption was unaltered. We showed in this study that the mPAP and the PVR could be raised by approximately 100% in the study animals by lowering the FiO2 from 0.30 to 0.15 (0.024). We therefore present a novel method for minimally invasive (closed chest) right ventricular afterload manipulations intended for future studies of acute right ventricular failure. The method should in theory be reversible

  3. Advancing knowledge of right ventricular pathophysiology in chronic pressure overload: Insights from experimental studies.

    Science.gov (United States)

    Guihaire, Julien; Noly, Pierre Emmanuel; Schrepfer, Sonja; Mercier, Olaf

    2015-10-01

    The right ventricle (RV) has to face major changes in loading conditions due to cardiovascular diseases and pulmonary vascular disorders. Clinical experience supports evidence that the RV better compensates for volume than for pressure overload, and for chronic than for acute changes. For a long time, right ventricular (RV) pathophysiology has been restricted to patterns extrapolated from left heart studies. However, the two ventricles are anatomically, haemodynamically and functionally distinct. RV metabolic properties may also result in a different behaviour in response to pathological conditions compared with the left ventricle. In this review, current knowledge of RV pathophysiology is reported in the setting of chronic pressure overload, including recent experimental findings and emerging concepts. After a time-varying compensated period with preserved cardiac output despite overload conditions, RV failure finally occurs, leading to death. The underlying mechanisms involved in the transition from compensatory hypertrophy to maladaptive remodelling are not completely understood. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  4. La3+ Transmembrane Research in Guinea Pig Ventricular Cells by Fura-2 Fluorescence

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Binding of La3+ to Fura-2 can change 340/380 nm fluorescence intensity ratio. Whether La3+ cross ventricular cell membrane was detected by this fluorescent probe technique. Fura-2 loaded isolated guinea pig ventricular cells were exposed to 0.01-0.1mM extracellular Lanthanum ion concentration, 340nm/380 nm fluorescence ratio was not changed. Using calcium channel agonist BAY K8644, KCL (35mM) depolarization to open the voltage-dependent calcium channel (VDCC); Adrenoceptor agonist to excite adrenoceptor, 340/380 ratio was not changed, suggesting that La3+can not enter guinea pig ventricular cells in this case.

  5. Pathology and Pathophysiology of Inhalational Anthrax in a Guinea Pig Model

    Science.gov (United States)

    Savransky, Vladimir; Sanford, Daniel C.; Syar, Emily; Austin, Jamie L.; Tordoff, Kevin P.; Anderson, Michael S.; Stark, Gregory V.; Barnewall, Roy E.; Briscoe, Crystal M.; Lemiale-Biérinx, Laurence; Park, Sukjoon; Ionin, Boris

    2013-01-01

    Nonhuman primates (NHPs) and rabbits are the animal models most commonly used to evaluate the efficacy of medical countermeasures against anthrax in support of licensure under the FDA's “Animal Rule.” However, a need for an alternative animal model may arise in certain cases. The development of such an alternative model requires a thorough understanding of the course and manifestation of experimental anthrax disease induced under controlled conditions in the proposed animal species. The guinea pig, which has been used extensively for anthrax pathogenesis studies and anthrax vaccine potency testing, is a good candidate for such an alternative model. This study was aimed at determining the median lethal dose (LD50) of the Bacillus anthracis Ames strain in guinea pigs and investigating the natural history, pathophysiology, and pathology of inhalational anthrax in this animal model following nose-only aerosol exposure. The inhaled LD50 of aerosolized Ames strain spores in guinea pigs was determined to be 5.0 × 104 spores. Aerosol challenge of guinea pigs resulted in inhalational anthrax with death occurring between 46 and 71 h postchallenge. The first clinical signs appeared as early as 36 h postchallenge. Cardiovascular function declined starting at 20 h postexposure. Hematogenous dissemination of bacteria was observed microscopically in multiple organs and tissues as early as 24 h postchallenge. Other histopathologic findings typical of disseminated anthrax included suppurative (heterophilic) inflammation, edema, fibrin, necrosis, and/or hemorrhage in the spleen, lungs, and regional lymph nodes and lymphocyte depletion and/or lymphocytolysis in the spleen and lymph nodes. This study demonstrated that the course of inhalational anthrax disease and the resulting pathology in guinea pigs are similar to those seen in rabbits and NHPs, as well as in humans. PMID:23357384

  6. Pulmonary hypertension and right heart failure in heart failure with preserved left ventricular ejection fraction: pathophysiology and natural history.

    Science.gov (United States)

    Segers, Vincent F M; Brutsaert, Dirk L; De Keulenaer, Gilles W

    2012-05-01

    Pulmonary hypertension and right heart failure are common findings in patients suffering from heart failure with preserved ejection fraction (HFpEF). In this review, we summarize our current understanding of the pathophysiology of pulmonary hypertension related to heart failure. HFpEF is a clinical syndrome with increasing prevalence and a mortality rate similar to heart failure with reduced ejection fraction. Because the pathophysiology and even the definition of this disease are still controversial, we will first outline the current conceptual framework around heart failure with preserved ejection fraction. Next, we will outline our current knowledge on the pathophysiology of pulmonary hypertension related to left ventricular failure and diastolic dysfunction. Diastolic dysfunction induces pulmonary hypertension through passive transmission of elevated end diastolic pressures, reactive pulmonary vasoconstriction, and vascular remodeling. Eventually, right ventricular failure develops that can further potentiate left ventricular failure because of their close mechanical, cellular, and biochemical integration. Exciting new studies have led to an increased understanding of the underlying pathophysiology and indicate that pulmonary hypertension in heart failure may be treatable.

  7. The pathophysiologic aspects and clinical implications of electrocardiographic parameters of ventricular conduction delay in repaired tetralogy of Fallot.

    Science.gov (United States)

    Udink ten Cate, Floris E A; Sreeram, Narayanswami; Brockmeier, Konrad

    2014-01-01

    The 12-lead surface electrocardiogram is a valuable and feasible clinical tool in the management of patients following tetralogy of Fallot (TOF) repair. The importance of QRS duration in TOF patients has long been acknowledged. A prolonged QRS complex has been associated with increased risk for subsequent life-threatening ventricular arrhythmia and sudden cardiac death. Our current ability to risk-stratify TOF patients for malignant arrhythmogenic events primarily on the basis of QRS duration is rather limited. Nevertheless, increasing evidence suggests that QRS morphology and duration may be useful as surrogate markers of infundibular and regional right ventricular myocardial disease. The aim of this review is to provide a critical appraisal of the clinical implications of established and new electrocardiographic markers of ventricular conduction delay in TOF patients following surgical correction with a particular focus on QRS duration, lengthening, and fragmentation. In addition, the pathophysiological background of these parameters is addressed.

  8. Flecainide attenuates rate adaptation of ventricular repolarization in guinea-pig heart

    DEFF Research Database (Denmark)

    Osadchii, Oleg E.

    2016-01-01

    OBJECTIVES: Flecainide is class Ic antiarrhythmic agent that was found to increase the risk of sudden cardiac death. Arrhythmic responses to flecainide could be precipitated by exercise, suggesting a role played by inappropriate rate adaptation of ventricular repolarization. This study therefore...... examined flecainide effect on adaptation of the QT interval and ventricular action potential duration (APD) to abrupt reductions of the cardiac cycle length. DESIGN: ECG and ventricular epicardial and endocardial monophasic APD were recorded in isolated, perfused guinea-pig heart preparations upon...... a sustained cardiac acceleration (rapid pacing for 30 s), and following a single perturbation of the cycle length evoked by extrasystolic stimulation. RESULTS: Sustained increase in heart rate was associated with progressive bi-exponential shortening of the QT interval and APD. Flecainide prolonged...

  9. Ivabradine improves left ventricular function during chronic hypertension in conscious pigs.

    Science.gov (United States)

    Rienzo, Mario; Melka, Jonathan; Bizé, Alain; Sambin, Lucien; Jozwiak, Mathieu; Su, Jin Bo; Hittinger, Luc; Berdeaux, Alain; Ghaleh, Bijan

    2015-01-01

    During chronic hypertension, increases in heart rate (HR) or adrenergic stimulation are associated with maladaptive left ventricular responses as isovolumic contraction and relaxation durations failed to reduce, impeding filling. We, therefore, investigated the effects of acute selective HR reduction with ivabradine on left ventricular dysfunction during chronic hypertension. Accordingly, chronically instrumented pigs received angiotensin II infusion during 4 weeks to induce chronic hypertension. Left ventricular function was investigated while angiotensin II infusion was stopped. A single intravenous dose of ivabradine was administered at days 0 and 28. Dobutamine infusion was also performed. HR was increased at day 28 versus day 0. Paradoxically, both isovolumic contraction and relaxation times failed to reduce and remained unchanged (57±3 versus 58±3 ms and 74±3 versus 70±3 at day 28 versus day 0, respectively). At day 28, ivabradine significantly reduced HR by 27%. Concomitantly, abnormal ventricular responses were corrected because both isovolumic contraction and relaxation times were significantly reduced while filling time was improved. Similarly at day 28, maladaptive responses of isovolumic contraction and relaxation to dobutamine were no longer observed during HR reduction with ivabradine. Correction of HR reduction with pacing showed that non-HR-related mechanisms also participated to these beneficial effects. In this model of chronic hypertension and left ventricular hypertrophy, acute HR reduction with ivabradine corrects the maladaptive responses of cardiac cycle phases by restoring a normal profile for isovolumic contraction and relaxation both at rest and under adrenergic stimuli, ultimately favoring filling.

  10. Effects of Glucose on Transmembrane Ionic Current of Ventricular Myocytes in Guinea Pig

    Institute of Scientific and Technical Information of China (English)

    AIJing; JIAOJun-dong; WANGHe; DUZhi-min; YANGBao-feng

    2004-01-01

    Aim To determine the effects of glucose oi1APD, IK1, IK, ICa-L of ventricular myocytes in guinea pigs. Methods Whole-cell patch-clamp technique was used to record the changed action potential ionic current induced by glucose of single cell in guinea pig ventricular myocytes, to compare the action of 0, 10 and 20 mmol·L-1 glucoses on transmembrane ionic current. Results (1) Compared with 10 mmol·L-1 glucose concentrations, 0 and 20 mmol·L-1 glucose both shortened APD of ventricular myocytes (P<0.05). (2) The inward components of IK1 density were maximal when the glucose concentration was at 10 mmol·L-1. Normalized 1-V relationships showed that both 0 and 20 mmol·L-1 glucose produced a left-shift of I-V curve. The reverse potential changed from-72.4 mV to-64.6 mV. (3) Compared with 10 mmol·L-1, both 0 and 20 mmol·L-1 glucose markedly increased the ICa-L amplitude and density. The ICa-L current density was (-8.0350.82) pA/pF (n=8) at a test potential of 10 mV when the glucose concentration was 10 mmol·L-1. But its current density decreased to (-5.45±0.67) pA/pF and (-6.50±0.56) pA/pF when glucose concentrations were 0 and 20 mmol·L-1, respectively. (4) The current densities of IK were (18.96±2.86) pA/pF, (8.66±1.87) pA/pF, and(15.32:1:3.12) pA/pF, at ±70mV for 0, 10 and 20 mmol·L-1 glucoses, respectively. Conclusion Glucose in different concentrations has different effects on APD, IK1, IK, and ICa-L of single ventricular myocyte in guinea pigs. There are similar actions of 0 and 20 mmol·L-1 glucoses on the transmembrane ionic current of ventricular myocytes in guinea pigs.

  11. Effect of hydrogen peroxide on persistent sodium current in guinea pig ventricular myocytes

    Institute of Scientific and Technical Information of China (English)

    Ji-hua MA; An-tao LUO; Pei-hua ZHANG

    2005-01-01

    Aim: To study the effect of hydrogen peroxide (H2O2) on persistent sodium current (INa.P) in guinea pig ventricular myocytes.Methods: The whole-cell, cell-attached, and inside-out patch-clamp techniques were applied on isolated ventricular myocytes from guinea pig.Results: H2O2 (0.1 mmol/L, 0.5 mmol/L and 1.0mmol/L) increased the amplitude of whole-cell INa.P in a concentration-dependent mmol/L) increased persistent sodium channel activity in cell-attached and insideout patches.The mean open probability was increased from control values of 0.015±0.004 and 0.012±0.003 to 0.106±0.011 and 0.136±0.010, respectively (P<0.01 vs control).They were then decreased to 0.039±0.024 and 0.027±0.006,respectively, after the addition of 1 mmol/L GSH (P<0.01 vs H2O2).The time when open probability began to increase and reached a maximum was shorter in insideout patches than that in cell-attached patches (4.8± 1.0 min vs 11.5±3.9 min, P<0.01;9.6±1.6 min vs 18.7±4.7 min, P<0.01).Conclusion: H2O2 increased the INa.P of guinea pig ventricular myocytes in a concentration-dependent manner, possibly by directly oxidating the cell membrane.

  12. Quinidine elicits proarrhythmic changes in ventricular repolarization and refractoriness in guinea-pig.

    Science.gov (United States)

    Osadchii, Oleg E

    2013-04-01

    Quinidine is a class Ia Na(+) channel blocker that prolongs cardiac repolarization owing to the inhibition of I(Kr), the rapid component of the delayed rectifier current. Although quinidine may induce proarrhythmia, the contributing mechanisms remain incompletely understood. This study examined whether quinidine may set proarrhythmic substrate by inducing spatiotemporal abnormalities in repolarization and refractoriness. The monophasic action potential duration (APD), effective refractory periods (ERPs), and volume-conducted electrocardiograms (ECGs) were assessed in perfused guinea-pig hearts. Quinidine was found to produce the reverse rate-dependent prolongation of ventricular repolarization, which contributed to increased steepness of APD restitution. Throughout the epicardium, quinidine elicited a greater APD increase in the left ventricular chamber compared with the right ventricle, thereby enhancing spatial repolarization heterogeneities. Quinidine prolonged APD to a greater extent than ERP, thus extending the vulnerable window for ventricular re-excitation. This change was attributed to increased triangulation of epicardial action potential because of greater APD lengthening at 90% repolarization than at 30% repolarization. Over the transmural plane, quinidine evoked a greater ERP prolongation at endocardium than epicardium and increased dispersion of refractoriness. Premature ectopic beats and monomorphic ventricular tachycardia were observed in 50% of quinidine-treated heart preparations. In summary, abnormal changes in repolarization and refractoriness contribute greatly to proarrhythmic substrate upon quinidine infusion.

  13. Tetrahydroacridine inhibits voltage-dependent Na+ current in guinea-pig ventricular myocytes

    Institute of Scientific and Technical Information of China (English)

    Wei WANG; Yi-ping WANG; Guo-yuan HU

    2004-01-01

    AIM: To study the effects of tetrahydroacridine (tacrine) on voltage-gated Na+ channels in cardiac tissues.METHODS: Single ventricular myocytes were enzymatically dissociated from adult guinea-pig heart. Voltagedependent Na+ current was recorded using whole cell voltage-clamp technique. RESULTS: (1) Tacrine reversibly inhibited Na+ current with an IC50 value of 120 μmol/L (95 % confidence range: 108-133 μmol/L). (2) The inhibitory effects of tacrine on Na+ current exhibited both a tonic nature and use-dependence. (3) Tacrine at 100 μmol/L caused a negative shift (about 10 mV) in the voltage-dependence of steady-state inactivation of Na+ current, and retarded its recovery from inactivation, but did not affect its activation curve. (4) Intracellular application of tacrine significantly inhibited Na+ current. CONCLUSION: In addition to blocking other voltage-gated ion channels,tacrine blocked Na+ channels in guinea-pig ventricular myocytes. Tactine acted as inactivation stabilizer of Na+channels in cardiac tissues.

  14. Exploring energy loss by vector flow mapping in children with ventricular septal defect: Pathophysiologic significance.

    Science.gov (United States)

    Honda, Takashi; Itatani, Keiichi; Takanashi, Manabu; Kitagawa, Atsushi; Ando, Hisashi; Kimura, Sumito; Oka, Norihiko; Miyaji, Kagami; Ishii, Masahiro

    2017-10-01

    Vector flow mapping is a novel echocardiographic flow visualization method, and it has enabled us to quantitatively evaluate the energy loss in the left ventricle (intraventricular energy loss). Although intraventricular energy loss is assumed to be a part of left ventricular workload itself, it is unclear what this parameter actually represents. The aim of the present study was to elucidate the characteristics of intraventricular energy loss. We enrolled 26 consecutive children with ventricular septal defect (VSD). On echocardiography vector flow mapping, intraventricular energy loss was measured in the apical 3-chamber view. We measured peak energy loss and averaged energy loss in the diastolic and systolic phases, and subsequently compared these parameters with catheterization parameters and serum brain natrium peptide (BNP) level. Diastolic, peak, and systolic energy loss were strongly and positively correlated with right ventricular systolic pressure (r=0.76, 0.68, and 0.56, penergy loss were significantly correlated with BNP (r=0.75, 0.69 and 0.49, penergy loss in the left ventricle. The results of the present study encourage further studies in other study populations to elucidate the characteristics of intraventricular energy loss for its possible clinical application. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Effects of Erythropoietin Administration on Adrenal Glands of Landrace/Large White Pigs after Ventricular Fibrillation.

    Science.gov (United States)

    Faa, Armando; Faa, Gavino; Papalois, Apostolos; Obinu, Eleonora; Locci, Giorgia; Pais, Maria Elena; Lelovas, Pavlos; Barouxis, Dimitrios; Pantazopoulos, Charalampos; Vasileiou, Panagiotis V; Iacovidou, Nicoletta; Xanthos, Theodoros

    2016-01-01

    Aim. To evaluate the effects of erythropoietin administration on the adrenal glands in a swine model of ventricular fibrillation and resuscitation. Methods. Ventricular fibrillation was induced via pacing wire forwarded into the right ventricle in 20 female Landrace/Large White pigs, allocated into 2 groups: experimental group treated with bolus dose of erythropoietin (EPO) and control group which received normal saline. Cardiopulmonary resuscitation (CPR) was performed immediately after drug administration as per the 2010 European Resuscitation Council (ERC) guidelines for Advanced Life Support (ALS) until return of spontaneous circulation (ROSC) or death. Animals who achieved ROSC were monitored, mechanically ventilated, extubated, observed, and euthanized. At necroscopy, adrenal glands samples were formalin-fixed, paraffin-embedded, and routinely processed. Sections were stained with hematoxylin-eosin. Results. Oedema and apoptosis were the most frequent histological changes and were detected in all animals in the adrenal cortex and in the medulla. Mild and focal endothelial lesions were also detected. A marked interindividual variability in the degree of the intensity of apoptosis and oedema at cortical and medullary level was observed within groups. Comparing the two groups, higher levels of pathological changes were detected in the control group. No significant difference between the two groups was observed regarding the endothelial changes. Conclusions. In animals exposed to ventricular fibrillation, EPO treatment has protective effects on the adrenal gland.

  16. Effects of Erythropoietin Administration on Adrenal Glands of Landrace/Large White Pigs after Ventricular Fibrillation

    Directory of Open Access Journals (Sweden)

    Armando Faa

    2016-01-01

    Full Text Available Aim. To evaluate the effects of erythropoietin administration on the adrenal glands in a swine model of ventricular fibrillation and resuscitation. Methods. Ventricular fibrillation was induced via pacing wire forwarded into the right ventricle in 20 female Landrace/Large White pigs, allocated into 2 groups: experimental group treated with bolus dose of erythropoietin (EPO and control group which received normal saline. Cardiopulmonary resuscitation (CPR was performed immediately after drug administration as per the 2010 European Resuscitation Council (ERC guidelines for Advanced Life Support (ALS until return of spontaneous circulation (ROSC or death. Animals who achieved ROSC were monitored, mechanically ventilated, extubated, observed, and euthanized. At necroscopy, adrenal glands samples were formalin-fixed, paraffin-embedded, and routinely processed. Sections were stained with hematoxylin-eosin. Results. Oedema and apoptosis were the most frequent histological changes and were detected in all animals in the adrenal cortex and in the medulla. Mild and focal endothelial lesions were also detected. A marked interindividual variability in the degree of the intensity of apoptosis and oedema at cortical and medullary level was observed within groups. Comparing the two groups, higher levels of pathological changes were detected in the control group. No significant difference between the two groups was observed regarding the endothelial changes. Conclusions. In animals exposed to ventricular fibrillation, EPO treatment has protective effects on the adrenal gland.

  17. Procainamide and lidocaine produce dissimilar changes in ventricular repolarization and arrhythmogenicity in guinea-pig.

    Science.gov (United States)

    Osadchii, Oleg E

    2014-08-01

    Procainamide is class Ia Na(+) channel blocker that may prolong ventricular repolarization secondary to inhibition of IK r , the rapid component of the delayed rectifier K(+) current. In contrast to selective IN a blockers such as lidocaine, procainamide was shown to produce arrhythmogenic effects in the clinical setting. This study examined whether pro-arrhythmic responses to procainamide may be accounted for by drug-induced repolarization abnormalities including impaired electrical restitution kinetics, spatial gradients in action potential duration (APD), and activation-to-repolarization coupling. In perfused guinea-pig hearts, procainamide was found to prolong the QT interval on ECG and left ventricular (LV) epicardial monophasic APD, increased the maximum slope of electrical restitution, enhanced transepicardial APD variability, and eliminated the inverse correlation between the local APD and activation time values determined at distinct epicardial recording sites prior to drug infusion. In contrast, lidocaine had no effect on electrical restitution, the degree of transepicardial repolarization heterogeneities, and activation-to-repolarization coupling. Spontaneous episodes of monomorphic ventricular tachycardia were observed in 57% of procainamide-treated heart preparations. No arrhythmia was induced by lidocaine. In summary, this study suggests that abnormal changes in repolarization may contribute to pro-arrhythmic effects of procainamide.

  18. Ionic basis of the different action potential configurations of single guinea-pig atrial and ventricular myocytes.

    Science.gov (United States)

    Hume, J R; Uehara, A

    1985-11-01

    Single myocardial cells were enzymatically dispersed from guinea-pig atria and ventricles. At 25 degrees C, atrial cell action potentials differed significantly from ventricular cell action potentials in duration (atrial = 141 ms, ventricular = 497 ms) and over-shoot (atrial = +36 mV, ventricular = +42 mV). Action potentials of atrial and ventricular cells responded differently to changes in external K+ concentration ([K+]o). Elevation of [K+]o from 6 to 11 mM depolarized atrial cells but produced no significant change in action potential duration; similar changes in [K+]o depolarized ventricular cells and produced a significant shortening of the action potential duration. Voltage-clamp experiments were performed to investigate the ionic basis underlying the different action potential configurations of single atrial and ventricular myocytes. A single-micropipette voltage-clamp technique was used, employing either extremely small-tip diameter pipettes, without internal cell dialysis (Hume & Giles, 1983), or larger tip diameter pipettes, with internal dialysis (Hamill, Marty, Neher, Sakmann & Sigworth, 1981). Two significant differences in background K+ conductance in single atrial and ventricular myocytes were observed: (i) the isochronal (5 s) current-voltage relationship of single ventricular myocytes exhibited a region of prominent negative slope conductance and elevation of [K+]o produced cross-over; a negative slope conductance region was absent in atrial cells and elevation of [K+]o produced very little cross-over of isochronal current-voltage relationships, and (ii) hyperpolarizing voltage pulses applied from holding potentials of -50 mV elicited inward current in ventricular cells which decayed with time; similar voltage-clamp pulses in atrial cells elicited inward currents which fail to decay. Single K+ channel current measurements confirmed the existence of different resting K+ channel properties in single atrial and ventricular myocytes. Resting K

  19. Biphasic effects of haloperidol on sodium currents in guinea pig ventricular myocytes

    Institute of Scientific and Technical Information of China (English)

    Lu-feng CHENG; Dong YAN; Subat TURDI; Parhat KERRAM

    2007-01-01

    Aim: To study the effects of haloperidol on sodium currents (INa) in guinea pig ventricular myocytes. Method: Whole-cell patch clamp technique was employed to evaluate the effects of haloperidol on INa, in individual ventricular myocytes.Results: Haloperidol (0.1-3 μmol/L) inhibited INa in a concentration-dependent manner with an IC50 of 0.253±0.015 μmol/L. The inhibition rate of haloperidol (0.3 μmol/L) on INa was 22.14%±0.02%, and the maximum conductance was reduced.Haloperidol significantly reduced the midpoints for the activation and inactiva-tion of INa by 2.09 and 4.09 mV, respectively. The time constant of recovery was increased. The increase in time intervals could only recover by 90.14%±1.4% (n=6); however, haloperidol at 0.03 μmol/L enhanced INa conductance. The mid-points for the activation and inactivation of INa were shifted by 1.38 and 5.69 mV,respectively, at this concentration of haloperidol.Conclusion: Haloperidol dis-played a biphasic effect on INa in guinea pig cardiac myocytes. High concentra-tions of haloperidol inhibited INa, while lower concentrations of haloperidol shifted the activation and inactivation curve to the left. Full recovery of recovery curve was not achieved after 0.3 μmol/L haloperidol administration, indicating that the drug affects the inactivated state of sodium channels.

  20. Left ventricular mechanoenergetics under altered coronary perfusion in guinea pig hearts.

    Science.gov (United States)

    Matsushita, T; Takaki, M; Fujii, W; Matsubara, H; Suga, H

    1995-01-01

    Coronary perfusion pressure (CPP) is well known to affect left ventricular (LV) mechanoenergetics (Gregg's phenomenon). The garden hose effect via the Frank-Starling mechanism caused by coronary distension has long been considered to be the underlying mechanism of this phenomenon. However, recent studies have revealed a close correlation between CPP and the excitation-contraction coupling in myocytes. The aim of this study was to investigate the mechanoenergetic aspects of Gregg's phenomenon by the ventricular contractility (Emax) dependency of the myocardial oxygen consumption (VO2)-total mechanical energy (PVA, systolic pressure-volume area) relationship. Experiments were performed in the excised, cross-circulated guinea pig heart preparation. The protocol consisted of LV volume loading (VOL run), changing coronary perfusion pressure at a fixed LV volume (CPP run) and intracoronary calcium (Ca) infusion also at the same LV volume (Ca run). In all seven hearts, we obtained a linear VO2-PVA relation in VOL run. The VO2-PVA relations in CPP and Ca runs, which equally enhanced Emax, were highly linear and had no significant difference in their slopes, both significantly steeper than in VOL run. These findings suggest no significant difference in the oxygen cost of Emax between CPP and Ca runs. The enhanced LV mechanoenergetics under increasing CPP is characterized by increases in the VO2 component primarily for the excitation-contraction coupling to a greater degree than expected from the mechanical (garden hose) effect.

  1. Thrombosis in continuous-flow left ventricular assist devices: pathophysiology, prevention, and pharmacologic management.

    Science.gov (United States)

    Jennings, Douglas L; Weeks, Phillip A

    2015-01-01

    Continuous-flow left ventricular assist devices reduce short-term mortality and improve quality of life in patients with end-stage heart failure. Unfortunately, device-related complications remain common, with many patients experiencing adverse events within the first year. New literature suggests that rates of device-related thrombosis may be increasing since 2011, which is particularly troublesome given that this pathology can result in a disabling stroke, organ damage, and death. In 2013, a group of practitioners in the field of mechanical circulatory support published a treatment algorithm based on their expert opinion. However, a comprehensive review of the pharmacotherapy of this condition is lacking. A search of the literature revealed 20 separate publications of case reports or case series describing outcomes associated with the use of drug therapy for suspected pump thrombosis. Each of these experiences was limited by small sample size, nonrandomized treatment allocation, and nonstandardized medication dosing. Data describing the outcomes of surgical versus medical management of device thrombosis are also sparse, with only three published reports identified. Based on the review of this limited literature, surgical management appears to be the preferred treatment modality, especially in those with organ hypoperfusion or hemodynamic instability. In patients ineligible for surgery, pharmacotherapy options remain limited. Use of all drug classes described in the literature for the HeartMate II device-fibrinolytics, glycoprotein IIb/IIIa inhibitors, and direct thrombin inhibitors-was hindered by either marginal efficacy or bleeding. Based on historical experience with unfractionated heparin in patients under HeartMate II support, we recommend this agent as a possible option for those with suspected pump thrombosis in lieu of surgical device exchange. For the HeartWare HVAD, limited data suggest that direct intraventricular administration of alteplase may be an

  2. Physiological role of endogenous amines in the modulation of ventricular automaticity in the guinea-pig.

    Science.gov (United States)

    Hume, J; Katzung, B G

    1980-12-01

    1. Current-clamp experiments were carried out with guinea-pig papillary muscles to determine the dependence of depolarization-induced automaticity on endogenous catecholamines. 2. Catecholamine depletion was produced by pre-treatment of animals with 6-hydroxydopamine and confirmed by fluorimetric assay of right ventricular tissue. Papillary muscles from depleted animals demonstrated a marked suppression of depolarization-induced automaticity for maximum diastolic potentials less negative than -55 mV. This suppression was completely reversed by noradrenaline but not by tyramine. 3. In normal tissue, noradrenaline and tyramine had much smaller effects on automaticity arising from maximum diastolic potentials negative to -55 mV than on repetitive activity arising positive to this level. 4. L-propranolol in concentrations of 2-3 x 10(-7) M reduced repetitive activity in the less negative range of maximum diastolic potential. No evidence of direct membrane depression was observed at these doses and the effect was reversed by application of noradrenaline. 5. D-propranolol, the isomer with much lower beta-receptor blocking potency, required twentyfold higher concentrations to depress automaticity and this was accompanied by evidence of direct membrane depression, i.e. reduction of upstroke velocity of action potentials. 6. These results show that automaticity induced in guinea-pig papillary muscles by depolarization positive to -55 mV is strongly dependent upon endogenous catecholamines. 7. The hypothesis that endogenous catecholamines facilitate depolarization-induced automaticity through an increase in calcium conductance was modelled using numerical techniques. It was found that changes in calcium conductance caused changes in the model which closely parallelled the experimental effects of catecholamine depletion and beta-blockade. The effects of changes in delayed rectification in the model did not accurately reproduce the experimental results.

  3. Biphasic effects of acetylstrophanthidin on automaticity in guinea pig ventricular muscle.

    Science.gov (United States)

    Karagueuzian, H S; Katzung, B G

    1982-04-23

    The effects of acetylstrophanthidin (AS) on depolarization-induced automaticity and contractility of guinea pig papillary muscle were studied in a single sucrose gap chamber with microelectrode and current-clamp techniques. The concentration used, 1.4-1.8 microM, never induced automaticity in preparations at their normal resting potential. Twenty min after superfusion with AS, action potential duration (APD) was prolonged and the force of contraction increased. These were associated with an increase in slope of phase 4 depolarization and an increase in the membrane resistance (Rm) of muscles depolarized with small constant current pulses. With longer (50-80 min) periods of AS superfusion, APD became shorter, Rm decreased to less than predrug values, and in depolarized preparations, the slope of phase 4 decreased. Contractility remained unchanged throughout this second phase. All of these effects were fully reversible upon 60 min of superfusion with AS-free Tyrode solution. We suggest that the biphasic effects of AS on the automaticity of depolarized ventricular muscle cells are caused by an initial decrease followed by a later increase in transmembrane potassium conductance.

  4. The effect of open lung ventilation on right ventricular and left ventricular function in lung-lavaged pigs

    NARCIS (Netherlands)

    D.R. Miranda; L. Klompe; F. Cademartiri (Filippo); J.J. Haitsma (Jack); A. Palumbo (Alessandro); B.F. Lachmann (Burkhard); A.J.J.C. Bogers (Ad); D.A.M.P.J. Gommers (Diederik); J.J.M. Takkenberg (Hanneke)

    2006-01-01

    textabstractINTRODUCTION: Ventilation according to the open lung concept (OLC) consists of recruitment maneuvers, followed by low tidal volume and high positive end-expiratory pressure, aiming at minimizing atelectasis. The minimization of atelectasis reduces the right ventricular

  5. Comparison of Cerebral Metabolism between Pig Ventricular Fibrillation and Asphyxial Cardiac Arrest Models

    Institute of Scientific and Technical Information of China (English)

    Yi Zhang; Chun-Sheng Li; Cai-Jun Wu; Jun Yang; Chen-Chen Hang

    2015-01-01

    Background:Morbidity and mortality after resuscitation largely depend on the recovery of brain function.Ventricular fibrillation cardiac arrest (VFCA) and asphyxial cardiac arrest (ACA) are the two most prevalent causes of sudden cardiac death.Up to now,most studies have focused on VFCA.However,results from the two models have been largely variable.So,it is necessary to characterize the features of postresuscitation cerebral metabolism of both models.Methods:Forty-four Wuzhishan miniature inbred pigs were randomly divided into three groups:18 for VFCA group,ACA group,respectively,and other 8 for sham-operated group (SHAM).VFCA was induced by programmed electric stimulation,andACA was induced by endotracheal tube clamping.After 8 min without treatment,standard cardiopulmonary resuscitation (CPR) was initiated.Following neurological deficit scores (NDS) were evaluated at 24 h after achievement of spontaneous circulation,cerebral metabolism showed as the maximum standardized uptake value (SUVmax) was measured by 18F-fluorodeoxyglucose positron emission tomography/computed tomography.Levels of serum markers of brain injury,neuron specific enolase (NSE),and S100β were quantified with an enzyme-linked immunosorbent assay.Results:Compared with VFCA group,fewer ACA animals achieved restoration of spontaneous circulation (61.1% vs.94.4%,P < 0.01) and survived 24-h after resuscitation (38.9% vs.77.8%,P < 0.01) with worse neurological outcome (NDS:244.3 ± 15.3 vs.168.8 ± 9.71,P < 0.01).The CPR duration of ACA group was longer than that of VFCA group (8.1 ± 1.2 min vs.4.5 ± 1.1 min,P < 0.01).Cerebral energy metabolism showed as SUVmax in ACA was lower than in VFCA (P < 0.05 or P < 0.01).Higher serum biomarkers of brain damage (NSE,S100β) were found inACA than VFCA after resuscitation (P < 0.01).Conclusions:Compared with VFCA,ACA causes more severe cerebral metabolism injuries with less successful resuscitation and worse neurological outcome.

  6. Comparison of Cerebral Metabolism between Pig Ventricular Fibrillation and Asphyxial Cardiac Arrest Models

    Directory of Open Access Journals (Sweden)

    Yi Zhang

    2015-01-01

    Full Text Available Background: Morbidity and mortality after resuscitation largely depend on the recovery of brain function. Ventricular fibrillation cardiac arrest (VFCA and asphyxial cardiac arrest (ACA are the two most prevalent causes of sudden cardiac death. Up to now, most studies have focused on VFCA. However, results from the two models have been largely variable. So, it is necessary to characterize the features of postresuscitation cerebral metabolism of both models. Methods: Forty-four Wuzhishan miniature inbred pigs were randomly divided into three groups: 18 for VFCA group, ACA group, respectively, and other 8 for sham-operated group (SHAM. VFCA was induced by programmed electric stimulation, and ACA was induced by endotracheal tube clamping. After 8 min without treatment, standard cardiopulmonary resuscitation (CPR was initiated. Following neurological deficit scores (NDS were evaluated at 24 h after achievement of spontaneous circulation, cerebral metabolism showed as the maximum standardized uptake value (SUVmax was measured by 18 F-fluorodeoxyglucose positron emission tomography/computed tomography. Levels of serum markers of brain injury, neuron specific enolase (NSE, and S100β were quantified with an enzyme-linked immunosorbent assay. Results: Compared with VFCA group, fewer ACA animals achieved restoration of spontaneous circulation (61.1% vs. 94.4%, P < 0.01 and survived 24-h after resuscitation (38.9% vs. 77.8%, P < 0.01 with worse neurological outcome (NDS: 244.3 ± 15.3 vs. 168.8 ± 9.71, P < 0.01. The CPR duration of ACA group was longer than that of VFCA group (8.1 ± 1.2 min vs. 4.5 ± 1.1 min, P < 0.01. Cerebral energy metabolism showed as SUVmax in ACA was lower than in VFCA (P < 0.05 or P < 0.01. Higher serum biomarkers of brain damage (NSE, S100β were found in ACA than VFCA after resuscitation (P < 0.01. Conclusions: Compared with VFCA, ACA causes more severe cerebral metabolism injuries with less successful resuscitation and worse

  7. Enhanced effect of VEGF165 on L-type calcium currents in guinea-pig cardiac ventricular myocytes.

    Science.gov (United States)

    Xing, Wenlu; Gao, Chuanyu; Qi, Datun; Zhang, You; Hao, Peiyuan; Dai, Guoyou; Yan, Ganxin

    2017-01-01

    The mechanisms of vascular endothelial growth factor 165 (VEGF165) on electrical properties of cardiomyocytes have not been fully elucidated. The aim of this study is to test the hypothesis that VEGF165, an angiogenesis-initiating factor, affects L-type calcium currents (ICa,L) and cell membrane potential in cardiac myocytes by acting on VEGF type-2 receptors (VEGFR2). ICa,L and action potentials (AP) were recorded by the whole-cell patch clamp method in isolated guinea-pig ventricular myocytes treated with different concentrations of VEGF165 proteins. Using a VEGFR2 inhibitor, we also tested the receptor of VEGF165 in cardiomyocytes. We found that VEGF165 increased ICa,L in a concentration-dependent manner. SU5416, a VEGFR2 inhibitor, almost completely eliminated VEGF165-induced ICa,L increase. VEGF165 had no significant influence on action potential 90 (APD90) and other properties of AP. We conclude that in guinea-pig ventricular myocytes, ICa,L can be increased by VEGF165 in a concentration-dependent manner through binding to VEGFR2 without causing any significant alteration to action potential duration. Results of this study may further expound the safety of VEGF165 when used in the intervention of heart diseases.

  8. Isoform-specific regulation of the Na+-K+ pump by adenosine in guinea pig ventricular myocytes

    Institute of Scientific and Technical Information of China (English)

    Zhe ZHANG; Hui-cai GUO; Li-nan ZHANG; Yong-li WANG

    2009-01-01

    Aim: The present study investigated the effect of adenosine on Na+-K+ pumps in acutely isolated guinea pig (C, avia sp.) ven-tricular myocytes.Methods: The whole-cell, patch-damp technique was used to record the Na+-K+ pump current (Ip) in acutely isolated guinea pig ventricular myocytes.Results: Adenosine inhibited the high DHO-affinity pump current (Ih) in a concentration-dependent manner, which was blocked by the selective adenosine A1 receptor antagonist DPCPX and the general protein kinase C (PKC) antagonists stau-rosporine, GF 109203X or the specific δ isoform antagonist rottlerin. In addition, the inhibitory action of adenosine was mimicked by a selective A1 receptor agonist CCPA and a specific activator peptide of PKC-δ, PP114. In contrast, the selec-tive A2A receptor agonist CGS21680 and A3 receptor agonist Cl-IB-MECA did not affect lb. Application of the selective A2A receptor antagonist SCH58261 and A3 receptor antagonist MRS1191 also failed to block the effect of adenosine. Further-more, H89, a selective protein kinase A (PKA) antagonist, did not exert any effect on adenosine-induced Ih inhibition.Conclusion: The present study provides the electrophysiological evidence that adenosine can induce significant inhibition of Ih via adenosine A1 receptors and the PKC-δ isoform.

  9. Decreases of voltage-dependent K+ currents densities in ventricular myocytes of guinea pigs by chronic oxidant stress

    Institute of Scientific and Technical Information of China (English)

    De-li DONG; Yan LIU; Yu-hong ZHOU; Wei-hua SONG; He WANG; Bao-feng YANG

    2004-01-01

    AIM: To determine the changes of delayed rectifier K+ currents (Ik) and inward rectifier K+ currents (Ik1) in the ventricular myocytes of guinea pigs during the gradual apoptotic process by the chronic oxidant stress treatment.METHODS: H2O250 μmol/L (24 h) was used for inducing apoptosis in the cardiomyocytes culture of neonatal rats and to treat the isolated ventricular myocytes of adult guinea pigs in vitro for 24 h. Apoptosis was evaluated by TUNEL methods and voltage-dependent K+ currents were recorded by patch-clamp techniques. RESULTS: H2O250 μmol/L (24 h) induced cell apoptosis in the cardiomyocytes culture of neonatal rats. This concentration was used to treat the isolated ventricular myocytes of adult guinea pigs in vitro for 24 h and the voltage-dependent K+currents densities (Ik, Ik1) were down-regulated. The densities of the delayed rectifier K+ currents (Ik) in 50 μmol/L H2O2 group were 2.52±0.57 pA/pF vs 5.73±1.84 pA/pF in the control group at +50 mV (n=8, P<0.01). The densities of the inward rectifier K+ currents (Ik1) in 50 μmol/L H2O2 group were -13.9±2.70 pA/pF, 2.52±0.57 pA/pF vs -59.7± 11.9 pA/pF, 5.73± 1.84 pA/pF in the control group at -120 mV (n=8, P<0.01) and -40 mV (n=8, P<0.05), respectively. The extent of inward rectifier property of Ik1 was weakened by 50μmol/L H2O2 treatment. CONCLUSION: The densities of Ik, Ik1 in the cardiomyocytes of guinea pigs were downregulated and the inward rectifier property of Ik1 was weakened during the gradual apoptotic process after 50 μmol/L H2O2 treatment for 24 h.

  10. Pathophysiological mechanisms of sino-atrial dysfunction and ventricular conduction disease associated with SCN5A deficiency: insights from mouse models

    Directory of Open Access Journals (Sweden)

    Christopher L-H Huang

    2012-07-01

    Full Text Available Genetically modified mice provide a number of models for studying cardiac channelopathies related to cardiac Na+ channel (SCN5A abnormalities. We review key pathophysiological features in these murine models that may underlie clinical features observed in sinus node dysfunction and progressive cardiac conduction disease, thereby providing insights into their pathophysiological mechanisms. We describe loss of Na+ channel function and fibrotic changes associated with both loss and gain-of-function Na+ channel mutations. Recent reports further relate the progressive fibrotic changes to upregulation of TGF-β1 production and the transcription factors, Atf3, a stress-inducible gene, and Egr1, to the presence of heterozygous Scn5a inactivation. Both changes are thus directly implicated in the clinically observed disruptions in sino-atrial node pacemaker function, and sino-atrial and ventricular conduction, and their progression with age. Murine systems with genetic modifications in Scn5a thus prove a useful tool to address questions concerning roles of genetic and environmental modifiers on human SCN5A disease phenotypes.

  11. The effects of quinidine and verapamil on electrically induced automaticity in the ventricular myocardium of guinea pig.

    Science.gov (United States)

    Grant, A O; Katzung, B G

    1976-02-01

    The effects of 2 to 10 muM verapamil (1-5 mg/l) and 3.8 to 7.6 muM quinidine (2-4 mg/l) on automaticity in ventricular myocardial fibers were examined. Papillary muscles from guinea pigs were mounted in a sucrose gap chamber and transmembrane potential was recorded by standard microelectrode techniques. Automaticity was induced with depolarizing currents of various strengths. Verapamil reduced phase 4 slope at all maximum diastolic membrane potentials. It also caused a selective reduction of the overshoot of action potentials arising from less negative maximum diastolic potentials. During exposure to verapamil, increased [Ca]0 partially restored action potential overshoot, but phase 4 slope was further reduced. Epinephrine caused a partial or complete reversal of verapamil-induced phase 4 slope depression but usually did not restore action potential overshoot. Quinidine reduced phase 4 slope at all maximum diastolic potentials. There was less marked reduction of action potential overshoot than in the case of verapamil. Epinephrine caused a partial reversal of the reduction of phase 4 slope produced by quinidine. It is concluded that although both verapamil and quinidine reduce automaticity in ventricular fibers, verapamil may be more effective in reducing the amplitude and occurrence of action potentials arising from low maximum diastolic potentials.

  12. Effects of L-propionylcarnitine on electrical and mechanical alterations induced by amphiphilic lipids in isolated guinea pig ventricular muscle.

    Science.gov (United States)

    Aomine, M; Arita, M; Shimada, T

    1988-01-01

    We examined the effects of L-propionylcarnitine (Prop. C), a short-chain acylcarnitine, on amphiphile (L-lysophosphatidylcholine or L-palmitoylcarnitine)-induced electrophysiological and ultrastructural changes in isolated guinea pig ventricular papillary muscles, under acidic conditions (pH 6.9). Conventional microelectrode, tension-recording, and electron microscope techniques were used. Both amphiphiles, at a concentration of 10(-4) M, significantly decreased the resting membrane potential, action potential amplitude, and action potential duration, but increased the developed and resting tension. Such amphiphile-induced electrical changes were not observed in muscles pretreated with the beta-blocker, atenolol, although the mechanical changes remained unaffected. The application of Prop. C (10(-2) M), in the continued presence of the amphiphiles caused a return of the action potential duration and the developed tension to the control level. However, the resting potential and action potential amplitude remained unaffected; in fact, the maximum upstroke velocity (Vmax) of the action potential tended to decrease further. Pretreatment with Prop. C prevented all the amphiphile-induced electrophysiological and mechanical changes, except for Vmax. Electron microscopic studies revealed that amphiphile-induced ultrastructural changes were prevented, at least in part, in the presence of Prop. C. Thus, Prop. C antagonizes some of deleterious effects of amphiphiles, such as lysophosphatidylcholine and palmitoylcarnitine, upon the electrical and mechanical activities of the ventricular muscle, under acidic conditions.

  13. Effects of Ginkgolide B on action potential and calcium,potassium current in guinea pig ventricular myocytes

    Institute of Scientific and Technical Information of China (English)

    Xiao-yan QI; Zhi-xiong ZHANG; You-qiu XU

    2004-01-01

    AIM: To investigate the effect of Ginkgolide B (GB) on action potential (AP), delayed rectifier potassium current (IK), and L-type calcium current (ICa-L) in guinea pig ventricular myocytes. METHODS: Single ventricular myocytes were isolated by an enzymatic dissociation method. AP, IK, ICa-L were recorded by whole-cell patch-clamp technique in either current or voltage clamp mode. RESULTS: GB shortened APD in a concentration-dependent manner. GB 0.1, 1, and 10 μmol/L shortened APD50 by 7.9 % (n=5, P>0.05), 18.4 % (n=5, P<0.01), and 28.9 % (n=6, P<0.01), respectively; APD90 by 12.4 % (n=5, P>0.05), 17.6 % (n=5, P<0.01), 26.4 % (n=5, P<0.01),respectively. GB increased IK in a concentration-dependent manner. GB 0.1, 1, and l0 μmol/L increased IK by 20.1% (n=6, P<0.05), 43.1% (n=6, P<0.01), 55.6 % (n=6, P<0.05); increased IKtail by 10.7 % (n=6, P<0.05),25.1% (n=6, P<0.05), and 37.7 % (n=6, P<0.05), respectively at testing potential of +50 mV and shift the I-V curve of Ik upward. But GB had no significant effect on ICa-L at above concentrations. CONCLUSION: GB significantly shortened APD in a concentration-dependent manner which mainly due to increase of IK.

  14. Differences of promethazine and terfenadine on ion channels in guinea pig ventricular myocytes

    Institute of Scientific and Technical Information of China (English)

    LI Xue-wen; NIU Shuan-cheng; ZHANG Xuan-ping; L(U) Ji-yuan; BAI Feng; ZHANG Ling; WU Bo-wei

    2006-01-01

    @@ Promethazine, a first generation antihistamine,has an antiarrhythmic effect on ischemia-reperfusion inducing arrhythmias1 and experimental arrhythmias.2 However, terfenadine as a second generation of antihistamine, has been reported to elicit hypotension, bradycardia, prolongation of the QTc interval and torsades de pointes (TdP) like ventricular arrhythmia.3 This may be due to the blockage on rectifier postassium current (Ik) of terfenadine, resulting in the prolongation of the action potential duration (APD) and dispersion of the repolarization duration, which might provoke a specific form of polymorphic ventricular tachydysrhythmia, i.e. TdP.4 In clinical practice,however, the class Ⅲ antiarrhythmic agents, which target on the Ik and prolong the action potential duration and QTc interval, rarely lead to arrhythmias.Other actions must be considered to underlie the arrhythmogenic tendency of terfenadine besides its inhibition on Ik. Though both promethazine and terfenadine block the H1 receptor, there must be a different pharmacology profile between the two compounds on ion channels of cardiac myocytes.Whole-cell patch clamp technique was used to investigate the effects of these two antagonists of the H1 receptor on the main ion currents in cardiac electrical activities.

  15. Inhibitory Effects of Glycyrrhetinic Acid on the Delayed Rectifier Potassium Current in Guinea Pig Ventricular Myocytes and HERG Channel

    Directory of Open Access Journals (Sweden)

    Delin Wu

    2013-01-01

    Full Text Available Background. Licorice has long been used to treat many ailments including cardiovascular disorders in China. Recent studies have shown that the cardiac actions of licorice can be attributed to its active component, glycyrrhetinic acid (GA. However, the mechanism of action remains poorly understood. Aim. The effects of GA on the delayed rectifier potassium current (IK, the rapidly activating (IKr and slowly activating (IKs components of IK, and the HERG K+ channel expressed in HEK-293 cells were investigated. Materials and Methods. Single ventricular myocytes were isolated from guinea pig myocardium using enzymolysis. The wild type HERG gene was stably expressed in HEK293 cells. Whole-cell patch clamping was used to record IK (IKr, IKs and the HERG K+ current. Results. GA (1, 5, and 10 μM inhibited IK (IKr, IKs and the HERG K+ current in a concentration-dependent manner. Conclusion. GA significantly inhibited the potassium currents in a dose- and voltage-dependent manner, suggesting that it exerts its antiarrhythmic action through the prolongation of APD and ERP owing to the inhibition of IK (IKr, IKs and HERG K+ channel.

  16. Relationships between body temperatures and inflammation indicators under physiological and pathophysiological conditions in pigs exposed to systemic lipopolysaccharide and dietary deoxynivalenol.

    Science.gov (United States)

    Tesch, T; Bannert, E; Kluess, J; Frahm, J; Hüther, L; Kersten, S; Breves, G; Renner, L; Kahlert, S; Rothkötter, H-J; Dänicke, S

    2017-03-06

    We studied the constancy of the relationship between rectal and intraabdominal temperature as well as their linkage to inflammatory markers (leucocyte counts, kynurenine-to-tryptophan ratio (Kyn-Trp ratio), tumour necrosis factor alpha (TNF-α) in healthy and in pigs exposed to lipopolysaccharide (LPS) and/or deoxynivalenol (DON). Barrows (n = 44) were fed 4 weeks either a DON-contaminated (4.59 mg DON/kg feed) or a control (CON) diet and equipped with an intraabdominal temperature logger and a multicatheter system (V.portae hepatis, V.lienalis, Vv.jugulares) facilitating infusion of 0.9% NaCl (CON) or LPS (7.5 μg/kg BW) and simultaneous blood sampling. Body temperatures were measured and blood samples taken every 15 min for leucocyte counts, TNF-α and Kyn-Trp ratio. Combination of diet and infusion created six groups: CON_CONjug .-CONpor. , CON_CONjug. -LPSpor. , CON_LPSjug. -CONpor. , DON_CONjug. -CONpor. , DON_CONjug. -LPSpor. , DON_LPSjug. -CONpor. . The relationship between both temperatures was not uniform for all conditions. Linear regression revealed that an intraabdominal increase per 1°C increase in rectal temperature was ~25% higher in all LPS-infused pigs compared to NaCl-infusion, albeit diet and site of LPS infusion modified the magnitude of this difference. Inflammatory markers were only strongly present under LPS influence and showed a significant relationship with body temperatures. For example, leucocyte counts in clinically inconspicuous animals were only significantly correlated to core temperature in DON-fed pigs, but in all LPS-infused groups, irrespective of diet and temperature method. In conclusion, the gradient between body core and rectal temperature is constant in clinically inconspicuous pigs, but not under various pathophysiological conditions. In the latter, measurement of inflammatory markers seems to be a useful completion.

  17. Pathophysiology of the Pericardium.

    Science.gov (United States)

    Hoit, Brian D

    Pericardial heart disease includes pericarditis, (an acute, subacute, or chronic fibrinous, noneffusive, or exudative process), and its complications, constriction, (an acute, subacute, or chronic adhesive or fibrocalcific response), and cardiac tamponade. The pathophysiology of cardiac tamponade and constrictive pericarditis readily explains their respective findings on clinical examination, Doppler echocardiography, and at cardiac catheterization. The primary abnormality of cardiac tamponade is pan-cyclic compression of the cardiac chambers by increased pericardial fluid requiring that cardiac chambers compete for a fixed intrapericardial volume. Features responsible for the pathophysiology include transmission of thoracic pressure through the pericardium and heightened ventricular interdependence. Constrictive pericarditis is a condition in which the pericardium limits diastolic filling and causes dissociation of intracardiac and intrathoracic pressures, and heightened ventricular interdependence. Both conditions result in diastolic dysfunction, elevated and equal venous and ventricular diastolic pressure, respiratory variation in ventricular filling, and ultimately, reduced cardiac output. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Effects of Sevoflurane and Propofol on Organ Blood Flow in Left Ventricular Assist Devices in Pigs

    Directory of Open Access Journals (Sweden)

    Paloma Morillas-Sendín

    2015-01-01

    Full Text Available The aim of this study was to assess the effect of sevoflurane and propofol on organ blood flow in a porcine model with a left ventricular assist device (LVAD. Ten healthy minipigs were divided into 2 groups (5 per group according to the anesthetic received (sevoflurane or propofol. A Biomedicus centrifugal pump was implanted. Organ blood flow (measured using colored microspheres, markers of tissue injury, and hemodynamic parameters were assessed at baseline (pump off and after 30 minutes of partial support. Blood flow was significantly higher in the brain (both frontal lobes, heart (both ventricles, and liver after 30 minutes in the sevoflurane group, although no significant differences were recorded for the lung, kidney, or ileum. Serum levels of alanine aminotransferase and total bilirubin were significantly higher after 30 minutes in the propofol group, although no significant differences were detected between the groups for other parameters of liver function, kidney function, or lactic acid levels. The hemodynamic parameters were similar in both groups. We demonstrated that, compared with propofol, sevoflurane increases blood flow in the brain, liver, and heart after implantation of an LVAD under conditions of partial support.

  19. Temporal response of ectopic activity in guinea pig ventricular myocardium in response to isoproterenol and acetylcholine

    Science.gov (United States)

    Greer-Short, Amara; Poelzing, Steven

    2015-01-01

    Both β adrenergic and muscarinic receptor stimulation independently potentiate arrhythmogenesis. However, the effect of simultaneous stimulation on arrhythmogenesis is not well known. The purpose of this study was to determine the temporal response of arrhythmia risk to individual and combined autonomic agonists. Guinea pig hearts were excised and Langendorff-perfused. The β adrenergic receptor and muscarinic receptor agonists were isoproterenol (ISO, 0.6 μM) and acetylcholine (ACh, 10 μM), respectively. All measurements with agonists occurred over 21 min. ISO induced ectopic activity for the first 8 min. ISO also transiently shortened and then prolonged R-R interval over a similar time course. ACh added after ISO transiently induced ectopic activity for 12 min, while R-R interval invariantly prolonged. ACh alone produced few ectopic beats, while invariantly prolonging R-R interval. In contrast to ISO alone, ISO following ACh significantly increased ectopic activity and shortened R-R interval for the duration of the experiment. Animals aged 17–19 months exhibited sustained arrhythmogenesis while those aged 11–14 did not. When ACh was removed in older hearts while ISO perfused, a transient increase in ectopic activity and decreased R-R interval was observed, similar to ISO alone. These data suggest that pre-treating with and maintaining ACh perfusion can sustain ISO sensitivity, in contrast to ISO perfusion alone. PMID:26539122

  20. The nonlinear elastic and viscoelastic passive properties of left ventricular papillary muscle of a guinea pig heart.

    Science.gov (United States)

    Hassan, M A; Hamdi, M; Noma, A

    2012-01-01

    The mechanical behavior of the heart muscle tissues is the central problem in finite element simulation of the heart contraction, excitation propagation and development of an artificial heart. Nonlinear elastic and viscoelastic passive material properties of the left ventricular papillary muscle of a guinea pig heart were determined based on in-vitro precise uniaxial and relaxation tests. The nonlinear elastic behavior was modeled by a hypoelastic model and different hyperelastic strain energy functions such as Ogden and Mooney-Rivlin. Nonlinear least square fitting and constrained optimization were conducted under MATLAB and MSC.MARC in order to obtain the model material parameters. The experimental tensile data was used to get the nonlinear elastic mechanical behavior of the heart muscle. However, stress relaxation data was used to determine the relaxation behavior as well as viscosity of the tissues. Viscohyperelastic behavior was constructed by a multiplicative decomposition of a standard Ogden strain energy function, W, for instantaneous deformation and a relaxation function, R(t), in a Prony series form. The study reveals that hypoelastic and hyperelastic (Ogden) models fit the tissue mechanical behaviors well and can be safely used for heart mechanics simulation. Since the characteristic relaxation time (900 s) of heart muscle tissues is very large compared with the actual time of heart beating cycle (800 ms), the effect of viscosity can be reasonably ignored. The amount and type of experimental data has a strong effect on the Ogden parameters. The in vitro passive mechanical properties are good initial values to start running the biosimulation codes for heart mechanics. However, an optimization algorithm is developed, based on clinical intact heart measurements, to estimate and re-correct the material parameters in order to get the in vivo mechanical properties, needed for very accurate bio-simulation and for the development of new materials for the

  1. Effects of droperidol on depolarization-induced automaticity, maximum upstroke velocity (Vmax) and the kinetics of recovery of Vmax in guinea-pig ventricular myocardium.

    Science.gov (United States)

    Grant, A O; Hondeghem, L M; Katzung, B G

    1978-04-01

    The neuroleptic drug droperidol has been shown to have clinically useful antiarrhythmic activity. Prior reports have resulted in conflicting conclusions regarding actions on ventricular myocardial fibers. The present study was carried out to determine whether droperidol did in fact affect the electrophysiological properties of guinea-pig papillary muscle fibers. By means of microelectrode recordings from preparations mounted in a single sucrose gap, the effects of concentrations from 10(-6) to 4 X 10(-5) M were studied on depolarization-induced automaticity, and on Vmax and its recovery time under several conditions of membrane potential, stimulation rate and external ion concentration. The results showed that at clinically relevant concentrations, droperidol significantly slows ventricular pacemaker activity, a depression reversible by epinephrine. Furthermore, Vmax was decreased and the time constant for Vmax recovery was significantly prolonged under several conditions which pertain to clinical arrhythmias, i.e., reduced membrane potential, elevated extracellular potassium concentrations and increased stimulation rate.

  2. A xanthine derivative denbufylline inhibits negative inotropic response to verapamil in guinea pig ventricular papillary muscles, independent of its phosphodiesterase inhibitory activity.

    Science.gov (United States)

    Sanae, F; Ohmae, S; Takagi, K; Miyamoto, K

    1995-11-01

    A phosphodiesterase (PDE) III inhibitor, amrinone, inhibited both the negative inotropic actions of verapamil and nicardipine in guinea pig ventricular papillary muscle; this effect was canceled by the protein kinase A inhibitor H-89. The PDE IV inhibitor 1,3-di-n-butyl-7-(2'-oxopropyl)xanthine (denbufylline), which elicited a negative inotropic action by itself, attenuated the action of verapamil up to 10 microM, without any interaction with nicardipine. The attenuation by denbufylline was not influenced by H-89. This suggests that in the ventricular papillary muscle, denbufylline acts on some verapamil-sensitive site(s) in the membrane and interferes with the calcium channel function without involvement of its PDE inhibitory activity.

  3. Electrophysiological effects of Chinese medicine Shen song Yang xin (SSYX) on Chinese miniature swine heart and isolated guinea pig ventricular myocytes

    Institute of Scientific and Technical Information of China (English)

    FENG Li; GONG Jing; JIN Zhen-yi; LI Ning; SUN Li-ping; WU Yi-ling; PU Jie-lin

    2009-01-01

    Background Shen song Yang xin (SSYX) is a compound of Chinese medicine with the effect of increasing heart rate (HR). This study aimed to evaluate its electrophysiological properties at heart and cellular levels. Methods The Chinese miniature swines were randomly assigned to two groups, administered with SSYX or placebo for 4 weeks (n=8 per group). Cardiac electrophysiological study (EPS) was performed before and after drug administration. The guinea pig ventricular myocytes were enzymatically isolated and whole cell voltage-clamp technique was used to evaluate the effect of SSYX on cardiac action potential (AP). Results SSYX treatment accelerated the HR from (141.8±36.0) beats per minute to (163.0±38.0) beats per minute (P=0.013) without changing the other parameters in surface electrocardiogram. After blockage of the autonomic nervous system with metoprolol and atropin, SSYX had no effect on intrinsic HR (IHR), but decreased corrected sinus node recovery time (CSNRT) and sinus atrium conducting time (SACT). Intra cardiac EPS showed that SSYX significantly decreased the A-H and A-V intervals as well as shortened the atrial (A), atrioventricular node (AVN) and ventricular (V) effective refractory period (ERP). In isolated guinea pig ventricular myocytes, the most obvious effect of SSYX on action potential was a shortening of the action potential duration (APD) without change in shape of action potential. The shortening rates of APD30, APD50 and APDgo were 19.5%, 17.8% and 15.3%, respectively. The resting potential (Em) and the interval between the end of APD3o and APD9o did not significantly change.Conclusions The present study demonstrates that SSYX increases the HR and enhances the conducting capacity of the heart in the condition of the intact autonomic nervous system. SSYX homogenously decreases the ERP of the heart and shortens the APD of the myocytes, suggesting its antiarrhythmic effect without proarrhythmia.

  4. Beneficial effects of the Ca2+ sensitizer EMD 57033 in exercising pigs with infarction-induced chronic left ventricular dysfunction.

    NARCIS (Netherlands)

    D.J.G.M. Duncker (Dirk); D.B. Haitsma; D. Liem (Djien); N. Heins; R. Stubenitsky (René); P.D. Verdouw (Pieter)

    2001-01-01

    textabstract1. It is unknown how cardiac stimulation by Ca(2+) sensitization modulates the cardiovascular response to exercise when left ventricular (LV) function is chronically depressed following a myocardial infarction. We therefore investigated the effects of EMD 57033 at rest

  5. Low oxygen tension induces positive inotropy and decreases a(i)Na in isolated guinea-pig cardiac ventricular papillary muscles.

    Science.gov (United States)

    Jao, M J; Yang, J M

    1998-06-30

    Effects of low oxygen on contractile force, intracellular Na+ activity (aiNa), and action potential were simultaneously measured in isolated guinea-pig ventricular papillary muscles. Reduction of oxygen from control 488 to 150 mmHg biphasically increased and decreased the twitch tension, and decreased aiNa in muscles driven at 60 beats/min. The action potential duration (APD) was decreased but the maximum rate of upstroke (Vmax) was increased. In control, 1 microM epinephrine significantly increased the the action potential amplitude and twitch tension with decreases in the time to twitch peak (TTP), time for 50% relaxation (RT50), and aiNa. After exposure to low oxygen for 10 min, with twitch tension elevated and TTP and RT90 increased, 1 microM epinephrine significantly increased the twitch tension and Vmax, and decreased the APD and aiNa. Pretreatment with reserpine inhibited the twitch tension, both at control and in the presence of epinephrine. But changes of action potential and aiNa in response to low oxygen and epinephrine were similar to those in control. Our results indicate that the isolated guinea-pig ventricular muscle needs a high oxygen tension to maintain a normal contractile function. Reduction of oxygen deteriorates the electrical and mechanical activities, most likely, by a coaxial graded hypoxia. The decreased aiNa, not associated with endogenous catecholamines, suggests that the activity of the Na(+)-K+ pump can be maintained in the superficial muscle cells despite of core-central hypoxia.

  6. Application of Positron Emission TomographyintheDetection of Myocardial Metabolism inPigVentricularFibrillation and Asphyxiation Cardiac Arrest ModelsafterResuscitation

    Institute of Scientific and Technical Information of China (English)

    WUCaiJun; LIChunSheng; ZHANGYi; YANGJun

    2014-01-01

    ObjectiveTo study the application of positron emission tomography (PET) in detection of myocardial metabolism in pig ventricular fibrillation and asphyxiation cardiac arrest models after resuscitation. MethodsThirty-two healthyminiature pigs were randomized into aventricular fibrillation cardiac arrest (VFCA) group (n=16) and an asphyxiation cardiac arrest (ACA)group (n=16). Cardiac arrest (CA) was induced byprogrammed electric stimulationorendotracheal tube clamping followed by cardiopulmonary resuscitation (CPR) anddefibrillation. At four hours and 24 h afterspontaneous circulation was achieved, myocardial metabolism was assessed by PET.18F-FDG myocardial uptake in PET was analyzed and the maximum standardized uptake value (SUVmax) was measured. ResultsSpontaneous circulation was 100% and 62.5% in VFCA group and ACA group, respectively.PET demonstrated that the myocardial metabolism injuries was more severe and widespread after ACA than after VFCA. The SUVmax was higher in VFCA group than in ACA group (P<0.01).In VFCA group,SUVmaxat 24h after spontaneous circulation increased to the level of baseline. ConclusionACA causes more severe cardiac metabolism injuries than VFCA. Myocardial dysfunction is associated with less successful resuscitation. Myocardial stunning does occur with VFCA but not with ACA.

  7. Amrinone effects on electromechanical coupling and depolarization-induced automaticity in ventricular muscle of guinea pigs and ferrets.

    Science.gov (United States)

    Malécot, C O; Arlock, P; Katzung, B G

    1985-01-01

    The effects of the cardiotonic agent, amrinone (0.05-4 mM), on electrical and mechanical activities of ferret and guinea-pig papillary muscles were studied using current and voltage clamp (single sucrose gap) techniques. In current clamp studies, amrinone increased, in a dose-dependent manner, contractile force elicited by action potential in both species. Depolarization-induced automaticity was facilitated in ferret muscles at all maximum diastolic potentials between -70 and -15 mV. Facilitation of automaticity in guinea-pig muscles occurred only at potentials more negative than -35 mV and was suppressed at more positive potentials. Cimetidine (10 microM) partially reversed the effects of amrinone on automaticity in both species. In voltage clamp studies, amrinone increased the slow inward current. Steady-state outward current was increased in guinea-pig but not in ferret muscles. A dual effect of amrinone on tension was observed. Amrinone was found to increase phasic tension of ferret papillary muscles only for depolarizations lasting less than 250 to 300 msec. For longer depolarizations, amrinone decreased the phasic tension (in a dose-dependent manner), whereas the tonic tension was not modified. The decrease as well as the increase in tension was associated with an increase of the slow inward current. The results suggest that amrinone may be arrhythmogenic and may have an intracellular action at the sarcoplasmic reticulum level (partial inhibition) in addition to its action on the calcium current.

  8. Treatment of ethanol-induced acute pulmonary hypertension and right ventricular dysfunction in pigs, by sildenafil analogue (UK343-664 or nitroglycerin

    Directory of Open Access Journals (Sweden)

    Sidi Avner

    2008-01-01

    Full Text Available In patients at risk for sudden ethanol (ETOH intravascular absorption, prompt treatment of pulmonary hypertension (PHTN will minimise the risk of cardiovascular decompensation. We investigated the haemodynamic effects of intravenous ETOH and the pulmonary vasodilatory effects of a sildenafil analogue (UK343-664 and nitroglycerin (NTG during ETOH-induced PHTN in pigs. We studied pulmonary and systemic haemodynamics, and right ventricular rate or time derivate of pressure rise during ventricular contraction ( =dP/dT, as an index of contractility, in 23 pigs. ETOH was infused at a rate of 50 mg/kg/min, titrated to achieve a twofold increase in mean pulmonary arterial pressure (MPAP, and then discontinued. The animals were randomised to receive an infusion of 2 ml/kg ( n = 7 normal saline, a 500-μg/kg bolus of UK343-664 ( n = 8, or NTG 1 μg/kg ( n = 8; each was given over 60 seconds. Following ETOH infusion, dP/dT decreased central venous pressure (CVP, and MPAP increased significantly, resulting in significantly increased pulmonary vascular resistance (PVR. Within 2 minutes after treatment with either drug, CVP, heart rate (HR, and the systemic vascular resistance-to-pulmonary vascular resistance (SVR/PVR ratio returned to baseline. However, at that time, only in the UK343-664 group, MPAP and dP/dT partially recovered and were different from the respective values at PHTN stage. NTG and UK343-664 decreased PVR within 2 minutes, from 1241±579 and 1224±494 dyne · cm/sec 5 , which were threefold-to-fourfold increased baseline values, to 672±308 and 538±203 dyne · cm/sec 5 respectively. However, only in the UK343-664 group, changes from baseline PVR values after treatment were significant compared to the maximal change during target PHTN. Neither drug caused a significant change in SVR. In this model of ETOH-induced PHTN, both UK343-664 and NTG were effective pulmonary vasodilators with a high degree of selectivity. However, the changes from

  9. Effects of Arecoline on Calcium Channel Currents and Caffeine-induced Calcium Release in Isolated Single Ventricular Myocyte of Guinea Pig

    Institute of Scientific and Technical Information of China (English)

    林先明; 李真; 胡本容; 夏国瑾; 姚伟星; 向继洲

    2002-01-01

    Summary: The effects of Arecoline (Are) on calcium mobilization were investigated. In isolatedsingle ventricular myocyte of guinea pig, patch clamp whole cell recording techniques were used torecord the current of L-type calcium channel and cytosolic Ca2+ level ([Ca2+]i) labeled with fluo-rescence probe Fluo-3/AM was measured under a laser scanning confocal microscope. Results re-vealed that Are (3-100 μmol/L) could inhibit L-type calcium current in a concentration-depen-dent manner and the value of IC50 was 33. 73μmol/L (n= 5). In the absence of extracellular calci-um, the resting levels of [Ca2+]i was not affected by Are (n=6, P>0. 05), but pretreatmentwith Are (30 μmol/L) could significantly inhibit the [Ca2+]i elevation induced by caffeine (10mmol/L, n = 6, P < 0. 01). It was concluded that Are could inhibit not only calcium influxthrough L-type calcium channel but also calcium release from sarcoplasmic reticulum.

  10. Effects of changes in frequency on guinea pig ventricular action potential duration and on QT interval under different experimental conditions.

    Science.gov (United States)

    von Savigny, L; Hohnloser, S; Antoni, H

    1981-01-01

    Isolated perfused guinea pig hearts (Langendorff preparation) were arrested by carbachol (0.1-0.2 mg/l) and electrically stimulated in the region of the av-conducting system. The QT interval was determined by means of extracellular electrodes at different driving frequencies. Separate experiments were performed on papillary muscles from the right ventricle to measure the duration of the transmembrane action potential under comparable conditions. At 35 degrees C (Ke+ 5.4 mmol/l) increasing the frequency of stimulation (range 12-120/min) caused the action potential duration (APD) to decrease to a greater extent than the QT interval. Stepwise rising of the external K+ concentration up to 16.2 mmol/l produced a nearly parallel shift to the APD-frequency relation to lower values. Again, the QT interval was less affected by increasing the external K+ concentration than the APD. Stepwise reduction of the temperature down to 20 degrees C prolonged the APD as well as the QT interval, the effects being more pronounced at lower than at higher stimulation frequencies. Under all examined experimental conditions, the APD proved to be markedly shorter than the QT interval even when the latter is diminished by the duration of QRS. The results suggest that no close relation exists between the APD and the QT interval. The observed divergencies may be due to functional differences among various parts of the ventricles.

  11. Bepridil differentially inhibits two delayed rectifier K(+) currents, I(Kr) and I(Ks), in guinea-pig ventricular myocytes.

    Science.gov (United States)

    Wang, J C; Kiyosue, T; Kiriyama, K; Arita, M

    1999-12-01

    1. We investigated the effects of bepridil on the two components of the delayed rectifier K(+) current, i.e., the rapidly activating (I(Kr)) and the slowly activating (I(Ks)) currents using tight-seal whole-cell patch-clamp techniques in guinea-pig ventricular myocytes, under blockade of L-type Ca(2+) current with nitrendipine (5 microM) or D600 (1 microM). 2. Bepridil decreased I(Ks) under blockade of I(Kr) with E4031 (5 microM), in a concentration-dependent manner. The concentration-dependent inhibition of I(Ks) by bepridil was fitted by a curve, assuming one-to-one interactions between the channel and the drug molecule. The concentration of half-maximal inhibition (IC(50)) was found to be 6.2 microM. 3. The effect of bepridil on I(Kr) was assessed using an envelope-of-tails test. In the control condition, a ratio of the tail current to the time-dependent current measured during depolarization was large (>1) at shorter pulses (coefficient=3.03) and the IC(50) was 13.2 microM. 5. These results suggest that bepridil at a clinical therapeutic concentration ( approximately 2 microM) selectively blocks I(Ks) but does not inhibit I(Kr). This may relate to the characteristic frequency-dependent effects of bepridil on the action potential duration (APD), e.g., the non-reverse use-dependent prolongation of APD.

  12. Pathophysiology of Takotsubo Syndrome.

    Science.gov (United States)

    Pelliccia, Francesco; Kaski, Juan Carlos; Crea, Filippo; Camici, Paolo G

    2017-06-13

    Originally described by Japanese authors in the 1990s, Takotsubo syndrome (TTS) generally presents as an acute myocardial infarction characterized by severe left ventricular dysfunction. TTS, however, differs from an acute coronary syndrome because patients have generally a normal coronary angiogram and left ventricular dysfunction, which extends beyond the territory subtended by a single coronary artery and recovers within days or weeks. The prognosis was initially thought to be benign, but subsequent studies have demonstrated that both short-term mortality and long-term mortality are higher than previously recognized. Indeed, mortality reported during the acute phase in hospitalized patients is ≈4% to 5%, a figure comparable to that of ST-segment-elevation myocardial infarction in the era of primary percutaneous coronary interventions. Despite extensive research, the cause and pathogenesis of TTS remain incompletely understood. The aim of the present review is to discuss the pathophysiology of TTS with particular emphasis on the role of the central and autonomic nervous systems. Different emotional or psychological stressors have been identified to precede the onset of TTS. The anatomic structures that mediate the stress response are found in both the central and autonomic nervous systems. Acute stressors induce brain activation, increasing bioavailability of cortisol and catecholamine. Both circulating epinephrine and norepinephrine released from adrenal medullary chromaffin cells and norepinephrine released locally from sympathetic nerve terminals are significantly increased in the acute phase of TTS. This catecholamine surge leads, through multiple mechanisms, that is, direct catecholamine toxicity, adrenoceptor-mediated damage, epicardial and microvascular coronary vasoconstriction and/or spasm, and increased cardiac workload, to myocardial damage, which has a functional counterpart of transient apical left ventricular ballooning. The relative preponderance

  13. Differential effects of L-propionylcarnitine on the electrical and mechanical properties of guinea pig ventricular muscle in normal and acidic conditions.

    Science.gov (United States)

    Aomine, M; Arita, M

    1987-11-01

    We studied the effects of L-propionylcarnitine (PC) on transmembrane action potentials and isometric contractile tension in isolated guinea pig ventricular papillary muscles. The effects of 5 concentrations of PC (10(-5), 10(-4), 10(-3), 10(-2) and 3 X 10(-2)M) were examined in both normal (pH 7.4) and acidic (pH 6.9) conditions. The concentrations of 10(-5) to 10(-2)M had no significant effect on action potential amplitude, maximum upstroke velocity of phase 0 and resting potential, in either condition. At pH 7.4, action potential duration (ADP) was significantly (P less than 0.05) or insignificantly shortened by the drug depending upon the concentration used. At pH 6.9, however, the APD was prolonged by moderate PC concentrations (10(-3) and 10(-2)M), in which the effective refractory period (ERP) was also lengthened, associated with an increased ERP/APD ratio. In both pH conditions, the highest concentration (3 X 10(-2)M) significantly (P less than 0.05) decreased all these action potential parameters. PC had a biphasic effect on the developed tension. In both pH conditions, low PC concentrations (10(-5) to 10(-3)M) produced an initial augmentation of the contraction, followed by subsequent reduction. The initial augmentation disappeared by pretreatment with reserpine or propranolol, suggesting the involvement of beta-adrenoceptors. In the steady state, all PC concentrations produced a negative inotropic effect at pH 7.4, while at pH 6.9 only high concentrations (10(-2)M and 3 X 10(-2)M) had this effect. These results suggest that the effects of PC in an acidic condition differ considerably from those in a normal pH condition and that limited concentrations of PC (10(-3) to 10(-2)M) may prevent re-entrant arrhythmias from developing under acidic conditions via lengthening of the ERP, without deleterious effects on the contractile force.

  14. Pathophysiology of shunt dysfunction in shunt treated hydrocephalus

    DEFF Research Database (Denmark)

    Blegvad, C.; Skjolding, A D; Broholm, H

    2013-01-01

    We hypothesized that shunt dysfunction in the ventricular catheter and the shunt valve is caused by different cellular responses. We also hypothesized that the cellular responses depend on different pathophysiological mechanisms....

  15. 乙酰胆碱对离体豚鼠心室肌的直接作用机制探讨%The mechanisms underlying the effects of acetylcholine on isolated guinea-pig ventricular myocytes

    Institute of Scientific and Technical Information of China (English)

    方萍; 张晓东; 等

    2001-01-01

    To investigate the mechanisms underlying the effects of ACh on isolated guinea-pig ventricular myocytes. METHODS: Using standard microelectrodes and force transducer we recorded the effects of ACh (10-5 mol/L) and various blockers such as atropine, CsCl and CdCl2 on the action potential and force contraction in isolated ventricular myocytes of guinea-pig. RESULTS: ACh(10-5 mol/L) reduced the duration of action potential and twitch tensions by 7.31% and 37.57% respectively (P<0.05),which could be blocked by atropine, CsCl, but not by CdCl2. CONCLUSION: ACh (10-5 mol/L) could cause a negative chronotropic and inotropic effects on guinea-pig ventricular myocytes. These effects are related to the muscarinic receptor and the potassium channel and may not related to the calcium channel.%目的: 研究乙酰胆碱(ACh)对离体豚鼠心室肌的直接负性作用及机制。方法: 采用标准玻璃微电极细胞内记录技术记录动作电位(AP)及肌力换能器记录心肌收缩力(FC)的方法观察ACh对离体豚鼠心室肌的作用,并观察几种受体或通道水平的阻断剂阿托品、氯化铯(CsCl)、氯化镉(CdCl2)对ACh直接作用的影响。结果: 10-5mol/L ACh对心室肌动作电位持续时间(APD)及FC的抑制率分别为7.31%和37.57%(P<0.05),10-5 mol/L阿托品和20 mmol/L CsCl可阻断该作用,0.1 mmol/L CdCl2对该作用无影响。结论: 10-5mol/L ACh 对离体豚鼠心室肌有直接负性作用,ACh的作用与毒蕈碱型胆碱受体及K+电流有关,而与Ca2+电流的关系可能不大。

  16. Effect of temperature on the activation of myocardial KATP channel in guinea pig ventricular myocytes: a pilot study by whole cell patch clamp recording

    Institute of Scientific and Technical Information of China (English)

    JIN San-qing; NIU Li-jun; DENG Chun-yu; YAO Zhi-bin; ZHOU Ying-jie

    2006-01-01

    Background The myocardial ATP sensitive potassium channel (KATP channel) has been known for more than two decades, the properties of this channel have been intensively investigated, especially the myocardial protection effect by opening this channel. Numerous studies, including hypothermic, using KATP agonists to achieve a hyperpolarizing cardioplegic arrest, have shown a better myocardial protection than potassium arrest.However, there is no evidence showing that KATP channel could be opened by its agonists under profound hypothermia. We investigated the effect of temperature on activation of myocardial KATP channel by nicorandil.Methods Isolated ventricular myocytes were obtained by collagenase digestion of the hearts of guinea pigs and stored in KB solution at 4℃. With a steady ground current, the myocytes were perfused with 1 mmol/L nicorandil until a steady IKATP occurred. Then the cells were perfused with 1 mmol/L nicorandil plus 1 μmol/L glybenclamide. Currents signals were recorded on whole cells using patch clamp technique at several temperatures. The temperature of the bath solution around myocytes was monitored and was controlled at 4℃,10℃, 20℃, 25℃ and 35℃ respectively. About 10 cells were tested at each temperature, the cells were considered useful only when the outward current could be induced by nicorandil and blocked by glybenclamide.All data were analyzed using Graphpad PRISM 3.0 (Graphpad, San Diego, CA, USA). Nonlinear curve fitting was done in Clampfit (Axon) or Sigmaplot (SPSS).Results At 4℃, 10℃, 20℃, 25℃ and 35℃, the time needed to open the myocardial KATP channel was (81.0±0)minutes, (50.5±11.7) minutes, (28.8±2.3) minutes, (9.4±10.2) minutes and (2.3± 1.0) minutes respectively (P=0.003). The linear relationship between temperature and time needed to open the channel was y (min) =(4348.790-124.277x)/60, where y (min) is time needed to open KATP channel, x is temperature, correlation coefficient r =-0.942 (P=0

  17. Antiarrhythmic Effect of Either Negative Modulation or Blockade of Small Conductance Ca2+-activated K+ Channels on Ventricular Fibrillation in Guinea Pig Langendorff-perfused Heart

    DEFF Research Database (Denmark)

    Diness, Jonas G.; Kirchhoff, Jeppe E.; Sheykhzade, Majid;

    2015-01-01

    channels are predominantly coming into play during arrhythmogenic events where intracellular concentration of Ca is increased. During ventricular fibrillation a surge of [Ca]i has the potential to bind to and open SK channels. To obtain mechanistic insight into possible roles of SK channels during...... ventricular fibrillation we conducted experiments with a SK channel pore blocker (ICA) and a negatively allosteric modulator (NS8395) in a Langendorff perfused heart model. Both compounds increased the action potential duration (APD), effective refractory period (ERP) and Wenckebach cycle length (WCL......) to comparable extents. Despite these similarities, the SK channel modulator was found to revert and prevent ventricular fibrillation (VF) more efficiently than the SK channel pore blocker. In conclusion, either negative allosteric modulation of the SK channel with NS8593 is more favorable than pure channel...

  18. Effects of astragaloside Ⅳ on electrocardiogram and action potential of ventricular myocytes in guinea pigs%黄芪甙Ⅳ对豚鼠心电图及心室肌动作电位的影响

    Institute of Scientific and Technical Information of China (English)

    周云; 王俊杰; 赵伟; 张川; 张卫东

    2009-01-01

    Objective To observe the effects of astragaloside Ⅳ on electrocardiogram (ECG) and action potential of ventricular myocytes in guinea pigs. Methods ECG was recorded in vivo and ex vivo by using conventional ECG recording method from anesthetic guinea pigs and Langendoff perfusion model of hearts. Action potentials were recorded from isolated papillary muscles of right ventricles of guinea pigs by using microelectrode techniques. Results RR interval was prolonged by Astragaloside Ⅳ in a dose-dependent manner both in vivo and ex vivo. Astragaloside Ⅳ shortened action potential duration (APD), while had no effects on resting potential, action potential amplitude and maximal rate of depolarization. Conclusion Astragaloside Ⅳ exerts a negative chronotropic effect on heart and shortens APD of cardiac myocytes, which may be involved with calcium channels.%目的 观察黄芪甙Ⅳ对豚鼠心电图(ECG)及心室肌动作电位的影响.方法 分别在麻醉豚鼠和Langendoff心脏灌流模型上记录体表ECG和离体心脏ECG,采用细胞内微电极技术记录豚鼠右心室乳头肌的动作电位.结果 黄芪甙Ⅳ能延长豚鼠体表ECG和离体心脏ECG的RR间期,这一效应具有剂量依赖性.黄芪甙Ⅳ还能缩短动作电位的时程(APD),但对静息电位、动作电位幅度和最大去极速度没有明显影响.结论 黄芪甙Ⅳ具有负性变时作用,能缩短心肌细胞APD,其作用机制可能与慢钙通道有关.

  19. Right Ventricular Imaging and Computer Simulation for Electromechanical Substrate Characterization in Arrhythmogenic Right Ventricular Cardiomyopathy

    NARCIS (Netherlands)

    Mast, TP; Teske, Arco J; Walmsley, John; van der Heijden, Jeroen F; van Es, René; Prinzen, Frits W; Delhaas, Tammo; van Veen, Toon A; Loh, KP; Doevendans, Pieter A; Cramer, Maarten J; Lumens, Joost

    2016-01-01

    BACKGROUND: Previous studies suggested that electrical abnormalities precede overt structural disease in arrhythmogenic right ventricular cardiomyopathy (ARVC). Abnormal RV deformation has been reported in early ARVC without structural abnormalities. The pathophysiological mechanisms underlying thes

  20. 4-氨基吡啶对豚鼠心室肌钙和钠电流的影响%EFFECTS OF 4-AMINOPYRIDINE ON CALCIUM CURRENTS AND SODIUM CURRENTS IN GUINEA PIG VENTRICULAR MYOCYTES

    Institute of Scientific and Technical Information of China (English)

    傅丽英; 李泱; 夏国瑾; 姚伟星; 江明性

    2001-01-01

    目的研究4-氨基吡啶(4-AP)对心肌细胞L型钙通道和钠通道的影响。方法用全细胞膜片钳技术考察4-AP对豚鼠心室肌细胞L型钙电流和钠电流的作用。结果 4-AP 0.1, 0.5, 1.0 mmol*L-1浓度依赖性地抑制L型钙电流(ICa,L)和钠电流(INa),抑制率分别为(11.6±1.7)%,(37.5±8.3)%和(54.5±6.9)%以及(22.1±14.3)%,(39.4±8.8)%和(62.3±6.8)%。0.5 mmol*L-1 4-AP使ICa,L和INa I-V曲线均上移。结论 4-AP可浓度依赖性地阻滞豚鼠心室肌细胞L型钙通道和钠通道。%AIM To investigate the effect of 4-aminopyridine (4-AP) on ion channels of myocytes. METHODS L-type calcium channel and sodium channel currents were recorded in guinea pig single ventricular myocyte using whole-cell patch-clamp techniques. RESULTS 4-AP, 0.1, 0.5 and 1.0 mmol*L-1 were shown to inhibit L-type calcium channel currents (ICa,L) and sodium channel currents (INa) concentration-dependently. The percentage of inhibition were (11.6±1.7)%, (37.5±8.3)% and (54.5±6.9)% (P<0.01) respectively for ICa,L, and (22.1±14.3)% (P<0.05), (39.4±8.8)% and (62.3±6.8)% (P<0.01) respectively for INa. 4-AP 0.5 mmol*L-1 shifted the I-V curves of ICa,L and INa upwardly. CONCLUSION 4-AP blocked L-type calcium channel and sodium channels in guinea-pig ventricular myocytes concentration-dependently.

  1. Unilateral ventricular reflux and asymmetric ventricular distribution of intrathecally introduced contrast medium or tracer

    Energy Technology Data Exchange (ETDEWEB)

    Deisenhammer, E.; Hammer, B.

    Fourteen cases of totally or predominantly unilateral ventricular reflux and stasis of intrathecally injected radioisotope or contrast medium were demonstrated by scintigraphy or computed tomographic cisternography. All showed asymmetric enlargement of the lateral ventricles and nine had ipsilateral brain lesions. Four case reports are presented. The pathophysiologic mechanism of communicating hydrocephalus and possible causes of unilateral ventricular reflux are discussed, as well as indications for ventricular shunt installation.

  2. Pathophysiology of heart failure.

    Science.gov (United States)

    Chiariello, M; Perrone-Filardi, P

    1999-01-01

    Heart failure is a leading cause of mortality and morbidity in Western countries. Common etiology is mostly represented by ischemic and hypertensive heart disease. Clinically, heart failure can be defined as an impaired cardiac performance, unable to meet the energy requirements of the periphery. Pathophysiologically, the clinical onset of heart failure symptoms already represents an advanced stage of disease when compensatory mechanisms triggered by the underlying decrease in contractility are no longer capable of maintaining adequate cardiac performance during exercise and, subsequently, under resting conditions. Independent of its underlying etiology, cardiac failure is always characterized by an impairment in the intrinsic contractility of myocytes. As a consequence of reduced contractility, a number of central and peripheral compensatory mechanisms take place that are capable of effectively counteracting reduced intravascular intrinsic performance for a long period of time. Among them, recruitment of preload reserve, enhanced neurohormonal stimulation and cardiac hypertrophy are the most important. All of them, however, also carry unfavorable effects that contribute to further deterioration of cardiac function. In fact, increased end-diastolic volume determines increased wall stress that further reduces systolic performance; sympathetic and angiotensin stimulation increases peripheral resistance and contributes to increase volume expansion; hypertrophic myocytes demonstrate impaired intrinsic contractility and relaxation, and hypertrophy causes a clinically relevant deterioration of ventricular relaxation and compliance that substantially participates in increased end-diastolic pressure, and, therefore, to limited exercise performance. Diastolic dysfunction usually accompanies systolic dysfunction, although in some cases it may represent the prevalent mechanism of congestive heart failure in patients in whom systolic performance is preserved. Biological causes

  3. Ventricular assist device

    Science.gov (United States)

    VAD; RVAD; LVAD; BVAD; Right ventricular assist device; Left ventricular assist device; Biventricular assist device; Heart pump; Left ventricular assist system; LVAS; Implantable ventricular assist device

  4. DOCA-salts induce heart failure in the guinea pig.

    Science.gov (United States)

    Tiritilli, A

    2001-10-01

    Heart failure (HF) is a common clinical problem confronting physicians and is often the final manifestation of many cardiovascular disorders. Despite recent advances in the pharmacological management of HF, it remains a highly lethal and disabling disorder. A number of animal models have been developed to study both the pathophysiology of HF and new therapeutic approaches to this complex syndrome. Only through an improved understanding of the basic biology of the early stages of the syndrome can HF be prevented or at least anticipated. With this in view, we have developed an easily realisable and inexpensive model in the guinea pig, which presents numerous structural, metabolic and biochemical similarities compared with the human heart. Thirty guinea pigs, aged 5 weeks and weighing 300 g were used. After anaesthesia, left nephrectomy was performed. After 1 week the guinea pigs were divided into: (a) control group (n=15), which received an injection of vehicle as well as tap water for 10 weeks; (b) DOCA-salts group (n=15), where the animals were treated with an IM injection of 10 mg DOCA 5 days a week for 10 weeks and with drinking water containing 9 g/l(-1) NaCl and 2 g/l(-1) KCl. Our results demonstrate that the administration of DOCA-salts to guinea pigs for 10 weeks caused a significant increase in blood pressure (BP+30%) associated with left ventricular hypertrophy (LVH), evaluated by LV weight (+37%), LV wall (+36%), by the ratio LV weight/Body weight (+23%) and by an increase in LV volume (+51%). Concerning HF, the latter was clinically evident through an increase in body weight, heart rate and dyspnoea. Indeed, guinea pigs presented pleural and/or pericardial effusion often associated with ascite. This model, which combines pressure and volume overload, results in a slow evolution towards HF. This allows a better understanding of the mechanisms in early LV remodelling which has the potential to develop into HF. Some recent studies have emphasised the value

  5. Antiarrhythmic Effect of Either Negative Modulation or Blockade of Small Conductance Ca2+-activated K+ Channels on Ventricular Fibrillation in Guinea Pig Langendorff-perfused Heart.

    Science.gov (United States)

    Diness, Jonas G; Kirchhoff, Jeppe E; Sheykhzade, Majid; Jespersen, Thomas; Grunnet, Morten

    2015-09-01

    During recent years, small conductance Ca-activated K (SK) channels have been reported to play a role in cardiac electrophysiology. SK channels seem to be expressed in atria and ventricles, but from a functional perspective, atrial activity is predominant. A general notion seems to be that cardiac SK channels are predominantly coming into play during arrhythmogenic events where intracellular concentration of Ca is increased. During ventricular fibrillation (VF), a surge of [Ca]i has the potential to bind to and open SK channels. To obtain mechanistic insight into possible roles of SK channels during VF, we conducted experiments with an SK channel pore blocker (ICA) and a negatively allosteric modulator (NS8395) in a Langendorff-perfused heart model. Both compounds increased the action potential duration, effective refractory period, and Wenckebach cycle length to comparable extents. Despite these similarities, the SK channel modulator was found to revert and prevent VF more efficiently than the SK channel pore blocker. In conclusion, either negative allosteric modulation of the SK channel with NS8593 is more favorable than pure channel block with ICA or the 2 compounds have different selectivity profiles that makes NS8593 more antiarrhythmic than ICA in a setting of VF.

  6. Effect of lidocaine and quinidine on steady-state characteristics and recovery kinetics of (dV/dt)max in guinea pig ventricular myocardium.

    Science.gov (United States)

    Chen, C M; Gettes, L S; Katzung, B G

    1975-07-01

    We studied the effects of quinidine and lidocaine on the steady-state relationship between membrane potential and the maximum rate of rise of the action potential, (dV/dt)max, and on the recovery kinetics of (dV/dt)max in guinea pig papillary muscles. The steady-state relationships were determined in fibers stimulated at 0.2/sec and depolarized with KCl. Recovery kinetics were determined at various resting membrane potentials by assessing (dV/dt)max in progressively earlier premature action potentials. Lidocaine caused a dose-dependent decrease in (dV/dt)max, shifted the curve defining the steady-state relationship along the voltage axis in the direction of more negative potentials, and slowed the recovery kinetics of (dV/dt)max. Quinidine caused a dose-dependent decrease in (dV/dt)max but did not alter the shape of the curves defining either the steady-state relationship or the recovery kinetics of (dV/dt)max. Both drugs depressed membrane responsiveness as determined in premature action potentials originating from incompletely repolarized fibers. Our study indicates that the mechanisms whereby quinidine and lidocaine influence (dV/dt)max are different. It is possible that this difference may underlie some of the differences in the clinical effects of these two drugs.

  7. 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.

  8. Functional significance of the Frank-Starling mechanism under physiological and pathophysiological conditions.

    Science.gov (United States)

    Jacob, R; Dierberger, B; Kissling, G

    1992-11-01

    The functional significance of the Frank-Starling mechanism under physiological and pathophysiological conditions is discussed, based mainly on animal experiment results (in the dog, pig and rat). The dependence of individual stroke volume on end-diastolic volume can be described adequately using Frank's diagram. This can be illustrated by varying filling pressure (respiratory cycle, vascular tone in the capacitance system, body position, circulating blood volume) and by alterations in the duration of the filling period (heart rate and rhythm, rate of relaxation) and in ventricular compliance (wall thickness, fibrosis; contracture, rigor). The functional importance of the Frank-Starling mechanism lies mainly in adapting left to right ventricular output. During upright physical exercise an increase in end-diastolic volume due to the action of the peripheral muscle pump and increased venous tone can assist in enhancing stroke volume. Reduced contractility leads to a shift of the operating point to the right in the pressure-volume diagram, thus tending to prevent a decrease in stroke volume. However, the consequences of increased circulating blood volume in chronic heart failure are, as a rule, mainly detrimental (congestive symptoms; myocardial component of coronary resistance; cardiac energetics). Reduced contractility results in a flattening of the relation between stroke volume (or stroke work) and end-diastolic volume. Furthermore, the Starling mechanism is prevented from becoming effective if the sarcomere-length reserve is exhausted, or in the presence of inadequate sarcomere extension due to impaired relaxation or reduced distensibility of the ventricular wall. The latter is illustrated using the example of a dilated fibrotic left ventricle from a rat with experimental supravalvular aortic stenosis.

  9. Disruption of cardiac cholinergic neurons enhances susceptibility to ventricular arrhythmias

    Science.gov (United States)

    Jungen, Christiane; Scherschel, Katharina; Eickholt, Christian; Kuklik, Pawel; Klatt, Niklas; Bork, Nadja; Salzbrunn, Tim; Alken, Fares; Angendohr, Stephan; Klene, Christiane; Mester, Janos; Klöcker, Nikolaj; Veldkamp, Marieke W.; Schumacher, Udo; Willems, Stephan; Nikolaev, Viacheslav O.; Meyer, Christian

    2017-01-01

    The parasympathetic nervous system plays an important role in the pathophysiology of atrial fibrillation. Catheter ablation, a minimally invasive procedure deactivating abnormal firing cardiac tissue, is increasingly becoming the therapy of choice for atrial fibrillation. This is inevitably associated with the obliteration of cardiac cholinergic neurons. However, the impact on ventricular electrophysiology is unclear. Here we show that cardiac cholinergic neurons modulate ventricular electrophysiology. Mechanical disruption or pharmacological blockade of parasympathetic innervation shortens ventricular refractory periods, increases the incidence of ventricular arrhythmia and decreases ventricular cAMP levels in murine hearts. Immunohistochemistry confirmed ventricular cholinergic innervation, revealing parasympathetic fibres running from the atria to the ventricles parallel to sympathetic fibres. In humans, catheter ablation of atrial fibrillation, which is accompanied by accidental parasympathetic and concomitant sympathetic denervation, raises the burden of premature ventricular complexes. In summary, our results demonstrate an influence of cardiac cholinergic neurons on the regulation of ventricular function and arrhythmogenesis. PMID:28128201

  10. Takotsubo cardiomyopathy: Pathophysiology,diagnosis and treatment

    Institute of Scientific and Technical Information of China (English)

    Kazuo; Komamura; Miho; Fukui; Toshihiro; Iwasaku; Shinichi; Hirotani; Tohru; Masuyama

    2014-01-01

    In 1990,takotsubo cardiomyopathy(TCM)was first discovered and reported by a Japanese cardiovascular specialist.Since then,this heart disease has gained worldwide acceptance as an independent disease entity.TCM is an important entity that differs from acute myocardial infarction.It occurs more often in postmenopausal elderly women,is characterized by a transient hypokinesis of the left ventricular(LV)apex,and is associated with emotional or physical stress.Wall motion abnormality of the LV apex is generally transient and resolves within a few days to several weeks.Its prognosis is generally good.However,there are some reports of serious TCM complications,including hypotension,heart failure,ventricular rupture,thrombosis involving the LV apex,and torsade de pointes.It has been suggested that coronary spasm,coronary microvascular dysfunction,catecholamine toxicity and myocarditis might contribute to the pathogenesis of TCM.However,its pathophysiology is not clearly understood.

  11. Left ventricular hypertrophy : virtuous intentions, malign consequences

    NARCIS (Netherlands)

    Pokharel, S; Sharma, UC; Pinto, YM

    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 Ca2+ homeostasis, there ar

  12. Programming Pig

    CERN Document Server

    Gates, Alan

    2011-01-01

    This guide is an ideal learning tool and reference for Apache Pig, the open source engine for executing parallel data flows on Hadoop. With Pig, you can batch-process data without having to create a full-fledged application-making it easy for you to experiment with new datasets. Programming Pig introduces new users to Pig, and provides experienced users with comprehensive coverage on key features such as the Pig Latin scripting language, the Grunt shell, and User Defined Functions (UDFs) for extending Pig. If you need to analyze terabytes of data, this book shows you how to do it efficiently

  13. 双苯氟嗪对豚鼠心室肌细胞L-钙电流的影响%Effect of dipfluzine on L-type calcium current in guinea pig ventricular myocytes

    Institute of Scientific and Technical Information of China (English)

    张永健; 李德培; 薛保健; 王永利; 何瑞荣

    2001-01-01

    AIM: To study the effect of dipfluzine (Dip) on L-type calcium current in guinea pig ventricular myocytes.METHODS: Single myocytes were dissociated by enzymatic dissociation method.The current was recorded with the whole-cell configuration of the patch-clamp technique.RESULTS: Dip (0.3-30 μmo l/L)reduced the voltage-dependently activated peak value of ICa-L in a concentration-dependent manner. The characteristics of I-V relationship were not greatly altered by Dip, and the maximal activation voltage of Ica-L in the presence of Dip was not different from that of control.Steady-state activation of Ica-L was not affected markedly, and the half activation potential (V0.5) and the slope factor (κ) in the presence of Dip 3 μmol/L were not markedly different from those of the control. V0.5 value was (-12.8 ±1.7) mV in the control and (-13.2±2.4) mV in the presence of Dip 3 μ mol/L. The κ value was (7.1±0.4) mV in the control and (7.5±0.5) mV in the presence of Dip 3 μmol/L (n=7 cells from 3 hearts, P>0.05). Dip 3 μmol/L markedly shifted the steady-state inactivation curve of ICa-L to the left, and accelerated the voltage-dependent steady-state inactivation of calcium current.V0.5 value was (-19.7±2.4) mV in the control and (-31±6)mV in the presence of Dip 3 μmol/L.The κ value was (3.6±0.3) mV in the control and (1.8±0.2) mV in the presence of Dip 3 μmol/L (n=4cells from 2 hearts, P<0.05). Dip 3 μ mol/L markedly delayed half-recovery time of Ca2 + channel from inactivation from (40±11) to (288±63) ms (n=4, P<0.01).CONCLUSION: Dip mainly acts on the inac ti vated state of L-type calcium channel, accelerates the inactivation of calcium channel, and slows the recovery of calcium channel from inactivated state in guinea pig ventricular myocytes, through which the Ica-L is inhibited.%目的:观察双苯氟嗪(Dip)对豚鼠心室肌细胞L-型钙电流(ICa-L)的影响.方法:酶解法制备单个心室肌细胞.应用全细胞膜片箝技术记录

  14. [Pathophysiology of secondary hyperparathyroidism.

    Science.gov (United States)

    Kawarazaki, Hiroo

    2017-01-01

    Secondary hyperparathyroidism(SHPT)is the result of a compensatory response of the calcium phosphate homeostatic mechanism. Vitamin D deficiency and chronic kidney disease, both representative pathophysiological causes of SHPT, have been related not only to skeletal disorders but also cardiovascular diseases, ADL and QOL. This relates the importance of SHPT as a pathological cause or marker of such states.

  15. Pathophysiology of migraine

    Directory of Open Access Journals (Sweden)

    Peter J Goadsby

    2012-01-01

    Full Text Available Migraine is a common disabling brain disorder whose pathophysiology is now being better understood. The study of anatomy and physiology of pain producing structures in the cranium and the central nervous system modulation of the input have led to the conclusion that migraine involves alterations in the sub-cortical aminergic sensory modulatory systems that influence the brain widely.

  16. Hypertrophic cardiomyopathy: Part 1 - Introduction, pathology and pathophysiology

    Directory of Open Access Journals (Sweden)

    Praveen Kerala Varma

    2014-01-01

    Full Text Available Hypertrophic cardiomyopathy (HCM is the most common genetic cardiovascular disease with many genotype and phenotype variations. Earlier terminologies, hypertrophic obstructive cardiomyopathy and idiopathic hypertrophic sub-aortic stenosis are no longer used to describe this entity. Patients present with or without left ventricular outflow tract (LVOT obstruction. Resting or provocative LVOT obstruction occurs in 70% of patients and is the most common cause of heart failure. The pathology and pathophysiology of HCM includes hypertrophy of the left ventricle with or without right ventricular hypertrophy, systolic anterior motion of mitral valve, dynamic and mechanical LVOT obstruction, mitral regurgitation, diastolic dysfunction, myocardial ischemia, and fibrosis. Thorough understanding of pathology and pathophysiology is important for anesthetic and surgical management.

  17. Obesity: pathophysiology and intervention.

    Science.gov (United States)

    Zhang, Yi; Liu, Ju; Yao, Jianliang; Ji, Gang; Qian, Long; Wang, Jing; Zhang, Guansheng; Tian, Jie; Nie, Yongzhan; Zhang, Yi Edi; Gold, Mark S; Liu, Yijun

    2014-11-18

    Obesity presents a major health hazard of the 21st century. It promotes co-morbid diseases such as heart disease, type 2 diabetes, obstructive sleep apnea, certain types of cancer, and osteoarthritis. Excessive energy intake, physical inactivity, and genetic susceptibility are main causal factors for obesity, while gene mutations, endocrine disorders, medication, or psychiatric illnesses may be underlying causes in some cases. The development and maintenance of obesity may involve central pathophysiological mechanisms such as impaired brain circuit regulation and neuroendocrine hormone dysfunction. Dieting and physical exercise offer the mainstays of obesity treatment, and anti-obesity drugs may be taken in conjunction to reduce appetite or fat absorption. Bariatric surgeries may be performed in overtly obese patients to lessen stomach volume and nutrient absorption, and induce faster satiety. This review provides a summary of literature on the pathophysiological studies of obesity and discusses relevant therapeutic strategies for managing obesity.

  18. Obesity: Pathophysiology and Intervention

    Directory of Open Access Journals (Sweden)

    Yi Zhang

    2014-11-01

    Full Text Available Obesity presents a major health hazard of the 21st century. It promotes co-morbid diseases such as heart disease, type 2 diabetes, obstructive sleep apnea, certain types of cancer, and osteoarthritis. Excessive energy intake, physical inactivity, and genetic susceptibility are main causal factors for obesity, while gene mutations, endocrine disorders, medication, or psychiatric illnesses may be underlying causes in some cases. The development and maintenance of obesity may involve central pathophysiological mechanisms such as impaired brain circuit regulation and neuroendocrine hormone dysfunction. Dieting and physical exercise offer the mainstays of obesity treatment, and anti-obesity drugs may be taken in conjunction to reduce appetite or fat absorption. Bariatric surgeries may be performed in overtly obese patients to lessen stomach volume and nutrient absorption, and induce faster satiety. This review provides a summary of literature on the pathophysiological studies of obesity and discusses relevant therapeutic strategies for managing obesity.

  19. [Pathophysiology of hemorragic shock].

    Science.gov (United States)

    Copotoiu, R; Cinca, E; Collange, O; Levy, F; Mertes, P-M

    2016-11-01

    This review addresses the pathophysiology of hemorrhagic shock, a condition produced by rapid and significant loss of intravascular volume, which may lead to hemodynamic instability, decreases in oxygen delivery, decreased tissue perfusion, cellular hypoxia, organ damage, and death. The initial neuroendocrine response is mainly a sympathetic activation. Haemorrhagic shock is associated altered microcirculatory permeability and visceral injury. It is also responsible for a complex inflammatory response associated with hemostasis alteration. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  20. Pathophysiology of cancer cachexia

    OpenAIRE

    Younes Riad N.; Noguchi Yoshikazu

    2000-01-01

    Cancer cachexia is a frequent complication observed in patients with malignant tumors. Although several decades have passed since the first focus on the metabolic dysfunction's associated with cancer, few effective therapeutic interventions have been successfully introduced into the medical armamentarium. The present study thoroughly reviews the basic pathophysiology of cancer cachexia and the treatment options already investigated in that field. Experimental and clinical studies were evaluat...

  1. Physiology and Pathophysiology of Iron Cardiomyopathy in Thalassemia

    OpenAIRE

    2005-01-01

    Iron cardiomyopathy remains the leading cause of death in patients with thalassemia major. Magnetic resonance imaging (MRI) is ideally suited for monitoring thalassemia patients because it can detect cardiac and liver iron burdens as well as accurately measure left ventricular dimensions and function. However, patients with thalassemia have unique physiology that alters their normative data. In this article, we review the physiology and pathophysiology of thalassemic heart disease as well as ...

  2. Premature Ventricular Contractions (PVCs)

    Science.gov (United States)

    Diseases and Conditions Premature ventricular contractions (PVCs) By Mayo Clinic Staff Premature ventricular contractions (PVCs) are extra, abnormal heartbeats that begin in one of your heart's two ...

  3. Proposed Pathophysiologic Framework to Explain Some ...

    Science.gov (United States)

    The paper proposes a pathophysiologic framework to explain the well-established epidemiological association between exposure to ambient air particle pollution and premature cardiovascular mortality, and offers insights into public health solutions that extend beyond regularory environmental protections to actions that can be taken by individuals, public health officials, healthcare professionals, city and regional planners, local and state governmental officials and all those who possess the capacity to improve cardiovascular health within the popula­tion.The foundation of the framework rests on the contribution of traditional cardiovascular risk factors acting alone and in concert with long-term exposures to air pollutants to create a conditional susceptibility for clinical vascular events, such as myocardial ischemia and infarction; stroke and lethal ventricular arrhythmias. The conceprual framework focuses on the fact that short-term exposures to ambient air particulate matter (PM) are associated with vascular thrombosis (acute coronary syndrome. stroke, deep venous thrombosis. and pulmonary embolism ) and electrical dysfunction (ventricular arrhythmia); and that individuals having prevalent heart disease are at greatest risk. Moreover, exposure is concomitant with changes in autonomic nervous system balance, systemic in­flammation, and prothrombotic/anti-thrombotic and profibrinolytic-antifibrinolytic balance.Thus, a comprehensive solution to the problem o

  4. Arrhythmogenic right ventricular cardiomyopathy/dysplasia: an updated imaging approach.

    Science.gov (United States)

    Zimmerman, Stefan L

    2015-02-01

    Arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) is a rare inherited cardiomyopathy characterized by fibrofatty replacement of the right ventricular myocardium and risk of sudden death from ventricular tachyarrhythmias. Cardiac magnetic resonance (MR) imaging plays an important role in the diagnostic evaluation of patients and family members suspected of having ARVC/D. This article discusses the epidemiology and pathophysiology of ARVC/D, reviews typical MR imaging findings and diagnostic criteria, and summarizes potential pitfalls in the MR imaging evaluation of patients suspected of having ARVC/D.

  5. Effects of potassium channel activators on transient inward current in guinea pig ventricular myocytes%钾通道激动剂对豚鼠心室肌动作电位及瞬间内向电流作用机制的探讨

    Institute of Scientific and Technical Information of China (English)

    张宏艳; 范崇济; 李小梅; 邢淑华; 潘永祜; 陈静; 杨楠; 陈朝晖

    2008-01-01

    Objective To investigate the mechanism of ATP-sensitive potassium channel(KATP) activator cromakaliam(CRK)on action potentials and transient inward current(Iti)in isolated guinea pig papillary and ventricular myocytes and to explore the mechanisms of effects of Iti and KATP treatment in idiopathic ventricular tachycardia.Methods The whole-cell patch clamp recording technique was used to detect the action potentials and Iti and KATP current alterations during the stimulated and triggered activity. Myocytes were isolated from guinea pig ventricle by enzyme digestion.The experiment was divided into four groups:(1)Control;(2)Control+Ouabain;(3)Control+CRK;(4)Control+Ouabain+CRK.(5) Control+Ouabain+CRK+glibenclamide(GLB).The action potential of guinea pig papillary muscules was measured by using standard microelectrode.The parameters in the experimant incluced the amplitude (APA),resting potentials(RP),action potentials duration(APD),as well as maximum rise of the action potential(Vmax).Results (1)When the guinea pig ventricular papillary myocytes were pretreated with Ouabain 0.5~mol/L,APD prolonged significantly,especially APD20,APD50,APD90.Delayed after depotorazion(DAD)and triggered activity were elicited.Iti currents and DAD as well as triggered activity increased.Iti current was(126.9±10.8)pA,lagT(1173.0±70.9)ms(n=10,P<0.01).(2)When guinea pig ventricular myocytes were pretreated with CRK(10 umol/L),APD was shortened and the amplitude of DAD was lowered.The coupling time in CRK group was significantly prolonged compared with Ouabain group(n=10,P<0.01).(3)CRK 50umol/L pretreatment of the ventricular myocytes led to an increase of KATP up to(342±89)pA,which was statistically significant as compared with the control group(P<0.01).ATP-sensitive potassium channel blocker glibeclamide(10umol/L)could antagonize the effects of CRK on APD and Iti currents.Conciusion CRK might reduce the toxic effect of Ouabain on cardiomyocytes,shorten APD,terminate DAD and trigger

  6. Reform in teaching preclinical pathophysiology.

    Science.gov (United States)

    Li, Yong-Yu; Li, Kun; Yao, Hong; Xu, Xiao-Juan; Cai, Qiao-Lin

    2015-12-01

    Pathophysiology is a scientific discipline that studies the onset and progression of pathological conditions and diseases, and pathophysiology is one of the core courses in most preclinical medical curricula. In China, most medical schools house a Department of Pathophysiology, in contrast to medical schools in many developed countries. The staff in Chinese Departments of Pathophysiology generally consists of full-time instructors or lecturers who teach medical students. These lecturers are sometimes lacking in clinic knowledge and experiences. To overcome this, in recent years, we have been trying to bring new trends in teaching pathophysiology into our curriculum. Our purpose in writing this article was to share our experiences with our colleagues and peers worldwide in the hope that the insights we have gained in pathophysiology teaching will be of some value to educators who advocate teaching reform in medical schools.

  7. Efeitos hemodinâmicos da sobrecarga ventricular direita aguda experimental Efectos hemodinámicos de la sobrecarga ventricular derecha aguda experimental Hemodynamic effects of experimental acute right ventricular overload

    Directory of Open Access Journals (Sweden)

    Flávio Brito Filho

    2011-04-01

    el estudio, siendo divididos en 4 grupos: uno control, no sometido a la oclusión vascular pulmonar, y tres de sobrecarga ventricular derecha sometidos a la oclusión de las siguientes arterias pulmonares: SVD1 (arteria pulmonar izquierda; SVD2 (arteria pulmonar izquierda y del lóbulo inferior derecho y SVD3 (arteria pulmonar izquierda, del lóbulo inferior derecho y del lóbulo mediastinal, obstruyendo la vasculatura pulmonar en 42, 76 y 82,0% respectivamente. Variables de hemodinámica fueron medidas cada 15 minutos durante una hora del estudio. En el análisis estadístico, fueron utilizados ajustes de modelos lineares mixtos con estructura de variancias y covariancias. RESULTADOS:En las comparaciones intergrupales, hubo aumento significativo de la frecuencia cardíaca (p = 0,004, presión arterial pulmonar media (p = 0,001 y presión capilar pulmonar (p BACKGROUND: Acute right ventricular overload is associated with high morbidity and mortality clinical situations such as: extensive lung resection, pulmonary thromboembolism, lung transplantation and high altitude pulmonary edema. Some points of its pathophysiology remain unclear. OBJECTIVE: To assess the hemodynamic effects of experimental acute right ventricular overload in pigs. METHODS: Right ventricular overload was induced through the occlusion of the pulmonary arteries using ligationss. Twenty pigs were used in the study, divided into 04 groups: one control group not subject to pulmonary vascular occlusion, and three right ventricular overload groups subject to occlusion of the following pulmonary arteries: SVD1 (left pulmonary artery; SVD2 (left pulmonary artery and right lower lobe and SVD3 (left pulmonary artery, right lower lobe and mediastinal lobe, obstructing the pulmonary vasculature in 42, 76 and 82.0% respectively. Hemodynamic variables were measured every 15 minutes during one hour of study. The statistical analysis employed mixed linear models with variance and covariance structures. RESULTS

  8. Ventricular torsional relation to ventricular fiber arrangement

    CERN Document Server

    Ranjbar, Saeed; Meybodi, Mahmood Emami

    2014-01-01

    Left ventricular torsion from helically oriented myofibers is a key parameter of cardiac performance. Physicians observing heart motion on echocardiograms, during cardiac catheterization, or in the operating room, are impressed by the twisting or rotary motion of the left ventricle during systole. Conceptually, the heart has been treated as a pressure chamber. The rotary or torsional deformation has been poorly understood by basic scientists and has lacked clinical relevance. The aim of this paper attempts to discuss about this question: Is ventricular twisting related to ventricular fiber arrangement? That is dependent to an assumed model of the left ventricular structure.

  9. Vagal control of cardiac electrical activity and wall motion during ventricular fibrillation in large animals.

    Science.gov (United States)

    Naggar, Isaac; Nakase, Ko; Lazar, Jason; Salciccioli, Louis; Selesnick, Ivan; Stewart, Mark

    2014-07-01

    Vagal inputs control pacemaking and conduction systems in the heart. Anatomical evidence suggests a direct ventricular action, but functional evidence that separates direct and indirect (via the conduction system) vagal actions is less well established. We studied vagus nerve stimulation (VNS) during sinus rhythm and ventricular fibrillation (VF) in pigs and sheep to determine: 1) the range of unilateral and bilateral actions (inotropic and chronotropic) and 2) whether VNS alters left ventricular motion and/or electrical activity during VF, a model of abnormal electrical conduction of the left ventricle that excludes sinus and atrioventricular nodal function. Adult pigs (N=8) and sheep (N=10) were anesthetized with urethane and mechanically ventilated. VNS was performed in animals at 1, 2, 5, 10, 20, 50, and 100Hz for 20s. VF was induced with direct current to the ventricles or occlusion of the left anterior descending coronary artery. In 4 pigs and 3 sheep, left ventricular wall motion was assessed from endocardial excursion in epicardial echocardiography. In sheep and pigs, the best frequency among those tested for VNS during sinus rhythm to produce sustained electrical and mechanical ventricular standstill was 50Hz for unilateral or bilateral stimulation. When applied during VF, bilateral VNS increased the variability of the dominant VF frequency, indicating a direct impact on the excitability of ventricular myocytes, and decreased endocardial excursion by more than 50% during VF. We conclude that the vagus nerve directly modulates left ventricular function independently from its effects on the conduction system.

  10. Pathophysiology of nasal congestion

    Directory of Open Access Journals (Sweden)

    Robert M Naclerio

    2010-02-01

    Full Text Available Robert M Naclerio1, Claus Bachert2, James N Baraniuk31University of Chicago, Department of Surgery, Section of Otolaryngology – Head and Neck Surgery, Chicago, Illinois, USA; 2University of Ghent, Ghent, Belgium; 3Georgetown University, Washington, DC, USAAbstract: Nasal congestion is a common symptom in rhinitis (both allergic and nonallergic, rhinosinusitis and nasal polyposis. Congestion can also be caused by physical obstruction of nasal passages and/or modulation of sensory perception. Mucosal inflammation underlies many of the specific and interrelated factors that contribute to nasal congestion, as well as other symptoms of both allergic rhinitis and rhinosinusitis. A wide range of biologically active agents (eg, histamine, tumor necrosis factor-α, interleukins, cell adhesion molecules and cell types contribute to inflammation, which can manifest as venous engorgement, increased nasal secretions and tissue swelling/edema, ultimately leading to impaired airflow and the sensation of nasal congestion. Inflammation-induced changes in the properties of sensory afferents (eg, expression of peptides and receptors that innervate the nose can also contribute to altered sensory perception, which may result in a subjective feeling of congestion. Increased understanding of the mechanisms underlying inflammation can facilitate improved treatment selection and the development of new therapies for congestion.Keywords: allergic rhinitis, congestion, obstruction, pathophysiology, rhinosinusitis

  11. Hypertension: physiology and pathophysiology.

    Science.gov (United States)

    Hall, John E; Granger, Joey P; do Carmo, Jussara M; da Silva, Alexandre A; Dubinion, John; George, Eric; Hamza, Shereen; Speed, Joshua; Hall, Michael E

    2012-10-01

    Despite major advances in understanding the pathophysiology of hypertension and availability of effective and safe antihypertensive drugs, suboptimal blood pressure (BP) control is still the most important risk factor for cardiovascular mortality and is globally responsible for more than 7 million deaths annually. Short-term and long-term BP regulation involve the integrated actions of multiple cardiovascular, renal, neural, endocrine, and local tissue control systems. Clinical and experimental observations strongly support a central role for the kidneys in the long-term regulation of BP, and abnormal renal-pressure natriuresis is present in all forms of chronic hypertension. Impaired renal-pressure natriuresis and chronic hypertension can be caused by intrarenal or extrarenal factors that reduce glomerular filtration rate or increase renal tubular reabsorption of salt and water; these factors include excessive activation of the renin-angiotensin-aldosterone and sympathetic nervous systems, increased formation of reactive oxygen species, endothelin, and inflammatory cytokines, or decreased synthesis of nitric oxide and various natriuretic factors. In human primary (essential) hypertension, the precise causes of impaired renal function are not completely understood, although excessive weight gain and dietary factors appear to play a major role since hypertension is rare in nonobese hunter-gathers living in nonindustrialized societies. Recent advances in genetics offer opportunities to discover gene-environment interactions that may also contribute to hypertension, although success thus far has been limited mainly to identification of rare monogenic forms of hypertension. © 2012 American Physiological Society

  12. [Sickle cell pathophysiology].

    Science.gov (United States)

    Renaudier, P

    2014-11-01

    Sickle cell disease is associated with the inversion of one base pair (A = T → A = T). The sixth codon of the beta globin chain [GAA] becomes [GTA]. Accordingly, the sixth amino acid (glutamic acid, negatively charged) is replaced by valine, hydrophobic. A hydrophobic site is present on the outside of the HbS β chain. This incurs a hydrophobic bond with the phenylalanine in position 85 and leucine in position 88, in which outsource deoxy haemoglobin. Therefore, it creates a HbS polymer that deforms the red blood cell and causes vaso-occlusive crisis in the capillary venous pole. In this conventional design, the roles are added to the nitrogen monoxide and vascular tone, the increase in adhesion of red blood cells to the endothelium damage caused by red blood cells HbS: dehydration, senescence, formation of microvesicles. If these advances in our understanding of the pathophysiology have not yet had a clinical application, they will happen one day. It is therefore particularly important to pursue in France the network structure of sickle cell disease with a view to set up multicenter trials when the day comes.

  13. The pathophysiology of concussion.

    Science.gov (United States)

    Signoretti, Stefano; Lazzarino, Giuseppe; Tavazzi, Barbara; Vagnozzi, Roberto

    2011-10-01

    Concussion is defined as a biomechanically induced brain injury characterized by the absence of gross anatomic lesions. Early and late clinical symptoms, including impairments of memory and attention, headache, and alteration of mental status, are the result of neuronal dysfunction mostly caused by functional rather than structural abnormalities. The mechanical insult initiates a complex cascade of metabolic events leading to perturbation of delicate neuronal homeostatic balances. Starting from neurotoxicity, energetic metabolism disturbance caused by the initial mitochondrial dysfunction seems to be the main biochemical explanation for most postconcussive signs and symptoms. Furthermore, concussed cells enter a peculiar state of vulnerability, and if a second concussion is sustained while they are in this state, they may be irreversibly damaged by the occurrence of swelling. This condition of concussion-induced brain vulnerability is the basic pathophysiology of the second impact syndrome. N-acetylaspartate, a brain-specific compound representative of neuronal metabolic wellness, is proving a valid surrogate marker of the post-traumatic biochemical damage, and its utility in monitoring the recovery of the aforementioned "functional" disturbance as a concussion marker is emerging, because it is easily detectable through proton magnetic resonance spectroscopy. Copyright © 2011 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

  14. Ventricular septal defect (image)

    Science.gov (United States)

    Ventricular septal defect is a congenital defect of the heart, that occurs as an abnormal opening in ... wall that separates the right and left ventricles. Ventricular septal defect may also be associated with other ...

  15. Role of left ventricular twist mechanics in cardiomyopathies, dance of the helices

    Institute of Scientific and Technical Information of China (English)

    Floris; Kauer; Marcel; Leonard; Geleijnse; Bastiaan; Martijn; van; Dalen

    2015-01-01

    Left ventricular twist is an essential part of left ventricular function. Nevertheless, knowledge is limited in "the cardiology community" as it comes to twist mechanics. Fortunately the development of speckle tracking echocardiography, allowing accurate, reproducible and rapid bedside assessment of left ventricular twist, has boosted the interest in this important mechanical aspect of left ventricular deformation. Although the fundamental physiological role of left ventricular twist is undisputable, the clinical relevance of assessment of left ventricular twist in cardiomyopathies still needs to be established. The fact remains; analysis of left ventricular twist mechanics has already provided substantial pathophysiological understanding on a comprehensive variety of cardiomyopathies. It has become clear that increased left ventricular twist in for example hypertrophic cardiomyopathy may be an early sign of subendocardial(microvascular) dysfunction. Furthermore, decreased left ventricular twist may be caused by left ventricular dilatation or an extensive myocardial scar. Finally, the detection of left ventricular rigid body rotation in noncompaction cardiomyopathy may provide an indispensible method to objectively confirm this difficult diagnosis. All this endorses the value of left ventricular twist in the field of cardiomyopathies and may further encourage the implementation of left ventricular twist parameters in the "diagnostic toolbox" for cardiomyopathies.

  16. 肾上腺素对离体豚鼠左心室流出道组织自律性电活动的影响%Electrophysiological Effects of Epinephrine on Pacemaker Cells in Guinea-pig Left Ventricular Outflow Tract

    Institute of Scientific and Technical Information of China (English)

    陈立锋; 徐涛; 范凌; 陈少峰; 孙琳; 尹万斌; 赵兰平

    2009-01-01

    Objective:To explore the effects of epinephrine(E)on spontaneous slow action potentials(APs)of guinea-pig left ventricular outflow tract cells.Methods:By using standard intracellular microelectrode technique to record APs,E was used to investigate the electrophysiological features of left ventricular outflow tract cells.Electrophysiological parameters examined were:maximal diastolic potential(MDP),amplitude of action potential(APA),maximal rate of depolarization(Vmax),velocity of diastolic depolarization(VDD),rate of pacemaker firing(RPF),50% and 90% of duration of action potential(APD50 and APD90).Results:The results obtained were as follows:Application of 100μmol/L E resulted in a significant increase in VDD(P<0.05),RPF(P<0.01),APA(P<0.05),MDP(P<0.05)and Vmax(P<0.05);a notable shorteness in and APD90(P<0.01)in the pacemaker cells.Conclusion:These results suggested that E should excite the pacemaker cells of left ventricular outflow tract.%目的:观察肾上腺素(E)对离体豚鼠左心室流出道组织自发慢反应电位的影响.方法:采用标准玻璃微电极细胞内记录技术,观察E对离体豚鼠左心室流出道组织自发慢反应电位的影响.观测指标有:最大舒张电位(MDP),动作电位幅度(APA),0期最大除极速度(Vmax),4期自动除极速度(VDD),自发放电频率(RPF),复极50%和90%时间(APD50、APD90).结果:用100μmol/L E灌流,豚鼠左心室流出道自律组织动作电位APA明显增大(P<0.01),Vmax明显增快(P<0.05),MDP显著增大(P<0.05),APD90显著缩短(P<0.01);RPF明显增快(P<0.01),VDD明显加快(P<0.05).结论:E对左心室流出道组织自律细胞有兴奋作用.

  17. Pathophysiology of cancer cachexia

    Directory of Open Access Journals (Sweden)

    Riad N. Younes

    2000-10-01

    Full Text Available Cancer cachexia is a frequent complication observed in patients with malignant tumors. Although several decades have passed since the first focus on the metabolic dysfunction's associated with cancer, few effective therapeutic interventions have been successfully introduced into the medical armamentarium. The present study thoroughly reviews the basic pathophysiology of cancer cachexia and the treatment options already investigated in that field. Experimental and clinical studies were evaluated individually in order to clarify the intricate alterations observed in tumor-bearing patients. The difficulties in introducing sound and effective nutritional support or metabolic manipulation to reverse cancer cachexia are outlined in this review.A caquexia é uma complicação freqüentemente observada em pacientes portadores de tumores malignos. Apesar de várias décadas transcorrerem desde a descrição inicial das disfunções metabólicas associadas ao câncer, poucas medidas terapêuticas foram induzidas com sucesso na prática médica. O presente estudo apresenta uma revisão detalhada da fisiopatologia básica da caquexia em câncer, e as opções terapêuticas desenvolvidas nesta área. Estudos experimentais, assim como clínicos, são avaliados individualmente para esclarecer as alterações complexas observadas em pacientes portadores de tumores. As dificuldades encontradas para introduzir manipulações metabólicas e terapias de suporte nutricional eficientes são discutidas nesta revisão.

  18. [Pathophysiology of urticaria].

    Science.gov (United States)

    Nosbaum, A; Augey, F; Nicolas, J-F; Bérard, F

    2014-11-01

    Urticaria is a dermal edema resulting from vascular dilatation and leakage of fluid into the skin in response to molecules released from mast cells. The major mediator responsible for urticaria is histamine. However, the clinical spectrum and pattern of lesions indicate that other molecules, including prostaglandins, leukotrienes, cytokines, and chemokines, produced at different times after mast cell activation contribute to the polymorphism of this symptom and the variable evolution of this disease. It is a common practice to distinguish immunological and nonimmunological urticaria. Immunological urticaria is a hypersensitivity reaction mediated by antibodies and/or T-cells that results in mast cell activation. Although immunoglobulin (Ig) E-mediated type I hypersensitivity (HS) was long postulated to be the major immunological pathway associated with mast cell activation, interaction between IgEbound mast cells and allergens is unlikely to be the mechanism by which urticaria develops in most patients. It is now well established that urticaria may result from the binding of IgG auto-antibodies to IgE and/or to the receptor for IgE molecules on mast cells, thus corresponding to a type II HS reaction. These auto-immune urticarias represent up to 50 % of patients with chronic urticaria. Mast cell activation can also result from type III HS through the binding of circulating immune complexes to mast cell-expressing Fc receptors for IgG and IgM. Finally, under certain circumstances, T-cells can induce activation of mast cells, as well as histamine release (type IV HS). Nonimmunological urticarias result from mast cell activation through membrane receptors involved in innate immunity (e.g., complement, Toll-like, cytokine/chemokine, opioid) or by direct toxicity of xenobiotics (haptens, drugs). In conclusion, urticaria may result from different pathophysiological mechanisms that explain the great heterogeneity of clinical symptoms and the variable responses to treatment.

  19. Histotripsy for Pediatric Cardiac Applications: In Vivo Neonatal Pig Model

    Science.gov (United States)

    Miller, Ryan M.; Owens, Gabe; Ensing, Gregory; Ludomirsky, Achiau; Cain, Charles; Xu, Zhen

    2010-03-01

    This study investigated the in vivo feasibility of using histotripsy to non-invasively create a flow channel between the ventricles by generating a perforation of the ventricular septum, clinically referred to as a ventricular septum defect (VSD). The overall goal is to develop a non-invasive procedure to aid in the treatment of neonatal patients with complex congenital heart diseases such as Hypoplastic Left Heart Syndrome (HLHS). Histotripsy is a therapeutic ultrasound technique that produces mechanical fractionation of soft tissue through controlled cavitation. The study was conducted in a live and intact neonatal pig model. The ventricular septum in the neonatal pig heart was treated with histotripsy delivered by a spherically focused 1 MHz transducer positioned outside the chest wall. Histotripsy treatment was applied using 5-cycle ultrasound pulses at 1 kHz pulse repetition frequency with 12-18 MPa peak negative pressure. The treatment was guided and monitored with ultrasound imaging. In all nine subjects treated, a bubble cloud was generated on the ventricular septum using histotripsy, and visualized with ultrasound imaging. Within 20 seconds to 4 minutes following the initiation of a bubble cloud, a VSD was created in all nine pigs and confirmed by the detection of blood flow through the ventricular septum with color Doppler ultrasound. Gross morphology and histology on all hearts showed a demarcated perforation in the ventricular septum. This study shows that a VSD can be created in an intact neonatal animal using extracorporeal histotripsy under real-time ultrasound guidance.

  20. Physiology and pathophysiology of iron cardiomyopathy in thalassemia.

    Science.gov (United States)

    Wood, John C; Enriquez, Cathleen; Ghugre, Nilesh; Otto-Duessel, Maya; Aguilar, Michelle; Nelson, Marvin D; Moats, Rex; Coates, Thomas D

    2005-01-01

    Iron cardiomyopathy remains the leading cause of death in patients with thalassemia major. Magnetic resonance imaging (MRI) is ideally suited for monitoring thalassemia patients because it can detect cardiac and liver iron burdens as well as accurately measure left ventricular dimensions and function. However, patients with thalassemia have unique physiology that alters their normative data. In this article, we review the physiology and pathophysiology of thalassemic heart disease as well as the use of MRI to monitor it. Despite regular transfusions, thalassemia major patients have larger ventricular volumes, higher cardiac outputs, and lower total vascular resistances than published data for healthy control subjects; these hemodynamic findings are consistent with chronic anemia. Cardiac iron overload increases the relative risk of further dilation, arrhythmias, and decreased systolic function. However, many patients are asymptomatic despite heavy cardiac burdens. We explore possible mechanisms behind cardiac iron-function relationships and relate these mechanisms to clinical observations.

  1. Transient stress cardiomyopathies in the elderly: Clinical & Pathophysiologic considerations

    Institute of Scientific and Technical Information of China (English)

    Michael A Chen

    2012-01-01

    Transient stress-induced cardiomyopathies have been increasingly recognized and while rare,they tend to affect elderly women more than other demographic groups.One type,often called tako-tsubo cardiomyopathy (TTC),is typically triggered by significant emotional or physical stress and is associated with chest pain,electrocardiogram (ECG) changes and abnormal cardiac enzymes.Significant left ventricular regional wall motion abnormalities usually include an akinetic "ballooning" apex with normal or hyperdynamic function of the base.A second type,often called neurogenic stunned myocardium,typically associated with subarachnoid hemorrhage,also usually presents with ECG changes and positive enzymes,but the typical wall motion abnormalities seen include normal basal and apical left ventricular contraction with akinesis of the mid-cavity in a circumferential fashion.The pathophysiology,clinical care and typical courses,are reviewed.

  2. Carbachol augments Na/Ca exchange current via M2 muscarinic receptors in guinea pig ventricular myocytes%氨甲酰胆碱通过M2毒蕈碱受体增加豚鼠心肌细胞钠钙交换电流

    Institute of Scientific and Technical Information of China (English)

    崔香丽; 陈还珍; 武冬梅; 吴博威

    2004-01-01

    Stimulation of cardiac mAChRs by carbachol (CCh) produces a biphasic inotropic response. The mechanisms of the positive inotropic response by higher concentration of CCh appear to be paradoxical. This article was aimed to study the mechanism of the positive inotropic effect of CCh in guinea pig ventricular myocytes. The effects of CCh on L-type calcium current (ICa) and Na/Ca exchange current (INa/Ca) were observed in voltage-clamped guinea pig ventricular myocytes by using Axon 200A amplifier. The results showed that CCh (100 μmol/L) increased both forword mode and reverse mode INa/Ca from (1.2±0.1) pA/pF to (2.0±0.3) pA/pF for forward mode (P<0.01) and from (1.3+0.5) pA/pF to (2.1+0.8) pA/pF for reverse mode (P<0.01), respectively. CCh had no effect on ICa. The stimulating effect of CCh on INa/Ca could be blocked by application of atropine, a nonselective blocker of muscarinic receptors,which means that the stimulating effect of CCh is through the activation of muscarinic receptors. We made a further study by using methoctramine, a selective antagonist of M2 muscarinic receptors. It completely abolished INa/Ca induced by 100 μmol/L CCh, indicating that the effect of CCh on INa/Ca was mediated by M2 muscarinic receptors. It is generally accepted that contraction in cardiac myocytes results from elevation of intracellular Ca2+ concentration. Ca2+ enters the cells through two pathways: L-type Ca2+ channels and, less importantly, reverse mode Na/Ca exchange. The calcium influx via both pathways promotes the contraction of cardiac myocytes.Because CCh had no effect on L-type Ca2+ current, the increase in Na/Ca exchange current might be the main factor in the positive inotropism of CCh. These results suggest that the positive inotropic effect of CCh in guinea pig heart is through stimulation of Na/Ca exchange and is mediated by M2 muscarinic receptors.%本文旨在研究氨甲酰胆碱(carbachol,CCh)对豚鼠心肌的正性变力性机制.用Axon200A膜片钳

  3. LUPUS ANTICOAGULANTS: PATHOPHYSIOLOGY, CLINICAL AND ...

    African Journals Online (AJOL)

    2003-11-02

    Nov 2, 2003 ... clinical, laboratory, pathophysiology and management. Only data relevant to the ... pulmonary hypertension, heparin related ... anticoagulant effect of beta 2 factor Xa. .... with severe valvular heart disease in patients with and.

  4. [Functional pathophysiology of consciousness].

    Science.gov (United States)

    Jellinger, Kurt A

    2009-01-01

    from important somatic and sensory pathways and acts as a control system of neuronal activities of the cerebral cortex. The principal function of the ARAS is to focus our alertness on specific stimuli or internal processes, which run via complex neuronal cell groups and numerous neurotransmitters that influence various aspects of consciousness and wakefulness. Stimulation of the ARAS produces an arousal reaction as the electric correlate of consciousness; its destruction causes coma and related states. The highest level are cortical (prefrontal and association) networks for recognition, motor activity, longterm memory and attention, the left hemisphere being considered as the dominant one. Different levels of consciousness are distinguished: 1. hyperalertness, 2. alertness (normal state of wakefulness), 3. somnolence or lethargy, 4. obtundation with tendency to fall asleep, 5. stupor, 6. coma and its subtypes, like akinetic mutism, apallic syndrome or persistent vegative state, locked-in syndrome, delirium, and catatonia. They are caused by damages in various functional levels of the brain, by psychogenic factors or experimentally, and are accompanied by characteristic neurological and psychiatric disorders. The relevant morphological lesions can be detected by electrophysiological and imaging studies. The bases of functional anatomy and pathophysiology of consciousness, its cognitive aspects and its major disorders, their causes and functional substrates with reference to sleep and both spontaneous and iatrogenic disorders of consciousness are critically summarized.

  5. The Downside of Right Ventricular Apical Pacing

    Directory of Open Access Journals (Sweden)

    Andrew Brenyo, MD

    2012-05-01

    Full Text Available The right ventricular (RV apex has been the standard pacing site since the development of implantable pacemaker technology. Although RV pacing was initially only utilized for the treatment of severe bradyarrhythmias usually due to complete heart block, today the indications for and implantation of RV pacing devices is dramatically larger. Recently, the adverse effects of chronic RV apical pacing have been described including an increased risk of heart failure and death. This review details the detrimental effects of RV apical pacing and their shared hemodynamic pathophysiology. In particular, the role of RV apical pacing induced ventricular dyssynchrony is highlighted with a specific focus on differential outcome based upon QRS morphology at implant.

  6. 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

    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

  7. [Pathophysiology of hypertension: what's new?].

    Science.gov (United States)

    Büchner, Nikolaus; Vonend, Oliver; Rump, Lars Christian

    2006-06-01

    The pathophysiology of primary hypertension is still unresolved and appears more complex than ever. It is beyond the scope of this article to review all new scientific developments in this field. On clinical grounds, hypertension is divided into primary and secondary forms. Here, the authors discuss the pathophysiology of hypertension associated with three common disease entities showing a large overlap with primary hypertension: chronic kidney disease (CKD), obstructive sleep apnea (OSA), and hyperaldosteronism. Especially in CKD and OSA, the activation of the sympathetic nervous system plays a crucial role. It is the authors' belief that hypertension due to these three diseases is more common than previously appreciated and may account for about 20% of the hypertensive population. The knowledge of the underlying pathophysiology allows early diagnosis and guides optimal treatment of these hypertensive patients.

  8. Sepsis pathophysiology and anesthetic consideration.

    Science.gov (United States)

    Yuki, Koichi; Murakami, Naoka

    2015-01-01

    Sepsis remains to be a significant health care issue associated with high mortality and healthcare cost, despite the extensive effort to better understand the pathophysiology of the sepsis. Recently updated clinical guideline for severe sepsis and septic shock, "Surviving Sepsis Campaign 2012", emphasizes the importance of early goal-directed therapy, which can be implemented in intraoperative management of sepsis patients. Herein, we review the updates of current guideline and discuss its application to anesthesic management. Furthermore, we review the recent advance in knowledge of sepsis pathophysiology, focusing on immune modulation, which may lead to new clinical therapeutic approach to sepsis.

  9. Adverse ventricular-ventricular interactions in right ventricular pressure load: Insights from pediatric pulmonary hypertension versus pulmonary stenosis.

    Science.gov (United States)

    Driessen, Mieke M P; Hui, Wei; Bijnens, Bart H; Dragulescu, Andreea; Mertens, Luc; Meijboom, Folkert J; Friedberg, Mark K

    2016-06-01

    Right ventricular (RV) pressure overload has a vastly different clinical course in children with idiopathic pulmonary arterial hypertension (iPAH) than in children with pulmonary stenosis (PS). While RV function is well recognized as a key prognostic factor in iPAH, adverse ventricular-ventricular interactions and LV dysfunction are less well characterized and the pathophysiology is incompletely understood. We compared ventricular-ventricular interactions as hypothesized drivers of biventricular dysfunction in pediatric iPAH versus PS Eighteen iPAH, 16 PS patients and 18 age- and size-matched controls were retrospectively studied. Cardiac cycle events were measured by M-mode and Doppler echocardiography. Measurements were compared between groups using ANOVA with post hoc Dunnet's or ANCOVA including RV systolic pressure (RVSP; iPAH 96.8 ± 25.4 mmHg vs. PS 75.4 ± 18.9 mmHg; P = 0.011) as a covariate. RV-free wall thickening was prolonged in iPAH versus PS, extending beyond pulmonary valve closure (638 ± 76 msec vs. 562 ± 76 msec vs. 473 ± 59 msec controls). LV and RV isovolumetric relaxation were prolonged in iPAH (P < 0.001; LV 102.8 ± 24.1 msec vs. 63.1 ± 13.7 msec; RV 95 [61-165] vs. 28 [0-43]), associated with adverse septal kinetics; characterized by rightward displacement in early systole and leftward displacement in late RV systole (i.e., early LV diastole). Early LV diastolic filling was decreased in iPAH (73 ± 15.9 vs. PS 87.4 ± 14.4 vs. controls 95.8 ± 12.5 cm/sec; P = 0.004). Prolonged RVFW thickening, prolonged RVFW isovolumetric times, and profound septal dyskinesia are associated with interventricular mechanical discoordination and decreased early LV filling in pediatric iPAH much more than PS These adverse mechanics affect systolic and diastolic biventricular efficiency in iPAH and may form the basis for worse clinical outcomes. We used clinically derived data to study the pathophysiology of ventricular-ventricular

  10. Electrophysiological effects of lidocaine on myocardial tissue in guinea-pig left ventricular outflow tract under conditions of hypoxia, acidosis and treatment with epinephrine%利多卡因对低氧、酸中毒及肾上腺素条件下豚鼠左心室流出道心肌组织电活动的影响

    Institute of Scientific and Technical Information of China (English)

    赵兰平; 王雪芳; 杜会博; 薛淑芳; 陈彦静

    2013-01-01

    AIM; To study the electrophysiological effects of lidocaine on the myocardial tissue in guinea-pig left ventricular outflow tract under the conditions of hypoxia, acidosis and treatment with epinephrine. METHODS: The action potentials of pacemaker cells in guinea-pig left ventricular outflow tract were recorded by conventional technique with intracellular microelectrodes. The effects of lidocaine on the spontaneous slow response potentials were investigated under the conditions of hypoxia, acidosis and treatment with epinephrine (EPI). RESULTS: Lidocaine markedly decreased the rate of pacemaker firing ( RPF) , the velocity of diastolic depolarization ( VDD) , the maximal rate of depolarization ( Vmax), the maximal diastolic potential (MDP) and the amplitude of action potential ( APA). Lidocaine also shortened the 50% and 80% of duration of action potential (APD50 and APD80). At the concentrations from 0.1 μmol/L to 10 μmol/L, the effects of lidocaine were more significant. Under the condition of hypoxia and perfusion with deprived glucose content for 15 min, VDD, RPF, Vmax, MDP and APA significantly decreased, and APD50 notably shortened. Under the condition of hypoxia, lidocaine at 1 μmol/L significantly decreased VDD, RPF, Vmax and APA as compared with the cells treated with hypoxia only. Perfusion with pH 6.8 solution for 10 min, VDD, RPF, Vmax and APA significantly decreased, MDP notably increased, and APD50 and APD80 markedly shortened. Under the condition of acidosis for 10 min, lidocaine significantly decreased VDD, RPF and Vmax, and lengthened APD50 and APD80 as compared with the cells under the condition of acidosis alone. Perfusion with EPI at 10 μmol/L for 10 min resulted in significant increases in VDD, RPF, Vmax, MDP and APA, and notable shortenings of APD50 and APD80, were also observed. Compared with 10 μmol/L EPI group, 1 μmol/L lidocaine +10 μmol/L EPI significantly reduced VDD, RPF, MDP and APA, and lengthened APD50, and APD80. CONCLUSION

  11. Ventricular Assist Device Support

    Science.gov (United States)

    Fasseas, Panayotis; Kutalek, Steven P.; Samuels, Fania L.; Holmes, Elena C.; Samuels, Louis E.

    2002-01-01

    We describe herein the cases of 2 patients who had ventricular arrhythmias. In one, a short-term biventricular assist device, the ABIOMED BVS 5000, was placed because the patient had sustained ventricular tachycardia and could not be weaned from cardiopulmonary bypass. Excellent hemodynamic support was maintained for several days while the antiarrhythmic therapy was maximized. Sinus rhythm was restored, and the patient was successfully weaned from the ventricular assist device. However, the substrate for the arrhythmia persisted, and a recurrence, 1 week later, resulted in the patient's death. In the 2nd patient, the use of an implantable left ventricular assist device was successful in temporarily alleviating the ventricular tachycardia associated with ischemic cardiomyopathy. However, after 2 days of device assistance, the patient experienced a recurrence of the tachycardia, which degenerated into ventricular fibrillation with a marked deterioration in the patient's hemodynamics. The arrhythmia persisted despite multiple attempts at external cardioversion, and internal cardioversion and placement of an automatic implantable cardioverter-defibrillator were necessary. This treatment, along with repeated boluses of amiodarone, led to successful suppression of the arrhythmias, and the patient eventually underwent transplantation. The mechanical hemodynamic support of the circulation by ventricular assist devices was effective in supporting these 2 patients who had sustained ventricular arrhythmias. (Tex Heart Inst J 2002;29:33–6) PMID:11995847

  12. Ventricular tachycardia in acromegaly.

    Science.gov (United States)

    Arias, Miguel A; Pachón, Marta; Rodríguez-Padial, Luis

    2011-02-01

    Cases of sudden cardiac death have been reported in patients with acromegaly. Malignant ventricular arrhythmias may play an important role in this fatal complication, but the exact mechanisms are not well understood. We report on an acromegalic patient presenting with documented recurrent syncopal ventricular tachycardia.

  13. Pathophysiological mechanisms of insulin resistance

    NARCIS (Netherlands)

    Brands, M.

    2013-01-01

    In this thesis we studied pathophysiological mechanisms of insulin resistance in different conditions in humans, i.e. in obesity, during lipid infusions, after hypercaloric feeding, and glucocorticoid treatment. We focused on 3 important hypotheses that are suggested to be implicated in the pathophy

  14. Pathophysiological mechanisms of insulin resistance

    NARCIS (Netherlands)

    Brands, M.

    2013-01-01

    In this thesis we studied pathophysiological mechanisms of insulin resistance in different conditions in humans, i.e. in obesity, during lipid infusions, after hypercaloric feeding, and glucocorticoid treatment. We focused on 3 important hypotheses that are suggested to be implicated in the pathophy

  15. Pathophysiological mechanisms of insulin resistance

    NARCIS (Netherlands)

    Brands, M.

    2013-01-01

    In this thesis we studied pathophysiological mechanisms of insulin resistance in different conditions in humans, i.e. in obesity, during lipid infusions, after hypercaloric feeding, and glucocorticoid treatment. We focused on 3 important hypotheses that are suggested to be implicated in the

  16. On renal pathophysiology in preeclampsia

    NARCIS (Netherlands)

    Penning, Maria Elisabeth (Marlies)

    2014-01-01

    Preeclampsia is a complication of pregnancy which can suddenly change from a relatively mild phenotype into a life-threatening situation. One of the organs that is always involved during preeclampsia is the kidney. The placenta plays an important role in the renal pathophysiology of preeclampsia. Th

  17. [Pathophysiology and treatment of ARMD].

    Science.gov (United States)

    Musat, O; Ochinciuc, Uliana; Gutu, Tatiana; Cristescu, T R; Coman, Corina

    2012-01-01

    A review regarding the pathophysiology of AMD as shown in the literature Targets in AMD treatment include: 1. Protection against oxidative stress; 2. Prevention of the accumulation of lipofuscin; 3. Reduction or elimination of chronic inflammation; 4. Changes involving the participation of complement inflammatory phenomena; 5. Changes in the phenomena of chronic inflammation which do not involve the participation of complement (eg. Mitochondria and extracellular matrix). The Neovascularization process includes: 1. Production of angiogenic factor; 2. Release of angiogenic factor; 3. The binding of factors to extracellular receptors and activation of intracellular signaling; 4. Activation of endothelial cells with basement membrane degradation; 5. Endothelial cell proliferation; 6. Endothelial cell migration; 7. Remodeling of extracellular matrix; 8. Tube formation; 9. Vascular stabilization. Therapy inAMD, based on physiological characteristics of early and late stages, is possible nowadays. It is possible to apply a specific treatment for each stage of AMD, but effective treatment requires combinations of specific therapeutic remedies involving different pathophysiological pathways.

  18. Pathophysiology of cutaneous lupus erythematosus

    OpenAIRE

    Achtman, Jordan C; Werth, Victoria P.

    2015-01-01

    The pathophysiology of cutaneous lupus erythematosus (CLE) encompasses the complex interactions between genetics, the environment, and cells and their products. Recent data have provided enhanced understanding of these interactions and the mechanism by which they cause disease. A number of candidate genes have been identified which increase the risk of developing CLE. Ultraviolet radiation, the predominant environmental exposure associated with CLE, appears to initiate CLE lesion formation by...

  19. On renal pathophysiology in preeclampsia

    OpenAIRE

    2014-01-01

    Preeclampsia is a complication of pregnancy which can suddenly change from a relatively mild phenotype into a life-threatening situation. One of the organs that is always involved during preeclampsia is the kidney. The placenta plays an important role in the renal pathophysiology of preeclampsia. The placenta produces excessive amounts of anti-angiogenic factors which are associated with systemic endothelial dysfunction. Although the underlying mechanisms of renal injury during preeclampsia r...

  20. Sepsis Pathophysiology and Anesthetic Consideration

    OpenAIRE

    Yuki, Koichi; Murakami, Naoka

    2015-01-01

    Sepsis remains to be a significant health care issue associated with high mortality and healthcare cost, despite the extensive effort to better understand the pathophysiology of the sepsis. Recently updated clinical guideline for severe sepsis and septic shock, “Surviving Sepsis Campaign 2012”, emphasizes the importance of early goal-directed therapy, which can be implemented in intraoperative management of sepsis patients. Herein, we review the updates of current guideline and discuss its ap...

  1. Cardiac MRI and Transthoracic Echocardiography of Left Ventricular Myocardial Noncompaction in A Patient with Congestive Heart Failure: A Case Report

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Eui Min; Byun, Joo Nam [Chosun University Hospital College of Medicine, Gwangju (Korea, Republic of); Kim, Dong Hun [Soonchunhyang University Hospital Bucheon College of Medicine, Bucheon (Korea, Republic of)

    2010-11-15

    We report a case of a 38-year-old male presenting with new-onset dyspnea, that was diagnosed as left ventricular noncompaction by transthoracic echocardiographic and cardiac MR. The tests revealed left ventricular systolic dysfunction with prominent trabeculations associated with deep intertrabecular recesses and an enddiastolic noncompacted to compacted ratio of 2.5 in the whole apical wall and mid-ventricular anterolateral and inferolateral walls. Delayed gadolinium contrast-enhanced MRI revealed subepicardial mid-wall hyperenhancement of the midventricular anteroseptal and inferoseptal walls, which suggested myocardial fibrosis. We review the pathophysiology, clinical characteristics, and diagnostic approach of the left ventricular noncompaction associated with congestive heart failure

  2. Passive ventricular remodeling in cardiac disease: Focus on heterogeneity

    Directory of Open Access Journals (Sweden)

    Elise L Kessler

    2014-12-01

    Full Text Available Passive ventricular remodeling is defined by the process of molecular ventricular adaptation to different forms of cardiac pathophysiology. It includes changes in tissue architecture, such as hypertrophy, fiber disarray, alterations in cell size and fibrosis. Besides that, it also includes molecular remodeling of gap junctions, especially those composed by Connexin43 proteins (Cx43 in the ventricles that affect cell-to-cell propagation of the electrical impulse, and changes in the sodium channels that modify excitability. All those alterations appear mainly in a heterogeneous manner, creating irregular and inhomogeneous electrical and mechanical coupling throughout the heart. This can predispose to reentry arrhythmias and adds to a further deterioration into heart failure. In this review, passive ventricular remodeling is described in Hypertrophic Cardiomyopathy (HCM, Dilated Cardiomyopathy (DCM, Ischemic Cardiomyopathy (ICM, and Arrhythmogenic Cardiomyopathy (ACM, with a main focus on the heterogeneity of those alterations mentioned above.

  3. Right ventricular dysfunction affects survival after surgical left ventricular restoration.

    Science.gov (United States)

    Couperus, Lotte E; Delgado, Victoria; Palmen, Meindert; van Vessem, Marieke E; Braun, Jerry; Fiocco, Marta; Tops, Laurens F; Verwey, Harriëtte F; Klautz, Robert J M; Schalij, Martin J; Beeres, Saskia L M A

    2017-04-01

    Several clinical and left ventricular parameters have been associated with prognosis after surgical left ventricular restoration in patients with ischemic heart failure. The aim of this study was to determine the prognostic value of right ventricular function. A total of 139 patients with ischemic heart failure (62 ± 10 years; 79% were male; left ventricular ejection fraction 27% ± 7%) underwent surgical left ventricular restoration. Biventricular function was assessed with echocardiography before surgery. The independent association between all-cause mortality and right ventricular fractional area change, tricuspid annular plane systolic excursion, and right ventricular longitudinal peak systolic strain was assessed. The additive effect of multiple impaired right ventricular parameters on mortality also was assessed. Baseline right ventricular fractional area change was 42% ± 9%, tricuspid annular plane systolic excursion was 18 ± 3 mm, and right ventricular longitudinal peak systolic strain was -24% ± 7%. Within 30 days after surgery, 15 patients died. Right ventricular fractional area change (hazard ratio, 0.93; 95% confidence interval, 0.88-0.98; P right ventricular longitudinal peak systolic strain (hazard ratio, 1.15; 95% confidence interval, 1.05-1.26; P Right ventricular function was impaired in 21%, 20%, and 27% of patients on the basis of right ventricular fractional area change, tricuspid annular plane systolic excursion, and right ventricular longitudinal peak systolic strain, respectively. Any echocardiographic parameter of right ventricular dysfunction was present in 39% of patients. The coexistence of several impaired right ventricular parameters per patient was independently associated with increased 30-day mortality (hazard ratio, 2.83; 95% confidence interval, 1.64-4.87, P right ventricular systolic dysfunction is independently associated with increased mortality in patients with ischemic heart failure undergoing surgical left

  4. Left Ventricular Hypertrophy

    Science.gov (United States)

    ... the chamber itself also increases. The enlarged heart muscle loses elasticity and eventually may fail to pump with as much force as needed. Left ventricular hypertrophy is more common in people who have uncontrolled ...

  5. Effects of Electrical Stimulation During Absolute Refractory Period on Contraction and Relaxation of Cardiomyocytes from Normal Guinea-pigs

    Institute of Scientific and Technical Information of China (English)

    赵晓静; 崔长琮; 张海柱

    2003-01-01

    Objectives To investi- gate the effect of electrical stimulation during absoluterefractory period on contraction and relaxation of ven-tricular myocytes from normal guinea-pigs. MethodsThe guinea -pig ventricular myocytes were obtainedby enzyme digesting, and the extent of its contractionand relaxation and Ca2+ transient were recordedthrough the motion edge detection system. Resultsmyocytes increased 15.45±6.48%, and the peakvelocity of shorting (contraction) and the peak velocity of relengthening (relaxation) increased 15.97±8.37% and 21.63 ± 8.06% respectively ( n = 10 );tio(360/380) (F360/F380) increased 22. 55 ± 9.08%,and the peak velocity of ventricular myocytes F360/F380 increased 36.75 ± 9.77% and 23.62 ± 4.47%during shorting and relengthening respectively (n =6) . Conclusions Appropriate electrical stimulationmay strengthen the contracting and relaxing function ofnormal guinea- pig ventricular myocytes.

  6. ANALYSIS OF RANDOMNESS OF ATRIAL AND VENTRICULAR RHYTHM IN ATRIAL-FIBRILLATION

    NARCIS (Netherlands)

    VANDENBERG, MP; DELANGEN, CDJ; HAAKSMA, J; BEL, KJ; CRIJNS, HJGM; DIJK, WA; LIE, KI

    1995-01-01

    The aim of the present study was top examine the relationship between randomness of atrial and ventricular rhythm during atrial fibrillation. Atrial fibrillation was induced in 10 open-chest pigs by application of metacholine on the surface of the right atrium followed by incremental pacing. Local a

  7. Molecular pathophysiology of cerebral edema.

    Science.gov (United States)

    Stokum, Jesse A; Gerzanich, Volodymyr; Simard, J Marc

    2016-03-01

    Advancements in molecular biology have led to a greater understanding of the individual proteins responsible for generating cerebral edema. In large part, the study of cerebral edema is the study of maladaptive ion transport. Following acute CNS injury, cells of the neurovascular unit, particularly brain endothelial cells and astrocytes, undergo a program of pre- and post-transcriptional changes in the activity of ion channels and transporters. These changes can result in maladaptive ion transport and the generation of abnormal osmotic forces that, ultimately, manifest as cerebral edema. This review discusses past models and current knowledge regarding the molecular and cellular pathophysiology of cerebral edema.

  8. Molecular pathophysiology of cerebral edema

    Science.gov (United States)

    Gerzanich, Volodymyr; Simard, J Marc

    2015-01-01

    Advancements in molecular biology have led to a greater understanding of the individual proteins responsible for generating cerebral edema. In large part, the study of cerebral edema is the study of maladaptive ion transport. Following acute CNS injury, cells of the neurovascular unit, particularly brain endothelial cells and astrocytes, undergo a program of pre- and post-transcriptional changes in the activity of ion channels and transporters. These changes can result in maladaptive ion transport and the generation of abnormal osmotic forces that, ultimately, manifest as cerebral edema. This review discusses past models and current knowledge regarding the molecular and cellular pathophysiology of cerebral edema. PMID:26661240

  9. Narcolepsy: Pathophysiology and Neuropsychological Changes

    Directory of Open Access Journals (Sweden)

    Angela Naumann

    2003-01-01

    Full Text Available Narcolepsy is now recognized as a distinctive disorder with specific pathophysiology and neurochemical abnormalities. Findings on the role of the neuropeptide hypocretin are opening new avenues of research and new strategies for therapy. Recently, neuropsychological and electrophysiological studies have provided evidence for reduced memory performance on standard memory tests in addition to subjective complaints of forgetfulness which may be related to changes in attentional processing. Further studies are, however, necessary to clarify the neuropsychological profile in narcolepsy. This review focuses on the recent advances in understanding narcolepsy.

  10. Pathophysiology of hemolytic transfusion reactions.

    Science.gov (United States)

    Davenport, Robertson D

    2005-07-01

    Hemolytic transfusion reactions (HTR) are systemic reactions provoked by immunologic red blood cell (RBC) incompatibility. Clinical and experimental observations of such reactions indicate that they proceed through phases of humoral immune reaction, activation of phagocytes, productions of cytokine mediators, and wide-ranging cellular responses. HTR have many features in common with the systemic inflammatory response syndrome (SIRS). Knowledge of the pathophysiologic mechanisms in HTR suggest that newer biological agents that target complement intermediates or proinflammatory cytokines may be effective agents in the treatment of severe HTRs.

  11. Group 2 Pulmonary Hypertension: Pulmonary Venous Hypertension: Epidemiology and Pathophysiology.

    Science.gov (United States)

    Clark, Craig B; Horn, Evelyn M

    2016-08-01

    Pulmonary hypertension from left heart disease (PH-LHD) is the most common form of PH, defined as mean pulmonary artery pressure ≥25 mm Hg and pulmonary artery wedge pressure ≥15 mm Hg. PH-LHD development is associated with more severe left-sided disease and its presence portends a poor prognosis, particularly once right ventricular failure develops. Treatment remains focused on the underlying LHD and despite initial enthusiasm for PH-specific therapies, most studies have been disappointing and their routine clinical use cannot be recommended. More work is urgently needed to better understand the pathophysiology underlying this disease and to develop effective therapeutic strategies. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Pathophysiology of the Belgrade Rat

    Directory of Open Access Journals (Sweden)

    Tania eVeuthey

    2014-04-01

    Full Text Available The Belgrade rat is an animal model of Divalent Metal Transporter-1 (DMT1 deficiency. This strain originates from an X-irradiation experiment first reported in 1966. Since then, the Belgrade rat’s pathophysiology has helped to reveal the importance of iron balance and the role of DMT1. This review discusses our current understanding of iron transport homeostasis and summarizes molecular details of DMT1 function. We describe how studies of the Belgrade rat have revealed key roles for DMT1 in iron distribution to red blood cells as well as duodenal iron absorption. The Belgrade rat’s pathology has extended our knowledge of hepatic iron handling, pulmonary and olfactory iron transport as well as brain iron uptake and renal iron handling. For example, relationships between iron and manganese metabolism have been discerned since both are essential metals transported by DMT1. Pathophysiologic features of the Belgrade rat provide us with a unique and interesting animal model to understand iron homeostasis.

  13. Pathophysiology of Equine Neonatal Septicemia

    Directory of Open Access Journals (Sweden)

    Juan Carlos Ospina Chirivi

    2014-07-01

    Full Text Available Neonatal septicemia is a major cause of mortality and morbidity in horses in their first seven days of life and within their pathophysiology. It is important to consider the extrinsic and intrinsic predisposing factors which make foals susceptible to agents of primarily bacterial etiology. However, other types of infectious etiology (viruses and fungi should be considered too, as well as noninfectious etiologies. The paper mentions a wide variety of mechanisms that produce different injuries that must be addressed with measures of critical neonatal care, so it is imperative for the veterinarian to know the pathogenic mechanisms of the disease, its clinical presentation and anatomo-pathological lesions. Thus, systemic inflammatory response syndrome (SIRS, multiple organ dysfunction syndrome (MODS, and peripheral circulatory collapse or shock are some of the elements defined as the pillars of the pathophysiology of neonatal septicemia, extensively studied in equine medicine. This paper presents a short review of the triggering mechanisms of neonatal septicemia highlighting the importance of epidemiological investigations in Colombia. It shows the need for retrospective and prospective studies and for divulgation of some of the preventive measures of the disease in horses.

  14. Vulnerability to ventricular fibrillation

    Science.gov (United States)

    Janse, Michiel J.

    1998-03-01

    One of the factors that favors the development of ventricular fibrillation is an increase in the dispersion of refractoriness. Experiments will be described in which an increase in dispersion in the recovery of excitability was determined during brief episodes of enhanced sympathetic nerve activity, known to increase the risk of fibrillation. Whereas in the normal heart ventricular fibrillation can be induced by a strong electrical shock, a premature stimulus of moderate intensity only induces fibrillation in the presence of regional ischemia, which greatly increases the dispersion of refractoriness. One factor that is of importance for the transition of reentrant ventricular tachycardia to ventricular fibrillation during acute regional ischemia is the subendocardial Purkinje system. After selective destruction of the Purkinje network by lugol, reentrant tachycardias still develop in the ischemic region, but they do not degenerate into fibrillation. Finally, attempts were made to determine the minimal mass of thin ventricular myocardium required to sustain fibrillation induced by burst pacing. This was done by freezing of subendocardial and midmural layers. The rim of surviving epicardial muscle had to be larger than 20 g. Extracellular electrograms during fibrillation in both the intact and the "frozen" left ventricle were indistinguishable, but activation patterns were markedly different. In the intact ventricle epicardial activation was compatible with multiple wavelet reentry, in the "frozen" heart a single, or at most two wandering reentrant waves were seen.

  15. Left ventricular dyssynchrony in patients with heart failure and preserved ejection fraction

    NARCIS (Netherlands)

    Santos, Angela B. S.; Kraigher-Krainer, Elisabeth; Bello, Natalie; Claggett, Brian; Zile, Michael R.; Pieske, Burkert; Voors, Adriaan A.; McMurray, John J. V.; Packer, Milton; Bransford, Toni; Lefkowitz, Marty; Shah, Amil M.; Solomon, Scott D.

    2014-01-01

    Aims Mechanical dyssynchrony has been postulated to play a pathophysiologic role in heart failure with preserved ejection fraction (HFpEF). Methods and results We quantified left ventricular (LV) systolic dyssynchrony in 130 HFpEF patients with NYHA class II-IV symptoms, ejection fraction (EF) 45, a

  16. Smallholder pig production

    DEFF Research Database (Denmark)

    Braae, Uffe Christian; Ngowi, Helena; Johansen, Maria Vang

    2013-01-01

    -ranging of pigs and presence of neighbouring pigs were also identified as risk factors for the presence of lice. Three species of fleas were identified; Tunga penetrans, Echidnophaga gallinacea and Ctenocephalides canis. The prevalence of fleas was 5% and 13% within confined and free-range, respectively. Two pigs...

  17. Genetically engineered SCN5A mutant pig hearts exhibit conduction defects and arrhythmias.

    Science.gov (United States)

    Park, David S; Cerrone, Marina; Morley, Gregory; Vasquez, Carolina; Fowler, Steven; Liu, Nian; Bernstein, Scott A; Liu, Fang-Yu; Zhang, Jie; Rogers, Christopher S; Priori, Silvia G; Chinitz, Larry A; Fishman, Glenn I

    2015-01-01

    SCN5A encodes the α subunit of the major cardiac sodium channel Na(V)1.5. Mutations in SCN5A are associated with conduction disease and ventricular fibrillation (VF); however, the mechanisms that link loss of sodium channel function to arrhythmic instability remain unresolved. Here, we generated a large-animal model of a human cardiac sodium channelopathy in pigs, which have cardiac structure and function similar to humans, to better define the arrhythmic substrate. We introduced a nonsense mutation originally identified in a child with Brugada syndrome into the orthologous position (E558X) in the pig SCN5A gene. SCN5A(E558X/+) pigs exhibited conduction abnormalities in the absence of cardiac structural defects. Sudden cardiac death was not observed in young pigs; however, Langendorff-perfused SCN5A(E558X/+) hearts had an increased propensity for pacing-induced or spontaneous VF initiated by short-coupled ventricular premature beats. Optical mapping during VF showed that activity often began as an organized focal source or broad wavefront on the right ventricular (RV) free wall. Together, the results from this study demonstrate that the SCN5A(E558X/+) pig model accurately phenocopies many aspects of human cardiac sodium channelopathy, including conduction slowing and increased susceptibility to ventricular arrhythmias.

  18. Left ventricular apical diseases.

    Science.gov (United States)

    Cisneros, Silvia; Duarte, Ricardo; Fernandez-Perez, Gabriel C; Castellon, Daniel; Calatayud, Julia; Lecumberri, Iñigo; Larrazabal, Eneritz; Ruiz, Berta Irene

    2011-08-01

    There are many disorders that may involve the left ventricular (LV) apex; however, they are sometimes difficult to differentiate. In this setting cardiac imaging methods can provide the clue to obtaining the diagnosis. The purpose of this review is to illustrate the spectrum of diseases that most frequently affect the apex of the LV including Tako-Tsubo cardiomyopathy, LV aneurysms and pseudoaneurysms, apical diverticula, apical ventricular remodelling, apical hypertrophic cardiomyopathy, LV non-compaction, arrhythmogenic right ventricular dysplasia with LV involvement and LV false tendons, with an emphasis on the diagnostic criteria and imaging features. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s13244-011-0091-6) contains supplementary material, which is available to authorized users.

  19. Fisiopatologia da enxaqueca Migraine pathophysiology

    Directory of Open Access Journals (Sweden)

    MAURICE B. VINCENT

    1998-12-01

    Full Text Available A fisiopatologia da enxaqueca ainda não foi completamente elucidada. As principais estruturas envolvidas parecem ser o sistema nervoso central (córtex e tronco cerebral, o sistema trigeminovascular e os vasos correspondentes, outras fibras autonômicas que inervam estes vasos, e os vários agentes vasoativos locais, como a SP, CGRP, NO, VIP, NPY, ACh, NA, NKA, entre outros. A depressão alastrante é o fenômeno neurológico que provavelmente justifica achados experimenais e clínicos na enxaqueca. Ela tem velocidade de propagação semelhante à aura, ativa o núcleo espinhal do trigêmeo e está relacionada à liberação de CGRP e NO. Alterações circulatórias detectadas por métodos complementares reforçam o papel da depressão alastrante. A identificação de anormalidades em pelo menos três loci (cromossomas 19 e 1 na enxaqueca hemiplégica familiar ocorreu recentemente. Elas estão relacionadas a anormalidades nos canais de cálcio voltagem dependentes tipo P/Q, específicos do sistema nervoso central, que regulam a liberação de vários neurotransmissores, incluindo possivelmente a serotonina. A exemplo de outras anormalidades neurológicas paroxísticas que resultam da hiperexcitabilidade da membrana plasmática, é possível que a enxaqueca ocorra devido a uma desordem de canais iônicos.The pathophysiology of migraine is not yet fully understood. The most important structures involved seem to be the central nervous system (cortex and brain stem, the trigeminovascular system and related cranial arteries, other autonomic fibres innervating such vessels, and various local vasoactive agents, including SP, CGRP, NO, VIP, NPY, ACh, NA, NKA, among others. The spreading depression phenomenon may explain clinical as well experimental findings in migraine. Its propagation velocity mirrors what is found in clinical aura, it may activate the spinal trigeminal nucleus and may induce CGRP and NO release. Circulatory changes detected with

  20. Transgenesis for pig models

    Science.gov (United States)

    Yum, Soo-Young; Yoon, Ki-Young; Lee, Choong-Il; Lee, Byeong-Chun

    2016-01-01

    Animal models, particularly pigs, have come to play an important role in translational biomedical research. There have been many pig models with genetically modifications via somatic cell nuclear transfer (SCNT). However, because most transgenic pigs have been produced by random integration to date, the necessity for more exact gene-mutated models using recombinase based conditional gene expression like mice has been raised. Currently, advanced genome-editing technologies enable us to generate specific gene-deleted and -inserted pig models. In the future, the development of pig models with gene editing technologies could be a valuable resource for biomedical research. PMID:27030199

  1. Understanding changes in cardiovascular pathophysiology.

    Science.gov (United States)

    Chummun, Harry

    Cardiovascular pathophysiological changes, such as hypertension and enlarged ventricles, reflect the altered functions of the heart and its circulation during ill-health. This article examines the normal and altered anatomy of the cardiac valves, the contractile elements and enzymes of the myocardium, the significance of the different factors associated with cardiac output, and the role of the autonomic nervous system in the heart beat. It also explores how certain diseases alter these functions and result in cardiac symptoms. Nurses can benefit from knowledge of these specific changes, for example, by being able to ask relevant questions in order to ascertain the nature of a patients condition, by being able to take an effective patient history and by being able to read diagnostic results, such as electrocardiograms and cardiac enzyme results. All this will help nurses to promote sound cardiac care based on a physiological rationale.

  2. Pathophysiological Study of Sensitive Skin.

    Science.gov (United States)

    Buhé, Virginie; Vié, Katell; Guéré, Christelle; Natalizio, Audrey; Lhéritier, Céline; Le Gall-Ianotto, Christelle; Huet, Flavien; Talagas, Matthieu; Lebonvallet, Nicolas; Marcorelles, Pascale; Carré, Jean-Luc; Misery, Laurent

    2016-03-01

    Sensitive skin is a clinical syndrome characterized by the occurrence of unpleasant sensations, such as pruritus, burning or pain, in response to various factors, including skincare products, water, cold, heat, or other physical and/or chemical factors. Although these symptoms suggest inflammation and the activation of peripheral innervation, the pathophysiogeny of sensitive skin remains unknown. We systematically analysed cutaneous biopsies from 50 healthy women with non-sensitive or sensitive skin and demonstrated that the intraepidermal nerve fibre density, especially that of peptidergic C-fibres, was lower in the sensitive skin group. These fibres are involved in pain, itching and temperature perception, and their degeneration may promote allodynia and similar symptoms. These results suggest that the pathophysiology of skin sensitivity resembles that of neuropathic pruritus within the context of small fibre neuropathy, and that environmental factors may alter skin innervation.

  3. [Pruritus: considerable progress in pathophysiology].

    Science.gov (United States)

    Misery, Laurent

    2014-12-01

    Pruritus is defined as "an unpleasant sensation that causes the need to scratch". This is not a small pain. It seems that pruriceptors exist but their level of separation from nociceptive receptors is still debated. Pathways of pruritus were identified from the skin (around the dermo-epidermal junction) to the brain. Many mediators are involved in pruritus but there are at least a histaminergic and a non-histaminergic pathway (PAR-2dependent). Similarly to pain, gate control or peripheral and central sensitization mechanisms have been highlighted in pruritus. These pathophysiological advances are important and anticipate therapeutic advances, that will be very useful for the symptomatic treatment of pruritus (poorly efficient at present).

  4. Dystonia : emerging concepts in pathophysiology.

    Directory of Open Access Journals (Sweden)

    Madhusudanan M

    1999-10-01

    Full Text Available The essential pathophysiological feature of dystonia is co-contraction of antagonistic muscles. This may be due to derangement of the spinal cord or cortical mechanism. In the cord, there is disruption of the normal reciprocal inhibition of antagonists during agonist contraction. This decreased reciprocal inhibition is due to reduced presynaptic inhibition of muscle afferent input to the inhibitory interneuron. The reduced presynaptic inhibition may in turn be either due to defective suprasegmental control or to changes in the tonic afferent input to the interneuron from cutaneous and muscle afferents. Alternatively, genesis of dystonia may entirely be a cortical mechanism. Overactivity of the premotor cortices, which receive projections from basal ganglia via ventral thalamus, could result in dystonia by abnormal activation of cortical motor neurons. This may again be due to a dopaminergic dysfunction of basal ganglia.

  5. Pathophysiologic mechanisms of biomedical nanomaterials.

    Science.gov (United States)

    Wang, Liming; Chen, Chunying

    2016-05-15

    Nanomaterials (NMs) have been widespread used in biomedical fields, daily consuming, and even food industry. It is crucial to understand the safety and biomedical efficacy of NMs. In this review, we summarized the recent progress about the physiological and pathological effects of NMs from several levels: protein-nano interface, NM-subcellular structures, and cell-cell interaction. We focused on the detailed information of nano-bio interaction, especially about protein adsorption, intracellular trafficking, biological barriers, and signaling pathways as well as the associated mechanism mediated by nanomaterials. We also introduced related analytical methods that are meaningful and helpful for biomedical effect studies in the future. We believe that knowledge about pathophysiologic effects of NMs is not only significant for rational design of medical NMs but also helps predict their safety and further improve their applications in the future.

  6. Allogeneic guinea pig mesenchymal stem cells ameliorate neurological changes in experimental colitis

    OpenAIRE

    Stavely, Rhian; Robinson, Ainsley M.; Miller, Sarah; Boyd, Richard; Sakkal, Samy; Nurgali, Kulmira

    2015-01-01

    Background The use of mesenchymal stem cells (MSCs) to treat inflammatory bowel disease (IBD) is of great interest because of their immunomodulatory properties. Damage to the enteric nervous system (ENS) is implicated in IBD pathophysiology and disease progression. The most commonly used model to study inflammation-induced changes to the ENS is 2,4,6-trinitrobenzene-sulfonate acid (TNBS)-induced colitis in guinea pigs; however, no studies using guinea pig MSCs in colitis have been performed. ...

  7. Emergency mitral valve replacement for acute severe mitral regurgitation following balloon mitral valvotomy: Pathophysiology of hemodynamic collapse and peri-operative management issues

    Directory of Open Access Journals (Sweden)

    Praveen Reddy Bayya

    2014-01-01

    Full Text Available Severe mitral regurgitation (MR following balloon mitral valvotomy (BMV needing emergent mitral valve replacement is a rare complication. The unrelieved mitral stenosis is compounded by severe MR leading to acute rise in pulmonary hypertension and right ventricular afterload, decreased coronary perfusion, ischemia and right ventricular failure. Associated septal shift and falling left ventricular preload leads to a vicious cycle of myocardial ischemia and hemodynamic collapse and needs to be addressed emergently before the onset of end organ damage. In this report, we describe the pathophysiology of hemodynamic collapse and peri-operative management issues in a case of mitral valve replacement for acute severe MR following BMV.

  8. Left ventricular wall stress compendium.

    Science.gov (United States)

    Zhong, L; Ghista, D N; Tan, R S

    2012-01-01

    Left ventricular (LV) wall stress has intrigued scientists and cardiologists since the time of Lame and Laplace in 1800s. The left ventricle is an intriguing organ structure, whose intrinsic design enables it to fill and contract. The development of wall stress is intriguing to cardiologists and biomedical engineers. The role of left ventricle wall stress in cardiac perfusion and pumping as well as in cardiac pathophysiology is a relatively unexplored phenomenon. But even for us to assess this role, we first need accurate determination of in vivo wall stress. However, at this point, 150 years after Lame estimated left ventricle wall stress using the elasticity theory, we are still in the exploratory stage of (i) developing left ventricle models that properly represent left ventricle anatomy and physiology and (ii) obtaining data on left ventricle dynamics. In this paper, we are responding to the need for a comprehensive survey of left ventricle wall stress models, their mechanics, stress computation and results. We have provided herein a compendium of major type of wall stress models: thin-wall models based on the Laplace law, thick-wall shell models, elasticity theory model, thick-wall large deformation models and finite element models. We have compared the mean stress values of these models as well as the variation of stress across the wall. All of the thin-wall and thick-wall shell models are based on idealised ellipsoidal and spherical geometries. However, the elasticity model's shape can vary through the cycle, to simulate the more ellipsoidal shape of the left ventricle in the systolic phase. The finite element models have more representative geometries, but are generally based on animal data, which limits their medical relevance. This paper can enable readers to obtain a comprehensive perspective of left ventricle wall stress models, of how to employ them to determine wall stresses, and be cognizant of the assumptions involved in the use of specific models.

  9. Bone Mineral Density is an Independent Determinant of Left Ventricular Mass Index in the General Female Population

    OpenAIRE

    Lim, Young-Hyo; Shin, Jinho; Lee, Jae Ung; Lim, Heon Kil; Hong, Sangmo; Kim, Mi-Kyung; Choi, Bo Youl; Kim, Yu-Mi

    2010-01-01

    Background and Objectives Left ventricular hypertrophy (LVH) is a well known cardiovascular prognostic predictor. Osteoporosis has been suggested to be associated with cardiovascular disease. According to studies of primary hyperparathyroidism, a pathophysiological association between calcium metabolism and LVH has been suggested but is not yet fully understood. This study was performed to investigate the association between bone mineral density (BMD) and left ventricular mass index (LVMI) in...

  10. Obesity cardiomyopathy: pathogenesis and pathophysiology.

    Science.gov (United States)

    Wong, Chiew; Marwick, Thomas H

    2007-08-01

    Obesity is becoming a worldwide phenomenon. Myocardial changes associated with the obese state are increasingly recognized, independent of hypertension, obstructive sleep apnea and coronary artery disease. The existence of a cardiomyopathy of obesity is supported by a range of evidence: epidemiologic study findings, which have shown an association between obesity and heart failure; clinical studies that have confirmed the association of adiposity with left ventricular dysfunction, independent of hypertension, coronary artery disease and other heart disease; and experimental evidence of structural and functional changes in the myocardium in response to increased adiposity. The most important mechanisms in the development of obesity cardiomyopathy are metabolic disturbances (insulin resistance, increased free fatty acid levels, and also increased levels of adipokines), activation of the renin-angiotensin-aldosterone and sympathetic nervous systems, myocardial remodeling, and small-vessel disease (both microangiopathy and endothelial dysfunction). In the first part of this two-part Review, we seek to evaluate the emerging evidence for the existence of a cardiomyopathy of obesity and clarify the responsible mechanisms.

  11. Wound pruritus: pathophysiology and management

    Directory of Open Access Journals (Sweden)

    Paul JC

    2015-08-01

    Full Text Available Julia C PaulSchool of Nursing, Oakland University, Rochester, MI, USAPurpose: The objective of this article is to review literature on wound pruritus, with a focus on summarizing pathophysiology and management.Method: Literature related to the physiology of itch was reviewed. PubMed, MEDLINE, the Cumulative Index to Nursing and Allied Health Literature (CINAHL, and Embase were searched for all research studies written in English which include “wound” (injury/burn and “pruritus” (itch in the title or abstract. Articles were accepted if they involved wounds or acute burns. Literature related to options for management of wound pruritus was reviewed.Results: While all types of wounds can be the source of associated pruritus, most studies have been done concerning pruritus associated with burns. There are treatment options for pruritus which can be considered for management of wound pruritus. Conclusion: Further research is indicated to gain insights into the problem of wound pruritus. As more is learned about the physiology of wound pruritus, more effective management strategies can be developed and employed.Keywords: wound, chronic itch, C-fibers, spinothalamic tract, positron emission tomography, pruritogens

  12. Obesity: pathophysiology and clinical management.

    Science.gov (United States)

    Gurevich-Panigrahi, Tatiana; Panigrahi, Soumya; Wiechec, Emilia; Los, Marek

    2009-01-01

    Obesity is an increasingly serious socioeconomic and clinical problem. Between (1/4)-(1/3) of population in the developed countries can be classified as obese. Four major etiological factors for development of obesity are genetic determinants, environmental factors, food intake and exercise. Obesity increases the risk of the development of various pathologic conditions including: insulin-resistant diabetes mellitus, cardiovascular disease, non-alcoholic fatty liver disease, endocrine problems, and certain forms of cancer. Thus, obesity is a negative determinant for longevity. In this review we provide broad overview of pathophysiology of obesity. We also discuss various available, and experimental therapeutic methods. We highlight functions of adipocytes including fat storing capacity and secretory activity resulting in numerous endocrine effects like leptin, IL-6, adiponectin, and resistin. The anti-obesity drugs are classified according to their primary action on energy balance. Major classes of these drugs are: appetite suppressants, inhibitors of fat absorption (i.e. orlistat), stimulators of thermogenesis and stimulators of fat mobilization. The appetite suppressants are further divided into noradrenergic agents, (i.e. phentermine, phendimetrazine, benzphetamine, diethylpropion), serotoninergic agents (i.e. dexfenfluramine), and mixed noradrenergic-serotoninergic agents (i.e. sibutramine). Thus, we highlight recent advances in the understanding of the central neural control of energy balance, current treatment strategies for obesity and the most promising targets for the development of novel anti-obesity drugs.

  13. 急性激活α1和β1肾上腺素能受体对豚鼠心室肌细胞快激活延迟整流钾电流的交叉影响%Cross effects of acute adrenergic stimulation on rapid component of delayed rectifier potassium channel current in guinea-pig left ventricular myocytes

    Institute of Scientific and Technical Information of China (English)

    吴婷婷; 王森; 邹建刚; 曹克将; 许迪

    2014-01-01

    different subtype and both of adrenergic receptors (α1-AR or β1-AR) on the rapidly activating delayed rectifier potassium current ( IKr ) in guinea-pig ventricular myocytes,and the effects of acute stimulation of both α1-AR and β1-AR on IKr current. Methods Single ventricular myocyte was obtained from guinea-pig using enzymatic dissociation technique. Whole-cell patch clamp technique was used to record IKr current. The amplitudes of IKr current before and after stimulation of adrenergic receptors were measured to reflect the effects of acute stimulation of different adrener-gic receptors. The expression level of IKr channel protein after acute stimulation of different subtype of adrenergic receptors was detected by western-blot. Results Phenylephrine( PE) and xamoterol( Xamo) inhibited IKr cur-rent amplitude by a content dependent way,the IC50 was 0. 93 μmol/L and 6. 40 μmol/L respectively. In our study,1 μmol/L PE (PE group) reduced IKr current to 0. 79±0. 02,and shifted the voltage-dependent activa-ting curve to the negative voltage,where U0.5 changed from (-2. 99±1. 44) mV to (-9. 10±1. 74) mV,and k changed a little. 10μmol/L Xamo (Xamo group) reduced IKr current to 0. 72±0. 01,and shifted the voltage-de-pendent activating curve to the negative voltage, where U0. 5 changed from (-4. 54 ± 1. 48 ) mV to (-7. 24 ± 1. 93) mV,and k changed a little. While simultaneously administration of 1 μmol/L PE and 10 μmol/L Xamo (PE+Xamo group) only reduced IKr current to 0. 69±0. 02,and it also shifted the voltage-dependent activating curve to the negative voltage,where U0.5 changed from (-2. 71±1. 95) mV to (-8. 45±1. 97) mV,and k changed a little. In PE group, Xamo group and PE+XAMO group, IKr tail current amplitude decreased by (20. 73±2. 46)%,(27. 99±0. 68)% and (30. 56±1. 80)%,separately. By western-blot,the expression level of IKr channel protein after acute adrenergic stimulation did not show a statistical change. Conclusions Acute stimulation of α1-AR or

  14. A quantitative measurement of spatial order in ventricular fibrillation

    CERN Document Server

    Bayly, P V; Wolf, P D; Greenside, H S; Smith, W M; Ideker, R E

    1993-01-01

    As an objective measurement of spatial order in ventricular fibrillation (VF), spatial correlation functions and their characteristic lengths were estimated from epicardial electrograms of pigs in VF. The correlation length of the VF in pigs was found to be approximately 4-10 mm, varying as fibrillation progressed. The degree of correlation decreased in the first 4 seconds after fibrillation then increased over the next minute. The correlation length is much smaller than the scale of the heart, suggesting that many independent regions of activity exist on the epicardium at any one time. On the other hand, the correlation length is 4 to 10 times the interelectrode spacing, indicating that some coherence is present. These results imply that the heart behaves during VF as a high-dimensional, but not random, system involving many spatial degrees of freedom, which may explain the lack of convergence of fractal dimension estimates reported in the literature. Changes in the correlation length also suggest that VF re...

  15. Pig model for diabetes

    DEFF Research Database (Denmark)

    2016-01-01

    The present invention relates to a transgenic pig comprising a mutated IAPP gene and displaying a phenotype associated with diabetes. The invention also relates to a transgenic blastocyst, embryo, fetus, donor cell and/or cell nucleusderived from said transgenic pig. The invention further relates...... to use of the transgenic pig as a model system for studying therapy, treatment and/or prevention of diabetes....

  16. Effects of undiluted and diluted amiodarone on defibrillation and haemodynamics in a ventricular fibrillation pig model%胺碘酮原液和稀释液对心室颤动转复作用及血流动力学的影响

    Institute of Scientific and Technical Information of China (English)

    武军元; 李春盛; 王胜奇

    2010-01-01

    Objective Amiodarone was diluted to release the side effect of hypotension in clinic, but this maybe unsuitable during cardiopulmonary resuscitation (CPR). This study was designed to observe the effects of undiluted amiodarone, diluted amiodarone, and CPR alone on ventricular fibrillation (VF) in a pig model. Methods VF was induced in 21 pigs. The animals were randomly (random mumber) divided into 3 groups after VF 3 min.① CPR group ( n= 7): standard CPR; ② undiluted amiodarone group ( n= 7): undiluted amiodarone (5 mg/kg)bolus within 3 s, then 20 mL saline flush into the peripheral vein, CPR was started after observed 30 s; ③ diluted amiodarone group ( n = 7): amiodarone was dissolved in 20 mL saline and bolus with 30 s. Defibrillation was attempted at VF 5 min. Results The restoration of spontaneous circulation (ROSC) of CPR and undiluted amiodarone groups were higher than diluted group (85.7% vs. 71.4% vs. 42.9%), but the differences were not significant (all P >0.05). The defibrillation energy and times of CPR group were higher than that of undiluted amiodarone (P= 0.009) and diluted group ( P = 0. 170). The mean arterial pressure of undiluted amiodarone were lower than diluted and CPR groups at ROSC 10 min (all P <0.05), but the differences of undiluted and diluted groups were not significant after ROSC 0.5 h. Conclusions In this study, undiluted amiodaronecan effectively reduced the defibrillation times and energy. Although diluted amiodaronecan release the side effect of hypotension which was transient, it didn't significantly improved cardiac electric activity and delayed to start CPR.%目的 通过猪心室颤动(VF)模型,观察胺碘酮原液、稀释液以及单纯标准CPR对心肺复苏效果的影响.方法 21头北京长白猪,应用程控刺激仪诱导VF,VF 3 min后,将动物随机(随机数字法)分为3组.①单纯CPR组:只进行单纯标准CPR;②胺碘酮原液组:予胺碘酮原液5 mg/kg快速(<3 s)静推,生理盐水20 m

  17. Longitudinal strain bull's eye plot patterns in patients with cardiomyopathy and concentric left ventricular hypertrophy.

    Science.gov (United States)

    Liu, Dan; Hu, Kai; Nordbeck, Peter; Ertl, Georg; Störk, Stefan; Weidemann, Frank

    2016-05-10

    Despite substantial advances in the imaging techniques and pathophysiological understanding over the last decades, identification of the underlying causes of left ventricular hypertrophy by means of echocardiographic examination remains a challenge in current clinical practice. The longitudinal strain bull's eye plot derived from 2D speckle tracking imaging offers an intuitive visual overview of the global and regional left ventricular myocardial function in a single diagram. The bull's eye mapping is clinically feasible and the plot patterns could provide clues to the etiology of cardiomyopathies. The present review summarizes the longitudinal strain, bull's eye plot features in patients with various cardiomyopathies and concentric left ventricular hypertrophy and the bull's eye plot features might serve as one of the cardiac workup steps on evaluating patients with left ventricular hypertrophy.

  18. Active myocyte shortening during the 'isovolumetric relaxation' phase of diastole is responsible for ventricular suction; 'systolic ventricular filling'.

    Science.gov (United States)

    Buckberg, Gerald D; Castellá, Manuel; Gharib, Morteza; Saleh, Saleh

    2006-04-01

    To study the 'isovolumetric relaxation' phase of rapid ventricular filling by analysis of the shortening of cardiac muscle in the endocardial and epicardial segments of the left ventricle in the dual helical model of the ventricular band, described by Torrent-Guasp. In 10 pigs (27-82 kg), temporal shortening by sonomicrometer crystals was recorded while recording ECG, and measuring intraventricular pressure and dP/dt with Millar pressure transducers. The following sequence was observed; shortening began in descending or endocardial segment, and 82+/-23 ms later it was initiated in the epicardial or ascending segment of the band. The descending segment stops shortening during the rapid filling phase of fast descent of ventricular pressure, but the ascending segment shortening continues for 92+/-33 ms, so that active shortening continues during the period of isovolumetric relaxation. During the rapid filling phase, dopamine decreased the interval between completion of endocardial and termination of epicardial contraction from 92+/-20 to 33+/-8 ms. Conversely propranolol delayed the start of epicardial shortening from 82+/-23 to 121+/-20 ms, and prolonged the duration of endocardial contraction, causing a closer (21+/-5 ms vs 92+/-20 ms) interval between termination of contraction of endocardial and epicardial fibers. The resultant slope of the rapid descent of the left ventricular pressure curve became prolonged. These time sequences show that ongoing unopposed ascending segment shortening occurs during the phase of rapid fall of ventricular pressure. These active shortening phases respond to positive and negative inotropic stimulation, and indicate the classic concept of 'isovolumetric relaxation', IVR, must be reconsidered, and the new term 'isovolumetric contraction', IVC, or systolic ventricular filing may be used.

  19. Ventricular Assist Device Support: for Management of Sustained Ventricular Arrhythmias

    OpenAIRE

    2002-01-01

    We describe herein the cases of 2 patients who had ventricular arrhythmias. In one, a short-term biventricular assist device, the ABIOMED BVS 5000, was placed because the patient had sustained ventricular tachycardia and could not be weaned from cardiopulmonary bypass. Excellent hemodynamic support was maintained for several days while the antiarrhythmic therapy was maximized. Sinus rhythm was restored, and the patient was successfully weaned from the ventricular assist device. However, the s...

  20. LATE POTENTIALS IN A PORCINE MODEL OF ANTERIOR WALL MYOCARDIAL-INFARCTION AND THEIR RELATION TO INDUCIBLE VENTRICULAR-TACHYCARDIA

    NARCIS (Netherlands)

    TOBE, TJM; DELANGEN, CDJ; MOOK, PH; TIO, RA; BEL, KJ; DEGRAEFF, PA; VANGILST, WH; WESSELING, H

    1992-01-01

    In this study, normal values for signal averaged electrocardiographic parameters were assessed in healthy pigs (n = 100) and the development of late potentials after myocardial infarction (n = 41) in relation to inducible ventricular tachycardia was investigated. Normal values are: filtered QRS dura

  1. Physiologic Basis and Pathophysiologic Implications of the Diastolic Properties of the Cardiac Muscle

    Directory of Open Access Journals (Sweden)

    João Ferreira-Martins

    2010-01-01

    Full Text Available Although systole was for long considered the core of cardiac function, hemodynamic performance is evenly dependent on appropriate systolic and diastolic functions. The recognition that isolated diastolic dysfunction is the major culprit for approximately fifty percent of all heart failure cases imposes a deeper understanding of its underlying mechanisms so that better diagnostic and therapeutic strategies can be designed. Risk factors leading to diastolic dysfunction affect myocardial relaxation and/or its material properties by disrupting the homeostasis of cardiomyocytes as well as their relation with surrounding matrix and vascular structures. As a consequence, slower ventricular relaxation and higher myocardial stiffness may result in higher ventricular filling pressures and in the risk of hemodynamic decompensation. Thus, determining the mechanisms of diastolic function and their implications in the pathophysiology of heart failure with normal ejection fraction has become a prominent field in basic and clinical research.

  2. Development of left ventricular hypertrophy in a novel porcine model of mitral regurgitation

    DEFF Research Database (Denmark)

    Ravn, Nathja; Zois, Nora Elisabeth; Moesgaard, Sophia Gry

    2014-01-01

    OBJECTIVES: We aimed to develop a porcine model for chronic nonischemic mitral regurgitation (MR) to investigate left ventricular (LV) enlargement and eccentric hypertrophy. DESIGN: Nonischemic MR was induced in 30 pigs by open-chest immobilization of the posterior mitral leaflet by transannular...... traction sutures that where applied in transmyocardial fashion. A sham operated control group (n = 13) was included. Echocardiographic LV size and heart weight assessed at euthanasia were used to evaluate the development of LV enlargement and eccentric hypertrophy after 8 weeks follow-up. RESULTS: Eight...... for chronic moderate to severe nonischemic MR with development of LV enlargement and eccentric hypertrophy within 8 weeks has been established in pigs....

  3. Effects of heat stress on carbohydrate and lipid metabolism in growing pigs

    Science.gov (United States)

    Heat stress (HS) jeopardizes human and animal health and reduces animal agriculture productivity; however, its pathophysiology is not well understood. Study objectives were to evaluate the effects of HS on basal and stimulated energetic metabolism. Crossbred female pigs (57±5 kg body weight) were ...

  4. Benchmarking ventricular arrhythmias in the mouse--revisiting the 'Lambeth Conventions' 20 years on.

    Science.gov (United States)

    Huggins, Catherine E; Bell, James R; Pepe, Salvatore; Delbridge, Lea M D

    2008-12-01

    The isolated Langendorff-mode perfused heart has become a valuable experimental model, used extensively to examine cardiac function, pathophysiology and pharmacology. For the clinical cardiologist an ECG is often a simple practicality, however in experimental circumstances, particularly with ex vivo murine hearts it is not always possible to obtain an ECG due to experimental recording constraints. However, the mechanical record of ventricular contractile function can be highly informative in relation to electrical state. It is difficult though to achieve consistency in these evaluations of arrhythmia as a validated common reference framework is lacking. In 1988, a group of investigators developed the 'Lambeth Conventions'--a standardised reference for the definition and classification of arrhythmias in animal experimental models of ischaemia, infarction and reperfusion in vivo. Now, two decades later it is timely to revisit the Lambeth Conventions, and to update the guidelines in the context of the marked increase in murine heart study in experimental cardiac pathophysiology. Here we describe an adjunct to the Lambeth Conventions for the reporting of ventricular arrhythmias post-ischaemia in ex vivo mouse hearts when ECG recordings are not employed. Of seven discrete and identifiable patterns of mechanical dysrhythmia observed in reperfusion, five could be classified using conventional ECG terminology: ventricular premature beat, bigeminy, trigeminy, ventricular tachycardia and ventricular fibrillation. Two additional rhythm variations detected from the pressure record are described (potentiated contraction and alternans).

  5. Ventricular assist device support for management of sustained ventricular arrhythmias.

    Science.gov (United States)

    Fasseas, Panayotis; Kutalek, Steven P; Samuels, Fania L; Holmes, Elena C; Samuels, Louis E

    2002-01-01

    We describe herein the cases of 2 patients who had ventricular arrhythmias. In one, a short-term biventricular assist device, the ABIOMED BVS 5000, was placed because the patient had sustained ventricular tachycardia and could not be weaned from cardiopulmonary bypass. Excellent hemodynamic support was maintained for several days while the antiarrhythmic therapy was maximized. Sinus rhythm was restored, and the patient was successfully weaned from the ventricular assist device. However, the substrate for the arrhythmia persisted, and a recurrence, 1 week later, resulted in the patient's death. In the 2nd patient, the use of an implantable left ventricular assist device was successful in temporarily alleviating the ventricular tachycardia associated with ischemic cardiomyopathy. However, after 2 days of device assistance, the patient experienced a recurrence of the tachycardia, which degenerated into ventricular fibrillation with a marked deterioration in the patient's hemodynamics. The arrhythmia persisted despite multiple attempts at external cardioversion, and internal cardioversion and placement of an automatic implantable cardioverter-defibrillator were necessary. This treatment, along with repeated boluses of amiodarone, led to successful suppression of the arrhythmias, and the patient eventually underwent transplantation. The mechanical hemodynamic support of the circulation by ventricular assist devices was effective in supporting these 2 patients who had sustained ventricular arrhythmias.

  6. Postpartal right ventricular thrombosis.

    Science.gov (United States)

    Velicki, Lazar; Milosavljević, Aleksandar; Majin, Marijan; Vujin, Bojan; Kovacević, Pavle

    2008-11-01

    The discovery of an intracardial mass in patients presents a serious diagnostic dilemma. The differential diagnosis of this condition may seem abundant, but myxomas and intracardial thrombosis are the most frequent diagnoses. A connection between pregnancy and the presence of thrombosis has been documented frequently. Normal pregnancy leads to changes of the coagulative and fibrinolytic status toward a hypercoagulable condition which has its own physiological justification (the risk of blood loss decreases during labor). The case of a patient suffering from postpartal right ventricular thrombosis, which was successfully resolved by surgery as described in this contribution, demonstrates the value of a multidisciplinary approach.

  7. Right ventricular metastasis of leiomyosarcoma

    Directory of Open Access Journals (Sweden)

    Stagmo Martin

    2009-05-01

    Full Text Available Abstract Metastatic presentation of leiomyosarcoma in the heart is very rare. We present transthoracic echocardiography and combined PET/CT images of a case with a large right ventricular metastasis of leiomyosarcoma. The patient was placed on cytostatic drugs for palliative purposes, but passed away one month later because of an untreatable ventricular tackycardia.

  8. Mitochondria and left ventricular hypertrophy

    Institute of Scientific and Technical Information of China (English)

    Haiyan Zhu; Shiwen Wang

    2008-01-01

    @@ Introduction Left ventricular hypertrophy (LVH) is one of the vicious organ damages of essential hypertension.It contributes a lot to high mortality of essential hypertension due to sudden cardiac death,ventricular arrhythmia and heart failure.Many factors involve in the pathogenesis of hypertension-induced LVH including inherited variants as well as environmental factors.

  9. Divertículo ventricular congênito associado à taquicardia ventricular Congenital ventricular diverticulum associated with ventricular tachycardia

    Directory of Open Access Journals (Sweden)

    Ranieli Pitol

    2005-02-01

    Full Text Available Divertículos ventriculares congênitos são raros. Clinicamente, podem ser assintomáticos ou causa de embolização sistêmica, insuficiência cardíaca, insuficiência valvar, ruptura ventricular, arritmia ventricular ou morte súbita. Apresentamos caso de uma mulher de 56 anos com taquicardia ventricular sustentada, na qual, durante a investigação, foi diagnosticada a presença de um divertículo na posição ínfero-basal do ventrículo esquerdo. Comentam-se as características clínicas e o tratamento desta doença infreqüente.Congenital ventricular diverticula are rare. Clinically, they may be asymptomatic or cause systemic embolization, heart failure, valvular regurgitation, ventricular rupture, ventricular arrhythmia, or sudden death. We report the case of a 56-year-old woman with sustained ventricular tachycardia, who, during investigation, was diagnosed with a diverticulum in the inferobasal portion of the left ventricle. The clinical characteristics and treatment of this rare disease are discussed.

  10. Diabetic cardiomyopathy:Pathophysiology,diagnostic evaluation and management

    Institute of Scientific and Technical Information of China (English)

    Joseph; M; Pappachan; George; I; Varughese; Rajagopalan; Sriraman; Ganesan; Arunagirinathan

    2013-01-01

    Diabetes affects every organ in the body and cardiovascular disease accounts for two-thirds of the mortality in the diabetic population.Diabetes-related heart disease occurs in the form of coronary artery disease(CAD),cardiac autonomic neuropathy or diabetic cardiomyopathy(DbCM).The prevalence of cardiac failure is high in the diabetic population and DbCM is a common but underestimated cause of heart failure in diabetes.The pathogenesis of diabetic cardiomyopathy is yet to be clearly defined.Hyperglycemia,dyslipidemia and inflammation are thought to play key roles in the generation of reactive oxygen or nitrogen species which are in turn implicated.The myocardial interstitium undergoes alterations resulting in abnormal contractile function noted in DbCM.In the early stages of the disease diastolic dysfunction is the only abnormality,but systolic dysfunction supervenes in the later stages with impaired left ventricular ejection fraction.Transmitral Doppler echocardiography is usually used to assess diastolic dysfunction,but tissue Doppler Imaging and Cardiac Magnetic Resonance Imaging are being increasingly used recently for early detection of DbCM.The management of DbCM involves improvement in lifestyle,control of glucose and lipid abnormalities,and treatment of hypertension and CAD,if present.The role of vasoactive drugs and antioxidants is being explored.This review discusses the pathophysiology,diagnostic evaluation and management options of DbCM.

  11. Right ventricular failure due to chronic pressure load: What have we learned in animal models since the NIH working group statement?

    OpenAIRE

    Marinus A. J. Borgdorff; Dickinson, Michael G.; Berger, Rolf M. F.; Bartelds, Beatrijs

    2015-01-01

    Right ventricular (RV) failure determines outcome in patients with pulmonary hypertension, congenital heart diseases and in left ventricular failure. In 2006, the Working Group on Cellular and Molecular Mechanisms of Right Heart Failure of the NIH advocated the development of preclinical models to study the pathophysiology and pathobiology of RV failure. In this review, we summarize the progress of research into the pathobiology of RV failure and potential therapeutic interventions. The pictu...

  12. Symbolic dynamics of ventricular tachycardia and ventricular fibrillation

    Science.gov (United States)

    Wang, Jun; Chen, Jie

    2010-05-01

    In this paper, the symbolic dynamics analysis was used to analyze the complexity of normal heartbeat signal (NSR), Ventricular tachycardia (VT) and ventricular fibrillation (VF) signals. By calculating the information entropy value of symbolic sequences, the complexities were quantified. Based on different information entropy values, NSR, VT and VF signals were distinguished with satisfactory results. The study showed that a sudden drop of symbolic sequence’s entropy value indicated that the patients most likely entered the episode of ventricular tachycardia and this was a crucial episode for the clinical treatment of patients. It had important clinical significance for the automatic diagnosis.

  13. Current concepts in the pathophysiology of glaucoma

    Directory of Open Access Journals (Sweden)

    Agarwal Renu

    2009-01-01

    Full Text Available Glaucoma, the second leading cause of blindness, is characterized by changes in the optic disc and visual field defects. The elevated intraocular pressure was considered the prime factor responsible for the glaucomatous optic neuropathy involving death of retinal ganglion cells and their axons. Extensive investigations into the pathophysiology of glaucoma now reveal the role of multiple factors in the development of retinal ganglion cell death. A better understanding of the pathophysiological mechanisms involved in the onset and progression of glaucomatous optic neuropathy is crucial in the development of better therapeutic options. This review is an effort to summarize the current concepts in the pathophysiology of glaucoma so that newer therapeutic targets can be recognized. The literature available in the National Medical Library and online Pubmed search engine was used for literature review.

  14. [Current insights into the pathophysiology of rosacea].

    Science.gov (United States)

    Schauber, J; Homey, B; Steinhoff, M

    2013-07-01

    Rosacea is a chronic inflammatory skin disease mainly affecting the face. Four major clinical subtypes of rosacea can be identified: erythemato-telangiectatic, papulopustular, phymatous and ocular rosacea. Still, it is currently unclear whether these subtypes develop consecutively or if any subtypes may occur individually as part of a syndrome. Rosacea is characterized by facial flushing, erythema, chronic inflammation, edema and fibrosis. Several trigger factors can worsen the disease or cause recurring episodes of inflammation. Although some aspects in the pathophysiology of rosacea have been characterized in more detail during the past years, the precise interplay of the various dysregulated systems is still poorly understood. In early disease manifestations and milder stages, dysfunction of neurovascular regulation and the innate immune system seem to be driving forces in rosacea pathophysiology. A disturbed chemokine and cytokine network further contributes to disease progression. This current review highlights some of the recent findings in rosacea pathophysiology and points out novel targets for therapeutic intervention.

  15. Imaging Alzheimer's disease pathophysiology with PET

    Directory of Open Access Journals (Sweden)

    Lucas Porcello Schilling

    Full Text Available ABSTRACT Alzheimer's disease (AD has been reconceptualised as a dynamic pathophysiological process characterized by preclinical, mild cognitive impairment (MCI, and dementia stages. Positron emission tomography (PET associated with various molecular imaging agents reveals numerous aspects of dementia pathophysiology, such as brain amyloidosis, tau accumulation, neuroreceptor changes, metabolism abnormalities and neuroinflammation in dementia patients. In the context of a growing shift toward presymptomatic early diagnosis and disease-modifying interventions, PET molecular imaging agents provide an unprecedented means of quantifying the AD pathophysiological process, monitoring disease progression, ascertaining whether therapies engage their respective brain molecular targets, as well as quantifying pharmacological responses. In the present study, we highlight the most important contributions of PET in describing brain molecular abnormalities in AD.

  16. CTO pathophysiology: how does this affect management?

    Science.gov (United States)

    Irving, John

    2014-05-01

    Chronic total occlusion (CTO) pathophysiology has been described in a few, small studies using post mortem histology, and more recently, in vivo intravascular ultrasound (IVUS) to analyse the constituents of occluded segments. Recent improvements in equipment and techniques have revealed new insights into physical characteristics of occluded coronaries, which in turn enable predictable procedural success. The purpose of this review is to consider the published evidence describing CTO pathophysiology from the perspective of the hybrid algorithm approach to CTO PCI. Literature searches using "Chronic Occlusion", "angioplasty", and" pathology" as keywords. Further searches on "coronary" "collateral", "Viability". Bibliographies were scrutinised for further key publications in an iterative process. Papers describing animal models were excluded.

  17. 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 dilatatio...

  18. Ventricular fibrillation time constant for swine.

    Science.gov (United States)

    Wu, Jiun-Yan; Nimunkar, Amit J; Sun, Hongyu; O'Rourke, Ann; Huebner, Shane; Will, James A; Webster, John G

    2008-10-01

    The strength-duration curve for cardiac excitation can be modeled by a parallel resistor-capacitor circuit that has a time constant. Experiments on six pigs were performed by delivering current from the X26 Taser dart at a distance from the heart to cause ventricular fibrillation (VF). The X26 Taser is an electromuscular incapacitation device (EMD), which generates about 50 kV and delivers a pulse train of about 15-19 pulses s(-1) with a pulse duration of about 150 micros and peak current about 2 A. Similarly a continuous 60 Hz alternating current of the amplitude required to cause VF was delivered from the same distance. The average current and duration of the current pulse were estimated in both sets of experiments. The strength-duration equation was solved to yield an average time constant of 2.87 ms +/- 1.90 (SD). Results obtained may help in the development of safety standards for future electromuscular incapacitation devices (EMDs) without requiring additional animal tests.

  19. Catecholaminergic polymorphic ventricular tachycardia: An exciting new era.

    Science.gov (United States)

    Behere, Shashank P; Weindling, Steven N

    2016-01-01

    Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a highly malignant inheritable cardiac channelopathy. The past decade and a half has provided exciting new discoveries elucidating the genetic etiology and pathophysiology of CPVT. This review of the current literature on CPVT aims to summarize the state of the art in our understanding of the genetic etiology and the molecular pathogenesis of CPVT, and how these relate to our current approach to diagnosis and management. We will also shed light on groundbreaking new work that will continue to refine the management of CPVT in the future. As our knowledge of CPVT continues to grow, further studies will yield a better understanding of the efficacy and pitfalls of established diagnostic approaches and therapies as well as help shape newer diagnostic and treatment strategies. Two separate searches were run on the National Center for Biotechnology Information's (NCBI) website. The first used the medical subject headings (MeSH) database using the term "catecholaminergic polymorphic ventricular tachycardia" that was run on the PubMed database using the age filter (birth to 18 years), and it yielded 58 results. The second search using the MeSH database with the search term "catecholaminergic polymorphic ventricular tachycardia," applying no filters yielded 178 results. The abstracts of all these articles were studied and the articles were categorized and organized. Articles of relevance were read in full. As and where applicable, relevant references and citations from the primary articles were further explored and read in full.

  20. Catecholaminergic polymorphic ventricular tachycardia: An exciting new era

    Directory of Open Access Journals (Sweden)

    Shashank P Behere

    2016-01-01

    Full Text Available Catecholaminergic polymorphic ventricular tachycardia (CPVT is a highly malignant inheritable cardiac channelopathy. The past decade and a half has provided exciting new discoveries elucidating the genetic etiology and pathophysiology of CPVT. This review of the current literature on CPVT aims to summarize the state of the art in our understanding of the genetic etiology and the molecular pathogenesis of CPVT, and how these relate to our current approach to diagnosis and management. We will also shed light on groundbreaking new work that will continue to refine the management of CPVT in the future. As our knowledge of CPVT continues to grow, further studies will yield a better understanding of the efficacy and pitfalls of established diagnostic approaches and therapies as well as help shape newer diagnostic and treatment strategies. Two separate searches were run on the National Center for Biotechnology Information's (NCBI website. The first used the medical subject headings (MeSH database using the term “catecholaminergic polymorphic ventricular tachycardia” that was run on the PubMed database using the age filter (birth to 18 years, and it yielded 58 results. The second search using the MeSH database with the search term “catecholaminergic polymorphic ventricular tachycardia,” applying no filters yielded 178 results. The abstracts of all these articles were studied and the articles were categorized and organized. Articles of relevance were read in full. As and where applicable, relevant references and citations from the primary articles were further explored and read in full.

  1. Hypertrophic Cardiomyopathy: Pathophysiology, Genetics and Invasive Treatment

    NARCIS (Netherlands)

    M. Michels (Michelle)

    2011-01-01

    textabstractHypertrophic cardiomyopathy (HCM) is the most common inheritable cardiac disorder with a phenotypic prevalence of 1:500. It is defined by the presence of left ventricular hypertrophy (LVH) in the absence of loading conditions (hypertension, valve disease) sufficient to cause the observed

  2. Recurrent takotsubo with prolonged QT and torsade de pointes and left ventricular thrombus.

    Science.gov (United States)

    Ahmed, Alaa Eldin K; Serafi, Abdulhalim; Sunni, Nadia S; Younes, Hussein; Hassan, Walid

    2017-01-01

    Takotsubo cardiomyopathy, also known as "takotsubo syndrome," refers to transient apical ballooning syndrome, stress cardiomyopathy, or broken heart syndrome and is a recently recognized syndrome typically characterized by transient and reversible left ventricular dysfunction that develops in the setting of acute severe emotional or physical stress. Increased catecholamine levels have been proposed to play a central role in the pathogenesis of the disease, although the specific pathophysiology of this condition remains to be fully determined. At present, there have been very few reports of recurrent takotsubo cardiomyopathy. In this case report, we present a patient with multiple recurrences of takotsubo syndrome triggered by severe emotional stress that presented with recurrent loss of consciousness, QT prolongation, and polymorphic ventricular tachycardia (torsade de pointes) and left ventricular apical thrombus.

  3. Arterial baroreflex function and left ventricular hypertrophy

    Institute of Scientific and Technical Information of China (English)

    MIAO Chao-Yu; SU Ding-Feng

    2004-01-01

    It is well known that the arterial baroreflex(ABR)plays a key role in the regulation of heart rate and stabilization of blood pressure.Currently,it appears that ABR dysfunction is involved in the pathophysiology of cardiovascular disease states.Since the mid-1990s,a number of studies have been carried out in our laboratory to explore the pathological significance of ABR function in cardiovascular damage.This minireview summarizes our research work on the topic of ABR and left ventricular hypertrophy(LVH).On the basis of discussion concerning the importance of ABR dysfunction in hypertensive LVH and sinoaortic denervation-induced LVH,we advance a new strategy for reversal of LVH,that is,restoration of impaired ABR function.We tested this hypothesis in animal models with ABR deficiency.It was found that improvement of impaird ABR function with long-term treatment of ketanserin or candesartan was accompanied by reversal of LVH.The preliminary results indicate that it is feasible to target ABR for treatment of LVH.

  4. A new look at bronchopulmonary dysplasia: postcapillary pathophysiology and cardiac dysfunction

    Science.gov (United States)

    Malikiwi, Andra; Paul, Eldho; Tan, Kenneth; Menahem, Samuel

    2016-01-01

    Abstract Pulmonary hypertension (PH) and right ventricular function are the focus of cardiovascular effects of bronchopulmonary dysplasia (BPD). We assessed cardiac indexes reflecting systemic afterload and pulmonary venous back pressure as pathophysiologic factors. Cardiac parameters were measured by conventional echocardiography in 20 preterm infants with severe BPD and compared with those of 10 preterm infants with no BPD and 20 healthy term infants. In infants with severe BPD, PH was noted in 5 (25%) by tricuspid regurgitation Doppler jet ≥2.8 m/s and in 15 (75%) by time to peak velocity/right ventricular ejection time valve stroke volume (4.7 ± 0.7 vs. 5.6 ± 0.6 vs. 5.9 ± 0.1; P = 0.002), and myocardial performance index (0.33 ± 0.05 vs. 0.28 ± 0.01 vs. 0.27 ± 0.05; P = 0.03). Left ventricular output was significantly lower in the BPD cohort (183 ± 45 vs. 189 ± 9 vs. 191 ± 32 mL/kg/min; P = 0.03). Altered systemic (left-sided) cardiac function was noted in infants with BPD, which may lead to pulmonary venous congestion contributing to a continued need for respiratory support. PMID:28090292

  5. OSTEOARTHRITIS: A LOOK AT PATHOPHYSIOLOGY AND ...

    African Journals Online (AJOL)

    Correspondence to: Dr. G. O. Oyoo, Department of Clinical Medicine and Therapeutics, School of Medicine, ... Study design: Articles that emphasized the pathogenesis and pathophysiology and new treatment ..... Natural inhibitors capable of directly counteracting ... Etanercept for RA have been tried with little success.

  6. Physiological Coping: A Model for Teaching Pathophysiology

    Science.gov (United States)

    Porth, Carol M.

    1977-01-01

    The author discusses the use of a teaching model she developed for use in a pathophysiology. The model is based on the physiological component of C. Roy's adaptation model, which encourages students to look for physiological cues and apply relevant knowledge in patient care through a problem-solving approach. (TA)

  7. Retinal vein occlusion: pathophysiology and treatment options

    OpenAIRE

    Niral Karia

    2010-01-01

    Niral KariaDepartment of Ophthalmology, Southend Hospital, Prittlewell Chase, Westcliff on Sea, Essex, United KingdomAbstract: This paper reviews the current thinking about retinal vein occlusion. It gives an overview of its pathophysiology and discusses the evidence behind the various established and emerging treatment paradigms.Keywords: central, hemispheric, branch, retinal vein occlusion, visual loss

  8. 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.

  9. Similarities and Differences between the Pathogenesis and Pathophysiology of Diastolic and Systolic Heart Failure

    Directory of Open Access Journals (Sweden)

    Kazuo Komamura

    2013-01-01

    Full Text Available Pathophysiology of heart failure has been considered to be a damaged state of systolic function of the heart followed by a state of low cardiac output that is, systolic heart failure. Even if systolic function is preserved, left ventricular filling in diastole can be impeded and resulted in elevation of filling pressure and symptoms of heart failure. This kind of heart failure is called diastolic heart failure. Nowadays, diastolic heart failure is referred to as heart failure with preserved ejection fraction (HFpEF, whereas systolic heart failure is referred to as heart failure with reduced ejection fraction (HFrEF. In this paper, the similarities and differences between the pathogenesis and pathophysiology of diastolic and systolic heart failure were reviewed. Although diastolic heart failure is a common condition of heart failure worldwide, its pathophysiology has not been sufficiently elucidated. This is thought to be the most significant reason for a lack of established treatment methods for diastolic heart failure. We hope to proceed with future studies on this topic.

  10. Heat stress in growing pigs

    OpenAIRE

    Huynh Thi Thanh Thuy

    2005-01-01

    Compared to other species of farm animals, pigs are more sensitive to high environmental temperatures, because they cannot sweat and do not pant so well. Furthermore, fast-growing lean pigs generate more heat than their congeners living in the wild. This, in combination with confined housing, makes it difficult for these pigs to regulate their heat balance. Heat stressed pigs have low performance, poor welfare, and, by pen fouling, they give higher emissions of odour and ammonia.Above certain...

  11. Chlamydiaceae infections in pig

    Directory of Open Access Journals (Sweden)

    Schautteet Katelijn

    2011-02-01

    Full Text Available Abstract Chlamydiaceae are Gram-negative obligate intracellular bacteria. They are responsible for a broad range of diseases in animals and humans. In pigs, Chlamydia suis, Chlamydia abortus, Chlamydia pecorum and Chlamydia psittaci have been isolated. Chlamydiaceae infections in pigs are associated with different pathologies such as conjunctivitis, pneumonia, pericarditis, polyarthritis, polyserositis, pseudo-membranous or necrotizing enteritis, periparturient dysgalactiae syndrome, vaginal discharge, return to oestrus, abortion, mummification, delivery of weak piglets, increased perinatal and neonatal mortality and inferior semen quality, orchitis, epididymitis and urethritis in boars. However, Chlamydiaceae are still considered as non-important pathogens because reports of porcine chlamydiosis are rare. Furthermore, Chlamydiaceae infections are often unnoticed because tests for Chlamydiaceae are not routinely performed in all veterinary diagnostic laboratories and Chlamydiaceae are often found in association with other pathogens, which are sometimes more easily to detect. However, recent studies have demonstrated that Chlamydiaceae infections in breeding sows, boars and piglets occur more often than thought and are economically important. This paper presents an overview on: the taxonomy of Chlamydiaceae occurring in pigs, diagnostic considerations, epidemiology and pathology of infections with Chlamydiaceae in pigs, public health significance and finally on prevention and treatment of Chlamydiaceae infections in pigs.

  12. Preliminary results of left heart bypass in pigs using a heparin-coated centrifugal pump.

    Science.gov (United States)

    Campanella, C; Cameron, E; Sinclair, C; Feilberg, V L; Hider, C; Prasad, S; Boulton, F; Lamb, D

    1991-08-01

    To assess the feasibility of left ventricular assist without systemic heparinization, we used a commercially available (Sarns 3M) centrifugal pump with tubing set and cannulas, all internally precoated for the purpose of this study with heparin, to bypass the left ventricle in 12 pigs for periods of either 1 or 3 hours. There was no significant activation of clotting and there was no sign of generalized embolization. However, on postmortem studies, 5 kidneys out of 22 examined showed signs of minimal thromboembolism. This experiment shows that artificial left ventricular assist, free of systemic heparinization but using heparin precoating, is feasible and safe, at least for a short period of time.

  13. Citric Acid Cycle Metabolites Predict the Severity of Myocardial Stunning and Mortality in Newborn Pigs

    DEFF Research Database (Denmark)

    Hyldebrandt, Janus Adler; Støttrup, Nicolaj Brejnholt; Frederiksen, Christian Alcaraz

    2016-01-01

    , which so far are undetermined. DESIGN: A total of 28 newborn pigs were instrumented with a microdialysis catheter in the right ventricle, and intercellular citric acid cycle intermediates and adenosine metabolite concentrations were determined at 20-minute intervals. Stunning was induced by 10 cycles...... animals (n = 8), concentrations of succinate (p citric acid cycle intermediates and adenosine metabolites reflects...... the presence of myocardial stunning and predicts mortality in acute noninfarct right ventricular heart failure in newborn pigs. This phenomenon occurs independently of the type of inotrope, suggesting that citric acid cycle intermediates represent potential markers of acute noninfarct heart failure....

  14. Genome editing revolutionize the creation of genetically modified pigs for modeling human diseases.

    Science.gov (United States)

    Yao, Jing; Huang, Jiaojiao; Zhao, Jianguo

    2016-09-01

    Pigs have anatomical, physiological and genomic characteristics that make them highly suitable for modeling human diseases. Genetically modified (GM) pig models of human diseases are critical for studying pathogenesis, treatment, and prevention. The emergence of nuclease-mediated genome editing technology has been successfully employed for engineering of the pig genome, which has revolutionize the creation of GM pig models with highly complex pathophysiologies and comorbidities. In this review, we summarize the progress of recently developed genome editing technologies, including zinc finger nucleases (ZFNs), transcription activator-like effector nucleases (TALENs), and the clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated protein 9 (Cas9), which enable highly efficient and precise introduction of genome modifications into pigs, and tailored disease models that have been generated in various disciplines via genome editing technology. We also summarize the GM pig models that have been generated by conventional transgenic strategies. Additionally, perspectives regarding the application of GM pigs in biomedical research are discussed.

  15. Catheter ablation of a monofocal premature ventricular complex triggering idiopathic ventricular fibrillation.

    Science.gov (United States)

    Takatsuki, S; Mitamura, H; Ogawa, S

    2001-07-01

    A 62 year old man was admitted for evaluation of recurrent episodes of syncope. A surface ECG showed frequent repetitive premature ventricular complexes of right ventricular outflow tract origin. Ventricular fibrillation was inducible by programmed electrical stimulation but otherwise cardiac evaluation was unremarkable. A diagnosis of idiopathic ventricular fibrillation was made and an implantable cardioverter-defibrillator (ICD) was installed. However, spontaneous ventricular fibrillation recurred, requiring repeated ICD discharges. The ventricular fibrillation was reproducibly triggered by a single premature ventricular complex with a specific QRS morphology. Radiofrequency catheter ablation was carried out to eradicate this complex. No ventricular fibrillation has developed after this procedure, and the patient does not require drug treatment.

  16. Rupture of Right Ventricular Free Wall Following Ventricular Septal Rupture in Takotsubo Cardiomyopathy with Right Ventricular Involvement.

    Science.gov (United States)

    Sung, June Min; Hong, Sung Jin; Chung, In Hyun; Lee, Hye Young; Lee, Jae Hoon; Kim, Hyun Jung; Byun, Young Sup; Kim, Byung Ok; Rhee, Kun Joo

    2017-01-01

    Most patients diagnosed with takotsubo cardiomyopathies are expected to almost completely recover, and their prognosis is excellent. However, complications can occur in the acute phase. We present a case of a woman with takotsubo cardiomyopathy with right ventricular involvement who developed a rupture of the right ventricular free wall following ventricular septal rupture, as a consequence of an acute increase in right ventricular afterload by left-to-right shunt. Our case report illustrates that takotsubo cardiomyopathy can be life threatening in the acute phase. Ventricular septal rupture in biventricular takotsubo cardiomyopathy may be a harbinger of cardiac tamponade by right ventricular rupture.

  17. BHA study in pigs.

    Science.gov (United States)

    Würtzen, G; Olsen, P

    1986-01-01

    Butylated hydroxyanisole (BHA) was given to pregnant SPF pigs (Danish Landrace) in doses of 0, 50, 200 and 400 mg/kg body weight/day from mating to day 110 of the gestation period. The BHA was mixed in the diet (pelleted). Caesarean section was performed on gestation day 110. BHA affected neither the reproduction data nor the incidence of defects in the foetuses. Significantly lower weight gain was observed in the group of dams on the highest dose. Absolute and relative organ weights for the liver and thyroid gland showed a dose-related increase. Proliferative and parakeratotic proliferative changes of the stratified epithelium of the stomach were found in both control and treated pigs. In addition, proliferative and parakeratotic changes of the oesophageal epithelium were observed in a few pigs in the two groups on the highest doses. Papillomas were not found, and no changes of the glandular part of the stomach were observed.

  18. The catecholaminergic innervation of the claustrum of the pig.

    Science.gov (United States)

    Pirone, Andrea; Miragliotta, Vincenzo; Ciregia, Federica; Giannessi, Elisabetta; Cozzi, Bruno

    2017-10-01

    Over the past decades, the number of studies employing the pig brain as a model for neurochemical studies has dramatically increased. The key translational features of the pig brain are the similarities with the cortical and subcortical structures of the human brain. In addition, the caudalmost part of the pig claustrum (CL) is characterized by a wide enlargement called posterior puddle, an ideal structure for physiological recordings. Several hypotheses have been proposed for CL function, the key factor being its reciprocal connectivity with most areas of the cerebral cortex and selected subcortical structures. However, afferents from the brainstem could also be involved. The brainstem is the main source of catecholaminergic axons that play an important neuromodulatory action in different brain functions. To study a possible role of the CL in catecholaminergic pathways, we analyzed the presence and the distribution of afferents immunostained with antibodies against tyrosine hydroxylase (TH) and dopamine betahydroxylase (DBH) in the pig CL. Here we show that the CL contains significant TH immunoreactive axons contacting perikarya, whereas projections staining for DBH are very scarce. Our findings hint at the possibility that brainstem catecholaminergic afferents project to the CL, suggesting (i) a possible role of this nucleus in functions controlled by brainstem structures; and, consequently, (ii) its potential involvement in the pathophysiology of neurodegenerative pathologies, including Parkinson's disease (PD). © 2017 Anatomical Society.

  19. Pig design patterns

    CERN Document Server

    Pasupuleti, Pradeep

    2014-01-01

    Pig makes Hadoop programming simple, intuitive, and fun to work with. It removes the complexity from Map Reduce programming by giving the programmer immense power through its flexibility. What used to be extremely lengthy and intricate code written in other high level languages can now be written in almost one tenth of the size using its easy to understand constructs. Pig has proven to be the easiest way to learn how to program Hadoop clusters, as evidenced by its widespread adoption. This comprehensive guide enables readers to readily use design patterns to simplify the creation of complex da

  20. [Pathophysiology of Ataxia in Fisher Syndrome].

    Science.gov (United States)

    Kuwabara, Satoshi

    2016-12-01

    Fisher syndrome is regarded as a peculiar inflammatory neuropathy associated with ophthalmoplegia, ataxia, and areflexia. The disorder is associated with preceding infection, cerebrospinal fluid albumino-cytological dissociation, and spontaneous recovery, and regarded as a variant of Guillain-Barré syndrome. The discovery of anti-GQ1b IgG antibodies led to dramatic advances in understanding the pathophysiology of Fisher syndrome. The lesions in Fisher syndrome are determined by expression of ganglioside GQ1b in the human nervous system. This review article focuses on the pathophysiology of ataxia in Fisher syndrome. Current evidence suggests that antibody attack on Group Ia neurons in the dorsal root ganglia is mainly responsible for the sensory ataxia. Involvement of the muscle spindles might also contribute to the development of ataxia.

  1. Juvenile myoclonic epilepsy: epidemiology, pathophysiology, and management.

    Science.gov (United States)

    Welty, Timothy E

    2006-01-01

    Juvenile myoclonic epilepsy (JME) is a common epilepsy syndrome that begins most frequently in the early teenage years. It is officially classified as a type of idiopathic generalized epilepsy and is often under-recognized or misdiagnosed. This syndrome has a strong genetic component with multiple gene mutations being associated with the clinical presentation. Based upon genetic associations, there may be multiple pathophysiologic mechanisms for the disorder; the pathophysiology has not been clearly defined. A diagnosis of JME is made using the clinical history and EEG findings. Valproic acid is the primary antiepileptic drug (AED) used for JME, but some newer AEDs may be effective alternatives. Selection of an appropriate AED is essential to the proper management of JME, because of the possibility of exacerbation of seizures by some AEDs and the adverse effect profiles of effective drugs. It is important for clinicians to understand JME to correctly diagnose and manage patients with this syndrome.

  2. [The pathophysiology of irritable bowel syndrome].

    Science.gov (United States)

    Zouiten, Mekki Lilia; Karoui, Sami; Boubaker, Jalel; Fekih, Monia; Mechmeche, Rachid; Filali, Azza

    2006-05-01

    The irritable bowel syndrome (IBS) is a frequent gastrointestinal disorder (10 -15% of the population). It is characterized by chronic abdominal pain with modification in the bowel habits. The diagnosis is based of ROME II criteria. The pathophysiology of the SII remains unknown . It result from visceral hypersensitivity with anomalies of the digestive motility. These anomalies are secondary of dysfunction of the brain - gut axis modulated by environmental and the psychosocial factors. The understanding of the pathophysiological mechanisms of the SII and in particular the function of the brain-gut axis will permit a better handling of the patients. Indeed, the present knowledge of the neurotransmitter implied in the communication between the central nervous system and the digestive tract are currently the basis of the new therapies aimed to modulate the mechanisms implicated in the causation of the several symptoms of IBS. These novel pharmacotherapy should reduce the indirect societal and costs of IBS.

  3. [Genomic approach to pathophysiology of rheumatoid arthritis].

    Science.gov (United States)

    Yamada, Ryo

    2012-11-01

    Genetic studies identified multiple genes and polymorphisms that increase risk to develop rheumatoid arthritis. Genomic approach is characterized with its integrative style using mathematical and statistical models. Its main targets include (1)combinatorial effect of multiple genetic and environmental factors, (2)heterogeneity of pathological states and its individuality, and (3)their chronological heterogeneity. Genomic approach will clarify pathophysiology of various diseases along with the progresses in molecular biology and other researches on individual molecules.

  4. Pathophysiology of Non Alcoholic Fatty Liver Disease

    Science.gov (United States)

    Petta, Salvatore; Gastaldelli, Amalia; Rebelos, Eleni; Bugianesi, Elisabetta; Messa, Piergiorgio; Miele, Luca; Svegliati-Baroni, Gianluca; Valenti, Luca; Bonino, Ferruccio

    2016-01-01

    The physiopathology of fatty liver and metabolic syndrome are influenced by diet, life style and inflammation, which have a major impact on the severity of the clinicopathologic outcome of non-alcoholic fatty liver disease. A short comprehensive review is provided on current knowledge of the pathophysiological interplay among major circulating effectors/mediators of fatty liver, such as circulating lipids, mediators released by adipose, muscle and liver tissues and pancreatic and gut hormones in relation to diet, exercise and inflammation. PMID:27973438

  5. Effects of Na+ channel blockers on extrasystolic stimulation-evoked changes in ventricular conduction and repolarization.

    Science.gov (United States)

    Osadchii, Oleg E

    2014-03-01

    Antiarrhythmic agents which belong to class Ia (quinidine) and Ic (flecainide) reportedly increase propensity to ventricular tachyarrhythmia, whereas class Ib agents (lidocaine and mexiletine) are recognized as safe antiarrhythmics. Clinically, tachyarrhythmia is often initiated by a premature ectopic beat, which increases spatial nonuniformities in ventricular conduction and repolarization thus facilitating reentry. This study examined if electrical derangements evoked by premature excitation may be accentuated by flecainide and quinidine, but unchanged by lidocaine and mexiletine, which would explain the difference in their safety profile. In perfused guinea pig hearts, a premature excitation evoked over late repolarization phase was associated with prolonged epicardial activation time, reduced monophasic action potential duration (APD), and increased transepicardial dispersion of the activation time and APD. Flecainide and quinidine increased conduction slowing evoked by extrasystolic stimulation, prolonged APD, and accentuated spatial heterogeneities in ventricular conduction and repolarization associated with premature excitation. Spontaneous episodes of nonsustained monomorphic ventricular tachycardia were observed in 50% of heart preparations exposed to drug infusion. In contrast, lidocaine and mexiletine had no effect on extrasystolic stimulation-evoked changes in ventricular conduction and repolarization or arrhythmic susceptibility. These findings suggest that flecainide and quinidine may promote arrhythmia by exaggerating electrophysiological abnormalities evoked by ectopic beats.

  6. Mechanisms and Clinical Management of Ventricular Arrhythmias following Blunt Chest Trauma

    Directory of Open Access Journals (Sweden)

    Daniel H. Wolbrom

    2016-01-01

    Full Text Available Nonpenetrating, blunt chest trauma is a serious medical condition with varied clinical presentations and implications. This can be the result of a dense projectile during competitive and recreational sports but may also include other etiologies such as motor vehicle accidents or traumatic falls. In this setting, the manifestation of ventricular arrhythmias has been observed both acutely and chronically. This is based on two entirely separate mechanisms and etiologies requiring different treatments. Ventricular fibrillation can occur immediately after chest wall injury (commotio cordis and requires rapid defibrillation. Monomorphic ventricular tachycardia can develop in the chronic stage due to underlying structural heart disease long after blunt chest injury. The associated arrhythmogenic tissue may be complex and provides the necessary substrate to form a reentrant VT circuit. Ventricular tachycardia in the absence of overt structural heart disease appears to be focal in nature with rapid termination during ablation. Regardless of the VT mechanism, patients with recurrent episodes, despite antiarrhythmic medication in the chronic stage following blunt chest injury, are likely to require ablation to achieve VT control. This review article will describe the mechanisms, pathophysiology, and treatment of ventricular arrhythmias that occur in both the acute and chronic stages following blunt chest trauma.

  7. BHA STUDY IN PIGS

    DEFF Research Database (Denmark)

    Würtzen, G.; Olsen, P.

    1986-01-01

    Butylated hydroxyanisole (BHA) was given to pregnant SPF pigs (Danish Landrace) in doses of 0, 50, 200 and 400 mg/kg body weight/day from mating to day 110 of the gestation period. The BHA was mixed in the diet (pelleted). Caesarean section was performed on gestation day 110. BHA affected neither...

  8. Measuring emotions in pigs

    NARCIS (Netherlands)

    Reimert, I.

    2014-01-01

    Inonge Reimert monitored pig behaviors in positive and negative emotional states and compared the results. For her research, she used The Observer XT for behavioral annotation. She found very different behaviors to be associated with the two situations, such as play and tail wagging in the positive

  9. A Simple "Pig" Game

    Science.gov (United States)

    Johnson, Roger W.

    2008-01-01

    Our pig game involves a series of tosses of a die with the possibility of a player's score improving with each additional toss. With each additional toss, however, there is also the chance of losing the entire score accumulated so far. Two different strategies for deciding how many tosses a player should attempt are developed and then compared in…

  10. Genetics Home Reference: arrhythmogenic right ventricular cardiomyopathy

    Science.gov (United States)

    ... Twitter Home Health Conditions ARVC arrhythmogenic right ventricular cardiomyopathy Printable PDF Open All Close All Enable Javascript ... the expand/collapse boxes. Description Arrhythmogenic right ventricular cardiomyopathy ( ARVC ) is a form of heart disease that ...

  11. Hemoglobin A1c and arterial and ventricular stiffness in older adults.

    Directory of Open Access Journals (Sweden)

    Susan J Zieman

    Full Text Available OBJECTIVE: Arterial and ventricular stiffening are characteristics of diabetes and aging which confer significant morbidity and mortality; advanced glycation endproducts (AGE are implicated in this stiffening pathophysiology. We examined the association between HbA(1c, an AGE, with arterial and ventricular stiffness measures in older individuals without diabetes. RESEARCH DESIGN & METHODS: Baseline HbA(1c was measured in 830 participants free of diabetes defined by fasting glucose or medication use in the Cardiovascular Health Study, a population-based cohort study of adults aged ≥ 65 years. We performed cross-sectional analyses using baseline exam data including echocardiography, ankle and brachial blood pressure measurement, and carotid ultrasonography. We examined the adjusted associations between HbA(1c and multiple arterial and ventricular stiffness measures by linear regression models and compared these results to the association of fasting glucose (FG with like measures. RESULTS: HbA(1c was correlated with fasting and 2-hour postload glucose levels (r = 0.21; p<0.001 for both and positively associated with greater body-mass index and black race. In adjusted models, HbA(1c was not associated with any measure of arterial or ventricular stiffness, including pulse pressure (PP, carotid intima-media thickness, ankle-brachial index, end-arterial elastance, or left ventricular mass (LVM. FG levels were positively associated with systolic, diastolic and PP and LVM. CONCLUSIONS: In this sample of older adults without diabetes, HbA(1c was not associated with arterial or ventricular stiffness measures, whereas FG levels were. The role of AGE in arterial and ventricular stiffness in older adults may be better assessed using alternate AGE markers.

  12. Recognizing Pulmonary Hypertension and Right Ventricular Dysfunction in Heart Failure.

    Science.gov (United States)

    Lala, Anuradha; Pinney, Sean P

    2016-01-01

    Pulmonary hypertension (PH) in the setting of left heart disease (LHD) or heart failure (HF) is the most common form of PH, yet its prevalence is underappreciated. Varying terminology possibly leads to misconceptions in pathophysiology, diagnosis and management. The accurate diagnosis of PH due to LHD is contingent upon hemodynamic assessment via right heart catheterization, however due to limitations in access, comprehensive echocardiography and integrative scoring systems are frequently used. When present in the setting of PH due to LHD, right ventricular dysfunction (RVD) confers a poor clinical prognosis. The management of RVD is directed towards treating underlying HF and/or valvular disease. Implantable hemodynamic monitors may offer opportunity to obtain longitudinal information to increase diagnostic accuracy as well as monitor the effect of treatment of PH in the setting of HF with and without the presence of RVD. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Catheter ablation of a polymorphic ventricular tachycardia inducing monofocal premature ventricular complex.

    Science.gov (United States)

    Uemura, Takashi; Yamabe, Hiroshige; Tanaka, Yasuaki; Morihisa, Kenji; Kawano, Hiroaki; Kaikita, Koichi; Sumida, Hitoshi; Sugiyama, Seigo; Ogawa, Hisao

    2008-01-01

    Ventricular tachycardia originating from the right ventricular outflow tract (RVOT) is considered benign, but sometimes it causes polymorphic ventricular tachycardia and ventricular fibrillation, resulting in sudden cardiac death. A 58-year-old woman without structural heart disease was admitted for evaluation of recurrent episodes of syncope. Surface ECG showed frequent repetitive premature ventricular contraction (PVC) of RVOT origin. Polymorphic ventricular tachycardia triggered by the same PVC was documented by Holter ECG during an episode of syncope. Radiofrequency catheter ablation was performed to eradicate this PVC. No polymorphic ventricular tachycardia has developed after the procedure, and the patient has had no recurrence of syncope.

  14. 21 CFR 882.4060 - Ventricular cannula.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ventricular cannula. 882.4060 Section 882.4060...) MEDICAL DEVICES NEUROLOGICAL DEVICES Neurological Surgical Devices § 882.4060 Ventricular cannula. (a) Identification. A ventricular cannula is a device used to puncture the ventricles of the brain for aspiration...

  15. 21 CFR 882.4100 - Ventricular catheter.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ventricular catheter. 882.4100 Section 882.4100...) MEDICAL DEVICES NEUROLOGICAL DEVICES Neurological Surgical Devices § 882.4100 Ventricular catheter. (a) Identification. A ventricular catheter is a device used to gain access to the cavities of the brain for...

  16. The pathophysiology of lifelong premature ejaculation.

    Science.gov (United States)

    Waldinger, Marcel D

    2016-08-01

    For many decades it has been thought that lifelong premature ejaculation (PE) is only characterized by persistent early ejaculations. Despite enormous progress of in vivo animal research, and neurobiological, genetic and pharmacological research in men with lifelong PE, our current understanding of the mechanisms behind early ejaculations is far from complete. The new classification of PE into four PE subtypes has shown that the symptomatology of lifelong PE strongly differs from acquired PE, subjective PE and variable PE. The phenotype of lifelong PE and therefore also the pathophysiology of lifelong PE is much more complex. A substantial number of men with lifelong PE not only have PE, but also premature erection and premature penile detumescence as part of an acute hypertonic or hypererotic state when engaged in an erotic situation or when making love. As both erectio praecox, ejaculatio praecox, detumescentia praecox, and the hypererotic state are part of the phenotype lifelong PE, it is argued that lifelong PE is not only a disturbance of the timing of ejaculation but also a disturbance of the timing of erection, detumescence and arousal. Since 1998, the pathophysiology of lifelong PE was thought to be mainly mediated by the central serotonergic system in line with genetic polymorphisms of specific serotonergic genes. However, by accepting that lifelong PE is characterized by the reversible hypertonic state the hypothesis of mainly serotonergic dysfunction is no longer tenable. Instead, it has been postulated that the pathophysiology of lifelong PE is mediated by a very complex interplay of central and peripheral serotonergic, dopaminergic, oxytocinergic, endocrinological, genetic and probably also epigenetic factors. Progress in research of lifelong PE can only be accomplished when a stopwatch is used to measure the IELT and the cut-off point of 1 minute for the definition of lifelong PE is maintained. Current use of validated questionnaires, neglect of

  17. The pathophysiology of lifelong premature ejaculation

    Science.gov (United States)

    2016-01-01

    For many decades it has been thought that lifelong premature ejaculation (PE) is only characterized by persistent early ejaculations. Despite enormous progress of in vivo animal research, and neurobiological, genetic and pharmacological research in men with lifelong PE, our current understanding of the mechanisms behind early ejaculations is far from complete. The new classification of PE into four PE subtypes has shown that the symptomatology of lifelong PE strongly differs from acquired PE, subjective PE and variable PE. The phenotype of lifelong PE and therefore also the pathophysiology of lifelong PE is much more complex. A substantial number of men with lifelong PE not only have PE, but also premature erection and premature penile detumescence as part of an acute hypertonic or hypererotic state when engaged in an erotic situation or when making love. As both erectio praecox, ejaculatio praecox, detumescentia praecox, and the hypererotic state are part of the phenotype lifelong PE, it is argued that lifelong PE is not only a disturbance of the timing of ejaculation but also a disturbance of the timing of erection, detumescence and arousal. Since 1998, the pathophysiology of lifelong PE was thought to be mainly mediated by the central serotonergic system in line with genetic polymorphisms of specific serotonergic genes. However, by accepting that lifelong PE is characterized by the reversible hypertonic state the hypothesis of mainly serotonergic dysfunction is no longer tenable. Instead, it has been postulated that the pathophysiology of lifelong PE is mediated by a very complex interplay of central and peripheral serotonergic, dopaminergic, oxytocinergic, endocrinological, genetic and probably also epigenetic factors. Progress in research of lifelong PE can only be accomplished when a stopwatch is used to measure the IELT and the cut-off point of 1 minute for the definition of lifelong PE is maintained. Current use of validated questionnaires, neglect of

  18. Lafora disease: epidemiology, pathophysiology and management.

    LENUS (Irish Health Repository)

    Monaghan, Thomas S

    2010-07-01

    Lafora disease is a rare, fatal, autosomal recessive, progressive myoclonic epilepsy. It may also be considered as a disorder of carbohydrate metabolism because of the formation of polyglucosan inclusion bodies in neural and other tissues due to abnormalities of the proteins laforin or malin. The condition is characterized by epilepsy, myoclonus and dementia. Diagnostic findings on MRI and neurophysiological testing are not definitive and biopsy or genetic studies may be required. Therapy in Lafora disease is currently limited to symptomatic management of the epilepsy, myoclonus and intercurrent complications. With a greater understanding of the pathophysiological processes involved, there is justified hope for future therapies.

  19. Pathophysiology of muscle contractures in cerebral palsy.

    Science.gov (United States)

    Mathewson, Margie A; Lieber, Richard L

    2015-02-01

    Patients with cerebral palsy present with a variety of adaptations to muscle structure and function. These pathophysiologic symptoms include functional deficits such as decreased force production and range of motion, in addition to changes in muscle structure such as decreased muscle belly size, increased sarcomere length, and altered extracellular matrix structure and composition. On a cellular level, patients with cerebral palsy have fewer muscle stem cells, termed satellite cells, and altered gene expression. Understanding the nature of these changes may present opportunities for the development of new muscle treatment therapies.

  20. Heatstroke Pathophysiology: The Energy Depletion Model

    Science.gov (United States)

    1989-06-12

    Pathophysiology: The Energy Depletion Model Roger W. Hubbard, Ph.D., Director Heat Research Division U. S. Army Research Institute of Environmental...Medicine Natick, MA 01760-5007 USA Send correspondence to: Roger W. Hubbard, Ph.D. Director Heat Research Division USARIEM Kansas St Natick, MA 01760...The NaK-Pump. Part B: Celular Asoects J.C. Skou, J.G. Normy, A.B. Maunsback, and M. Esmann (Eds) New York: Alan R. Uss, 1988, pp. 171-194. 54: Lewis

  1. Pathophysiology of the anorexia of aging.

    Science.gov (United States)

    Morley, John E

    2013-01-01

    Anorexia represents a major problem for older persons leading to weight loss, sarcopenia, functional decline, and mortality. There is increasing information on the pathophysiological mechanisms that lead to anorexia. Increasing evidence has shown the importance of gastrointestinal hormones (ghrelin, cholecystokinin, and glucagon-like peptide) and adipokines in producing the anorexia of aging. Numerous neurotransmitters have been shown to be involved in this aging anorexia, but evidence in humans is lacking. The early recognition of anorexia of aging is important to allow intervention and prevent functional deterioration in older persons. Screening tests for anorexia have been developed. New approaches to managing anorexia are being tested.

  2. Rho kinases in cardiovascular physiology and pathophysiology.

    Science.gov (United States)

    Loirand, Gervaise; Guérin, Patrice; Pacaud, Pierre

    2006-02-17

    Rho kinases (ROCKs) are the first and the best-characterized effectors of the small G-protein RhoA. In addition to their effect on actin organization, or through this effect, ROCKs have been found to regulate a wide range of fundamental cell functions such as contraction, motility, proliferation, and apoptosis. Abnormal activation of the RhoA/ROCK pathway has been observed in major cardiovascular disorders such as atherosclerosis, restenosis, hypertension, pulmonary hypertension, and cardiac hypertrophy. This review, based on recent molecular, cellular, and animal studies, focuses on the current understanding of ROCK signaling and its roles in cardiovascular physiology and pathophysiology.

  3. [Pathophysiology and classification of pulmonary hypertension].

    Science.gov (United States)

    Sládková, H; Jansa, P; Susa, Z; Aschermann, M

    2004-09-01

    Pulmonary hypertension is present when the mean pulmonary pressure is increased above 25 mm Hg in a rest or above 30 mm Hg during exercise. It is possible to divide it from different point of view. Well known is pathophysiologic classification and Venice classification suggested by WHO symposium 2003. The rise of arterial pulmonary pressure is caused by three essential abnormalities, these are elevated pulmonary vascular resistance, blood flow and pulmonary artery wedge pressure. Vasoconstriction, remodeling of vessels and in situ trombosis are pathogenetic mechanism which contribute to rise of pulmonary hypertension.

  4. Pathophysiology of osteoporosis: new mechanistic insights.

    Science.gov (United States)

    Armas, Laura A G; Recker, Robert R

    2012-09-01

    Understanding of the pathophysiology of osteoporosis has evolved to include compromised bone strength and skeletal fragility caused by several factors: (1) defects in microarchitecture of trabeculae, (2) defective intrinsic material properties of bone tissue, (3) defective repair of microdamage from normal daily activities, and (4) excessive bone remodeling rates. These factors occur in the context of age-related bone loss. Clinical studies of estrogen deprivation, antiresorptives, mechanical loading, and disuse have helped further knowledge of the factors affecting bone quality and the mechanisms that underlie them. This progress has led to several new drug targets in the treatment of osteoporosis.

  5. Recent Advances on Pathophysiology, Diagnostic and Therapeutic Insights in Cardiac Dysfunction Induced by Antineoplastic Drugs

    Directory of Open Access Journals (Sweden)

    Marilisa Molinaro

    2015-01-01

    Full Text Available Along with the improvement of survival after cancer, cardiotoxicity due to antineoplastic treatments has emerged as a clinically relevant problem. Potential cardiovascular toxicities due to anticancer agents include QT prolongation and arrhythmias, myocardial ischemia and infarction, hypertension and/or thromboembolism, left ventricular (LV dysfunction, and heart failure (HF. The latter is variable in severity, may be reversible or irreversible, and can occur soon after or as a delayed consequence of anticancer treatments. In the last decade recent advances have emerged in clinical and pathophysiological aspects of LV dysfunction induced by the most widely used anticancer drugs. In particular, early, sensitive markers of cardiac dysfunction that can predict this form of cardiomyopathy before ejection fraction (EF is reduced are becoming increasingly important, along with novel therapeutic and cardioprotective strategies, in the attempt of protecting cardiooncologic patients from the development of congestive heart failure.

  6. Recent Advances on Pathophysiology, Diagnostic and Therapeutic Insights in Cardiac Dysfunction Induced by Antineoplastic Drugs

    Science.gov (United States)

    Molinaro, Marilisa; Marone, Giancarlo; Abete, Pasquale; Di Lisa, Fabio; De Placido, Sabino; Bonaduce, Domenico; Tocchetti, Carlo G.

    2015-01-01

    Along with the improvement of survival after cancer, cardiotoxicity due to antineoplastic treatments has emerged as a clinically relevant problem. Potential cardiovascular toxicities due to anticancer agents include QT prolongation and arrhythmias, myocardial ischemia and infarction, hypertension and/or thromboembolism, left ventricular (LV) dysfunction, and heart failure (HF). The latter is variable in severity, may be reversible or irreversible, and can occur soon after or as a delayed consequence of anticancer treatments. In the last decade recent advances have emerged in clinical and pathophysiological aspects of LV dysfunction induced by the most widely used anticancer drugs. In particular, early, sensitive markers of cardiac dysfunction that can predict this form of cardiomyopathy before ejection fraction (EF) is reduced are becoming increasingly important, along with novel therapeutic and cardioprotective strategies, in the attempt of protecting cardiooncologic patients from the development of congestive heart failure. PMID:26583088

  7. Cardiac MR Elastography: Comparison with left ventricular pressure measurement

    Directory of Open Access Journals (Sweden)

    Samani Abbas

    2009-11-01

    Full Text Available Abstract Purpose of study To compare magnetic resonance elastography (MRE with ventricular pressure changes in an animal model. Methods Three pigs of different cardiac physiology (weight, 25 to 53 kg; heart rate, 61 to 93 bpm; left ventricular [LV] end-diastolic volume, 35 to 70 ml were subjected to invasive LV pressure measurement by catheter and noninvasive cardiac MRE. Cardiac MRE was performed in a short-axis view of the heart and applying a 48.3-Hz shear-wave stimulus. Relative changes in LV-shear wave amplitudes during the cardiac cycle were analyzed. Correlation coefficients between wave amplitudes and LV pressure as well as between wave amplitudes and LV diameter were determined. Results A relationship between MRE and LV pressure was observed in all three animals (R2 ≥ 0.76. No correlation was observed between MRE and LV diameter (R2 ≤ 0.15. Instead, shear wave amplitudes decreased 102 ± 58 ms earlier than LV diameters at systole and amplitudes increased 175 ± 40 ms before LV dilatation at diastole. Amplitude ratios between diastole and systole ranged from 2.0 to 2.8, corresponding to LV pressure differences of 60 to 73 mmHg. Conclusion Externally induced shear waves provide information reflecting intraventricular pressure changes which, if substantiated in further experiments, has potential to make cardiac MRE a unique noninvasive imaging modality for measuring pressure-volume function of the heart.

  8. Facts about Ventricular Septal Defect

    Science.gov (United States)

    ... Living With Heart Defects Data & Statistics Tracking & Research Articles & Key Findings Free Materials Multimedia and Tools Links to Other Websites Information For... Media Policy Makers Facts about Ventricular Septal Defect Language: English Español (Spanish) Recommend on Facebook Tweet Share Compartir ...

  9. The guinea-pig

    DEFF Research Database (Denmark)

    Andersen, Klaus Ejner; Maibach, H I; Anjo, M D

    1980-01-01

    14C ring-labelled hydrocortisone, testosterone and benzoic acid dissolved in acetone were applied to the backs of guinea-pigs (4 microgram/cm2). Percutaneous absorption was quantified by following the excretion of tracer in urine and faeces for 5 days. Absorption of hydrocortisone and benzoic acid...... was 2.4% (s.d. = 0.5; n = 3) and 31.4% (s.d. = 9.1; n = 3) of the applied dose respectively, similar to published human absorption data. Testosterone was absorbed to a greater extent in guinea-pigs (34.9% +/- 5.4; n = 5) than man. A thioglycollate based depilatory cream significantly increased the skin...

  10. The pathophysiology of intrahepatic cholestasis of pregnancy.

    Science.gov (United States)

    Dixon, Peter H; Williamson, Catherine

    2016-04-01

    A number of liver disorders are specific to pregnancy. Amongst these, intrahepatic cholestasis of pregnancy (ICP), also known as obstetric cholestasis (OC), is the commonest, affecting approximately 1 in 140 UK pregnancies. Patients commonly present in the third trimester with severe pruritus and deranged serum liver tests; bile acids are elevated, in severe cases >40 μmol/L. Although the disease is considered relatively benign for the mother, increased rates of adverse fetal outcomes, including stillbirth, are associated with ICP. As our knowledge of the mechanisms underlying bile acid homeostasis has advanced in the last 15 years our understanding of ICP has grown, in particular with respect to genetic influences on susceptibility to the disease, the role of reproductive hormones and their metabolites and the possible identity of the pruritic agents. In this review, we will describe recent advances in the understanding of this condition with a particular emphasis on how aspects of genetic and reproductive hormone involvement in pathophysiology have been elucidated. We also review recent developments regarding our knowledge of placental and fetal pathophysiology and the long-term health consequences for the mother and child. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  11. Inflammation in the pathophysiology of essential hypertension.

    Science.gov (United States)

    Montecucco, Fabrizio; Pende, Aldo; Quercioli, Alessandra; Mach, François

    2011-01-01

    In spite of the huge amount of research recently performed in this area, the pathogenesis of human hypertension remains elusive. Thus, hypertension has to be defined as "essential" for the majority of patients with high blood pressure. Given the lack of animal models useful to investigate essential hypertension, we analyze and discuss both clinical and basic research studies indicating that essential hypertension should be considered as a potential multifactorial inflammatory disease. The pathophysiology of essential hypertension might result from interactions between genetic and environmental factors. Morphological abnormalities in the renal parenchyma and arteries have also been shown to determine hypertension. Inflammatory processes might induce renal vasoconstriction, ischemia and injury that can sustain systemic hypertension. Arterial and tubulointerstitial infiltration of inflammatory cells in response to renal damage might further increase renal and vascular alterations through the production of oxidants and other soluble inflammatory mediators. The present review gives an update regarding the latest research on the possible direct role of inflammation in the pathophysiology of essential hypertension.

  12. Eosinophilic esophagitis: From pathophysiology to treatment.

    Science.gov (United States)

    D'Alessandro, Alessandra; Esposito, Dario; Pesce, Marcella; Cuomo, Rosario; De Palma, Giovanni Domenico; Sarnelli, Giovanni

    2015-11-15

    Eosinophilic esophagitis (EoE) is a chronic immune disease, characterized by a dense eosinophilic infiltrate in the esophagus, leading to bolus impaction and reflux-like symptoms. Traditionally considered a pediatric disease, the number of adult patients with EoE is continuously increasing, with a relatively higher incidence in western countries. Dysphagia and food impaction represent the main symptoms complained by patients, but gastroesophageal reflux-like symptoms may also be present. Esophageal biopsies are mandatory for the diagnosis of EoE, though clinical manifestations and proton pump inhibitors responsiveness must be taken into consideration. The higher prevalence of EoE in patients suffering from atopic diseases suggests a common background with allergy, however both the etiology and pathophysiology are not completely understood. Elimination diets are considered the first-line therapy in children, but this approach appears less effective in adults patients, who often require steroids; despite medical treatments, EoE is complicated in some cases by esophageal stricture and stenosis, that require additional endoscopic treatments. This review summarizes the evidence on EoE pathophysiology and illustrates the safety and efficacy of the most recent medical and endoscopic treatments.

  13. Pathophysiology and management of multivalvular disease

    Science.gov (United States)

    Unger, Philippe; Clavel, Marie-Annick; Lindman, Brian R.; Mathieu, Patrick; Pibarot, Philippe

    2016-01-01

    Multivalvular disease (MVD) is a common condition with a complex pathophysiology, dependent on the specific combination of valve lesions. Diagnosis is challenging as several echocardiographic methods commonly used for the assessment of stenosis or regurgitation have been validated only in patients with single valve disease. Decisions about the timing and type of treatment should be made by a multidisciplinary heart valve team, on a case-by-case basis. Several factors should be considered, including the severity and consequences of the MVD, the patient’s life expectancy and comorbidities, the surgical risk associated with combined valve procedures, the long-term risk of morbidity and mortality associated with multiple valve prostheses, and the likelihood and risk of reoperation. The introduction of transcatheter valve therapies into clinical practice has provided new treatment options for patients with MVD, and decision-making algorithms on how to combine surgical and percutaneous treatment options are evolving rapidly. In this Review, we discuss the pathophysiology, diagnosis, and treatment of MVD, focussing on the combination of valve pathologies that are most often encountered in clinical practice. PMID:27121305

  14. Endocrine FGFs: evolution, physiology, pathophysiology, and pharmacotherapy

    Directory of Open Access Journals (Sweden)

    Nobuyuki eItoh

    2015-09-01

    Full Text Available The human fibroblast growth factor (FGF family comprises 22 structurally related polypeptides that play crucial roles in neuronal functions, development, and metabolism. FGFs are classified as intracrine, paracrine, and endocrine FGFs based on their action mechanisms. Paracrine and endocrine FGFs are secreted signaling molecules by acting via cell-surface FGF receptors (FGFRs. Paracrine FGFs require heparan sulfate as a co-factor for FGFRs. In contrast, endocrine FGFs, comprising FGF19, FGF21, and FGF23, require α−Klotho or β−Klotho as a co-factor for FGFRs. Endocrine FGFs, which are specific to vertebrates, lost heparan sulfate-binding affinity and acquired a systemic signaling system with αKlotho or βKlotho during early vertebrate evolution. The phenotypes of endocrine FGF knockout mice indicate that they play roles in metabolism including bile acid, energy, and phosphate/active vitamin D metabolism. Accumulated evidence for the involvement of endocrine FGFs in human genetic and metabolic diseases also indicates their pathophysiological roles in metabolic diseases, potential risk factors for metabolic diseases, and useful biomarkers for metabolic diseases. The therapeutic utility of endocrine FGFs is currently being developed. These findings provide new insights into the physiological and pathophysiological roles of endocrine FGFs and potential diagnostic and therapeutic strategies for metabolic diseases.

  15. Guinea pig maximization test

    DEFF Research Database (Denmark)

    Andersen, Klaus Ejner

    1985-01-01

    Guinea pig maximization tests (GPMT) with chlorocresol were performed to ascertain whether the sensitization rate was affected by minor changes in the Freund's complete adjuvant (FCA) emulsion used. Three types of emulsion were evaluated: the oil phase was mixed with propylene glycol, saline with...... to the saline/oil emulsion. Placing of the challenge patches affected the response, as simultaneous chlorocresol challenge on the flank located 2 cm closer to the abdomen than the usual challenge site gave decreased reactions....

  16. The Pig PeptideAtlas

    DEFF Research Database (Denmark)

    Hesselager, Marianne Overgaard; Codrea, Marius; Sun, Zhi;

    2016-01-01

    underrepresented in existing repositories. We here present a significantly improved build of the Pig PeptideAtlas, which includes pig proteome data from 25 tissues and three body fluid types mapped to 7139 canonical proteins. The content of the Pig PeptideAtlas reflects actively ongoing research within...... the veterinary proteomics domain, and this article demonstrates how the expression of isoform-unique peptides can be observed across distinct tissues and body fluids. The Pig PeptideAtlas is a unique resource for use in animal proteome research, particularly biomarker discovery and for preliminary design of SRM...

  17. Xenotransplantation and pig endogenous retroviruses.

    Science.gov (United States)

    Magre, Saema; Takeuchi, Yasuhiro; Bartosch, Birke

    2003-01-01

    Xenotransplantation, in particular transplantation of pig cells, tissues and organs into human patients, may alleviate the current shortage of suitable allografts available for human transplantation. This overview addresses the physiological, immunological and virological factors considered with regard to xenotransplantation. Among the issues reviewed are the merits of using pigs as xenograft source species, the compatibility of pig and human organ physiology and the immunological hindrances with regard to the various types of rejection and attempts at abrogating rejection. Advances in the prevention of pig organ rejection by creating genetically modified pigs that are more suited to the human microenvironment are also discussed. Finally, with regard to virology, possible zoonotic infections emanating from pigs are reviewed, with special emphasis on the pig endogenous retrovirus (PERV). An in depth account of PERV studies, comprising their discovery as well as recent knowledge of the virus, is given. To date, all retrospective studies on patients with pig xenografts have shown no evidence of PERV transmission, however, many factors make us interpret these results with caution. Although the lack of PERV infection in xenograft recipients up to now is encouraging, more basic research and controlled animal studies that mimic the pig to human xenotransplantation setting more closely are required for safety assessment.

  18. Pharmacologically induced long QT type 2 can be rescued by activation of IKs with benzodiazepine R-L3 in isolated guinea pig cardiomyocytes

    DEFF Research Database (Denmark)

    Nissen, Jakob Dahl; Diness, Jonas Goldin; Diness, Thomas Goldin

    2009-01-01

    of this study was to evaluate potential antiarrhythmic effects of compound induced IKs activation using the benzodiazepine L-364,373 (R-L3). Ventricular myocytes from guinea pigs were isolated and whole-cell current clamping was performed at 35 degrees C. It was found that 1 microM R-L3 significantly reduced...

  19. Plasma proteome profiles associated with diet-induced metabolic syndrome and the early onset of metabolic syndrome in a pig model.

    Science.gov (United States)

    te Pas, Marinus F W; Koopmans, Sietse-Jan; Kruijt, Leo; Calus, Mario P L; Smits, Mari A

    2013-01-01

    Obesity and related diabetes are important health threatening multifactorial metabolic diseases and it has been suggested that 25% of all diabetic patients are unaware of their patho-physiological condition. Biomarkers for monitoring and control are available, but early stage predictive biomarkers enabling prevention of these diseases are still lacking. We used the pig as a model to study metabolic disease because humans and pigs share a multitude of metabolic similarities. Diabetes was chemically induced and control and diabetic pigs were either fed a high unsaturated fat (Mediterranean) diet or a high saturated fat/cholesterol/sugar (cafeteria) diet. Physiological parameters related to fat metabolism and diabetes were measured. Diabetic pigs' plasma proteome profiles differed more between the two diets than control pigs plasma proteome profiles. The expression levels of several proteins correlated well with (patho)physiological parameters related to the fat metabolism (cholesterol, VLDL, LDL, NEFA) and diabetes (Glucose) and to the diet fed to the animals. Studying only the control pigs as a model for metabolic syndrome when fed the two diets showed correlations to the same parameters but now more focused on insulin, glucose and abdominal fat depot parameters. We conclude that proteomic profiles can be used as a biomarker to identify pigs with developing metabolic syndrome (prediabetes) and diabetes when fed a cafeteria diet. It could be developed into a potential biomarkers for the early recognition of metabolic diseases.

  20. Plasma proteome profiles associated with diet-induced metabolic syndrome and the early onset of metabolic syndrome in a pig model.

    Directory of Open Access Journals (Sweden)

    Marinus F W te Pas

    Full Text Available Obesity and related diabetes are important health threatening multifactorial metabolic diseases and it has been suggested that 25% of all diabetic patients are unaware of their patho-physiological condition. Biomarkers for monitoring and control are available, but early stage predictive biomarkers enabling prevention of these diseases are still lacking. We used the pig as a model to study metabolic disease because humans and pigs share a multitude of metabolic similarities. Diabetes was chemically induced and control and diabetic pigs were either fed a high unsaturated fat (Mediterranean diet or a high saturated fat/cholesterol/sugar (cafeteria diet. Physiological parameters related to fat metabolism and diabetes were measured. Diabetic pigs' plasma proteome profiles differed more between the two diets than control pigs plasma proteome profiles. The expression levels of several proteins correlated well with (pathophysiological parameters related to the fat metabolism (cholesterol, VLDL, LDL, NEFA and diabetes (Glucose and to the diet fed to the animals. Studying only the control pigs as a model for metabolic syndrome when fed the two diets showed correlations to the same parameters but now more focused on insulin, glucose and abdominal fat depot parameters. We conclude that proteomic profiles can be used as a biomarker to identify pigs with developing metabolic syndrome (prediabetes and diabetes when fed a cafeteria diet. It could be developed into a potential biomarkers for the early recognition of metabolic diseases.

  1. Passive ventricular mechanics modelling using MRI of structure and function.

    Science.gov (United States)

    Wang, V Y; Lam, H I; Ennis, D B; Young, A A; Nash, M P

    2008-01-01

    Patients suffering from dilated cardiomyopathy or myocardial infarction can develop left ventricular (LV) diastolic impairment. The LV remodels its structure and function to adapt to pathophysiological changes in geometry and loading conditions and this remodeling process can alter the passive ventricular mechanics. In order to better understand passive ventricular mechanics, a LV finite element model was developed to incorporate physiological and mechanical information derived from in vivo magnetic resonance imaging (MRI) tissue tagging, in vivo LV cavity pressure recording and ex vivo diffusion tensor MRI (DTMRI) of a canine heart. MRI tissue tagging enables quantitative evaluation of cardiac mechanical function with high spatial and temporal resolution, whilst the direction of maximum water diffusion (the primary eigenvector) in each voxel of a DTMRI directly correlates with the myocardial fibre orientation. This model was customized to the geometry of the canine LV during diastasis by fitting the segmented epicardial and endocardial surface data from tagged MRI using nonlinear finite element fitting techniques. Myofibre orientations, extracted from DTMRI of the same heart, were incorporated into this geometric model using a free form deformation methodology. Pressure recordings, temporally synchronized to the tissue tagging MRI data, were used to simulate the LV deformation during diastole. Simulation of the diastolic LV mechanics allowed us to estimate the stiffness of the passive LV myocardium based on kinematic data obtained from tagged MRI. This integrated physiological model will allow more insight into the regional passive diastolic mechanics of the LV on an individualized basis, thereby improving our understanding of the underlying structural basis of mechanical dysfunction in pathological conditions.

  2. Comparative analyses of QTLs influencing obesity and metabolic phenotypes in pigs and humans

    DEFF Research Database (Denmark)

    Pant, Sameer Dinkar; Karlskov-Mortensen, Peter; Jacobsen, Mette Juul;

    2015-01-01

    The pig is a well-known animal model used to investigate genetic and mechanistic aspects of human disease biology. They are particularly useful in the context of obesity and metabolic diseases because other widely used models (e.g. mice) do not completely recapitulate key pathophysiological...... features associated with these diseases in humans. Therefore, we established a F2 pig resource population (n = 564) designed to elucidate the genetics underlying obesity and metabolic phenotypes. Segregation of obesity traits was ensured by using breeds highly divergent with respect to obesity traits...... in the parental generation. Several obesity and metabolic phenotypes were recorded (n = 35) from birth to slaughter (242 ± 48 days), including body composition determined at about two months of age (63 ± 10 days) via dual-energy x-ray absorptiometry (DXA) scanning. All pigs were genotyped using Illumina Porcine...

  3. Structured prediction for differentiating between normal rhythms, ventricular tachycardia, and ventricular fibrillation in the ECG.

    Science.gov (United States)

    Alwan, Yaqub; Cvetkovic, Zoran; Curtis, Michael

    2015-01-01

    Recent studies have been performed on feature selection for diagnostics between non-ventricular rhythms and ventricular arrhythmias, or between non-ventricular fibrillation and ventricular fibrillation. However they did not assess classification directly between non-ventricular rhythms, ventricular tachycardia and ventricular fibrillation, which is important in both a clinical setting and preclinical drug discovery. In this study it is shown that in a direct multiclass setting, the selected features from these studies are not capable at differentiating between ventricular tachycardia and ventricular fibrillation. A high dimensional feature space, Fourier magnitude spectra, is proposed for classification, in combination with the structured prediction method conditional random fields. An improvement in overall accuracy, and sensitivity of every category under investigation is achieved.

  4. Congestive renal failure: the pathophysiology and treatment of renal venous hypertension.

    Science.gov (United States)

    Ross, Edward A

    2012-12-01

    Longstanding experimental evidence supports the role of renal venous hypertension in causing kidney dysfunction and "congestive renal failure." A focus has been heart failure, in which the cardiorenal syndrome may partly be due to high venous pressure, rather than traditional mechanisms involving low cardiac output. Analogous diseases are intra-abdominal hypertension and renal vein thrombosis. Proposed pathophysiologic mechanisms include reduced transglomerular pressure, elevated renal interstitial pressure, myogenic and neural reflexes, baroreceptor stimulation, activation of sympathetic nervous and renin angiotensin aldosterone systems, and enhanced proinflammatory pathways. Most clinical trials have addressed the underlying condition rather than venous hypertension per se. Interpreting the effects of therapeutic interventions on renal venous congestion are therefore problematic because of such confounders as changes in left ventricular function, cardiac output, and blood pressure. Nevertheless, there is preliminary evidence from small studies of intense medical therapy or extracorporeal ultrafiltration for heart failure that there can be changes to central venous pressure that correlate inversely with renal function, independently from the cardiac index. Larger more rigorous trials are needed to definitively establish under what circumstances conventional pharmacologic or ultrafiltration goals might best be directed toward central venous pressures rather than left ventricular or cardiac output parameters. Copyright © 2012 Elsevier Inc. All rights reserved.

  5. Atrial – Ventricular Septal Defect

    Directory of Open Access Journals (Sweden)

    T Panagiotopoulos

    2009-05-01

    Full Text Available Atrial and ventricular septal defect constitute the most common congenital heart disease.Aim: Τhe aim of the present retrospective study was to record data and factors that affect atrial and ventricular septal defect.Method and material: The sample study included patients of both sexes who were hospitalized with diagnosis atrial and ventricular septal defect in a Cardiac Surgery hospital of Athens. A specially constructed printed form was used for data collection, where were recorded the demographic and personal variables, the pathological, surgical, cardiology and obstetric history, the habits of adults, as well as the personal characteristics of mothers. Analysis of data was performed by descriptive statistical analysis.Results: The sample study consisted of 101 individuals with diagnosis atrial or ventricular Septal Defect, of which 40% were boys and 60% girls. The 70% of the sample study suffered from atrial Septal Defect and the 30% suffered from ventricular Septal Defect. Regarding age, 12% of the sample study was 0-1 years old, 35% was >1 years old, 8% was >12-18 years old and 45% over than 18 years old. Regarding educational status of the adult participants, 9% was of 0-6 years education, 22%>6 -12 years, 13%>12 years. 14% of the adult paticipants smoked, 4% consumed alcohol and 5% smoked in conjunction with alcohol. In terms of the obstetric history of the sample studied, 32% of the cases had normal birth, 4% had a twin birth and 1% had a triplet one. According to the variables related to mothers, the mean age of the mother was 30 years and 3 months, 10% were smokers at pregnancy and 3% used chemical substance and mainly hair color. Also, the results of the present study showed that individuals of 12-18 and >18 years old did not suffer from ventricular Septal Defect, whereas the infants 0-1 years old did not suffer from Atrial Septal Defect. The mean value of age at the admission in intensive care unit was 7 months (12% for the infants

  6. Hypertrophic Cardiomyopathy from A to Z: Genetics, Pathophysiology, Imaging, and Management.

    Science.gov (United States)

    Baxi, Ameya Jagdish; Restrepo, Carlos S; Vargas, Daniel; Marmol-Velez, Alejandro; Ocazionez, Daniel; Murillo, Horacio

    2016-01-01

    Hypertrophic cardiomyopathy (HCM) is a heterogeneous group of diseases related to sarcomere gene mutations exhibiting heterogeneous phenotypes with an autosomal dominant mendelian pattern of inheritance. The disorder is characterized by diverse phenotypic expressions and variable natural progression, which may range from dyspnea and/or syncope to sudden cardiac death. It is found across all racial groups and is associated with left ventricular hypertrophy in the absence of another systemic or cardiac disease. The management of HCM is based on a thorough understanding of the underlying morphology, pathophysiology, and clinical course. Imaging findings of HCM mirror the variable expressivity and penetrance heterogeneity, with the added advantage of diagnosis even in cases where a specific mutation may not yet be found. The diagnostic information obtained from imaging varies depending on the specific stage of HCM-phenotype manifestation, including the prehypertrophic, hypertrophic, and later stages of adverse remodeling into the burned-out phase of overt heart failure. However, subtle or obvious, these imaging findings become critical components in diagnosis, management, and follow-up of HCM patients. Although diagnosis of HCM traditionally relies on clinical assessment and transthoracic echocardiography, recent studies have demonstrated increased utility of multidetector computed tomography (CT) and particularly cardiac magnetic resonance (MR) imaging in diagnosis, phenotype differentiation, therapeutic planning, and prognostication. In this article, we provide an overview of the genetics, pathophysiology, and clinical manifestations of HCM, with the spectrum of imaging findings at MR imaging and CT and their contribution in diagnosis, risk stratification, and therapy.

  7. Predictive value of electrical restitution in hypokalemia-induced ventricular arrhythmogenicity

    DEFF Research Database (Denmark)

    Osadchii, Oleg E; Larsen, Anders Peter; Olesen, Soren Peter

    2009-01-01

    the predictive value of electrical restitution in hypokalemia-induced arrhythmogenicity. We recorded monophasic APs and measured effective refractory periods (ERP) at distinct ventricular epicardial and endocardial sites and monitored volume-conducted ECG at baseline and after hypokalemic perfusion (2.5 mM K......The ventricular action potential (AP) shortens exponentially upon a progressive reduction of the preceding diastolic interval. Steep electrical restitution slopes have been shown to promote wavebreaks, thus contributing to electrical instability. The present study was designed to assess......(+) for 30 min) in isolated guinea pig heart preparations. The restitution of AP duration measured at 90% repolarization (APD(90)) was assessed after premature extrastimulus application at variable coupling stimulation intervals, and ERP restitution was assessed by measuring refractoriness over a wide range...

  8. Intestinal CFTR expression alleviates meconium ileus in cystic fibrosis pigs.

    Science.gov (United States)

    Stoltz, David A; Rokhlina, Tatiana; Ernst, Sarah E; Pezzulo, Alejandro A; Ostedgaard, Lynda S; Karp, Philip H; Samuel, Melissa S; Reznikov, Leah R; Rector, Michael V; Gansemer, Nicholas D; Bouzek, Drake C; Abou Alaiwa, Mahmoud H; Hoegger, Mark J; Ludwig, Paula S; Taft, Peter J; Wallen, Tanner J; Wohlford-Lenane, Christine; McMenimen, James D; Chen, Jeng-Haur; Bogan, Katrina L; Adam, Ryan J; Hornick, Emma E; Nelson, George A; Hoffman, Eric A; Chang, Eugene H; Zabner, Joseph; McCray, Paul B; Prather, Randall S; Meyerholz, David K; Welsh, Michael J

    2013-06-01

    Cystic fibrosis (CF) pigs develop disease with features remarkably similar to those in people with CF, including exocrine pancreatic destruction, focal biliary cirrhosis, micro-gallbladder, vas deferens loss, airway disease, and meconium ileus. Whereas meconium ileus occurs in 15% of babies with CF, the penetrance is 100% in newborn CF pigs. We hypothesized that transgenic expression of porcine CF transmembrane conductance regulator (pCFTR) cDNA under control of the intestinal fatty acid-binding protein (iFABP) promoter would alleviate the meconium ileus. We produced 5 CFTR-/-;TgFABP>pCFTR lines. In 3 lines, intestinal expression of CFTR at least partially restored CFTR-mediated anion transport and improved the intestinal phenotype. In contrast, these pigs still had pancreatic destruction, liver disease, and reduced weight gain, and within weeks of birth, they developed sinus and lung disease, the severity of which varied over time. These data indicate that expressing CFTR in intestine without pancreatic or hepatic correction is sufficient to rescue meconium ileus. Comparing CFTR expression in different lines revealed that approximately 20% of wild-type CFTR mRNA largely prevented meconium ileus. This model may be of value for understanding CF pathophysiology and testing new preventions and therapies.

  9. PREDICTORS OF MORTALITY IN PATIENTS WITH SUSTAINED VENTRICULAR TACHYCARDIAS OR VENTRICULAR-FIBRILLATION AND DEPRESSED LEFT-VENTRICULAR FUNCTION - IMPORTANCE OF BETA-BLOCKADE

    NARCIS (Netherlands)

    SZABO, BM; CRIJNS, HJGM; WIESFELD, ACP; VANVELDHUISEN, DJ; HILLEGE, HL; LIE, KI

    1995-01-01

    To study prognostic factors in patients with sustained ventricular tachycardias (VT) or ventricular fibrillation (VF) complicated by left ventricular dysfunction, we evaluated the predictive value of demographic, clinical, and hemodynamic parameters for cardiac mortality and sudden cardiac death in

  10. 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.

  11. An overview of the Charcot foot pathophysiology.

    Science.gov (United States)

    Kaynak, Gökhan; Birsel, Olgar; Güven, Mehmet Fatih; Oğüt, Tahir

    2013-01-01

    Charcot arthropathy of the foot is a rare but devastating complication of diabetes that remains to be a challenging issue for the foot and ankle surgeons. Charcot foot fails to be an obvious diagnostic option that comes to mind, even in a pathognomonic clinical appearance. The rarity of the disorder, more common pathologies that mimic the condition, and the self-limiting prognosis deviate the clinician from the right diagnosis. The clinical challenges in the diagnosis of Charcot foot require in-depth investigations of its enigmatic nature to establish useful guidelines. Yet, this goal seems to be beyond reach, without a holistic view of the immense literature concerning the pathophysiology of the disorder. The primary objective of this article is to put together and review the recent advancements about the etiology and intrinsic mechanisms of diabetic Charcot foot.

  12. An overview of the Charcot foot pathophysiology

    Directory of Open Access Journals (Sweden)

    Gökhan Kaynak

    2013-08-01

    Full Text Available Charcot arthropathy of the foot is a rare but devastating complication of diabetes that remains to be a challenging issue for the foot and ankle surgeons. Charcot foot fails to be an obvious diagnostic option that comes to mind, even in a pathognomonic clinical appearance. The rarity of the disorder, more common pathologies that mimic the condition, and the self-limiting prognosis deviate the clinician from the right diagnosis. The clinical challenges in the diagnosis of Charcot foot require in-depth investigations of its enigmatic nature to establish useful guidelines. Yet, this goal seems to be beyond reach, without a holistic view of the immense literature concerning the pathophysiology of the disorder. The primary objective of this article is to put together and review the recent advancements about the etiology and intrinsic mechanisms of diabetic Charcot foot.

  13. The role of ADAMs in disease pathophysiology.

    LENUS (Irish Health Repository)

    Duffy, Michael J

    2012-02-01

    The ADAMs are a family of multidomain transmembrane and secreted proteins involved in both proteolysis and cell adhesion. Altered expression of specific ADAMs is implicated in the pathophysiology of several diseases including rheumatoid arthritis, Alzheimer\\'s disease, cardiac hypertrophy, asthma and cancer. Of these different diseases, it is in cancer where most research has been carried out. Multiple ADAMs, including ADAM-9, ADAM-10, ADAM-12, ADAM-15 and ADAM-17, have been shown to play a role in either cancer formation or progression. Consistent with these findings, increased expression of specific ADAMs in several cancer types was found to correlate with features of aggressive disease and poor prognosis. Currently, selective ADAM inhibitors against ADAM-10 and ADAM-17 are undergoing clinical trials for the treatment of cancer. Further work is required in order to establish a causative role for ADAMs in rheumatoid arthritis, Alzheimer\\'s disease, cardiac hypertrophy and asthma.

  14. Cell volume regulation: physiology and pathophysiology

    DEFF Research Database (Denmark)

    Lambert, I H; Hoffmann, E K; Pedersen, Stine Helene Falsig

    2008-01-01

    not only under physiological conditions, e.g. following accumulation of nutrients, during epithelial absorption/secretion processes, following hormonal/autocrine stimulation, and during induction of apoptosis, but also under pathophysiological conditions, e.g. hypoxia, ischaemia and hyponatremia....../hypernatremia. On the other hand, it has recently become clear that an increase or reduction in cell volume can also serve as a specific signal in the regulation of physiological processes such as transepithelial transport, cell migration, proliferation and death. Although the mechanisms by which cell volume perturbations...... are sensed are still far from clear, significant progress has been made with respect to the nature of the sensors, transducers and effectors that convert a change in cell volume into a physiological response. In the present review, we summarize recent major developments in the field, and emphasize...

  15. Autism: Pathophysiology and Promising Herbal Remedies.

    Science.gov (United States)

    Bahmani, Mahmoud; Sarrafchi, Amir; Shirzad, Hedayatollah; Rafieian-Kopaei, Mahmoud

    2016-01-01

    Autism is a comprehensive growth abnormality in which social skills, language, communication, and behavioral skills are developed with delay and as diversionary. The reasons for autism are unclear, but various theories of genetics, immunity, biological, and psychosocial factors have been proffered. In fact, autism is a complex disorder with distinct causes that usually co-occur. Although no medicine has been recognized to treat this disorder, pharmacological treatments can be effective in reducing its signs, such as self-mutilation, aggression, repetitive and stereotyped behaviors, inattention, hyperactivity, and sleeping disorders. Recently, complementary and alternative approaches have been considered to treat autism. Ginkgo biloba is one of the most effective plants with an old history of applications in neuropsychological disorders which recently is used for autism. The present review discusses the recent findings, pathophysiology, and etiology of autism and thereafter addresses the promising results of herbal remedies.

  16. Redox signaling in pathophysiology of hypertension.

    Science.gov (United States)

    Majzunova, Miroslava; Dovinova, Ima; Barancik, Miroslav; Chan, Julie Y H

    2013-09-18

    Reactive oxygen species (ROS) are products of normal cellular metabolism and derive from various sources in different cellular compartments. Oxidative stress resultant from imbalance between ROS generation and antioxidant defense mechanisms is important in pathogenesis of cardiovascular diseases, such as hypertension, heart failure, atherosclerosis, diabetes, and cardiac hypertrophy. In this review we focus on hypertension and address sources of cellular ROS generation, mechanisms involved in regulation of radical homeostasis, superoxide dismutase isoforms in pathophysiology of hypertension; as well as radical intracellular signaling and phosphorylation processes in proteins of the affected cardiovascular tissues. Finally, we discuss the transcriptional factors involved in redox-sensitive gene transcription and antioxidant response, as well as their roles in hypertension.

  17. Role of leukotrienes in asthma pathophysiology

    DEFF Research Database (Denmark)

    Bisgaard, H

    2000-01-01

    -line anti-inflammatory therapy for asthma management. However, in some patients, especially children, the high doses of corticosteroids that may be required to control features of hyperresponsiveness, including exercise-induced asthma, raise safety concerns. Thus, there is a need for complementary anti......Inflammation is an essential component of asthma pathophysiology. While beta(2)-agonists are often used for short-term relief of acute bronchospasm, anti-inflammatory agents are required for the long-term management of chronic inflammation in this disease. Corticosteroids have emerged as the first......-inflammatory, steroid-sparing agents in asthma therapy. Several inflammatory mediators have been targeted in an attempt to thwart this inflammatory process, but so far with little success. The cysteinyl leukotrienes (CysLT), LTC(4), LTD(4), and LTE(4), have been shown to be essential mediators in asthma, making them...

  18. Pathophysiology, Clinical, and Therapeutic Aspects of Narcolepsy

    Directory of Open Access Journals (Sweden)

    Pinar Guzel Ozdemir

    2014-09-01

    Full Text Available Narcolepsy is a lifelong sleep disorder characterized by excessive daytime sleepiness, cataplexy, hypnagogic hallucination, and sleep paralysis. The exact cause remains unknown, but there is significant evidence that hypocretin deficiency plays an integral role. There have been advances in the understanding of the pathogenesis of narcolepsy. It has a negative effect on the quality of life and can restrict the patients from certain careers and activities. Diagnosis relies on patient history and objective data gathered from polysomnography and multiple sleep latency testing. Treatment focuses on symptom relief through medication, education, and behavioral modification. Both classic pharmacological treatments as well as newer options have significant problems, especially because of side effects and abuse potential. Some novel modalities are being examined to expand options for treatment. In this review, the pathophysiological, clinical, and pharmacotherapeutic aspects of narcolepsy are discussed. [Psikiyatride Guncel Yaklasimlar - Current Approaches in Psychiatry 2014; 6(3.000: 271-283

  19. Eyelid aging: pathophysiology and clinical management

    Directory of Open Access Journals (Sweden)

    Renato Wendell Damasceno

    2015-10-01

    Full Text Available ABSTRACTLife expectancy is increasing in most countries. With increasing age, many individuals may develop involutional ophthalmic diseases, such as eyelid aging. Dermatochalasis, ptosis, ectropion, and entropion are common disorders in middle-aged and older adults. This review outlines the pathophysiology and clinical management of these involutional eyelid disorders. Recently, a decrease in elastic fibers with ultrastructural abnormalities and an overexpression of elastin-degrading enzymes have been demonstrated in involutional ectropion and entropion. This may be the consequence of local ischemia, inflammation, and/or chronic mechanical stress. Eyelid aging with progressive loss of tone and laxity may affect the ocular surface and adnexal tissues, resulting in different clinical symptoms and signs. Surgical management depends on the appropriate correction of the underlying anatomical defect.

  20. Task-specific dystonia: pathophysiology and management.

    Science.gov (United States)

    Sadnicka, Anna; Kassavetis, Panagiotis; Pareés, Isabel; Meppelink, Anne Marthe; Butler, Katherine; Edwards, Mark

    2016-09-01

    Task-specific dystonia is a form of isolated focal dystonia with the peculiarity of being displayed only during performance of a specific skilled motor task. This distinctive feature makes task-specific dystonia a particularly mysterious and fascinating neurological condition. In this review, we cover phenomenology and its increasingly broad-spectrum risk factors for the disease, critically review pathophysiological theories and evaluate current therapeutic options. We conclude by highlighting the unique features of task-specific dystonia within the wider concept of dystonia. We emphasise the central contribution of environmental risk factors, and propose a model by which these triggers may impact on the motor control of skilled movement. By viewing task-specific dystonia through this new lens which considers the disorder a modifiable disorder of motor control, we are optimistic that research will yield novel therapeutic avenues for this highly motivated group of patients.

  1. [Aerosinusitis: part 1: Fundamentals, pathophysiology and prophylaxis].

    Science.gov (United States)

    Weber, R; Kühnel, T; Graf, J; Hosemann, W

    2014-01-01

    The relevance of aerosinusitis stems from the high number of flight passengers and the impaired fitness for work of the flight personnel. The frontal sinus is more frequently affected than the maxillary sinus and the condition generally occurs during descent. Sinonasal diseases and anatomic variations leading to obstruction of paranasal sinus ventilation favor the development of aerosinusitis. This Continuing Medical Education (CME) article is based on selective literature searches of the PubMed database (search terms: "aerosinusitis", "barosinusitis", "barotrauma" AND "sinus", "barotrauma" AND "sinusitis", "sinusitis" AND "flying" OR "aviator"). Additionally, currently available monographs and further articles that could be identified based on the publication reviews were also included. Part 1 presents the pathophysiology, symptoms, risk factors, epidemiology and prophylaxis of aerosinusitis. In part 2, diagnosis, conservative and surgical treatment will be discussed.

  2. Treatment of cellulite: Part I. Pathophysiology.

    Science.gov (United States)

    Khan, Misbah H; Victor, Frank; Rao, Babar; Sadick, Neil S

    2010-03-01

    Cellulite is a topographic skin change that is nearly ubiquitous in postpubertal women. Treatment remains elusive. The various treatments currently available are only partially or temporarily effective. Newer therapeutic modalities continue to evolve without much understanding of the complex nature of cellulite. The successful treatment of cellulite will ultimately depend upon our understanding of the pathophysiology of cellulite adipose tissue. Part I of this two-part series on cellulite reviews how the concept and perception of cellulite has evolved over time and its proposed etiologies. The article also focuses on the physiology of human adipose tissue, particularly regarding cellulite. Copyright 2009 American Academy of Dermatology, Inc. Published by Mosby, Inc. All rights reserved.

  3. [Pathophysiology and treatment of orofacial pain.

    Science.gov (United States)

    Shinoda, Masamichi; Noma, Noboru

    2017-01-01

    "Pain" is one of body defense mechanisms and crucial for the life support. However, orofacial pain such as myofascial pain syndrome, burning mouth syndrome and trigeminal neuralgia plays no part in body defense mechanisms and requires therapeutic intervention. Recent studies have indicated that plastic changes in the activities of trigeminal neurons, satellite glial cells in trigeminal ganglion, secondary neurons, microglia and astrocytes in trigeminal spinal subnucleus following orofacial inflammation and trigeminal nerve injury are responsible for orofacial pain mechanisms. Clinically, it is well known that the etiologic differential diagnosis which consists of careful history-taking and physical examination is essential for therapeutic decision in patients with orofacial pain. This report outlines the current knowledge on the pathophysiology, diagnosis, treatment of orofacial pain.

  4. Assessment of contractility in intact ventricular cardiomyocytes using the dimensionless 'Frank-Starling Gain' index.

    Science.gov (United States)

    Bollensdorff, Christian; Lookin, Oleg; Kohl, Peter

    2011-07-01

    This paper briefly recapitulates the Frank-Starling law of the heart, reviews approaches to establishing diastolic and systolic force-length behaviour in intact isolated cardiomyocytes, and introduces a dimensionless index called 'Frank-Starling Gain', calculated as the ratio of slopes of end-systolic and end-diastolic force-length relations. The benefits and limitations of this index are illustrated on the example of regional differences in Guinea pig intact ventricular cardiomyocyte mechanics. Potential applicability of the Frank-Starling Gain for the comparison of cell contractility changes upon stretch will be discussed in the context of intra- and inter-individual variability of cardiomyocyte properties.

  5. New insights into pathophysiology of vestibular migraine

    Directory of Open Access Journals (Sweden)

    Juan Manuel Espinosa-Sanchez

    2015-02-01

    Full Text Available Vestibular migraine (VM is a common disorder in which genetic, epigenetic and environmental factors probably contribute to its development. The pathophysiology of VM is unknown; nevertheless in the last few years, several studies are contributing to understand the neurophysiological pathways involved in VM. The current hypotheses are mostly based on the knowledge of migraine itself. The evidence of trigeminal innervation of the labyrinth vessels and the localization of vasoactive neuropeptides in the perivascular afferent terminals of these trigeminal fibers support the involvement of the trigemino-vascular system. The neurogenic inflammation triggered by activation of the trigeminal-vestibulocochlear reflex, with the subsequent inner ear plasma protein extravasation and the release of inflammatory mediators, can contribute to a sustained activation and sensitization of the trigeminal primary afferent neurons explaining VM symptoms. The reciprocal connections between brainstem vestibular nuclei and the structures that modulate trigeminal nociceptive inputs (rostral ventromedial medulla, ventrolateral periaqueductal grey, locus coeruleus and nucleus raphe magnus are critical to understand the pathophysiology of VM. Although cortical spreading depression can affect cortical areas involved in processing vestibular information, functional neuroimaging techniques suggest a dysmodulation in the multimodal sensory integration and processing of vestibular and nociceptive information, resulting from a vestibulo-thalamo-cortical dysfunction, as the pathogenic mechanism underlying VM. The elevated prevalence of VM suggests that multiple functional variants may confer a genetic susceptibility leading to a dysregulation of excitatory-inhibitory balance in brain structures involved in the processing of sensory information, vestibular inputs and pain. The interactions among several functional and structural neural networks could explain the pathogenic

  6. Erythrodermic psoriasis: pathophysiology and current treatment perspectives

    Directory of Open Access Journals (Sweden)

    Singh RK

    2016-07-01

    Full Text Available Rasnik K Singh,1 Kristina M Lee,2 Derya Ucmak,2 Merrick Brodsky,3 Zaza Atanelov,4 Benjamin Farahnik,5 Michael Abrouk,3 Mio Nakamura,2 Tian Hao Zhu,6 Wilson Liao2 1Department of Medicine, University of California – Los Angeles, David Geffen School of Medicine, Los Angeles, 2Department of Dermatology, University of California – San Francisco, San Francisco, 3Department of Medicine, University of California – Irvine, School of Medicine, Irvine, CA, 4Department of Medicine, New York Medical College, Valhalla, NY, 5Department of Medicine, University of Vermont College of Medicine, Burlington, VT, 6Department of Medicine, University of Southern California Keck School of Medicine, Los Angeles, CA, USA Abstract: Erythrodermic psoriasis (EP is a rare and severe variant of psoriasis vulgaris, with an estimated prevalence of 1%–2.25% among psoriatic patients. The condition presents with distinct histopathologic and clinical findings, which include a generalized inflammatory erythema involving at least 75% of the body surface area. The pathogenesis of EP is not well understood; however, several studies suggest that the disease is associated with a predominantly T helper 2 (Th2 phenotype. Given the morbidity and potential mortality associated with the condition, there is a need for a better understanding of its pathophysiology. The management of EP begins with a comprehensive assessment of the patient’s presentation and often requires multidisciplinary supportive measures. In 2010, the medical board of the US National Psoriasis Foundation published consensus guidelines advocating the use of cyclosporine or infliximab as first-line therapy in unstable cases, with acitretin and methotrexate reserved for more stable cases. Since the time of that publication, additional information regarding the efficacy of newer agents has emerged. We review the latest data with regard to the treatment of EP, which includes biologic therapies such as ustekinumab and

  7. Circadian molecular clock in lung pathophysiology.

    Science.gov (United States)

    Sundar, Isaac K; Yao, Hongwei; Sellix, Michael T; Rahman, Irfan

    2015-11-15

    Disrupted daily or circadian rhythms of lung function and inflammatory responses are common features of chronic airway diseases. At the molecular level these circadian rhythms depend on the activity of an autoregulatory feedback loop oscillator of clock gene transcription factors, including the BMAL1:CLOCK activator complex and the repressors PERIOD and CRYPTOCHROME. The key nuclear receptors and transcription factors REV-ERBα and RORα regulate Bmal1 expression and provide stability to the oscillator. Circadian clock dysfunction is implicated in both immune and inflammatory responses to environmental, inflammatory, and infectious agents. Molecular clock function is altered by exposomes, tobacco smoke, lipopolysaccharide, hyperoxia, allergens, bleomycin, as well as bacterial and viral infections. The deacetylase Sirtuin 1 (SIRT1) regulates the timing of the clock through acetylation of BMAL1 and PER2 and controls the clock-dependent functions, which can also be affected by environmental stressors. Environmental agents and redox modulation may alter the levels of REV-ERBα and RORα in lung tissue in association with a heightened DNA damage response, cellular senescence, and inflammation. A reciprocal relationship exists between the molecular clock and immune/inflammatory responses in the lungs. Molecular clock function in lung cells may be used as a biomarker of disease severity and exacerbations or for assessing the efficacy of chronotherapy for disease management. Here, we provide a comprehensive overview of clock-controlled cellular and molecular functions in the lungs and highlight the repercussions of clock disruption on the pathophysiology of chronic airway diseases and their exacerbations. Furthermore, we highlight the potential for the molecular clock as a novel chronopharmacological target for the management of lung pathophysiology.

  8. New Insights into Pathophysiology of Vestibular Migraine

    Science.gov (United States)

    Espinosa-Sanchez, Juan M.; Lopez-Escamez, Jose A.

    2015-01-01

    Vestibular migraine (VM) is a common disorder in which genetic, epigenetic, and environmental factors probably contribute to its development. The pathophysiology of VM is unknown; nevertheless in the last few years, several studies are contributing to understand the neurophysiological pathways involved in VM. The current hypotheses are mostly based on the knowledge of migraine itself. The evidence of trigeminal innervation of the labyrinth vessels and the localization of vasoactive neuropeptides in the perivascular afferent terminals of these trigeminal fibers support the involvement of the trigemino-vascular system. The neurogenic inflammation triggered by activation of the trigeminal-vestibulocochlear reflex, with the subsequent inner ear plasma protein extravasation and the release of inflammatory mediators, can contribute to a sustained activation and sensitization of the trigeminal primary afferent neurons explaining VM symptoms. The reciprocal connections between brainstem vestibular nuclei and the structures that modulate trigeminal nociceptive inputs (rostral ventromedial medulla, ventrolateral periaqueductal gray, locus coeruleus, and nucleus raphe magnus) are critical to understand the pathophysiology of VM. Although cortical spreading depression can affect cortical areas involved in processing vestibular information, functional neuroimaging techniques suggest a dysmodulation in the multimodal sensory integration and processing of vestibular and nociceptive information, resulting from a vestibulo-thalamo-cortical dysfunction, as the pathogenic mechanism underlying VM. The elevated prevalence of VM suggests that multiple functional variants may confer a genetic susceptibility leading to a dysregulation of excitatory–inhibitory balance in brain structures involved in the processing of sensory information, vestibular inputs, and pain. The interactions among several functional and structural neural networks could explain the pathogenic mechanisms of VM

  9. Outcome in Heart Failure with Preserved Ejection Fraction: The Role of Myocardial Structure and Right Ventricular Performance.

    Directory of Open Access Journals (Sweden)

    Georg Goliasch

    Full Text Available Heart failure with preserved ejection fraction (HFpEF is recognized as a major cause of cardiovascular morbidity and mortality. Thus, a profound understanding of the pathophysiologic changes in HFpEF is needed to identify risk factors and potential treatment targets in this specific patient population. Therefore, we aimed to comprehensively assess the impact of left- and right-ventricular function and hemodynamics on long-term mortality and morbidity in order to improve risk prediction in patients with HFpEF.We prospectively included 142 consecutive patients with HFpEF into our observational, non-interventional registry. Echocardiography, cardiac magnetic resonance imaging and invasive hemodynamic assessments including myocardial biopsy were performed at baseline. We detected significant correlations between left ventricular extracellular matrix and left ventricular end-diastolic diameter (r = -0.64;p = 0.03 and stroke volume (r = -0.53;p = 0.04. Hospitalization for heart failure and/or cardiac death was observed over a median follow up of 10 months. The strongest risk factors were reduced right ventricular function (adj. HR 6.62;95%CI 3.12- 14.02;p<0.001, systolic pulmonary arterial pressure (adj. HR per 1-SD 1.55;95%CI 1.15- 2.09;p = 0.004 and the pulmonary artery wedge pressure (adj. HR per 1-SD 1.51;95%CI 1.09-2.08; p = 0.012. The area under the ROC curve for right ventricular function was 0.63, for systolic pulmonary arterial pressure 0.75, and for pulmonary artery wedge pressure 0.68.The current study emphasizes the importance of right ventricular function and pulmonary pressures on outcome in patients with HFpEF providing pathophysiological insights into the hemodynamic changes in HFpEF.

  10. Heat stress in growing pigs

    NARCIS (Netherlands)

    Huynh Thi Thanh Thuy,

    2005-01-01

    Compared to other species of farm animals, pigs are more sensitive to high environmental temperatures, because they cannot sweat and do not pant so well. Furthermore, fast-growing lean pigs generate more heat than their congeners living in the wild. This, in combination with confined housing, makes

  11. Ventricular hypertrophy--physiological mechanisms.

    Science.gov (United States)

    Vaughan Williams, E M

    1986-01-01

    Adult cardiac myocytes are incapable of mitosis. Dead cells are replaced by connective tissue so that after myocardial infarction (MI), function can only be restored by compensatory hypertrophy of the surviving myocardium. In physiological hypertrophy in response to exercise, high altitude, or mild hypertension, additional myoplasm expands cell diameter in an orderly fashion; Z-lines are in register and the normal ratio of volume densities of contractile elements, mitochondria, and capillaries is conserved. In hypertrophy induced by aortic or pulmonary artery banding or by experimental or congenital hypertension, the borderline between physiological and pathological hypertrophy may be crossed, causing disorganization of fibers and an unfavourable contractile element to capillary ratio. There was, therefore, a need for a graded model of hypertrophy, which involves simulating an altitude of 6,000 m at sea level by supplying rabbits with appropriate nitrogen/oxygen mixtures. In this environment, 50% right ventricular hypertrophy can be achieved without alteration of left ventricular weight or hematocrit. Longer exposures produced 100% right ventricular hypertrophy, with only moderate increases in hematocrit and left ventricular weight. It is well known that adrenergic stimulation causes cardiac hypertrophy, and it has been suggested that release of a trophic factor from sympathetic nerves, either noradrenaline or a protein, might be a necessary stimulus for growth. If so, long-term treatment of post-MI patients with beta-adrenergic blocking agents could inhibit a desirable compensatory hypertrophy of the surviving myocardium. In the above model it has been found, however, that neither beta-blockade nor chemical sympathectomy with guanethidine or 6-hydroxydopamine had any effect on the hypertrophy, nor did treatment with verapamil or nifedipine.(ABSTRACT TRUNCATED AT 250 WORDS)

  12. Effects of biological sex on the pathophysiology of the heart

    National Research Council Canada - National Science Library

    Fazal, Loubina; Azibani, Feriel; Vodovar, Nicolas; Cohen Solal, Alain; Delcayre, Claude; Samuel, Jane‐Lise

    2014-01-01

    .... While the effects of biological sex on cardiovascular pathophysiology have long been known, the sex-specific mechanisms mediating these processes have been further elucidated over recent years...

  13. Left ventricular ejection time, not heart rate, is an independent correlate of aortic pulse wave velocity.

    Science.gov (United States)

    Salvi, Paolo; Palombo, Carlo; Salvi, Giovanni Matteo; Labat, Carlos; Parati, Gianfranco; Benetos, Athanase

    2013-12-01

    Several studies showed a positive association between heart rate and pulse wave velocity, a sensitive marker of arterial stiffness. However, no study involving a large population has specifically addressed the dependence of pulse wave velocity on different components of the cardiac cycle. The aim of this study was to explore in subjects of different age the link between pulse wave velocity with heart period (the reciprocal of heart rate) and the temporal components of the cardiac cycle such as left ventricular ejection time and diastolic time. Carotid-femoral pulse wave velocity was assessed in 3,020 untreated subjects (1,107 men). Heart period, left ventricular ejection time, diastolic time, and early-systolic dP/dt were determined by carotid pulse wave analysis with high-fidelity applanation tonometry. An inverse association was found between pulse wave velocity and left ventricular ejection time at all ages (pulse wave velocity and heart period was also found, with the exception of the youngest subjects (P = 0.20). A significant positive correlation was also found between pulse wave velocity and dP/dt (P pulse wave velocity at all ages, whereas the contribution of heart period no longer became significant. Our data demonstrate that pulse wave velocity is more closely related to left ventricular systolic function than to heart period. This may have methodological and pathophysiological implications.

  14. Left Ventricular Tonic Contraction as a Novel Biomarker of Cardiomyopathy in Duchenne Muscular Dystrophy.

    Science.gov (United States)

    Su, Jennifer A; Ramos-Platt, Leigh; Menteer, JonDavid

    2016-04-01

    Dilated cardiomyopathy (DCM) inevitably afflicts patients with Duchenne muscular dystrophy (DMD) as a consequence of cell death induced by unguarded calcium influx into cardiomyocytes. This mechanism may also inhibit muscle relaxation in early stages of cardiomyopathy. ACE inhibition (ACEi) is known to delay the onset and slow the progression of DCM in DMD. The objective of this study is to use echocardiography to assess for preclinical cardiac changes consistent with intracellular calcium dysregulation before the onset of overt ventricular dysfunction, and to evaluate how prophylactic ACEi may alter these pre-cardiomyopathic changes in the pediatric DMD population. We examined 263 echocardiograms from 70 pediatric patients with DMD. We defined abnormal tonic contraction (TC) as left ventricular internal dimension in diastole (LVIDd) Z-score < -1.5. In our cohort, we found that TC is detectable as early as 8 years of age, and most commonly affects patients between 11 and 15 years. This effect was independent of LV mass and systolic function. Prophylactic ACEi decreased the incidence of TC (p = 0.007) and preserved cardiac function (p < 0.0001). Left ventricular TC often precedes DCM in DMD, most commonly affecting the 11- to 15-year-old age range. TC is not related to ventricular hypertrophy, but rather may be a clinical correlate of the "calcium hypothesis" of DMD pathophysiology. LV TC is thus a promising biomarker for early detection of cardiomyopathy in DMD. ACEi prophylaxis suppresses LV TC and delays the development of DCM in DMD.

  15. Technology And Pregnant Pigs

    Science.gov (United States)

    1978-01-01

    One of the interesting things about aerospace spinoff is the way it keeps cropping up in uncommon applications unimaginably remote from the original technology. For example, the pig pregnancy detector. The pig pregnancy detector? City folk may be surprised to learn that there is such a thing-and wonder why. The why is because it is a sow's job to produce piglets and farmers can't afford to keep those who don't; it costs about a half-dollar a day in feed, labor and facilities, and even in small herds that's intolerable. So the barren sow must go. Until recently, the best method of determining pig pregnancy was "eyeballing," daily visual examination over a period of time. The problem with eyeballing is that pregnancy is not evident until well advanced; when there is no pregnancy, the farmer learns too late that he has been feeding a sow that won't give him a litter. Advancing technology provided an answer: the quick, easy-to-use, accurate automatic detector for early evaluation of pregnancy status. Among the most popular of these devices are Scanopreg and Scanoprobe, to whose development NASA technology contributed. Scanopreg is an ultrasonic system which detects pregnancy about 30 days after breeding, long before eyeballing can provide an answer. The companion Scanoprobe is a dual-function unit which not only determines pregnancy but also gives farmers an analysis of a hog's meat-fat ratio, an important factor in breeding. Only a short time on the market, Scanopreg and Scanoprobe have already found wide acceptance among meat producers because they rapidly repay their cost.

  16. Premature ventricular contractions associated with isotretinoin use.

    Science.gov (United States)

    Alan, Sevil; Ünal, Betül; Yildirim, Aytül

    2016-01-01

    Isotretinoin has been considered a unique drug for acne treatment. However, it is associated with numerous adverse effects. Isotretinoin can trigger premature ventricular contractions. This report describes a 33-year-old-woman who presented with palpitations for 1 week while undergoing 1-month isotretinoin treatment for mild-moderate facial acne. An electrocardiogram and Holter monitoring showed premature ventricular contractions during isotretinoin (Roaccutane, Roche) treatment. Isotretinoin-related premature ventricular contractions were strongly suggested in this case due to the existence of documented premature ventricular contractions on electrocardiograms and the disappearance of these premature ventricular contractions two weeks after termination of the treatment To the authors' knowledge, there has been 1 reported case of premature ventricular contractions linked to isotretinoin use; this report describes a second such case.

  17. Premature ventricular contractions associated with isotretinoin use*

    Science.gov (United States)

    Alan, Sevil; Ünal, Betül; Yildirim, Aytül

    2016-01-01

    Isotretinoin has been considered a unique drug for acne treatment. However, it is associated with numerous adverse effects. Isotretinoin can trigger premature ventricular contractions. This report describes a 33-year-old-woman who presented with palpitations for 1 week while undergoing 1-month isotretinoin treatment for mild-moderate facial acne. An electrocardiogram and Holter monitoring showed premature ventricular contractions during isotretinoin (Roaccutane, Roche) treatment. Isotretinoin-related premature ventricular contractions were strongly suggested in this case due to the existence of documented premature ventricular contractions on electrocardiograms and the disappearance of these premature ventricular contractions two weeks after termination of the treatment To the authors' knowledge, there has been 1 reported case of premature ventricular contractions linked to isotretinoin use; this report describes a second such case. PMID:28099609

  18. Modelling the distribution of pig production and diseases in Thailand

    OpenAIRE

    Thanapongtharm, Weerapong

    2015-01-01

    This thesis, entitled “Modelling the distribution of pig production and diseases in Thailand”, presents many aspects of pig production in Thailand including the characteristics of pig farming system, distribution of pig population and pig farms, spatio-temporal distribution and risk of most important diseases in pig at present, and the suitability area for pig farming. Spatial distribution and characteristics of pig farming in Thailand were studied using time-series pig population data to des...

  19. Behavior of immunocastrated pigs

    Directory of Open Access Journals (Sweden)

    Rita de Kássia Silva dos Santos

    Full Text Available ABSTRACT The objective of this study was to evaluate the behavior of immunocastrated male pigs compared with females and castrated males during the period before and after full immunization. A total of 30 animals were divided into three treatments, with ten animals in each (females, barrows, and immunocastrated males. The experiment was divided into three periods: 70 to 80 days of age (period 1, 81 to 110 days of age (period 2, and 111 to 140 days of age (period 3. The behavior of animals during these stages was evaluated. Immunocastrated males showed a higher rate of aggressive and sexual behavior during period 2, which decreased after the second vaccine dose. Both barrows and immunocastrated males presented high locomotion in period 1, reducing the frequency of this activity in period 3. All analyzed animals had a higher level of activities such as drinking, playing, and sexual behavior in period 1 than in the other periods, decreasing during the experiment. The remaining behavioral responses did not differ between the studied categories. Immunocastrated males had higher proportions of undesirable behaviors (aggressive and sexual related to the surgically castrated males and females, and these were reduced after the second vaccine dose. Immunocastration is effective in the reduction of behaviors such as agonistic and sexual at the same levels observed in females and surgically castrated males. However, immunocastrated pigs are more subject to these undesirable behaviors before full immunization.

  20. Reconstituição da valva pulmonar e via de saída do ventrículo direito, com prótese bivalvular e prótese tubular valvada de tronco pulmonar de porco: estudo experimental e aplicação clínica Pulmonary valve and right ventricular oulet tract reconstruction with biovalvular prostheses and valved tubular prostheses of the pig pulmonary artery: experimental study and clinical application

    Directory of Open Access Journals (Sweden)

    Miguel A Maluf

    1993-03-01

    aplicação clínica da prótese bivalvular foi realizada em 3 pacientes portadores de t. de Fallot associada a hipoplasía do anel pulmonar (2 casos e agenesia da valva pulmonar (1 caso, com idades de 16, 2 e 7 anos. Após evolução de 3 a 10 meses, os gradientes variaram entre 10 mmHg e 20 mmHg e discreta insuficiência pulmonar valvar ao estudo ecodopplercardiográfico. A prótese tubular valvar foi implantada em 2 pacientes portadores de atresia pulmonar associada a comunicação interventricular (CIV e outro a transposição corrigida das grandes artérias (TCGA associada a GIV e estenose subpulmonar, com idades de 10 e 6 anos, respectivamente. Após evolução de 5 a 12 meses, foram detectados suficiência da valva pulmonar, gradientes entre 15 mmHg e 18 mmHg, sem sinais de calcificação. Apesar de se considerar aceitáveis os resultados desta experiência, a ampliação das indicações deverá ser feita com cautela, até o melhor conhecimento da resistência da prótese a calcificação, infecção, obstrução e rotura.Obstruction of the right ventricle outlet tract (RVOT has been the object of arguments regarding its surgical correction, while there are different criteria for reconstruction. Thus two kinds of prostheses were developed from the pig pulmonary trunk (PT. 1 One with two valves of the pulmonary valve (PV, named bivalvular graft, and could be used for correction of Fallot with pulmonary ring hypoplasia. 2 The other, with a tubular form, containing the pig PV itself and named valved conduit, could be used in RVOT reconstruction for patients with pulmonary atresia (PA. These prostheses were tested in an experimental model: implant of the bivalvular graft was performed in 16 sheep with the aid of extracorporeal circulation (ECC. The surgical technique consisted of resection of the two valves of the PV and of the anterior wall of the infundibulum; this condition was similar to Fallot correction. Implant of the valvular conduit was carried out in 12

  1. Different Pathophysiological Phenotypes among Newly Diagnosed Type 2 Diabetes Patients

    DEFF Research Database (Denmark)

    Stidsen, Jacob

    2013-01-01

    Type 2 diabetes (T2D) can be considered a syndrome with several different pathophysiological mechanisms leading to hyperglycemia. Nonetheless, T2D is treated according to algorithms as if it was one disease entity. Methods: We investigated the prevalence of different pathophysiological phenotypes...

  2. Somatosensory dysfunctin in fibromyaligia : Implications for pathophysiological mechanisms

    OpenAIRE

    1996-01-01

    SOMATOSENSORY DYSFUNCTION IN FIBROMYALGIA. IMPLICATIONS FOR PATHOPHYSIOLOGICAL MECHANISMS. Eva KosekDissertation from the Department of Rehabilitation Medicine, Karolinska Institure/Hospital, Stoclcholm, Sweden Fibromyalgia is a chronic pain syndrome characterized by generalized pain, tenderness,disturbed sleep and pronounced fatigue. The pathophysiology is unknown ...

  3. Contemporary management of acute right ventricular failure: a statement from the Heart Failure Association and the Working Group on Pulmonary Circulation and Right Ventricular Function of the European Society of Cardiology.

    Science.gov (United States)

    Harjola, Veli-Pekka; Mebazaa, Alexandre; Čelutkienė, Jelena; Bettex, Dominique; Bueno, Hector; Chioncel, Ovidiu; Crespo-Leiro, Maria G; Falk, Volkmar; Filippatos, Gerasimos; Gibbs, Simon; Leite-Moreira, Adelino; Lassus, Johan; Masip, Josep; Mueller, Christian; Mullens, Wilfried; Naeije, Robert; Nordegraaf, Anton Vonk; Parissis, John; Riley, Jillian P; Ristic, Arsen; Rosano, Giuseppe; Rudiger, Alain; Ruschitzka, Frank; Seferovic, Petar; Sztrymf, Benjamin; Vieillard-Baron, Antoine; Yilmaz, Mehmet Birhan; Konstantinides, Stavros

    2016-03-01

    Acute right ventricular (RV) failure is a complex clinical syndrome that results from many causes. Research efforts have disproportionately focused on the failing left ventricle, but recently the need has been recognized to achieve a more comprehensive understanding of RV anatomy, physiology, and pathophysiology, and of management approaches. Right ventricular mechanics and function are altered in the setting of either pressure overload or volume overload. Failure may also result from a primary reduction of myocardial contractility owing to ischaemia, cardiomyopathy, or arrhythmia. Dysfunction leads to impaired RV filling and increased right atrial pressures. As dysfunction progresses to overt RV failure, the RV chamber becomes more spherical and tricuspid regurgitation is aggravated, a cascade leading to increasing venous congestion. Ventricular interdependence results in impaired left ventricular filling, a decrease in left ventricular stroke volume, and ultimately low cardiac output and cardiogenic shock. Identification and treatment of the underlying cause of RV failure, such as acute pulmonary embolism, acute respiratory distress syndrome, acute decompensation of chronic pulmonary hypertension, RV infarction, or arrhythmia, is the primary management strategy. Judicious fluid management, use of inotropes and vasopressors, assist devices, and a strategy focusing on RV protection for mechanical ventilation if required all play a role in the clinical care of these patients. Future research should aim to address the remaining areas of uncertainty which result from the complexity of RV haemodynamics and lack of conclusive evidence regarding RV-specific treatment approaches.

  4. [Vestibular neuronitis: pathophysiology, diagnosis and treatment].

    Science.gov (United States)

    Zaper, Dinka; Adamec, Ivan; Gabelić, Tereza; Krbot, Magdalena; Isgum, Velimir; Hajnsek, Sanja; Habek, Mario

    2012-01-01

    Vestibular neuritis (VN) is one of the most common causes of peripheral vertigo. Caloric testing has been the traditional gold standard for detecting a peripheral vestibular deficit, but some recently developed bedside tests (head thrust, head heave, head shake and vibration test) were evaluated as a good alternative with similar sensitivity and specificity. These tests have shown both diagnostic value in the short term and prognostic value in the long term, and have availability and ease of use as an advantage. As an addition to clinical examination, vestibular evoked myogenic potentials can differentiate between involvement of superior and inferior branch of the vestibular nerve, but also between peripheral and central lesions. Although glucocorticoids are currently widely used in the treatment of VN, there is a lack of evidence for the validity of their administration. There are a number of high quality clinical trials that suggest vestibular rehabilitation exercises, which are based on the mechanisms of vestibular compensation, in the managment of VN. This review will focus on the latest developments in the pathophysiology, diagnosis and treatment of patients with VN.

  5. The Charcot foot: pathophysiology, diagnosis and classification.

    Science.gov (United States)

    Trieb, K

    2016-09-01

    Neuropathic changes in the foot are common with a prevalence of approximately 1%. The diagnosis of neuropathic arthropathy is often delayed in diabetic patients with harmful consequences including amputation. The appropriate diagnosis and treatment can avoid an extensive programme of treatment with significant morbidity for the patient, high costs and delayed surgery. The pathogenesis of a Charcot foot involves repetitive micro-trauma in a foot with impaired sensation and neurovascular changes caused by pathological innervation of the blood vessels. In most cases, changes are due to a combination of both pathophysiological factors. The Charcot foot is triggered by a combination of mechanical, vascular and biological factors which can lead to late diagnosis and incorrect treatment and eventually to destruction of the foot. This review aims to raise awareness of the diagnosis of the Charcot foot (diabetic neuropathic osteoarthropathy and the differential diagnosis, erysipelas, peripheral arterial occlusive disease) and describe the ways in which the diagnosis may be made. The clinical diagnostic pathways based on different classifications are presented. Cite this article: Bone Joint J 2016;98-B:1155-9.

  6. Pathophysiology of constipation in the older adult

    Institute of Scientific and Technical Information of China (English)

    G Lindsay McCrea; Christine Miaskowski; Nancy A Stotts; Liz Macera; Madhulika G Varma

    2008-01-01

    This review provides information on the definition of constipation,normal continence and defecation and a description of the pathophysiologic mechanisms of constipation.In addition,changes in the anatomy and physiology of the lower gastrointestinal tract associated with aging that may contribute to constipation are described.MEDLINE (1966-2007) and CINAHL (1980-2007) were searched.The following MeSH terms were used:constipation/etiology OR constipation/physiology OR constipation/physiopathology) AND (age factors OR aged OR older OR 80 and over OR middle age).Constipation is not well defined in the literature.While self-reported constipation increases with age,findings from a limited number of clinical studies that utilized objective measures do not support this association.Dysmotility and pelvic floor dysfunction are important mechanisms associated with constipation.Changes in GI function associated with aging appear to be relatively subtle based on a limited amount of conflicting data.Additional research is warranted on the effects of aging on GI function,as well as on the timing of these changes.

  7. Perimenstrual asthma: from pathophysiology to treatment strategies.

    Science.gov (United States)

    Graziottin, Alessandra; Serafini, Audrey

    2016-01-01

    The prevalence of asthma is about 9,7 % in women and 5,5 % in men. Asthma can deteriorate during the perimenstrual period, a phenomenon known as perimenstrual asthma (PMA), which represents a unique, highly symptomatic asthma phenotype. It is distinguished from traditional allergic asthma by aspirin sensitivity, less atopy, and lower lung capacity. PMA incidence is reported to vary between 19 and 40 % of asthmatic women. The presence of PMA has been related to increases in asthma-related emergency department visits, hospitalizations and emergency treatment including intubations. It is hypothesized that hormonal status may influence asthma in women, focusing on the role of sex hormones, and specifically on the impact of estrogens' fluctuations at ovulation and before periods. This paper will focus on the pathophysiology of hormone triggered cycle related inflammatory/allergic events and their relation with asthma. We reviewed the scientific literature on Pubmed database for studies on PMA. Key word were PMA, mastcells, estrogens, inflammation, oral contraception, hormonal replacement therapy (HRT), and hormone free interval (HFI). Special attention will be devoted to the possibility of reducing the perimenstrual worsening of asthma and associated symptoms by reducing estrogens fluctuations, with appropriate hormonal contraception and reduced HFI. This novel therapeutical approach will be finally discussed.

  8. Pathophysiology and epidemiology of peripartum cardiomyopathy.

    Science.gov (United States)

    Hilfiker-Kleiner, Denise; Sliwa, Karen

    2014-06-01

    Cardiovascular diseases are a major cause of complications in pregnancy worldwide, and the number of patients who develop cardiac problems during pregnancy is increasing. Peripartum cardiomyopathy (PPCM) is a potentially life-threatening heart disease that emerges towards the end of pregnancy or in the first months postpartum, in previously healthy women. Symptoms and signs of PPCM are similar to those in patients with idiopathic dilated cardiomyopathy. The incidence varies geographically, most likely because of socioeconomic and genetic factors. The syndrome is associated with a high morbidity and mortality, and diagnosis is often delayed. Various mechanisms have been investigated, including the hypothesis that unbalanced peripartum or postpartum oxidative stress triggers the proteolytic cleavage of the nursing hormone prolactin into a potent antiangiogenic, proapoptotic, and proinflammatory 16 kDa fragment. This theory provides the basis for the discovery of disease-specific biomarkers and promising novel therapeutic targets. In this Review, we describe the latest understanding of the epidemiology, pathophysiology, and novel treatment strategies for patients with PPCM.

  9. Adipose tissue remodeling in pathophysiology of obesity.

    Science.gov (United States)

    Lee, Mi-Jeong; Wu, Yuanyuan; Fried, Susan K

    2010-07-01

    Recent studies demonstrate that adipose tissue undergoes a continuous process of remodeling that is pathologically accelerated in the obese state. Contrary to earlier dogma, adipocytes die and are replaced by newly differentiated ones. This review will summarize recent advances of our knowledge of the mechanisms that regulate adipose tissue remodeling and highlight the influences of obesity, depot, and sex, as well as the relevance of rodent models to humans. A substantial literature now points to the importance of dynamic changes in adipocyte and immune cell turnover, angiogenesis, and extracellular matrix remodeling in regulating the expandability and functional integrity of this tissue. In obesity, the macrophages are recruited, surrounding dead adipocytes and polarized toward an inflammatory phenotype. The number of dead adipocytes is closely associated with the pathophysiological consequences of obesity, including insulin resistance and hepatic steatosis. Further, there are substantial depot, sex and species differences in the extent of remodeling. Adipose tissue undergoes a continuous remodeling process that normally maintains tissue health, but may spin out of control and lead to adipocyte death in association with the recruitment and activation of macrophages, and systemic insulin resistance.

  10. Tinnitus: Network pathophysiology-network pharmacology

    Directory of Open Access Journals (Sweden)

    Ana Belen eElgoyhen

    2012-01-01

    Full Text Available Tinnitus, the phantom perception of sound, is a prevalent disorder. One in 10 adults has clinically significant subjective tinnitus, and for 1 in 100, tinnitus severely affects their quality of life. Despite the significant unmet clinical need for a safe and effective drug targeting tinnitus relief, there is currently not a single FDA-approved drug on the market. The search for drugs that target tinnitus is hampered by the lack of a deep knowledge of the underlying neural substrates of this pathology. Recent studies are increasingly demonstrating that, as described for other central nervous system disorders, tinnitus is a pathology of brain networks. The application of graph theoretical analysis to brain networks has recently provided new information concerning their topology, their robustness and their vulnerability to attacks. Moreover, the philosophy behind drug design and pharmacotherapy in central nervous system pathologies is changing from that of magic bullets that target individual chemoreceptors or disease-causing genes into that of magic shotguns, promiscuous or dirty drugs that target disease-causing networks, also known as network pharmacology. In the present work we provide some insight into how this knowledge could be applied to tinnitus pathophysiology and pharmacotherapy.

  11. Hemorrhoids: From basic pathophysiology to clinical management

    Institute of Scientific and Technical Information of China (English)

    Varut Lohsiriwat

    2012-01-01

    This review discusses the pathophysiology,epidemiology,risk factors,classification,clinical evaluation,and current non-operative and operative treatment of hemorrhoids.Hemorrhoids are defined as the symptomatic enlargement and distal displacement of the normal anal cushions.The most common symptom of hemorrhoids is rectal bleeding associated with bowel movement.The abnormal dilatation and distortion of the vascular channel,together with destructive changes in the supporting connective tissue within the anal cushion,is a paramount finding of hemorrhoids.It appears that the dysregulation of the vascular tone and vascular hyperplasia might play an important role in hemorrhoidal development,and could be a potential target for medical treatment.In most instances,hemorrhoids are treated conservatively,using many methods such as lifestyle modification,fiber supplement,suppositorydelivered anti-inflammatory drugs,and administration of venotonic drugs.Non-operative approaches include sclerotherapy and,preferably,rubber band ligation.An operation is indicated when non-operative approaches have failed or complications have occurred.Several surgical approaches for treating hemorrhoids have been introduced including hemorrhoidectomy and stapled hemorrhoidopexy,but postoperative pain is invariable.Some of the surgical treatments potentially cause appreciable morbidity such as anal stricture and incontinence.The applications and outcomes of each treatment are thoroughly discussed.

  12. Orthostatic intolerance: potential pathophysiology and therapy.

    Science.gov (United States)

    Lu, Chih-Cherng; Tseng, Ching-Jiunn; Tang, Hung-Shang; Tung, Che-Se

    2004-09-30

    Orthostatic intolerance affects an estimated 1 in 500 persons and causes a wide range of disabilities. After essential hypertension, it is the most frequently encountered dysautonomia, accounting for the majority of patients referred to centers specializing in autonomic disorders. Patients are typically young females with symptoms such as dizziness, visual changes, head and neck discomfort, poor concentration, fatigue, palpitations, tremulousness, anxiety, and, in some cases, syncope. Syncope is the most hazardous symptom of orthostatic intolerance, presumably occurring because of impaired cerebral perfusion and in part to compensatory autonomic mechanisms. The etiology of this syndrome is still unclear but is heterogeneous. Orthostatic intolerance used to be characterized by an overall enhancement of noradrenergic tone at rest in some patients and by a patchy dysautonomia of postganglionic sympathetic fibers with a compensatory cardiac sympathetic activation in others. However, recent advances in molecular genetics are improving our understanding of orthostatic intolerance, such as several genetic diseases (such as Ehler-Danlos syndrome and norepinephrine transporter deficiency) presenting with symptoms typical of orthostatic intolerance. Future work will include investigation of genetic functional mutations underlying interindividual differences in autonomic cardiovascular control, body fluid regulation, and vascular regulation in orthostatic intolerance patients. The goal of this review article is to describe recent advances in understanding the pathophysiological mechanisms of orthostatic intolerance and their clinical significance.

  13. Pathophysiology and Immune Dysfunction in Endometriosis

    Directory of Open Access Journals (Sweden)

    Soo Hyun Ahn

    2015-01-01

    Full Text Available Endometriosis is an estrogen-dependent, chronic, proinflammatory disease prevalent in 10% of women of reproductive age worldwide. Characterized by the growth of endometrium-like tissue in aberrant locations outside of the uterus, it is responsible for symptoms including chronic pelvic pain, dysmenorrhea, and subfertility that degrade quality of life of women significantly. In Canada, direct and indirect economic cost of endometriosis amounts to 1.8 billion dollars, and this is elevated to 20 billion dollars in the United States. Despite decades of research, the etiology and pathophysiology of endometriosis still remain to be elucidated. This review aims to bring together the current understanding regarding the pathogenesis of endometriosis with specific focus on mechanisms behind vascularization of the lesions and the contribution of immune factors in facilitating lesion establishment and development. The role of hormones, immune cells, and cytokine signaling is highlighted, in addition to discussing the current pharmaceutical options available for management of pain symptoms in women with endometriosis.

  14. Pathophysiology of muscle dysfunction in COPD.

    Science.gov (United States)

    Gea, Joaquim; Agustí, Alvar; Roca, Josep

    2013-05-01

    Muscle dysfunction often occurs in patients with chronic obstructive pulmonary disease (COPD) and may involve both respiratory and locomotor (peripheral) muscles. The loss of strength and/or endurance in the former can lead to ventilatory insufficiency, whereas in the latter it limits exercise capacity and activities of daily life. Muscle dysfunction is the consequence of complex interactions between local and systemic factors, frequently coexisting in COPD patients. Pulmonary hyperinflation along with the increase in work of breathing that occur in COPD appear as the main contributing factors to respiratory muscle dysfunction. By contrast, deconditioning seems to play a key role in peripheral muscle dysfunction. However, additional systemic factors, including tobacco smoking, systemic inflammation, exercise, exacerbations, nutritional and gas exchange abnormalities, anabolic insufficiency, comorbidities and drugs, can also influence the function of both respiratory and peripheral muscles, by inducing modifications in their local microenvironment. Under all these circumstances, protein metabolism imbalance, oxidative stress, inflammatory events, as well as muscle injury may occur, determining the final structure and modulating the function of different muscle groups. Respiratory muscles show signs of injury as well as an increase in several elements involved in aerobic metabolism (proportion of type I fibers, capillary density, and aerobic enzyme activity) whereas limb muscles exhibit a loss of the same elements, injury, and a reduction in fiber size. In the present review we examine the current state of the art of the pathophysiology of muscle dysfunction in COPD.

  15. Hereditary sideroblastic anemias: pathophysiology, diagnosis, and treatment.

    Science.gov (United States)

    Camaschella, Clara

    2009-10-01

    Inherited sideroblastic anemia comprises several rare anemias due to heterogeneous genetic lesions, all characterized by the presence of ringed sideroblasts in the bone marrow. This morphological aspect reflects abnormal mitochondrial iron utilization by the erythroid precursors. The most common X-linked sideroblastic anemia (XLSA), due to mutations of the first enzyme of the heme synthetic pathway, delta-aminolevulinic acid synthase 2 (ALAS2), has linked heme deficiency to mitochondrial iron accumulation. The identification of other genes, such as adenosine triphosphate (ATP) binding cassette B7 (ABCB7) and glutaredoxin 5 (GLRX5), has strengthened the role of iron sulfur cluster biogenesis in sideroblast formation and revealed a complex interplay between pathways of mitochondrial iron utilization and cytosolic iron sensing by the iron-regulatory proteins (IRPs). As recently occurred with the discovery of the SLC25A38-related sideroblastic anemia, the identification of the genes responsible for as yet uncharacterized forms will provide further insights into mitochondrial iron metabolism of erythroid cells and the pathophysiology of sideroblastic anemia.

  16. Catamenial epilepsy: definition, prevalence pathophysiology and treatment.

    Science.gov (United States)

    Herzog, Andrew G

    2008-03-01

    Seizures do not occur randomly. They tend to cluster in the majority of men and women with epilepsy. Seizure clusters, in turn, often show a periodicity. When the periodicity of seizure exacerbation aligns itself with that of the menstrual cycle, it is designated as catamenial epilepsy. The neuroactive properties of reproductive steroids and the cyclic variation in their serum concentrations are important pathophysiologic factors. Recent investigations have demonstrated and confirmed the existence of at least three patterns of catamenial seizure exacerbation: perimenstrual and periovulatory in ovulatory cycles and entire luteal phase in anovulatory cycles. A rational mathematical basis for the categorization of seizure exacerbation as catamenial epilepsy has been developed. It identifies approximately one third of women as having catamenial epilepsy. If seizures show hormonal sensitivity in their occurrence, they may also respond to hormonal treatment. Successful open label trials using cyclic natural progesterone supplement, depomedroxyprogesterone and gonadotropin-releasing hormone analogues in women and using testosterone with or without aromatase inhibitor in men have been reported. Prospective, randomized, placebo-controlled, double-blind investigations are warranted and under way.

  17. Pathophysiology of the antiphospholipid antibody syndrome.

    Science.gov (United States)

    Willis, Rohan; Pierangeli, Silvia S

    2011-11-01

    Antiphospholipid antibodies (aPL) are associated with the recurrent pregnancy loss and thrombosis that characterizes the antiphospholipid antibody syndrome (APS). Although the ontogeny of these pathogenic antibodies has not been fully elucidated, there is evidence that indicates the involvement of both genetic and environmental factors. The ability of aPL to induce a procoagulant phenotype in APS patients plays a central role in the development of arterial and venous thrombotic manifestations typical of the disease. Inflammation serves as a necessary link between this procoagulant phenotype and actual thrombus development and is an important mediator of the placental injury seen in APS patients with obstetric complications. Recent evidence has indicated a role for abnormal cellular proliferation and differentiation in the pathophysiology of APS, especially in those patients with pregnancy morbidity and other more atypical manifestations that have no identifiable thrombotic cause. The interplay of genetic and environmental factors responsible for aPL development and the mechanisms by which these antibodies produce disease in APS patients is the focus of this review.

  18. [Pulmonary rehabilitation: pathophysiology, indications, and clinical efficacy].

    Science.gov (United States)

    Riario Sforza, G G; Incorvaia, C

    2010-01-01

    Pulmonary rehabilitation (PR) is a non pharmacologic treatment of demonstrated efficacy indicated for symptomatic patients with chronic lung diseases. In the pulmonary rehabilitation programs (PRPs), exercise training is a cornerstone component, recommended for improving muscle function. Its aim is to address the disability, intended as the reduction in functional performance and quality of life, derived from muscle deconditioning caused by physical inactivity due to chronic breathlessness, fatigue, and impairment of daily activities claimed by patients with chronic pulmonary diseases. Other components of PRPs are educational, psychosocial and nutritional interventions. Moreover, any PRP should include an outcome assessment, needed for an objective evaluation of program effectiveness, and of patient progress through the time. Although its pivotal role is now accepted worldwide, this was not the prevailing thought during the 1980's and the 1990's, when the pathophysiologic rationale of PR was still not demonstrated, condemning it to be an ancillary treatment to add to standard COPD treatment. The following ascent of PR was mainly due to the number of studies providing its effectiveness, overcoming skepticism and convincing physicians and institutions about its efficacy. Today PR clearly improves exercise tolerance, dyspnea, and quality of life, but despite such demonstration, it is mostly overlooked by health professionals, and only about 2% of patients with COPD undergo to PRPs. A proper consideration of the capability of PR is warranted to ensure optimal management of COPD when the disease causes symptoms and a decrease in physical capacity.

  19. Obesity-related hypertension: possible pathophysiological mechanisms.

    Science.gov (United States)

    Vaněčková, Ivana; Maletínská, Lenka; Behuliak, Michal; Nagelová, Veronika; Zicha, Josef; Kuneš, Jaroslav

    2014-12-01

    Hypertension is one of the major risk factors of cardiovascular diseases, but despite a century of clinical and basic research, the discrete etiology of this disease is still not fully understood. The same is true for obesity, which is recognized as a major global epidemic health problem nowadays. Obesity is associated with an increasing prevalence of the metabolic syndrome, a cluster of risk factors including hypertension, abdominal obesity, dyslipidemia, and hyperglycemia. Epidemiological studies have shown that excess weight gain predicts future development of hypertension, and the relationship between BMI and blood pressure (BP) appears to be almost linear in different populations. There is no doubt that obesity-related hypertension is a multifactorial and polygenic trait, and multiple potential pathogenetic mechanisms probably contribute to the development of higher BP in obese humans. These include hyperinsulinemia, activation of the renin-angiotensin-aldosterone system, sympathetic nervous system stimulation, abnormal levels of certain adipokines such as leptin, or cytokines acting at the vascular endothelial level. Moreover, some genetic and epigenetic mechanisms are also in play. Although the full manifestation of both hypertension and obesity occurs predominantly in adulthood, their roots can be traced back to early ontogeny. The detailed knowledge of alterations occurring in the organism of experimental animals during particular critical periods (developmental windows) could help to solve this phenomenon in humans and might facilitate the age-specific prevention of human obesity-related hypertension. In addition, better understanding of particular pathophysiological mechanisms might be useful in so-called personalized medicine.

  20. The chronobiology, etiology and pathophysiology of obesity.

    Science.gov (United States)

    Garaulet, M; Ordovás, J M; Madrid, J A

    2010-12-01

    The effect of CD on human health is an emerging issue. Many records link CD with diseases such as cancer, cardiovascular, cognitive impairment and obesity, all of them conducive to premature aging. The amount of sleep has declined by 1.5 h over the past century, accompanied by an important increase in obesity. Shift work, sleep deprivation and exposure to bright light at night increase the prevalence of adiposity. Animal models have shown that mice with Clock gene disruption are prone to developing obesity and MetS. This review summarizes the latest developments with regard to chronobiology and obesity, considering (1) how molecular clocks coordinate metabolism and the specific role of the adipocyte; (2) CD and its causes and pathological consequences; (3) the epidemiological evidence of obesity as a chronobiological illness; and (4) theories of circadian disruption and obesity. Energy intake and expenditure, relevance of sleep, fat intake from a circadian perspective and psychological and genetic aspects of obesity are examined. Finally, ideas about the use of chronobiology in the treatment of obesity are discussed. Such knowledge has the potential to become a valuable tool in the understanding of the relationship between the chronobiology, etiology and pathophysiology of obesity.

  1. Whipworms in humans and pigs

    DEFF Research Database (Denmark)

    Hawash, Mohamed Bayoumi Fahmy; Betson, Martha; Al-Jubury, Azmi

    2016-01-01

    -human primates suggesting a common African origin of the parasite, which then was transmitted to Asia and further to South America. On the other hand, there was no differentiation between pig-derived Trichuris from Europe and the New World suggesting dispersal relates to human activities by transporting pigs....... CONCLUSIONS: We found evidence for an African origin of T. trichiura which were then transmitted with human ancestors to Asia and further to South America. A host shift to pigs may have occurred in Asia from where T. suis seems to have been transmitted globally by a combination of natural host dispersal...

  2. Investigation of the disposal of dead pigs by pig farmers in mainland China by simulation experiment.

    Science.gov (United States)

    Wu, Linhai; Xu, Guoyan; Li, Qingguang; Hou, Bo; Hu, Wuyang; Wang, Jianhua

    2017-01-01

    Dead pigs are a major waste by-product of pig farming. Thus, safe disposal of dead pigs is important to the protection of consumer health and the ecological environment by preventing marketing of slaughtered and processed dead pigs and improper dumping of dead pigs. In this study, a probability model was constructed for the disposal of dead pigs by pig farmers by selecting factors affecting disposal. To that end, we drew on the definition and meaning of behavior probability based on survey data collected from 654 pig farmers in Funing County, Jiangsu Province, China. Moreover, the role of influencing factors in pig farmers' behavioral choices regarding the disposal of dead pigs was simulated by simulation experiment. The results indicated that years of farming had a positive impact on pig farmers' choice of negative disposal of dead pigs. Moreover, there was not a simple linear relationship between scale of farming and pig farmers' behavioral choices related to the disposal of dead pigs. The probability for farmers to choose the safe disposal of dead pigs increased with the improvement of their knowledge of government policies and relevant laws and regulations. Pig farmers' behavioral choice about the disposal of dead pigs was also affected by government subsidy policies, regulation, and punishment. Government regulation and punishment were more effective than subsidy. The findings of our simulation experiment provide important decision-making support for the governance in preventing the marketing of dead pigs at the source.

  3. Assessing left ventricular systolic dysfunction after myocardial infarction: are ejection fraction and dP/dt(max) complementary or redundant?

    Science.gov (United States)

    Ishikawa, Kiyotake; Chemaly, Elie R; Tilemann, Lisa; Fish, Kenneth; Ladage, Dennis; Aguero, Jaime; Vahl, Torsten; Santos-Gallego, Carlos; Kawase, Yoshiaki; Hajjar, Roger J

    2012-04-01

    Among the various cardiac contractility parameters, left ventricular (LV) ejection fraction (EF) and maximum dP/dt (dP/dt(max)) are the simplest and most used. However, these parameters are often reported together, and it is not clear if they are complementary or redundant. We sought to compare the discriminative value of EF and dP/dt(max) in assessing systolic dysfunction after myocardial infarction (MI) in swine. A total of 220 measurements were obtained. All measurements included LV volumes and EF analysis by left ventriculography, invasive ventricular pressure tracings, and echocardiography. Baseline measurements were performed in 132 pigs, and 88 measurements were obtained at different time points after MI creation. Receiver operator characteristic (ROC) curves to distinguish the presence or absence of an MI revealed a good predictive value for EF [area under the curve (AUC): 0.998] but not by dP/dt(max) (AUC: 0.69, P EF). Dividing dP/dt(max) by LV end-diastolic pressure and heart rate (HR) significantly increased the AUC to 0.87 (P EF). In naïve pigs, the coefficient of variation of dP/dt(max) was twice than that of EF (22.5% vs. 9.5%, respectively). Furthermore, in n = 19 pigs, dP/dt(max) increased after MI. However, echocardiographic strain analysis of 23 pigs with EF ranging only from 36% to 40% after MI revealed significant correlations between dP/dt(max) and strain parameters in the noninfarcted area (circumferential strain: r = 0.42, P = 0.05; radial strain: r = 0.71, P EF is a more accurate measure of systolic dysfunction than dP/dt(max) in a swine model of MI. Despite the variability of dP/dt(max) both in naïve pigs and after MI, it may sensitively reflect the small changes of myocardial contractility.

  4. Assessment of myocardial adrenergic innervation in patients with sick sinus syndrome: effect of asynchronous ventricular activation from ventricular apical stimulation

    OpenAIRE

    Marketou, M E; Simantirakis, E N; Prassopoulos, V K; Chrysostomakis, S I; Velidaki, A A; Karkavitsas, N S; Vardas, P.E.

    2002-01-01

    Objective: To investigate ventricular sympathetic innervation in patients with sick sinus syndrome and to detect regional deterioration of adrenergic innervation caused by asynchronous ventricular activation from right ventricular pacing.

  5. Impact of the permanent ventricular pacing site on left ventricular function in children: A retrospective multicentre survey

    NARCIS (Netherlands)

    I.E. van Geldorp (Irene); T. Delhaas (Tammo); R.A. Gebauer (Roman); P. Frias (Patrick); M. Tomaske (Maren); M.K. Friedberg (Mark); S. Tisma-Dupanovic (Svjetlana); J. Elders (Jan); A. Früh (Andreas); F. Gabbarini (Fulvio); P. Kubuš (Petr); V. Illikova (Viera); E.C. Tsao (Elisa); A.C. Blank (Andreas Christian); A. Hiippala (Anita); T. Sluysmans (Thierry); P. Karpawich (Peter); S.A. Clur (Sally-Ann); X. Ganame (Xavier); K.K. Collins (Kathryn); G.C. Dann (Greg); J.-B. Thambo (Jean-Benoît); C. Trigo (Conceição); B. Nagel (Bert); J. Papagiannis (John); A. Rackowitz (Annette); J. Marek (Josef); J.-H. Nürnberg (Jan-Hendrik); W.Y. Vanagt (Ward); F.W. Prinzen (Frits); J. Janousek (Jan)

    2011-01-01

    textabstractBackground: Chronic right ventricular (RV) pacing is associated with deleterious effects on cardiac function. Objective In an observational multicentre study in children with isolated atrioventricular (AV) block receiving chronic ventricular pacing, the importance of the ventricular paci

  6. Impact of the permanent ventricular pacing site on left ventricular function in children : a retrospective multicentre survey

    NARCIS (Netherlands)

    van Geldorp, Irene E.; Delhaas, Tammo; Gebauer, Roman A.; Frias, Patrick; Tomaske, Maren; Friedberg, Mark K.; Tisma-Dupanovic, Svjetlana; Elders, Jan; Fruh, Andreas; Gabbarini, Fulvio; Kubus, Petr; Illikova, Viera; Tsao, Sabrina; Blank, Andreas Christian; Hiippala, Anita; Sluysmans, Thierry; Karpawich, Peter; Clur, Sally-Ann; Ganame, Xavier; Collins, Kathryn K.; Dann, Gisela; Thambo, Jean-Benoit; Trigo, Conceicao; Nagel, Bert; Papagiannis, John; Rackowitz, Annette; Marek, Jan; Nuernberg, Jan-Hendrik; Vanagt, Ward Y.; Prinzen, Frits W.; Janousek, Jan

    2011-01-01

    Background Chronic right ventricular (RV) pacing is associated with deleterious effects on cardiac function. Objective In an observational multicentre study in children with isolated atrioventricular (AV) block receiving chronic ventricular pacing, the importance of the ventricular pacing site on le

  7. Pigs in Public Health

    DEFF Research Database (Denmark)

    Svendsen, Mette N.

    2017-01-01

    Animals are rare topics in public health science texts and speech despite the fact that animal bodies and lives are woven into the health of human populations, and vice versa. Years of ethnographic and documentary research – following pigs and their humans in and out of biomedical research – made...... me mindful and watchful of the porous passages between animal and human bodies and environments that do not confine themselves to ‘national health programs’ directed towards a specific (human) population. These unrecognized species encounters and relationships, which exceed the conventional framework...... of public health, made me re-evaluate both what ‘public’ and what ‘health’ means in public health. In this commentary I provide a short personal account of that intellectual journey. I argue that entanglements between species make it urgent that public health scholars investigate the moral, socio...

  8. Guinea pig maximization test

    DEFF Research Database (Denmark)

    Andersen, Klaus Ejner

    1985-01-01

    Guinea pig maximization tests (GPMT) with chlorocresol were performed to ascertain whether the sensitization rate was affected by minor changes in the Freund's complete adjuvant (FCA) emulsion used. Three types of emulsion were evaluated: the oil phase was mixed with propylene glycol, saline...... with 30% (v/v) ethanol or saline, respectively. Relative viscosity was used as one measure of physical properties of the emulsion. Higher degrees of sensitization (but not rates) were obtained at the 48 h challenge reading with the oil/propylene glycol and oil/saline + ethanol emulsions compared...... to the saline/oil emulsion. Placing of the challenge patches affected the response, as simultaneous chlorocresol challenge on the flank located 2 cm closer to the abdomen than the usual challenge site gave decreased reactions....

  9. Thoracic Epidural Anesthesia Reduces Right Ventricular Systolic Function With Maintained Ventricular-Pulmonary Coupling.

    Science.gov (United States)

    Wink, Jeroen; de Wilde, Rob B P; Wouters, Patrick F; van Dorp, Eveline L A; Veering, Bernadette Th; Versteegh, Michel I M; Aarts, Leon P H J; Steendijk, Paul

    2016-10-18

    Blockade of cardiac sympathetic fibers by thoracic epidural anesthesia may affect right ventricular function and interfere with the coupling between right ventricular function and right ventricular afterload. Our main objectives were to study the effects of thoracic epidural anesthesia on right ventricular function and ventricular-pulmonary coupling. In 10 patients scheduled for lung resection, right ventricular function and its response to increased afterload, induced by temporary, unilateral clamping of the pulmonary artery, was tested before and after induction of thoracic epidural anesthesia using combined pressure-conductance catheters. Thoracic epidural anesthesia resulted in a significant decrease in right ventricular contractility (ΔESV25: +25.5 mL, P=0.0003; ΔEes: -0.025 mm Hg/mL, P=0.04). Stroke work, dP/dtMAX, and ejection fraction showed a similar decrease in systolic function (all Pright ventricular contractility increased (ΔESV25: -26.6 mL, P=0.0002; ΔEes: +0.034 mm Hg/mL, P=0.008), but ventricular-pulmonary coupling decreased (Δ(Ees/Ea) = -0.153, Pright ventricular contractility but does not inhibit the native positive inotropic response of the right ventricle to increased afterload. Right ventricular-pulmonary arterial coupling was decreased with increased afterload but not affected by the induction of thoracic epidural anesthesia. URL: http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=2844. Unique identifier: NTR2844. © 2016 American Heart Association, Inc.

  10. Ventricular-Fold Dynamics in Human Phonation

    Science.gov (United States)

    Bailly, Lucie; Bernardoni, Nathalie Henrich; Müller, Frank; Rohlfs, Anna-Katharina; Hess, Markus

    2014-01-01

    Purpose: In this study, the authors aimed (a) to provide a classification of the ventricular-fold dynamics during voicing, (b) to study the aerodynamic impact of these motions on vocal-fold vibrations, and (c) to assess whether ventricular-fold oscillations could be sustained by aerodynamic coupling with the vocal folds. Method: A 72-sample…

  11. Ventricular candidiasis in stone curlews (Burhinus oedicnemus).

    Science.gov (United States)

    Caliendo, Valentina; Bull, Andrew

    2011-09-01

    Ventricular candidiasis is consistently one of the most prominent pathologic conditions diagnosed in stone curlews (Burhinus oedicnemus) in the United Arab Emirates, predominately affecting the captive population. Predisposing factors are a humid environment, stress, immunosuppression, inadequate nutrition, and an extended use of oral antibiotics. In this report, we describe the clinical signs, diagnosis, and pathologic result in stone curlews with ventricular candidiasis.

  12. Structural variations in pig genomes

    NARCIS (Netherlands)

    Paudel, Y.

    2015-01-01

    Abstract Paudel, Y. (2015). Structural variations in pig genomes. PhD thesis, Wageningen University, the Netherlands Structural variations are chromosomal rearrangements such as insertions-deletions (INDELs), duplications, inversions, translocations, and copy number variations (CNVs

  13. Brachyspira murdochii colitis in pigs

    DEFF Research Database (Denmark)

    Jensen, Tim Kåre; Christensen, A. S.; Boye, Mette

    2010-01-01

    The weakly beta-hemolytic porcine spirochete Brachyspira murdochii is considered a normal intestinal commensal. In the present study, however, a field case of B murdochii–associated catarrhal colitis was identified in a pig, as characterized by extensive spirochetal colonization of the surface...... epithelium. Experimentally, 8 weaned pigs were challenged with the B murdochii isolate, reproducing catarrhal colitis in 2 animals. By applying fluorescent in situ hybridization using a species-specific oligonucleotide probe targeting 23S rRNA, B murdochii organisms were found in high numbers and were...... closely associated with the surface epithelium in the pigs with catarrhal colitis. The results indicate that, when present in high numbers, B murdochii is low pathogenic for pigs....

  14. Whipworms in humans and pigs

    DEFF Research Database (Denmark)

    Hawash, Mohamed Bayoumi Fahmy; Betson, Martha; Al-Jubury, Azmi;

    2016-01-01

    BACKGROUND: Trichuris suis and T. trichiura are two different whipworm species that infect pigs and humans, respectively. T. suis is found in pigs worldwide while T. trichiura is responsible for nearly 460 million infections in people, mainly in areas of poor sanitation in tropical and subtropical...... areas. The evolutionary relationship and the historical factors responsible for this worldwide distribution are poorly understood. In this study, we aimed to reconstruct the demographic history of Trichuris in humans and pigs, the evolutionary origin of Trichuris in these hosts and factors responsible...... for parasite dispersal globally. METHODS: Parts of the mitochondrial nad1 and rrnL genes were sequenced followed by population genetic and phylogenetic analyses. Populations of Trichuris examined were recovered from humans (n = 31), pigs (n = 58) and non-human primates (n = 49) in different countries...

  15. Mechanosensitive TRP channels in cardiovascular pathophysiology.

    Science.gov (United States)

    Inoue, Ryuji; Jian, Zhong; Kawarabayashi, Yasuhiro

    2009-09-01

    Transient receptor potential (TRP) proteins constitute a large non-voltage-gated cation channel superfamily, activated polymodally by various physicochemical stimuli, and are implicated in a variety of cellular functions. Known activators for TRP include not only chemical stimuli such as receptor stimulation, increased acidity and pungent/cooling agents, but temperature change and various forms of mechanical stimuli such as osmotic stress, membrane stretch, and shear force. Recent investigations have revealed that at least ten mammalian TRPs exhibit mechanosensitivity (TRPC1, 5, 6; TRPV1, 2, 4; TRPM3, 7; TRPA1; TRPP2), but the mechanisms underlying it appear considerably divergent and complex. The proposed mechanisms are associated with lipid bilayer mechanics, specialized force-transducing structures, biochemical reactions, membrane trafficking and transcriptional regulation. Many of mechanosensitive (MS)-TRP channel likely undergo multiple regulations via these mechanisms. In the cardiovascular system in which hemodynamic forces constantly operate, the impact of mechanical stress may be particularly significant. Extensive morphological and functional studies have indicated that several MS-TRP channels are expressed in cardiac muscle, vascular smooth muscle, endothelium and vasosensory neurons, each differentially contributing to cardiovascular (CV) functions. To further complexity, the recent evidence suggests that mechanical stress may synergize with neurohormonal mechanisms thereby amplifying otherwise marginal responses. Furthermore, the currently available data suggest that MS-TRP channels may be involved in CV pathophysiology such as cardiac arrhythmia, cardiac hypertrophy/myopathy, hypertension and aneurysms. This review will overview currently known mechanisms for mechanical activation/modulation of TRPs and possible connections of MS-TRP channels to CV disorders.

  16. Leptin in human physiology and pathophysiology.

    Science.gov (United States)

    Mantzoros, Christos S; Magkos, Faidon; Brinkoetter, Mary; Sienkiewicz, Elizabeth; Dardeno, Tina A; Kim, Sang-Yong; Hamnvik, Ole-Petter R; Koniaris, Anastasia

    2011-10-01

    Leptin, discovered through positional cloning 15 years ago, is an adipocyte-secreted hormone with pleiotropic effects in the physiology and pathophysiology of energy homeostasis, endocrinology, and metabolism. Studies in vitro and in animal models highlight the potential for leptin to regulate a number of physiological functions. Available evidence from human studies indicates that leptin has a mainly permissive role, with leptin administration being effective in states of leptin deficiency, less effective in states of leptin adequacy, and largely ineffective in states of leptin excess. Results from interventional studies in humans demonstrate that leptin administration in subjects with congenital complete leptin deficiency or subjects with partial leptin deficiency (subjects with lipoatrophy, congenital or related to HIV infection, and women with hypothalamic amenorrhea) reverses the energy homeostasis and neuroendocrine and metabolic abnormalities associated with these conditions. More specifically, in women with hypothalamic amenorrhea, leptin helps restore abnormalities in hypothalamic-pituitary-peripheral axes including the gonadal, thyroid, growth hormone, and to a lesser extent adrenal axes. Furthermore, leptin results in resumption of menses in the majority of these subjects and, in the long term, may increase bone mineral content and density, especially at the lumbar spine. In patients with congenital or HIV-related lipoatrophy, leptin treatment is also associated with improvements in insulin sensitivity and lipid profile, concomitant with reduced visceral and ectopic fat deposition. In contrast, leptin's effects are largely absent in the obese hyperleptinemic state, probably due to leptin resistance or tolerance. Hence, another emerging area of research pertains to the discovery and/or usefulness of leptin sensitizers. Results from ongoing studies are expected to further increase our understanding of the role of leptin and the potential clinical

  17. Altered Mitochondrial Dynamics and TBI Pathophysiology

    Directory of Open Access Journals (Sweden)

    Tara Diane Fischer

    2016-03-01

    Full Text Available Mitochondrial function is intimately linked to cellular survival, growth, and death. Mitochondria not only generate ATP from oxidative phosphorylation, but also mediate intracellular calcium buffering, generation of reactive oxygen species (ROS, and apoptosis. Electron leakage from the electron transport chain, especially from damaged or depolarized mitochondria, can generate excess free radicals that damage cellular proteins, DNA, and lipids. Furthermore, mitochondrial damage releases pro-apoptotic factors to initiate cell death. Previous studies have reported that traumatic brain injury (TBI reduces mitochondrial respiration, enhances production of ROS, and triggers apoptotic cell death, suggesting a prominent role of mitochondria in TBI pathophysiology. Mitochondria maintain cellular energy homeostasis and health via balanced processes of fusion and fission, continuously dividing and fusing to form an interconnected network throughout the cell. An imbalance of these processes, particularly an excess of fission, can be detrimental to mitochondrial function, causing decreased respiration, ROS production, and apoptosis. Mitochondrial fission is regulated by the cytosolic GTPase, dynamin-related protein 1 (Drp1, which translocates to the mitochondrial outer membrane to initiate fission. Aberrant Drp1 activity has been linked to excessive mitochondrial fission and neurodegeneration. Measurement of Drp1 levels in purified hippocampal mitochondria showed an increase in TBI animals as compared to sham controls. Analysis of cryo-electron micrographs of these mitochondria also showed that TBI caused an initial increase in the length of hippocampal mitochondria at 24 hours post-injury, followed by a significant decrease in length at 72 hours. Post-TBI administration of Mdivi-1, a pharmacological inhibitor of Drp1, prevented this decrease in mitochondria length. Mdivi-1 treatment also reduced the loss of newborn neurons in the hippocampus and improved

  18. Leptin in human physiology and pathophysiology

    Science.gov (United States)

    Magkos, Faidon; Brinkoetter, Mary; Sienkiewicz, Elizabeth; Dardeno, Tina A.; Kim, Sang-Yong; Hamnvik, Ole-Petter R.; Koniaris, Anastasia

    2011-01-01

    Leptin, discovered through positional cloning 15 years ago, is an adipocyte-secreted hormone with pleiotropic effects in the physiology and pathophysiology of energy homeostasis, endocrinology, and metabolism. Studies in vitro and in animal models highlight the potential for leptin to regulate a number of physiological functions. Available evidence from human studies indicates that leptin has a mainly permissive role, with leptin administration being effective in states of leptin deficiency, less effective in states of leptin adequacy, and largely ineffective in states of leptin excess. Results from interventional studies in humans demonstrate that leptin administration in subjects with congenital complete leptin deficiency or subjects with partial leptin deficiency (subjects with lipoatrophy, congenital or related to HIV infection, and women with hypothalamic amenorrhea) reverses the energy homeostasis and neuroendocrine and metabolic abnormalities associated with these conditions. More specifically, in women with hypothalamic amenorrhea, leptin helps restore abnormalities in hypothalamic-pituitary-peripheral axes including the gonadal, thyroid, growth hormone, and to a lesser extent adrenal axes. Furthermore, leptin results in resumption of menses in the majority of these subjects and, in the long term, may increase bone mineral content and density, especially at the lumbar spine. In patients with congenital or HIV-related lipoatrophy, leptin treatment is also associated with improvements in insulin sensitivity and lipid profile, concomitant with reduced visceral and ectopic fat deposition. In contrast, leptin's effects are largely absent in the obese hyperleptinemic state, probably due to leptin resistance or tolerance. Hence, another emerging area of research pertains to the discovery and/or usefulness of leptin sensitizers. Results from ongoing studies are expected to further increase our understanding of the role of leptin and the potential clinical

  19. Altered Mitochondrial Dynamics and TBI Pathophysiology.

    Science.gov (United States)

    Fischer, Tara D; Hylin, Michael J; Zhao, Jing; Moore, Anthony N; Waxham, M Neal; Dash, Pramod K

    2016-01-01

    Mitochondrial function is intimately linked to cellular survival, growth, and death. Mitochondria not only generate ATP from oxidative phosphorylation, but also mediate intracellular calcium buffering, generation of reactive oxygen species (ROS), and apoptosis. Electron leakage from the electron transport chain, especially from damaged or depolarized mitochondria, can generate excess free radicals that damage cellular proteins, DNA, and lipids. Furthermore, mitochondrial damage releases pro-apoptotic factors to initiate cell death. Previous studies have reported that traumatic brain injury (TBI) reduces mitochondrial respiration, enhances production of ROS, and triggers apoptotic cell death, suggesting a prominent role of mitochondria in TBI pathophysiology. Mitochondria maintain cellular energy homeostasis and health via balanced processes of fusion and fission, continuously dividing and fusing to form an interconnected network throughout the cell. An imbalance of these processes, particularly an excess of fission, can be detrimental to mitochondrial function, causing decreased respiration, ROS production, and apoptosis. Mitochondrial fission is regulated by the cytosolic GTPase, dynamin-related protein 1 (Drp1), which translocates to the mitochondrial outer membrane (MOM) to initiate fission. Aberrant Drp1 activity has been linked to excessive mitochondrial fission and neurodegeneration. Measurement of Drp1 levels in purified hippocampal mitochondria showed an increase in TBI animals as compared to sham controls. Analysis of cryo-electron micrographs of these mitochondria also showed that TBI caused an initial increase in the length of hippocampal mitochondria at 24 h post-injury, followed by a significant decrease in length at 72 h. Post-TBI administration of Mitochondrial division inhibitor-1 (Mdivi-1), a pharmacological inhibitor of Drp1, prevented this decrease in mitochondria length. Mdivi-1 treatment also reduced the loss of newborn neurons in the

  20. [Ventricular tachyarrhythmias in patients with cardiomyopathy

    DEFF Research Database (Denmark)

    Henningsen, K.; Christensen, A.H.; Svendsen, Jesper Hastrup

    2008-01-01

    of patients discharged with the diagnostic codes ventricular tachycardia, ventricular fibrillation or premature ventricular contractions with cardiomyopathy as the presumed aetiology. Patients discharged during a period of 6 years and 5 months were included in the study. The patients were characterized......INTRODUCTION: The purpose of this study was to determine the number and distribution of cardiomyopathies as the aetiology of ventricular tachyarrhythmias among patients discharged from the Department of Cardiology, Rigshospitalet. MATERIALS AND METHODS: The study was a retrospective review......), 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...

  1. Giant and thrombosed left ventricular aneurysm

    Institute of Scientific and Technical Information of China (English)

    Jose; Alberto; de; Agustin; Jose; Juan; Gomez; de; Diego; Pedro; Marcos-Alberca; Jose; Luis; Rodrigo; Carlos; Almeria; Patricia; Mahia; Maria; Luaces; Miguel; Angel; Garcia-Fernandez; Carlos; Macaya; Leopoldo; Perez; de; Isla

    2015-01-01

    Left ventricular aneurysms are a frequent complication of acute extensive myocardial infarction and are most commonly located at the ventricular apex. A timely diagnosis is vital due to the serious complications that can occur,including heart failure,thromboembolism,or tachyarrhythmias. We report the case of a 78-yearold male with history of previous anterior myocardial infarction and currently under evaluation by chronic heart failure. Transthoracic echocardiogram revealed a huge thrombosed and calcified anteroapical left ventricular aneurysm. Coronary angiography demonstrated that the left anterior descending artery was chronically occluded,and revealed a big and spherical mass with calcified borders in the left hemithorax. Left ventriculogram confirmed that this spherical mass was a giant calcified left ventricular aneurysm,causing very severe left ventricular systolic dysfunction. The patient underwent cardioverter-defibrillator implantation for primary prevention.

  2. Giant and thrombosed left ventricular aneurysm.

    Science.gov (United States)

    de Agustin, Jose Alberto; de Diego, Jose Juan Gomez; Marcos-Alberca, Pedro; Rodrigo, Jose Luis; Almeria, Carlos; Mahia, Patricia; Luaces, Maria; Garcia-Fernandez, Miguel Angel; Macaya, Carlos; de Isla, Leopoldo Perez

    2015-07-26

    Left ventricular aneurysms are a frequent complication of acute extensive myocardial infarction and are most commonly located at the ventricular apex. A timely diagnosis is vital due to the serious complications that can occur, including heart failure, thromboembolism, or tachyarrhythmias. We report the case of a 78-year-old male with history of previous anterior myocardial infarction and currently under evaluation by chronic heart failure. Transthoracic echocardiogram revealed a huge thrombosed and calcified anteroapical left ventricular aneurysm. Coronary angiography demonstrated that the left anterior descending artery was chronically occluded, and revealed a big and spherical mass with calcified borders in the left hemithorax. Left ventriculogram confirmed that this spherical mass was a giant calcified left ventricular aneurysm, causing very severe left ventricular systolic dysfunction. The patient underwent cardioverter-defibrillator implantation for primary prevention.

  3. A short review on the aetiology and pathophysiology of alcoholism

    Directory of Open Access Journals (Sweden)

    Douzenis Athanassios

    2009-05-01

    Full Text Available Abstract Alcoholism is a chronic remitting and relapsing condition; its aetiology and pathophysiology remains largely obscure despite recent advances. This review summarises the current knowledge about the causation (biological or psychological of alcohol addiction. This involves heredity, candidate genes, alcohol metabolism regulation and the influence of alcohol in the pathophysiology of the different neurotransmitter systems. Alcohol addiction is a multifactorial phenomenon where personality structure, individual state of mind and social influences are in constant interaction with brain neurobiology and pathophysiology. This disorder influences different sexes in different ways and causes major problems, especially in developed societies.

  4. Pathophysiology of Pulmonary Hypertension in Chronic Parenchymal Lung Disease.

    Science.gov (United States)

    Singh, Inderjit; Ma, Kevin Cong; Berlin, David Adam

    2016-04-01

    Pulmonary hypertension commonly complicates chronic obstructive pulmonary disease and interstitial lung disease. The association of chronic lung disease and pulmonary hypertension portends a worse prognosis. The pathophysiology of pulmonary hypertension differs in the presence or absence of lung disease. We describe the physiological determinants of the normal pulmonary circulation to better understand the pathophysiological factors implicated in chronic parenchymal lung disease-associated pulmonary hypertension. This review will focus on the pathophysiology of 3 forms of chronic lung disease-associated pulmonary hypertension: idiopathic pulmonary fibrosis, chronic obstructive pulmonary disease, and sarcoidosis. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Arterial stiffness: pathophysiology and clinical impact.

    Science.gov (United States)

    London, Gérard M; Marchais, Sylvain J; Guerin, Alain P; Pannier, Bruno

    2004-01-01

    The ill effects of hypertension are usually attributed to a reduction in the caliber or the number of arterioles, resulting in an increase in total peripheral resistance (TPR). This definition does not take into account the fact that BP is a cyclic phenomenon with systolic and diastolic BP being the limits of these oscillations. The appropriate term to define the arterial factor(s) opposing LV ejection is aortic input impedance which depends on TPR, arterial distensibility (D), and wave reflections (WR). D defines the capacitive properties of arterial stiffness, whose role is to dampen pressure and flow oscillations and to transform pulsatile flow and pressure in arteries into a steady flow and pressure in peripheral tissues. Stiffness is the reciprocal value of D. These parameters are BP dependent, and arteries become stiffer at high pressure. In to D which provides information about the elasticity> of artery as a hollow structure, the elastic incremental modulus (Einc) characterizes the properties of the arterial wall biomaterials, independently of vessel geometry. As an alternative, arterial D can be evaluated by measuring the pulse wave velocity (PWV) which increases with the stiffening of arteries. Arterial stiffening increases left ventricular (LV) afterload and alters the coronary perfusion. With increased PWV, the WR impacts on the aorta during systole, increasing systolic pressures and myocardial oxygen consumption, and decreasing diastolic BP and coronary flow. The arterial stiffness is altered primarily in association with increased collagen content and alterations of extracellular matrix (arteriosclerosis) as classically observed during aging or in arterial hypertension. The arterial stiffening estimated by changes in aortic PWV and intensity of WR are independent predictors of survival in end stage renal disease (ESRD) and general population. Improvement of arterial stiffening could be obtained by antihypertensive treatmen as observed with the calcium

  6. DMPD: Pathophysiological roles of interleukin-18 in inflammatory liver diseases. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 10807517 Pathophysiological roles of interleukin-18 in inflammatory liver diseases....l) Show Pathophysiological roles of interleukin-18 in inflammatory liver diseases. PubmedID 10807517 Title Pathophysiological role

  7. A Novel Method in the Stratification of Post-Myocardial-Infarction Patients Based on Pathophysiology.

    Directory of Open Access Journals (Sweden)

    Ben He

    Full Text Available We proposed that the severity of ST-segment elevation myocardial infarction (STEMI could be classified based on pathophysiological changes.First-STEMI patients were classified within hospitalization. Grade 0: no detectable myocardial necrosis; Grade 1: myocardial necrosis without functional and morphological abnormalities; Grade 2: myocardial necrosis with reduced LVEF; Grade 3: reduced LVEF on the basis of cardiac remodeling; Grade 4: mitral regurgitation additional to the Grade-3 criteria.Of 180 patients, 1.7, 43.9, 26.1, 23.9 and 4.4% patients were classified as Grade 0 to 4, respectively. The classification is an independent predicator of 90-day MACEs (any death, resuscitated cardiac arrest, acute heart failure and stroke: the rate was 0, 5.1, 8.5, 48.8 and 75% from Grade 0 to 4 (p < 0.001, respectively. The Grade-2 patients were more likely to have recovered left ventricular ejection fraction than the Grade-3/4 patients did after 90 days (48.9% vs. 19.1%, p < 0.001. Avoiding complicated quantification, the classification served as a good reflection of infarction size as measured by cardiac magnetic resonance imaging (0 ± 0, 15.68 ± 8.48, 23.68 ± 9.32, 36.12 ± 11.35 and 40.66 ± 14.33% of the left ventricular mass by Grade 0 to 4, P < 0.001, and with a comparable prognostic value (AUC 0.819 vs. 0.813 for infarction size, p = 0.876 by C-statistics for MACEs.The new classification represents an easy and objective method to scale the cardiac detriments for STEMI patients.

  8. Heart Failure with Preserved Ejection Fraction – Concept, Pathophysiology, Diagnosis and Challenges for Treatment

    Directory of Open Access Journals (Sweden)

    Lidija Veterovska Miljkovik

    2015-07-01

    Full Text Available Heart failure (HF with preserved left ventricular (LV ejection fraction (HFpEF occurs in 40 to 60% of the patients with HF, with a prognosis which is similar to HF with reduced ejection fraction (HFrEF. HFpEF pathophysiology is different from that of HFrEF, and has been characterized with diastolic dysfunction. Diastolic dysfunction has been defined with elevated left ventricular stiffness, prolonged iso-volumetric LV relaxation, slow LV filing and elevated LV end-diastolic pressure. Arterial hypertension occurs in majority cases with HFpEF worldwide. Patients are mostly older and obese. Diabetes mellitus and atrial fibrillation appear proportionally in a high frequency of patients with HFpEF. The HFpEF diagnosis is based on existence of symptoms and signs of heart failure, normal or approximately normal ejection and diagnosing of LV diastolic dysfunction by means of heart catheterization or Doppler echocardiography and/or elevated concentration of plasma natriuretic peptide. The present recommendations for HFpEF treatment include blood pressure control, heart chamber frequency control when atrial fibrillation exists, in some situations even coronary revascularization and an attempt for sinus rhythm reestablishment. Up to now, it is considered that no medication or a group of medications improve the survival of HFpEF patients. Due to these causes and the bad prognosis of the disorder, rigorous control is recommended of the previously mentioned precipitating factors for this disorder. This paper presents a universal review of the most important parameters which determine this disorder.

  9. Delirium in Critically Ill Patients Epidemiology, Pathophysiology, Diagnosis and Management

    NARCIS (Netherlands)

    Zaal, Irene J.; Slooter, Arjen J. C.

    2012-01-01

    Delirium is commonly observed in critically ill patients and is associated with negative outcomes. The pathophysiology of delirium is not completely understood. However, alterations to neurotransmitters, especially acetylcholine and dopamine, inflammatory pathways and an aberrant stress response are

  10. Visceral hypersensitivity in Irritable Bowel Syndrome:pathophysiological mechanisms

    NARCIS (Netherlands)

    Kerckhoffs, A.P.M.

    2009-01-01

    Irritable Bowel Syndrome (IBS) is a functional bowel disease characterized by abdominal pain or discomfort associated with a disordered defecation. No unique pathophysiological mechanism has been identified. It is most likely a multifactorial disease involving alterations in intestinal microbiota

  11. Automated left ventricular capture management.

    Science.gov (United States)

    Crossley, George H; Mead, Hardwin; Kleckner, Karen; Sheldon, Todd; Davenport, Lynn; Harsch, Manya R; Parikh, Purvee; Ramza, Brian; Fishel, Robert; Bailey, J Russell

    2007-10-01

    The stimulation thresholds of left ventricular (LV) leads tend to be less reliable than conventional leads. Cardiac resynchronization therapy (CRT) requires continuous capture of both ventricles. The purpose of this study is to evaluate a novel algorithm for the automatic measurement of the stimulation threshold of LV leads in cardiac resynchronization systems. We enrolled 134 patients from 18 centers who had existing CRT-D systems. Software capable of automatically executing LV threshold measurements was downloaded into the random access memory (RAM) of the device. The threshold was measured by pacing in the left ventricle and analyzing the interventricular conduction sensed in the right ventricle. Automatic LV threshold measurements were collected and compared with manual LV threshold tests at each follow-up visit and using a Holter monitor system that recorded both the surface electrocardiograph (ECG) and continuous telemetry from the device. The proportion of Left Ventricular Capture Management (LVCM) in-office threshold tests within one programming step of the manual threshold test was 99.7% (306/307) with a two-sided 95% confidence interval of (98.2%, 100.0%). The algorithm measured the threshold successfully in 96% and 97% of patients after 1 and 3 months respectively. Holter monitor analysis in a subset of patients revealed accurate performance of the algorithm. This study demonstrated that the LVCM algorithm is safe, accurate, and highly reliable. LVCM worked with different types of leads and different lead locations. LVCM was demonstrated to be clinically equivalent to the manual LV threshold test. LVCM offers automatic measurement, output adaptation, and trends of the LV threshold and should result in improved ability to maintain LV capture without sacrificing device longevity.

  12. Pathophysiology of reversible sudden deafness--epidemiological study.

    OpenAIRE

    Ohsaki, Katsuichiro; Aoyama, Hideyasu

    1983-01-01

    Many aspects of the etiology and pathophysiology of reversible sudden deafness remain obscure. In order to better understand the pathophysiology of reversible sudden deafness we compared the results of two therapies which have different mechanisms of action. The results of therapy with tranexamic acid alone in 49 cases (57 ears) of sudden deafness were compared with the results of treatment with so-called antisludging agents in 65 cases (69 ears) using the chi square contingency test. The sam...

  13. Adaptive Immune Responses Regulate the Pathophysiology of Lymphedema

    Science.gov (United States)

    2012-09-01

    Pathophysiology of Lymphedema PRINCIPAL INVESTIGATOR: Jamie Zampell, M.D. CONTRACTING ORGANIZATION: Sloan-Kettering Institute for...Immune Responses Regulate the Pathophysiology of Lymphedema 5a. CONTRACT NUMBER 5b. GRANT NUMBER W81XWH-11-1-0495 5c. PROGRAM ELEMENT... Lymphedema is a debilitating disorder affecting as many as 1 in 8 cancer survivors. Despite wide prevalence, limited understanding of disease

  14. Teaching pathophysiology: strategies to enliven the traditional lecture.

    Science.gov (United States)

    Van Horn, Elizabeth R; Hyde, Yolanda M; Tesh, Anita S; Kautz, Donald D

    2014-01-01

    The depth and breadth of pathophysiology content, foundational for nursing practice, is well suited for traditional lecture delivery. Use of creative strategies can deepen students' understanding while respecting students' diverse talents and ways of learning. The authors discuss strategies they used, including case studies, questions asked during lecture using immediate feedback technology, creative visual demonstrations, group pathophysiologic theory projects, short videos, and games, to enhance students' understanding and retention of content.

  15. Major Pathophysiological Correlations of Rosacea: A Complete Clinical Appraisal

    OpenAIRE

    Vemuri, Ravi Chandra; Gundamaraju, Rohit; Sekaran, Shamala Devi; Manikam, Rishya

    2015-01-01

    Background: Rosacea is a characteristic cutaneous disorder with a diverse clinical manifestations ranging from facial vascular hyper-reactivity to sebaceous gland hyperplasia. Many theories on pathophysiology of rosacea were proposed over the past decade, however the pathogenicity is poorly understood. Aim: To review the evidence on different pathophysiological correlations of rosacea. Methods: A literature search was conducted for studies published between 1990 to March 2014. The inclusion c...

  16. Pathophysiology of acute small bowel disease with CT correlation

    Energy Technology Data Exchange (ETDEWEB)

    Sarwani, N., E-mail: nsarwani@hmc.psu.ed [Department of Radiology, Section of Abdominal Imaging, Penn State Milton Hershey Medical Center, Hershey, PA (United States); Tappouni, R.; Tice, J. [Department of Radiology, Section of Abdominal Imaging, Penn State Milton Hershey Medical Center, Hershey, PA (United States)

    2011-01-15

    The objective of this article is to review the pathophysiology of acute small bowel diseases, and to correlate the mechanisms of disease with computed tomography (CT) findings. Disease entities will be classified into the following: immune mediated and infectious causes, vascular causes, mechanical causes, trauma, and others. Having an understanding of acute small bowel pathophysiology is a useful teaching tool, and can lead to imaging clues to the most likely diagnosis of acute small bowel disorders.

  17. Pathophysiology of reversible sudden deafness--epidemiological study.

    OpenAIRE

    Ohsaki, Katsuichiro; Aoyama, Hideyasu

    1983-01-01

    Many aspects of the etiology and pathophysiology of reversible sudden deafness remain obscure. In order to better understand the pathophysiology of reversible sudden deafness we compared the results of two therapies which have different mechanisms of action. The results of therapy with tranexamic acid alone in 49 cases (57 ears) of sudden deafness were compared with the results of treatment with so-called antisludging agents in 65 cases (69 ears) using the chi square contingency test. The sam...

  18. Serological evidence of hepatitis E virus infection in pigs and jaundice among pig handlers in Bangladesh

    DEFF Research Database (Denmark)

    Haider, Najmul; Khan, M. S. U.; Hossain, M. B.

    2017-01-01

    Hepatitis E virus (HEV) is the most common cause of viral hepatitis in humans. Pigs may act as a reservoir of HEV, and pig handlers were frequently identified with a higher prevalence of antibodies to HEV. The objectives of this study were to identify evidence of HEV infection in pigs and compare...... with jaundice in the past 2 years. Pigs in Bangladesh demonstrated evidence of HEV infec-tion, and a history of jaundice was significantly more frequent in pig handlers. Identifying and genotyping HEV in pigs and pig handlers may provide further evidence of the pig’s role in zoonotic HEV transmission...

  19. Metabolomic phenotyping of a cloned pig model

    DEFF Research Database (Denmark)

    Clausen, Morten Rahr; Christensen, Kirstine Lykke; Hedemann, Mette Skou

    2011-01-01

    and possibly also phenotypes and this offer an extra level of experimental control which could possibly make them a desirable tool for intervention studies. Therefore, in the present study, we address how phenotype and phenotypic variation is affected by cloning, through comparison of cloned pigs and normal...... outbred pigs. Results The metabolic phenotype of cloned pigs (n = 5) was for the first time elucidated by nuclear magnetic resonance (NMR)-based metabolomic analysis of multiple bio-fluids including plasma, bile and urine. The metabolic phenotype of the cloned pigs was compared with normal outbred pigs (n...... = 6) by multivariate data analysis, which revealed differences in the metabolic phenotypes. Plasma lactate was higher for cloned vs control pigs, while multiple metabolites were altered in the bile. However a lower inter-individual variability for cloned pigs compared with control pigs could...

  20. Influence of acute glycaemic level on measures of myocardial infarction in non-diabetic pigs

    DEFF Research Database (Denmark)

    Diemar, Sarah S; Sejling, Anne-Sophie; Iversen, Kasper K

    2015-01-01

    OBJECTIVE: Patients with diabetes are at increased risk of experiencing myocardial infarction. The influence of the prevailing plasma glucose level on infarction and mortality after acute ischaemia is however unknown. The aim was to study the effect of the acute plasma glucose level......) in the hyperglycaemic group, with no differences in infarction size, infarct/area at risk ratio or troponin T levels between the groups. There was no difference in incidence of ventricular fibrillation or mortality between the groups. CONCLUSION: No statistically significant associations were observed between the acute...... on the myocardial infarction size in a closed-chest pig model. DESIGN: 38 non-diabetic pigs were randomised to hypoglycaemic (1.8-2.2 mmol/l; n = 15), normoglycaemic (5-7 mmol/l; n = 12) or hyperglycaemic glucose clamping (22-23 mmol/l; n = 11). After 30 min within glucose target myocardial infarction was induced...

  1. 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.

  2. Experimental aerosolized guinea pig-adapted Zaire ebolavirus (variant: Mayinga) causes lethal pneumonia in guinea pigs.

    Science.gov (United States)

    Twenhafel, N A; Shaia, C I; Bunton, T E; Shamblin, J D; Wollen, S E; Pitt, L M; Sizemore, D R; Ogg, M M; Johnston, S C

    2015-01-01

    Eight guinea pigs were aerosolized with guinea pig-adapted Zaire ebolavirus (variant: Mayinga) and developed lethal interstitial pneumonia that was distinct from lesions described in guinea pigs challenged subcutaneously, nonhuman primates challenged by the aerosol route, and natural infection in humans. Guinea pigs succumbed with significant pathologic changes primarily restricted to the lungs. Intracytoplasmic inclusion bodies were observed in many alveolar macrophages. Perivasculitis was noted within the lungs. These changes are unlike those of documented subcutaneously challenged guinea pigs and aerosolized filoviral infections in nonhuman primates and human cases. Similar to findings in subcutaneously challenged guinea pigs, there were only mild lesions in the liver and spleen. To our knowledge, this is the first report of aerosol challenge of guinea pigs with guinea pig-adapted Zaire ebolavirus (variant: Mayinga). Before choosing this model for use in aerosolized ebolavirus studies, scientists and pathologists should be aware that aerosolized guinea pig-adapted Zaire ebolavirus (variant: Mayinga) causes lethal pneumonia in guinea pigs.

  3. Method for quantifiying conduction velocity during ventricular fibrillation

    Science.gov (United States)

    Mourad, Ayman; Nash, Martyn P.

    2007-01-01

    Velocity of propagation of electrical excitation in the heart is important for the understanding of complex arrhythmias such as ventricular fibrillation (VF). In this paper, we present a method to estimate the conduction velocity of electrical activation wavefronts that are defined to be a particular isovalue of any scalar field, such as electrical activation times, electrical phase, or indeed any other quantity that can be used to determine excitation wavefronts. This general method is based on tracking trajectories of material points that are assumed to be embedded within the wavefronts, whilst the direction of propagation is assumed to be perpendicular to the wavefront. We have derived an explicit expression for the conduction velocity in terms of the spatiotemporal gradients of the scalar field used to define wavefronts. Moreover, although it is often difficult to use activation times to compute conduction velocities during complex VF, we show that other scalar fields such as detrended voltage or electrical phase, which can faithfully represent the electrical activity during fibrillatory conduction, can be used to determine conduction velocities. We demonstrate the application of our method to determine conduction velocities from contact mapping recordings over the entire epicardial surface of the fibrillating pig heart.

  4. Role of novel DSP_p.Q986X genetic variation in arrhythmogenic right ventricular cardiomyopathy.

    Science.gov (United States)

    Campuzano, Oscar; Alcalde, Mireia; Berne, Paola; Zorio, Esther; Iglesias, Anna; Navarro-Manchón, Josep; Brugada, Josep; Brugada, Ramon

    2013-10-01

    Arrhythmogenic right ventricular cardiomyopathy is an inherited disease characterized by a progressive myocardium fibrofatty replacement. This abnormality disrupts electrical transmission causing ventricular arrhythmias and sudden cardiac death. This genetic disease is transmitted mainly with an autosomal dominant pattern. Our aim was to identify the genetic defect responsible for the pathology in a Spanish family, and to perform its phenotype connotations. A total of 15 individuals in a three-generation Spanish family were screened after the sudden cardiac death of one family member. All they underwent a complete physical examination, 12-lead electrocardiogram, 2-dimensional echocardiography, magnetic resonance imaging, exercise stress test, 24-h Holter and genetic testing. Autopsy revealed the presence of biventricular arrhythmogenic dysplasia in deceased member. Six family members showed clinical symptoms but only three of them fulfilled definite diagnostic criteria of the disease. Genetic analysis showed a novel nonsense genetic variation in nine family members. All family members with clinical symptoms carried the genetic variation. Genetic testing in families affected by arrhythmogenic right ventricular cardiomyopathy helps to identify the genetic cause responsible for the disease. The incomplete penetrance and variable phenotypic expression highlights the need of comprehensive genetic analysis and further phenotype implications of genetics to clarify the pathophysiology of the disease. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  5. Ventricular fibrillation via torsade des pointes of cardiac sarcoidosis with preserved left ventricular ejection fraction.

    Science.gov (United States)

    Sekihara, Takayuki; Nakane, Eisaku; Nakasone, Kazutaka; Inoko, Moriaki

    2016-10-25

    Generally, low left ventricular ejection fraction (LVEF) is a risk for ventricular arrhythmia in patients with cardiac sarcoidosis. We present a case of cardiac sarcoidosis with preserved LVEF that evoked ventricular fibrillation (VF). A 73-year-old woman with VF presented to our emergency department. She had a history of ocular sarcoidosis, with gradual thinning of the basal intraventricular septum. LVEF was 62% on the most recent echocardiography. The electrocardiogram after defibrillation showed complete atrioventricular block (CAVB) with QT segment prolongation and frequent ventricular premature beats. VF via torsade des pointes (TdP) was suspected, and temporary intravenous ventricular pacing and magnesium sulfate infusion suppressed her VF. Cardiac sarcoidosis was diagnosed, and an implantable cardioverter defibrillator was implanted. Patients with cardiac sarcoidosis with CAVB are at risk of evoking VF via TdP regardless of LVEF. If cardiac sarcoidosis is suspected, early diagnosis and risk stratification of ventricular arrhythmia are important. 2016 BMJ Publishing Group Ltd.

  6. Pathophysiology and a Rational Basis of Therapy.

    Science.gov (United States)

    Gracia-Sancho, Jordi; Maeso-Díaz, Raquel; Bosch, Jaime

    2015-01-01

    sufficiently to promote the development of intrahepatic shunts and portal-systemic collaterals, including varices, through which portal blood flow bypasses the liver. In human portal hypertension collateralization and hyperdynamic circulation start at a portal pressure gradient >10 mm Hg. Rational therapy for portal hypertension aims at correcting these pathophysiological abnormalities: liver injury, fibrogenesis, increased hepatic vascular tone and splanchnic vasodilatation. Continuing liver injury may be counteracted specifically by etiological treatments (the best example being the direct-acting antivirals for hepatitis C viral infection), while architectural disruption and fibrosis can be ameliorated by a variety of antifibrotic drugs and antiangiogenic strategies. Several drugs in this category are currently under investigation in phase II-III randomized controlled trials. Sinusoidal endothelial dysfunction is ameliorated by statins as well as by other drugs increasing NO availability. It is of note that simvastatin has already been proven to be clinically effective in two randomized controlled trials. Splanchnic hyperemia can be counteracted by nonselective β-blockers (NSBBs), vasopressin analogs and somatostatin analogs, drugs that until recently were the only available treatments for portal hypertension, but that are not very effective in the initial stages of cirrhosis. There is experimental and clinical evidence indicating that a more effective reduction of portal pressure is obtained by combining agents acting on these different pathways. It is likely that the treatment of portal hypertension will evolve to use etiological treatments together with antifibrotic agents and/or drugs improving sinusoidal endothelial function in the initial stages of cirrhosis (preprimary prophylaxis), while NSBBs will be added in advanced stages of the disease.

  7. Chronic sympathetic activation promotes downregulation of ß-adrenoceptor-mediated effects in the guinea pig heart independently of structural remodeling and systolic dysfunction

    DEFF Research Database (Denmark)

    Soltysinska, Ewa; Thiele, Stefanie; Osadchiy, Oleg;

    2011-01-01

    pathway upon chronic infusion of isoproterenol, a ß-adrenoceptor agonist, at a dose producing no structural left ventricular (LV) remodeling and systolic dysfunction. Subcutaneous isoproterenol infusion (400 µg kg(-1) h(-1) over 16 days) to guinea pigs using osmotic minipumps produced no change in cardiac...... weights, LV internal dimensions, myocyte cross-sectional area, extent of interstitial fibrosis, and basal contractile function. Isolated, perfused heart preparations from isoproterenol-treated guinea pigs exhibited attenuated responsiveness to acute ß-adrenoceptor stimulation, as evidenced by reduced LV...

  8. Ventricular fibrillation induced by a radiofrequency energy delivery for idiopathic premature ventricular contractions arising from the left ventricular anterior papillary muscle.

    Science.gov (United States)

    Yamada, Takumi; McElderry, H Thomas; Allred, James D; Doppalapudi, Harish; Kay, G Neal

    2009-08-01

    A 73-year-old man with idiopathic premature ventricular contractions (PVCs) underwent electrophysiological testing. Left ventricular activation mapping revealed a focal mechanism of the PVCs with the earliest activation on the anterior papillary muscle (APM). Irrigated radiofrequency (RF) current delivered at that site induced a cluster of non-sustained ventricular tachycardia episodes with the same QRS morphology as the PVCs, followed by ventricular fibrillation (VF). The APM might have served as an abnormal automatic trigger and driver for the VF occurrence. Ventricular fibrillation may occur as a complication during RF catheter ablation of papillary muscle ventricular arrhythmias even if the clinical arrhythmia is limited to PVCs.

  9. Autoregulation of coronary blood flow in the isolated beating pig heart.

    Science.gov (United States)

    Schampaert, Stéphanie; van 't Veer, Marcel; Rutten, Marcel C M; van Tuijl, Sjoerd; de Hart, Jurgen; van de Vosse, Frans N; Pijls, Nico H J

    2013-08-01

    The isolated beating pig heart model is an accessible platform to investigate the coronary circulation in its truly morphological and physiological state, whereas its use is beneficial from a time, cost, and ethical perspective. However, whether the coronary autoregulation is still intact is not known. Here, we study the autoregulation of coronary blood flow in the working isolated pig heart in response to brief occlusions of the coronary artery, to step-wise changes in left ventricular loading conditions and contractile states, and to pharmacologic vasodilating stimuli. Six slaughterhouse pig hearts (473 ± 40 g) were isolated, prepared, and connected to an external circulatory system. Through coronary reperfusion and controlled cardiac loading, physiological cardiac performance was achieved. After release of a coronary occlusion, coronary blood flow rose rapidly to an equal (maximum) level as the flow during control beats, independent of the duration of occlusion. Moreover, a linear relation was found between coronary blood flow and coronary driving pressure for a wide variation of preload, afterload, and contractility. In addition, intracoronary administration of papaverine did not yield a transient increase in blood flow indicating the presence of maximum coronary hyperemia. Together, this indicates that the coronary circulation in the isolated beating pig heart is in a permanent state of maximum hyperemia. This makes the model excellently suitable for testing and validating cardiovascular devices (i.e., heart valves, stent grafts, and ventricular assist devices) under well-controlled circumstances, whereas it decreases the necessity of sacrificing large mammalians for performing classical animal experiments. © 2013, Copyright the Authors. Artificial Organs © 2013 Wiley Periodicals, Inc. and International Center for Artificial Organs and Transplantation.

  10. Reactions of pigs to a hot environment

    NARCIS (Netherlands)

    Huynh Thi Thanh Thuy,; Aarnink, A.J.A.; Verstegen, M.W.A.

    2005-01-01

    When compared to other species of farm animals, pigs are relatively sensitive to high environmental temperatures because the pig cannot sweat and is relatively poor at panting. Little information is available about the ambient temperatures above which group-housed pigs start to adapt their mechanism

  11. Fermentation of liquid diets for pigs

    NARCIS (Netherlands)

    Scholten, R.

    2001-01-01

    In the last 30 years major changes occurred in pig nutrition. With the increasing size of the pig farms, manual feeding was replaced by automatic feeding systems. Most pigs were fed on dry diets, but during last the 15 years a clear tendency towards liquid feeding systems was observed. In the early

  12. Weaning the pig - Concepts and consequences

    NARCIS (Netherlands)

    Pluske, J.R.; Dividich, Le J.; Verstegen, M.W.A.

    2003-01-01

    Weaning the Pig: Concepts and Consequences addresses the major issues surrounding the weaning process, both for piglets and the breeding herd, in modern-day pig production. The post-weaned pig presents many challenges to the manager, stockperson and nutritionist, and as such is a critical phase in t

  13. Respiratory health effects in pig farmers.

    NARCIS (Netherlands)

    Preller, L.

    1995-01-01

    This thesis describes a cross-sectional study of risk factors of chronic respiratory health effects in pig farmers working in the South of the Netherlands. The study population comprised 100 pig farmers with and 100 pig farmers without chronic respiratory symptoms. Base-line lung function, non-speci

  14. Weaning the pig - Concepts and consequences

    NARCIS (Netherlands)

    Pluske, J.R.; Dividich, Le J.; Verstegen, M.W.A.

    2003-01-01

    Weaning the Pig: Concepts and Consequences addresses the major issues surrounding the weaning process, both for piglets and the breeding herd, in modern-day pig production. The post-weaned pig presents many challenges to the manager, stockperson and nutritionist, and as such is a critical phase in t

  15. Weaning the pig - Concepts and consequences

    NARCIS (Netherlands)

    Pluske, J.R.; Dividich, Le J.; Verstegen, M.W.A.

    2003-01-01

    Weaning the Pig: Concepts and Consequences addresses the major issues surrounding the weaning process, both for piglets and the breeding herd, in modern-day pig production. The post-weaned pig presents many challenges to the manager, stockperson and nutritionist, and as such is a critical phase in

  16. Acute left ventricular dysfunction secondary to right ventricular septal pacing in a woman with initial preserved contractility: a case report

    Directory of Open Access Journals (Sweden)

    Gribaa Rim

    2011-10-01

    Full Text Available Abstract Introduction Right ventricular apical pacing-related heart failure is reported in some patients after long-term pacing. The exact mechanism is not yet clear but may be related to left ventricular dyssynchrony induced by right ventricular apical pacing. Right ventricular septal pacing is thought to deteriorate left ventricular function less frequently because of a more normal left ventricular activation pattern. Case presentation We report the case of a 55-year-old Tunisian woman with preserved ventricular function, implanted with a dual-chamber pacemaker for complete atrioventricular block. Right ventricular septal pacing induced a major ventricular dyssynchrony, severe left ventricular ejection fraction deterioration and symptoms of congestive heart failure. Upgrading to a biventricular device was associated with a decrease in the symptoms and the ventricular dyssynchrony, and an increase of left ventricular ejection fraction. Conclusion Right ventricular septal pacing can induce reversible left ventricular dysfunction and heart failure secondary to left ventricular dyssynchrony. This complication remains an unpredictable complication of right ventricular septal pacing.

  17. Mechanism for Muscarinic Inhibitory Regulation of the L-type Ca2 + Current in Cardiac Ventricular Myocytes

    Institute of Scientific and Technical Information of China (English)

    蒋彬; 杨向军; 惠杰; 蒋廷波; 宋建平; 刘志华

    2004-01-01

    @@ Objective The autonomic nervous system plays a key role in regulating cardiac function by modifying heart rate, contractility and impulse. The parasympathetic neurotransmitter acetyl-choline and muscarinic agonist carbachol (Cch) inhibit excitation-contraction coupling in cardiac ventricular myocytes. Muscarinic agonists suppress adenylyl cyclase (AC) acitivity and,by reducing activation of the cAMP/protein kinase A (PKA)cascade, inhibit the L-type Ca2+ current (ICa(L) ). They also increase the content of cGMP by stimulating guanylyl cyclase (GC) activity. The role of nitric oxide (NO)/cGMP in muscarinic inhibition has undergone considerable scrutiny. The role of the NO/cGMP pathway in the inhibition of ICa(L) by Cch was examined in guinea-pig ventricular myocytes.

  18. Effects of extracellular potassium on ventricular automaticity and evidence for a pacemaker current in mammalian ventricular myocardium.

    Science.gov (United States)

    Katzung, B G; Morgenstern, J A

    1977-01-01

    Automaticity was induced in isolated guinea pig and cat papillary muscles by application of depolarizing constant current pulses. Increasing extracellular potassium from 1 to 15 mM caused a shift of pacemaker-like activity to less negative diastolic potentials and a decrease in maximum phase 4 slope. Membrane resistance, estimated from the relation of applied current to maximum diastolic potential, decreased when extracellular potassium was increased. Voltage clamps of cat papillary muscle demonstrated that action potentials activate a time-dependent outward current which has a reversal potential of -79.1 mV (+/- 0.99 SE, n = 20) at an extracellular potassium concentration of 5 mM. The reversal potential of this current varies with extracellular K+ with a slope of 50-60 mV per 10-fold concentration change. The current is activated by voltage clamps or action potential plateaus in the range of -30 to +30 mV. It has a time constant of deactivation which increases from approximately 100 to over 400 msec as clamp potential is increased from -90 to -60 mV. It is proposed that this current is equivalent to Ix1 demonstrated in other cardiac tissues and is responsible, in combination with inward currents, for automaticity in ventricular fibers.

  19. Comparative analyses of QTLs influencing obesity and metabolic phenotypes in pigs and humans

    DEFF Research Database (Denmark)

    Pant, Sameer Dinkar; Karlskov-Mortensen, Peter; Jacobsen, Mette Juul

    2015-01-01

    in different populations. Several important genes previously associated to obesity in human studies, along with novel genes were identified. Altogether, this study provides novel insight that may further the current understanding of the molecular mechanisms underlying human obesity.......The pig is a well-known animal model used to investigate genetic and mechanistic aspects of human disease biology. They are particularly useful in the context of obesity and metabolic diseases because other widely used models (e.g. mice) do not completely recapitulate key pathophysiological...... features associated with these diseases in humans. Therefore, we established a F2 pig resource population (n = 564) designed to elucidate the genetics underlying obesity and metabolic phenotypes. Segregation of obesity traits was ensured by using breeds highly divergent with respect to obesity traits...

  20. How to protect the heart in septic shock: a hypothesis on the pathophysiology and treatment of septic heart failure.

    Science.gov (United States)

    Schmittinger, Christian A; Wurzinger, Bettina; Deutinger, Martina; Wohlmuth, Christoph; Knotzer, Hans; Torgersen, Christian; Dünser, Martin W; Hasibeder, Walter R

    2010-03-01

    Heart failure is a well-recognized manifestation of organ failure in sepsis and septic shock. The pathophysiology of septic heart failure is complex and currently believed to involve several mechanisms. So far, the contributory role of high plasma catecholamine levels has not been investigated. In this manuscript, we present a hypothesis suggesting that excessive catecholamine production and exogenous administration of catecholamines may relevantly contribute to the development of heart failure and cardiovascular collapse in patients suffering from septic shock. Substantially elevated plasma catecholamine levels were measured during critical illness and sepsis or septic shock. There is a growing body of clinical and experimental evidence demonstrating that high catecholamine plasma levels exert direct toxic effects on the heart. The pathophysiologic mechanisms involved in catecholamine-induced cardiomyocyte toxicity may involve a combination of inflammation, oxidative stress, and abnormal calcium handling resulting in myocardial stunning, apoptosis and necrosis. Clinical signs of catecholamine-induced heart failure can present with a wide range of symptoms reaching from subtle histological changes with preserved myocardial pump function to severe heart failure exhibiting a distinctive echocardiographic pattern which became known as "Takotsubo"-like cardiomyopathy or the left ventricular apical ballooning syndrome. In a medical intensive care unit patient population, presence of sepsis was the only variable associated with the development of left ventricular apical ballooning. Since several therapeutic interventions influence catecholamine plasma levels in septic shock patients, treatment strategies aiming at the reduction of endogenous or exogenous catecholamine exposure may protect the heart during septic shock and could facilitate patient survival.

  1. Premature Ventricular Complexes and Premature Ventricular Complex Induced Cardiomyopathy.

    Science.gov (United States)

    Latchamsetty, Rakesh; Bogun, Frank

    2015-09-01

    Presentation, prognosis, and management of premature ventricular complexes (PVCs) vary significantly among patients and depend on PVC characteristics as well as patient comorbidities. Presentation can range from incidental discovery in an asymptomatic patient to debilitating heart failure. Prognosis depends on, among other factors, the presence or absence of structural heart disease, PVC burden and other factors detailed in this review. Our understanding of the clinical significance of frequent PVCs, particularly as it relates to development of cardiomyopathy, has advanced greatly in the past decade. In this article, we explore the mechanisms governing PVC initiation and discuss prevalence and frequency of PVCs in the general population. We also explore prognostic implications based on PVC frequency as well as the presence or absence of underlying heart disease. We then take a focused look at PVC-induced cardiomyopathy and identify predictors for developing cardiomyopathy. Finally, we discuss clinical evaluation and management of patients presenting with frequent PVCs. Management can include clinical observation, addressing reversible causes, lifestyle modification, pharmacotherapy, or catheter ablation.

  2. 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.

  3. 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.

  4. Cardiac sarcoidosis mimicking right ventricular dysplasia.

    Science.gov (United States)

    Shiraishi, Jun; Tatsumi, Tetsuya; Shimoo, Kazutoshi; Katsume, Asako; Mani, Hiroki; Kobara, Miyuki; Shirayama, Takeshi; Azuma, Akihiro; Nakagawa, Masao

    2003-02-01

    A 59-year-old woman with skin sarcoidosis was admitted to hospital for assessment of complete atrioventricular block. Cross-sectional echocardiography showed that the apical free wall of the right ventricle was thin and dyskinetic with dilation of the right ventricle. Thallium-201 myocardial imaging revealed a normal distribution. Both gallium-67 and technetium-99m pyrophosphate scintigraphy revealed no abnormal uptake in the myocardium. Right ventriculography showed chamber dilation and dyskinesis of the apical free wall, whereas left ventriculography showed normokinesis, mimicking right ventricular dysplasia. Cardiac sarcoidosis was diagnosed on examination of an endomyocardial biopsy specimen from the right ventricle. A permanent pacemaker was implanted to manage the complete atrioventricular block. After steroid treatment, electrocardiography showed first-degree atrioventricular block and echocardiography revealed an improvement in the right ventricular chamber dilation. Reports of cardiac sarcoidosis mimicking right ventricular dysplasia are extremely rare and as this case shows, right ventricular involvement may be one of its manifestations.

  5. Enteric Methane Emission from Pigs

    DEFF Research Database (Denmark)

    Jørgensen, Henry; Theil, Peter Kappel; Knudsen, Knud Erik Bach

    2011-01-01

    The modern pig industry rely on relatively few feedstuffs mostly from cereals (corn, wheat, barley, oats, rye and rice), cereal co-products (different milling fractions, residues from biofuel and alcohol industries, etc.), cereal substitutes (tapioca, maniocca), legumes (peas, beans, lupins......), protein concentrates (meal or cakes of soybean, rape, sunflower, cotton) and co-products from the sugar and starch industries to produce compounds feeds. The classical pig diet can also be characterised as relatively concentrated but an increased demand of high energy cereals for direct human use...... and increased availability of fibre rich ingredients from, for instance, the feed milling or starch extraction/fermentation industries have promoted an increased utilisation of fibre rich co-products in the pig feeds (Serena et al. 2007). Especially pregnant sows may be supplied with fibre rich diets without...

  6. Pig Brain Mitochondria as a Biological Model for Study of Mitochondrial Respiration.

    Science.gov (United States)

    Fišar, Z; Hroudová, J

    2016-01-01

    Oxidative phosphorylation is a key process of intracellular energy transfer by which mitochondria produce ATP. Isolated mitochondria serve as a biological model for understanding the mitochondrial respiration control, effects of various biologically active substances, and pathophysiology of mitochondrial diseases. The aim of our study was to evaluate pig brain mitochondria as a proper biological model for investigation of activity of the mitochondrial electron transport chain. Oxygen consumption rates of isolated pig brain mitochondria were measured using high-resolution respirometry. Mitochondrial respiration of crude mitochondrial fraction, mitochondria purified in sucrose gradient, and mitochondria purified in Percoll gradient were assayed as a function of storage time. Oxygen flux and various mitochondrial respiratory control ratios were not changed within two days of mitochondria storage on ice. Leak respiration was found higher and Complex I-linked respiration lower in purified mitochondria compared to the crude mitochondrial fraction. Damage to both outer and inner mitochondrial membrane caused by the isolation procedure was the greatest after purification in a sucrose gradient. We confirmed that pig brain mitochondria can serve as a biological model for investigation of mitochondrial respiration. The advantage of this biological model is the stability of respiratory parameters for more than 48 h and the possibility to isolate large amounts of mitochondria from specific brain areas without the need to kill laboratory animals. We suggest the use of high-resolution respirometry of pig brain mitochondria for research of the neuroprotective effects and/or mitochondrial toxicity of new medical drugs.

  7. A case with catecholaminergic polymorphic ventricular tachycardia

    Directory of Open Access Journals (Sweden)

    Ahmet Ünalır

    2011-06-01

    Full Text Available Catecholaminergic polymorphic ventricular tachycardia (CPVT is a rare type of polymorphic ventricular tachycardias in individuals without structural cardiac abnormalities. It typically has been induced by exercise or emotional stres. It generally is seen in childhood and adolescent period but rarely is seen in elderly. It usually ends by spontaneus, but rarely cause hemodynamic collapse. In here, we present a case with CPVT of successful treatment with a beta blocker therapy. J Clin Exp Invest 2011;2(2:232-4

  8. Case series: Congenital left ventricular diverticulum

    Directory of Open Access Journals (Sweden)

    Shah Dharita

    2010-01-01

    Full Text Available Congenital left ventricular diverticulum is a rare cardiac malformation characterized by a localized outpouching from the cardiac chamber. The patient is usually asymptomatic. However, complications like embolism, infective endocarditis, arrhythmia and, rarely, rupture can be the initial presentation. Diagnosis can be established by USG, echocardiography, CT angiography, and MRI. We report here two neonates with congenital left ventricular apical diverticulum associated with epigastric hernia.

  9. 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-susta......-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....

  10. Ventricular Septal Defect from Takotsubo Syndrome

    Science.gov (United States)

    Caplow, Julie; Quatromoni, Neha

    2016-01-01

    Takotsubo Syndrome is a transient condition characterized by left ventricular systolic dysfunction with apical akinesis/dyskinesis and ballooning. Although the prognosis with medical management is excellent in most cases, rare cases of serious complications can occur. We present here a case of a 71-year-old woman presenting with acute decompensated heart failure with initial findings consistent with a myocardial infarction, who was found instead to have an acute ventricular septal defect as a complication of Takotsubo Syndrome. PMID:27563471

  11. Ventricular Septal Defect from Takotsubo Syndrome

    Directory of Open Access Journals (Sweden)

    Daniel Y. Lu

    2016-01-01

    Full Text Available Takotsubo Syndrome is a transient condition characterized by left ventricular systolic dysfunction with apical akinesis/dyskinesis and ballooning. Although the prognosis with medical management is excellent in most cases, rare cases of serious complications can occur. We present here a case of a 71-year-old woman presenting with acute decompensated heart failure with initial findings consistent with a myocardial infarction, who was found instead to have an acute ventricular septal defect as a complication of Takotsubo Syndrome.

  12. Right ventricular mass estimation by angioechocardiography.

    Science.gov (United States)

    Arcilla, R A; Mathew, R; Sodt, P; Lester, L; Cahill, N; Thilenius, O G

    1976-01-01

    A combined angiocardiographic-echocardiographic method for estimating right ventricular wall mass is described. Biplane cineangiocardiograms are analyzed for ventricular volume in end-diastole, and wall thickness is determined from echocardiograms obtained with a high frequency transducer and strip chart recorder, The intracavitary and the external surface volumes of the ventricle are derived, and the difference multiplied by 1.050, the specific gravity of myocardium. Excellent correlation was observed between right ventricular wall mass and body surface area in normal children (r = 0.93). The mean right ventricular mass was 44.5 g/M2 as compared to 78.1 g/M2 for the left ventricle, corresponding mass/EDV values were 0.48 g/cm3 and 1.26 g/cm3, respectively. In isolated right ventricular pressure overload, the increase in right ventricular mass is chiefly due to the increase in wall thickness; in volume overload, it is due mostly to the increase in chamber volume,

  13. Selective left ventricular sensing lead implantation to overcome undersensing of ventricular fibrillation during implantable cardioverter defibrillator implantation.

    Science.gov (United States)

    Steinberg, Christian; Philippon, François; O'Hara, Gilles; Molin, Franck

    2013-06-01

    Accurate sensing of malignant arrhythmia is critical for the appropriate delivery of therapy from implantable cardioverter defibrillators, and undersensing of ventricular tachyarrhythmias can have catastrophic consequences. Here, we present an unusual case of ventricular fibrillation undersensing from the right ventricular lead at multiple different implantation sites because of very low amplitude voltage signals during induced ventricular fibrillation. A left ventricular sensing electrode was implanted to allow correct sensing and therapy delivery.

  14. Pulmonary Hypertension in Heart Failure: Pathophysiology, Pathobiology, and Emerging Clinical Perspectives.

    Science.gov (United States)

    Guazzi, Marco; Naeije, Robert

    2017-04-04

    Pulmonary hypertension is a common hemodynamic complication of heart failure. Interest in left-sided pulmonary hypertension has increased remarkably in recent years because its development and consequences for the right heart are now seen as mainstay abnormalities that begin in the early stages of the disease and bear unfavorable prognostic insights. However, some knowledge gaps limit our ability to influence this complex condition. Accordingly, attention is now focused on: 1) establishing a definitive consensus for a hemodynamic definition, perhaps incorporating exercise and fluid challenge; 2) implementing the limited data available on the pathobiology of lung capillaries and small arteries; 3) developing standard methods for assessing right ventricular function and, hopefully, its coupling to pulmonary circulation; and 4) searching for effective therapies that may benefit lung vessels and the remodeled right ventricle. The authors review the pathophysiology, pathobiology, and emerging clinical perspectives on pulmonary hypertension across the broad spectrum of heart failure stages. Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  15. Takotsubo cardiomyopathy systematic review: Pathophysiologic process, clinical presentation and diagnostic approach to Takotsubo cardiomyopathy.

    Science.gov (United States)

    Ono, Ryohei; Falcão, L Menezes

    2016-04-15

    Takotsubo cardiomyopathy (TTC) is characterized by transient left ventricular apical ballooning with the absence of coronary occlusion, which typically occurs in older women after emotional or physical stress. The pathophysiology of TTC is not well established, though several possible causes such as catecholamine cardiotoxicity, metabolic disturbance, coronary microvascular impairment and multivessel epicardial coronary artery spasm have been proposed. A number of diagnostic criteria have been suggested in the world and not unified as single, but the most common accepted one is Mayo Clinic proposed criteria. Since the clinical presentation of TTC is usually similar to acute coronary syndrome, differential diagnosis is essential to exclude other diseases and also for its treatment. Imaging modality including echocardiogram, angio CT and cardiac MRI, and lab tests for catecholamine, troponin T, creatine kinase MB and B-type natriuretic peptide can be useful to differentiate TTC from other diseases. Prognosis is generally favorable and in-hospital mortality is from 0% to within 10%. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  16. The emerging roles of leptin and ghrelin in cardiovascular physiology and pathophysiology.

    Science.gov (United States)

    Sharma, Vijay; McNeill, John H

    2005-04-01

    Leptin and ghrelin are novel peptide hormones which are counter-regulatory in the central control of appetite. More recently, it has become clear that these hormones have a range of effects on the cardiovascular system. Leptin increases sympathetic activity, producing a pressor effect when acting on the central nervous system. However, leptin produces vasodilation by an endothelium-dependent mechanism peripherally. Ghrelin decreases sympathetic activity and has a depressor effect when acting on the central nervous system. Peripherally, ghrelin produces vasodilation by an endothelium-independent mechanism. Ghrelin improves left ventricular function and cardiac cachexia in heart failure. Leptin may contribute to cardiac cachexia, and to obesity-related cardiomyopathy by a variety of mechanisms. Leptin has pro-inflammatory, proliferative and calcification promoting effects in the vasculature. Ghrelin has recently been shown to be anti-inflammatory in the vasculature. Leptin may also produce a pro-thrombotic state through stimulation of platelet aggregation and inhibition of coagulation and fibrinolysis. The evidence for and against these effects as well as their pathophysiological significance in obesity hypertension, heart failure, atherosclerosis and thrombosis are discussed.

  17. Reduced sodium current in the lateral ventricular wall induces inferolateral J-waves

    Directory of Open Access Journals (Sweden)

    Veronique Marlinde Frederica Meijborg

    2016-08-01

    Full Text Available Background: 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. Methods: 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.Results: 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.Conclusion: Reduced sodium current in the left lateral ventricular myocardium can cause inferolateral J-waves on the ECG.

  18. Fermentation of liquid diets for pigs

    OpenAIRE

    Scholten, R.

    2001-01-01

    In the last 30 years major changes occurred in pig nutrition. With the increasing size of the pig farms, manual feeding was replaced by automatic feeding systems. Most pigs were fed on dry diets, but during last the 15 years a clear tendency towards liquid feeding systems was observed. In the early 80's the use of liquid co-products from the human food industry was introduced into pig nutrition. In the Netherlands, nowadays about 20% of the slaughter pigs and about 10% of the sows is fed a li...

  19. Effects of right atrial and ventricular DDD pacing on cardiac function and ventricular contraction synchrony

    Institute of Scientific and Technical Information of China (English)

    支力大; 华伟; 张澍; 史蓉芳; 王方正; 陈新

    2004-01-01

    Background Right ventricular apical pacing has been reported to reduce cardiac performance. But there are few reports on the effects of dual chamber (DDD) pacing on cardiac function compared to sinus rhythm. In this study, we evaluated the effects of right atrial and ventricular DDD pacing on cardiac function and ventricular contraction synchrony using equilibrium radionuclide angiography.Methods Ten patients implanted with a right atrial and ventricular DDD pacemaker underwent equilibrium radionuclide angiography. The scintigraphic data were obtained during sinus rhythm and pacing rhythm. Cardiac function parameters were obtained semimanually. Phase analysis was used to study the ventricular activation sequence and ventricular synchrony.Results The left ventricular 1/3 ejection fraction decreased significantly during pacing compared with that during sinus rhythm[(23.4 ±6.1)% vs(27.7 ±4.5)%, P =0.01]. Regional ejection fraction also decreased during pacing, although the difference was not statistically significant. Phase analysis showed that the right ventricle was activated earlier than the left ventricle during pacing, and that the phase shift was significantly greater during pacing than that during sinus rhythm[64.13°±16.80° vs 52.88°± 9.26°, P =0.007]. The activation of both ventricles occurred simultaneously during sinus rhythm, with the activation sequence from proximal septum or base of left ventricle to apex. The earliest activation during pacing occurred at the right ventricular apex, and subsequently spread to the base and left ventricle.Conclusion Right atrial and ventricular DDD pacing impairs left ventricular systolic function and ventricular synchrony.

  20. SPARQling Pig - Processing Linked data with Pig Latin

    DEFF Research Database (Denmark)

    Hagedorn, Stefan; Hose, Katja; Sattler, Kai-Uwe

    2015-01-01

    -defined functions while running on top of scalable distributed platforms. In doing so, these languages enable analytical tasks while avoiding the limitations of classical query languages such as SQL and SPARQL. However, the tuple-oriented view of general-purpose languages like Pig does not match very well...

  1. Electrohydraulic ventricular assist device development.

    Science.gov (United States)

    Diegel, P D; Mussivand, T; Holfert, J W; Juretich, J T; Miller, J A; Maclean, G K; Szurmak, Z; Santerre, J P; Rajagopalan, K; Dew, P A

    1992-01-01

    An electrohydraulic ventricular assist device has been developed. An axial flow pump driven by a brushless DC motor provides actuation. Energy is supplied by internal Ni/Cd batteries and by external Ag/Zn batteries, both rechargeable. Electromagnetic induction is used to pass energy through the skin with a transcutaneous energy transfer (TET) system. Physiologic control, battery management, motor commutation, and communication functions are performed by a surface mount internal controller. An infrared data link within the TET coils provides bidirectional communication between the external and internal controllers. A computer model was developed to predict system performance. The dimensions are 180 mm x 116 mm x 40 mm. An in vitro system pumped 5.7 L/min at 10 mmHg inflow and 100 mmHg outflow pressure. The internal battery can provide the projected energy requirements for 40 min after 540 charge/discharge cycles, and the external battery is capable of 4 hr of operation after 150 cycles. The TET system can deliver 60 W of power and exceeds 80% efficiency between 15 and 30 W. The device configuration is based on human cadaver and intraoperative fit trials. The device is being modified for calf implantation by redirecting the blood ports, increasing the output, and incorporating the internal controller in the unified device base.

  2. Requirements for the formal representation of pathophysiology mechanisms by clinicians.

    Science.gov (United States)

    de Bono, B; Helvensteijn, M; Kokash, N; Martorelli, I; Sarwar, D; Islam, S; Grenon, P; Hunter, P

    2016-04-01

    Knowledge of multiscale mechanisms in pathophysiology is the bedrock of clinical practice. If quantitative methods, predicting patient-specific behaviour of these pathophysiology mechanisms, are to be brought to bear on clinical decision-making, the Human Physiome community and Clinical community must share a common computational blueprint for pathophysiology mechanisms. A number of obstacles stand in the way of this sharing-not least the technical and operational challenges that must be overcome to ensure that (i) the explicit biological meanings of the Physiome's quantitative methods to represent mechanisms are open to articulation, verification and study by clinicians, and that (ii) clinicians are given the tools and training to explicitly express disease manifestations in direct contribution to modelling. To this end, the Physiome and Clinical communities must co-develop a common computational toolkit, based on this blueprint, to bridge the representation of knowledge of pathophysiology mechanisms (a) that is implicitly depicted in electronic health records and the literature, with (b) that found in mathematical models explicitly describing mechanisms. In particular, this paper makes use of a step-wise description of a specific disease mechanism as a means to elicit the requirements of representing pathophysiological meaning explicitly. The computational blueprint developed from these requirements addresses the Clinical community goals to (i) organize and manage healthcare resources in terms of relevant disease-related knowledge of mechanisms and (ii) train the next generation of physicians in the application of quantitative methods relevant to their research and practice.

  3. Preliminary Measurement of Internal Organs of Congjiang Fragrance Pig and Huanjiang Fragrance Pig

    Institute of Scientific and Technical Information of China (English)

    Shen; Xuelin; Duan; Yongbang; Zhang; Yi; Liu; Peiqiong

    2014-01-01

    Fragrance pig is a famous miniature local breed in China,which is similar to human on the aspects of physical structure,anatomy,nutrition,metabolism and blood biochemical indicators. The internal organs of Congjiang fragrance pig and Huanjiang fragrance pig with different month ages were weighed. The results showed that the proportion of stomach in body weight in Congjiang fragrance pig was higher than that in Min pig,Harbin white and Landrace,and the proportion of large intestine in body weight in Congjiang fragrance pig was also higher than that in ordinary pigs; the weights of heart,liver and kidney in 8- 10 months old Congjiang fragrance pig were similar to that in Chinese adults. This provided reference data for future in-depth development and utilization of fragrance pig.

  4. Arrhythmogenic right ventricular cardiomyopathy/dysplasia

    Directory of Open Access Journals (Sweden)

    Basso Cristina

    2007-11-01

    Full Text Available Abstract Arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D is a heart muscle disease clinically characterized by life-threatening ventricular arrhythmias. Its prevalence has been estimated to vary from 1:2,500 to 1:5,000. ARVC/D is a major cause of sudden death in the young and athletes. The pathology consists of a genetically determined dystrophy of the right ventricular myocardium with fibro-fatty replacement to such an extent that it leads to right ventricular aneurysms. The clinical picture may include: a subclinical phase without symptoms and with ventricular fibrillation being the first presentation; an electrical disorder with palpitations and syncope, due to tachyarrhythmias of right ventricular origin; right ventricular or biventricular pump failure, so severe as to require transplantation. The causative genes encode proteins of mechanical cell junctions (plakoglobin, plakophilin, desmoglein, desmocollin, desmoplakin and account for intercalated disk remodeling. Familiar occurrence with an autosomal dominant pattern of inheritance and variable penetrance has been proven. Recessive variants associated with palmoplantar keratoderma and woolly hair have been also reported. Clinical diagnosis may be achieved by demonstrating functional and structural alterations of the right ventricle, depolarization and repolarization abnormalities, arrhythmias with the left bundle branch block morphology and fibro-fatty replacement through endomyocardial biopsy. Two dimensional echo, angiography and magnetic resonance are the imaging tools for visualizing structural-functional abnormalities. Electroanatomic mapping is able to detect areas of low voltage corresponding to myocardial atrophy with fibro-fatty replacement. The main differential diagnoses are idiopathic right ventricular outflow tract tachycardia, myocarditis, dialted cardiomyopathy and sarcoidosis. Only palliative therapy is available and consists of antiarrhythmic drugs

  5. Effect of right ventricular pacing on ventricular rhythm during atrial fibrillation

    NARCIS (Netherlands)

    Wittkampf, F.H.M.; Jongste, M.J.L. de; Lie, H.I.; Meijler, F.L.

    1988-01-01

    In 13 patients with atrial fibrillation, the effect of right ventricular pacing at various rates on spontaneous RR intervals was studied. Five hundred consecutive RR intervals were recorded and measured before and during varying right ventricular pacing rates. As anticipated, all RR intervals longer

  6. Radiofrequency ablation therapy of intractable ventricular tachycardia present with a left ventricular assist device

    DEFF Research Database (Denmark)

    Nielsen, Jan Møller; Kristiansen, Steen Buus; Gerdes, Christian;

    2015-01-01

    Ventricular tachycardia (VT) occurs in up to 59% of patients with left ventricular assist devices (LVAD). In some of these patients, the VT cannot be managed medically or by implantable cardioverter-defibrillator. In this case, a 66-year-old male was successfully treated with radiofrequency...

  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. Outpatient evaluation and management of patients with ventricular premature beats or non-sustained ventricular tachycardia

    DEFF Research Database (Denmark)

    Svendsen, Jesper Hastrup; Goette, Andreas; Dobreanu, Dan

    2012-01-01

    In this survey, European physicians who deal with arrhythmia patients gave their opinions about diagnostic work up when they see patients with ventricular premature beats (VPBs) or non-sustained ventricular tachycardia (NSVT). In general, similar work-up regimens were used for these two arrhythmias...

  9. Giant left ventricular fibroma presenting as ventricular tachycardia in a child.

    Science.gov (United States)

    Khan, Muhammad Arif; Saeedi, Abdul Raoof Al; Tayeab, Hyfeah Al; Momenah, Tarek

    2014-06-01

    We present a rare case of giant left ventricular apical fibroma presenting as recurrent ventricular tachycardia in a 14-month-old girl. The diagnosis was made by echocardiography and chest computed tomography, and confirmed by histopathology. The fibroma was resected surgically, and the patient followed up for 4 years.

  10. Fermented liquid feed for pigs.

    Science.gov (United States)

    Missotten, Joris A M; Michiels, Joris; Ovyn, Anneke; De Smet, Stefaan; Dierick, Noël A

    2010-12-01

    Since the announcement of the ban on the use of antibiotics as antimicrobial growth promoters in the feed of pigs in 2006 the investigation towards alternative feed additives has augmented considerably. Although fermented liquid feed is not an additive, but a feeding strategy, the experimental work examining its possible advantages also saw a rise. The use of fermented liquid feed (FLF) has two main advantages, namely that the simultaneous provision of feed and water may result in an alleviation of the transition from the sow milk to solid feed and may also reduce the time spent to find both sources of nutrients, and secondly, that offering FLF with a low pH may strengthen the potential of the stomach as a first line of defence against possible pathogenic infections. Because of these two advantages, FLF is often stated as an ideal feed for weaned piglets. The results obtained so far are rather variable, but in general they show a better body weight gain and worse feed/gain ratio for the piglets. However, for growing-finishing pigs on average a better feed/gain ratio is found compared to pigs fed dry feed. This better performance is mostly associated with less harmful microbiota and better gut morphology. This review provides an overview of the current knowledge of FLF for pigs,dealing with the FLF itself as well as its effect on the gastrointestinal tract and animal performance.

  11. People, Pigs, Pork and Preferences

    DEFF Research Database (Denmark)

    Thorslund, Cecilie Agnete H

    , depending on whether they relate to an everyday or production context. Furthermore, some interesting national differences emerged, pointing at the need for more than one marketing strategy if pig welfare is to be supported through consumer demand. Overall, this thesis contributes with important findings...

  12. People, Pigs, Pork and Preferences

    DEFF Research Database (Denmark)

    Thorslund, Cecilie Agnete H

    , depending on whether they relate to an everyday or production context. Furthermore, some interesting national differences emerged, pointing at the need for more than one marketing strategy if pig welfare is to be supported through consumer demand. Overall, this thesis contributes with important findings...

  13. Improving efficiency in pig production

    African Journals Online (AJOL)

    important. The production of lean meat is shown to be improved significantly by adopting ... is interested in the biology of pig production, then biological efficiency and its .... scientific basis, I have calculated the economic effects of a number of ...

  14. Virtual dissection of pig carcasses

    DEFF Research Database (Denmark)

    Vester-Christensen, Martin; Erbou, Søren Gylling Hemmingsen; Hansen, Mads Fogtmann

    2009-01-01

    This paper proposes the use of computed tomography (CT) as a reference method for estimating the lean meat percentage (LMP) of pig carcasses. The current reference is manual dissection which has a limited accuracy due to variability between butchers. A contextual Bayesian classification scheme...

  15. Incidence, diagnosis and pathophysiology of amniotic fluid embolism.

    Science.gov (United States)

    Ito, F; Akasaka, J; Koike, N; Uekuri, C; Shigemitsu, A; Kobayashi, H

    2014-10-01

    Amniotic fluid embolism (AFE) is a rare clinical entity, sometimes fatal. A review was conducted to describe the frequency, diagnosis and pathophysiology of AFE. The reported incidences ranged from 1.9 cases per 100,000 maternities (UK) to 6.1 per 100,000 maternities (Australia), which can vary considerably, depending on the period, region of study and the definition. Although the development of amniotic fluid-specific markers would have an impact on early diagnosis, definition of AFE based on these markers is not widely accepted. To date, immunological mechanisms, amniotic fluid-dependent anaphylactic reaction and complement activation, have been proposed as potential pathogenetic and pathophysiological mechanisms. Immune cell activation induced through complement activation may be associated with the mechanism that immediately initiates maternal death, only in susceptible individuals. This review will focus on advances in the field of AFE biology and discuss the prevalence, diagnosis and pathophysiology of AFE.

  16. Pathophysiology of reversible sudden deafness--epidemiological study.

    Directory of Open Access Journals (Sweden)

    Ohsaki,Katsuichiro

    1983-04-01

    Full Text Available Many aspects of the etiology and pathophysiology of reversible sudden deafness remain obscure. In order to better understand the pathophysiology of reversible sudden deafness we compared the results of two therapies which have different mechanisms of action. The results of therapy with tranexamic acid alone in 49 cases (57 ears of sudden deafness were compared with the results of treatment with so-called antisludging agents in 65 cases (69 ears using the chi square contingency test. The same therapeutic effect was observed in both groups despite the different modes of chemical action of the two therapeutics. A series of processes involving an increase in permeability of vascular walls and related edema, and extravascular red cell oozing due to hypoxia or anoxia leading to tissue damage in the inner ear seem to be important factors in the etiology and pathophysiology of reversible sudden deafness.

  17. [Pathophysiology of hypertension : What are our current concepts?].

    Science.gov (United States)

    Jordan, J

    2015-03-01

    In the year 2015, many questions regarding the pathophysiology of essential arterial hypertension remain unresolved. Substantial scientific progress has been made in various medical areas aided by novel molecular"omics" techniques. The findings could then be implemented in diagnostic and therapeutic procedures. In the field of hypertension research such methods have been applied in very large cohorts but have contributed less to pathophysiological understanding and clinical management than expected. The findings on the pathophysiological importance of baroreflex mechanisms, natriuretic peptides and osmotically inactive sodium storage discussed in this article all have something in common: all are based on small, carefully conducted human physiological investigations and often challenge current textbook knowledge. Nevertheless, these findings have opened up new research fields and are likely to affect clinical care.

  18. Velopharyngeal sphincter pathophysiologic aspects in the in cleft palat

    Directory of Open Access Journals (Sweden)

    Collares, Marcus Vinicius Martins

    2008-09-01

    Full Text Available Introduction: Cleft lip and palate are common congenital abnormalities with typical functional disorders on speech, deglutition and middle ear function. Objective: This article reviews functional labiopalatine disorders through a pathophysiological view. Method: We performed a literature search on line, as well as books and periodicals related to velopharyngeal sphincter. Our sources were LILACS, MEDLINE and SciELO databases, and we applied to the research Keywords of interest on the velopharyngeal pathophysiology, for articles published between 1965 and 2007. Conclusion: Velopharyngeal sphincter plays a central role in speech, swallowing and middle ear physiology in patients with labiopalatine cleft. At the end of our bibliographic review, pursuant to the velopharyngeal physiology in individuals with this disorder in the functional speech, deglutition and otologic function, we observed that although there is a great number of published data discussing this issue, further studies are necessary to completely understand the pathophysiology, due to the fact they have been exploited superficially.

  19. Postoperative normalization of left ventricular noncompaction and new echocardiographic signs in aorta to left ventricular tunnel.

    Science.gov (United States)

    Malakan Rad, Elaheh; Zeinaloo, Ali Akbar

    2013-04-01

    We report postoperative normalization of left ventricular noncompaction in a neonate undergoing successful neonatal surgery for type II aorta to left ventricular tunnel (ALVT) associated with a large patent ductus arteriosus, floppy and extremely redundant anterior mitral leaflet, right coronary artery arising directly from the tunnel, and severe left ventricular noncompaction. We also described 2 novel echocardiographic findings in ALVT including "triple wavy line sign" on M-mode echocardiography which disappeared 1 month after operation and "abnormally increased left ventricular posterior wall motion" on M-mode of standard parasternal long-axis view on color tissue Doppler imaging (TDI) that also normalized postoperatively. We showed that proper definition of endocardial border is extremely important in strain and strain rate imaging in the context of left ventricular noncompaction. Preoperative longitudinal strain and strain rate were significantly decreased in comparison to radial strain and strain rate. Circumferential strain and strain rate were normal. © 2013, Wiley Periodicals, Inc.

  20. Nonpeptide tachykinin receptor antagonists. III. SB 235375, a low central nervous system-penetrant, potent and selective neurokinin-3 receptor antagonist, inhibits citric acid-induced cough and airways hyper-reactivity in guinea pigs.

    Science.gov (United States)

    Hay, Douglas W P; Giardina, Giuseppe A M; Griswold, Don E; Underwood, David C; Kotzer, Charles J; Bush, Brian; Potts, William; Sandhu, Punam; Lundberg, Dave; Foley, James J; Schmidt, Dulcie B; Martin, Lenox D; Kilian, David; Legos, Jeffrey J; Barone, Frank C; Luttmann, Mark A; Grugni, Mario; Raveglia, Luca F; Sarau, Henry M

    2002-01-01

    In this report the in vitro and in vivo pharmacological and pharmacokinetic profile of (-)-(S)-N-(alpha-ethylbenzyl)-3-(carboxymethoxy)-2-phenylquinoline-4-carboxamide (SB 235375), a low central nervous system (CNS)-penetrant, human neurokinin-3 (NK-3) receptor (hNK-3R) antagonist, is described. SB 235375 inhibited (125)I-[MePhe(7)]-neurokinin B (NKB) binding to membranes of Chinese hamster ovary (CHO) cells expressing the hNK-3R (CHO-hNK-3R) with a K(i) = 2.2 nM and antagonized competitively NKB-induced Ca(2+) mobilization in human embryonic kidney (HEK) 293 cells expressing the hNK-3R (HEK 293-hNK-3R) with a K(b) = 12 nM. SB 235375 antagonized senktide (NK-3R)-induced contractions in rabbit isolated iris sphincter (pA(2) = 8.1) and guinea pig ileal circular smooth muscles (pA(2) = 8.3). SB 235375 was selective for the hNK-3R compared with hNK-1 (K(i) > 100,000 nM) and hNK-2 receptors (K(i) = 209 nM), and was without effect, at 1 microM, in 68 other receptor, enzyme, and ion channel assays. Intravenous SB 235375 produced a dose-related inhibition of miosis induced by i.v. senktide in the rabbit (ED(50) of 0.56 mg/kg). Intraperitoneal SB 235375 (10-30 mg/kg) inhibited citric acid-induced cough and airways hyper-reactivity in guinea pigs. In mice oral SB 235375 (3-30 mg/kg) was without significant effect on the behavioral responses induced by intracerebral ventricular administration of senktide. Pharmacokinetic evaluation in the mouse and rat revealed that oral SB 235375 was well absorbed systemically but did not effectively cross the blood-brain barrier. The preclinical profile of SB 235375, encompassing high affinity, selectivity, oral activity, and low CNS penetration, suggests that it is an appropriate tool compound to define the pathophysiological roles of the NK-3Rs in the peripheral nervous system.

  1. Bloqueo aurículo-ventricular de primer grado en tirotoxicosis aguda First degree atrio-ventricular block in acute thyrotoxicosis

    Directory of Open Access Journals (Sweden)

    Antonio R. Vilches

    2004-02-01

    Full Text Available El cuadro clínico de la tirotoxicosis incluye síntomas cardiovasculares variados. La taquicardia sinusal es el trastorno electrocardiográfico más frecuente y los trastornos de conducción son extremadamente raros como modo de presentación. Comunicamos un caso de bloqueo aurículo-ventricular de primer grado en una paciente con hipertiroidismo recién diagnosticado y que comenzó días antes de la consulta con un cuadro general inespecífico. Su evaluación ulterior demostró que se trataba de una tirotoxicosis aguda autoinmune, y su tratamiento con metimazol corrigió el trastorno totalmente. Se discuten los mecanismos fisiopatológicos involucrados y las implicancias clínicas desde el punto de vista del internista.Thyrotoxicosis may present with a variety of cardiovascular symptoms. Sinus tachycardia is the most frequently encountered electrocardiographic abnormality and conduction disturbances are extremely uncommon. We present a case of first degree atrio-ventricular block in a patient with newly diagnosed hyperthyroidism and discuss the underlying pathophysiological mechanisms and the clinical implications from the internist’s standpoint.

  2. Quantification of the relative contribution of the different right ventricular wall motion components to right ventricular ejection fraction: the ReVISION method.

    Science.gov (United States)

    Lakatos, Bálint; Tősér, Zoltán; Tokodi, Márton; Doronina, Alexandra; Kosztin, Annamária; Muraru, Denisa; Badano, Luigi P; Kovács, Attila; Merkely, Béla

    2017-03-27

    Three major mechanisms contribute to right ventricular (RV) pump function: (i) shortening of the longitudinal axis with traction of the tricuspid annulus towards the apex; (ii) inward movement of the RV free wall; (iii) bulging of the interventricular septum into the RV and stretching the free wall over the septum. The relative contribution of the aforementioned mechanisms to RV pump function may change in different pathological conditions.Our aim was to develop a custom method to separately assess the extent of longitudinal, radial and anteroposterior displacement of the RV walls and to quantify their relative contribution to global RV ejection fraction using 3D data sets obtained by echocardiography.Accordingly, we decomposed the movement of the exported RV beutel wall in a vertex based manner. The volumes of the beutels accounting for the RV wall motion in only one direction (either longitudinal, radial, or anteroposterior) were calculated at each time frame using the signed tetrahedron method. Then, the relative contribution of the RV wall motion along the three different directions to global RV ejection fraction was calculated either as the ratio of the given direction's ejection fraction to global ejection fraction and as the frame-by-frame RV volume change (∆V/∆t) along the three motion directions.The ReVISION (Right VentrIcular Separate wall motIon quantificatiON) method may contribute to a better understanding of the pathophysiology of RV mechanical adaptations to different loading conditions and diseases.

  3. Optical diffraction tomography techniques for the study of cell pathophysiology

    CERN Document Server

    Kim, Kyoohyun; Shin, Seungwoo; Lee, SangYun; Yang, Su-A; Park, YongKeun

    2016-01-01

    Three-dimensional imaging of biological cells is crucial for the investigation of cell biology, provide valuable information to reveal the mechanisms behind pathophysiology of cells and tissues. Recent advances in optical diffraction tomography (ODT) have demonstrated the potential for the study of various cells with its unique advantages of quantitative and label-free imaging capability. To provide insight on this rapidly growing field of research and to discuss its applications in biology and medicine, we present the summary of the ODT principle and highlight recent studies utilizing ODT with the emphasis on the applications to the pathophysiology of cells.

  4. Research progress of pathophysiological concepts in cerebral small vessel disease

    Directory of Open Access Journals (Sweden)

    Zai-qiang ZHANG

    2016-11-01

    Full Text Available The current definition of cerebral small vessels refers to all vascular structures ranging from 5 μ m to 2 mm in diameter in the brain parenchyma and they encompass small arteries, arterioles, capillaries, venules and small veins. Different diameters of cerebral small vessels have different distribution, and predilection to different types of pathophysiological process. Cerebral small vessel disease (cSVD, including lacunar infarct (LACI, white matter hyperintensity (WMH and cerebral microbleeds (CMBs, have different pathophysiological mechanisms and risk factors. Arterial stiffness is independently associated with all components of cSVD. DOI: 10.3969/j.issn.1672-6731.2016.11.007

  5. New insights into the pathophysiology of postoperative cognitive dysfunction

    DEFF Research Database (Denmark)

    Krenk, Lene; Rasmussen, Lars Simon; Kehlet, H

    2010-01-01

    There is evidence that postoperative cognitive dysfunction (POCD) is a significant problem after major surgery, but the pathophysiology has not been fully elucidated. The interpretation of available studies is difficult due to differences in neuropsychological test batteries as well as the lack...... of appropriate controls. Furthermore, there are no internationally accepted criteria for defining POCD. This article aims to provide an update of current knowledge of the pathogenesis of POCD with a focus on perioperative pathophysiology and possible benefits achieved from an enhanced postoperative recovery...

  6. Effects of inhaled iloprost on right ventricular contractility, right ventriculo-vascular coupling and ventricular interdependence: a randomized placebo-controlled trial in an experimental model of acute pulmonary hypertension

    Science.gov (United States)

    Rex, Steffen; Missant, Carlo; Claus, Piet; Buhre, Wolfgang; Wouters, Patrick F

    2008-01-01

    Introduction Prostacyclin inhalation is increasingly used to treat acute pulmonary hypertension and right ventricular failure, although its pharmacodynamic properties remain controversial. Prostacyclins not only affect vasomotor tone but may also have cAMP-mediated positive inotropic effects and modulate autonomic nervous system tone. We studied the role of these different mechanisms in the overall haemodynamic effects produced by iloprost inhalation in an experimental model of acute pulmonary hypertension. Methods In this prospective, randomized, placebo-controlled animal study, twenty-six pigs (mean weight 35 ± 2 kg) were instrumented with biventricular conductance catheters, a pulmonary artery flow probe and a high-fidelity pulmonary artery pressure catheter. The effects of inhaled iloprost (50 μg) were studied in the following groups: animals with acute hypoxia-induced pulmonary hypertension, and healthy animals with and without blockade of the autonomic nervous system. Results During pulmonary hypertension, inhalation of iloprost resulted in a 51% increase in cardiac output compared with placebo (5.6 ± 0.7 versus 3.7 ± 0.8 l/minute; P = 0.0013), a selective reduction in right ventricular afterload (effective pulmonary arterial elastance: 0.6 ± 0.3 versus 1.2 ± 0.5 mmHg/ml; P = 0.0005) and a significant increase in left ventricular end-diastolic volume (91 ± 12 versus 70 ± 20 ml; P = 0.006). Interestingly, right ventricular contractility was reduced after iloprost-treatment (slope of preload recruitable stroke work: 2.2 ± 0.5 versus 3.4 ± 0.8 mWatt·s/ml; P = 0.0002), whereas ventriculo-vascular coupling remained essentially preserved (ratio of right ventricular end-systolic elastance to effective pulmonary arterial elastance: 0.97 ± 0.33 versus 1.03 ± 0.15). In healthy animals, inhaled iloprost had only minimal haemodynamic effects and produced no direct effects on myocardial contractility, even after pharmacological blockade of the autonomic

  7. Taquicardia ventricular del tracto de salida del ventrículo derecho durante el embarazo Right ventricular outflow tachycardia during pregnancy

    Directory of Open Access Journals (Sweden)

    Ariel K. Saad

    2012-06-01

    Full Text Available Durante el embarazo aumentan el metabolismo basal, el consumo de O2, la frecuencia cardíaca, el volumen sistólico, el volumen minuto y la volemia y disminuyen la tensión arterial y la resistencia periférica. Diferentes estudios han demostrado que durante este período la posibilidad de que ocurra una arritmia cardíaca o se produzca la exacerbación de una arritmia preexistente es mayor. No obstante, en su enorme mayoría carecen de importancia pronóstica tanto para la madre como para el feto. La taquicardia ventricular del tracto de salida del ventrículo derecho es una arritmia poco frecuente y su aparición se ha correlacionado con el aumento del tono adrenérgico. Se presentan los casos de dos pacientes que mostraron en el curso de la gestación reiterados episodios de taquicardia ventricular del tracto de salida del ventrículo derecho. Se analiza la asociación del embarazo con la ocurrencia de trastornos del ritmo cardíaco.During pregnancy, there is an increase in metabolism, oxygen consumption, heart rate, stroke volume, cardiac output, blood volume and a decrease in blood pressure and peripheral resistance. Studies have shown that during this period the occurrence of cardiac arrhythmias is not uncommon. Fortunately, malignant arrhythmias are rare. Herein we report two young patients who presented with symptomatic right ventricular outflow tachycardia during pregnancy that required antiarrhythmic therapy. Possible pathophysiologic mechanisms are discussed.

  8. Myocardial protection of early extracorporeal membrane oxygenation (ECMO) support for acute myocardial infarction with cardiogenic shock in pigs.

    Science.gov (United States)

    Zhu, Gang-jie; Sun, Li-na; Li, Xing-hai; Wang, Ning-fu; Wu, Hong-hai; Yuan, Chen-xing; Li, Qiao-qiao; Xu, Peng; Ren, Ya-qi; Mao, Bao-gen

    2015-09-01

    The aim of this study was to explore myocardial protection of early extracorporeal membrane oxygenation (ECMO) support for acute myocardial infarction with cardiogenic shock in pigs. 24 male pigs (34.6 ± 1.3 kg) were randomly divided into three groups-control group, drug therapy group, and ECMO group. Myocardial infarction model was created in drug therapy group and ECMO group by ligating coronary artery. When cardiogenic shock occurred, drugs were given in drug therapy group and ECMO began to work in ECMO group. The pigs were killed 24 h after cardiogenic shock. Compared with in drug therapy group, left ventricular end-diastolic pressure in ECMO group decreased significantly 6 h after ligation (P myocardial infarct size of ECMO group did not reduce significantly, but myocardial enzyme and troponin-I decreased significantly. Compared with drug therapy, ECMO improves left ventricular diastolic function, and may improve systolic function. ECMO cannot reduce myocardial infarct size without revascularization, but may have positive effects on ischemic areas by avoiding further injuring.

  9. Mechanoelectric feedback does not contribute to the Frank-Starling relation in the rat and guinea pig heart

    Directory of Open Access Journals (Sweden)

    D Kelly

    2014-12-01

    Full Text Available Mechanoelectric feedback (MEF is the process by which mechanical forces on the myocardium can alter its electrical properties. The effect can be large enough to induce ectopic beats or fibrillation. However, the role of MEF at physiological levels of mechanical stress is not clear. We have investigated alteration in action potential morphology in rat and guinea pig ventricle and in rat atrial tissue at levels of stretch near the plateau of the Frank-Starling curve. Stretch of >100 mm.Hg End Diastolic Left Ventricular Pressure (EDLVP or rapidly applied stretch (EDLVP increased by 25 mm.Hg within 100 ms often triggered ectopic beats in isolated rat and guinea-pig hearts. However, ventricular epicardial monophasic action potentials (MAPs recorded during stretch to EDLVP up to 30 mm. Hg showed no consistent changes in action potential duration (at APD20, APD50 or APD80 in either species. MAP recording detected APD prolongation with very small concentrations of 4-AP (10 μM, confirming the discrimination of the recording technique. In isolated rat atrial strips, no changes in intracellular action potential morphology or membrane potential were seen when stretched to levels producing an optimum increase in contractility. We conclude that alteration in action potential morphology with stretch does not contribute to the Frank-Starling relation in ventricle of rat or guinea-pig isolated heart, or in rat atrial tissue.

  10. Treatment of asymptomatic catecholaminergic polymorphic ventricular tachycardia.

    Science.gov (United States)

    Obeyesekere, Manoj N; Sy, Raymond W; Leong-Sit, Peter; Gula, Lorne J; Yee, Raymond; Skanes, Allan C; Klein, George J; Krahn, Andrew D

    2012-05-01

    Catecholaminergic polymorphic ventricular tachycardia is a rare genetic disorder caused by mutations in genes involved in the intracellular calcium homeostasis of cardiac cells. Affected patients typically present with life-threatening ventricular arrhythmias precipitated by emotional/physical stress. The diagnosis is based on the demonstration of polymorphic or bidirectional ventricular tachycardia associated with adrenergic stress. Genetic testing can be confirmatory in some patients. Treatment for catecholaminergic polymorphic ventricular tachycardia includes medical and surgical efforts to suppress the effects of epinephrine at the myocardial level and/or modulation of calcium homeostasis. Mortality is high when untreated and sudden cardiac death may be the first manifestation of the disease. First-degree relatives of a proband should be offered genetic testing if the causal mutation is known. If the family mutation is not known, relatives should be clinically evaluated with provocative testing. In the absence of rigorous trials, prophylactic treatment of the asymptomatic catecholaminergic polymorphic ventricular tachycardia patient appears to reduce morbidity and mortality.

  11. Surgical Treatment of Left Ventricular Pseudoaneurysm

    Science.gov (United States)

    Mujanovic, Emir; Bergsland, Jacob; Avdic, Sevleta; Stanimirovic-Mujanovic, Sanja; Kovacevic-Preradovic, Tamara; Kabil, Emir

    2014-01-01

    Introduction: Left ventricular pseudoaneurysm is a rare condition because in most instances ventricular free-wall rupture leads to fatal pericardial tamponade. Rupture of the free wall of the left ventricle is a cata­strophic complication of myocardial infarction, occurring in approximately 4% of pa­tients with infarcts, resulting in immediate collapse of the patient and electromechanical dissociation. In rare cases the rupture is contained by pericardial and fibrous tissue, and the result is a pseudoaneurysm. The left ventricular pseudoaneurysm contains only pericardial and fibrous elements in its wall-no myocardial tissue. Because such aneurysms have a strong tendency to rupture, this disorder may lead to death if it is left surgically untreated. Case report: In this case report, we present a patient who underwent successful repair of a left ventricular pseudoaneurysm, which followed a myocardial infarction that was caused by occlusion of the left circumflex coronary artery. Although repair of left ventricular pseudoaneurysm is still a surgical challenge, it can be performed with acceptable results in most patients. PMID:25568538

  12. Metabolomic phenotyping of a cloned pig model

    Directory of Open Access Journals (Sweden)

    Callesen Henrik

    2011-08-01

    Full Text Available Abstract Background Pigs are widely used as models for human physiological changes in intervention studies, because of the close resemblance between human and porcine physiology and the high degree of experimental control when using an animal model. Cloned animals have, in principle, identical genotypes and possibly also phenotypes and this offer an extra level of experimental control which could possibly make them a desirable tool for intervention studies. Therefore, in the present study, we address how phenotype and phenotypic variation is affected by cloning, through comparison of cloned pigs and normal outbred pigs. Results The metabolic phenotype of cloned pigs (n = 5 was for the first time elucidated by nuclear magnetic resonance (NMR-based metabolomic analysis of multiple bio-fluids including plasma, bile and urine. The metabolic phenotype of the cloned pigs was compared with normal outbred pigs (n = 6 by multivariate data analysis, which revealed differences in the metabolic phenotypes. Plasma lactate was higher for cloned vs control pigs, while multiple metabolites were altered in the bile. However a lower inter-individual variability for cloned pigs compared with control pigs could not be established. Conclusions From the present study we conclude that cloned and normal outbred pigs are phenotypically different. However, it cannot be concluded that the use of cloned animals will reduce the inter-individual variation in intervention studies, though this is based on a limited number of animals.

  13. Pigs taking wing with transposons and recombinases

    Science.gov (United States)

    Clark, Karl J; Carlson, Daniel F; Fahrenkrug, Scott C

    2007-01-01

    Swine production has been an important part of our lives since the late Mesolithic or early Neolithic periods, and ranks number one in world meat production. Pig production also contributes to high-value-added medical markets in the form of pharmaceuticals, heart valves, and surgical materials. Genetic engineering, including the addition of exogenous genetic material or manipulation of the endogenous genome, holds great promise for changing pig phenotypes for agricultural and medical applications. Although the first transgenic pigs were described in 1985, poor survival of manipulated embryos; inefficiencies in the integration, transmission, and expression of transgenes; and expensive husbandry costs have impeded the widespread application of pig genetic engineering. Sequencing of the pig genome and advances in reproductive technologies have rejuvenated efforts to apply transgenesis to swine. Pigs provide a compelling new resource for the directed production of pharmaceutical proteins and the provision of cells, vascular grafts, and organs for xenotransplantation. Additionally, given remarkable similarities in the physiology and size of people and pigs, swine will increasingly provide large animal models of human disease where rodent models are insufficient. We review the challenges facing pig transgenesis and discuss the utility of transposases and recombinases for enhancing the success and sophistication of pig genetic engineering. 'The paradise of my fancy is one where pigs have wings.' (GK Chesterton). PMID:18047690

  14. Citric Acid Cycle Metabolites Predict the Severity of Myocardial Stunning and Mortality in Newborn Pigs.

    Science.gov (United States)

    Hyldebrandt, Janus Adler; Støttrup, Nicolaj Brejnholt; Frederiksen, Christian Alcaraz; Heiberg, Johan; Dupont Birkler, Rune Isak; Johannsen, Mogens; Schmidt, Michael Rahbek; Ravn, Hanne Berg

    2016-12-01

    Myocardial infarction and chronic heart failure induce specific metabolic changes in the neonatal myocardium that are closely correlated to outcome. The aim of this study was to examine the metabolic responses to noninfarct heart failure and inotropic treatments in the newborn heart, which so far are undetermined. A total of 28 newborn pigs were instrumented with a microdialysis catheter in the right ventricle, and intercellular citric acid cycle intermediates and adenosine metabolite concentrations were determined at 20-minute intervals. Stunning was induced by 10 cycles of 3 minutes of ischemia, which was performed by occluding the right coronary artery, followed by 3 minutes of reperfusion. Animals were randomized for treatment with epinephrine + milrinone, dopamine + milrinone, dobutamine, or saline. University hospital animal laboratory. Ischemia-reperfusion induced right ventricular stunning and increased the concentrations of pyruvate lactate, succinate, malate, hypoxanthine, and xanthine (all, p citric acid cycle intermediates and adenosine metabolites reflects the presence of myocardial stunning and predicts mortality in acute noninfarct right ventricular heart failure in newborn pigs. This phenomenon occurs independently of the type of inotrope, suggesting that citric acid cycle intermediates represent potential markers of acute noninfarct heart failure.

  15. Excitation-contraction coupling in rested-state contractions of guinea-pig ventricular myocardium.

    Science.gov (United States)

    Reiter, M; Vierling, W; Seibel, K

    1984-02-01

    Different types of rested-state contractions were examined under the influence of various inotropic agents. In magnesium-free solution, in low sodium (40 mmol/l) solution or in the presence of dihydroouabain, an "early" rested-state contraction developed without delay after stimulation. A distinctive "late" rested-state contraction was observed under the influence of noradrenaline. It is characterized by a latent period of about 100 ms between stimulation and onset of contraction. This latency was not reduced by increasing the catecholamine concentration, despite a concentration-dependent increase in the height of the "late" rested-state contraction. The late rested-state contraction under the influence of noradrenaline was suppressed by the slow inward current inhibitor nifedipine whether or not the nifedipine-dependent shortening of the action potential duration was prevented by caesium. When the slow inward current was not inhibited, the prolongation of the action potential duration by caesium resulted in an increase of the late rested-state contraction because of a prolongation of the time to peak force. High concentrations of dihydroouabain led to the appearance of an early contraction component without appreciably influencing the noradrenaline-dependent late component. From this it was deduced that the activator calcium for the late rested-state contraction was not stored intracellularly during rest prior to stimulation and, consequently, could not have been released by inflowing calcium. Instead, it is proposed that the activator calcium for the late rested-state contraction entered the sites of the sarcoplasmic reticulum and subsequently released from its release sites as long as the cell was depolarized. The "early" rested-state contractions in Mg2+-free solution, in low sodium solution or in the presence of dihydroouabain were not influenced in their contraction velocity by high concentrations of nifedipine which fully inhibited the late rested-state contractions. Nifedipine caused only a slight reduction in peak force due to a shortening of the time to peak force as a result of a shortening in action potential duration. This indicates that the activator calcium for the "early" rested-state contractions had accumulated in the sarcoplasmic reticulum during rest prior to stimulation and that it was released immediately by depolarization without a participation of the slow inward current.

  16. Chamber-specific effects of hypokalaemia on ventricular arrhythmogenicity in isolated, perfused guinea-pig heart

    DEFF Research Database (Denmark)

    Osadchii, Oleg E; Bentzen, Bo Hjorth; Olesen, Søren-Peter

    2009-01-01

    Diuretic-induced hypokalaemia has been shown to promote cardiac arrhythmias in hypertensive patients. The present study was designed to determine whether hypokalaemia increases arrhythmic susceptibility of the left ventricle (LV) or the right ventricle (RV), or both. Proarrhythmic effects of hypo...

  17. Incorporated sarcolemmal fish oil fatty acids shorten pig ventricular action potentials

    NARCIS (Netherlands)

    Verkerk, A.O.; Ginneken, van A.C.G.; Berecki, G.; Ruijter, den H.M.; Schumacher, C.A.; Veldkamp, M.W.; Baartscheer, A.; Casini, S.; Opthof, T.; Hovenier, R.; Fiolet, J.W.T.; Zock, P.L.; Coronel, R.

    2006-01-01

    Background: Omega-3 polyunsaturated fatty acids (W-PUFAs) from fish oil reduce the risk of sudden death presumably by preventing life-threatening arrhythmias. Acutely administered omega 3-PUFAs modulate the activity of several cardiac ion channels, but the chronic effects of a diet enriched with fis

  18. Incorporated sarcolemmal fish oil fatty acids shorten pig ventricular action potentials

    NARCIS (Netherlands)

    Verkerk, A.O.; Ginneken, van A.C.G.; Berecki, G.; Ruijter, den H.M.; Schumacher, C.A.; Veldkamp, M.W.; Baartscheer, A.; Casini, S.; Opthof, T.; Hovenier, R.; Fiolet, J.W.T.; Zock, P.L.; Coronel, R.

    2006-01-01

    Background: Omega-3 polyunsaturated fatty acids (W-PUFAs) from fish oil reduce the risk of sudden death presumably by preventing life-threatening arrhythmias. Acutely administered omega 3-PUFAs modulate the activity of several cardiac ion channels, but the chronic effects of a diet enriched with fis

  19. Incorporated sarcolemmal fish oil fatty acids shorten pig ventricular action potentials

    NARCIS (Netherlands)

    Verkerk, A.O.; Ginneken, van A.C.G.; Berecki, G.; Ruijter, den H.M.; Schumacher, C.A.; Veldkamp, M.W.; Baartscheer, A.; Casini, S.; Opthof, T.; Hovenier, R.; Fiolet, J.W.T.; Zock, P.L.; Coronel, R.

    2006-01-01

    Background: Omega-3 polyunsaturated fatty acids (W-PUFAs) from fish oil reduce the risk of sudden death presumably by preventing life-threatening arrhythmias. Acutely administered omega 3-PUFAs modulate the activity of several cardiac ion channels, but the chronic effects of a diet enriched with

  20. 介入封堵左前降支建立室壁瘤动物模型%Ventricular aneurysm animal model establishment by plugging the left anterior descending branch

    Institute of Scientific and Technical Information of China (English)

    张倞; 张绍明; 王永武; 徐文俊; 蒋金法; 邵杰

    2009-01-01

    erected; ST-T fusion wave appeared; precordial leads were obvious. ST segment was reduced to basic level 2 week later, and pathological Q wave appeared 4 weeks later. Serum treponin was increased at 12 hears following surgery compared with before surgery (P < 0.01). Radioactive nuclide myocardial imaging revealed that cardiac apex and left ventdcle anterior wall showed radioactive nuclide perfusion filling defect, thin ventricular wall and ventricular aneurysm. Cardiac ultrasonic showed six pigs suffered from weaken segmentation contraction motor of local ventricular wall, especially at anterior wall of the left ventricle and cardiac apex. After hematoxylin-eesin staining, optical microscope exhibited that cardiac muscle fiber disappeared, which was replaced by collagen fiber, with the presence of some capillary at the infarct of cardiac apex. Pyknosis and lysis of residual cardiac muscle fiber were visible in infarct region of anterior wall of the right ventricle. Many inflammatory cells and capillary infiltration were detected besides collagen fiber filling. CONCLUSION: The new approach of "WYW" intervention embolization is able to develop the ventricular aneurysm animal model, which is similar to clinical pathophysiological variation. The outcome is precise and reliable.

  1. Exploring pig raising in Bangladesh: implications for public health interventions

    Directory of Open Access Journals (Sweden)

    Stephen P. Luby

    2013-03-01

    Full Text Available Pigs are intermediate hosts and potential reservoirs of a number of pathogens that can infect humans. The objectives of this manuscript are to understand pig raising patterns in Bangladesh, interactions between pigs and humans, social stigma and discrimination that pig raisers experience and to explore the implications of these findings for public health interventions. The study team conducted an exploratory qualitative study by interviewing backyard pig raisers and nomadic herders (n = 34, observing daily interactions between pigs and humans (n = 18 and drawing seasonal diagrams (n = 6 with herders to understand the reasons for movement of nomadic herds. Pig raisers had regular close interaction with pigs. They often touched, caressed and fed their pigs which exposed them to pigs' saliva and feces. Herders took their pigs close to human settlements for scavenging. Other domestic animals and poultry shared food and sleeping and scavenging places with pigs. Since pigs are taboo in Islam, a majority of Muslims rejected pig raising and stigmatized pig raisers. This study identified several potential ways for pigs to transmit infectious agents to humans in Bangladesh. Poverty and stigmatization of pig raisers make it difficult to implement health interventions to reduce the risk of such transmissions. Interventions that offer social support to reduce stigma and highlight economic benefits of disease control might interest of pig raisers in accepting interventions targeting pig borne zoonoses.

  2. Exploring pig raising in Bangladesh: implications for public health interventions.

    Science.gov (United States)

    Nahar, Nazmun; Uddin, Main; Sarkar, Rouha Anamika; Gurley, Emily S; Uddin Khan, M Salah; Hossain, M Jahangir; Sultana, Rebeca; Luby, Stephen P

    2013-01-01

    Pigs are intermediate hosts and potential reservoirs of a number of pathogens that can infect humans. The objectives of this manuscript are to understand pig raising patterns in Bangladesh, interactions between pigs and humans, social stigma and discrimination that pig raisers experience and to explore the implications of these findings for public health interventions. The study team conducted an exploratory qualitative study by interviewing backyard pig raisers and nomadic herders (n=34), observing daily interactions between pigs and humans (n=18) and drawing seasonal diagrams (n=6) with herders to understand the reasons for movement of nomadic herds. Pig raisers had regular close interaction with pigs. They often touched, caressed and fed their pigs which exposed them to pigs' saliva and feces. Herders took their pigs close to human settlements for scavenging. Other domestic animals and poultry shared food and sleeping and scavenging places with pigs. Since pigs are taboo in Islam, a majority of Muslims rejected pig raising and stigmatized pig raisers. This study identified several potential ways for pigs to transmit infectious agents to humans in Bangladesh. Poverty and stigmatization of pig raisers make it difficult to implement health interventions to reduce the risk of such transmissions. Interventions that offer social support to reduce stigma and highlight economic benefits of disease control might interest of pig raisers in accepting interventions targeting pig borne zoonoses.

  3. Assessment of welfare in pigs

    Directory of Open Access Journals (Sweden)

    Luisa Antonella Volpelli

    2010-01-01

    Full Text Available According to the definition given by Appleby (1996, animal welfare represents the state of well-being brought about by meeting the physical, environmental, nutritional, behavioural and social needs of the animal or groups of animals under the care, supervision or influence of people. Suitable husbandry techniques and disease control (in which man is directly involved may satisfy an animal’s physical, environmental and nutritive needs. However, it cannot be stated that people’s supervision or influence always guarantee the satisfaction of behavioural and social needs. Thus, special attention must be paid to these factors in intensive husbandry. This paper calls attention to the main factors characterizing pig welfare on the basis of productive, physiological, pathological and behavioural indicators; to the behavioural needs, which are characterised by several peculiar traits (it is noteworthy that, since the beginning, all categories of reared pigs have been involved in welfare legislation; to all categories of pigs that often show the effects of negative stimuli on their behaviour (limitations, variations; to the main critical points on the farm likely to cause welfare impairment or stress including buildings, inner facilities, space allowance, microclimate, lighting systems, environmental stressors, feeding management, mutilations, weaning, social factors, and stockmanship; and to environmental stressors including dust, odours (especially ammonia and noises. This paper takes into account sources, effects and possible solutions for noises; the positive effect of fibrous feeding; environmental enrichment and other possible techniques for improving social status and for preventing/reducing stereotypic behaviour and abnormal reactions (e.g. tail biting. The scientific/objective evaluation of welfare for intensively reared pigs may be carried out by means of direct observation of the animals themselves (animal-based or encompassing performance

  4. Pathophysiology of acute mountain sickness and high altitude pulmonary oedema

    DEFF Research Database (Denmark)

    Sutton, J R; Lassen, N

    1979-01-01

    We review the evidence that acute mountain sickness (AMS) and high altitude pulmonary oedema (HAPO) occur together more often than is realized. We hypothesize that AMS and HAPO have a common pathophysiological basis: both are due to increased pressure and flow in the microcirculation, causing...

  5. Pathophysiology of Tonic Muscle Activation During Epileptic Seizures

    DEFF Research Database (Denmark)

    Beniczky, S.; Conradsen, Isa; Wolf, P.

    2011-01-01

    , quantitative analysis of the sEMG during the epileptic seizures has received surprisingly little attention. The aim of our study was to elucidate the pathophysiology of the tonic muscle activation during seizures. SEMG was recorded from the deltoid muscles, during 58 seizures from 18 patients (9...

  6. The role of autoantibodies in the pathophysiology of rheumatoid arthritis.

    Science.gov (United States)

    Derksen, V F A M; Huizinga, T W J; van der Woude, D

    2017-06-01

    Rheumatoid arthritis (RA) is an autoimmune disease characterized by joint inflammation. The presence of autoantibodies in the sera of RA patients has provided many clues to the underlying disease pathophysiology. Based on the presence of several autoantibodies like rheumatoid factor (RF), anti-citrullinated protein antibodies (ACPA), anti-carbamylated protein antibodies (anti-CarP), and more recently anti-acetylated protein antibodies RA can be subdivided into seropositive and seronegative disease. The formation of these autoantibodies is associated with both genetic and environmental risk factors for RA, like specific human leukocyte antigen (HLA) alleles and smoking. Autoantibodies can be detected many years before disease onset in a subset of patients, suggesting a sequence of events in which the first autoantibodies develop in predisposed hosts, before an inflammatory response ensues leading to clinically apparent arthritis. Research on the characteristics and effector functions of these autoantibodies might provide more insight in pathophysiological processes underlying arthritis in RA. Recent data suggests that ACPA might play a role in perpetuating inflammation once it has developed. Furthermore, pathophysiological mechanisms have been discovered supporting a direct link between the presence of ACPA and both bone erosions and pain in RA patients. In conclusion, investigating the possible pathogenic potential of autoantibodies might lead to improved understanding of the underlying pathophysiological processes in rheumatoid arthritis.

  7. Idiopathic Intracranial Hypertension – Pathophysiology Based on Case Series

    Directory of Open Access Journals (Sweden)

    Ljubisavljević Srdjan

    2016-09-01

    Full Text Available According to the definition, idiopathic intracranial hypertension (IIH is a pathological state characterized by an increase in intracranial pressure; however, there are no obvious intracranial pathological processes. The pathophysiology of this disorder is not clear, although there are many reports related to it.

  8. Pathophysiology and treatment of edema following femoropopliteal bypass surgery

    NARCIS (Netherlands)

    te Slaa, A.; Dolmans, D. E. J. G. J.; Ho, G. H.; Moll, F. L.; van der Laan, L.

    2012-01-01

    Substantial lower-limb edema affects the majority of patients who undergo peripheral bypass surgery. Edema has impairing effects on the microvascular and the macrovascular circulation, causes discomfort and might delay the rehabilitation process of the patient. However, the pathophysiology of this e

  9. The pathophysiology of essential tremor and Parkinson's tremor

    NARCIS (Netherlands)

    Helmich, R.C.G.; Toni, I.; Deuschl, G.; Bloem, B.R.

    2013-01-01

    We review recent evidence about the pathophysiology of essential tremor and tremor in Parkinson's disease. We believe that a network perspective is necessary to understand this common neurological symptom, and that knowledge of cerebral network dysfunction in tremor disorders will help to develop ne

  10. The Pathophysiology of Essential Tremor and Parkinson's Tremor

    NARCIS (Netherlands)

    Helmich, R.C.G.; Toni, I.; Deuschl, G.; Bloem, B.R.

    2013-01-01

    We review recent evidence about the pathophysiology of essential tremor and tremor in Parkinson's disease. We believe that a network perspective is necessary to understand this common neurological symptom, and that knowledge of cerebral network dysfunction in tremor disorders will help to develop ne

  11. Unravelling narcolepsy : from pathophysiology to measuring treatment effects

    NARCIS (Netherlands)

    Heide, van der A.

    2017-01-01

    Narcolepsy is a disorder of the regulation of sleep and wakefulness, with as its major features excessive daytime sleepiness (EDS), cataplexy, hypnagogic hallucinations, sleep paralysis and disturbed nocturnal sleep. The first part of this thesis concernes an overview of the pathophysiology,

  12. Parkinson's disease : The syndrome, the pathogenesis and pathophysiology

    NARCIS (Netherlands)

    Bartels, Anna L.; Leenders, Klaus L.

    Parkinson's disease (PD) is characterised by a slowly expanding degeneration of neurons particularly in the mesencephalon. The causes are unknown although risk factors in the genetic and toxic domain are being discovered. An important pathophysiological feature in PD is the loss of part of the

  13. New insights into the pathophysiology of postoperative cognitive dysfunction

    DEFF Research Database (Denmark)

    Krenk, Lene; Rasmussen, Lars Simon; Kehlet, H

    2010-01-01

    There is evidence that postoperative cognitive dysfunction (POCD) is a significant problem after major surgery, but the pathophysiology has not been fully elucidated. The interpretation of available studies is difficult due to differences in neuropsychological test batteries as well as the lack o...... minimal invasive surgery, multi-modal non-opioid pain management and pharmacological manipulation of the inflammatory response and sleep architecture....

  14. Reverse Engineering Human Pathophysiology with Organs-on-Chips.

    Science.gov (United States)

    Ingber, Donald E

    2016-03-10

    While studies of cultured cells have led to new insights into biological control, greater understanding of human pathophysiology requires the development of experimental systems that permit analysis of intercellular communications and tissue-tissue interactions in a more relevant organ context. Human organs-on-chips offer a potentially powerful new approach to confront this long-standing problem.

  15. Epidemiology, Pathophysiology, and the Future of Ocular Toxoplasmosis

    NARCIS (Netherlands)

    Kijlstra, A.; Pedersen, E.

    2014-01-01

    Despite large advances in the field of ocular toxoplasmosis, large gaps still exist in our knowledge concerning the epidemiology and pathophysiology of this potentially blinding infectious disease. Although ocular toxoplasmosis is considered to have a high health burden, still little is known about

  16. Streptozotocin-Induced Diabetes Models: Pathophysiological Mechanisms and Fetal Outcomes

    Directory of Open Access Journals (Sweden)

    D. C. Damasceno

    2014-01-01

    Full Text Available Glucose homeostasis is controlled by endocrine pancreatic cells, and any pancreatic disturbance can result in diabetes. Because 8% to 12% of diabetic pregnant women present with malformed fetuses, there is great interest in understanding the etiology, pathophysiological mechanisms, and treatment of gestational diabetes. Hyperglycemia enhances the production of reactive oxygen species, leading to oxidative stress, which is involved in diabetic teratogenesis. It has also been suggested that maternal diabetes alters embryonic gene expression, which might cause malformations. Due to ethical issues involving human studies that sometimes have invasive aspects and the multiplicity of uncontrolled variables that can alter the uterine environment during clinical studies, it is necessary to use animal models to better understand diabetic pathophysiology. This review aimed to gather information about pathophysiological mechanisms and fetal outcomes in streptozotocin-induced diabetic rats. To understand the pathophysiological mechanisms and factors involved in diabetes, the use of pancreatic regeneration studies is increasing in an attempt to understand the behavior of pancreatic beta cells. In addition, these studies suggest a new preventive concept as a treatment basis for diabetes, introducing therapeutic efforts to minimize or prevent diabetes-induced oxidative stress, DNA damage, and teratogenesis.

  17. Glucocorticoid-induced myopathy: Pathophysiology, diagnosis, and treatment

    Directory of Open Access Journals (Sweden)

    Anu Gupta

    2013-01-01

    Full Text Available Glucocorticoid-induced myopathy is the most common type of drug-induced myopathy. Nearly 60% of patients with Cushing′s syndrome have muscle weakness. Glucocorticoid-induced muscle atrophy affects mainly fast-twitch glycolytic muscle fibers (type IIb fibers. This brief review will discuss the pathophysiology behind glucocorticoid-induced myopathy, along with diagnostic features and treatment.

  18. Insulin resistance : pathophysiology in South Asians & therapeutic strategies

    NARCIS (Netherlands)

    Sleddering, Maria Alexandra

    2014-01-01

    This thesis describes the pathophysiology of insulin resistance in the South Asian population and comprises studies on pharmacological and weight loss interventions in insulin resistant patients. Because of the increasing number of patients with obesity and T2DM, more research is needed to identify

  19. Insulin resistance : pathophysiology in South Asians & therapeutic strategies

    NARCIS (Netherlands)

    Sleddering, Maria Alexandra

    2014-01-01

    This thesis describes the pathophysiology of insulin resistance in the South Asian population and comprises studies on pharmacological and weight loss interventions in insulin resistant patients. Because of the increasing number of patients with obesity and T2DM, more research is needed to identify

  20. Pathophysiology and treatment of edema following femoropopliteal bypass surgery

    NARCIS (Netherlands)

    te Slaa, A.; Dolmans, D. E. J. G. J.; Ho, G. H.; Moll, F. L.; van der Laan, L.

    2012-01-01

    Substantial lower-limb edema affects the majority of patients who undergo peripheral bypass surgery. Edema has impairing effects on the microvascular and the macrovascular circulation, causes discomfort and might delay the rehabilitation process of the patient. However, the pathophysiology of this e

  1. Pathophysiological Mechanisms of Severe Anaemia in Malawian Children

    NARCIS (Netherlands)

    M.B. van Hensbroek; J.C.J. Calis; K.S. Phiri; R. de Vet; F. Munthali; R. Kraaijenhagen; H. van den Berg; B. Faragher; I. Bates; M.E. Molyneux

    2010-01-01

    Background: Severe anaemia is a major cause of morbidity and mortality in African children. The aetiology is multi-factorial, but interventions have often targeted only one or a few causal factors, with limited success. Methods and Findings: We assessed the contribution of different pathophysiologic

  2. GENETIC ANALYSIS OF BLACK SLAVONIAN PIG

    Directory of Open Access Journals (Sweden)

    Vladimir Margeta

    2012-12-01

    Full Text Available Pairs (18 of microsatelite primers were used in this study to detect the genetic relationship within Black Slavonian Pig and between Turopolje Pig, Mangalitsa breed and Croatian Wild Pigs. The second goal of this study was to determine phylogenetic relationships among these breeds and some Asian and European pigs using the mtDNA D-loop sequence polymorphism. The third goal was to determine the MC1R genotype of Black Slavonian pigs and to find an efficient and simple PCR-RFLP method, based on differences in MC1R genotype, to distinguish between purebred Black Slavonian pigs and their crossings with commercial pig breeds and Wild Boars. Aiming to conduct microsatellite analysis each animal was genotyped for 18 microsatelite markers, chosen based on their quality, size, polymorphism and location on the porcine genome as proposed by the FAO. Two pairs of primers amplified a 511-bp fragment of control region between sites 15 390 and 15 900 (Mit1.F and Mit1.R and a 810-bp fragment between sites 15 825 and 16 634 (Mit2.F and Mi2.R were genotyped for mtDNA. Two primer pairs were used to amplify the majority of the single exon of MC1R gene aiming to determinate MC1R genotype of Black Slavonian pig. The first pair of primers, MERL1 and EPIG2, was used to amplify a 428-bp product from the 5’ half of the exon, whereas EPIG1 and EPIG3 amplified a 405-bp product from the 3’ half. Our results showed that the 18 microsatellites used in this study were useful markers to study genetic diversity among Croatian autochthonous pig breeds. This set of microsatellites may be used for identifying individuals and for genetic diversity studies for selection and conservation of the Black Slavonian pig, Turopolje pig and Mangalitsa breed. Genetic distances between populations made with Principal Component Analysis (PCA method noticed that studied populations are mostly clearly geneticaly defined. mtDNA analysis suggested that Black Slavonian and Turopolje pig showed

  3. Comparative gastric morphometry of Muong indigenous and Vietnamese wild pigs

    National Research Council Canada - National Science Library

    Trang, Pham Hong; Ooi, Peck Toung; Zuki, Abu Bakar Zakaria; Noordin, Mustapha Mohamed

    2012-01-01

    .... Due to the protective nature of procuring these pigs, a total of 12 Muong indigenous pigs and nine Vietnamese wild pigs stomach collected post mortem were analysed for selected biometric parameters and histology...

  4. 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.

  5. MRI assessment of right ventricular dysplasia

    Energy Technology Data Exchange (ETDEWEB)

    Di Cesare, Ernesto [Department of Radiology, University of L' Aquila, via Vetoio 1, 67100, L' Aquila (Italy)

    2003-06-01

    Right ventricular dysplasia is a new entity of unknown origin in the classification of cardiomyopathies. Also known as arrhythmogenic right ventricular cardiomyopathy (ARVC) or arrhythmogenic right ventricular dysplasia, it is a disease of the heart muscle characterised by fibroadipose atrophy mainly involving the right ventricle and responsible for severe ventricular arrhythmias and sudden death also in young people. Magnetic resonance imaging provides evidence of ventricular dilatation at the outflow tract, thinning and thickening of the wall, diastolic bulging areas (especially located at the level of the right ventricle outflow tract) and fatty substitution of the myocardium mainly at the level of the right ventricle. Many radiologists erroneously consider the previously described fatty substitution as the main sign of ARVC, even though an evaluation of fat substitution alone may be a source of error for two reasons: firstly, because isolated areas of fatty replacement are not synonymous with ARVC since small non-transmural focal fatty areas of fat are also present in the normal patients; and secondly, because the MRI detection of fat may be overestimated due to partial-volume artefacts with normal subepicardial fat. Cardiac MRI can also be employed for the diagnosis of idiopathic right ventricular outflow tract tachycardia. Considering the evolutive nature of the disease, the non-invasiveness of MRI allows the follow-up of these patients and may be considered an excellent screening modality for the diagnosis of ARVC in family members. Finally, MRI can be employed in electrophysiological studies to locate the arrhythmogenic focus and reduce sampling errors. (orig.)

  6. Evaluation of right ventricular volumes measured by magnetic resonance imaging

    DEFF Research Database (Denmark)

    Møgelvang, J; Stubgaard, M; Thomsen, C

    1988-01-01

    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...... 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...... 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...

  7. Endoventriculoplasty using autologous endocardium for anterior left ventricular aneurysms

    NARCIS (Netherlands)

    Grandjean, JG; Mariani, MA; D'Alfonso, A; Musazzi, A; Boonstra, PW

    Background: There is currently consensus that endoventriculoplasty is the treatment of choice for an anterior left ventricular aneurysm. We describe here a new technique of endoventriculoplasty using autologous endocardium for left ventricular anterior aneurysm. Method: From 1990 until 2003, 49

  8. New ECG Criteria in Arrhythmogenic Right Ventricular Dysplasia/Cardiomyopathy

    NARCIS (Netherlands)

    M.G.P.J. Cox; J.J. van der Smagt; A.A.M. Wilde; A.C.P. Wiesfeld; D.E. Atsma; M.R. Nelen; L.M. Rodriguez; P. Loh; M.J. Cramer; P.A. Doevendans; J.P. van Tintelen; J.M.T. de Bakker; R.N.W. Hauer

    2009-01-01

    Background-Desmosomal changes, electric uncoupling, and surviving myocardial bundles in fibrofatty tissue characterize arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C). Resultant activation delay is pivotal for reentry and thereby ventricular tachycardia (VT). Current task force cr

  9. Ventricular Tachycardia Induced by Weight Loss Pills

    Directory of Open Access Journals (Sweden)

    Manan Pareek

    2013-01-01

    Full Text Available 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.

  10. Ventricular arrhythmias. Clinical recognition and management.

    Science.gov (United States)

    Nestico, P F; DePace, N L; Morganroth, J

    1984-05-01

    The recognition that patients at high risk for sudden cardiac death can be identified raises our enthusiasm to eliminate some of these risk factors and thus our hope to prevent sudden cardiac death. Although this effect is yet to be shown in cooperative, well-controlled clinical trials, data exist to suggest that this result will be achieved. Thus, the use of antiarrhythmic agents in chronic ventricular ectopy, particularly in patients with left ventricular dysfunction, seems to be warranted, and new and more potent agents to be used for this end will be available in the future.

  11. Right ventricular cardiomyopathy meeting the arrhythmogenic right ventricular dysplasia revised criteria? Do not forget sarcoidosis

    Energy Technology Data Exchange (ETDEWEB)

    Vasaturo, Sabina; Ploeg, David E.; Zeppenfeld, Katja; Veselic-Charvat, Maud [Leiden University Medical Center, Leiden (Netherlands); Buitrago, Guadalupe [Dept. of Radiology, Hospital General Universitario Gregorio Maranon, Madrid (Spain)

    2015-06-15

    A 53-year-old woman was referred for ventricular fibrillation with resuscitation. A CT-angiography showed signs of a right ventricular enlargement without obvious cause. A cardiac MRI demonstrated a dilated and hypokinetic right ventricle with extensive late gadolinium enhancement. Arrhythmogenic right ventricular dysplasia (ARVD) was suspected according to the {sup r}evised ARVD task force criteria{sup .} An endomyocardial biopsy was inconclusive. The patient developed purulent pericarditis after epicardial ablation therapy and died of toxic shock syndrome. The post-mortem pathologic examination demonstrated sarcoidosis involving the heart, lungs, and thyroid gland.

  12. Left ventricular cardiac fibroma in a child presenting with ventricular tachycardia.

    Science.gov (United States)

    Stratemann, Stacy; Dzurik, Yvette; Fish, Frank; Parra, David

    2008-01-01

    Cardiac tumors in children are rare. Although most are histologically benign, they can be associated with life-threatening arrhythmias and sudden death. We report a 7-year-old boy, with a first episode of symptomatic tachycardia, who was found to have a left ventricular (LV) fibroma. He had a normal echocardiogram prior to an electrophysiology study, which revealed a sustained monomorphic ventricular tachycardia and a radio-opacity near the LV apex. These findings prompted a cardiac MRI, which demonstrated a discrete mass on his LV apex and free wall. Our case emphasizes that structural heart disease should be aggressively pursued in children presenting with ventricular tachycardia.

  13. Anaerobic digestion of pig manure fibres from commercial pig slurry separation units

    DEFF Research Database (Denmark)

    Thygesen, Ole; Triolo, Jin M.; Sommer, Sven G.

    2014-01-01

    The composition of manure fibres (MF) from 17 commercially separated pig slurries and seven raw pig slurries were characterised in terms of dry matter (DM), volatile solids (VS), protein, hemicellulose, cellulose and lignin. The average lignocellulose concentration in manure fibres and pig slurries...

  14. Speckle-tracking echocardiography elucidates the effect of pacing site on left ventricular synchronization in the normal and infarcted rat myocardium.

    Directory of Open Access Journals (Sweden)

    Michal Mor

    Full Text Available BACKGROUND: Right ventricular (RV pacing generates regional disparities in electrical activation and mechanical function (ventricular dyssynchrony. In contrast, left ventricular (LV or biventricular (BIV pacing can improve cardiac efficiency in the setting of ventricular dyssynchrony, constituting the rationale for cardiac resynchronization therapy (CRT. Animal models of ventricular dyssynchrony and CRT currently relay on large mammals which are expensive and not readily available to most researchers. We developed a methodology for double-site epicardial pacing in conscious rats. Here, following post-operative recovery, we compared the effects of various pacing modes on LV dyssynchrony in normal rats and in rats with ischemic cardiomyopathy. METHODS: Two bipolar electrodes were implanted in rats as follows: Group A (n = 6 right atrial (RA and RV sites; Group B (n = 7 RV and LV sites; Group C (n = 8 as in group B in combination with left coronary artery ligation. Electrodes were exteriorized through the back. Following post-operative recovery, two-dimensional transthoracic echocardiography was performed during pacing through the different electrodes. Segmental systolic circumferential strain (Ecc was used to evaluate LV dyssynchrony. RESULTS: In normal rats, RV pacing induced marked LV dyssynchrony compared to RA pacing or sinus rhythm, as measured by the standard deviation (SD of segmental time to peak Ecc, SD of peak Ecc, and the average delay between opposing ventricular segments. LV pacing and, to a greater extend BIV pacing diminished the LV dyssynchrony compared to RV pacing. In rats with extensive MI, the effects of LV and BIV pacing were markedly attenuated, and the response of individual animals was variable. CONCLUSIONS: Rodent cardiac pacing mimics important features seen in humans. This model may be developed as a simple new tool to study the pathophysiology of ventricular dyssynchrony and CRT.

  15. Molecular studies on pig cryptosporidiosis in Poland.

    Science.gov (United States)

    Rzeżutka, A; Kaupke, A; Kozyra, I; Pejsak, Z

    2014-01-01

    Cryptosporidium intestinal parasites have been detected in farmed pigs worldwide. Infections are usually asymptomatic with a low number of oocysts shed in pig feces. This makes the recognition of infection difficult or unsuccessful when microscopic methods are used. The aim of this study was molecular identification of Cryptosporidium species in pig herds raised in Poland with regard to the occurrence of zoonotic species. In total, 166 pig fecal samples were tested. The examined pigs were aged 1 to 20 weeks. Overall, 39 pig farms were monitored for parasite presence. The detection and identification of Cryptosporidium DNA was performed on the basis of PCR-RFLP and nucleotide sequence analysis of the amplified 18 SSU rRNA and COWP gene fragments. Infected animals were housed in 21 (53.8%) of the pig farms monitored. The presence of Cryptosporidum was confirmed in 46 (27.7%) samples of pig feces. Among positive fecal samples, 34 (29.3%) were collected from healthy animals, and 12 (24%) from diarrheic pigs. Most infected animals (42.1%) were 2 to 3 months old. The following parasite species were detected: C. scrofarum, C. suis and C. parvum. Indeed, asymptomatic infections caused by C. scrofarum were observed in the majority of the herds. Mixed infections caused by C. suis and C. scrofarum were not common; however, they were observed in 8.6% of the positive animals. C. parvum DNA was found only in one sample collected from a diarrheic pig. The application of molecular diagnostic tools allowed for detection and identification of Cryptosporidium species in pigs. The sporadic findings of C. parvum are subsequent evidence for the contribution of pigs in the transmission of cryptosporidiosis from animals to humans.

  16. Blastocystis tropism in the pig intestine.

    Science.gov (United States)

    Fayer, R; Elsasser, T; Gould, R; Solano, G; Urban, J; Santin, M

    2014-04-01

    Blastocystis has been reported in pig feces but the sites of development in the gastrointestinal tract are unknown. The present study was undertaken to determine predilection sites of Blastocystis in 11 naturally infected pigs examined at 20 weeks of age. At necropsy, feces and contents of the duodenum, jejunum, ileum, and cecum were examined by immunofluorescence (IFA) microscopy and PCR and tissues from these sites as well as the proximal and distal colon were processed for histology from pigs 1 to 5. Feces were examined by IFA microscopy, and segments from the jejunum and ileum were processed for histology from pigs 6 to 11. Multiple sections were cut from each tissue segment, and each was stained with the following: hematoxylin and eosin, polyclonal rabbit antibody to Blastocystis, and ParaFlor B monoclonal antibody to Blastocystis. Blastocystis was detected in feces of all 11 pigs by IFA microscopy and determined by PCR and gene sequencing to be subtype 5 for pigs 1-5. Blastocystis was also detected in the lumen contents removed from the cecum of pigs 1-5 examined by IFA microscopy and in the cecum of pigs 4 and 5 by PCR. Blastocystis was also observed in tissue sections from the jejunum of 7 of the 11 pigs, in the proximal and distal colon of pigs 1-5, and in the cecum of 4 of these 5 pigs but was not detected in the duodenum or ileum of any pigs. In tissue sections, Blastocystis was found primarily in the lumen usually associated with digested food debris, sometimes in close proximity or appearing to adhere to the epithelium, but no stages were found to penetrate the epithelium or the lamina propria.

  17. Spectrophotometric retinal oximetry in pigs

    DEFF Research Database (Denmark)

    Traustason, Sindri; Kiilgaard, Jens Folke; Karlsson, Robert

    2013-01-01

    PURPOSE: To assess the validity of spectrophotometric retinal oximetry, by comparison to blood gas analysis and intra-vitreal measurements of partial pressure of oxygen (pO2). METHODS: Female domestic pigs were used for all experiments (n=8). Oxygen fraction in inspired air was changed using...... a mixture of room air, pure oxygen and pure nitrogen, ranging from 5% to 100% oxygen. Femoral arterial blood gas analysis and retinal oximetry was performed at each level of inspiratory oxygen fraction. Retinal oximetry was performed using a commercial instrument, the Oxymap Retinal Oximeter T1 (Oxymap ehf......, Reykjavik, Iceland). The device simultaneously acquires images at two wavelengths (570 nm and 600 nm) and specialized software automatically detects retinal blood vessels. In three pigs, invasive pO2-measurements were performed after the initial non-invasive measurements. RESULTS: Comparison of femoral...

  18. Guinea pig model of tuberculosis

    Institute of Scientific and Technical Information of China (English)

    Pushpa Gupta; U.D.Gupta

    2009-01-01

    Animal models are being developed for testing different vaccine candidates as well as testing of new antituber-cular since a long time.Mice,guinea pigs and rabbits are animals which are frequently used.Though each model has got its merits as well as demerits and each of them differ from human tuberculosis in one aspect or the other but none of the model completely mimics the human disease.Out of the different animal species, guinea pig model is one of the better models as it is very sensitive to M.tuberculosis infection but it has certain limitations like paucity of immunological reagents.However,it is the best model for tuberculosis research.

  19. Gut health in the pig

    DEFF Research Database (Denmark)

    Pluske, J. R.; Hansen, Christian Fink; Payne, H. G.

    2007-01-01

    Gastrointestinal disturbances can cause large economic losses in the pig industry. Diseases and conditions of the gastrointestinal tract (GIT) that can cause economic loss have generally been controlled by the use of dietary (and or in the water) antimicrobial compounds, such as antibiotic feed a...... gastrointestinal 'health' requires consideration....... additives and (or) minerals such as zinc and copper. However the implementation of legislation in some parts of the world, for example the European Union, and a growing sentiment worldwide to reduce the use of dietary antimicrobial compounds, has caused a reassessment of measures to influence GIT 'health......' and caused enormous interest in alternative means to control diseases and conditions of the GIT. There are now available a wide array of products and strategies available to the pig industry that influence 'gut health'. The products in the market place are characterised predominately not only...

  20. 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.

  1. Radionuclide noninvasive evaluation of heart failure beyond left ventricular function assessment.

    Science.gov (United States)

    Flotats, Albert; Carrió, Ignasi

    2009-01-01

    The management of patients with heart failure (HF) is challenging and requires the integration of clinical skills and accurate ancillary tests for the correct diagnosis and estimation of individual prognosis. Although the basic characterization of patients with HF is supported primarily by echocardiographic assessment of the left ventricular function, other noninvasive imaging procedures are being developed, including those involved in the processes of myocardial perfusion, metabolism, cellular injury, intersticial dysregulation, and neurohormonal receptor function. Nuclear techniques for molecular imaging of the myocardium may provide valuable insights into the pathophysiology, severity, management (medical/mechanical/surgical), response to treatment, and prognosis of HF patients. This will permit individualized management decisions and hopefully facilitate better clinical outcomes for patients with HF.

  2. Peripartum heart failure caused by left ventricular diastolic dysfunction: a case report.

    Science.gov (United States)

    Kakogawa, Jun; Nako, Takafumi; Igarashi, Suguru; Nakamura, Shin; Tanaka, Mamoru

    2014-08-01

    Peripartum cardiomyopathy is a rare but potentially life-threatening condition. The current definition of peripartum cardiomyopathy only includes patients with systolic dysfunction. We describe a 25-year-old nulligravid patient with heart failure, i.e. left ventricular diastolic dysfunction with preserved systolic dysfunction during the third trimester of pregnancy. She complained of dyspnea and was referred to our hospital at 31 weeks of gestation. The patient met the clinical criteria for peripartum cardiomyopathy with the exception of systolic dysfunction. Brain-type natriuretic peptide levels peaked at 1447 pg/dL. The patient responded to therapy for heart failure and showed resolution of her diastolic dysfunction by 1 month postpartum. The case demonstrated the important role of diastolic dysfunction in peripartum heart failure and the possibility of clarifying the pathophysiology of peripartum cardiomyopathy by evaluating diastolic function. Further investigations are needed to provide evidence regarding the clinical role of diastolic dysfunction in peripartum heart failure.

  3. Epidemiology of left ventricular hypertrophy in hypertension: implications for the clinic.

    Science.gov (United States)

    Cramariuc, Dana; Gerdts, Eva

    2016-08-01

    Left ventricular hypertrophy (LVH) is a common complication to hypertension, indicating the presence of hypertensive heart disease, which puts the patient at a very high risk for subsequent clinical cardiovascular events like sudden cardiac death, stroke, myocardial infarction and heart failure. The epidemiology of LVH has changed in recent years as a consequence of the development of new diagnostic tools and demographic changes in hypertensive populations. Expert commentary: In individual hypertensive patients, the presence and type of LVH and associated systolic and diastolic myocardial dysfunction is modified by the co-presence of other cardiovascular risk factors and comorbidities and as well as activation of the reninangiotensin-aldosterone system and other molecular mechanisms involved in LVH pathophysiology. The purpose of this review is to give a clinical update on LVH in hypertension.

  4. Myocardial infarction and transient ventricular dysfunction in an adolescent with sickle cell disease.

    Science.gov (United States)

    Deymann, Andreas J; Goertz, Kenneth K

    2003-02-01

    We report a case of an adolescent who had sickle cell disease and previous evidence of myocardial damage and presented with abdominal pain and rapid progression to cardiogenic shock and subsequent development of myocardial infarction. To our knowledge, this represents only the second report of a case of acute myocardial ischemia and subsequent infarction resulting transient ventricular dysfunction reported in a child with sickle cell disease successfully treated with exchange transfusion. The pathophysiology of this complication remains unclear, and cardiac complications may remain undetected as lung, bone, and brain infarcts are more common and the pain associated with sickle cell crisis may mask the ischemic symptoms. Multiple factors may contribute to ischemia in addition to the presence of a vaso-occlusive crisis or infection. Acute or chronic myocardial ischemia are probably more prevalent than currently known.

  5. [Left-ventricular hypertrophy as a cardiac risk factor: role of the renin-angiotensin-aldosterone system].

    Science.gov (United States)

    Erne, P

    1996-02-20

    Left-ventricular hypertrophy is the result of cardiac adaptation to global or regional overstress and represents an important cardiovascular risk factor, increasing the risk for development of congestive heart failure and incidence of sudden death. This review describes the pathophysiological and biochemical mechanisms involved in the development of left-ventricular hypertrophy and cardiac fibrosis with particular emphasis on the role of angiotensin II and aldosterone. Central to the cascade of cardiac fibrosis is the increased production or reduced degradation of collagen proteins in fibroblasts. Collagen proteins are proteins needed for the alignment of cellular compartments and the development of forces, contraction and relaxation of the heart. If overexpressed, an important rise of wall stiffness is observed in addition to a reduced capacity to provide oxygen to the cardiac tissue. This latter explains why in areas of histologically hypertrophied heart muscle atrophied muscle cells are observed. The characterization of the second-messenger systems involved in the regulation of cardiac cells as well as the identification of angiotensin-II receptor subtype and angiotensin IV is described. Both of these receptors are present on cardiac fibroblasts and stimulate these to collagen production, which can be inhibited by antagonists or the generation of angiotensin II by ACE inhibitors. In some forms of left-ventricular hypertrophy and in patients with congestive heart failure in addition to elevated angiotensin-II levels, increased aldosterone levels are observed. Aldosterone raises upon stimulation by angiotensin II and upon reduction of angiotensin-II generation subsequent to ACE inhibition through an escape mechanism. The contribution of aldosterone to left-ventricular hypertrophy and cardiac fibrosis can be prevented and reduced by the administration of its antagonist, spironolactone. Further and larger clinical trials are needed and in progress to evaluate if the

  6. Analysis of flow dynamics in right ventricular outflow tract.

    Science.gov (United States)

    Berdajs, Denis A; Mosbahi, Selim; Charbonnier, Dominique; Hullin, Roger; von Segesser, Ludwig K

    2015-07-01

    The mechanism behind early graft failure after right ventricular outflow tract (RVOT) reconstruction is not fully understood. Our aim was to establish a three-dimensional computational fluid dynamics (CFD) model of RVOT to investigate the hemodynamic conditions that may trigger the development of intimal hyperplasia and arteriosclerosis. Pressure, flow, and diameter at the RVOT, pulmonary artery (PA), bifurcation of the PA, and left and right PAs were measured in 10 normal pigs with a mean weight of 24.8 ± 0.78 kg. Data obtained from the experimental scenario were used for CFD simulation of pressure, flow, and shear stress profile from the RVOT to the left and right PAs. Using experimental data, a CFD model was obtained for 2.0 and 2.5-L/min pulsatile inflow profiles. In both velocity profiles, time and space averaged in the low-shear stress profile range from 0-6.0 Pa at the pulmonary trunk, its bifurcation, and at the openings of both PAs. These low-shear stress areas were accompanied to high-pressure regions 14.0-20.0 mm Hg (1866.2-2666 Pa). Flow analysis revealed a turbulent flow at the PA bifurcation and ostia of both PAs. Identified local low-shear stress, high pressure, and turbulent flow correspond to a well-defined trigger pattern for the development of intimal hyperplasia and arteriosclerosis. As such, this real-time three-dimensional CFD model may in the future serve as a tool for the planning of RVOT reconstruction, its analysis, and prediction of outcome. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. WILD PIG ATTACKS ON HUMANS

    Energy Technology Data Exchange (ETDEWEB)

    Mayer, J.

    2013-04-12

    Attacks on humans by wild pigs (Sus scrofa) have been documented since ancient times. However, studies characterizing these incidents are lacking. In an effort to better understand this phenomenon, information was collected from 412 wild pig attacks on humans. Similar to studies of large predator attacks on humans, data came from a variety of sources. The various attacks compiled occurred in seven zoogeographic realms. Most attacks occurred within the species native range, and specifically in rural areas. The occurrence was highest during the winter months and daylight hours. Most happened under non-hunting circumstances and appeared to be unprovoked. Wounded animals were the chief cause of these attacks in hunting situations. The animals involved were typically solitary, male and large in size. The fate of the wild pigs involved in these attacks varied depending upon the circumstances, however, most escaped uninjured. Most human victims were adult males traveling on foot and alone. The most frequent outcome for these victims was physical contact/mauling. The severity of resulting injuries ranged from minor to fatal. Most of the mauled victims had injuries to only one part of their bodies, with legs/feet being the most frequent body part injured. Injuries were primarily in the form of lacerations and punctures. Fatalities were typically due to blood loss. In some cases, serious infections or toxemia resulted from the injuries. Other species (i.e., pets and livestock) were also accompanying some of the humans during these attacks. The fates of these animals varied from escaping uninjured to being killed. Frequency data on both non-hunting and hunting incidents of wild pig attacks on humans at the Savannah River Site, South Carolina, showed quantitatively that such incidents are rare.

  8. Fermented liquid feed for pigs

    OpenAIRE

    Missotten, Joris; Michiels, Joris; Ovyn, Anneke; De Smet, Stefaan; Dierick, Noël

    2010-01-01

    Since the announcement of the ban on the use of antibiotics as antimicrobial growth promoters in the feed of pigs in 2006 the investigation towards alternative feed additives has augmented considerably. Although fermented liquid feed is not an additive, but a feeding strategy, the experimental work examining its possible advantages also saw a rise. The use of fermented liquid feed (FLF) has two main advantages, namely that the simultaneous provision of feed and water may result in an alleviat...

  9. Dynamic regulation of atrial coronary blood flow in healthy adult pigs.

    Science.gov (United States)

    van Bragt, Kelly A; Nasrallah, Hussein M; Kuiper, Marion; van Hunnik, Arne; Kuijpers, Nico H L; Schotten, Ulrich; Verheule, Sander

    2015-05-01

    There are several indications for a mismatch between atrial oxygen supply and demand during atrial fibrillation (AF), but atrial coronary flow regulation has not been investigated extensively. The purpose of this study was to characterize the dynamic regulation of atrial coronary flow in pigs. In anesthetized open-chest pigs, Doppler flow probes were placed around left atrial (LA) and left ventricular (LV) branches of the circumflex artery. Pressures and work indices were measured simultaneously. Systolic and diastolic flow contribution, flow response kinetics, and relationship between pressures, work, and flow were investigated during sinus rhythm, atrial pacing, and acute AF. During atrial systole, LA flow decreased. Only 2% of total LA flow occurred during atrial systole. Pacing with 2:1 AV block and infusion of acetylcholine revealed that atrial contraction itself impeded atrial coronary flow. The response to sudden changes in heart rate was slower in LA compared to LV. Both LA and LV vascular conductance were positively correlated with work. After the cessation of acute AF, the LA showed a more pronounced phase of supranormal vascular conductance than the LV, indicating a period of atrial reactive hyperemia. In healthy adult pigs, atrial coronary flow is impeded by atrial contraction. Although atrial coronary blood flow is positively correlated with atrial external work, it reacts more slowly to changes in rate than ventricular flow. The occurrence of a pronounced hyperemic phase after acute AF supports the notion of a significant supply-demand mismatch during AF. Copyright © 2015 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

  10. A consumer study of entire male pigs

    DEFF Research Database (Denmark)

    Godt, Jannik; Kristensen, Kai; Poulsen, Carsten Stig;

    1996-01-01

    Former studies of the unpleasant odour of meat from certain uncastrated male pigs have been based mainly on evaluations made by trained sensory panellists. This study analyses the effect of the two dominating male pig odour components, skatole and androstenone, on the evaluation of eating quality...... made in-home by consumers, thus bringing the analysis out of the laboratory and into the market place. The vast majority of the population of uncastrated male pigs have low concentrations of skatole and androstenone. The cutlets that were evaluated in this study were selected from uncastrated male pigs...

  11. Atrioventricular Left Ventricular Apical Pacing Improves Haemodynamic, Rotational, and Deformation Variables in Comparison to Pacing at the Lateral Wall in Intact Myocardium: Experimental Study

    Directory of Open Access Journals (Sweden)

    Savvas Toumanidis

    2014-01-01

    Full Text Available Aim. To assess the effect on left ventricular (LV function of atrioventricular (AV and ventricular pacing at the LV apical or lateral wall and to compare the normal torsional and deformation pattern of the intact LV myocardium with those created by the aforementioned LV pacing modes and sites. Methods. Experiments were conducted in pigs (n=21 with normal LV function to investigate the acute hemodynamic effects of epicardial AV and ventricular LV pacing at the LV apical or lateral wall. Torsional and deformation indices of LV function were assessed using speckle tracking echocardiography. Results. AV pacing at the apex revealed a significant reduction in the radial strain of the base (P<0.03, without affecting significantly the ejection fraction and the LV torsion or twist. In contrast, AV pacing at the lateral wall produced, in addition to the reduction of the radial strain of the base (P<0.01, significant reduction of the circumferential and the radial strain of the apex (both P<0.01 as well as of the ejection fraction (P<0.002 and twist (P<0.05. Conclusions. In pig hearts with intact myocardium, LV function is maintained at sinus rhythm level when AV pacing is performed at the LV apex.

  12. Energy use in pig farming

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-02-15

    This guide presents benchmark data on 'typical' and 'good practice' levels of energy consumption for pig farms in the UK. Benchmarks are valuable because they allow producers to compare their performance with other similar businesses. In addition, they also provide two other useful functions: They allow routine assessments to be made that show progress against a benchmark. Such appraisals are not restricted to year-on-year evaluations as they can be carried out quarterly, monthly or even weekly to track progress on a more frequent basis Opportunity assessments can be carried out. For example, if a facility is to be modified or upgraded, the effect of the change can be determined. Throughout this guide, the benchmarks and information are based on methods and techniques that minimise energy consumption whilst maintaining pig performance at an economically acceptable level. Pig farming in the UK is a complex and diverse business with a variety of facilities being used for each stage of production. Therefore, in order to give realistic guidelines, production has been broken down into several key areas to illustrate typical performance benchmarks. These production areas are: farrowing accommodation; weaning accommodation; finisher accommodation; feeding system; and waste handling. The guide has a detailed breakdown with graphs and data analysis.

  13. Left Ventricular Involvement in Arrhythmogenic Right Ventricular Dysplasia/Cardiomyopathy Assessed by Echocardiography Predicts Adverse Clinical Outcome

    NARCIS (Netherlands)

    Mast, Thomas P.; Teske, Arco J.; van der Heijden, Jeroen F.; Groeneweg, Judith A.; Te Riele, Anneline S J M; Velthuis, Birgitta K.; Hauer, RNW; Doevendans, Pieter A.; Cramer, Maarten J.

    2015-01-01

    Background Among studies describing the phenotype of arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C), significant discrepancy exists regarding the extent and impact of left ventricular (LV) involvement. The capability of conventional and new quantitative echocardiographic techniqu

  14. 21 CFR 870.3545 - Ventricular bypass (assist) device.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ventricular bypass (assist) device. 870.3545... (CONTINUED) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Prosthetic Devices § 870.3545 Ventricular bypass (assist) device. (a) Identification. A ventricular bypass (assist) device is a device that...

  15. The relation between bradycardic dyssynchronous ventricular activation, remodeling and arrhythmogenesis

    NARCIS (Netherlands)

    Dunnink, A

    2016-01-01

    Sudden cardiac death (SCD) is a common cause of death and its incidence continues to rise. The occurrence of SCD is mainly due to development of malignant ventricular arrhythmias such as ventricular tachycardia or ventricular fibrillation. The underlying cause of SCD is almost always a complex

  16. The relation between bradycardic dyssynchronous ventricular activation, remodeling and arrhythmogenesis

    NARCIS (Netherlands)

    Dunnink, A

    2016-01-01

    Sudden cardiac death (SCD) is a common cause of death and its incidence continues to rise. The occurrence of SCD is mainly due to development of malignant ventricular arrhythmias such as ventricular tachycardia or ventricular fibrillation. The underlying cause of SCD is almost always a complex remod

  17. Analysis of normal and denerved laryngeal vocalization in guinea pigs (Cavia porcellus).

    Science.gov (United States)

    Arch-Tirado, Emilio; Verduzco-Mendoza, Antonio; Taboada-Picazo, Verónica; Mota-Rojas, Daniel; Alonso-Spilsbury, Maria de Lourdes; Alfaro-Rodríguez, Alfonso

    2009-01-01

    Paralysis of the left vocal chord is frequent in human clinical practice; because of its anatomic similarity with human, the guinea pig might be a suitable biological model to analyze the phoniatric behavior in denerved animals. Forty newborn guinea pigs were used (20 control and 20 experimental); an incision was made in the ventricular region with the animals under general anesthesia over the middle line of the neck, until the lower left laryngeal nerve was found, the same was secured with alligator clips so that afterward a two-part dissection could be performed and the middle section could be removed (1cm) from the nerve endings (distal and proximal) before they were separated from the laryngeal structure. After recovery from surgery, vocal emissions were recorded in solitary for 6 minutes. The animals that had nerves removed showed an increase in fundamental vocalization frequency compared with the controls. F test was carried out (P=0.05) and no significant difference was found. When analyzing functional recovery, we found that the guinea pigs compensated vocal emissions at 20 days. With regard to the unilateral paralysis, the motility was frequently compensated by the healthy vocal chord, improving voice emission, and loss of air inhalation.

  18. Cardiac actions of phencyclidine in isolated guinea pig and rat heart: possible involvement of slow channels

    Energy Technology Data Exchange (ETDEWEB)

    Temma, K.; Akera, T.; Ng, Y.C.

    1985-03-01

    The mechanisms responsible for the positive inotropic effect of phencyclidine were studied in isolated preparations of guinea pig and rat heart. In electrically paced left atrial muscle preparations, phencyclidine increased the force of contraction; rat heart muscle preparations were more sensitive than guinea pig heart muscle preparations. The positive inotropic effect of phencyclidine was not significantly reduced by a combination of phentolamine and nadolol; however, the effect was competitively blocked by verapamil in the presence of phentolamine and nadolol. Inhibition of the outward K+ current by tetraethylammonium chloride also produced a positive inotropic effect; however, the effect of tetraethylammonium was reduced by phentolamine and nadolol, and was almost insensitive to verapamil. The inotropic effect of phencyclidine was associated with a marked prolongation of the action potential duration and a decrease in maximal upstroke velocity of the action potential, with no change in the resting membrane potential. The specific (/sup 3/H)phencyclidine binding observed with membrane preparations from guinea pig ventricular muscle was saturable with a single class of high-affinity binding site. This binding was inhibited by verapamil, diltiazem, or nitrendipine, but not by ryanodine or tetrodotoxin. These results suggest that the positive inotropic effect of phencyclidine results from enhanced Ca/sup 2 +/ influx via slow channels, either by stimulation of the channels or secondary to inhibition of outward K/sup +/ currents.

  19. Microvascular dysfunction in nonfailing arrhythmogenic right ventricular cardiomyopathy

    Energy Technology Data Exchange (ETDEWEB)

    Paul, Matthias [University Hospital Muenster, Department of Cardiology and Angiology, Muenster (Germany); University Hospital Muenster, Institute for Genetics of Heart Diseases, Muenster (Germany); Rahbar, Kambiz; Kies, Peter; Schober, Otmar [University Hospital Muenster, Department of Nuclear Medicine, Muenster (Germany); Gerss, Joachim [University of Muenster, Institute of Biostatistics and Clinical Research, Muenster (Germany); Schaefers, Klaus; Schaefers, Michael [University of Muenster, European Institute for Molecular Imaging - EIMI, Muenster (Germany); Breithardt, Guenter [University Hospital Muenster, Department of Cardiology and Angiology, Muenster (Germany); Schulze-Bahr, Eric [University Hospital Muenster, Institute for Genetics of Heart Diseases, Muenster (Germany); Wichter, Thomas [Marienhospital Osnabrueck, Department of Cardiology, Niels-Stensen-Kliniken, Osnabrueck (Germany)

    2012-03-15

    Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a nonischaemic cardiomyopathy and leading cause of sudden death in the young. It has been shown that microvascular dysfunction reflected by an impaired myocardial blood flow (MBF) response to stress is present in patients with other forms of nonischaemic cardiomyopathy, e.g. dilated cardiomyopathy, and that the reduced MBF may be related to a poor prognosis. Therefore, we quantified MBF, coronary flow reserve and coronary vascular resistance in patients with nonfailing ARVC using H{sub 2}{sup 15} O and PET. In ten male patients with ARVC (mean age 49 {+-} 14 years), MBF was quantified at rest and during adenosine-induced hyperaemia using H{sub 2}{sup 15} O PET. Results were compared with those obtained in 20 age-matched healthy male control subjects (mean age 46 {+-} 14 years). Resting MBF was not significantly different between patients with ARVC and controls (MBF{sub rest} 1.19 {+-} 0.29 vs. 1.12 {+-} 0.20 ml/min/ml). However, hyperaemic MBF was significantly lower in patients with ARVC than in controls (2.60 {+-} 0.96 vs. 3.68 {+-} 0.84 ml/min/ml; p = 0.005). Consequently, patients with ARVC had a significantly lower coronary flow reserve than control subjects (2.41 {+-} 1.34 vs. 3.39 {+-} 0.93; p = 0.030). In addition, hyperaemic coronary vascular resistance was increased in patients with ARVC (36.79 {+-} 12.91 vs. 26.31 {+-} 6.49 mmHg x ml{sup -1} x min x ml; p = 0.007), but was found to be unchanged at rest. In this small well-characterized cohort of patients with nonfailing ARVC, we found a significantly reduced hyperaemic MBF and increased coronary vascular resistance. Further studies are necessary to corroborate this potential new functional aspect of the pathophysiological mechanisms underlying ARVC. (orig.)

  20. Association between the kinin-forming system and cardiovascular pathophysiology

    Institute of Scientific and Technical Information of China (English)

    Jagdish Narain Sharma

    2012-01-01

    All the components of the kallikrein-kinin system are located in the cardiac muscle, and its deficiency may lead to cardiac dysfunction. In recent years, numerous observations obtained from clinical and experimental models of diabetes, hypertension, cardiac failure, ischaemia, myocardial infarction and left ventricular hypertrophy, have suggested that the reduced activity of the local kallikrein-kinin system may be instrumental for the induction of cardiovascular -related diseases. The cardioprotective property of the angiotensin converting enzyme inhibitors is primarily mediated via kinin releasing pathway, which may cause regression of the left ventricular hypertrophy in hypertensive situations. The ability of kallikrein gene delivery to produce a wide spectrum of beneficial effects makes it an excellent candidate in treating hypertension, cardiovascular and renal diseases. In addition, stable kinin agonists may also be available in the future as therapeutic agents for cardiovascular and renal disorders.

  1. Estimation of the left ventricular relaxation time constant tau requires consideration of the pressure asymptote.

    Science.gov (United States)

    Langer, S F J; Habazettl, H; Kuebler, W M; Pries, A R

    2005-01-01

    The left ventricular isovolumic pressure decay, obtained by cardiac catheterization, is widely characterized by the time constant tau of the exponential regression p(t)=Pomega+(P0-Pomega)exp(-t/tau). However, several authors prefer to prefix Pomega=0 instead of coestimating the pressure asymptote empirically; others present tau values estimated by both methods that often lead to discordant results and interpretation of lusitropic changes. The present study aims to clarify the relations between the tau estimates from both methods and to decide for the more reliable estimate. The effect of presetting a zero asymptote on the tau estimate was investigated mathematically and empirically, based on left ventricular pressure decay data from isolated ejecting rat and guinea pig hearts at different preload and during spontaneous decrease of cardiac function. Estimating tau with preset Pomega=0 always yields smaller values than the regression with empirically estimated asymptote if the latter is negative and vice versa. The sequences of tau estimates from both methods can therefore proceed in reverse direction if tau and Pomega change in opposite directions between the measurements. This is exemplified by data obtained during an increasing preload in spontaneously depressed isolated hearts. The estimation of the time constant of isovolumic pressure fall with a preset zero asymptote is heavily biased and cannot be used for comparing the lusitropic state of the heart in hemodynamic conditions with considerably altered pressure asymptotes.

  2. Direct cardiac potential trigger for chronic control of a ventricular assist device.

    Science.gov (United States)

    Kitamura, M; Hanzawa, K; Aoki, K; Saitoh, M; Hayashi, J

    2001-01-01

    As a new trigger method for chronic drive control of a ventricular assist device (VAD), a direct cardiac potential trigger was assessed under various conditions in a chronic experimental model. A pneumatic pulsatile VAD was implanted as circulatory support between the left ventricular apex and the ascending aorta in 12 adult pigs. Hemodynamic parameters and pump output were continuously monitored. Two tips of a bipolar electrode were set on the RV anterior wall and the LV posterior wall for recording direct cardiac potential. Counterpulsation drive of the VAD was applied by using the R wave in a standard electrocardiogram (ECG) or the direct cardiac potential as an ECG trigger. As special conditions, various artifacts on ECG, electromusculogram, arrhythmia, irregular ventilation, and passive vibration (simulation of exercise) were set for assessing the ECG trigger modes. Artifacts of irregular ventilation and passive vibration made the drive control poor using a standard ECG trigger. In contrast, the direct cardiac potential trigger maintained the counterpulsation control of the VAD well in all conditions of this study, and was a safe and reliable support for the native heart. It also supported animals for up to 48 hours after operation. The above results suggested that the direct cardiac potential trigger might be useful for monitoring native heart beats and adjusting the support cycle to the native heart cycle as a chronic control method for various VADs.

  3. Diastolic Left Ventricular Dysfunction : A Clinical Appraisal

    NARCIS (Netherlands)

    Bronzwaer, J.G.F.

    2003-01-01

    Diastolic left ventricular (LV) distensibility is determined by the material properties of the LV wall and by LV geometry (i.e., LV shape, LV volume and LV wall thickness). These material properties are influenced both by the physical structure of the LV myocardium and by the dynamic process of myoc

  4. 3-Dimensional Right Ventricular Volume Assessment

    NARCIS (Netherlands)

    Jainandunsing, Jayant S.; Matyal, Robina; Shahul, Sajid S.; Wang, Angela; Woltersom, Bozena; Mahmood, Feroze

    Purpose: The purpose of this review was to evaluate new computer software available for 3-dimensional right ventricular (RV) volume estimation. Description: Based on 2-dimensional echocardiography, various algorithms have been used for RV volume estimation. These are complex, time-consuming

  5. Catheter ablation of parahisian premature ventricular complex.

    Science.gov (United States)

    Kim, Jun; Kim, Jeong Su; Park, Yong Hyun; Kim, June Hong; Chun, Kook Jin

    2011-12-01

    Catheter ablation is performed in selected patients with a symptomatic premature ventricular complex (PVC) or PVC-induced cardiomyopathy. Ablation of PVC from the His region has a high risk of inducing a complete atrioventricular block. Here we report successful catheter ablation of a parahisian PVC in a 63-year-old man.

  6. New test for arrhythmogenic right ventricular cardiomyopathy

    NARCIS (Netherlands)

    van Tintelen, J. Peter; Hauer, Richard N. W.

    Arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) is challenging to diagnose because of nonspecific findings, particularly in the early phases of the disease. clinical diagnosis is made on the basis of several criteria, but these lack sensitivity. Asimaki et al. suggest that

  7. Congestive cardiomyopathy and left ventricular thrombus.

    Science.gov (United States)

    Gould, L; Gopalaswamy, C; Chandy, F; Kim, B S

    1983-07-01

    A left ventricular thrombus was detected by echocardiography in a 54-year-old man with congestive cardiomyopathy. With the use of anticoagulants, the thrombus completely disappeared. Patients with congestive cardiomyopathy who are at high risk for thrombus formation should be screened with two-dimensional echocardiography. If a thrombus is recognized, anticoagulation therapy can then be instituted.

  8. Diagnosis and management of ventricular dysphonia.

    Science.gov (United States)

    Von Hake, C P; Ganzman, I P; Mauer, T P

    1989-02-01

    Ventricular phonation may develop on a functional level, or it may occur as an alternative voice for the patient who has an organic disease of the true vocal folds. Three cases that represent iatrogenic, traumatic, and neurologic forms of the disorder are reported. Diagnosis, treatment, and guidelines for follow-up speech therapy are discussed.

  9. Diastolic Left Ventricular Dysfunction : A Clinical Appraisal

    NARCIS (Netherlands)

    Bronzwaer, J.G.F.

    2003-01-01

    Diastolic left ventricular (LV) distensibility is determined by the material properties of the LV wall and by LV geometry (i.e., LV shape, LV volume and LV wall thickness). These material properties are influenced both by the physical structure of the LV myocardium and by the dynamic process of

  10. World Health Organization Group I Pulmonary Hypertension: Epidemiology and Pathophysiology.

    Science.gov (United States)

    Prins, Kurt W; Thenappan, Thenappan

    2016-08-01

    Pulmonary arterial hypertension (PAH) is a debilitating disease characterized by pathologic remodeling of the resistance pulmonary arteries, ultimately leading to right ventricular (RV) failure and death. In this article we discuss the definition of PAH, the initial epidemiology based on the National Institutes of Health Registry, and the updated epidemiology gleaned from contemporary registries, pathogenesis of pulmonary vascular dysfunction and proliferation, and RV failure in PAH. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Ventricular tachycardia as a first manifestation of right ventricular myxoma--a case presentation.

    Science.gov (United States)

    Badui, E; Cruz, H; Almazan, A; Enciso, R; Soberanis, N; Garcia, R

    1991-12-01

    The authors present a case of a thirty-nine-year-old white man in good health who developed episodes of ventricular tachycardia as a first manifestation of a right ventricular myxoma, which was diagnosed by two-dimensional echocardiogram and then resected with no complications and total disappearance of the cardiac arrhythmia. After reviewing the literature they consider the present case as a rare manifestation of an infrequent location of an uncommon disease.

  12. Effects of Long-term Right Ventricular Apical Pacing on Left Ventricular Remodeling and Cardiac Function

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Objective: To investigate the impacts of long-term right ventricular apical pacing on the ventricular remodeling and cardiac functions of patients with high-grade and third-degree atrioventricular blockage with normal heart structures and cardiac functions. In addition, we provide many evidences for choosing an optimal electrode implantation site.Methods: Study participants included patients who were admitted for pacemaker replacements and revisited for examinations of implanted pacemakers at outpatient. Pa...

  13. Angiographic left ventricular wall motion score to predict arrhythmia recurrence in patients with sustained ventricular tachycardia or fibrillation

    NARCIS (Netherlands)

    Wiesfeld, ACP; Crijns, HJGM; VandenBroek, SAJ; Landsman, MLJ; Hillege, HL; vanGilst, WH; Lie, KI

    1996-01-01

    Methods Sixty-nine patients with sustained ventricular tachyarrhythmias were followed up to evaluate the predictive value of functional capacity (i.e. New York Heart Association class and peak oxygen consumption) and resting left ventricular function (i.e. radionuclide left ventricular ejection frac

  14. Epicardial and endocardial mapping determine most successful site of ablation for ventricular tachyarrhythmias originating from left ventricular summit.

    Science.gov (United States)

    Iijima, Kenichi; Chinushi, Masaomi; Furushima, Hiroshi; Aizawa, Yoshifusa

    2012-06-01

    A 34-year-old woman presented with idiopathic premature ventricular complex (PVC) and ventricular tachycardia (VT) originating from the area called the left ventricular summit. Radiofrequency (RF) application both through the coronary sinus and to the epicardial surface transiently suppressed the VT/PVC. Radiofrequency with sufficient energy was only applicable from the endocardial site, and the VT/PVC was successfully eliminated.

  15. Myocardial structural, contractile and electrophysiological changes in the guinea-pig heart failure model induced by chronic sympathetic activation

    DEFF Research Database (Denmark)

    Soltysinska, Ewa; Osadchiy, Oleg; Olesen, Søren-Peter

    2011-01-01

    potential, effective refractory period and QT interval, an upward shift of the electrical restitution curve determined over a wide range of diastolic intervals, and reduced maximal restitution slope. The physiological right ventricular-to-LV difference in action potential duration was eliminated in ISO...... whether sustained adrenergic activation may produce a clinically relevant heart failure phenotype in the guinea-pig, an animal species whose ventricular action potential shape and restitution properties resemble those determined in humans. Isoprenaline (ISO), a ß-adrenoceptor agonist, was infused...... pressure-volume and stress-strain relationships assessed in isolated, perfused heart preparations), reduced contractile reserve in the presence of acute ß-adrenoceptor stimulation, and pulmonary oedema (increased lung weights). These changes were associated with prolongation of LV epicardial action...

  16. Cavopulmonary Anastomosis in a Patient With Arrhythmogenic Right Ventricular Cardiomyopathy With Severe Right Ventricular Dysfunction.

    Science.gov (United States)

    Vaidyanathan, Swaminathan; Kothandam, Sivakumar; Kumar, Rajesh; Indrajith, Sujatha Desai; Agarwal, Ravi

    2017-01-01

    A 26-year-old lady presented with exertional dyspnea, palpitations, central cyanosis, and oxygen saturations of 80% in room air. Her electrocardiogram, echocardiogram, and cardiac magnetic resonance were diagnostic of arrhythmogenic right ventricular dysplasia. There was no documented ventricular arrhythmia or syncopal episodes and Holter recordings were repeatedly normal. Cardiac hemodynamics showed right to left shunt through atrial septal defect, low pulmonary blood flow, normal atrial pressures, and minimally elevated right ventricular end-diastolic pressures. Since her presenting symptoms and cyanosis were attributed to reduced pulmonary blood flow, she underwent off-pump cavopulmonary anastomosis between right superior vena cava and right pulmonary artery. As we intended to avoid the adverse effect of extracorporeal circulation on the myocardial function and pulmonary vasculature, we did not attempt to reduce the size of the atrial septal defect. Her postoperative period was uneventful; oxygen saturation improved to 89% with significant improvement in effort tolerance. At 18-month follow-up, there were no ventricular arrhythmias on surveillance. The clinical presentation of this disease may vary from serious arrhythmias warranting defibrillators and electrical ablations at one end to right ventricular pump failure warranting cardiomyoplasty or right ventricular exclusion procedures at the other end. However, when the presentation was unusual with severe cyanosis through a stretched foramen ovale leading to reduced pulmonary blood flows, Glenn shunt served as a good palliation and should be considered as one of the options in such patients.

  17. Impact of hypokalemia on electromechanical window, excitation wavelength and repolarization gradients in guinea-pig and rabbit hearts.

    Science.gov (United States)

    Osadchii, Oleg E

    2014-01-01

    Normal hearts exhibit a positive time difference between the end of ventricular contraction and the end of QT interval, which is referred to as the electromechanical (EM) window. Drug-induced prolongation of repolarization may lead to the negative EM window, which was proposed to be a novel proarrhythmic marker. This study examined whether abnormal changes in the EM window may account for arrhythmogenic effects produced by hypokalemia. Left ventricular pressure, electrocardiogram, and epicardial monophasic action potentials were recorded in perfused hearts from guinea-pig and rabbit. Hypokalemia (2.5 mM K(+)) was found to prolong repolarization, reduce the EM window, and promote tachyarrhythmia. Nevertheless, during both regular pacing and extrasystolic excitation, the increased QT interval invariably remained shorter than the duration of mechanical systole, thus yielding positive EM window values. Hypokalemia-induced arrhythmogenicity was associated with slowed ventricular conduction, and shortened effective refractory periods, which translated to a reduced excitation wavelength index. Hypokalemia also evoked non-uniform prolongation of action potential duration in distinct epicardial regions, which resulted in increased spatial variability in the repolarization time. These findings suggest that arrhythmogenic effects of hypokalemia are not accounted for by the negative EM window, and are rather attributed to abnormal changes in ventricular conduction times, refractoriness, excitation wavelength, and spatial repolarization gradients.

  18. Impact of hypokalemia on electromechanical window, excitation wavelength and repolarization gradients in guinea-pig and rabbit hearts.

    Directory of Open Access Journals (Sweden)

    Oleg E Osadchii

    Full Text Available Normal hearts exhibit a positive time difference between the end of ventricular contraction and the end of QT interval, which is referred to as the electromechanical (EM window. Drug-induced prolongation of repolarization may lead to the negative EM window, which was proposed to be a novel proarrhythmic marker. This study examined whether abnormal changes in the EM window may account for arrhythmogenic effects produced by hypokalemia. Left ventricular pressure, electrocardiogram, and epicardial monophasic action potentials were recorded in perfused hearts from guinea-pig and rabbit. Hypokalemia (2.5 mM K(+ was found to prolong repolarization, reduce the EM window, and promote tachyarrhythmia. Nevertheless, during both regular pacing and extrasystolic excitation, the increased QT interval invariably remained shorter than the duration of mechanical systole, thus yielding positive EM window values. Hypokalemia-induced arrhythmogenicity was associated with slowed ventricular conduction, and shortened effective refractory periods, which translated to a reduced excitation wavelength index. Hypokalemia also evoked non-uniform prolongation of action potential duration in distinct epicardial regions, which resulted in increased spatial variability in the repolarization time. These findings suggest that arrhythmogenic effects of hypokalemia are not accounted for by the negative EM window, and are rather attributed to abnormal changes in ventricular conduction times, refractoriness, excitation wavelength, and spatial repolarization gradients.

  19. Left ventricular twist is load-dependent as shown in a large animal model with controlled cardiac load

    Directory of Open Access Journals (Sweden)

    A’roch Roman

    2012-06-01

    Full Text Available Abstract Background Left ventricular rotation and twist can be assessed noninvasively by speckle tracking echocardiography. We sought to characterize the effects of acute load change and change in inotropic state on rotation parameters as a measure of left ventricular (LV contractility. Methods Seven anesthetised juvenile pigs were studied, using direct measurement of left ventricular pressure and volume and simultaneous transthoracic echocardiography. Transient inflation of an inferior vena cava balloon (IVCB catheter produced controlled load reduction. First and last beats in the sequence of eight were analysed with speckle tracking (STE during the load alteration and analysed for change in rotation/twist during controlled load alteration at same contractile status. Two pharmacological inotropic interventions were also included to examine the same hypothesis in additionally conditions of increased and decreased myocardial contractility in each animal. Paired comparisons were made for different load states using the Wilcoxon’s Signed Rank test. Results The inferior vena cava balloon occlusion (IVCBO load change compared for first to last beat resulted in LV twist increase (11.67° ±2.65° vs. 16.17° ±3.56° respectively, p  Conclusions Peak systolic LV twist and peak early diastolic untwisting rate are load dependent. Differences in LV load should be included in the interpretation when serial measures of twist are compared.

  20. Pathophysiology of acute heart failure: a world to know.

    Science.gov (United States)

    Sánchez-Marteles, M; Rubio Gracia, J; Giménez López, I

    2016-01-01

    Our understanding of the pathophysiological mechanisms of heart failure (HF) has changed considerably in recent years, progressing from a merely haemodynamic viewpoint to a concept of systemic and multifactorial involvement in which numerous mechanisms interact and concatenate. The effects of these mechanisms go beyond the heart itself, to other organs of vital importance such as the kidneys, liver and lungs. Despite this, the pathophysiology of acute HF still has aspects that elude our deeper understanding. Haemodynamic overload, venous congestion, neurohormonal systems, natriuretic peptides, inflammation, oxidative stress and its repercussion on cardiac and vascular remodelling are currently considered the main players in acute HF. Starting with the concept of acute HF, this review provides updates on the various mechanisms involved in this disease. Copyright © 2015 Elsevier España, S.L.U. y Sociedad Española de Medicina Interna (SEMI). All rights reserved.