Myocardial perfusion imaging by digital subtraction angiography

International Nuclear Information System (INIS)

Kadowaki, Hiroyuki; Ishikawa, Kinji; Ogai, Toshihiro; Katori, Ryo

1986-01-01

Several methods of digital subtraction angiography (DSA) were compared to determine which could better visualize regional myocardial perfusion using coronary angiography in seven patients with myocardial infarction, two with angina pectoris and five with normal coronary arteries. Satisfactory DSA was judged to be achieved if the shape of the heart on the mask film was identical to that on the live film and if both films were exactly superimposed. To obtain an identical mask film in the shape of each live film, both films were selected from the following three phases of the cardiac cycle; 1) at the R wave of the electrocardiogram, 2) 100 msec before the R wave, and 3) 200 msec before the R wave. The last two were superior for obtaining mask and live films which were similar in shape, because the cardiac motion in these phases was relatively small. Using these mask and live films, DSA was performed either with the continuous image mode (CI mode) or the time interval difference mode (TID mode). The overall perfusion of contrast medium through the artery to the vein was adequately visualized using the CI mode. Passage of contrast medium through the artery, capillary and vein was visualized at each phase using TID mode. Subtracted images were displayed and photographed, and the density of the contrast medium was adequate to display contour lines as in a relief map. Using this DSA, it was found that regional perfusion of the contrast medium was not always uniform in normal subjects, depending on the typography of the coronary artery. In all patients with anterior myocardial infarction, low perfusion was observed at the infarcted portion compared to the non-infarcted myocardium. In patients with inferior myocardial infarction, this low perfusion area was not observed because right coronary angiography was not subjected to DSA in this study. (J.P.N.)

Diagnosis of coronary stenosis using thallium-201 myocardial emission computed tomography

International Nuclear Information System (INIS)

Ito, Tsunaaki; Takeda, Hiroshi; Maeda, Hisato; Nakagawa, Tsuyoshi; Yamaguchi, Nobuo; Makino, Katsutoshi; Futagami, Yasuo; Konishi, Tokuji

1985-01-01

Thallium-201 myocardial emission computed tomography (ECT) was described with respect to methods of correcting ECT data and reconstructing the images, qualitative and quantitative diagnosis in the detection of coronary stenosis. Although 201 Tl myocardial ECT (using circumferential profile method combined with washout method) has relatively high diagnostic sensitivity, the correction of absorption is not satisfactory yet. Inside absorption coefficient is considered uniform by regarding the human body as oval shape. However, the chest, including the heart, lungs, vertebrae and thoracic wall, has four different absorption coefficients. If absorption can be corrected accurately, it will be possible to completely assess the myocardial blood flow by measuring the regional myocardial uptake of thallium-201. (Namekawa, K.)

Follow-up of regional myocardial T2 relaxation times in patients with myocardial infarction evaluated with magnetic resonance imaging

International Nuclear Information System (INIS)

Krauss, X.H.; Wall, E. van der; Laarse, A. van der; Dijkman, P.R.M. van; Bruschke, A.V.G.; Doornbos, J.; Roos, A. de; Voorthuisen, A.E. van

1990-01-01

Multi-echo spin-echo cardiac magnetic resonance imaging studies (echo times 30, 60, 90 and 120 ms) were performed in 19 patients with a 7-14-day (mean 10) old myocardial infarction and were repeated in 13 patients 4-7 months (mean 6) later. Also, 10 normal subjects were studied with magnetic resonance imaging. T2 relaxation times of certain left ventricular segments were calculated from the signal intensities at echo times of 30 and 90 ms. Compared to normal individuals, the mean T2 values on the early magnetic resonance images of the patients with inferior infarction showed significantly prolonged T2 times in the inferiorly localized segments, while on the follow-up magnetic resonance images the T2 times had almost returned to the normal range. Also the patients with anterior infarction showed significantly prolonged T2 times in the anteriorly localized segments on the early nuclear magnetic resonance images, but the T2 times remained prolonged at the follow-up magnetic resonance images. For every patient a myocardial damage score was determined, which was defined as the sum of the segmental T2 values in the patients minus the upper limit of normal T2 values obtained from the normal volunteers (= mean normal+2SD). The damage score on both the early and late magnetic resonance imaging study correlated well with the infarction size determined by myocardial enzyme release. Only the patients with an inferior infarction showed a significant decrease in damage score at follow-up magnetic resonance imaging. It is concluded that the regional T2 relaxation times are increased in infarcted myocardial regions and may remain prolonged for at least up to 7 months after the acute event, particularly in patients with an anterior infarction. These findings demonstrate the clinical potential of T2-weighted magnetic resonance imaging studies for detecting myocardial infarction, and estimating infarct size for an extended period after acute myocardial infarction. (author). 29 refs

Regional sympathetic denervation after myocardial infarction in humans detected noninvasively using I-123-metaiodobenzylguanidine

Energy Technology Data Exchange (ETDEWEB)

Stanton, M.S.; Tuli, M.M.; Radtke, N.L.; Heger, J.J.; Miles, W.M.; Mock, B.H.; Burt, R.W.; Wellman, H.N.; Zipes, D.P. (Indiana Univ. School of Medicine, IN (USA))

1989-11-15

Transmural myocardial infarction in dogs produces denervation of sympathetic nerves in viable myocardium apical to the infarct that may be arrhythmogenic. It is unknown whether sympathetic denervation occurs in humans. The purpose of this study was to use iodine-123-metaiodobenzylguanidine (MIBG), a radiolabeled guanethidine analog that is actively taken up by sympathetic nerve terminals, to image noninvasively the cardiac sympathetic nerves in patients with and without ventricular arrhythmias after myocardial infarction. Results showed that 10 of 12 patients with spontaneous ventricular tachyarrhythmias after myocardial infarction exhibited regions of thallium-201 uptake indicating viable perfused myocardium, with no MIBG uptake. Such a finding is consistent with sympathetic denervation. One patient had frequent episodes of nonsustained ventricular tachycardia induced at exercise testing that was eliminated by beta-adrenoceptor blockade. Eleven of the 12 patients had ventricular tachycardia induced at electrophysiologic study and metoprolol never prevented induction. Sympathetic denervation was also detected in two of seven postinfarction patients without ventricular arrhythmias. Normal control subjects had no regions lacking MIBG uptake. This study provides evidence that regional sympathetic denervation occurs in humans after myocardial infarction and can be detected noninvasively by comparing MIBG and thallium-201 images. Although the presence of sympathetic denervation may be related to the onset of spontaneous ventricular tachyarrhythmias in some patients, it does not appear to be related to sustained ventricular tachycardia induced at electrophysiologic study.

Regional Myocardial Blood Volume and Flow: First-Pass MR Imaging with Polylysine-Gd-DTPA

Science.gov (United States)

Wilke, Norbert; Kroll, Keith; Merkle, Hellmut; Wang, Ying; Ishibashi, Yukata; Xu, Ya; Zhang, Jiani; Jerosch-Herold, Michael; Mühler, Andreas; Stillman, Arthur E.; Bassingthwaighte, James B.; Bache, Robert; Ugurbil, Kamil

2010-01-01

The authors investigated the utility of an intravascular magnetic resonance (MR) contrast agent, poly-L-lysine-gadolinium diethylenetriaminepentaacetic acid (DTPA), for differentiating acutely ischemic from normally perfused myocardium with first-pass MR imaging. Hypoperfused regions, identified with microspheres, on the first-pass images displayed significantly decreased signal intensities compared with normally perfused myocardium (P < .0007). Estimates of regional myocardial blood content, obtained by measuring the ratio of areas under the signal intensity-versus-time curves in tissue regions and the left ventricular chamber, averaged 0.12 mL/g ± 0.04 (n = 35), compared with a value of 0.11 mL/g ± 0.05 measured with radiolabeled albumin in the same tissue regions. To obtain MR estimates of regional myocardial blood flow, in situ calibration curves were used to transform first-pass intensity-time curves into content-time curves for analysis with a multiple-pathway, axially distributed model. Flow estimates, obtained by automated parameter optimization, averaged 1.2 mL/min/g ± 0.5 [n = 29), compared with 1.3 mL/min/g ± 0.3 obtained with tracer microspheres in the same tissue specimens at the same time. The results represent a combination of T1-weighted first-pass imaging, intravascular relaxation agents, and a spatially distributed perfusion model to obtain absolute regional myocardial blood flow and volume. PMID:7766986

Noninvasive evaluation of regional myocardial perfusion in 112 patients using a mobile scintillation camera and intravenous nitrogen-13 labeled ammonia

International Nuclear Information System (INIS)

Walsh, W.F.; Harper, P.V.; Resnekov, L.; Fill, H.

1976-01-01

The short half-life positron emitter 13 N, as labeled ammonia ( 13 NH 4 + ), was evaluated as a myocardial imaging agent. Regional myocardial uptake of 13 NH 4 correlated with the distribution of labeled microspheres in experimental myocardial infarction. Using intravenous 13 NH 4 + , myocardial scintigraphy was performed in 85 cardiac patients and 27 normal subjects. Ninety-five scintigrams were suitable for analysis. Eighteen of 24 normal subjects had homogeneous myocardial images; six had inhomogeneous images attributable to early technical problems. Perfusion defects were observed in the scintigrams of 82% (57/65) of patients with coronary artery disease, being most common in patients with myocardial infarction (27/28). Six sequential studies showed changes in perfusion consistent with the clinical course of each patient. Scintigraphic abnormalities were also observed in 4/6 patients with valvular heart disease. 13 NH 4 + myocardial scintigraphy is a valid and sensitive method of assessing regional myocardial perfusion and is especially useful for sequential imaging at short intervals

Myocardial infarction

International Nuclear Information System (INIS)

Ando, Jyoji; Yasuda, Hisakazu; Miyamoto, Atsushi; Kobayashi, Tsuyoshi

1980-01-01

sup(99m)Tc-pyrophosphate (PYP) scintigraphy and 201 Tl myocardial scintigraphy were utilized for the diagnoses of the presence, the region, and the extent of myocardial infarction. Exercise 201 Tl myocardial scintigrams and exercise radionuclide ventriculography were utilized for diagnosis of coronary artery lesions in angina pectoris. Radionuclide ventriculography was used to investigate effects of coronary artery lesions on cardiac function and hemodynamics. In order to select adequate treatments for myocardial infarction and estimate the prognosis, it was necessary to detect the presence, the region, and the extent of acute myocardial infarction and to investigate effects of partial infarction on hemodynamics by using radionuclide imaging. Exercise myocardial scintigraphy could be carried out noninvasively and repeatedly for diagnosis of coronal artery disease. Therefore, this method could be applied widely. It was possible to use this method as a screening test of coronary artery diseases for the diagnoses of asymptomatic patients who showed ST changes in ECG, the patients with cardiac neurosis and the patency after a reconstructive surgery of coronary artery. (Tsunoda, M.)

The relationship between myocardial blood flow and myocardial viability after reperfusion. Myocardial viability assessed by 15O-water-PET

International Nuclear Information System (INIS)

Tsukagoshi, Joichi

1994-01-01

The purpose of this study was to examine the relationship between myocardial blood flow and myocardial viability in the ischemic canine myocardium after reperfusion. Transient ischemia was induced by 60-, 90-, and 180-minute occlusion of the left anterior descending coronary artery. Myocardial blood flow (MBF) was measured in the areas in which regional contractility was severely impaired (ehocardiographically akinetic or dyskinetic) in the early reperfusion period by 15 O-water positron emission tomography (PET) 12 hours and 4 weeks after reperfusion. An MBF ratio of ischemic to nonischemic regions 12 hours after reperfusion was inversely correlated with the amount of histologically determined tissue necrosis (r=-0.74). The regional contractility recovered 4 weeks later in the areas where an MBF ratio was 0.48 or greater, but did not recover in the areas with a lower MBF ratio. Thus, myocardial viability can be appropriately predicted in the early phase of myocardial perfusion by PET with 15 O-water even in the absence of metabolic imaging. (author)

Noninvasive evaluation of regional myocardial perfusion in 112 patients using a mobile scintillation camera and intravenous nitrogen-13 labeled ammonia

Energy Technology Data Exchange (ETDEWEB)

Walsh, W.F.; Harper, P.V.; Resnekov, L.; Fill, H.

1976-08-01

The short half-life positron emitter /sup 13/N, as labeled ammonia (/sup 13/NH/sub 4//sup +/), was evaluated as a myocardial imaging agent. Regional myocardial uptake of /sup 13/NH/sub 4/ correlated with the distribution of labeled microspheres in experimental myocardial infarction. Using intravenous /sup 13/NH/sub 4//sup +/, myocardial scintigraphy was performed in 85 cardiac patients and 27 normal subjects. Ninety-five scintigrams were suitable for analysis. Eighteen of 24 normal subjects had homogeneous myocardial images; six had inhomogeneous images attributable to early technical problems. Perfusion defects were observed in the scintigrams of 82% (57/65) of patients with coronary artery disease, being most common in patients with myocardial infarction (27/28). Six sequential studies showed changes in perfusion consistent with the clinical course of each patient. Scintigraphic abnormalities were also observed in 4/6 patients with valvular heart disease. /sup 13/NH/sub 4//sup +/ myocardial scintigraphy is a valid and sensitive method of assessing regional myocardial perfusion and is especially useful for sequential imaging at short intervals.

Shape Analysis of HII Regions - I. Statistical Clustering

Science.gov (United States)

Campbell-White, Justyn; Froebrich, Dirk; Kume, Alfred

2018-04-01

We present here our shape analysis method for a sample of 76 Galactic HII regions from MAGPIS 1.4 GHz data. The main goal is to determine whether physical properties and initial conditions of massive star cluster formation is linked to the shape of the regions. We outline a systematic procedure for extracting region shapes and perform hierarchical clustering on the shape data. We identified six groups that categorise HII regions by common morphologies. We confirmed the validity of these groupings by bootstrap re-sampling and the ordinance technique multidimensional scaling. We then investigated associations between physical parameters and the assigned groups. Location is mostly independent of group, with a small preference for regions of similar longitudes to share common morphologies. The shapes are homogeneously distributed across Galactocentric distance and latitude. One group contains regions that are all younger than 0.5 Myr and ionised by low- to intermediate-mass sources. Those in another group are all driven by intermediate- to high-mass sources. One group was distinctly separated from the other five and contained regions at the surface brightness detection limit for the survey. We find that our hierarchical procedure is most sensitive to the spatial sampling resolution used, which is determined for each region from its distance. We discuss how these errors can be further quantified and reduced in future work by utilising synthetic observations from numerical simulations of HII regions. We also outline how this shape analysis has further applications to other diffuse astronomical objects.

Myocardial temperature variation: effect on regional function and coronary flow in dogs

International Nuclear Information System (INIS)

D'Ambra, M.N.; Magrassi, P.; Lowenstein, E.; Kyo, S.; Austen, W.G.; Buckley, M.J.; LaRaia, P.J.

1987-01-01

Incremental changes in the temperature (28-42.5 0 C) of the anterior left ventricular wall in a canine, working, beating right heart bypass preparation (constant preload, afterload, and heart rate) were produced to measure the effect of regional temperature on myocardial function and blood flow. Circumferential-axis segment lengths were measured with sonomicrometry in both the temperature-varied, left-anterior descending coronary artery (LAD)-supplied myocardium and the normothermic (38 0 C) circumflex-supplied myocardium. Fast thermistors (time constant 0 C), regional systolic shortening decreased 42.2 +/- 10% at 41 0 C and increased 23.3 +/- 6% at 31 0 C. There was no significant change in coronary blood flow or distribution at the three temperatures. Pressure-length areas varied inversely with myocardial temperature. These data demonstrate that there is a reversible inverse relationship between midwall T and ventricular function when heart rate, preload, and afterload are controlled

[Myocardial perfusion imaging by digital subtraction angiography].

Science.gov (United States)

Kadowaki, H; Ishikawa, K; Ogai, T; Katori, R

1986-03-01

Several methods of digital subtraction angiography (DSA) were compared to determine which could better visualize regional myocardial perfusion using coronary angiography in seven patients with myocardial infarction, two with angina pectoris and five with normal coronary arteries. Satisfactory DSA was judged to be achieved if the shape of the heart on the mask film was identical to that on the live film and if both films were exactly superimposed. To obtain an identical mask film in the shape of each live film, both films were selected from the following three phases of the cardiac cycle; at the R wave of the electrocardiogram, 100 msec before the R wave, and 200 msec before the R wave. The last two were superior for obtaining mask and live films which were similar in shape, because the cardiac motion in these phases was relatively small. Using these mask and live films, DSA was performed either with the continuous image mode (CI mode) or the time interval difference mode (TID mode). The overall perfusion of contrast medium through the artery to the vein was adequately visualized using the CI mode. Passage of contrast medium through the artery, capillary and vein was visualized at each phase using TID mode. Subtracted images were displayed and photographed, and the density of the contrast medium was adequate to display contour lines as in a relief map. Using this DSA, it was found that regional perfusion of the contrast medium was not always uniform in normal subjects, depending on the typography of the coronary artery.(ABSTRACT TRUNCATED AT 250 WORDS)

Three-dimensional regional strain analysis in porcine myocardial infarction: a 3T magnetic resonance tagging study

Directory of Open Access Journals (Sweden)

Soleimanifard Sahar

2012-12-01

Full Text Available Abstract Background Previous studies of mechanical strain anomalies in myocardial infarction (MI have been largely limited to analysis of one-dimensional (1D and two-dimensional (2D strain parameters. Advances in cardiovascular magnetic resonance (CMR methods now permit a complete three-dimensional (3D interrogation of myocardial regional strain. The aim of this study was to investigate the incremental value of CMR-based 3D strain and to test the hypothesis that 3D strain is superior to 1D or 2D strain analysis in the assessment of viability using a porcine model of infarction. Methods Infarction was induced surgically in 20 farm pigs. Cine, late gadolinium enhancement, and CMR tagging images were acquired at 11 days before (baseline, and 11 days (early and 1 month (late after induction of infarct. Harmonic phase analysis was performed to measure circumferential, longitudinal, and radial strains in myocardial segments, which were defined based on the transmurality of delayed enhancement. Univariate, bivariate, and multivariate logistic regression models of strain parameters were created and analyzed to compare the overall diagnostic accuracy of 3D strain analysis with 1D and 2D analyses in identifying the infarct and its adjacent regions from healthy myocardium. Results 3D strain differed significantly in infarct, adjacent, and remote segments (p  Conclusions Cumulative 3D strain information accurately identifies infarcts and their neighboring regions from healthy myocardium. The 3D interrogation of myocardial contractility provides incremental diagnostic accuracy in delineating the dysfunctional and nonviable myocardium in comparison with 1D or 2D quantification of strain. The infarct neighboring regions are the major beneficiaries of the 3D assessment of regional strain.

Regional myocardial oxygen consumption estimated by carbon-11 acetate and positron emission tomography before and after repetitive ischemia

DEFF Research Database (Denmark)

Kofoed, K F; Hansen, P R; Holm, S

2011-01-01

Preserved myocardial oxygen consumption estimated by carbon 11-acetate and positron emission tomography (PET) in myocardial regions with chronic but reversibly depressed contractile function in patients with ischemic heart disease have been suggested to be caused by repeated short episodes of acu...

The relationship between myocardial blood flow and myocardial viability after reperfusion. Myocardial viability assessed by [sup 15]O-water-PET

Energy Technology Data Exchange (ETDEWEB)

Tsukagoshi, Joichi (Gunma Univ., Maebashi (Japan). School of Medicine)

1994-09-01

The purpose of this study was to examine the relationship between myocardial blood flow and myocardial viability in the ischemic canine myocardium after reperfusion. Transient ischemia was induced by 60-, 90-, and 180-minute occlusion of the left anterior descending coronary artery. Myocardial blood flow (MBF) was measured in the areas in which regional contractility was severely impaired (ehocardiographically akinetic or dyskinetic) in the early reperfusion period by [sup 15]O-water positron emission tomography (PET) 12 hours and 4 weeks after reperfusion. An MBF ratio of ischemic to nonischemic regions 12 hours after reperfusion was inversely correlated with the amount of histologically determined tissue necrosis (r=-0.74). The regional contractility recovered 4 weeks later in the areas where an MBF ratio was 0.48 or greater, but did not recover in the areas with a lower MBF ratio. Thus, myocardial viability can be appropriately predicted in the early phase of myocardial perfusion by PET with [sup 15]O-water even in the absence of metabolic imaging. (author).

Detection of regional derangements in myocardial metabolism by positron computed tomography in Duchenne's muscular dystrophy

International Nuclear Information System (INIS)

Henze, E.; Schelbert, H.R.; Perloff, J.K.; Schwaiger, M.; Phelps, M.E.

1982-01-01

Duchenne's Muscular Dystrophy is unique in genetically targeting for disease a specific region of myocardium: the postero-basal left ventricular wall. Postmortem examinations revealed focal fibrous degenerations in the postero-basal segment, while the coronary arteries were usually not affected. A predystrophic metabolic fault has been postulated for this region. This hypothesis was tested with positron computed tomography as a new means for the noninvasive study of regional myocadial perfusion and metabolism and to determine the incidence of regional and global left ventricular dysfunction and perfusion abnormalities using Thallium-201 and gated blood pool imaging. Myocardial perfusion was evaluated with N-13 ammonia while regional myocardial glucose uptake was studied with the glucose analog F-18 DG. The sensitivity of each diagnostic test for detecting cardiac involvement in Duchenne's Muscular Dystrophy was evaluated. It was highest for ammonia and glucose imaging and it was low for Thallium and radionuclide blood pool imaging

Regional myocardial metabolism in patients with acute myocardial infarction assessed by positron emission tomography

International Nuclear Information System (INIS)

Schwaiger, M.; Brunken, R.; Grover-McKay, M.; Krivokapich, J.; Child, J.; Tillisch, J.H.; Phelps, M.E.; Schelbert, H.R.

1986-01-01

Positron emission tomography has been shown to distinguish between reversible and irreversible ischemic tissue injury. Using this technique, 13 patients with acute myocardial infarction were studied within 72 hours of onset of symptoms to evaluate regional blood flow and glucose metabolism with nitrogen (N)-13 ammonia and fluorine (F)-18 deoxyglucose, respectively. Serial noninvasive assessment of wall motion was performed to determine the prognostic value of metabolic indexes for functional tissue recovery. Segmental blood flow and glucose utilization were evaluated using a circumferential profile technique and compared with previously established semiquantitative criteria. Relative N-13 ammonia uptake was depressed in 32 left ventricular segments. Sixteen segments demonstrated a concordant decrease in flow and glucose metabolism. Regional function did not change over time in these segments. In contrast, 16 other segments with reduced blood flow revealed maintained F-18 deoxyglucose uptake consistent with remaining viable tissue. The average wall motion score improved significantly in these segments (p less than 0.01), yet the degree of recovery varied considerably among patients. Coronary anatomy was defined in 9 of 13 patients: patent infarct vessels supplied 8 of 10 segments with F-18 deoxyglucose uptake, while 10 of 13 segments in the territory of an occluded vessel showed concordant decreases in flow and metabolism (p less than 0.01). Thus, positron emission tomography reveals a high incidence of residual tissue viability in ventricular segments with reduced flow and impaired function during the subacute phase of myocardial infarction. Absence of residual tissue metabolism is associated with irreversible injury, while preservation of metabolic activity identifies segments with a variable outcome.(ABSTRACT TRUNCATED AT 250 WORDS)

Regional myocardial oxygen consumption estimated by carbon-11 acetate and positron emission tomography before and after repetitive ischemia

DEFF Research Database (Denmark)

Kofoed, K F; Hansen, P R; Holm, S

2000-01-01

alternating with 5 minutes of reperfusion. Before and after repetitive coronary occlusions, oxygen 15 water/oxygen 15 carbon monoxide (blood flow), and 11C-acetate (oxygen consumption) PET imaging were performed. Left ventricular regional systolic wall thickening was measured with sonomicrometry. Forty......BACKGROUND: Preserved myocardial oxygen consumption estimated by carbon 11-acetate and positron emission tomography (PET) in myocardial regions with chronic but reversibly depressed contractile function in patients with ischemic heart disease have been suggested to be caused by repeated short......-five minutes after the ischemic episodes, systolic ventricular wall thickening was decreased by 90%, whereas myocardial blood flow was reduced by 21% compared with baseline values (P consumption was unaltered compared with the baseline level...

Evaluation of right ventricular regional wall motion in inferior myocardial infarction by cine MRI

International Nuclear Information System (INIS)

Nishino, Masami; Ohnishi, Shusaku; Hasegawa, Shinji

1991-01-01

The purpose of this study is to evaluate right ventricular regional wall motion in inferior myocardial infarction by cine MRI. Thirteen patients with inferior myocardial infarction were investigated by cine MRI and were divided into proximal group which consisted of seven patients: >90% stenosis in segment 1 or 2 of right coronary artery and distal group which consisted of six patients: >90% stenosis in segment 3 or 4 of right coronary artery. Cine MRI was performed by 1.5 tesla magnet system (Signa, GE). To depict the regional asynergy, right ventricular wall was divided into 6 segments as follows: Segments 1 and 2 were upper and lower segments in transverse planes, respectively. Segments 3 and 4 were free wall and diaphragmatic segments of outflow tract, and segments 5 and 6 were of inflow tract in sagittal planes. Our results were as follows: (1) In proximal group, right ventricular asynergy was detected in six patients but in distal group it was detected in only one patient; (2) Right ventricular asynergy was detected most frequently at diaphragmatic segments in sagittal planes; (3) All the patients who had shown the hemodynamic deterioration of right ventricle on acute phase of inferior myocardial infarction presented the broad asynergy in right ventricle; (4) Cine MRI is clinically useful in evaluating right ventricular regional wall movement and diagnosing right ventricular infarction. (author)

Clinical use of 201Tl myocardial scintigraphy

International Nuclear Information System (INIS)

Senda, Kohei; Imaeda, Takeyoshi; Kato, Toshimitsu; Asada, Shuichi; Doi, Hidetaka

1977-01-01

Myocardial imaging with 201 Tl and scinticamera was studied experimentally using specially designed phantoms and clinically in 23 patients with myocardial infarction or other heart disease. In the phantom experiment, quality of image, accumulative count rate, and detectability of the defect were compared to obtain the best technique for their detection, using four different collimators, i.e., converging, pin-hole, 4000-hole, and 140 keV high-resolution, at two photopeak levels of 201 Tl of 75 and 167 keV, and combining a radiation absorber. In patient examination, myocardial images taken at different periods after injection, different detecting conditions of the scinticamera, and various detecting projections were compared. Images of the converging collimator at the 75 keV photopeak revealed considerably higher accumulative counts and relatively higher quality than those of other detecting conditions. It was necessary to take as many images as possible in various projections, in order to detect the location and size of the myocardial ischemic lesion because the lesion was demonstrated as a clear defect only in profile. It became evident that images taken between about 25 and 90 min delineated the myocardium more clearly than those taken in other periods. Normal images taken in 8 patients without ischemic heart disease appeared in the shape of a doughnut of horseshoe, demonstrating mainly the left venticular myocardium. The image was faint in the region of the aortic or mitral valve and thin in the region of the apical wall. A faint image of the right ventricular myocardium was sometimes seen. In 3 patients with valvular heart disease, findings suggested changes in the thickness of myocardium and the distribution of coronary blood flow. In 11 of 12 patients with old myocardial infarction, the location and size of the lesion was detected. (Evans, J.)

Relationship between regional myocardial blood flow and thallium-201 distribution in the presence of coronary artery stenosis and dipyridamole-induced vasodilation

International Nuclear Information System (INIS)

Mays, A.E. Jr.; Cobb, F.R.

1984-01-01

This study assesses the relationship between the distribution of thallium-201 and myocardial blood flow during coronary vasodilation induced by intravenous dipyridamole in canine models of partial and complete coronary artery stenosis. 10 dogs were chronically instrumented with catheters in the left atrium and aorta and with a balloon occluder and electromagnetic flow probe on the proximal left circumflex coronary artery. Regional myocardial blood flow was measured during control conditions with radioisotope-labeled microspheres, and the phasic reactive hyperemic response to a 20-s transient occlusion was then recorded. Dipyridamole was then infused intravenously until phasic coronary blood flow increased to match peak hyperemic values. The left circumflex coronary artery was either partially occluded to reduce phasic blood flow to control values (group 1) or it was completely occluded (group 2), and thallium-201 and a second microsphere label were injected. 5 min later, the animals were sacrificed, the left ventricle was sectioned into 1-2-g samples, and thallium-201 activity and regional myocardial blood flow were measured. Curvilinear regression analyses between thallium-201 localization and myocardial blood flow during dipyridamole infusion demonstrated a slightly better fit to a second- as compared with a first-order model, indicating a slight roll-off of thallium activity as myocardial blood flow increases. During the dipyridamole infusion, the increases in phasic blood flow, the distributions of regional myocardial blood flow, and the relationships between thallium-201 localization and regional blood flow were comparable to values previously observed in exercising dogs with similar occlusions. These data provide basic validation that supports the use of intravenous dipyridamole and thallium-201 as an alternative to exercise stress and thallium-201 for evaluating the effects of coronary occlusive lesions on the distribution of regional myocardial blood flow

Quantitative analysis of regional myocardial performance in coronary artery disease

Science.gov (United States)

Stewart, D. K.; Dodge, H. T.; Frimer, M.

1975-01-01

Findings from a group of subjects with significant coronary artery stenosis are given. A group of controls determined by use of a quantitative method for the study of regional myocardial performance based on the frame-by-frame analysis of biplane left ventricular angiograms are presented. Particular emphasis was placed upon the analysis of wall motion in terms of normalized segment dimensions, timing and velocity of contraction. The results were compared with the method of subjective assessment used clinically.

Identification of Y-shaped and O-shaped diffusion regions during magnetic reconnection in a laboratory plasma

International Nuclear Information System (INIS)

Yamada, Masaaki; Ji, H.; Hsu, S.; Carter, T.; Kulsrud, R.; Ono, Yasushi; Perkins, F.

1997-01-01

Two strikingly different shapes of diffusion regions are identified during magnetic reconnection in a magnetohydrodynamic laboratory plasma. The shapes depend on the third vector component of the reconnecting magnetic fields. Without the third component (anti-parallel or null-helicity reconnection), a thin double-Y shaped diffusion region is identified. In this case, the neutral sheet current profile is accurately measured to be as narrow as the order of the ion gyro-radius. In the presence of an appreciable third component (co-helicity reconnection), an O-shaped diffusion region appears and grows into a spheromak configuration

Regional wall thickening in gated myocardial perfusion SPECT in a Japanese population: effect of sex, radiotracer, rotation angles and frame rates

Energy Technology Data Exchange (ETDEWEB)

Akhter, Nasima; Nakajima, Kenichi; Okuda, Koichi; Matsuo, Shinro; Yoneyama, Tatsuya; Taki, Junichi; Kinuya, Seigo [Kanazawa University Hospital, Department of Nuclear Medicine, Kanazawa, Ishikawa (Japan)

2008-09-15

Gated single-photon emission computed tomography (SPECT) imaging of myocardium by {sup 99m}Tc and {sup 201}Tl is used extensively to measure quantitative cardiac functional parameters. However, factors affecting normal values for myocardial functional parameters and population-specific standards have not yet been established. The aim of the study was to determine the effect of sex, radiotracer, rotation angles and frame rates on resting myocardial wall thickening (WT) and to develop a Japanese standard of normal values for WT. Data from a total of 202 patients with low possibility of having cardiac problems were collected from nine hospitals throughout Japan. Patients were divided into five groups according to study protocol, and WT was evaluated according to the 17-segment and four-region (basal, mid and apical regions and the apex) polar map distribution. WT was generally higher in women than in men irrespective of the use of radiotracers, rotation angles or frame rates, and the difference was highly significant in the mid and apical regions. In any protocol used, resting myocardial thickening in the apex was higher than in the mid and apical regions, and thickening was lowest in the basal region, suggesting heterogeneous regional myocardial thickening (%) in normal subjects. Different rotation angles showed no significant change on WT, but different frame rates and tracers showed significant WT change in both sexes. Percent thickening of the myocardium was significantly higher in imaging by {sup 99m}Tc-labelled tracers than in {sup 201}Tl. Sex, radiotracers and frame rates had a significant effect on myocardial thickening, and the importance of population-specific standards should be emphasized. A normal database can serve as a standard for gated SPECT evaluation of myocardial thickening in a Japanese population and might be applicable to Asian populations having a similar physique. (orig.)

Quantitative assessment of regional myocardial flow reserve using Tc-99m-sestamibi imaging. Comparison with results of O-15 water PET

International Nuclear Information System (INIS)

Tsukamoto, Takahiro; Ito, Yoshinori; Noriyasu, Kazuyuki; Morita, Koichi; Katoh, Chietsugu; Okamoto, Hiroshi; Tamaki, Nagara

2005-01-01

The aims of this study were to develop a method for quantitative estimation of the myocardial blood flow index (MBFI) and myocardial flow reserve (MFR) of the whole left ventricle using 99m technetium (Tc-99m)-sestamibi imaging. Twenty-two patients with suspected coronary artery disease and 7 controls underwent both Tc-99m-sestamibi imaging and O-15 water positron emission tomography (PET). The global MBFI was calculated on the basis of the microsphere model from the ratio of the myocardial count to the area under the time-activity curve on the aortic arch. The regional MBFI was calculated from the relative distributions of Tc-99m-sestamibi uptake values. The regional MBFI and MFR (Tc-MFR) obtained using single-photon emission computed tomography were compared with the myocardial blood flow (MBF) and MFR (PET-MFR) obtained using PET as the gold standard. Regional MBFI significantly correlated with the MBF obtained using PET. Regional Tc-MFR also correlated with the regional PET-MER, with some underestimation. These results indicate that regional MBF and MFR may be estimated by dynamic Tc-99m-sestamibi imaging and can be used for the early detection and estimation of the functional severity of coronary lesions without the need for a PET camera. (author)

In vivo assessment of regional mechanics post-myocardial infarction: A focus on the road ahead.

Science.gov (United States)

Romito, Eva; Shazly, Tarek; Spinale, Francis G

2017-10-01

Cardiovascular disease, particularly the occurrence of myocardial infarction (MI), remains a leading cause of morbidity and mortality (Go et al., Circulation 127: e6-e245, 2013; Go et al. Circulation 129: e28-e292, 2014). There is growing recognition that a key factor for post-MI outcomes is adverse remodeling and changes in the regional structure, composition, and mechanical properties of the MI region itself. However, in vivo assessment of regional mechanics post-MI can be confounded by the species, temporal aspects of MI healing, as well as size, location, and extent of infarction across myocardial wall. Moreover, MI regional mechanics have been assessed over varying phases of the cardiac cycle, and thus, uniform conclusions regarding the material properties of the MI region can be difficult. This review assesses past studies that have performed in vivo measures of MI mechanics and attempts to provide coalescence on key points from these studies, as well as offer potential recommendations for unifying approaches in terms of regional post-MI mechanics. A uniform approach to biophysical measures of import will allow comparisons across studies, as well as provide a basis for potential therapeutic markers.

Quantification of Regional Myocardial Oxygenation by Magnetic Resonance Imaging: Validation with Positron Emission Tomography

Science.gov (United States)

McCommis, Kyle S.; Goldstein, Thomas A.; Abendschein, Dana R.; Herrero, Pilar; Misselwitz, Bernd; Gropler, Robert J.; Zheng, Jie

2011-01-01

Background A comprehensive evaluation of myocardial ischemia requires measures of both oxygen supply and demand. Positron emission tomography (PET) is currently the gold standard for such evaluations, but its use is limited due to its ionizing radiation, limited availability, and high cost. A cardiac magnetic resonance imaging (MRI) method was developed for assessing myocardial oxygenation. The purpose of this study was to evaluate and validate this technique compared to PET during pharmacologic stress in a canine model of coronary artery stenosis. Methods and Results Twenty-one beagles and small mongrel dogs without coronary artery stenosis (controls), or with moderate to severe acute coronary artery stenosis underwent MRI and PET imaging at rest and during dipyridamole vasodilation or dobutamine stress to induce a wide range of changes in cardiac perfusion and oxygenation. MRI first-pass perfusion imaging was performed to quantify myocardial blood flow (MBF) and volume (MBV). The MRI blood-oxygen-level-dependent (BOLD) technique was used to determine the myocardial oxygen extraction fraction (OEF) during pharmacologic hyperemia. Myocardial oxygen consumption (MVO2) was determined by Fick’s law. In the same dogs, 15O-water and 11C-acetate were used to measure MBF and MVO2, respectively, by PET. Regional assessments were performed for both MR and PET. MRI data correlated nicely with PET values for MBF (R2 = 0.79, P < 0.001), MVO2 (R2 = 0.74, P < 0.001), and OEF (R2 = 0.66, P < 0.01). Conclusions Cardiac MRI methods may provide an alternative to radionuclide imaging in settings of myocardial ischemia. Our newly developed quantitative MRI oxygenation imaging technique may be a valuable non-invasive tool to directly evaluate myocardial energetics and efficiency. PMID:19933371

Clinical use of /sup 201/Tl myocardial scintigraphy

Energy Technology Data Exchange (ETDEWEB)

Senda, K; Imaeda, T; Kato, T; Asada, S; Doi, H

1977-04-01

Myocardial imaging with /sup 201/Tl and scinticamera was studied experimentally using specially designed phantoms and clinically in 23 patients with myocardial infarction or other heart disease. In the phantom experiment, quality of image, accumulative count rate, and detectability of the defect were compared to obtain the best technique for their detection, using four different collimators, i.e., converging, pin-hole, 4000-hole, and 140 keV high-resolution, at two photopeak levels of /sup 201/Tl of 75 and 167 keV, and combining a radiation absorber. In patient examination, myocardial images taken at different periods after injection, different detecting conditions of the scinticamera, and various detecting projections were compared. Images of the converging collimator at the 75 keV photopeak revealed considerably higher accumulative counts and relatively higher quality than those of other detecting conditions. It was necessary to take as many images as possible in various projections, in order to detect the location and size of the myocardial ischemic lesion because the lesion was demonstrated as a clear defect only in profile. It became evident that images taken between about 25 and 90 min delineated the myocardium more clearly than those taken in other periods. Normal images taken in 8 patients without ischemic heart disease appeared in the shape of a doughnut of horseshoe, demonstrating mainly the left venticular myocardium. The image was faint in the region of the aortic or mitral valve and thin in the region of the apical wall. A faint image of the right ventricular myocardium was sometimes seen. In 3 patients with valvular heart disease, findings suggested changes in the thickness of myocardium and the distribution of coronary blood flow. In 11 of 12 patients with old myocardial infarction, the location and size of the lesion was detected.

Increased Regional Epicardial Fat Volume Associated with Reversible Myocardial Ischemia in Patients with Suspected Coronary Artery Disease

Science.gov (United States)

Khawaja, Tuba; Greer, Christine; Thadani, Samir R.; Kato, Tomoko S.; Bhatia, Ketan; Shimbo, Daichi; Konkak, Andrew; Bokhari, Sabahat; Einstein, Andrew J.; Schulze, P. Christian

2015-01-01

Epicardial adipose tissue is a source of pro-inflammatory cytokines and has been linked to the development of coronary artery disease. No study has systematically assessed the relationship between local epicardial fat volume (EFV) and myocardial perfusion defects. We analyzed EFV in patients undergoing SPECT myocardial perfusion imaging combined with computed tomography (CT) for attenuation correction. Low-dose CT without contrast was performed in 396 consecutive patients undergoing SPECT imaging for evaluation of coronary artery disease. Regional thickness, cross-sectional areas, and total EFV were assessed. 295 patients had normal myocardial perfusion scans and 101 had abnormal perfusion scans. Mean EFVs in normal, ischemic, and infarcted hearts were 99.8 ± 82.3 cm3, 156.4 ± 121.9 cm3, and 96.3 ± 102.1 cm3, respectively (P < 0.001). Reversible perfusion defects were associated with increased local EFV compared to normal perfusion in the distribution of the right (69.2 ± 51.5 vs 46.6 ± 32.0 cm3; P = 0.03) and left anterior descending coronary artery (87.1 ± 76.4 vs 46.7 ± 40.6 cm3; P = 0.005). Our results demonstrate increased regional epicardial fat in patients with active myocardial ischemia compared to patients with myocardial scar or normal perfusion on nuclear perfusion scans. Our results suggest a potential role for cardiac CT to improve risk stratification in patients with suspected coronary artery disease. PMID:25339129

Clinical Significance of Reverse Redistribution Phenomenon on Delayed Tc-99m Tetrofosmin Myocardial Perfusion Imaging in Patients with Acute Myocardial Infarction

International Nuclear Information System (INIS)

Park, Soon Ah; Kim, Dae Weung; Kim, Chang Guhn; Jeong, Jin Won; Kim, Nam Ho; Yun, Kyeong Ho

2009-01-01

This study was performed to investigate the clinical significance of reverse redistribution (RR) phenomenon detected on delayed Tc-99m tetrofosmin myocardial single photon emission computed tomography (SPECT) in patients with acute myocardial infarction after revascularization. A Tc-99m tetrofrosmin myocardial SPECT was performed in 67 consecutive patients after revascularization for acute myocardial infarction. Myocardial SPECT imaging was performed for early imaging at 40 min and for delayed imaging at 180 min after reinjection at myocardial stress. Regional myocardial uptakes were scored by 4-point scoring in the left ventricular wall divided into 17 segments. Reverse redistribution was defined as an increase of more than 2 point in the activity score on the delayed image. Follow-up myocardial SPECT and coronary angiography (CAG) were performed 9 months later. On myocardial SPECT performed following revascularization, RR was observed in 100 of all 319 segments (31%) and in 43 patients (64%). The abnormalities of perfusion and regional wall motion were more severe in the patients with RR compared to those without RR (p<0.05). On follow-up myocardial SPECT, the myocardial perfusion, regional wall motion, and myocardial thickness were significantly improved in the patients with RR (p<0.05) however, these changes were not significant in those without RR. There was no significant difference between the patients with RR and those without RR in the occurrence of restenosis on CAG. In patients with acute myocardial infarction, the regions showing the RR phenomenon on delayed Tc-99m tetrofosmin SPECT may reflect viable myocardium and indicate recovery of salvaged myocardium

Ventricular and myocardial scintiscanning: Methodical fundamentals

International Nuclear Information System (INIS)

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

1984-01-01

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

Is the time between onset of pain and restoration of patency of infarct-related artery shortened in patients with myocardial infarction? The effects of the Kielce Region System for Optimal Management of Acute Myocardial Infarction

Directory of Open Access Journals (Sweden)

Marcin Sadowski

2014-09-01

Full Text Available Introduction : The importance of delay in the restoration of infarct-related artery patency in patients with myocardial infarction was discussed, and actions were undertaken in the Kielce Region aimed at shortening this time within the System for Optimal Management of Acute Myocardial Infarction. Aim of the research: To evaluate the effectiveness of shortening time delays during transport of patients and diagnostics of myocardial infarction in the Kielce Region. Material and methods: Time delays were analysed in 5,934 patients with ST-segment elevation myocardial infarction (STEMI, hospitalised in cardiology wards with interventional cardiology on 24-hour duty, during the period 2008–2012. Time delays were analysed between the onset of myocardial infarction pain and undertaking treatment – T1 and T2 time – within which a patient with myocardial infarction, after admission to hospital, has intervention performed on infarct-related coronary artery. Results : During the period 2008–2012, the median T1 time was successfully shortened from 355 to 203 min, and the T2 time from 101 to 48 min. Conclusions: The effectiveness of the system was confirmed, and the necessity for further improvement of the system indicated.

Validation of quantitation of regional myocardial blood flow in vivo with 11C-labeled human albumin microspheres and positron emission tomography

International Nuclear Information System (INIS)

Wilson, R.A.; Shea, M.J.; De Landsheere, C.M.; Turton, D.; Brady, F.; Deanfield, J.E.; Selwyn, A.P.

1984-01-01

Use of radiolabeled microspheres is a standard method to measure regional myocardial perfusion in animals. Human albumin microspheres have been given safely to patients, but positron-emitting 67 Ga-labeled human albumin microspheres are characterized by an unstable radiolabel. A new labeling procedure that covalently binds 11 C to human albumin microspheres via 11 CH 3 I was developed. Seven open-chest and two closed-chest dogs were studied. Reference and 11 C-labeled human albumin microspheres (2 to 25 mCi) were both injected into the left atrium. Positron tomographic images were obtained of the myocardial distribution of the 11 C-labeled microspheres. Timed arterial withdrawal was used for both reference gamma-labeled microspheres and 11 C-labeled human albumin microspheres. Regional myocardial perfusion calculated by this technique correlated well with values obtained with reference microspheres over a range of 0.2 to 3.5 ml/min/g. Thus, 11 C human albumin microspheres are stable radiochemically and can be used as a quantitative measure of regional myocardial perfusion

Effect of eating on thallium-201 myocardial redistribution after myocardial ischemia

International Nuclear Information System (INIS)

Angello, D.A.; Wilson, R.A.; Palac, R.T.

1987-01-01

To determine whether eating a high-carbohydrate meal between initial and delayed postexercise thallium-201 (Tl-201) imaging affects detection of Tl-201 redistribution during exercise stress testing, 16 patients with stable angina performed 2 Tl-201 treadmill exercise stress tests within a 14-day interval. Immediately after initial postexercise imaging, patients either drank a commercially available instant breakfast preparation for the intervention test or drank an equivalent volume of water for the control test. Comparable exercise workloads were achieved by exercising patients to the same heart rate for both tests. The order of the 2 (intervention and control) tests were randomized. All patients had at least 1 region of Tl-201 myocardial redistribution on either their eating or control test scans, although only 7 of the 16 had positive treadmill exercise test responses. Forty-six regions showing Tl-201 myocardial redistribution were identified in all 144 regions examined. Significantly more of these regions were identified on control test scans than on eating test scans: 11 of 46 on both test scans, 6 of 46 only on eating test scans and 29 of 46 only on control scans (p less than 0.001). Consistent with results of the quantitative regional analysis, the percentage of Tl-201 clearance over 4 hours in the 46 Tl-201 myocardial redistribution regions was 39 +/- 8% for the eating tests and 29 +/- 8% for control tests (mean +/- standard deviation, p less than 0.003). In 4 patients diagnosis of transient ischemia would have been missed because their 14 Tl-201 myocardial redistribution regions were detected only on the control test scans

Myocardial Blood Volume Is Associated with Myocardial Oxygen Consumption: An Experimental Study with CMR in a Canine Model

Science.gov (United States)

McCommis, Kyle S.; Zhang, Haosen; Goldstein, Thomas A.; Misselwitz, Bernd; Abendschein, Dana R.; Gropler, Robert J.; Zheng, Jie

2009-01-01

OBJECTIVES To evaluate the feasibility of cardiovascular MR (CMR) to determine regional myocardial perfusion and O2 metabolism, and assess the role of myocardial blood volume (MBV) on oxygen supply. BACKGROUND Coronary artery disease presents as an imbalance of myocardial oxygen supply and demand. We have developed relevant CMR methods to determine the relationship of myocardial blood flow (MBF) and MBV to oxygen consumption (MVO2) during pharmacologic hyperemia. METHODS Twenty-one mongrel dogs were studied with varying stenosis severities imposed on the proximal left anterior descending (LAD) coronary artery. MBF and MBV were determined by CMR first-pass perfusion, while the oxygen extraction fraction (OEF) and MVO2 were determined by the myocardial Blood-Oxygen-Level-Dependent (BOLD) effect and Fick’s law, respectively. MR imaging was performed at rest, and during either dipyridamole-induced vasodilation or dobutamine-induced hyperemia. Regional differences in myocardial perfusion and oxygenation were then evaluated. RESULTS Dipyridamole and dobutamine both led to 145–200% increases in MBF and 50–80% increases in MBV in normal perfused myocardium. As expected, MVO2 increased more significantly with dobutamine (~175%) than dipyridamole (~40%). Coronary stenosis resulted in an attenuation of MBF, MBV, and MVO2 in both the LAD-subtended stenosis region and the left circumflex subtended remote region. Liner regression analysis showed that MBV reserve appears to be more correlated with MVO2 reserve during dobutamine stress than MBF reserve, particularly in the stenotic regions. Conversely, MBF reserve appears to be more correlated with MVO2 reserve during dipyridamole, although neither of these differences was significant. CONCLUSIONS Noninvasive evaluation of both myocardial perfusion and oxygenation by CMR facilitates direct monitoring of regional myocardial ischemia and provides a valuable tool for better understanding microvascular pathophysiology. These

Three-dimension structure of ventricular myocardial fibers after myocardial infarction

Directory of Open Access Journals (Sweden)

Li Libin

2010-11-01

Full Text Available Abstract Background To explore the pathological changes of three-dimension structure of ventricular myocardial fibers after anterior myocardial infarction in dog heart. Methods Fourteen acute anterior myocardial infarction models were made from healthy dogs (mean weight 17.6 ± 2.5 kg. Six out of 14 dogs with old myocardial infarction were sacrificed, and their hearts were harvested after they survived the acute anterior myocardial infarction for 3 months. Each heart was dissected into ventricular myocardial band (VMB, morphological characters in infarction region were observed, and infarct size percents in descending segment and ascending segment were calculated. Results Six dog hearts were successfully dissected into VMB. Uncorresponding damages in myocardial fibers of descending segment and ascending segment were found in apical circle in anterior wall infarction. Infarct size percent in the ascending segment was significantly larger than that in the descending segment (23.36 ± 3.15 (SD vs 30.69 ± 2.40%, P = 0.0033; the long axis of infarction area was perpendicular to the orientation of myocardial fibers in ascending segment; however, the long axis of the infarction area was parallel with the orientation of myocardial fibers in descending segment. Conclusions We found that damages were different in both morphology and size in ascending segment and descending segment in heart with myocardial infarction. This may provide an important insight for us to understand the mechanism of heart failure following coronary artery diseases.

Asymptomatic myocardial ischemia following cold provocation

International Nuclear Information System (INIS)

Shea, M.J.; Deanfield, J.E.; deLandsheere, C.M.; Wilson, R.A.; Kensett, M.; Selwyn, A.P.

1987-01-01

Cold is thought to provoke angina in patients with coronary disease either by an increase in myocardial demand or an increase in coronary vascular resistance. We investigated and compared the effects of cold pressor stimulation and symptom-limited supine bicycle exercise on regional myocardial perfusion in 35 patients with stable angina and coronary disease and in 10 normal subjects. Regional myocardial perfusion was assessed with positron emission tomography and rubidium-82. Following cold pressor stimulation 24 of 35 patients demonstrated significant abnormalities of regional myocardial perfusion with reduced cation uptake in affected regions of myocardium: 52 +/- 9 to 43 +/- 9 (p less than 0.001 vs normal subjects). Among these 24 patients only nine developed ST depression and only seven had angina. In contrast, 29 of 35 patients underwent supine exercise, and abnormal regional myocardial perfusion occurred in all 29, with a reduction in cation intake from 48 +/- 10 to 43 +/- 14 (p less than 0.001 vs normal subjects). Angina was present in 27 of 29 and ST depression in 25 of 29. Although the absolute decrease in cation uptake was somewhat greater following cold as opposed to exercise, the peak heart rate after cold was significantly lower than that after exercise (82 +/- 12 vs 108 +/- 16 bpm, p less than 0.05). Peak systolic blood pressures after cold and exercise were similar (159 +/- 24 vs 158 +/- 28). Thus, cold produces much more frequent asymptomatic disturbances of regional myocardial perfusion in patients with stable angina and coronary disease than is suggested by pain or ECG changes

Noninvasive quantification of regional myocardial perfusion with rubidium-82 and positron emission tomography. Exploration of a mathematical model

International Nuclear Information System (INIS)

Herrero, P.; Markham, J.; Shelton, M.E.; Weinheimer, C.J.; Bergmann, S.R.

1990-01-01

Positron emission tomography (PET) centers without cyclotrons use generator-produced rubidium-82 (82Rb) for assessment of myocardial perfusion. The aim of the present study was to determine whether myocardial blood flow could be assessed quantitatively with 82Rb and PET. Because the myocardial extraction fraction of 82Rb varies inversely and nonlinearly with flow and cannot be measured conveniently with PET, we used an experimentally derived mathematical function defining the relation between single-pass extraction fraction of 82Rb and flow to obviate the necessity of measuring the extraction fraction directly. Myocardial blood flow in absolute terms (ml/g/min) was estimated from dynamic PET scans after intravenous administration of 82Rb in intact dogs and compared with flows measured with radiolabeled microspheres. In 36 comparisons in 13 dogs studied at rest, or after coronary occlusion, reperfusion, or after coronary hyperemia induced with intravenous dipyridamole, over the flow range from 0.2 to 2.0 ml/g/min, estimates of perfusion with rubidium correlated well with flows measured concomitantly with microspheres, although there was a slight underestimation of flow with rubidium (flow by 82Rb = 0.92 x flow by microspheres-0.021, r = 0.83). In general, estimates of flow in ischemic regions were less reliable than estimates for regions with normal flow. Thus, although the relation between myocardial extraction and retention of 82Rb and flow can vary under a variety of physiological and pathophysiological conditions, this study demonstrates the ability to obtain quantitative estimates of myocardial blood flow with 82Rb and PET under carefully defined conditions without measuring the extraction fraction directly

Nitrogen-13-labeled ammonia for myocardial imaging

Energy Technology Data Exchange (ETDEWEB)

Walsh, W.F.; Fill, H.R.; Harper, P.V.

1977-01-01

Cyclotron-produced nitrogen-13 (half-life 10 min), as labeled ammonia (/sup 13/NH/sub 4//sup +/), has been evaluated as a myocardial perfusion imaging agent. The regional myocardial uptake of /sup 13/NH/sub 4//sup +/ has been shown to be proportional to regional tissue perfusion in animal studies. Intravenously administered /sup 13/NH/sub 4//sup +/ is rapidly cleared from the circulation, being extracted by the liver (15 percent), lungs, myocardium (2 percent--4 percent), brain, kidney, and bladder. Myocardial ammonia is metabolized mainly to glutamine via the glutamine synthetase pathway. Pulmonary uptake is substantial, but usually transient, except in smokers where clearance may be delayed. The positron annihilation irradiation (511 keV) of /sup 13/N may be imaged with a scintillation camera, using either a specially designed tungsten collimator or a pinhole collimator. After early technical problems with collimation and the production method of /sup 13/NH/sub 4//sup +/ were overcome, reproducible high quality myocardial images were consistently obtained. The normal myocardial image was established to be of a homogeneous ''doughnut'' configuration. Imaging studies performed in patients with varying manifestations of ischemic and valvular heart disease showed a high incidence of localized perfusion defects, especially in patients with acute myocardial infarction. Sequential studies at short intervals in patients with acute infarction showed correlation between alterations in regional perfusion and the clinical course of the patient. It is concluded that myocardial imaging with /sup 13/NH/sub 4//sup +/ and a scintillation camera provides a valid and noninvasive means of assessing regional myocardial perfusion. This method is especially suitable for sequential studies of acute cardiac patients at short intervals. Coincidence imaging of the 511 keV annihilation irradiation provides a tomographic and potentially quantitative assessment of the

Tl myocardial SPECT demonstrates importance of collateral circulation in patients with myocardial infarction

International Nuclear Information System (INIS)

Hattori, Fukunori

1997-01-01

The influence of collateral circulation on the preservation of myocardial viability and the efficacy of drug therapy and PTCA were evaluated by exercise 201 Tl myocardial SPECT before and after treatment. Thirty-five patients with a history of myocardial infarction resulting from total or subtotal obstruction of the responsible coronary artery were divided into four groups, according to the method of the treatment and the degree of collateral blood flow. Patients in groups A and B received drug therapy and displayed developed and undeveloped collateral circulation, respectively. Groups C and D received PTCA and displayed developed and undeveloped collateral circulation, respectively. Tl myocardial SPECT was performed before treatment to record the extent of redistribution to the occluded region, the degree of myocardial viability and the nature and extent of the ischemic lesion. In group A, myocardial perfusion improved, although redistribution remained in all cases, while in group B, 4 of 7 cases improved after drug therapy. In group C, myocardial perfusion improved in all cases, and redistribution disappeared in 7 of 12 cases. 5 of 6 cases improved in group D after PTCA. After drug therapy, the %Tl uptake in the infarcted region improved significantly in initial and delayed images of patients in group A. The differences in initial and delayed images in group B before and after drug therapy were not significant. In contrast, groups C and D both registered significant improvement in initial and delayed images after PTCA. The washout rate improved significantly in groups A, C and D after their respective treatments. These results suggest that developed collateral circulation helps to preserve myocardial viability in cases of myocardial infarction. Myocardial perfusion improved after drug therapy in cases with developed collateral circulation, and in patients with developed and undeveloped collateral circulation receiving PTCA. (K.H.)

Studies on 201Th myocardial scintiscanning

International Nuclear Information System (INIS)

Buchner, U.

1979-01-01

The diagnostical evidence of myocardial scintiscanning with thallium-201 was tested on 98 patients with coronary heart disease. 2 mCi thallium-201 were injected into an arm vene and then scintigrams of the heart were registered partly with a scanner, partly with a gamma camera in several views. The healthy myocardium was found in the thallium-201-scintigram to be a rather homogeneous, horeshoe-shaped activity pattern with intramyocardial activity differences of up to 20% of the maximal thallium-201-activity above the myocard which can be declared to be physiological. In dependency on the local blood flow conditions, thallium-201 is stored only in the healthy, but not in the ischaemic or infarcted myocardium. In the scintigram, these regions are seen as regions with reduced radioactivity. A comparison of the localisation of the infarction in the scintigram with those in the electrocardiagram and coronary angiogram showed a good congrucucy. Scintigrams taken at different times after the infarction brought a decrease in the number of diagnosed storage failures, from 90% to 68% in infarctions older than 6 weeks. A scintigraphical differentiation between fresh and old infarctions was not possible. In cases of angiographically established coronary heart disease without infarction, pathological storage reductions were observed. By comparing the findings obtained by scintiscanning with the results of laevocardiography it was seen that hypokinetic regions in the thallium-201-myocardial scintigram showed in only 6% of the cases a pathological storage defect; akinetic, dyskinetic, and aneurysmatic regions, however, were seen in 65% of the cases as clear activity reductions or failures. (orig./MG) [de

Effect of collateral circulation on myocardial protection in patients with acute myocardial infarction. Comparison of technetium-99m-tetrofosmin myocardial single photon emission computed tomography and coronary angiography

International Nuclear Information System (INIS)

Yoshida, Michi; Kondo, Makoto; Abe, Yoshiteru; Kubota, Tomoyuki; Matsuoka, Ryota; Araki, Makoto; Tanio, Hitoshi; Doyama, Kiyoshi

2006-01-01

Evaluation of myocardial blood flow from collateral vessels into the infarct area has been estimated by coronary angiography. In patients with acute myocardial infarction with Thrombolysis in Myocardial Infarction (TIMI) 0 flow, myocardial tracer uptake on single photon emission computed tomography (SPECT) images can predict the collateral blood flow in the infarct area if technetium (Tc)-99m-tetrofosmin was administered before recanalization. The present study investigated whether collateral blood flow evaluated by myocardial scintigraphy is a good predictor of myocardial salvage in patients with acute myocardial infarction. The study group consisted of 30 patients (mean age 65±14 years, 23 males, 7 females) with first acute myocardial infarction and coronary angiography evidence of total occlusion (TIMI 0) within 12 hr after the onset. All patients had one vessel disease related to infarction and TIMI 3 flow after percutaneous coronary intervention (PCI). Tc-99m-tetrofosmin was injected intravenously before the PCI. The regional severity score index (RSSI) was obtained from SPECT using the 17 segment method with the four-point scoring system. Myocardial viability was evaluated by the RSSI obtained from thallium-glucose-insulin infusion SPECT after 1 week and regional wall motion score index obtained from echocardiography during the chronic phase. The patients were divided into two groups according to the angiographic collateral finding. There were no differences in RSSI on thallium-glucose-insulin SPECT and regional wall motion score between the good collateral group (n=8) and poor collateral group (n=22). Myocardial Tc-99m-tetrofosmin RSSI was similar in these groups. On the other hand, the patients were divided according to Tc-99m-tetrofosmin scintigraphic evaluation before PCI. RSSI on thallium-glucose-insulin SPECT was significantly greater (0.7±0.5 vs 1.5±0.4, p<0.01) and regional wall motion score was significantly less (1.46±0.50 vs 2.08±0.78, p<0

Limitations of regional myocardial thallium clearance for identification of disease in individual coronary arteries

International Nuclear Information System (INIS)

Becker, L.C.; Rogers, W.J. Jr.; Links, J.M.; Corn, C.

1989-01-01

The purpose of this study was to critically evaluate the usefulness of postexercise regional myocardial thallium-201 clearance for identifying disease in individual coronary arteries. Exercise and redistribution planar imaging studies were performed in 114 subjects, including 19 normal volunteers and 95 patients undergoing cardiac catheterization (70 with and 25 without greater than or equal to 50% narrowing in one or more coronary arteries). Thallium clearance was measured from predefined myocardial regions corresponding to the left anterior descending, left circumflex and right coronary arteries and was expressed as the percent decrease in activity at 4 h, assuming monoexponential clearance. In regions perfused by a normal or insignificantly diseased coronary artery, mean 4 h clearance was 58.9 +/- 9.4% for normal volunteers, 43.1 +/- 15.5% for catheterized patients without coronary artery disease and 36.3 +/- 24.9% for catheterized patients with coronary artery disease (p less than 0.001 patients with coronary artery disease versus normal volunteers). Clearance from normal regions was significantly associated with two measures of exercise performance: percent of predicted maximal heart rate achieved (r = 0.49) and exercise duration (r = 0.35). In regions perfused by a stenotic coronary artery, mean clearance was lower (31.1 +/- 19.8%) but was not significantly different from that in normal regions in the same patients. Clearance from diseased regions was also associated with maximal exercise heart rate (r = 0.28) and exercise duration (r = 0.41), but not with percent coronary artery stenosis (r = 0.02). After taking exercise performance into account, the number of diseased vessels or the presence or absence of disease in a given vessel had little influence on regional thallium clearance

Efficacy of coronary artery reconstruction in maintaining myocardial viability. Quntitative determination of local myocardial circulation with 13NH3 myocardial positron emission tomography

International Nuclear Information System (INIS)

Kobayashi, Satoshi; Takaba, Toshihiro; Kume, Masato; Kashima, Toshitaka; Michihata, Tetsuro.

1996-01-01

Thirty patients (280 areas) whose bypass grafts remained patent after surgical reconstruction of the coronary artery were examined. Before and after reconstruction, local myocardial blood circulation in infarcted regions and post-stenotic regions was measured by 13 NH 3 myocardial positron emission computed tomography (PET) at rest or during physical exercise in order to evaluate the efficacy of coronary artery reconstruction. Before operation, mean blood flow in post-stenotic regions (n=198) was 65±15 ml/min/100 g at rest and 85±23 ml/min/100 g during exercise. After coronary artery bypass grafting (CABG), mean blood flow was increased to 78±21 ml/min/100 g at rest (p, 0.01) and 105±32 ml/min/100 g during exercise (p<0.01). In infarcted regions (n=82), mean blood flow before operation was 51±23 ml/min/100 g at rest and 69±23 ml/min/100 g during exercise. After CABG, it increased to 62±19 ml/min/100 g at rest (p<0.01) and 81±29 ml/min/100 g during exercise (p<0.01). Thus, significant increases in blood flow were observed in both post-stenotic and infarcted regions at rest and physical exercise after operation. The regions of infarction were divided into three groups based on local myocardial blood flow at rest before operation: Group I: greater than 45 ml/min/100 g (n=35); Group II: less than 45 ml/min/100 g (n=30) but greater than 30 ml/min/100 g; and Group III: less than 30 ml/min/100 g (n=30). The efficacy of reconstruction was compared among these groups. The group with preoperative myocardial blood flow greater than 30 ml/min/100 g had increased blood flow after operation, indicating myocardial viability. (author)

Time course of regional myocardial glucose metabolism after transient ischemia assessed by positron emission tomography

Energy Technology Data Exchange (ETDEWEB)

Hoshizaki, Hiroshi (Gunma Univ., Maebashi (Japan). School of Medicine)

1992-11-01

The purpose of this study was to examine the significance of glucose metabolism in ischemic canine myocardium after reperfusion. Transient ischemia was induced by 90 or 180 minutes occlusion of the left anterior descending coronary artery. Twelve hours and 4 weeks after reperfusion, myocardial blood flow (MBF) and glucose metabolism were assessed (with H[sub 2][sup 15]O and [sup 18]F-FDG, respectively) by positron emission tomography (PET) under the fasting state, and the metabolic findings were compared with the histologic examination. Glucose metabolism in ischemic regions was inversely related to the amount of tissue necrosis 12 hours and 4 weeks after reperfusion (r=-0.89 and r=-0.82, respectively). The perfusion-metabolism mismatch pattern was seen in the area with less than 10 percent necrosis 12 hours after reperfusion, but this pattern disappeared after 4 weeks. The area with 10 to 50 percent necrosis showed the mismatch pattern until 4 weeks after reperfusion, and in the area with more than 50 percent necrosis, perfusion-metabolism concordantly decreased. Thus, metabolic index assessed early after reperfusion by PET identified myocardial viability, and the perfusion-metabolism mismatch pattern sustained in relation to the degree of ischemic injury. Since some regions estimated to be irreversible by PET were viable by the histologic examination, PET study might underestimate the myocardial viability. (author).

Usefulness of myocardial parametric imaging to evaluate myocardial viability in experimental and in clinical studies.

Science.gov (United States)

Korosoglou, G; Hansen, A; Bekeredjian, R; Filusch, A; Hardt, S; Wolf, D; Schellberg, D; Katus, H A; Kuecherer, H

2006-03-01

To evaluate whether myocardial parametric imaging (MPI) is superior to visual assessment for the evaluation of myocardial viability. Myocardial contrast echocardiography (MCE) was assessed in 11 pigs before, during, and after left anterior descending coronary artery occlusion and in 32 patients with ischaemic heart disease by using intravenous SonoVue administration. In experimental studies perfusion defect area assessment by MPI was compared with visually guided perfusion defect planimetry. Histological assessment of necrotic tissue was the standard reference. In clinical studies viability was assessed on a segmental level by (1) visual analysis of myocardial opacification; (2) quantitative estimation of myocardial blood flow in regions of interest; and (3) MPI. Functional recovery between three and six months after revascularisation was the standard reference. In experimental studies, compared with visually guided perfusion defect planimetry, planimetric assessment of infarct size by MPI correlated more significantly with histology (r2 = 0.92 versus r2 = 0.56) and had a lower intraobserver variability (4% v 15%, p < 0.05). In clinical studies, MPI had higher specificity (66% v 43%, p < 0.05) than visual MCE and good accuracy (81%) for viability detection. It was less time consuming (3.4 (1.6) v 9.2 (2.4) minutes per image, p < 0.05) than quantitative blood flow estimation by regions of interest and increased the agreement between observers interpreting myocardial perfusion (kappa = 0.87 v kappa = 0.75, p < 0.05). MPI is useful for the evaluation of myocardial viability both in animals and in patients. It is less time consuming than quantification analysis by regions of interest and less observer dependent than visual analysis. Thus, strategies incorporating this technique may be valuable for the evaluation of myocardial viability in clinical routine.

Regional myocardial perfusion in patients with atherosclerotic coronary artery disease, at rest and during angina pectoris induced by tachycardia

International Nuclear Information System (INIS)

Maseri, A.; L'Abbate, A.; Pesola, A.; Michelassi, C.; Marzilli, M.; De Nes, M.

1977-01-01

We studied regional myocardial perfusion by scintigraphic computer-assisted analysis of initial distribution, washout rates, and residual activity of 133 Xe injected into the left coronary artery of four patients with normal arteriograms and 14 patients with coronary stenosis. At rest, residual activity in poststenotic regions was always greater than in control regions, but initial washout rates were not slower. During angina, following xenon injections, the amount of indicator distributed to the poststenotic regions was markedly reduced; the increase of the initial washout rates was smaller than in control regions relative to rest, and residual activity was higher. Initial washout rates did not differ as much as from those of normal myocardium because in severe ischemia too little indicator is deposited initially in these regions to produce a change of any magnitude. Indeed, when angina was induced immediately after the xenon injection, poststenotic washout rates became much slower during angina than at rest, a finding that implicates functional factors in impairing poststenotic myocardial perfusion during angina

Analysis of acute myocardial infarction occurance in Saratov region using GIS-technologies and prognostic modeling

Directory of Open Access Journals (Sweden)

SokolovI.M.

2012-09-01

Full Text Available

The research objective: To find estimation tools of incidence of acute myocardial infarction at the regional level and to optimize organization of medical assistance to patients with acute coronary pathology. Materials. With the use of statistics of territorial distribution of acute myocardial infarction incidence in the region and GIS-TECHNOLOGIES the statistical analysis and mathematical modelling of the spatially-organizational data has been carried out. Results. On the basis of the received results the prognostic model of development of acute coronary pathology has been generated. Measures on optimization of organization of medical assistance to patients with an acute coronary pathology have been stated. Conclusion. Methods of intellectual support of the doctor may become effective in formation of organizational structure of the system of stage-by-stage qualified and specialized aid to patients with acute coronary syndrome.

Quantitative assessment of myocardial blood flow by measurement of fractional myocardial uptake of 201Tl

International Nuclear Information System (INIS)

Yonekura, Yoshiharu; Ishii, Yasushi; Torizuka, Kanji; Kadota, Kazunori; Kambara, Hirofumi

1980-01-01

Fractional Myocardial uptake of 201 Tl was measured for the quantitative assessment of myocardial blood flow in coronary artery disease (CAD). 10 normals and 28 CAD, 7 of which have less than 50% stenosis (CAD I) and 21 of which have more than 50% stenosis (CAD II) in the proximal portion of coronary arteries, were studied at rest and with submaximal exercise loading by bicycle ergometer. After intravenous injection of 201 Tl, its rapid transport process was recorded during the initial 5 minutes by a scintillation camera and a minicomputer. Total injected dosage (T) was obtained from the counts of the entire chest region during the initial passage of the tracer through the heart and lung. Myocardial uptake (M) was counted with the same geometry from the subsequent accumulation within the myocardial region with subtraction of the background activities in the upper mediastinal region (B). The fractional myocardial uptake of 201 Tl ((M-B)/T) is assumed to be proportional to the fractional myocardial blood flow to cardiac output (MBF/CO) according to the indicator fractionation principle. The average value of MBF/CO at rest in CAD (4.11 +- 1.12%) was significantly greater than in normals (3.36 +- 0.49%), which may be caused by an increased left ventricular mass in CAD. Change rate of MBF/CO on the exercise loading was significantly less in CAD I (1.36 +- 0.14) and in CAD II (1.11 +- 0.21) than in normals (1.75 +- 0.11). MBF/CO increased proportionally to the increment of the double product of heart rate and systolic blood pressure by exercise loading in normals, whereas it didn't in CAD. The sensitivity of this method was superior to the stress electrocardiogram and the stress myocardial perfusion imaging, not only in CAD II but also in CAD I. This result indicated that this type of global assessment of the myocardial reserve capacity is valuable in addition to the simple stress myocardial perfusion imaging. (author)

Quantitative aspects of myocardial perfusion imaging

International Nuclear Information System (INIS)

Vogel, R.A.

1980-01-01

Myocardial perfusion measurements have traditionally been performed in a quantitative fashion using application of the Sapirstein, Fick, Kety-Schmidt, or compartmental analysis principles. Although global myocardial blood flow measurements have not proven clinically useful, regional determinations have substantially advanced our understanding of and ability to detect myocardial ischemia. With the introduction of thallium-201, such studies have become widely available, although these have generally undergone qualitative evaluation. Using computer-digitized data, several methods for the quantification of myocardial perfusion images have been introduced. These include orthogonal and polar coordinate systems and anatomically oriented region of interest segmentation. Statistical ranges of normal and time-activity analyses have been applied to these data, resulting in objective and reproducible means of data evaluation

Myocardial ischemia and angina pectoris

International Nuclear Information System (INIS)

Selwyn, A.P.; Fox, K.M.; Jonathan, A.; Lavender, P.; Watson, I.

1981-01-01

Ambulatory monitoring of ST segment changes was performed in 60 patients presenting with angina, positive ECG stress tests and coronary artery disease, 85% of ischemic ECG events were asymptomatic, 37% occurred with no increase in heart rate and 15% of episodes either lasted 20 minutes or more or fluctuated in severity. A controlled pilot study in ten patients showed depression. Radionuclide studies in 50 patients with angina and coronary artery disease have shown that stress (i.e., atrial pacing) produced different patterns of disturbed regional myocardial perfusion related to the patient's exercise capacity and eventually leading to a decrease in regional myocardial perfusion during the ischemic episode. ST segment depression appeared only after the decrease in regional myocardial perfusion. These findings combined with past research suggest that patients with angina and coronary artery disease can suffer frequent asymptomatic disturbances of the regional myocardial perfusion. The frequency of these episodes and the time course for the recovery of the metabolic consequences mean that segments of ventricular myocardium may be constantly abnormal. The relative importance of changes in coronary tone and malfunction of platelets in the diseased coronary tree needs to be examined in clinical research. Pilot studies of antiplatelet agents have shown a significant beneficial effect on episodes of ischemia occurring at night and those occurring without any increase in heart rate. The techniques and observations in these patients with coronary artery disease all suggest that acute transient regional myocardial ischemia is caused by a variety of mechnisms. Further research using objective methods is required to discover the causes of ischemia and to rationalize treatment. (orig./MG) [de

Correlation between myocardial Thallium-201 kinetics, myocardial lactate metabolism and coronary angiographic findings in hypertrophic cardiomyopathy

International Nuclear Information System (INIS)

Hanrath, P.; Mathey, D.; Thiel, U.; Kupper, W.; Bleifeld, W.; Mantz, R.; Vorbringer, H.; Schneider, C.

1980-01-01

In 20 patients with idiopathic hypertrophic obstructive and nonobstructive cardiomyopathy (IHSS), biphasic Thallium-201 myocardial scintigraphy was performed. Regional myocardial Thallium-201 kinetics of these patients were analysed by a semiquantitative computerized method and compared with those of 6 normal subjects. In 12 of 18 with IHSS and no coronary artery disease 26 regions of interest with irreversible and 6 regions of interest with reversible Thallium-201 defects could be detected. Most of the Thallium-201 defects were localized in the interventricular septum. The defects were not related to the age of the patients and there was no relationship between the occurence of reversible Thallium-201 defects and pathological myocardial lactate extraction rate during maximal atrial pacing measured in 14 patients. The percentage (6.8%) of irreversible defect regions in patients with LV outflow obstruction at rest (n = 13) was more than twice higher compared to those (n = 5, 3.2%) without LV outflow obstruction or no provocative pressure gradient, resp. These data suggest that IHSS often associated with regional ischemic myocardial fibrosis despite normal coronary arteries. Therefore in these patients Thallium scintigraphy cannot be used as a noninvasive screening method to exclude or prove coronary artery disease. (orig.) [de

Assessment of regional myocardial blood flow with N-13 ammonia PET

International Nuclear Information System (INIS)

Himi, Toshiharu

1992-01-01

Regional myocardial blood flow (RMBF) has been assessed with O-15 water, O-15 CO 2 and N-13 ammonia in Japan, and O-15 water has been used most commonly for quantitative measurement of RMBF with Iida's method. Though myocardial image quality with N-13 ammonia is superior to that with O-15 water or that with O-15 CO 2 , RMBF was not assessed quantitatively with N-13 ammonia. We have attempted to assess RMBF non-invasively with N-13 ammonia and dynamic PET. Yoshida et. al applied the first-pass flow model to N-13 ammonia dynamic PET for measurement of RMBF. We could measure RMBF of the patients with hypertrophic cardiomyopathy (HCM) and could assess effects of vaso-dilating agents on RMBF non-invasively with this method. But this method dose not take account of cross-contamination of recorded counts between myocardium and surrounding tissues, and hence we have applied factor analysis to dynamic PET for correction of that. It was suggested that cross-contamination in normal cases could be corrected by the factor analysis and there were few cross-contamination in the patients with HCM. (author)

Simultaneous estimates of regional myocardial blood flow and metabolism by the developing chick heart using [201]thallium and [14C] 2-deoxyglucose autoradiography

International Nuclear Information System (INIS)

Kostreva, D.R.; Wood, J.D.

1990-01-01

Little is known about regional myocardial blood flow and metabolism in the developing heart. Simultaneous estimates of regional myocardial blood flow and glucose metabolism have been made in the adult rat by Yonekura et al using [ 201 ] Thallium (THAL) and [ 14 C]2-deoxyglucose (DG) autoradiography. Since glucose is the primary cardiac metabolic substrate during development, glucose utilization is also an estimate of myocardial metabolism. Examination and comparison of the THAL and DG autoradiographs revealed that there is an uncoupling of blood flow and metabolism in the developing chick heart. Areas of the heart which had marked glucose utilization did not always have marked blood flow. Regions of the heart which had marked blood flow but very little glucose utilization were the interventricular septum and the apex. One explanation for this disparity is that although blood flow may be established in these regions, normal cardiac function requiring significant substrate utilization may not be fully developed

Assessment of myocardial perfusion and metabolism for assessment of myocardial viability

International Nuclear Information System (INIS)

Beller, G.

1996-01-01

Identifying preserved myocardial viability in the presence of severe regional left ventricular dysfunction is becoming increasingly more important for clinical decision-making to better select those patients with coronary artery disease who will benefit most from revascularization. 201 Tl remains the most commonly employed radionuclide for detecting both ischemia and viability. A severe persistent defect with 201 Tl uptake compared to peak to improved perfusion and corresponding improved function after revascularisation. Detection of defect reversibility on 201 Tl imaging is enhanced by 'reinjection' of a second 201 Tl dose after acquisition of redistribution images. Initial and 4-hour rest/redistribution imaging has proven most usefull for detection of viability in the resting state in patients with ischemic cardiomyopathy. The greater the extent of preoperative viability, the greater is the improvement in regional and global function after revascularisation. 99 Tc sestamibi has also been demonstrated to be extracted by myocardial cells in proportion to regional blood flow in the presence of viable myocities. Although this agrnt does not redistribute after intravenous injection, its >50% uptake of the tracer implies viablility and predicts improved regional function after revascularisation. Finally positron emission tomography with 18 F fluorodeoxoglucose (FDG) is perhaps the most sensitive noninvasive imaging technique for detection of viability in stunned or hibernating myocardium. A mismatch pattern between regional flow and FDG uptake as approximately an 80-85% positive preicted value for predicting improved function in asynergic myocardial regions after revascualarisation

Repeatability of regional myocardial blood flow calculation in 82Rb PET imaging

International Nuclear Information System (INIS)

Knešaurek, Karin; Machac, Josef; Zhang, Zhuangyu

2009-01-01

We evaluated the repeatability of the calculation of myocardial blood flow (MBF) at rest and pharmacological stress, and calculated the coronary flow reserve (CFR) utilizing 82 Rb PET imaging. The aim of the research was to prove high repeatability for global MBF and CFR values and good repeatability for regional MBF and CFR values. The results will have significant impact on cardiac PET imaging in terms of making it more affordable and increasing its use. 12 normal volunteers were imaged at rest and during pharmacological stress, with 2220 MBq of 82 Rb each. A GE Advance PET system was used to acquire dynamic 50-frame studies. MBF was calculated with a 2-compartmental model using a modified PMOD program (PMOD; University Hospital Zurich, Zurich, Switzerland). Two differential equations, describing a 2-compartmental model, were solved by numerical integration and using Levenberg-Marquardt's method for fitting data. The PMOD program defines 16 standard segments and calculates myocardial flow for each segment, as well as average septal, anterior, lateral, inferior and global flow. Repeatability was evaluated according to the method of Bland and Altman. Global rest and stress MBF, as well as global CFR, showed very good repeatability. No significant differences were found between the paired resting global MBF (0.63 ± 0.13 vs. 0.64 ± 0.13 mL/min/g; mean difference, -1.0% ± 2.6%) and the stress global MBF (1.37 ± 0.23 vs. 1.37 ± 0.24; mean difference, 0.1% ± 2.3%). Global CFR was highly reproducible (2.25 ± 0.56 vs. 2.22 ± 0.54, P = not statistically significant; mean difference, 1.3% ± 14.3%). Repeatability coefficients for global rest MBF were 0.033 (5.2%) and stress MBF 0.062 (4.5%) mL/min/g. Regional rest and stress MBF and CFR have shown good reproducibility. The average per sector repeatability coefficients for rest MBF were 0.056 (8.5%) and stress MBF 0.089 (6.3%) mL/min/g, and average repeatability coefficient for CFR was 0.25 (10.6%). The results

Theoretical considerations in measurement of time discrepancies between input and myocardial time-signal intensity curves in estimates of regional myocardial perfusion with first-pass contrast-enhanced MRI.

Science.gov (United States)

Natsume, Takahiro; Ishida, Masaki; Kitagawa, Kakuya; Nagata, Motonori; Sakuma, Hajime; Ichihara, Takashi

2015-11-01

The purpose of this study was to develop a method to determine time discrepancies between input and myocardial time-signal intensity (TSI) curves for accurate estimation of myocardial perfusion with first-pass contrast-enhanced MRI. Estimation of myocardial perfusion with contrast-enhanced MRI using kinetic models requires faithful recording of contrast content in the blood and myocardium. Typically, the arterial input function (AIF) is obtained by setting a region of interest in the left ventricular cavity. However, there is a small delay between the AIF and the myocardial curves, and such time discrepancies can lead to errors in flow estimation using Patlak plot analysis. In this study, the time discrepancies between the arterial TSI curve and the myocardial tissue TSI curve were estimated based on the compartment model. In the early phase after the arrival of the contrast agent in the myocardium, the relationship between rate constant K1 and the concentrations of Gd-DTPA contrast agent in the myocardium and arterial blood (LV blood) can be described by the equation K1={dCmyo(tpeak)/dt}/Ca(tpeak), where Cmyo(t) and Ca(t) are the relative concentrations of Gd-DTPA contrast agent in the myocardium and in the LV blood, respectively, and tpeak is the time corresponding to the peak of Ca(t). In the ideal case, the time corresponding to the maximum upslope of Cmyo(t), tmax, is equal to tpeak. In practice, however, there is a small difference in the arrival times of the contrast agent into the LV and into the myocardium. This difference was estimated to correspond to the difference between tpeak and tmax. The magnitudes of such time discrepancies and the effectiveness of the correction for these time discrepancies were measured in 18 subjects who underwent myocardial perfusion MRI under rest and stress conditions. The effects of the time discrepancies could be corrected effectively in the myocardial perfusion estimates. Copyright © 2015 Elsevier Inc. All rights

Reversible myocardial ischaemia or irreversible myocardial fibrosis

International Nuclear Information System (INIS)

Mathey, D.; Hanrath, P.; Kupper, W.; Bleifeld, W.; Montz, R.; Knop, J.; Stritzke, P.; Kroeger, E.; Bleese, N.

1978-01-01

The results of biphasis 201 thallium ( 201 Tl) scanning were compared with those of coronary arteriography, left ventricular angiography and stress ECG in 56 patients with coronary artery disease and six with no evidence of heart disease. There were 104 201 Tl defects, 50 of them reversible. The defects were always located in the area supplied by a critically stenotic coronary artery. Correlation of regional wall motion with 201 Tl activity demonstrated that in all forms of abnormal wall motion there was either ischaemia or fibrosis. The resting LV angiogram thus does not make it possible to distinguish between myocardial ischaemia and fibrosis. Taking the LV angiogram as a standard, the rate of false-positive 201 Tl scintigrams was 5%, that of false-negative ones 23%. The biphasic 201 Tl scintigram was more sensitive than the stress ECG in detecting myocardial ischaemia. It furthermore made it possible to localize the ischaemic (or fibrotic) region within the LV and to estimate its size. (orig.) [de

Criteria for definition of regional functional improvement on quantitative post-stress gated myocardial SPET after bypass surgery in patients with ischaemic cardiomyopathy

International Nuclear Information System (INIS)

Lee, Dong Soo; Cheon, Gi Jeong; Paeng, Jin Chul; Chung, June-Key; Lee, Myung Chul; Kim, Ki Bong

2002-01-01

Myocardial viability can be defined as functional improvement of dysfunctional myocardium after revascularization. The purpose of this study was to define the optimal criteria for definition of regional functional improvement after coronary artery bypass graft (CABG) surgery on quantitative gated single-photon emission tomography (SPET). Thirty-two patients (26 men, 6 women; age 56±13 years) with coronary artery disease (three-vessel disease, 17; two-vessel disease, 15; previous history of myocardial infarction, 9) and severe left ventricular dysfunction (LVEF≤35%) underwent CABG. Rest thallium-201/dipyridamole stress technetium-99m methoxyisobutylisonitrile gated myocardial SPET was performed before and 3 months after CABG. Global LV functional improvement was defined as either an improvement in LVEF of 10% (n=15) or an improvement in LVEF of 5% combined with a decrease in end-systolic volume of 10 ml (n=2) after CABG on quantitative gated SPET. Postoperative regional wall thickening improvement (ΔRWT), regional wall motion improvement (ΔRWM) and regional resting (ΔRP) and stress perfusion improvement (ΔRstrP) were used to determine global functional improvement by ROC curve analysis, and the optimal criteria for definition of viable regional dysfunctional myocardium were defined on the ROC curves. Correlations were verified by determining the number of improved myocardial regions and LVEF improvement. LVEF was improved from 25%±6% to 34%±11% after CABG. A total of 229 segments were dysfunctional (wall motion ≤2 mm, thickening ≤20%) before CABG. On ROC curve analysis using global functional improvement as an indicator of viability, the areas under the ROC curves (AUCs) of ΔRWT and ΔRWM were 0.717 and 0.620, respectively. The AUC of ΔRWT was significantly larger than that of ΔRWM (P=0.009) and the optimal cut-off value of ΔRWT was 15%. The AUCs of ΔRP and ΔRstrP were not significant. The correlation coefficients between summed ΔRWT and �

Experimental and clinical study of cardiac hypertrophy by thallium-201 myocardial scintigraphy

International Nuclear Information System (INIS)

Torii, Yukio

1983-01-01

I studied experimentally the myocardial uptake of 201 Tl in cardiac hypertrophy in rat, and clinically evaluated cardiac shape and dimension in the patients with various types of cardiac hypertrophy. Experimentally, both myocardial blood flow (MBF) and Tl uptake were increased with cardiac weight. There were negative correlations between the extraction fraction and MBF. Tl uptake in Hypertrophy is not always dependent on MBF and affected by the altered metabolism of hypertrophied myocardium. Clinical study was performed in 29 normal subjects and in 90 patients with heart disease. The measurements of left ventricular (LV) size by Tl scintigraphy were well correlated with them by echocardiography. Aortic stenosis and hypertensive heart disease showed thick wall and spherical shape. Both mitral (MR) and aortic (AR) regurgitation showed ventricular dilatation, spherical shape (in chronic MR) and ellipsoid shape (in acute MR and in AR). Decreased ventricular size but normal shape was observed in mitral stenosis and cor pulmonale. Hypertrophic cardiomyopathy showed thick wall with asymmetric septal hypertrophy, while congestive cardiomyopathy showed thin wall with marked ventricular dilatation and spherical shape. I conclude that heart disease has characteristic figures in dimension and shape which may be reflecting cardiac performance or compensating for the load to the heart, and that 201 Tl scintigraphy is useful evaluating cardiac morphology as well as in diagnosing myocardial ischemia. (J.P.N.)

Atlas-based analysis of cardiac shape and function: correction of regional shape bias due to imaging protocol for population studies.

Science.gov (United States)

Medrano-Gracia, Pau; Cowan, Brett R; Bluemke, David A; Finn, J Paul; Kadish, Alan H; Lee, Daniel C; Lima, Joao A C; Suinesiaputra, Avan; Young, Alistair A

2013-09-13

Cardiovascular imaging studies generate a wealth of data which is typically used only for individual study endpoints. By pooling data from multiple sources, quantitative comparisons can be made of regional wall motion abnormalities between different cohorts, enabling reuse of valuable data. Atlas-based analysis provides precise quantification of shape and motion differences between disease groups and normal subjects. However, subtle shape differences may arise due to differences in imaging protocol between studies. A mathematical model describing regional wall motion and shape was used to establish a coordinate system registered to the cardiac anatomy. The atlas was applied to data contributed to the Cardiac Atlas Project from two independent studies which used different imaging protocols: steady state free precession (SSFP) and gradient recalled echo (GRE) cardiovascular magnetic resonance (CMR). Shape bias due to imaging protocol was corrected using an atlas-based transformation which was generated from a set of 46 volunteers who were imaged with both protocols. Shape bias between GRE and SSFP was regionally variable, and was effectively removed using the atlas-based transformation. Global mass and volume bias was also corrected by this method. Regional shape differences between cohorts were more statistically significant after removing regional artifacts due to imaging protocol bias. Bias arising from imaging protocol can be both global and regional in nature, and is effectively corrected using an atlas-based transformation, enabling direct comparison of regional wall motion abnormalities between cohorts acquired in separate studies.

Exercise-induced ST-segment depression and myocardial ischemia in patients with hypertrophic cardiomyopathy. Myocardial scintigraphic study

International Nuclear Information System (INIS)

Miyai, Nobuyuki; Kawasaki, Tatsuya; Taniguchi, Takuya; Kamitani, Tadaaki; Kawasaki, Shingo; Sugihara, Hiroki

2005-01-01

Patients with hypertrophic cardiomyopathy (HCM) sometimes develop myocardial ischemia during exercise in the absence of coronary lesions. The relationship between myocardial ischemia and ST-segment depression was investigated during exercise testing in patients with HCM. Regional hypoperfusion and/or transient left ventricular cavity dilation, a parameter of subendocardial hypoperfusion, were assessed on exercise 99 m Tc-tetrofosmin myocardial scintigraphy in 42 patients with non-obstructive HCM. The scintigraphic results were further correlated with the ST-segment responses to exercise. Regional hypoperfusion or transient left ventricular cavity dilation were observed in 19 (45%) or 16 (38%) patients with HCM, respectively. The incidence of ST-segment depression ≥0.1 mV during exercise testing was similar in HCM patients with regional hypoperfusion, with transient left ventricular cavity dilation, and without hypoperfusion (42%, 38%, 38%, p=0.95). Furthermore, exercise-induced ST-segment depression ≥0.1 mV occurred similarly irrespective of symptoms, exercise tolerance, the degree or the site of hypertrophy, or the presence or absence of resting ST-segment depression. ST-segment depression during exercise testing was common in patients with HCM, but seems to be an unreliable marker of myocardial ischemia as assessed by exercise scintigraphy. (author)

Myocardial scintigraphy

International Nuclear Information System (INIS)

Bunko, Hisashi; Hisada, Kinichi

1982-01-01

Among the various methods of image diagnosis of the cardiovascular disorder, nuclear cardiology provides noninvasive means for evaluation of myocardial perfusion as well as morphological and functional informations. In this article, clinical application and image diagnosis of myocardial scintigraphy including Tl-201 myocardial perfusion scintigraphy, single photon emission computed tomography with Tl-201, acute myocardial infarction scintigraphy with Tc-99m-pyrophosphate and Ga-67 imaging of the heart, were discussed. Multiplanar imaging of the heart with Tl-201 after stress and at redistribution was the accepted method for detection and evaluation of the ischemic heart disease. Although it achieved high sensitivity and specificity for ischemic heart disease, detection of the small ischemia and quantation of the regional Tl-201 accumulation were difficult with conventional multiplanar imaging. Application of emission computed tomography improved detectability and quantitativity of the ischemia. However, 7-pinhole tomography did not increase the diagnostic accuracy significantly. It had limited clinical applicability due to poor quantitativity in spite of improved image contrast and its tomographic nature. Advantage and limitation of these tomographic imaging and multiplanar imaging were discussed. Problems and prognostic significance of pyrophosphate imaging of the acute myocardial infarction were also discussed. Visualization of the heart with Ga-67 was helpful for identification of the tumor or inflammation of the heart as well as evaluation of the effect of the therapy. (author)

Trends in Regionalization of Care for ST-Segment Elevation Myocardial Infarction

Directory of Open Access Journals (Sweden)

Renee Y. Hsia

2017-09-01

Full Text Available Introduction: California has led successful regionalized efforts for several time-critical medical conditions, including ST-segment elevation myocardial infarction (STEMI, but no specific mandated protocols exist to define regionalization of care. We aimed to study the trends in regionalization of care for STEMI patients in the state of California and to examine the differences in patient demographic, hospital, and county trends. Methods: Using survey responses collected from all California emergency medical services (EMS agencies, we developed four categories – no, partial, substantial, and complete regionalization – to capture prehospital and inter-hospital components of regionalization in each EMS agency’s jurisdiction between 2005–2014. We linked the survey responses to 2006 California non-public hospital discharge data to study the patient distribution at baseline. Results: STEMI regionalization-of-care networks steadily developed across California. Only 14% of counties were regionalized in 2006, accounting for 42% of California’s STEMI patient population, but over half of these counties, representing 86% of California’s STEMI patient population, reached complete regionalization in 2014. We did not find any dramatic differences in underlying patient characteristics based on regionalization status; however, differences in hospital characteristics were relatively substantial. Conclusion: Potential barriers to achieving regionalization included competition, hospital ownership, population density, and financial challenges. Minimal differences in patient characteristics can establish that patient differences unlikely played any role in influencing earlier or later regionalization and can provide a framework for future analyses evaluating the impact of regionalization on patient outcomes.

Regional myocardial blood flow, metabolism and function assessed noninvasively by positron emission tomography

Energy Technology Data Exchange (ETDEWEB)

Schelbert, H.R.; Phelps, M.E.; Hoffman, E.; Huang, S.; Kuhl, D.E.

1979-01-01

Positron emission computed tomography is a new technique for the noninvasive measure of myocardial blood flow, mechanical function and, in particular, metabolism. The capability of this new study means is due to the technological innovations of the imaging device and the availability of radioactive tracers that are specific for blood flow and metabolism. The device permits recording of cross-sectional images of the left ventricular myocardium that reflect quantitatively regional tracer tissue concentrations. By employing tracer kinetic models this new technique permits the measurement of regional glucose and fatty acid metabolism of the heart. While already an important new tool for investigative studies into cardiac physiology and pathophysiology, the clinical utility of positron emission tomography remains to be defined.

Regional myocardial blood flow, metabolism and function assessed noninvasively by positron emission tomography

International Nuclear Information System (INIS)

Schelbert, H.R.; Phelps, M.E.; Hoffman, E.; Huang, S.; Kuhl, D.E.

1979-01-01

Positron emission computed tomography is a new technique for the noninvasive measure of myocardial blood flow, mechanical function and, in particular, metabolism. The capability of this new study means is due to the technological innovations of the imaging device and the availability of radioactive tracers that are specific for blood flow and metabolism. The device permits recording of cross-sectional images of the left ventricular myocardium that reflect quantitatively regional tracer tissue concentrations. By employing tracer kinetic models this new technique permits the measurement of regional glucose and fatty acid metabolism of the heart. While already an important new tool for investigative studies into cardiac physiology and pathophysiology, the clinical utility of positron emission tomography remains to be defined

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

International Nuclear Information System (INIS)

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

2004-01-01

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

Myocardial scintigraphy with /sup 201/Tl and quantitative assessment of myocardial blood flow

Energy Technology Data Exchange (ETDEWEB)

Ishii, Y; Kanbara, H; Yonekura, Y; Kadota, K; Fujita, T [Kyoto Univ. (Japan). Faculty of Medicine

1976-12-01

A newly introduced radionuclide for myocardial imaging, /sup 201/Tl, was studied. Twenty-two subjects consisting of 7 normals, 12 with ischemic heart disease and 3 with hypertrophic cardiomyopathy (HCM) were selected. On intravenous administration of /sup 201/Tl(1.5 to 20. mCi), initial transit of the tracer through the heart, as well as subsequent uptake by the myocardium, were recorded by a scintillation camera. The later process showed the distribution of the myocardial blood flow (MBF). A normal myocardial scintigraphy revealed the left-sided myocardial mass predominantly, whereas the right side or the septum predominated in the case of tetralogy of fallot (T/F) or idiopathic hypertrophic subuaortic stenosis (IHSS). An ischemic or infarcted area of the myocardium in ischemic heart disease (IHD) was compatible with electrocardiographic findings, and revealed defects even in an equivocal case on ECG. Since the ratio of radioactivity taken up by the myocardium (U) to the total injected dosis (I) is assumed to be proportional to the fractional MBF of cardiac output (CO), MBF/CO is calculated by ratio of the radioactivity selected from myocardial region on the later recording to that from the entire region on the initial transit of the tracer bolus. The average MBF/CO of normals was 4.4 +- 0.5%, IHD 4.0 +- 0.8% and HCM 5.5 +- 1.2%. On exercise loading, a significant increase of this value was observed in normals, whereas no change was observed in IHD.

Reverse redistribution phenomenon on rest 99mTc-tetrofosmin myocardial single photon emission computed tomography involves impaired left ventricular contraction in patients with acute myocardial infarction

International Nuclear Information System (INIS)

Kurokawa, Kazuyuki; Ohte, Nobuyuki; Miyabe, Hiromichi; Akita, Sachie; Yajima, Kazuhiro; Hayano, Junichiro; Kimura, Genjiro

2003-01-01

The purpose of this study was to investigate the clinical significance of the reverse redistribution (RR) phenomenon on technetium-99m ( 99m Tc)-tetrofosmin myocardial single photon emission computed tomography (SPECT) performed at rest. Twenty-five patients underwent myocardial SPECT 3 weeks after the onset of acute myocardial infarction. Myocardial images were acquired at 40 min (early) and 4 h (delayed) after the injection of 740 MBq of 99m Tc-tetrofosmin. The regional myocardial uptake of the tracer in 26 segments of the left ventricular (LV) wall was visually scored from 0 (no activity) to 3 (normal activity), and then the RR was defined as a decrease of more than 1 point in the activity score on the delayed image compared with that on the early image. Regions with an activity score of 3 on both the early and delayed images were defined as normal, and those with a score of 0 or 1 on the early image were considered to have a fixed defect. The regional myocardial 99m Tc-tetrofosmin uptake and washout rate were also quantitatively assessed in each region. In addition, exercise stress electrocardiograph-gated SPECT with 99m Tc-tetrofosmin was performed within 1 week of the rest study, and the percent count increase (%CI) during myocardial contraction in each corresponding region was studied. RR was observed in 18 of the 25 patients. The regional washout rate of 99m Tc-tetrofosmin was significantly higher in the RR regions (45.0±3.8%) than in either the normal regions (36.4±4.1%, p 99m Tc-tetrofosmin SPECT have severely impaired LV wall contraction after exercise. (author)

Image based cardiac acceleration map using statistical shape and 3D+t myocardial tracking models; in-vitro study on heart phantom

Science.gov (United States)

Pashaei, Ali; Piella, Gemma; Planes, Xavier; Duchateau, Nicolas; de Caralt, Teresa M.; Sitges, Marta; Frangi, Alejandro F.

2013-03-01

It has been demonstrated that the acceleration signal has potential to monitor heart function and adaptively optimize Cardiac Resynchronization Therapy (CRT) systems. In this paper, we propose a non-invasive method for computing myocardial acceleration from 3D echocardiographic sequences. Displacement of the myocardium was estimated using a two-step approach: (1) 3D automatic segmentation of the myocardium at end-diastole using 3D Active Shape Models (ASM); (2) propagation of this segmentation along the sequence using non-rigid 3D+t image registration (temporal di eomorphic free-form-deformation, TDFFD). Acceleration was obtained locally at each point of the myocardium from local displacement. The framework has been tested on images from a realistic physical heart phantom (DHP-01, Shelley Medical Imaging Technologies, London, ON, CA) in which the displacement of some control regions was known. Good correlation has been demonstrated between the estimated displacement function from the algorithms and the phantom setup. Due to the limited temporal resolution, the acceleration signals are sparse and highly noisy. The study suggests a non-invasive technique to measure the cardiac acceleration that may be used to improve the monitoring of cardiac mechanics and optimization of CRT.

Regional myocardial extraction of a radioiodinated branched chain fatty acid during right ventricular pressure overload due to acute pulmonary hypertension

International Nuclear Information System (INIS)

Hurford, W.; Lowenstein, E.; Zapol, W.; Barlai-Kovach, M.; Livni, E.; Elmaleh, D.R.; Strauss, H.W.

1985-01-01

To determine whether branched chain fatty acid extraction is reduced during right ventricular (RV) dysfunction due to acute pulmonary artery hypertension, studies were done in 6 anesthetized dogs. Regional branched chain fatty acid extraction was measured by comparing the myocardial uptake of I-125 labeled 15-[p-(iodophenyl)]-3-methylpentadecanoic acid (I-PDA) to myocardial blood flow. Acute pulmonary hypertension was induced by incremental intravenous injection of 100 micron diameter glass beads into six pentobarbital anesthetized, mechanically ventilated dogs. Myocardial blood flow was measured by radiolabeled microspheres both under baseline conditions and during pulmonary hypertension. Mean RV pressure rose from 12 +- 2 (mean +- SEM) to 30 +-3mmHg resulting in a 225 +- 16% increase in RV stroke work. RV ejection fraction, as assessed by gated blood pool scans fell from 39 +- 2 to 18 +- 2%. Left ventricular (LV) pressures, stroke work and ejection fraction were unchanged. Myocardial blood flow increased 132 + 59% in the RV free wall and 67 +- 22% in the RV septum. LV blood flow was unchanged. Despite increased RV work and myocardial blood flow, no differences were noted in the branched chain fatty acid extraction ratios among LV or RV free walls or septum. The authors conclude that early RV dysfunction associated with pulmonary artery hypertension is not due to inadequate myocardial blood flow or branched chain fatty acid extraction

Role of myocardial perfusion imaging in evaluating thrombolytic therapy for acute myocardial infarction

International Nuclear Information System (INIS)

Beller, G.A.

1987-01-01

Myocardial thallium-201 scintigraphy is being increasingly employed as a method for assessing the efficacy of coronary reperfusion in acute myocardial infarction. New thallium uptake after intracoronary tracer administration after successful recanalization indicates that nutrient blood flow has been successfully restored. One may also presume that some myocardial salvage occurred if thallium administered in this manner is transported intracellularly by myocytes with intact sarcolemmal membranes. However, if one injects thallium by way of the intracoronary route immediately after reperfusion, the initial uptake of thallium in reperfused myocardium may predominantly represent hyperemic flow and regional thallium counts measured may not be proportional to the mass of viable myocytes. When thallium is injected intravenously during the occlusion phase the degree of redistribution after thrombolysis is proportional to the degree of flow restoration and myocardial viability. When thallium is injected for the first time intravenously immediately after reperfusion, an overestimation of myocardial salvage may occur because of excess thallium uptake in the infarct zone consequent to significant hyperemia. Another approach to myocardial thallium scintigraphy in patients undergoing thrombolytic therapy is to administer two separate intravenous injections before and 24 hours or later after treatment. Finally, patients with acute myocardial infarction who receive intravenous thrombolytic therapy are candidates for predischarge exercise thallium-201 scintigraphy for risk stratification and detection of residual ischemia

T1 mapping of the myocardium: Intra-individual assessment of the effect of field strength, cardiac cycle and variation by myocardial region

Directory of Open Access Journals (Sweden)

Kawel Nadine

2012-05-01

Full Text Available Abstract Background Myocardial T1 relaxation time (T1 time and extracellular volume fraction (ECV are altered in the presence of myocardial fibrosis. The purpose of this study was to evaluate acquisition factors that may result in variation of measured T1 time and ECV including magnetic field strength, cardiac phase and myocardial region. Methods 31 study subjects were enrolled and underwent one cardiovascular MR exam at 1.5 T and two exams at 3 T, each on separate days. A Modified Look-Locker Inversion Recovery (MOLLI sequence was acquired before and 5, 10, 12, 20, 25 and 30 min after administration of 0.15 mmol/kg gadopentetate dimeglumine (Gd-DTPA; Magnevist at 1.5 T (exam 1. For exam 2, MOLLI sequences were acquired at 3 T both during diastole and systole, before and after administration of Gd-DTPA (0.15 mmol/kg Magnevist.Exam 3 was identical to exam 2 except gadobenate dimeglumine was administered (Gd-BOPTA; 0.1 mmol/kg Multihance. T1 times were measured in myocardium and blood. ECV was calculated by (ΔR1myocardium/ΔR1blood*(1-hematocrit. Results Before gadolinium, T1 times of myocardium and blood were significantly greater at 3 T versus 1.5 T (28% and 31% greater, respectively, p  Conclusion ECV is similar at field strengths of 1.5 T and 3 T. Due to minor variations in T1 time and ECV during the cardiac cycle and in different myocardial regions, T1 measurements should be obtained at the same cardiac phase and myocardial region in order to obtain consistent results.

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

Energy Technology Data Exchange (ETDEWEB)

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

1992-07-01

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

Regional myocardial blood flow distribution during intracoronary infusion of parathyroid hormone

International Nuclear Information System (INIS)

Crass, M.F. III; Lust, R.M.

1986-01-01

Although low doses of the biologically-active fragment of parathyroid hormone PTH-(1-34), have been shown to produce potent dilation of the coronary circulation specific regional and transmural (endo/epi) myocardial blood flow (MBF) responses to the hormone have not been described. Anesthetized open-chest mongrel dogs were instrumented to quantitate coronary blood flow and other cardiodynamic parameters. PTH-(1-34) was infused into the left circumflex artery (.008 nmol kg -1 min -1 ). Using the reference withdrawal method, radionuclide-labeled microspheres were injected before (basal flow), during (8 min after new steady-state flow), and after (restoration of basal flow) a 20 min infusion of PTH-(1-34). MFB increased from 76 +- 1.9 to 152 +- 3.5 ml min -1 100 g -1 (P < .001) during PTH-(1-34) infusion. No differences in endo/epi flow ratio or regional coronary blood flow within the left ventricle were detected. Thus, in anesthetized dogs, the increase in MBF observed secondary to the PTH-(1-34)-induced decrease in coronary resistance appeared to be uniform transmurally and regionally, and is probably not the result of a shunting or steal phenomenon

Regional myocardial oxygen consumption determined noninvasively in humans with [1-11C]acetate and dynamic positron tomography

International Nuclear Information System (INIS)

Armbrecht, J.J.; Buxton, D.B.; Brunken, R.C.; Phelps, M.E.; Schelbert, H.R.

1989-01-01

Experimental studies of animals have previously demonstrated the validity of [1-11C]acetate as a tracer of oxidative metabolism for use with positron emission tomography. The present study was undertaken to define in normal human volunteers the relation between myocardial clearance kinetics of [1-11C]acetate, and the rate-pressure product as an index of myocardial oxygen consumption. Twenty-two studies were performed of 12 volunteers. The rate-pressure product was increased with continuous supine bicycle exercise in six studies. Of the 16 resting studies, seven were performed in the fasted state and nine following an oral glucose load, to define possible effects of substrate availability on the tracer-tissue kinetics. Myocardial tissue time-activity curves were biexponential. Clearance of activity was homogeneous throughout the myocardium. The rate constants k1, obtained from biexponential fitting, and kmono, obtained by monoexponential fitting of the initial linear portion of the time-activity curves, correlated well with the rate-pressure product. Although the correlation coefficient was higher for k1 than for kmono (0.95 vs. 0.91), analysis on a sectorial basis showed less regional variability in kmono. This suggests that kmono, which is more practical than k1 because it requires shorter acquisition times, may be more clinically and experimentally useful for detection of myocardial segments with abnormal oxygen consumption. Overall, changes in myocardial substrate supply were without significant effect on the relation between the rate constants (k1 and kmono) and the rate-pressure product, although a small decrease in kmono/rate-pressure product was observed following oral glucose by paired analysis in four subjects

Myocardial uptake of cocaine and effects of cocaine on myocardial substrate utilization and perfusion in hypertensive rats

Energy Technology Data Exchange (ETDEWEB)

Som, P.; Wang, G.J. [Brookhaven National Lab., Upton, NY (United States); Oster, Z.H. [State Univ. of New York, Stony Brook, NY (United States); Knapp, F.F. Jr. [Oak Ridge National Lab., TN (United States); Yonekura, Y. [Kyoto Univ. (Japan). Faculty of Medicine; Fujibayashi, Y. [Kyoto Univ. (Japan). Hospital; Yamamoto, K. [Fukui Univ. (Japan). Medical School; Kubota, K. [Tohoku Univ., Sendai (Japan)

1992-12-31

Cocaine abuse is a problem causing world-wide concern and the number of deaths following cocaine use is increasing. Cardiovascular complications following cocaine include severe tachyarrythmias, pulmonary edema, myocardial infarction, and acute renal failure, which are major problems confronting emergency facilities. While the studies of cocaine effects on the brain have been given the most attention, it is clear that the effects of cocaine on the cardiovascular system are of great importance, given the increasing number of reports on sudden death and myocardial infarctions in young adults related to cocaine use. The precise mechanisms of cardiotoxic actions of cocaine are unclear. We investigated the whole-body distribution of C-14-labeled cocaine to determine the cocaine-binding sites, including blocking experiments to determine the nature of regional binding sites, and differential response of the normal vs. diseased heart (hypertensive cardiomyopathy) in an animal model to mimic a potentially high risk population. We investigated the acute effects of cocaine on myocardial metabolism using two myocardial energy substrate analogs, fatty acid and glucose with comparison with regional perfusion.

Myocardial uptake of cocaine and effects of cocaine on myocardial substrate utilization and perfusion in hypertensive rats

Energy Technology Data Exchange (ETDEWEB)

Som, P.; Wang, G.J. (Brookhaven National Lab., Upton, NY (United States)); Oster, Z.H. (State Univ. of New York, Stony Brook, NY (United States)); Knapp, F.F. Jr. (Oak Ridge National Lab., TN (United States)); Yonekura, Y. (Kyoto Univ. (Japan). Faculty of Medicine); Fujibayashi, Y. (Kyoto Univ. (Japan). Hospital); Yamamoto, K. (Fukui Univ. (Japan). Medical School); Kubota, K. (Tohoku Univ., Sendai

1992-01-01

Cocaine abuse is a problem causing world-wide concern and the number of deaths following cocaine use is increasing. Cardiovascular complications following cocaine include severe tachyarrythmias, pulmonary edema, myocardial infarction, and acute renal failure, which are major problems confronting emergency facilities. While the studies of cocaine effects on the brain have been given the most attention, it is clear that the effects of cocaine on the cardiovascular system are of great importance, given the increasing number of reports on sudden death and myocardial infarctions in young adults related to cocaine use. The precise mechanisms of cardiotoxic actions of cocaine are unclear. We investigated the whole-body distribution of C-14-labeled cocaine to determine the cocaine-binding sites, including blocking experiments to determine the nature of regional binding sites, and differential response of the normal vs. diseased heart (hypertensive cardiomyopathy) in an animal model to mimic a potentially high risk population. We investigated the acute effects of cocaine on myocardial metabolism using two myocardial energy substrate analogs, fatty acid and glucose with comparison with regional perfusion.

Observations of super early left ventricular remodeling experimental myocardial infarction

International Nuclear Information System (INIS)

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

2004-01-01

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

Myocardial imaging with 99mTc-Tetrofosmin: Influence of post-stress acquisition time, regional radiotracer uptake, and wall motion abnormalities on the clinical result.

Science.gov (United States)

Giorgetti, Assuero; Kusch, Annette; Casagranda, Mirta; Tagliavia, Irene D'Aragona; Marzullo, Paolo

2010-04-01

We previously demonstrated that early (15', T1) post-stress myocardial imaging with Tetrofosmin could be more accurate than standard acquisitions (45', T2) in identifying coronary artery disease. To clarify this phenomenon, 120 subjects (age 61 +/- 10 years) with both T1 and T2 scans were divided into Group 1 (53/120 pts) with more ischemia at T1 vs T2 imaging (T1-T2SDS > or = 3); Group 2 (67/120 pts) with similar results (T1-T2SDS statistic and semiquantitative wall motion/thickening values were obtained. Analysis of T1 and T2 post-stress myocardial counts demonstrated a significant Tetrofosmin wash-out rate that was higher in Group 1 control nonischemic regions (15 +/- 8% vs 13.6 +/- 9.6%, P stress wall thickening (T1-T2) was lower in Group 1 ischemic regions (-4.5 +/- 9.15% vs -1.90 +/- 7.0%, P stress acquisition time because of ischemic-induced regional wall thickening abnormalities and the existence of a differential radiotracer myocardial wash-out.

Detection of viable myocardium in canine model with myocardial ischemia and ischemia-reperfusion by 125I-BMIPP: relation to regional blood flow

International Nuclear Information System (INIS)

Huang Gang; Zhao Huiyang; Shen Xuedong; Li Qing; Yuan Jimin; Zhu Cuiying

1999-01-01

Objective: The effects of BMIPP (β-methyl-iodophenyl pentadecanoic acid) on detecting viable myocardium and the relation between regional blood flow and the uptake of BMIPP were evaluated in canine model of myocardial ischemia and ischemia-reperfusion. Methods: 12 open-chest dogs under anesthesia were divided into two groups. Group I (ischemia group) had left circumflex coronary arterial occlusion for 2 h and group II (ischemia-reperfusion group) was occluded for 1 h and followed by 2 h reperfusion. Myocardial blood flow was measured with 99 Tc m -microspheres. 30 min after intravenous injection of 125 I-BMIPP and 99 Tc m -microspheres, the heart was excised rapidly and stained with Evans blue and NBT. Tissue samples (divided into approximately 1 g) of left ventricle were obtained, weighed and counted for 125 I and 99 Tc m . Regional blood flow and the uptake of BMIPP were expressed as percentages of average values in non-ischemic myocardium (two to three tissue samples) from the normal myocardium. Results: In ischemic myocardium (NBT positive samples), the uptake of BMIPP was relatively higher compared with regional blood flow [(67 +- 23)% vs (42 +- 19)%, P 0.05]. In ischemia-reperfusion group, regional blood flow was increased in ischemic and necrotic tissues, but the uptake of BMIPP was not enhanced with the increasing blood flow. Conclusions: BMIPP uptake seems to provide metabolic information independent of regional blood flow. The mismatching between regional blood flow and BMIPP uptake may indicate myocardial viability in the regions of hypoperfusion and the uptake of BMIPP in ischemic myocardium was related to existence of cellular metabolism

Detecting Regional Myocardial Abnormalities in Patients With Wolff-Parkinson-White Syndrome With the Use of ECG-Gated Cardiac MDCT.

Science.gov (United States)

Lee, Hye-Jeong; Uhm, Jae-Sun; Joung, Boyoung; Hong, Yoo Jin; Hur, Jin; Choi, Byoung Wook; Kim, Young Jin

2016-04-01

Myocardial dyskinesia caused by the accessory pathway and related reversible heart failure have been well documented in echocardiographic studies of pediatric patients with Wolff-Parkinson-White (WPW) syndrome. However, the long-term effects of dyskinesia on the myocardium of adult patients have not been studied in depth. The goal of the present study was to evaluate regional myocardial abnormalities on cardiac CT examinations of adult patients with WPW syndrome. Of 74 patients with WPW syndrome who underwent cardiac CT from January 2006 through December 2013, 58 patients (mean [± SD] age, 52.2 ± 12.7 years), 36 (62.1%) of whom were men, were included in the study after the presence of combined cardiac disease was excluded. Two observers blindly evaluated myocardial thickness and attenuation on cardiac CT scans. On the basis of CT findings, patients were classified as having either normal or abnormal findings. We compared the two groups for other clinical findings, including observations from ECG, echocardiography, and electrophysiologic study. Of the 58 patients studied, 16 patients (27.6%) were found to have myocardial abnormalities (i.e., abnormal wall thinning with or without low attenuation). All abnormal findings corresponded with the location of the accessory pathway. Patients with abnormal findings had statistically significantly decreased left ventricular function, compared with patients with normal findings (p syndrome. These abnormal findings might reflect the long-term effects of dyskinesia, suggesting irreversible myocardial injury that ultimately causes left ventricular dysfunction.

Myocardial perfusion in silent myocardial ischemia

International Nuclear Information System (INIS)

Narita, Michihiro; Kurihara, Tadashi; Murano, Kenichi; Usami, Masahisa

1989-01-01

To investigate myocardial perfusion in silent myocardial ischemia, we performed exercise stress myocardial tomography with thallium-201 (Tl) in 85 patients with coronary artery disease (CAD). Exercise stress myocardial tomography was obtained both immediately after exercise and three hours later. Patients were classified into two groups according to the presence (Symptomatic Group, n=36) or absence (Silent Group, n=49) of chest pain during exercise stress. Clinical features (age, gender and history of myocardial infarction) and arteriographically determined severity of CAD were the same in both groups. The extent of myocardial ischemia (% Ischemia) estimated by exercise stress myocardial tomography was the same in each group (30±10 % in Silent Group, 28±12 % in Symptomatic Group, NS). The severity of exercise-induced myocardial ischemia was expressed as a minimal value of myocardial Tl washout rate (minimal WOR) of each patient. Although exercise heart rate was identical in both groups, minimal WOR in Silent Group was significantly higher than that of Symptomatic Group (4±10% vs -16±14%, p<0.001). The study in patients who exhibited both silent and symptomatic ischemia showed the same results. These findings suggest that the severity of ischemia is a fundamental factor in determining the presence or absence of pain during exercise induced ischemia. (author)

Exercise and rest Tl-201 myocardial SPECT, and low dose dobutamine echocardiography to assess myocardial viability in patients with myocardial infarction

International Nuclear Information System (INIS)

Toyama, Takuji; Ishida, Yoshio; Shimonagata, Tsuyoshi; Kawano, Shigeo; Beppu, Shintaro; Nishimura, Tsunehiko.

1994-01-01

To evaluate viability of infarcted myocardium, findings of Tl-201 myocardial SPECT were compared with those of low-dose dobutamine (DOB) echocardiography. The subjects were 19 patients with myocardial infarction (23 infarcted zones), consisting of 16 men and 3 women. Findings on myocardial SPECT were classified as evidence of myocardial viability (14 zones, Group A) and no evidence of myocardial viability (9 zones, Group B). For both groups, wall motion and regional % uptake (%UP) were obtained. DOB echocardiography revealed an improvement in 5 of 8 akinesis zones in Group A. In addition, one other zone was found improved by follow-up examination. Six hypokinesis zones were all found improved on DOB echocardiography. Out of a total of 14 akinesis or hypokinesis zones, 11 (79%) showed improvement on DOB echocardiography in Group A. In Group B, all akinesis zones remained unchanged on DOB echocardiography, although one zone was improved by follow-up examination. In 11 zones in which wall motion was improved on DOB echocardiography, %UT was increased by an average of 58% on 4 hr-delayed images and 70% on resting images. The corresponding figures for 12 zones which did not improve on DOB echocardiography were 49% and 50% on the average, respectively. In conclusion, low-dose DOB echocardiography appeared to reflect viability of severely infarcted myocardium, although it had a slightly lower sensitivity than convensional Tl-201 myocardial SPECT in its ability to detect. (N.K.)

Rationale and radiopharmaceuticals for myocardial imaging

International Nuclear Information System (INIS)

Poe, N.D.

1976-01-01

Static radionuclide imaging procedures are now available for evaluating regional myocardial perfusion and for detecting acute myocardial infarction. Thallium-201, a radiopharmaceutical which possesses many of the characteristics of potassium analogs, at present is receiving the greatest attention as a regional blood flow indicator. Ischemic lesions appear as areas of decreased tracer uptake. Unfortunately, this agent is expensive, is in limited supply and has a photopeak which is low for optimum imaging. Positive infarct images can be obtained with various technetium-99m chelates. Pyrophosphate appears to be the best of the technetium compounds studied to date although the mechanism of uptake of the chelates has not yet been fully elucidated. Therefore, quantitative measurements of infarct size are not justified. As perfusion imaging and infarct imaging provide useful, complementary data, a dual tracer approach to evaluating patients with suspected coronary artery disease and/or myocardial infarction is probably justifiable

The expression of myocardial injury in cold induced myocardial imaging and echocardiography of systematic scleroderma

International Nuclear Information System (INIS)

Liang Jiugen; Zhu Xiaojun; Jiang Ningyi; Chen Shaoxiong

1999-01-01

The study was performed with cold-induced 99m Tc(MIBI) myocardial imaging (MI) in 23 patients with systematic scleroderma. The left ventricular function and wall motion were also observed by dimensional echocardiography (UCG). 14 patients had myocardial perfusion abnormalities visualized by MI, including 5 cases with fixed defects of 9 segments, 3 cases with reversible defects of 6 segments and 6 cases with both fixed and reversible one of 14 segments. The positive rate in myocardial imaging had no significant differences between patients with and without Raynaud's phenomenon (0.5>P>0.25). Compared with baseline, the ejection fraction, stroke volume, cardiac output were significantly decreased during cold-induced in patients with abnormal myocardial scintigraphy (P<0.05), and had significant difference compared with normal group (P<0.05). 4 cases with cold-induced reversible perfusion defects had anatomically correlated regional ventricular hypokinesia in UCG

Diffusion tensor imaging tensor shape analysis for assessment of regional white matter differences.

Science.gov (United States)

Middleton, Dana M; Li, Jonathan Y; Lee, Hui J; Chen, Steven; Dickson, Patricia I; Ellinwood, N Matthew; White, Leonard E; Provenzale, James M

2017-08-01

Purpose The purpose of this study was to investigate a novel tensor shape plot analysis technique of diffusion tensor imaging data as a means to assess microstructural differences in brain tissue. We hypothesized that this technique could distinguish white matter regions with different microstructural compositions. Methods Three normal canines were euthanized at seven weeks old. Their brains were imaged using identical diffusion tensor imaging protocols on a 7T small-animal magnetic resonance imaging system. We examined two white matter regions, the internal capsule and the centrum semiovale, each subdivided into an anterior and posterior region. We placed 100 regions of interest in each of the four brain regions. Eigenvalues for each region of interest triangulated onto tensor shape plots as the weighted average of three shape metrics at the plot's vertices: CS, CL, and CP. Results The distribution of data on the plots for the internal capsule differed markedly from the centrum semiovale data, thus confirming our hypothesis. Furthermore, data for the internal capsule were distributed in a relatively tight cluster, possibly reflecting the compact and parallel nature of its fibers, while data for the centrum semiovale were more widely distributed, consistent with the less compact and often crossing pattern of its fibers. This indicates that the tensor shape plot technique can depict data in similar regions as being alike. Conclusion Tensor shape plots successfully depicted differences in tissue microstructure and reflected the microstructure of individual brain regions. This proof of principle study suggests that if our findings are reproduced in larger samples, including abnormal white matter states, the technique may be useful in assessment of white matter diseases.

Myocardial turnover rates of I-123 heptadecanoic acid (HDA)

International Nuclear Information System (INIS)

Dudczak, R.; Schmoliner, R.; Kletter, K.; Derfler, D.K.; Frischauf, H.; Angelberger, P.; Losert, U.

1982-01-01

Myocardial scintigraphy was performed with I-123 labeled HDA in patients with coronary artery disease (CAD, n=37), cardiomyopathy (COCM, n=7) and controls (n=10). These results were compared with coronary angiography, Tl 201 scintigraphy and radionuclide angiography. Results from animal experiments (intracoronary application in calfes) and patient studies supported the assumption that myocardial scintigraphy with I-123 HDA reveals information about myocardial fatty acid utilisation. Summarizing all clinical results using I-123 HDA showed that from the myocardial accumulation pattern of the labeled fatty acid, as well as from Tl 201 perfusion scintigraphy, the value of the regional elimination rate (t/2) could not be predicted. In patients with COCM the mean t/2 was prolonged, but overlapped with controls. In ischemic regions ''shortened'', normal and prolonged elimination rates were found. These findings were related to the observed wall motion and the calculated regional ejection fraction (r=0.73, p<0.001). This data indicate, that I-123 HDA add a further aspect in nuclear cardiology; the results obtained bear a relation to the functional state of the diseased heart

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

International Nuclear Information System (INIS)

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

1986-01-01

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

The Hg region: Superdeformation and other shapes

International Nuclear Information System (INIS)

Janssens, R.V.F.; Carpenter, M.P.; Fernandez, P.B.; Moore, E.F.; Ahmad, I.; Khoo, T.L.; Wolfs, F.L.H.; Drigert, M.W.; Ye, D.; Beard, K.B.; Reviol, W.; Bearden, I.; Benet, P.; Daly, P.J.; Grabowski, Z.W.

1990-01-01

We shall first summarize the present experimental situation concerning 192 Hg, the nucleus regarded as the analog of 152 Dy 8 for this SD region in that shell gaps are calculated 5 to occur at large deformation for Z=80 and N=112. Proton and neutron excitations out of te 192 Hg core will then be reviewed with particular emphasis on 191 Hg and 193 Tl. The implications of the results for pairing at large deformations and the need to consider other degrees of freedom (such as octupole correlations) will be addressed. The presentation will conclude with a brief discussion on other shapes seen in this region, with a particular emphasis on 191 Hg

Regional interaction between myocardial sympathetic denervation, contractile dysfunction, and fibrosis in heart failure with preserved ejection fraction: {sup 11}C-hydroxyephedrine PET study

Energy Technology Data Exchange (ETDEWEB)

Aikawa, Tadao; Naya, Masanao; Obara, Masahiko [Hokkaido University, Department of Cardiovascular Medicine, Faculty of Medicine and Graduate School of Medicine, Sapporo (Japan); Oyama-Manabe, Noriko [Hokkaido University Hospital, Department of Diagnostic and Interventional Radiology, Sapporo (Japan); Manabe, Osamu [Hokkaido University, Department of Nuclear Medicine, Faculty of Medicine and Graduate School of Medicine, Sapporo (Japan); Magota, Keiichi [Hokkaido University Hospital, Division of Medical Imaging and Technology, Sapporo (Japan); Ito, Yoichi M. [Hokkaido University, Department of Biostatistics, Faculty of Medicine and Graduate School of Medicine, Sapporo (Japan); Katoh, Chietsugu [Hokkaido University, Department of Biomedical Science and Engineering, Faculty of Health Sciences, Sapporo (Japan); Tamaki, Nagara [Kyoto Prefectural University of Medicine, Department of Radiology, Kyoto (Japan)

2017-10-15

This investigation aimed to identify significant predictors of regional sympathetic denervation quantified by {sup 11}C-hydroxyephedrine (HED) positron emission tomography (PET) in patients with heart failure with preserved left ventricular ejection fraction (HFpEF). Included in the study were 34 patients (age 63 ± 15 years, 23 men) with HFpEF (left ventricular ejection fraction ≥40%) and 11 age-matched volunteers without heart failure. Cardiac magnetic resonance imaging was performed to measure left ventricular size and function, and the extent of myocardial late gadolinium enhancement (LGE). {sup 11}C-HED PET was performed to quantify myocardial sympathetic innervation that was expressed as a {sup 11}C-HED retention index (RI, %/min). To identify predictors of regional {sup 11}C-HED RI in HFpEF patients, we propose a multivariate mixed-effects model for repeated measures over segments with an unstructured covariance matrix. Global {sup 11}C-HED RI was significantly lower and more heterogeneous in HFpEF patients than in volunteers (P < 0.01 for all). Regional {sup 11}C-HED RI was correlated positively with systolic wall thickening (r = 0.42, P < 0.001) and negatively with the extent of LGE (r = -0.43, P < 0.001). Segments in HFpEF patients with a large extent of LGE had the lowest regional {sup 11}C-HED RI among all segments (P < 0.001 in post hoc tests). Multivariate analysis demonstrated that systolic wall thickening and the extent of LGE were significant predictors of regional {sup 11}C-HED RI in HFpEF patients (both P ≤ 0.001). Regional sympathetic denervation was associated with contractile dysfunction and fibrotic burden in HFpEF patients, suggesting that regional sympathetic denervation may provide an integrated measure of myocardial damage in HFpEF. (orig.)

Summation and Cancellation Effects on QRS and ST-Segment Changes Induced by Simultaneous Regional Myocardial Ischemia.

Science.gov (United States)

Vives-Borrás, Miquel; Jorge, Esther; Amorós-Figueras, Gerard; Millán, Xavier; Arzamendi, Dabit; Cinca, Juan

2018-01-01

Simultaneous ischemia in two myocardial regions is a potentially lethal clinical condition often unrecognized whose corresponding electrocardiographic (ECG) patterns have not yet been characterized. Thus, this study aimed to determine the QRS complex and ST-segment changes induced by concurrent ischemia in different myocardial regions elicited by combined double occlusion of the three main coronary arteries. For this purpose, 12 swine were randomized to combination of 5-min single and double coronary artery occlusion: Group 1: left Circumflex (LCX) and right (RCA) coronary arteries ( n = 4); Group 2: left anterior descending artery (LAD) and LCX ( n = 4) and; Group 3: LAD and RCA ( n = 4). QRS duration and ST-segment displacement were measured in 15-lead ECG. As compared with single occlusion, double LCX+RCA blockade induced significant QRS widening of about 40 ms in nearly all ECG leads and magnification of the ST-segment depression in leads V1-V3 (maximal 228% in lead V3, p ST-segment elevation in precordial leads (maximal attenuation of 60% in lead V3 in LAD+LCX and 86% in lead V5 in LAD+RCA, p ST-segment elevation in leads V7-V9 was a specific sign of single LCX occlusion. In conclusion, concurrent infero-lateral ischemia was associated with a marked summation effect of the ECG changes previously elicited by each single ischemic region. By contrast, a cancellation effect on ST-segment changes with no QRS widening was observed when the left anterior descending artery was involved.

Thallium-201 myocardial imaging

International Nuclear Information System (INIS)

Wackers, F.J.Th.

1980-01-01

Three views are routinely obtained for 201 Tl scintigraphy: 0 0 anterior, 45 0 left-anterior-oblique, both views with the patient supine and a left-lateral view, with the patient lying on his right side. Following intravenous injection of 201 Tl, the scintiscans of a normal subject only demonstrate the left ventricle. In patients with normal myocardial perfusion, the left ventricle appears horseshoe or ovoid in shape. The central area of decreased activity represents the left ventricular cavity and is normal. The accumulation of 201 Tl in the normal left ventricle is usually homogeneous. However, some areas with apparent diminished uptake may occur in the normal subject. These variations of the normal image are discussed. The right ventricle, because of its smaller myocardial mass and relatively less 201 Tl accumulation per gram of tissue, is usually on a resting study not, or only faintly, visualized. However, following exercise, the right ventricle is clearly visualized. (Auth.)

3D cardiac wall thickening assessment for acute myocardial infarction

Science.gov (United States)

Khalid, A.; Chan, B. T.; Lim, E.; Liew, Y. M.

2017-06-01

Acute myocardial infarction (AMI) is the most severe form of coronary artery disease leading to localized myocardial injury and therefore irregularities in the cardiac wall contractility. Studies have found very limited differences in global indices (such as ejection fraction, myocardial mass and volume) between healthy subjects and AMI patients, and therefore suggested regional assessment. Regional index, specifically cardiac wall thickness (WT) and thickening is closely related to cardiac function and could reveal regional abnormality due to AMI. In this study, we developed a 3D wall thickening assessment method to identify regional wall contractility dysfunction due to localized myocardial injury from infarction. Wall thickness and thickening were assessed from 3D personalized cardiac models reconstructed from cine MRI images by fitting inscribed sphere between endocardial and epicardial wall. The thickening analysis was performed in 5 patients and 3 healthy subjects and the results were compared against the gold standard 2D late-gadolinium-enhanced (LGE) images for infarct localization. The notable finding of this study is the highly accurate estimation and visual representation of the infarct size and location in 3D. This study provides clinicians with an intuitive way to visually and qualitatively assess regional cardiac wall dysfunction due to infarction in AMI patients.

The thallium-201 myocardial scintigraphy, its possibilities and limitations

International Nuclear Information System (INIS)

Adam, W.; Meindl, S.; Schmitz, A.; Utech, C.; Boettcher, D.

1983-01-01

The Thallium-201 Myocardial Scintigraphy, its Possibilities and limitations: The Thallium-201 myocardial scintigraphy is a simple non-invasive procedure to detect hypo- and non-perfused myocardial regions. In the he last years it was demonstrated to be a helpful method in the diagnostic strategy for the cardiologist. It can not replace the coronary angiogram, but in many cases it appears to be useful in selecting patients for coronary angiography. (orig.) [de

Overestimation of myocardial infarct size on two-dimensional echocardiograms due to remodelling of the infarct zone.

Science.gov (United States)

Johnston, B J; Blinston, G E; Jugdutt, B I

1994-01-01

To assess the effect of early regional diastolic shape distortion or bulging of infarct zones due to infarct expansion on estimates of regional left ventricular dysfunction and infarct size by two-dimensional echocardiographic imaging. Quantitative two-dimensional echocardiograms from patients with a first Q wave myocardial infarction and creatine kinase infarct size data, and normal subjects, were subjected to detailed analysis of regional left ventricular dysfunction and shape distortion in short-axis images by established methods. Regional left ventricular asynergy (akinesis and dyskinesis) and shape distortion indices (eg, peak [Pk]/radius [ri]) were measured on endocardial diastolic outlines of short-axis images in 43 postinfarction patients (28 anterior and 15 inferior, 5.9 h after onset) and 11 normal subjects (controls). In the infarction group, endocardial surface area of asynergy was calculated by three-dimensional reconstruction of the images and infarct size from serial creatine kinase blood levels. Diastolic bulging of asynergic zones was found in all infarction patients. The regional shape distortion indices characterizing the area between the 'actual' bulging asynergic segment and the derived 'ideal' circular segment (excluding the bulge) on indexed sections were greater in infarct than control groups (Pk/ri 0.31 versus 0, P 0.001). Importantly, the degree of distortion correlated with overestimation of asynergy (r = 0.89, P < 0.001), and the relation between infarct size and total 'ideal' asynergy showed a leftward shift from that with 'actual' asynergy. Early regional diastolic bulging of the infarct zone results in overestimation of regional ventricular dysfunction, especially in patients with anterior infarction. This effect should be considered when assessing effects of therapy on infarct size, remodelling and dysfunction using tomographical imaging.

Normal values of regional left ventricular myocardial thickness, mass and distribution-assessed by 320-detector computed tomography angiography in the Copenhagen General Population Study

DEFF Research Database (Denmark)

Hindsø, Louise; Fuchs, Andreas; Kühl, Jørgen Tobias

2017-01-01

regional normal reference values of the left ventricle. The aim of this study was to derive reference values of regional LV myocardial thickness (LVMT) and mass (LVMM) from a healthy study group of the general population using cardiac computed tomography angiography (CCTA). We wanted to introduce LV...... myocardial distribution (LVMD) as a measure of regional variation of the LVMT. Moreover, we wanted to determine whether these parameters varied between men and women. We studied 568 (181 men; 32%) adults, free of cardiovascular disease and risk factors, who underwent 320-detector CCTA. Mean age was 55 (range...... 40-84) years. Regional LVMT and LVMM were measured, according to the American Heart Association's 17 segment model, using semi-automatic software. Mean LVMT were 6.6 mm for men and 5.4 mm for women (p normal LV was thickest in the basal septum (segment 3; men = 8.3 mm; women = 7.2 mm...

Improved exercise myocardial perfusion during lidoflazine therapy

International Nuclear Information System (INIS)

Shapiro, W.; Narahara, K.A.; Park, J.

1983-01-01

Lidoflazine is a synthetic drug with calcium-channel blocking effects. In a study of 6 patients with severe classic angina pectoris, single-blind administration of lidoflazine was associated with improved myocardial perfusion during exercise as determined by thallium-201 stress scintigraphy. These studies demonstrate that lidoflazine therapy is associated with relief of angina, an increased physical work capacity, and improved regional myocardial perfusion during exercise

Myocardial Bridge

Science.gov (United States)

... Center > Myocardial Bridge Menu Topics Topics FAQs Myocardial Bridge En español Your heart is made of muscle, ... surface of the heart. What is a myocardial bridge? A myocardial bridge is a band of heart ...

Positron imaging in the evaluation of ischemia and myocardial infarction

International Nuclear Information System (INIS)

Goldstein, R.A.

1985-01-01

Positron emission tomography (PET) is a unique imaging approach since it allows quantification of regional myocardial radioactivity by virtue of its decay characteristics. Studies of regional myocardial metabolism are possible since there are positron emitting isotopes of carbon, oxygen and nitrogen that can be used to synthesize labeled fatty acids, amino acids or carbohydrate. Recent studies from the author's group have focused on Rb-82, a diffusible cation with a short half-life that is obtained from a generator and thus, has the potential for routine clinical use without a cyclotron. In this chapter, the basic principles of positron imaging and their application to imaging of acute myocardial infarction are discussed

The cardiomyopathy in Friedreich's ataxia: isotopic ventriculography and myocardial imaging with thallium-201

International Nuclear Information System (INIS)

Therriault, L.; Lamoureux, G.; Cote, M.; Plourde, G.; Lemieux, B.

1984-01-01

Myocardial scanning after the intravenous administration of Thallium 201 was used to evaluate regional myocardial perfusion in 14 patients with Friedreich's ataxia. Isotopic ventriculography was also used to assess left ventricular contractility. Myocardial images in patients with Friedreich's ataxia were found to be precociously abnormal irrespective of the degree of neurological impairment or of the severity of myocardial hypertrophy

[Association between collateral circulation and myocardial viability evaluated by cardiac magnetic resonance imaging in patients with coronary artery chronic total occlusion].

Science.gov (United States)

Li, J N; Zhang, L J; He, Y; Chen, Y L; Huang, R C; Lyu, S Z; Song, X T

2017-07-24

Objective: Late gadolinium enhancement(LGE) cardiac magnetic resonance imaging(CMR) was used to evaluate the myocardial viability of chronic total occlusion(CTO) in patients with coronary heart disease and to observe the relationship between collateral circulation and myocardium viability in these patients. Methods: This retrospective study included 40 patients with CTO diagnosed by invasive coronary angiography (CAG) from September 2015 to June 2016 in our department, all patients performed CMR examination within one week after CAG.The collateral circulation of CTO was graded with Rentrop classification as follows: poor or no collateral circulation group, moderate collateral circulation group and good collateral circulation group.According to CMR images, the delayed enhancement transmural extent of myocardial segments were scored, the ventricular wall motion of the myocardial segment were graded, and the wall motion score index (WMSI) was calculated.Spearman correlation analysis was used to analyze the relationship between the delayed enhancement transmural extent of myocardial segments and WMSI. Results: In the no or poor collateral group of 6 myocardial regions, 1 myocardial region had viable myocardium and 3 myocardial regions had no viable myocardium; in the moderate collateral group of 16 myocardial regions, 11 myocardial regions had viable myocardium and 5 myocardial regions had no viable myocardium; in the good collateral group of 24 myocardial regions, 21 myocardial regions had viable myocardium and 3 myocardial regions had no viable myocardium, there was significant difference between the groups ( P =0.002). The WMSI of poor or no collateral circulation group, moderate collateral circulation group and good collateral circulation group were 1.54±0.50, 1.21±0.34 and 1.26±0.40, respectively, there was no significant difference between the groups ( P =0.063). Spearman correlation analysis showed that the extent of delayed enhancement transmural extent of

Attenuation correction of myocardial SPECT by scatter-photopeak window method in normal subjects

International Nuclear Information System (INIS)

Okuda, Koichi; Nakajima, Kenichi; Matsuo, Shinro; Kinuya, Seigo; Motomura, Nobutoku; Kubota, Masahiro; Yamaki, Noriyasu; Maeda, Hisato

2009-01-01

Segmentation with scatter and photopeak window data using attenuation correction (SSPAC) method can provide a patient-specific non-uniform attenuation coefficient map only by using photopeak and scatter images without X-ray computed tomography (CT). The purpose of this study is to evaluate the performance of attenuation correction (AC) by the SSPAC method on normal myocardial perfusion database. A total of 32 sets of exercise-rest myocardial images with Tc-99m-sestamibi were acquired in both photopeak (140 keV±10%) and scatter (7% of lower side of the photopeak window) energy windows. Myocardial perfusion databases by the SSPAC method and non-AC (NC) were created from 15 female and 17 male subjects with low likelihood of cardiac disease using quantitative perfusion SPECT software. Segmental myocardial counts of a 17-segment model from these databases were compared on the basis of paired t test. AC average myocardial perfusion count was significantly higher than that in NC in the septal and inferior regions (P<0.02). On the contrary, AC average count was significantly lower in the anterolateral and apical regions (P<0.01). Coefficient variation of the AC count in the mid, apical and apex regions was lower than that of NC. The SSPAC method can improve average myocardial perfusion uptake in the septal and inferior regions and provide uniform distribution of myocardial perfusion. The SSPAC method could be a practical method of attenuation correction without X-ray CT. (author)

Neuroanatomic correlates of stroke-related myocardial injury.

Science.gov (United States)

Ay, H; Koroshetz, W J; Benner, T; Vangel, M G; Melinosky, C; Arsava, E M; Ayata, C; Zhu, M; Schwamm, L H; Sorensen, A G

2006-05-09

Myocardial injury can occur after ischemic stroke in the absence of primary cardiac causes. The neuroanatomic basis of stroke-related myocardial injury is not well understood. To identify regions of brain infarction associated with myocardial injury using a method free of the bias of an a priori hypothesis as to any specific location. Of 738 consecutive patients with acute ischemic stroke, the authors identified 50 patients in whom serum cardiac troponin T (cTnT) elevation occurred in the absence of any apparent cause within 3 days of symptom onset. Fifty randomly selected, age- and sex-matched patients with ischemic stroke without cTnT elevation served as controls. Diffusion-weighted images with outlines of infarction were co-registered to a template, averaged, and then subtracted to find voxels that differed between the two groups. Voxel-wise p values were determined using a nonparametric permutation test to identify specific regions of infarction that were associated with cTnT elevation. The study groups were well balanced with respect to stroke risk factors, history of coronary artery disease, infarction volume, and frequency of right and left middle cerebral artery territory involvement. Brain regions that were a priori associated with cTnT elevation included the right posterior, superior, and medial insula and the right inferior parietal lobule. Among patients with right middle cerebral artery infarction, the insular cluster was involved in 88% of patients with and 33% without cTnT elevation (odds ratio: 15.00; 95% CI: 2.65 to 84.79). Infarctions in specific brain regions including the right insula are associated with elevated serum cardiac troponin T level indicative of myocardial injury.

Variability of insulin-stimulated myocardial glucose uptake in healthy elderly subjects

DEFF Research Database (Denmark)

Kofoed, Klaus F; Hove, Jens D; Freiberg, Jacob

2002-01-01

The aim of this study was to assess regional and global variability of insulin-stimulated myocardial glucose uptake in healthy elderly subjects and to evaluate potentially responsible factors. Twenty men with a mean age of 64 years, no history of cardiovascular disease, and normal blood pressure...... rest and hyperaemic blood flow during dipyridamole infusion were measured with nitrogen-13 ammonia and positron emission tomography in 16 left ventricular myocardial segments. Intra-individual and inter-individual variability of insulin-stimulated myocardial glucose uptake [relative dispersion...... = (standard deviation/mean)] was 13% and 29% respectively. Although inter-individual variability of glucose uptake and blood flow at rest was of the same magnitude, no correlation was found between these measures. Regional and global insulin-stimulated myocardial glucose uptake correlated linearly with whole...

Myocardial ischemia and angina pectoris. The clinical problem in patients

Energy Technology Data Exchange (ETDEWEB)

Selwyn, A.P.; Fox, K.M.; Jonathan, A.; Lavender, P.; Watson, I.

1981-02-01

Ambulatory monitoring of ST segment changes was performed in 60 patients presenting with angina, positive ECG stress tests and coronary artery disease, 85% of ischemic ECG events were asymptomatic, 37% occurred with no increase in heart rate and 15% of episodes either lasted 20 minutes or more or fluctuated in severity. A controlled pilot study in ten patients showed depression. Radionuclide studies in 50 patients with angina and coronary artery disease have shown that stress (i.e., atrial pacing) produced different patterns of disturbed regional myocardial perfusion related to the patient's exercise capacity and eventually leading to a decrease in regional myocardial perfusion during the ischemic episode. ST segment depression appeared only after the decrease in regional myocardial perfusion. These findings combined with past research suggest that patients with angina and coronary artery disease can suffer frequent asymptomatic disturbances of the regional myocardial perfusion. The frequency of these episodes and the time course for the recovery of the metabolic consequences mean that segments of ventricular myocardium may be constantly abnormal. The relative importance of changes in coronary tone and malfunction of platelets in the diseased coronary tree needs to be examined in clinical research. Pilot studies of antiplatelet agents have shown a significant beneficial effect on episodes of ischemia occurring at night and those occurring without any increase in heart rate. The techniques and observations in these patients with coronary artery disease all suggest that acute transient regional myocardial ischemia is caused by a variety of mechanisms. Further research using objective methods is required to discover the causes of ischemia and to rationalize treatment.

PHARMACOEPIDEMIOLOGIC ANALYSIS OF ST-ELEVATION MYOCARDIAL INFARCTION REPERFUSION THERAPY AT SARATOV REGION HOSPITALS OF DIFFERENT TYPES

Directory of Open Access Journals (Sweden)

O. V. Reshetko

2016-01-01

Full Text Available Aim. To evaluate the real practice of thrombolytic therapy of patients with ST-elevation myocardial infarction (STEMI at cardiological departments of Saratov and Saratov region hospitals.Material and methods. Retrospective pharmacoepidemiologic study was carried out. Case histories of STEMI patients discharged from cardiologic departments of several central district hospitals (CDH of Saratov region, cardiologic department of one of Saratov general municipal hospitals (MH and urgent cardiology department of Saratov clinical hospital (CH in 2006 were analyzed.Results. In CH all patients received thrombolytic therapy given they did not have contraindications and were admitted to the hospital timely. Few patients received thrombolytic therapy in MH and CDH in 2006.Conclusion. Correlation between hospital type and quality of STEMI management has been revealed.

Usefulness of 123I-BMIPP myocardial imaging in patients with stable effort angina and unstable angina

International Nuclear Information System (INIS)

Inoue, Seiji; Kobayashi, Hideki; Oka, Toshiaki; Kawaguchi, Masao; Momose, Mitsuru; Kasanuki, Hiroshi; Kusakabe, Kiyoko; Hosoda, Saichi

1995-01-01

We evaluated the clinical significance of myocardial imaging using 123 I-15-(p-iodophenyl)-3-methyl pentadecanoic acid (BMIPP) scintigraphy in patients with stable effort angina pectoris (SAP) and unstable angina pectoris (UAP). Thirty-three patients with SAP were studied using rest BMIPP and stress 201 TlCl (Tl) myocardial scintigraphy, and 13 patients with worsening effort type of UAP were also examined using both rest BMIPP and Tl scintigraphy. We compared those BMIPP findings with myocardial perfusion images obtained with Tl and the regional wall motion determined by left ventriculography. In 45% of 282 segments of myocardial ischemia of SAP, the degree of myocardial uptake of BMIPP was concordant with that of stress Tl and the defect score of Tl was higher than that of BMIPP. On the other hand, in 32% of 62 segments of ischemia of UAP, the degree of myocardial BMIPP and Tl uptake was concordant and BMIPP defect score was higher than Tl score. In SAP, the decrease in regional wall motion agreed better with the decrease in myocardial uptake of BMIPP than that of Tl. These results suggest that myocardial ischemic regions decreased BMIPP uptake show the disturbance of fatty acid metabolism and lead to abnormal wall motions. Such ischemic regions may be clinically severe state in patients with angina pectoris. (author)

Chronic myocardial infarction detection and characterization during coronary artery calcium scoring acquisitions.

LENUS (Irish Health Repository)

Rodríguez-Granillo, Gastón A

2012-01-05

Hypoenhanced regions on multidetector CT (MDCT) coronary angiography correlate with myocardial hyperperfusion. In addition to a limited capillary density, chronic myocardial infarction (MI) commonly contains a considerable amount of adipose tissue.

Myocardial perfusion SPECT imaging in patients with myocardial bridging

International Nuclear Information System (INIS)

Fang Wei; Qiu Hong; Yang Weixian; Wang Feng; He Zuoxiang

2008-01-01

Objective: Stress myocardial perfusion SPECT imaging was used to assess myocardial ischemia in patients with myocardial bridging. Methods: Ninety-six patients with myocardial bridging of the left anterior descending artery documented by coronary angiography were included in this study. All under- went exercise or pharmacological stress myocardial perfusion SPECT assessing myocardial ischemia. None had prior myocardial infarction. One year follow-up by telephone interview was performed in all patients. Results The mean stenotic severity of systolic phase on angiography was (65 ± 19)%. In the SPECT study, 20 of 96 (20.8%) patients showed abnormal perfusion. This percentage was significantly higher than that of stress electrocardiogram (ECG). The higher positive rate of SPECT perfusion images was showed in the group of patients with severe systolic narrowing (≥75%) than that with mild-to-moderate systolic narrowing (50% vs 6.3%, P<0.001). The prevalence of abnormal image was significantly higher in ELDERLY PEOPLE; patients with STT change on rest ECG than in those with normal rest ECG (54.2% vs 9.7%, P<0.001). During follow-up, one patient with abnormal SPECT perfusion image sustained angina and accepted percutaneous coronary intervention, and no cardiac event occurred in patients with normal images. Conclusions: Stress myocardial perfusion SPECT imaging can be used effectively for assessing myocardial ischemia and has potential prognostic value for patients with myocardial bridging. (authors)

Correlation between Left Ventricular Global and Regional Longitudinal Systolic Strain and Impaired Microcirculation in Patients with Acute Myocardial Infarction

DEFF Research Database (Denmark)

Løgstrup, Brian B; Høfsten, Dan Eik; Christophersen, Thomas Brøcher

2012-01-01

investigated if LRS and GLS imaging is superior to conventional measures of left ventricle (LV) function. Methods: In a consecutive population of first time AMI patients, who underwent successful revascularization, we performed comprehensive TTE. GLS and LRS were obtained from the three standard apical views...... elevation myocardial infarction. The GLS was -15.2 [-19.3;-10.1]% in the total population of 183 patients. Total wall motion score index (WMSI) in the population was 1.19 [1;1.5]. Eighty-five patients suffered from culprit lesion in left anterior descending artery (LAD). The CFR in these patients was 1......Objectives: We investigated the correlation between left ventricular global and regional longitudinal systolic strain (GLS and LRS) and coronary flow reserve (CFR) assessed by transthoracic echocardiography (TTE) in patients with a recent acute myocardial infarction (AMI). Furthermore, we...

delta-Opioid-induced pharmacologic myocardial hibernation during cardiopulmonary resuscitation.

Science.gov (United States)

Fang, Xiangshao; Tang, Wanchun; Sun, Shijie; Weil, Max Harry

2006-12-01

Cardiac arrest and cardiopulmonary resuscitation is an event of global myocardial ischemia and reperfusion, which is associated with severe postresuscitation myocardial dysfunction and fatal outcome. Evidence has demonstrated that mammalian hibernation is triggered by cyclic variation of a delta-opiate-like compound in endogenous serum, during which the myocardial metabolism is dramatically reduced and the myocardium tolerates the stress of ischemia and reperfusion without overt ischemic and reperfusion injury. Previous investigations also proved that the delta-opioid agonist elicited the cardioprotection in a model of regional ischemic intact heart or myocyte. Accordingly, we were prompted to search for an alternative intervention of pharmacologically induced myocardial hibernation that would result in rapid reductions of myocardial metabolism and therefore minimize the myocardial ischemic and reperfusion injury during cardiac arrest and cardiopulmonary resuscitation. Prospective, controlled laboratory study. University-affiliated research laboratory. In the series of studies performed in the established rat and pig model of cardiac arrest and cardiopulmonary resuscitation, the delta-opioid receptor agonist, pentazocine, was administered during ventricular fibrillation. : The myocardial metabolism reflected by the concentration of lactate, or myocardial tissue PCO2 and PO2, is dramatically reduced during cardiac arrest and cardiopulmonary resuscitation. These are associated with less severe postresuscitation myocardial dysfunction and longer duration of postresuscitation survival. delta-Opioid-induced pharmacologic myocardial hibernation is an option to minimize the myocardial ischemia and reperfusion injury during cardiac arrest and cardiopulmonary resuscitation.

Histochemical and immunohistochemical analyses of the myocardial scar fallowing acute myocardial infarction

Directory of Open Access Journals (Sweden)

Tatić Vujadin

2012-01-01

Full Text Available Background/Aim. The heart has traditionally been considered as a static organ without capacity of regeneration after trauma. Currently, the more and more often asked question is whether the heart has any intrinsic capacities to regenerate myocytes after myocardial infarction. The aim of this study was to present the existence of the preserved muscle fibers in the myocardial scar following myocardial infarction as well as the presence of numerous cells of various size and form that differently reacted to the used immunohistochemical antibodies. Methods. Histological, histochemical and immunohistochemical analyses of myocardial sections taken from 177 patients who had died of acute myocardial infarction and had the myocardial scar following myocardial infarction, were carried out. More sections taken both from the site of acute infarction and scar were examined by the following methods: hematoxylin-eosin (HE, periodic acid schiff (PAS, PAS-diastasis, Masson trichrom, Malory, van Gieson, vimentin, desmin, myosin, myoglobin, alpha actin, smoth muscle actin (SMA, p53, leukocyte common antigen (LCA, proliferating cell nuclear antigen (PCNA, Ki-67, actin HHF35, CD34, CD31, CD45, CD45Ro, CD8, CD20. Results. In all sections taken from the scar region, larger or smaller islets of the preserved muscle fibers with the signs of hypertrophy were found. In the scar, a large number of cells of various size and form: spindle, oval, elongated with abundant cytoplasm, small with one nucleus and cells with scanty cytoplasm, were found. The present cells differently reacted to histochemical and immunohistochemical methods. Large oval cells showed negative reaction to lymphocytic and leukocytic markers, and positive to alpha actin, actin HHF35, Ki-67, myosin, myoglobin and desmin. Elongated cells were also positive to those markers. Small mononuclear cells showed positive reaction to lymphocytic markers. Endothelial and smooth muscle cells in the blood vessel walls

Evaluation of left ventricular myocardial function in patients with coronary artery disease and myocardial dysfunction before and after coronary artery bypass grafting by cine magnetic resonance imaging

International Nuclear Information System (INIS)

Juergens, K.U.; Renger, B.; Reimer, P.; Tombach, B.; Heindel, W.; Wichter, T.; Bruns, H.J.; Vahlhaus, C.; Janssen, F.W.; Breithardt, G.

2001-01-01

Purpose: To evaluate left ventricular (LV) myocardial function in ten patients with coronary artery disease (CAD) preoperatively and 6 months after coronary bypass grafting (CABG) by cardiac MRI. Material and methods: Ten patients (mean 65.2±5.9 years) with angiographically proven CAD and an indication for elective CABG underwent prospective evaluation of global LV function and regional wall motion by Cine-MRI at rest using a multiphase FLASH-2D sequence following regions of interest (ROI)-defined diagnostics of regional myocardial wall motion by means of levocardiography. Within the ROIs a total of 613 LV myocardial segments were analyzed preceding and following surgical revascularization. Results were compared with the data of 10 healthy volunteers. Results: Preoperatively, patients showed reduced stroke volume and ejection fraction compared with volunteers (p [de

Quantitative evaluation of myocardial perfusion and heart function using a non-invasive double isotope technique

Energy Technology Data Exchange (ETDEWEB)

Knapp, W H; Doll, J; Georgi, P [Deutsches Krebsforschungszentrum, Heidelberg (Germany, F.R.). Inst. fuer Nuklearmedizin; Tillmanns, H [Heidelberg Univ. (Germany, F.R.). Innere Medizin 3

1976-11-01

This paper describes a non-invasive double nuclide technique for the simultaneous measurement of minimal cardiac transit times (MTT) and regional 'myocardial appearance times' (MAT) using gamma camera and computer. MAT is defined as the time lag between the appearance of an indicator with myocardial affinity in the aortic root and its extraction in the myocardial cells. The extraction can be identified as an increase of the ratio between the count rates of the two nuclides e.g. /sup 201/Tl-chloride and sup(113m)In DTPA. The clinical evaluation of this method allows the following conclusions: 1) MAT, determined over several circumscript myocardial regions permits the qualitative diagnosis of a coronary artery disease with high confidence. 2) Indices of nutritive myocardial blood flow (INF), derived by MAT using several representative areas of myocardium, show a definite correlation to the degree of coronary artery disease. In addition to the localization of infarction and the determination of infarct size, the technique described promises a quantitative evaluation of the regional myocardial perfusion. Simultaneously measured MTT help to assess segmental cardiac performance.

Tomoscintigraphic assessment of myocardial metabolic heterogenity

International Nuclear Information System (INIS)

Roesler, H.; Hess, T.; Weiss, M.; Noelpp, U.; Mueller, G.; Hoeflin, F.; Kinser, J.

1983-01-01

I-123-omega-heptadecanoic acid (HDA) was evaluated for myocardial scanning in 59 healthy volunteers and 133 patients, using a 7-pinhole collimator. Early (uptake) and late (retention) images were compared visually. Regional HDA elimination was also followed semiquantitatively based on the calculation of a retention-over-uptake ratio, R(phi), derived from the maximal counts/pixel in 60 midventricular slice sectors. The healthy heart concentrated HDA homogeneously in all segments with no difference between early and late images. The minimal R(phi), taken as representative of that myocardium with the best function, was unchanged after maximal ergometer stress and with dipyramidole-induced hyperperfusion. A circumscribed decreased HDA uptake is the clear-cut criterion for an abnormal finding. HDA tomography of the myocardium had an 86% sensitivity for myocardial infarcts (MIs) up to 4 wk old, and 83% for myocardial scars (MSs). Comparing early and late tomograms, we find a cool-warm sequence more often with acute and subacute MIs. A cool-cool or a cold-cold sequence dominated with MSs. HDA tomoscintigraphy cannot replace TI-201 for the evaluation of regional coronary reserve in coronary heart disease

Simultaneous cardiac output and regional myocardial perfusion determination with PET and nitrogen 13 ammonia

DEFF Research Database (Denmark)

Hove, Jens D; Kofoed, Klaus F; Wu, Hsiao M

2003-01-01

The purpose of this study was to evaluate the possibility of measuring cardiac output during positron emission tomography (PET) examination of myocardial perfusion with nitrogen 13 ammonia.......The purpose of this study was to evaluate the possibility of measuring cardiac output during positron emission tomography (PET) examination of myocardial perfusion with nitrogen 13 ammonia....

Automated region selection for analysis of dynamic cardiac SPECT data

Science.gov (United States)

Di Bella, E. V. R.; Gullberg, G. T.; Barclay, A. B.; Eisner, R. L.

1997-06-01

Dynamic cardiac SPECT using Tc-99m labeled teboroxime can provide kinetic parameters (washin, washout) indicative of myocardial blood flow. A time-consuming and subjective step of the data analysis is drawing regions of interest to delineate blood pool and myocardial tissue regions. The time-activity curves of the regions are then used to estimate local kinetic parameters. In this work, the appropriate regions are found automatically, in a manner similar to that used for calculating maximum count circumferential profiles in conventional static cardiac studies. The drawbacks to applying standard static circumferential profile methods are the high noise level and high liver uptake common in dynamic teboroxime studies. Searching along each ray for maxima to locate the myocardium does not typically provide useful information. Here we propose an iterative scheme in which constraints are imposed on the radii searched along each ray. The constraints are based on the shape of the time-activity curves of the circumferential profile members and on an assumption that the short axis slices are approximately circular. The constraints eliminate outliers and help to reduce the effects of noise and liver activity. Kinetic parameter estimates from the automatically generated regions were comparable to estimates from manually selected regions in dynamic canine teboroxime studies.

Iodophenylpentadecanoic acid-myocardial blood flow relationship during maximal exercise with coronary occlusion

Energy Technology Data Exchange (ETDEWEB)

Caldwell, J.H.; Martin, G.V.; Link, J.M.; Krohn, K.A.; Bassingthwaighte, J.B. (Seattle VA Medical Center, WA (USA))

1990-01-01

Imaging {sup 123}I-labeled iodophenylpentadecanoic acid (IPPA) uptake and clearance from the myocardium following exercise has been advocated as a means of detecting myocardial ischemia because fatty acid deposition is enhanced and clearance prolonged in regions of low flow. However, normal regional myocardial blood flows are markedly heterogeneous, and it is not known how this heterogeneity affects regional metabolism or substrate uptake and thus image interpretation. In five instrumented dogs running at near maximal workload on a treadmill, {sup 131}I-labeled IPPA and 15-micron 46Sc microspheres were injected into the left atrium after 30 sec of circumflex coronary artery occlusion. Microsphere and IPPA activity were determined in 250 mapped pieces of myocardium of approximately 400 mg. Myocardial blood flows (from microspheres) ranged from 0.05 to 7.6 ml/min/g. Deposition of IPPA was proportional to regional flows (r = 0.83) with an average retention of 25%. The mean endocardial-epicardial ratio for IPPA (0.90 {plus minus} 0.43) was similar to that for microspheres (0.94 {plus minus} 0.47; p = 0.08). Thus, initial IPPA deposition during treadmill exercise increases in proportion to regional myocardial blood flow over a range of flows from very low to five times normal.

Iodophenylpentadecanoic acid-myocardial blood flow relationship during maximal exercise with coronary occlusion

International Nuclear Information System (INIS)

Caldwell, J.H.; Martin, G.V.; Link, J.M.; Krohn, K.A.; Bassingthwaighte, J.B.

1990-01-01

Imaging 123 I-labeled iodophenylpentadecanoic acid (IPPA) uptake and clearance from the myocardium following exercise has been advocated as a means of detecting myocardial ischemia because fatty acid deposition is enhanced and clearance prolonged in regions of low flow. However, normal regional myocardial blood flows are markedly heterogeneous, and it is not known how this heterogeneity affects regional metabolism or substrate uptake and thus image interpretation. In five instrumented dogs running at near maximal workload on a treadmill, 131 I-labeled IPPA and 15-micron 46Sc microspheres were injected into the left atrium after 30 sec of circumflex coronary artery occlusion. Microsphere and IPPA activity were determined in 250 mapped pieces of myocardium of approximately 400 mg. Myocardial blood flows (from microspheres) ranged from 0.05 to 7.6 ml/min/g. Deposition of IPPA was proportional to regional flows (r = 0.83) with an average retention of 25%. The mean endocardial-epicardial ratio for IPPA (0.90 ± 0.43) was similar to that for microspheres (0.94 ± 0.47; p = 0.08). Thus, initial IPPA deposition during treadmill exercise increases in proportion to regional myocardial blood flow over a range of flows from very low to five times normal

Iodophenylpentadecanoic acid-myocardial blood flow relationship during maximal exercise with coronary occlusion.

Science.gov (United States)

Caldwell, J H; Martin, G V; Link, J M; Krohn, K A; Bassingthwaighte, J B

1990-01-01

Imaging 123I-labeled iodophenylpentadecanoic acid (IPPA) uptake and clearance from the myocardium following exercise has been advocated as a means of detecting myocardial ischemia because fatty acid deposition is enhanced and clearance prolonged in regions of low flow. However, normal regional myocardial blood flows are markedly heterogeneous, and it is not known how this heterogeneity affects regional metabolism or substrate uptake and thus image interpretation. In five instrumented dogs running at near maximal workload on a treadmill, 131I-labeled IPPA and 15-micron 46Sc microspheres were injected into the left atrium after 30 sec of circumflex coronary artery occlusion. Microsphere and IPPA activity were determined in 250 mapped pieces of myocardium of approximately 400 mg. Myocardial blood flows (from microspheres) ranged from 0.05 to 7.6 ml/min/g. Deposition of IPPA was proportional to regional flows (r = 0.83) with an average retention of 25%. The mean endocardial-epicardial ratio for IPPA (0.90 +/- 0.43) was similar to that for microspheres (0.94 +/- 0.47; p = 0.08). Thus, initial IPPA deposition during treadmill exercise increases in proportion to regional myocardial blood flow over a range of flows from very low to five times normal.

Recovery of BMIPP uptake and regional wall motion in insulin resistant patients following angioplasty for acute myocardial infarction

Energy Technology Data Exchange (ETDEWEB)

Fujino, Takayuki; Ishii, Yoshinao; Hirasawa, Kunihiko; Tateda, Kunihiko [Asahikawa City Hospital, Hokkaido (Japan); Takeuchi, Toshiharu; Kikuchi, Kenjiro; Hasebe, Naoyuki [Asahikawa Medical Coll., Hokkaido (Japan)

2003-09-01

The effect of insulin resistance (IR) on the fatty acid metabolism of myocardium, and therefore on the recovery of left ventricular (LV) wall motion, has not been established in patients with acute myocardial infarction (AMI). A total of consecutive 58 non-diabetic AMI patients who had successfully undergone emergency coronary angioplasty were analyzed retrospectively. They were categorized into 2 groups, normal glucose tolerance (NGT) and impaired glucose tolerance (IGT), based on a 75-g oral glucose tolerance test (OGTT). The parameters of OGTT, myocardial scintigraphy (n=58) (thallium-201 (Tl) and iodine-123-{beta}-methyl-iodophenylpentadecanoic acid (BMIPP)) and left ventriculography (n=24) were compared in the 2 groups after reperfusion (acute phase) and 3-4 weeks after the AMI (chronic phase). The IR, estimated by the serum concentration of insulin at 120 min (IRI 120') of the OGTT and by the HOMA (the homeostasis model assessment) index, was higher in the IGT group than in NGT group. An inverse correlation was found between the recovery of regional LV wall motion in the ischemic lesion and the IRI 120' and HOMA index. Although the recovery of BMIPP uptake from the acute to the chronic phase was higher in the IGT group, it was only correlated with the degree of IRI 120', not with the HOMA. IR accompanied by IGT can negatively influence the recovery of regional LV wall motion. (author)

Recovery of BMIPP uptake and regional wall motion in insulin resistant patients following angioplasty for acute myocardial infarction

International Nuclear Information System (INIS)

Fujino, Takayuki; Ishii, Yoshinao; Hirasawa, Kunihiko; Tateda, Kunihiko; Takeuchi, Toshiharu; Kikuchi, Kenjiro; Hasebe, Naoyuki

2003-01-01

The effect of insulin resistance (IR) on the fatty acid metabolism of myocardium, and therefore on the recovery of left ventricular (LV) wall motion, has not been established in patients with acute myocardial infarction (AMI). A total of consecutive 58 non-diabetic AMI patients who had successfully undergone emergency coronary angioplasty were analyzed retrospectively. They were categorized into 2 groups, normal glucose tolerance (NGT) and impaired glucose tolerance (IGT), based on a 75-g oral glucose tolerance test (OGTT). The parameters of OGTT, myocardial scintigraphy (n=58) (thallium-201 (Tl) and iodine-123-β-methyl-iodophenylpentadecanoic acid (BMIPP)) and left ventriculography (n=24) were compared in the 2 groups after reperfusion (acute phase) and 3-4 weeks after the AMI (chronic phase). The IR, estimated by the serum concentration of insulin at 120 min (IRI 120') of the OGTT and by the HOMA (the homeostasis model assessment) index, was higher in the IGT group than in NGT group. An inverse correlation was found between the recovery of regional LV wall motion in the ischemic lesion and the IRI 120' and HOMA index. Although the recovery of BMIPP uptake from the acute to the chronic phase was higher in the IGT group, it was only correlated with the degree of IRI 120', not with the HOMA. IR accompanied by IGT can negatively influence the recovery of regional LV wall motion. (author)

Recovery of BMIPP uptake and regional wall motion in insulin resistant patients following angioplasty for acute myocardial infarction.

Science.gov (United States)

Fujino, Takayuki; Ishii, Yoshinao; Takeuchi, Toshiharu; Hirasawa, Kunihiko; Tateda, Kunihiko; Kikuchi, Kenjiro; Hasebe, Naoyuki

2003-09-01

The effect of insulin resistance (IR) on the fatty acid metabolism of myocardium, and therefore on the recovery of left ventricular (LV) wall motion, has not been established in patients with acute myocardial infarction (AMI). A total of consecutive 58 non-diabetic AMI patients who had successfully undergone emergency coronary angioplasty were analyzed retrospectively. They were categorized into 2 groups, normal glucose tolerance (NGT) and impaired glucose tolerance (IGT), based on a 75-g oral glucose tolerance test (OGTT). The parameters of OGTT, myocardial scintigraphy (n=58) (thallium-201 (Tl) and iodine-123-beta-methyl-iodophenylpentadecanoic acid (BMIPP)) and left ventriculography (n=24) were compared in the 2 groups after reperfusion (acute phase) and 3-4 weeks after the AMI (chronic phase). The insulin resistance (IR), estimated by the serum concentration of insulin at 120 min (IRI 120') of the OGTT and by the HOMA (the homeostasis model assessment) index, was higher in the IGT group than in NGT group. An inverse correlation was found between the recovery of regional LV wall motion in the ischemic lesion and the IRI 120' and HOMA index. Although the recovery of BMIPP uptake from the acute to the chronic phase was higher in the IGT group, it was only correlated with the degree of IRI 120', not with the HOMA. IR accompanied by IGT can negatively influence the recovery of regional LV wall motion.

Dynamic modeling and dynamical analysis of pump-turbines in S-shaped regions during runaway operation

International Nuclear Information System (INIS)

Zhang, Hao; Chen, Diyi; Wu, Changzhi; Wang, Xiangyu; Lee, Jae-Myung; Jung, Kwang-Hyo

2017-01-01

Highlights: • Novel dynamic model of a pump-turbine in S-shaped regions is proposed. • A stability criterion of runaway point is given. • Global dynamic characteristics of the pump-turbine are investigated. • Effects of the slopes of the characteristic curve on the stability are studied. - Abstract: There is a region of pump-turbine operation, often called the S-shaped region, in which one unit rotational speed corresponds to three unit flows or torques. In this paper, the dynamic model of the pump-turbine in S-shaped regions is established by introducing the nonlinear piecewise function of relative parameters. Then, the global bifurcation diagrams of the pump-turbine are presented to analyze its dynamic characteristics in the S-shaped regions. Meanwhile, a stability criterion of runaway point is given based on the established theoretical model. The numerical experiments are conducted on the model and the results are in good agreement with the theoretical analysis. Furthermore, the effects of the characteristic curve slopes on the stability of the pump-turbine are studied by an innovative use of the three-dimensional bifurcation diagrams. Finally, the factors influencing the runaway stability of pump-turbines are also discussed, based on the dynamic analysis.

Electro-mechanical characteristics of myocardial infarction border zones and ventricular arrhythmic risk: novel insights from grid-tagged cardiac magnetic resonance imaging

International Nuclear Information System (INIS)

Wong, Dennis T.L.; Weightman, Michael J.; Baumert, Mathias; Tayeb, Hussam; Richardson, James D.; Puri, Rishi; Bertaso, Angela G.; Roberts-Thomson, Kurt C.; Sanders, Prashanthan; Worthley, Matthew I.; Worthley, Stephen G.

2012-01-01

To investigate whether grid-tag myocardial strain evaluation can characterise 'border-zone' peri-infarct region and identify patients at risk of ventricular arrhythmia as the peri-infarct myocardial zone may represent an important contributor to ventricular arrhythmia following ST-segment elevation myocardial infarction (STEMI). Forty-five patients with STEMI underwent cardiac magnetic resonance (CMR) imaging on days 3 and 90 following primary percutaneous coronary intervention (PCI). Circumferential peak circumferential systolic strain (CS) and strain rate (CSR) were calculated from grid-tagged images. Myocardial segments were classified into 'infarct', 'border-zone', 'adjacent' and 'remote' regions by late-gadolinium enhancement distribution. The relationship between CS and CSR and these distinct myocardial regions was assessed. Ambulatory Holter monitoring was performed 14 days post myocardial infarction (MI) to estimate ventricular arrhythmia risk via evaluation of heart-rate variability (HRV). We analysed 1,222 myocardial segments. Remote and adjacent regions had near-normal parameters of CS and CSR. Border-zone regions had intermediate CS (-9.0 ± 4.6 vs -5.9 ± 7.4, P < 0.001) and CSR (-86.4 ± 33.3 vs -73.5 ± 51.4, P < 0.001) severity compared with infarct regions. Patients with 'border-zone' peri-infarct regions had reduced very-low-frequency power on HRV analysis, which is a surrogate for ventricular arrhythmia risk (P = 0.03). Grid-tagged CMR-derived myocardial strain accurately characterises the mechanical characteristics of 'border-zone' peri-infarct region. Presence of 'border-zone' peri-infarct region correlated with a surrogate marker of heightened arrhythmia risk following STEMI. (orig.)

Evaluation of nonradioactive, colored microspheres for measurement of regional myocardial blood flow in dogs

International Nuclear Information System (INIS)

Hale, S.L.; Alker, K.J.; Kloner, R.A.

1988-01-01

Measurement of regional myocardial blood flow (RMBF) is crucial in experimental studies of myocardial ischemia and reperfusion in dogs. The standard measurement technique uses radioactive microspheres; however, not all institutions are able to dispose of radioactive waste and therefore cannot make use of this method. We tested a new, nonradioactive microsphere, labeled with colors instead of nuclides. Simultaneous blood flow measurements with two nuclide-labeled and two colored microspheres were performed after coronary occlusion in dogs. Both techniques show a within-method correlation of r greater than 0.98. Duplicate variability for paired RMBF values in 80 samples was 8.7 +/- 0.1% when computed with radioactive microspheres and 13.2 +/- 1.8% when computed with colored microspheres. There was a good correlation in the measurement of RMBF between the radioactive- and colored-microsphere methods (r = 0.98). The best-fitting linear regression line was expressed by the formula: Colored-microsphere RMBF = 1.11 (radioactive-microsphere RMBF)-0.02. When measured by colored microspheres, RMBF was approximately 8% higher than when computed with radioactive microspheres for blood flow values of 0-2 ml/min/g. When blood flow was increased pharmacologically to levels of 2-7.5 ml/min/g, colored microspheres yielded blood flow values 39% higher than the values computed by radioactive microspheres. We conclude that the nonradioactive, colored-microsphere method correlates with the radioactive technique, but at high flows, it yields values greater than those obtained with radioactive microspheres

Tumor necrosis factor-alpha increases myocardial microvascular transport in vivo

DEFF Research Database (Denmark)

Hansen, P R; Svendsen, Jesper Hastrup; Høyer, S

1994-01-01

Tumor necrosis factor-alpha (TNF-alpha) is a primary mediator in the pathogenesis of tissue injury, and high circulating levels of TNF-alpha are found in a variety of pathological conditions. In open-chest anesthetized dogs, the effects of intracoronary recombinant human TNF-alpha (rTNF-alpha; 100...... in cardiac output and was associated with the appearance of areas with myocardial necrosis in the regional left ventricular wall. The myocardial plasma flow rate and maximum plasma flow rate in response to a 30-s coronary occlusion were not influenced by rTNF-alpha, although a decrease in the myocardial...... ng/kg for 60 min) on myocardial microvascular transport of a small hydrophilic indicator was examined by the single-injection, residue-detection method. Intracoronary infusion of rTNF-alpha increased myocardial microvascular transport after 120 min. This increase was preceded by a sustained decline...

Imaging of cocaine-induced global and regional myocardial ischemia

International Nuclear Information System (INIS)

Oster, Z.H.; Som, P.; Wang, G.J.; Weber, D.A.

1991-01-01

Severe and often fatal cardiac complications have been reported in cocaine users with narrowed coronary arteries caused by atherosclerosis as well as in young adults with normal coronaries. The authors have found that in normal dogs cocaine induces severe temporary hypoperfusion of the left ventricle as indicated by a significantly lower 201Tl concentration compared to the baseline state. The most significant decrease in uptake occurred 5 min after injection and was more pronounced in the septal and apical segments. Following intravenous administration of cocaine, instead of gradual disappearance of 201Tl from the left ventricle, there was continuous increase in 201Tl concentration in the left ventricle. These imaging experiments indicate that the deleterious effects of cocaine on the heart are probably due to spasm of the coronaries and decreased myocardial perfusion. Since spasm of the large subpericardial vessels does not seem to explain the magnitude of the increased coronary resistance and decreased coronary flow after cocaine as described in the literature, it is suggested that microvascular spasm of smaller vessels plays a major role in the temporary decrease in perfusion. The data may also suggest that severe temporary myocardial ischemia is probably the initiating factor for the cardiac complications induced by cocaine

Myocardial perfusion and left ventricular function during exercise evaluated by 201Tl myocardial scintigraphy and 99mTc radionuclide ventriculography in patients treated with PTCA

International Nuclear Information System (INIS)

Honda, Toshio; Jo, Tadafumi; Doiuchi, Junji

1992-01-01

To evaluate the effects of percutaneous transluminal coronary angioplasty (PTCA), we investigated myocardial ischemia and left ventricular function during exercise before and after successful PTCA in 30 patients. We used extent and severity scores of 201 thallium ( 201 Tl) exercise myocardial scintigraphy to assess myocardial ischemia and determined global and regional left ventricular ejection fraction (EF and REF) of 99m Tc-RBC exercise radionuclide ventriculography to assess left ventricular function. The extent and severity scores of stress images were significantly less after PTCA than before PTCA. The scores of the redistribution images were unchanged before and after PTCA. Global EF during exercise was significantly higher after PTCA than before PTCA. There was no difference in resting global EF between before and after PTCA. Myocardial ischemia induced by exercise was semi-quantitatively analyzed as transient perfusion defect with severity score. Severity score was significantly less after PTCA than before PTCA. ΔEF, which was obtained by subtraction of resting global EF from exercise one, was significantly higher after PTCA than before PTCA. However, the degree of improvement in myocardial ischemia and left ventricular function varied from patient to patient. In 17 patients with one-vessel left anterior descending artery disease, ΔREF, which was determined by subtracting resting regional EF from exercise one, was significantly higher in septal and apical segments after PTCA than before PTCA. Myocardial ischemia and left ventricular function under exercise were alleviated by PTCA. However, the degree of improvement varied from patient to patient and it might have been affected by various factors including coronary dissection, edema, thrombus, restenosis, spasm, side branch stenosis or occlusion, distal thrombus, and myocardial hibernation. (author)

Selection of reference genes in different myocardial regions of an in vivo ischemia/reperfusion rat model for normalization of antioxidant gene expression

Directory of Open Access Journals (Sweden)

Vesentini Nicoletta

2012-02-01

Full Text Available Abstract Background Changes in cardiac gene expression due to myocardial injury are usually assessed in whole heart tissue. However, as the heart is a heterogeneous system, spatial and temporal heterogeneity is expected in gene expression. Results In an ischemia/reperfusion (I/R rat model we evaluated gene expression of mitochondrial and cytoplasmatic superoxide dismutase (MnSod, Cu-ZnSod and thioredoxin reductase (trxr1 upon short (4 h and long (72 h reperfusion times in the right ventricle (RV, and in the ischemic/reperfused (IRR and the remote region (RR of the left ventricle. Gene expression was assessed by Real-time reverse-transcription quantitative PCR (RT-qPCR. In order to select most stable reference genes suitable for normalization purposes, in each myocardial region we tested nine putative reference genes by geNorm analysis. The genes investigated were: Actin beta (actb, Glyceraldehyde-3-P-dehydrogenase (gapdh, Ribosomal protein L13A (rpl13a, Tyrosine 3-monooxygenase (ywhaz, Beta-glucuronidase (gusb, Hypoxanthine guanine Phosphoribosyltransferase 1 (hprt, TATA binding box protein (tbp, Hydroxymethylbilane synthase (hmbs, Polyadenylate-binding protein 1 (papbn1. According to our findings, most stable reference genes in the RV and RR were hmbs/hprt and hmbs/tbp/hprt respectively. In the IRR, six reference genes were recommended for normalization purposes; however, in view of experimental feasibility limitations, target gene expression could be normalized against the three most stable reference genes (ywhaz/pabp/hmbs without loss of sensitivity. In all cases MnSod and Cu-ZnSod expression decreased upon long reperfusion, the former in all myocardial regions and the latter in IRR alone. trxr1 expression did not vary. Conclusions This study provides a validation of reference genes in the RV and in the anterior and posterior wall of the LV of cardiac ischemia/reperfusion model and shows that gene expression should be assessed separately in

Shape tracking with occlusions via coarse-to-fine region-based sobolev descent

KAUST Repository

Yang, Yanchao

2015-05-01

We present a method to track the shape of an object from video. The method uses a joint shape and appearance model of the object, which is propagated to match shape and radiance in subsequent frames, determining object shape. Self-occlusions and dis-occlusions of the object from camera and object motion pose difficulties to joint shape and appearance models in tracking. They are unable to adapt to new shape and appearance information, leading to inaccurate shape detection. In this work, we model self-occlusions and dis-occlusions in a joint shape and appearance tracking framework. Self-occlusions and the warp to propagate the model are coupled, thus we formulate a joint optimization problem. We derive a coarse-to-fine optimization method, advantageous in tracking, that initially perturbs the model by coarse perturbations before transitioning to finer-scale perturbations seamlessly. This coarse-to-fine behavior is automatically induced by gradient descent on a novel infinite-dimensional Riemannian manifold that we introduce. The manifold consists of planar parameterized regions, and the metric that we introduce is a novel Sobolev metric. Experiments on video exhibiting occlusions/dis-occlusions, complex radiance and background show that occlusion/dis-occlusion modeling leads to superior shape accuracy. © 2014 IEEE.

Proton chemical shift imaging after myocardial infarction

International Nuclear Information System (INIS)

Bouchard, A.; Doyle, M.; Pohost, G.M.

1989-01-01

The present study was undertaken to test whether chemical shift imaging could detect spatially the lipids known to accumulate in myocardium after an ischemic insult. Seven dogs underwent a 24-hour coronary artery occlusion. Hearts were removed and imaged ex vivo by the Dixon method (1.5 T), and myocardial samples were obtained for high-resolution H-1 spectroscopy. Lipid images revealed regions of increased signal intensity in the periphery f the myocardial infarction. The zones of high lipid signal corresponded to zones with elevated mobile lipids as detected by H-1 spectroscopy

Shape coexistence and mixing in N ∼ 20 region

International Nuclear Information System (INIS)

Utsuno, Yutaka; Otsuka, Takaharu; Mizusaki, Takahiro; Honma, Michio

2005-01-01

Spherical-deformed shape coexistence in the N ∼ 20 region is studied with the Monte Carlo shell model calculation. We focused upon the role of the configuration mixing in its description, and found that the deformed state is not correctly positioned until the mixing is treated in a proper way. It is also mentioned that the intruder component in 33 Al is accessible through the measurement of the magnetic moment

Myocardial perfusion scintigraphy with thallium-201 - principle and method

International Nuclear Information System (INIS)

Dressler, J.

1981-01-01

Since from the cardiological and cardio-surgical aspects non-invasive methods practicable in the diagnostics of regional myocardial blood perfusion are claiming priority, the myocardial perfusion scintigraphy with thallium 201 has gained more and more importance in the diagnostics of coronary heart diseases. Although radiothallium because of its nucleo-physical characteristics is not regarded as ideal radiopharmaceutical, it is at present, because of its potassium-analogue biokinetics the best radiopharmaceutical to represent the regional coronary perfusion distribution, the vitality and configuration of the heart muscle non-invasively. With careful clinical indication and under consideration of the physico-technical limitations, the informative value provided by the serial scintigraphy with thallium 201 is greater than that provided by the excercise ECG. Various possibilities for solving the problem of quantitative analysis of the myocardial scintigrams have been given. Up to the present day a standardised evaluation procedure corresponding to that of the visual scintigram interpretation has not yet found general acceptance. (orig.) [de

Myocardial viability in cases with persistent perfusion defects on the dipyridamole thallium-201 scintigram. A comparative study with autopsy findings

International Nuclear Information System (INIS)

Nakayama, Masafumi; Mashima, Saburo; Ohkawa, Shin-ichiro; Tanno, Munehiko; Yamada, Hideo.

1996-01-01

The aim of this study was to assess the incidence of myocardial infarction among persistent perfusion defects in dipyridamole-stress thallium scintigraphy by inspecting autopsied hearts and to evaluate whether the regional thallium activity of a scintigraphic defect can predict the presence of infarction. Autopsied hearts were compared with dipyridamole myocardial scintigrams undertaken during life in 27 patients (mean age 85±8 years). The time interval from stress testing until death was 428±351 days. Regional thallium uptake of delayed perfusion defect was calculated on the short axis images. The grade of regional myocardial fibrosis in autopsy specimens was also quantified to correlate with the corresponding regional thallium uptake. In 6 of 15 (40%) regions with persistent defects on the scintigram, myocardial infarction was not found at autopsy. Regional thallium-201 uptake of delayed defects < 50% diagnosed infarction with a sensitivity of 82% and a specificity of 80%. A linear correlation (r=-0.67) was observed between percent thallium-201 uptake and the degree of myocardial fibrosis. In conclusion, perfusion defects at 4-hour imaging in dipyridamole-stress testing may overestimate the presence of myocardial infarction and regional thallium-201 activity is helpful in distinguishing between defects with and without infarction. (author)

Functional tests for myocardial ischemia

International Nuclear Information System (INIS)

Levinson, J.R.; Guiney, T.E.; Boucher, C.A.

1991-01-01

Functional tests for myocardial ischemia are numerous. Most depend upon a combination of either exercise or pharmacologic intervention with analysis of the electrocardiogram, of regional perfusion with radionuclide imaging, or of regional wall motion with radionuclide imaging or echocardiography. While each test has unique features, especially at the research level, they are generally quite similar in clinical practice, so the clinician is advised to concentrate on one or two in which local expertise is high.22 references

Prospective assessment of regional myocardial perfusion before and after coronary revascularization surgery by quantitative thallium-201 scintigraphy

International Nuclear Information System (INIS)

Gibson, R.S.; Watson, D.D.; Taylor, G.J.; Crosby, I.K.; Wellons, H.L.; Holt, N.D.; Beller, G.A.

1983-01-01

Because thallium-201 uptake relates directly to the amount of viable myocardium and nutrient blood flow, the potential for exercise scintigraphy to predict response to coronary revascularization surgery was investigated in 47 consecutive patients. All patients underwent thallium-201 scintigraphy and coronary angiography at a mean (+/- standard deviation) of 4.3 +/- 3.1 weeks before and 7.5 +/- 1.6 weeks after surgery. Thallium uptake and washout were computer-quantified and each of six segments was defined as normal, showing total or partial redistribution or a persistent defect. Persistent defects were further classified according to the percent reduction in regional thallium activity; PD25-50 denoted a 25 to 50% constant reduction in relative thallium activity and PD greater than 50 denoted a greater than 50% reduction. Of 82 segments with total redistribution before surgery, 76 (93%) showed normal thallium uptake and washout postoperatively, versus only 16 (73%) of 22 with partial redistribution (probability [p] . 0.01). Preoperative ventriculography revealed that 95% of the segments with total redistribution had preserved wall motion, versus only 74% of those with partial redistribution (p . 0.01). Of 42 persistent defects thought to represent myocardial scar before surgery, 19 (45%) demonstrated normal perfusion postoperatively. Of the persistent defects that showed improved thallium perfusion postoperatively, 75% had normal or hypokinetic wall motion before surgery, versus only 14% of those without improvement (p less than 0.001). Whereas 57% of the persistent defects that showed a 25 to 50% decrease in myocardial activity demonstrated normal thallium uptake and washout postoperatively, only 21% of the persistent defects with a decrease in myocardial activity greater than 50% demonstrated improved perfusion after surgery (p . 0.02)

Left ventricular regional myocardial motion and twist function in repaired tetralogy of Fallot evaluated by magnetic resonance tissue phase mapping

International Nuclear Information System (INIS)

Chang, Meng-Chu; Peng, Hsu-Hsia; Wu, Ming-Ting; Weng, Ken-Pen; Su, Mao-Yuan; Menza, Marius; Huang, Hung-Chieh

2018-01-01

We aimed to characterise regional myocardial motion and twist function in the left ventricles (LV) in patients with repaired tetralogy of Fallot (rTOF) and preserved LV global function. We recruited 47 rTOF patients and 38 age-matched normal volunteers. Tissue phase mapping (TPM) was performed for evaluating the LV myocardial velocity in longitudinal, radial, and circumferential (Vz, Vr, and VOe) directions in basal, middle, and apical slices. The VOe peak-to-peak (PTP) during systolic phases, the rotation angle of each slice, and VOe inconsistency were computed for evaluating LV twist function and VOe dyssynchrony. As compared to the controls, the rTOF patients presented decreased RV ejection fraction (RVEF) (p = 0.002) and preserved global LV ejection fraction (LVEF). They also demonstrated decreased systolic and diastolic Vz in several LV segments and higher diastolic Vr in the septum (all p < 0.05). A lower VOe PTP, higher VOe inconsistency, and reduced peak net rotation angle (all p < 0.05) were observed. The aforementioned indices demonstrated an altered LV twist function in rTOF patients in an early disease stage. MR TPM could provide information about early abnormalities of LV regional motion and twist function in rTOF patients with preserved LV global function. (orig.)

Left ventricular regional myocardial motion and twist function in repaired tetralogy of Fallot evaluated by magnetic resonance tissue phase mapping

Energy Technology Data Exchange (ETDEWEB)

Chang, Meng-Chu; Peng, Hsu-Hsia [National Tsing Hua University, Department of Biomedical Engineering and Environmental Sciences, Hsinchu (China); Wu, Ming-Ting [Kaohsiung Veterans General Hospital, Department of Radiology, Kaohsiung (China); National Yang-Ming University, Faculty of Medicine, Taipei (China); Weng, Ken-Pen [National Yang-Ming University, Faculty of Medicine, Taipei (China); Kaohsiung Veterans General Hospital, Department of Pediatrics, Kaohsiung (China); Shu-Zen Junior College of Medicine and Management, Department of Physical Therapy, Kaohsiung (China); Su, Mao-Yuan [National Taiwan University Hospital, Department of Medical Imaging, Taipei (China); Menza, Marius [Medical Center University of Freiburg, Faculty of Medicine, University of Freiburg, Department of Radiology, Medical Physics, Freiburg (Germany); Huang, Hung-Chieh [Kaohsiung Veterans General Hospital, Department of Radiology, Kaohsiung (China)

2018-01-15

We aimed to characterise regional myocardial motion and twist function in the left ventricles (LV) in patients with repaired tetralogy of Fallot (rTOF) and preserved LV global function. We recruited 47 rTOF patients and 38 age-matched normal volunteers. Tissue phase mapping (TPM) was performed for evaluating the LV myocardial velocity in longitudinal, radial, and circumferential (Vz, Vr, and VOe) directions in basal, middle, and apical slices. The VOe peak-to-peak (PTP) during systolic phases, the rotation angle of each slice, and VOe inconsistency were computed for evaluating LV twist function and VOe dyssynchrony. As compared to the controls, the rTOF patients presented decreased RV ejection fraction (RVEF) (p = 0.002) and preserved global LV ejection fraction (LVEF). They also demonstrated decreased systolic and diastolic Vz in several LV segments and higher diastolic Vr in the septum (all p < 0.05). A lower VOe PTP, higher VOe inconsistency, and reduced peak net rotation angle (all p < 0.05) were observed. The aforementioned indices demonstrated an altered LV twist function in rTOF patients in an early disease stage. MR TPM could provide information about early abnormalities of LV regional motion and twist function in rTOF patients with preserved LV global function. (orig.)

The use of coronary vasodilators in myocardial imaging with 43K

International Nuclear Information System (INIS)

Markov, A.K.; Smith, R.O.; Oglethorpe, N.C.; Lehan, P.H.; Hellems, H.K.

1980-01-01

As an alternative procedure to the exercise stress test used in myocardial scanning, vasoactive drugs were employed to elicit deficits in blood flow to myocardial regions supplied by stenotic arteries. The data were collected from 35 dogs, some of which had partial stenosis on either major branch of the left coronary artery, and others which had Ameroid constrictor implants. The effects of lidoflazine, dipyridamole, and nitroglycerin on coronary hemodynamics and myocardial dispersion of 43 K in animals with partial stenosis were evaluated in ten acute experiments. In the pilot studies, four rapid serial rectilinear control scans from 43 K (750 μCi) were reported; dipyridamole, lidoflazine, or nitroglycerin were then administered intravenously. When the selected drug reached a peak vasodilatative effect, a second equal bolus of 43 K was given and four additional scans recorded. The control scans from dogs with partial stenosis or an Ameroid constrictor showed homogeneous distribution of the myocardial 43 K. When drugs were used, the region supplied by compromised circulation became apparent because of lower counts when compared to the normally perfused ones. Coronary vasodilators, as opposed to postexercise in myocardial imaging, have a lesser effect on cardiac dynamics, peripheral hemodynamics, and also double the 43 K uptake in normally perfused myocardium. (orig.) [de

THE SPEKL-TREKING PREDICTIVE VALUE OF THE ECHOCARDIOGRAPHY AT THE ACUTE MYOCARDIAL INFARCTION

Directory of Open Access Journals (Sweden)

N. A. Kosheleva

2016-01-01

Full Text Available Speckle-tracking echocardiography is a non-invasive method  for assessment of myocardial deformation, which is closely associated with its regional and global function. Although it is not yet introduced into clinical practice, deformation parameters are actively studied in different clinical conditions, particularly in acute myocardial infarction. Numerous studies show deformation  impairment may have important prognostic value at patients with a acute myocardial infarction.

Comparison of clinical tools for measurements of regional stress and rest myocardial blood flow assessed with 13N-ammonia PET/CT.

Science.gov (United States)

Slomka, Piotr J; Alexanderson, Erick; Jácome, Rodrigo; Jiménez, Moises; Romero, Edgar; Meave, Aloha; Le Meunier, Ludovic; Dalhbom, Magnus; Berman, Daniel S; Germano, Guido; Schelbert, Heinrich

2012-02-01

Several models for the quantitative analysis of myocardial blood flow (MBF) at stress and rest and myocardial flow reserve (MFR) with (13)N-ammonia myocardial perfusion PET have been implemented for clinical use. We aimed to compare quantitative results obtained from 3 software tools (QPET, syngo MBF, and PMOD), which perform PET MBF quantification with either a 2-compartment model (QPET and syngo MBF) or a 1-compartment model (PMOD). We considered 33 adenosine stress and rest (13)N-ammonia studies (22 men and 11 women). Average age was 54.5 ± 15 y, and average body mass index was 26 ± 4.2. Eighteen patients had a very low likelihood of disease, with no chest pain, normal relative perfusion results, and normal function. All data were obtained on a PET/CT scanner in list mode with CT attenuation maps. Sixteen dynamic frames were reconstructed (twelve 10-s, two 30-s, one 1-min, and one 6-min frames). Global and regional stress and rest MBF and MFR values were obtained with each tool. Left ventricular contours and input function region were obtained automatically in system QPET and syngo MBF and manually in PMOD. The flow values and MFR values were highly correlated among the 3 packages (R(2) ranging from 0.88 to 0.92 for global values and from 0.78 to 0.94 for regional values. Mean reference MFR values were similar for QPET, syngo MBF, and PMOD (3.39 ± 1.22, 3.41 ± 0.76, and 3.66 ± 1.19, respectively) by 1-way ANOVA (P = 0.74). The lowest MFR in very low likelihood patients in any given vascular territory was 2.25 for QPET, 2.13 for syngo MBF, and 2.23 for PMOD. Different implementations of 1- and 2-compartment models demonstrate an excellent correlation in MFR for each vascular territory, with similar mean MFR values.

Myocardial Bridging

Directory of Open Access Journals (Sweden)

Shi-Min Yuan

2016-02-01

Full Text Available Abstract Myocardial bridging is rare. Myocardial bridges are most commonly localized in the middle segment of the left anterior descending coronary artery. The anatomic features of the bridges vary significantly. Alterations of the endothelial morphology and the vasoactive agents impact on the progression of atherosclerosis of myocardial bridging. Patients may present with chest pain, myocardial infarction, arrhythmia and even sudden death. Patients who respond poorly to the medical treatment with β-blockers warrant a surgical intervention. Myotomy is a preferred surgical procedure for the symptomatic patients. Coronary stent deployment has been in limited use due to the unsatisfactory long-term results.

Myocardial perfusion in type 2 diabetes with left ventricular hypertrophy

DEFF Research Database (Denmark)

Hesse, Birger; Meyer, Christian; Nielsen, Flemming S

2004-01-01

The purpose of this study was to assess whether acute angiotensin-converting enzyme (ACE) inhibition would improve myocardial perfusion and perfusion reserve in a subpopulation of normotensive patients with diabetes and left ventricular hypertrophy (LVH), both independent risk factors of coronary...... disease. Using positron emission tomography (PET), we investigated the response of regional myocardial perfusion to acute ACE inhibition with i.v. infusion of perindoprilat (vs saline infusion as control, minimum interval 3 days) in 12 diabetic patients with LVH. Myocardial perfusion was quantified...... with controls, maximal perfusion was reduced in patients (1.8+/-0.6 vs 2.5+/-1.0 ml min(-1) g(-1); P2.7+/-1.0 vs 3.6+/-1.3; P=0.059). During perindoprilat infusion, myocardial perfusion reserve in patients increased to 3.9+/-0.9 ( P

Incidence, Frequency, and Clinical Characteristics of Type 3 Myocardial Infarction in Clinical Practice

DEFF Research Database (Denmark)

Jangaard, Nikolaj; Sarkisian, Laura; Saaby, Lotte

2017-01-01

the Danish Register of Causes of Death, ambulance and hospital patient files. Adjudication of the diagnosis was done by two local experts and one external senior cardiologist. RESULTS: A total of 2766 of the 246.723 adult residents in the region had died. A type 3 myocardial infarction was diagnosed in 18...... individuals, corresponding to an annual incidence of 7.3/100.000 person years. During the same one-year period 488 patients had other types of myocardial infarction implying a 3.6% frequency of type 3 myocardial infarction (18 of 506) among all myocardial infarctions. CONCLUSIONS: Type 3 myocardial infarction...... is a rare observation in clinical practice with an annual incidence below 10/100.000 person years and a frequency of 3-4% among all types of myocardial infarction. If autopsy data are included the number of type 3 myocardial infarctions will increase....

Exploiting Affine Invariant Regions and Leaf Edge Shapes for Weed Detection

DEFF Research Database (Denmark)

Kazmi, Wajahat; Ruiz, Francisco Garcia; Nielsen, Jon

2015-01-01

. Then a comparison with the field data retrieval highlighted the trade-off due to the field challenges. Adopting a comprehensive approach, edge shape detectors and homogeneous surface detecting affine invariant regions were fused. In order to integrate vegetation indices as local features, a new local vegetation...

Mitral regurgitation in myocardial infarction complicated by heart failure, left ventricular dysfunction, or both: prognostic significance and relation to ventricular size and function

DEFF Research Database (Denmark)

Amigoni, Maria; Meris, Alessandra; Thune, Jens Jakob

2007-01-01

AIMS: Mitral regurgitation (MR) confers independent risk in patients with acute myocardial infarction. We utilized data from the VALsartan In Acute myocardial iNfarcTion echo study to relate baseline MR to left ventricular (LV) size, shape, and function, and to assess the relationship between...

Tomographic myocardial perfusion scintigraphy in children with Kawasaki disease

International Nuclear Information System (INIS)

Spielmann, R.P.; Nienaber, C.A.; Hausdorf, G.; Montz, R.

1987-01-01

Myocardial infarction and stenotic coronary lesions are serious late complications in children with Kawasaki disease. For the noninvasive assessment of myocardial perfusion, dipyridamole-redistribution 201 Tl emission computed tomography (ECT) was performed in seven children (age 2 8/12-8 7/12 yr) 3-20 mo after the acute stage of the disease. In all patients, coronary aneurysms had been demonstrated by cross-sectional echocardiography. The scintigrams of six children showed no significant regional reduction of myocardial thallium uptake. These children had remained asymptomatic since the acute stage of Kawasaki disease. Persistent and transient thallium defects were present in one child with documented myocardial infarction. For this patient, obstruction of corresponding coronary vessels was confirmed by contrast angiography. It is suggested, that 201 Tl ECT after dipyridamole-induced vasodilation may be used as a safe alternative to invasive coronary angiography for follow-up investigations in patients with Kawasaki disease

Serial thallium-201 imaging after dipyridamole for coronary disease detection: quantitative analysis using myocardial clearance

International Nuclear Information System (INIS)

Okada, R.D.; Dai, Y.H.; Boucher, C.A.; Pohost, G.M.

1984-01-01

After dipyridamole, canine studies have demonstrated a slower rate of myocardial thallium-201 clearance from zones distal to a coronary artery stenosis compared to normal zones. To determine if criteria based on canine myocardial thallium-201 clearance rates could be applied clinically, 40 patients with and 26 patients without coronary artery disease (CAD) had serial thallium-201 images obtained for 2 to 5 hours after dipyridamole. Regions of interest were manually placed over six left ventricular segments in two projections for each of three imaging times. The myocardial thallium-201 clearance rate was calculated for each of the six segments and, using the clearance rate criterion found in canine studies, was considered abnormal if less than 6.5%/hr. Using this criterion alone, 22 of 26 patients (85%) without CAD had normal and 30 of 40 patients (75%) with CAD had abnormal myocardial thallium-201 clearance rates. A quantitative analysis of regional inhomogeneity in tracer distribution (normal was greater than or equal to 25% difference between segments) was negative in 24 of 26 patients (92%) without CAD and positive in 20 of 40 patients (50%) with CAD. When both clearance rate and regional inhomogeneity were considered, 21 of 26 patients (81%) without CAD had negative and 36 of 40 patients (90%) with CAD had positive results. Thus, post-dipyridamole myocardial clearance rate criteria derived from canine studies can be applied to clinical thallium imaging. Quantitative analysis of serial thallium-201 images after dipyridamole is optimized by using myocardial thallium-201 clearance rates. Such an approach is independent of regional inhomogeneities in tracer distribution

Clinical indications for Thallium-201 myocardial perfusion scanning

International Nuclear Information System (INIS)

Dunn, R.J.; Kelly, D.T.

1982-01-01

Thallium-201 myocardial perfusion scanning can assess regional myocardial perfusion non-invasively. As it is both time-consuming and expensive its use should be restricted to specific diagnostic problems. The clinical indications in known or suspected coronary artery disease are reviewed. In suspected coronary artery disease thallium scanning is most useful in patients with chest pain when the exercise ECG is uninterpretable, in men with probable angina but a negative exercise ECG, or conversely a positive exercise ECG without typical angina, and in women with probable angina and either a positive or a negative exercise ECG. In known coronary artery disease, thallium scanning may help determine the functional significance of a coronary obstruction found at angiography and may determine the site of myocardial ischaemia when multiple obstructions are present

MR tomography in myocardial ischaemia: present state of the art

International Nuclear Information System (INIS)

Szolar, D.H.; Saeed, M.; Higgins, C.B.

1996-01-01

Recent developments in MR imaging have opened up new avenues in the investigation of ischaemic heart disease. Conventional unenhanced spin-echo sequences have been used to detect and quantify myocardial infarction. Along with the technical advances aimed at reducing motion artifacts and imaging time, the advent of contrast media for MR imaging has further strengthened its diagnostic capacities. The applications of MR contrast media are increasing, and they are becoming more specific, to enable differentiation of occlusive and reperfused myocardial infarctions and to discriminate between reversible and irreversible myocardial injury. Previous studies have also indicated that dual administration of both relaxivity-based and susceptibility-based contrast media can be used to determine whether viable myocardium is present in the reperfused ischaemic area. Magnetic susceptibility MR contrast media have the potential to demonstrate a region of the ischaemically injured myocardium in which myocardial necrosis is present. A cornestone in the MR assessment of ischaemic heart disease has been achieved with the advent of fast MR imaging techniques. Ultrafast gradient-recalled-echo sequences or echoplanar imaging allow to monitor the first passage of the contrast medium through the heart. With the aid of MR contrast media, these techniques may be useful in estimating regional myocardial perfusion and blood volume. Experimental and clinical perfusion studies indicate that perfusion-sensitive MR imaging, particularly in concert with coronary vasodilators, can detect compromised myocardium. Combining myocardial perfusion imaging with the anatomic and functional information provided by other MR imaging techniques such as cine and velocity-encoded sequences could make MR imaging a comprehensive noninvasive diagnostic tool for the assessment of ischaemic heart disease. (orig.) [de

Effect of glucose-insulin-potassium infusion on thallium myocardial clearance

International Nuclear Information System (INIS)

Wilson, R.A.; Okada, R.D.; Strauss, H.W.; Pohost, G.M.

1983-01-01

Factors influencing the rate of 201 Tl clearance from the myocardium have not been clearly defined. This study determined the effect of an intravenous infusion of glucose-insulin-potassium (GIK) on the net 201 Tl clearance rates from myocardium with and without initial 201 Tl loading. Anesthetized open-chest dogs underwent 5 min of left anterior descending coronary artery occlusion and intravenous 201 Tl was injected and the occlusion released 5 min later. Thirty minutes after 201 Tl injection, 30 ml of either GIK (nine dogs) or saline (five dogs) was infused intravenously. The clearance rates of 201 Tl from the anterior wall (without initial 201 Tl loading) and from the posterior wall (with initial 201 Tl loading) were monitored with miniaturized cadmium telluride detectors placed on the myocardium. Calculation of net myocardial clearance rates was performed by linear regression analysis from serial 1 min counts. Compared with saline infusion, GIK increased the net clearance of 201 Tl from both myocardial regions with and without initial loading. The most marked change induced by GIK infusion was in the myocardial region without initial 201 Tl loading; a net increase in 201 Tl activity (72 +/- 42 cpm/30 min) was converted into a net loss (-594 +/- 228 cpm/30 min). There was no significant change in 201 Tl clearance after the saline infusion. Heart rate, aortic and left atrial pressure, sonomicrometer-measured transmural myocardial wall thickness, microsphere-determined myocardial blood flow, and blood glucose and potassium concentrations did not change significantly during GIK or saline infusions. Thus, GIK infusion appears to increase net 201 Tl clearance from myocardial zones with and without initial 201 Tl loading

Myocardial viability assessed with fluorodeoxyglucose and PET in patients with Q wave myocardial infarction receiving thrombolysis: relationship to coronary anatomy and ventricular function.

Science.gov (United States)

Fragasso, G; Chierchia, S L; Rossetti, E; Sciammarella, M G; Conversano, A; Lucignani, G; Landoni, C; Calori, G; Margonato, A; Fazio, F

1997-03-01

In previously thrombolysed patients, we analysed residual myocardial viability using the PET-FDG technique and correlated its presence and extent to the angiographic appearance of the infarct-related vessel and left ventricular function. Thirty-six patients who had undergone intravenous thromboloysis for acute myocardial infarction 4.8 +/- 7.2 months previously were studied. Coronary angiography, left ventriculography, and assessment of myocardial perfusion and metabolism were all performed within 1 week. All patients exhibited perfusion defects consistent with the clinically identified myocardial infarction site. Residual viability, as assessed by the PET-FDG technique, was present in 53% of cases. The infarct-related coronary artery was patent in 19 (53%) patients (TIMI grade 3, 79%); of the remaining 17 with occluded infarct-related arteries, 11 had collaterals to the infarct area. Significant FDG uptake was observed in 63% of patients with a patent infarct-related artery and in 41% of those with an occluded infarct-related artery. The same study protocol was adopted in a control group of 30 patients with myocardial infarction who did not receive thrombolysis. The number of infarct-related patent vessels was significantly lower in these patients (30 vs 53%) (TIMI grade 3, 56%), but the overall percentage of PET viability was again 53%. Qualitative analysis of the regional perfusion pattern showed that the magnitude and severity of the perfusion defect was similar in the two groups, regardless of the presence or absence of FDG uptake. Global left ventricular function was also similar in the two groups. However, regional wall motion was significantly better in the thrombolysed patients with a patent infarct-related artery than in those who had not received thrombolysis and whose culprit vessel was also patent. In conclusion, the results of our study support the notion that early recanalization of the infarct-related artery is critical for preserving left

Clinical evaluation of myocardial involvement in acute myopericarditis in young adults.

Science.gov (United States)

Saricam, Ersin; Saglam, Yasemin; Hazirolan, Tuncay

2017-05-22

Myocardial involvement in young adults has various causes. Acute myopericarditis is one of the myocardial involvements in young adults. It is easy to confuse with acute ST-elevation myocardial infarction because of the electrocardiographic features. This study aims to investigate a number of imaging techniques and clinical features for acute myopericarditis in young adults (defined as myocardial brightness in the left ventricle regions, especially in posterior and lateral wall. Focal echobright was observed in the 75 of 77 cases of acute myopericarditis in transthoracic echocardiogram. This sign was confirmed by cardiac magnetic resonance imaging. Focal echobright sensitivity was 95%; its specificity was 93%; its predictive was 95.2%. Pericardial effusion (83%) was observed in group I behind posterior wall. Its specificity was 81%; its sensitivity was 65%; predictivity was 73%. Pericardial effusion and myocardial focal echobright in echocardiography can be quite sensitive indicators for acute myopericarditis in young adults.

Heart deformation analysis for automated quantification of cardiac function and regional myocardial motion patterns: A proof of concept study in patients with cardiomyopathy and healthy subjects

Energy Technology Data Exchange (ETDEWEB)

Lin, Kai, E-mail: kai-lin@northwestern.edu; Collins, Jeremy D.; Chowdhary, Varun; Markl, Michael; Carr, James C.

2016-10-15

Highlights: • Heart deformation analysis (HDA) can quantify global and regional cardiac function. • HDA works based on cine CMR images without the needs of operator interaction. • HDA-derived cardiac motion indices are reproducible. - Abstract: Objective: To test the performance of HDA in characterizing left ventricular (LV) function and regional myocardial motion patterns in the context of cardiomyopathy based on cine cardiovascular magnetic resonance (CMR). Materials and methods: Following the approval of the institutional review board (IRB), standard cine images of 45 subjects, including 15 healthy volunteers, 15 patients with hypertrophic cardiomyopathy (HCM) and 15 patients with dilated cardiomyopathy (DCM) were retrospectively analyzed using HDA. The variations of LV ejection fraction (LVEF), LV mass (LVM), and regional myocardial motion indices, including radial (Drr), circumferential (Dcc) displacement, radial (Vrr) and circumferential (Vcc) velocity, radial (Err), circumferential (Ecc) and shear (Ess) strain and radial (SRr) and circumferential (SRc) strain rate, were calculated and compared among subject groups. Inter-study reproducibility of HDA-derived myocardial motion indices were tested on 15 volunteers by using intra-class correlation coefficient (ICC) and coefficient of variation (CoV). Results: HDA identified significant differences in cardiac function and motion indices between subject groups. DCM patients had significantly lower LVEF (33.5 ± 9.65%), LVM (105.88 ± 21.93 g), peak Drr (0.29 ± 0.11 cm), Vrr-sys (2.14 ± 0.72 cm/s), Err (0.17 ± 0.08), Ecc (−0.08 ± 0.03), SRr-sys (0.91 ± 0.44s{sup −1}) and SRc-sys (−0.64 ± 0.27s{sup −1}) compared to the other two groups. HCM patients demonstrated increased LVM (171.69 ± 34.19) and lower peak Vcc-dia (0.78 ± 0.30 cm/s) than other subjects. Good inter-study reproducibility was found for all HDA-derived myocardial indices in healthy volunteers (ICC = 0.664–0.942, CoV = 15.1%–37

Heart deformation analysis for automated quantification of cardiac function and regional myocardial motion patterns: A proof of concept study in patients with cardiomyopathy and healthy subjects

International Nuclear Information System (INIS)

Lin, Kai; Collins, Jeremy D.; Chowdhary, Varun; Markl, Michael; Carr, James C.

2016-01-01

Highlights: • Heart deformation analysis (HDA) can quantify global and regional cardiac function. • HDA works based on cine CMR images without the needs of operator interaction. • HDA-derived cardiac motion indices are reproducible. - Abstract: Objective: To test the performance of HDA in characterizing left ventricular (LV) function and regional myocardial motion patterns in the context of cardiomyopathy based on cine cardiovascular magnetic resonance (CMR). Materials and methods: Following the approval of the institutional review board (IRB), standard cine images of 45 subjects, including 15 healthy volunteers, 15 patients with hypertrophic cardiomyopathy (HCM) and 15 patients with dilated cardiomyopathy (DCM) were retrospectively analyzed using HDA. The variations of LV ejection fraction (LVEF), LV mass (LVM), and regional myocardial motion indices, including radial (Drr), circumferential (Dcc) displacement, radial (Vrr) and circumferential (Vcc) velocity, radial (Err), circumferential (Ecc) and shear (Ess) strain and radial (SRr) and circumferential (SRc) strain rate, were calculated and compared among subject groups. Inter-study reproducibility of HDA-derived myocardial motion indices were tested on 15 volunteers by using intra-class correlation coefficient (ICC) and coefficient of variation (CoV). Results: HDA identified significant differences in cardiac function and motion indices between subject groups. DCM patients had significantly lower LVEF (33.5 ± 9.65%), LVM (105.88 ± 21.93 g), peak Drr (0.29 ± 0.11 cm), Vrr-sys (2.14 ± 0.72 cm/s), Err (0.17 ± 0.08), Ecc (−0.08 ± 0.03), SRr-sys (0.91 ± 0.44s −1 ) and SRc-sys (−0.64 ± 0.27s −1 ) compared to the other two groups. HCM patients demonstrated increased LVM (171.69 ± 34.19) and lower peak Vcc-dia (0.78 ± 0.30 cm/s) than other subjects. Good inter-study reproducibility was found for all HDA-derived myocardial indices in healthy volunteers (ICC = 0.664–0.942, CoV = 15.1%–37

Functional modulation of cardiac form through regionally confined cell shape changes.

Directory of Open Access Journals (Sweden)

Heidi J Auman

2007-03-01

Full Text Available Developing organs acquire a specific three-dimensional form that ensures their normal function. Cardiac function, for example, depends upon properly shaped chambers that emerge from a primitive heart tube. The cellular mechanisms that control chamber shape are not yet understood. Here, we demonstrate that chamber morphology develops via changes in cell morphology, and we determine key regulatory influences on this process. Focusing on the development of the ventricular chamber in zebrafish, we show that cardiomyocyte cell shape changes underlie the formation of characteristic chamber curvatures. In particular, cardiomyocyte elongation occurs within a confined area that forms the ventricular outer curvature. Because cardiac contractility and blood flow begin before chambers emerge, cardiac function has the potential to influence chamber curvature formation. Employing zebrafish mutants with functional deficiencies, we find that blood flow and contractility independently regulate cell shape changes in the emerging ventricle. Reduction of circulation limits the extent of cardiomyocyte elongation; in contrast, disruption of sarcomere formation releases limitations on cardiomyocyte dimensions. Thus, the acquisition of normal cardiomyocyte morphology requires a balance between extrinsic and intrinsic physical forces. Together, these data establish regionally confined cell shape change as a cellular mechanism for chamber emergence and as a link in the relationship between form and function during organ morphogenesis.

Direct myocardial perfusion imaging in valvular heart disease

Energy Technology Data Exchange (ETDEWEB)

Soto, R.C.; Durante, M.L.; Villacorta, E.V.; Torres, J.F.; Monzon, O.P.

1981-02-01

Twenty two patients with rheumatic valvular heart disease - 21 having a history of heart failure - were studied using direct coronary injection of /sup 99m/Tc labelled MAA particles during the course of hemodynamic and arteriographic studies. Myocardial perfusion deficit patterns have been shown to be consistent or indicative of either patchy, regional or gross ischemia. In patients with history of documented heart failure 90% (18 cases) had ischemic perfusion deficit in the involved ventricle. We conclude that diminished myocardial blood flow is an important mechanism contributing to the development of heart failure.

Direct myocardial perfusion imaging in valvular heart disease

International Nuclear Information System (INIS)

Soto, R.C.; Durante, M.L.; Villacorta, E.V.; Torres, J.F.; Monzon, O.P.

1981-01-01

Twenty two patients with rheumatic valvular heart disease - 21 having a history of heart failure - were studied using direct coronary injection of sup(99m)Tc labelled MAA particles during the course of hemodynamic and arteriographic studies. Myocardial perfusion deficit patterns have been shown to be consistent or indicative of either patchy, regional or gross ischemia. In patients with history of documented heart failure 90% (18 cases) had ischemic perfusion deficit in the involved ventricle. We conclude that diminished myocardial blood flow is an important mechanism contributing to the development of heart failure. (orig.) [de

Myocardial perfusion modeling using MRI

DEFF Research Database (Denmark)

Larsson, H B; Fritz-Hansen, T; Rostrup, Egill

1996-01-01

In the present study, it is shown that it is possible to quantify myocardial perfusion using magnetic resonance imaging in combination with gadolinium diethylenetriaminopentaacetic acid (Gd-DTPA). Previously, a simple model and method for measuring myocardial perfusion using an inversion recovery...... turbo-FLASH (fast low-angle shot) sequence and Gd-DTPA has been presented. Here, an extension of the model is presented taking into account fast and slow water exchange between the compartments, enabling the calculation of the unidirectional influx constant (Ki) for Gd-DTPA, the distribution volume...... of Gd-DTPA (lambda), the vascular blood volume (Vb), and the time delay through the coronary arteries (delta T). The model was evaluated by computer simulation and used on experimental results from seven healthy subjects. The results in the healthy volunteers for a region of interest placed...

A serial changes of thallium-201 myocardial images in a patient with nontransmural myocardial infarction

International Nuclear Information System (INIS)

Tanaka, Takeshi; Itoh, Yukiyoshi; Takayama, Yasuo

1986-01-01

A 66 year old man had suffered from inferior myocardial infarction one year ago and then suffered from effort angina. Recently rest angina attack frequently occurred and he was admitted because of angina attack refractory to TNG. The patient was diagnosed as broad nontransmural infarction. A serial thallium-201 myocardial imagings at rest and thallium-201 lung uptake imagings were performed and some interesting findings were obtained as followings. Myocardial imagings on 3rd day after admission showed no significant deffect, however EF was 34 %. Immediately after severe ischemic attack marked defect was noted at posterolateral region and ECG showed prominent precordial ST depression without accompanying significant ST change in II, III, aVF. On 3rd day after severe attack under hemodynamically and electrocardiographically stable state posterolateral defect improved, though still persisted. EF was 28 %. On 3rd day postop no marked defects were noted in myocardial imagings, so posterolateral defect at rest after severe ischemic attack was proved to be transient defect. In this case thallium-201 lung uptake was not noted before attack. Immediately after severe attack thallium lung uptake increased and maximal uptake was noted at basal zone of lung, however in chest X-P typical butterfly shadow was noted at upper zone of lung. On 3rd day after severe attack hemodynamics improved and butterfly shadow ceased, though thallium lung uptake increased and noted at upper zone of lung. After operation thallium lung uptake improved. (J.P.N.)

Myocardial infarction after dipyridamole-assisted thallium-201 imaging

International Nuclear Information System (INIS)

Biddle, P.; Lanspa, T.J.; Mohiuddin, S.M.; Malesker, M.A.; Hilleman, D.E.

1989-01-01

A 77-year-old woman with suspected coronary artery disease underwent an oral dipyridamole/thallium-201 myocardial imaging study. Approximately 75 minutes after ingestion of dipyridamole 300 mg suspension, the patient developed chest pain, hypotension, nausea, and diaphoresis. An electrocardiogram revealed ST-T wave changes suggestive of inferior ischemia. Appropriate therapeutic measures, including aminophylline and nitroglycerin, were instituted. Delayed thallium images revealed reversible ischemia in the anteroseptal and posterobasal regions with a fixed defect in the inferobasal region. Cardiac enzyme studies were also indicative of acute myocardial injury. The patient subsequently underwent coronary arteriography and four-vessel coronary artery bypass grafting and was discharged without further complication. This report raises concerns about the potential danger of dipyridamole in patients with severe coronary artery stenosis and collateral circulation. Prophylactic aminophylline should be considered in these patients

A Regions of Confidence Based Approach to Enhance Segmentation with Shape Priors.

Science.gov (United States)

Appia, Vikram V; Ganapathy, Balaji; Abufadel, Amer; Yezzi, Anthony; Faber, Tracy

2010-01-18

We propose an improved region based segmentation model with shape priors that uses labels of confidence/interest to exclude the influence of certain regions in the image that may not provide useful information for segmentation. These could be regions in the image which are expected to have weak, missing or corrupt edges or they could be regions in the image which the user is not interested in segmenting, but are part of the object being segmented. In the training datasets, along with the manual segmentations we also generate an auxiliary map indicating these regions of low confidence/interest. Since, all the training images are acquired under similar conditions, we can train our algorithm to estimate these regions as well. Based on this training we will generate a map which indicates the regions in the image that are likely to contain no useful information for segmentation. We then use a parametric model to represent the segmenting curve as a combination of shape priors obtained by representing the training data as a collection of signed distance functions. We evolve an objective energy functional to evolve the global parameters that are used to represent the curve. We vary the influence each pixel has on the evolution of these parameters based on the confidence/interest label. When we use these labels to indicate the regions with low confidence; the regions containing accurate edges will have a dominant role in the evolution of the curve and the segmentation in the low confidence regions will be approximated based on the training data. Since our model evolves global parameters, it improves the segmentation even in the regions with accurate edges. This is because we eliminate the influence of the low confidence regions which may mislead the final segmentation. Similarly when we use the labels to indicate the regions which are not of importance, we will get a better segmentation of the object in the regions we are interested in.

Quantitative analysis of thallium-201 myocardial scintigraphy

International Nuclear Information System (INIS)

Kanemoto, Nariaki; Hoer, G.; Johost, S.; Maul, F.-D.; Standke, R.

1981-01-01

The method of quantitative analysis of thallium-201 myocardial scintigraphy using computer assisted technique was described. Calculated indices are washout factor, vitality index and redistribution factor. Washout factor is the ratio of counts at certain period of time after exercise and immediately after exercise. This value is neccessary for the evaluation of redistribution to the ischemic areas in serial imagings to correct the Tl-201 washout from the myocardium under the assumption that the washout is constant in the whole myocardium. Vitality index is the ratio between the Tl-201 uptake in the region of interest and that of the maximum. Redistribution factor is the ratio of the redistribution in the region of interest in serial imagings after exercise to that of immediately after exercise. Four examples of exercise Tl-201 myocardial scintigrams and the quantitative analyses before and after the percutaneous transluminal coronary angioplasty were presented. (author)

Assessment of myocardial viability by exercise stress myocardial tomography with 201Tl

International Nuclear Information System (INIS)

Narita, Michihiro; Kurihara, Tadashi; Murano, Kenichi; Usami, Masahisa

1992-01-01

Exercise stress (Ex) and redistribution (RD) myocardial tomography with Tl-201 has been widely used for evaluating myocardial viability. But recent studies have demonstrated that reinjection (ReI) study following RD study is necessary for detecting reversible ischemic myocardium. On the other hand, decreased myocardial washout of Tl-201 after Ex is an indicator of myocardial ischemia. So we have studied the usefulness of myocardial Tl-201 washout rate (WOR) for the evaluation of myocardial viability by comparing it with ReI images. Ex and RD myocardial tomographies were obtained immediately after Ex and 3 hours later. After RD study a small amount of Tl-201 was injected and ReI imaging was repeated. We studied 64 myocardial segments (in 58 patients with coronary artery disease) in which Ex-induced perfusion defects persisted in RD images. According to the changes of perfusion defects between Ex, RD and ReI images, they were classified into 3 types: Type I; perfusion defect on the RD image was identical to ReI image (75%). Type I was divided into 2 subgroups whether perfusion defect at Ex was unchanged (Ia, 42%) or improved (Ib, 33%) on the RD image. Type II; perfusion defect at Ex was reduced on the RD image and it improved furthermore at ReI image (17%). Type III; perfusion defect was the same at Ex and RD but it was reduced on the ReI image (8%). WOR less than 30% was defined as abnormal when Ex heart rate exceeded 120 bpm and lung-myocardial Tl-201 uptake ratio was less than 0.45. The differentiation between Type Ia and Type III is of great importance. History of myocardial infarction, effort angina and Ex induced ST depression could not differentiate these 2 groups. WOR abnormality was observed in all of Type III, but WOR was normal in Type Ia. In conclusion, WOR abnormality in Ex-RD myocardial imaging is useful for evaluating myocardial viability. ReI imaging is necessary for the precise evaluation of viable muscle mass and for inadequate Ex. (author)

Heterogeneous composite bodies with isolated lenticular shaped cermet regions

Science.gov (United States)

Sherman, Andrew J [Cirtland Hills, OH

2009-12-22

A heterogeneous body having ceramic rich cermet regions in a more ductile metal matrix. The heterogeneous bodies are formed by thermal spray operations on metal substrates. The thermal spray operations apply heat to a cermet powder and project it onto a solid substrate. The cermet powder is composed of complex composite particles in which a complex ceramic-metallic core particle is coated with a matrix precursor. The cermet regions are generally comprised of complex ceramic-metallic composites that correspond approximately to the core particles. The cermet regions are approximately lenticular shaped with an average width that is at least approximately twice the average thickness. The cermet regions are imbedded within the matrix phase and generally isolated from one another. They have obverse and reverse surfaces. The matrix phase is formed from the matrix precursor coating on the core particles. The amount of heat applied during the formation of the heterogeneous body is controlled so that the core particles soften but do not become so fluid that they disperse throughout the matrix phase. The force of the impact on the surface of the substrate tends to flatten them. The flattened cermet regions tend to be approximately aligned with one another in the body.

201Tl uptake in variant angina: probable demonstration of myocardial reactive hyperemia in man

International Nuclear Information System (INIS)

Kronenberg, M.W.; Robertson, R.M.; Born, M.L.; Steckley, R.A.; Robertson, D.; Friesinger, G.C.

1982-01-01

Myocardial thallium scintigraphy was performed in four subjects with variant angina and in one subject with isolated, fixed coronary obstruction. Three subjects with variant angina had short episodes of ischemic ST-segment elevation that lasted 20--100 seconds. Thallium scintigrams demonstrated excess uptake in regions judged to be ischemic by angiographic and electrocardiographic criteria. Two subjects, one with variant angina and the other with a fixed coronary lesion, had prolonged episodes of ischemia that lasted 390--900 seconds. Both had reduced thallium uptake in the ischemic regions. We conclude that myocardial reactive hyperemia is the cause of excess thallium uptake in patients with variant angina who have short episodes of myocardial ischemia

Identification of acute myocardial infarction with MR imaging by using combined assessment of regional wall motion and Gd-DTPA uptake

International Nuclear Information System (INIS)

Roos, A. de; Matheijssen, N.A.A.; Doornbos, J.; van Dijkman, P.; Pattynama, P.; van der Wall, E.

1990-01-01

This paper evaluates the usefulness of MR imaging for identification of acute myocardial infarction (AMI) in clinical patients, based on the assessment of regional wall motion abnormalities in conjunction with local uptake of Gd-DTPA. Fourteen patients with proved AMI and 12 normal volunteers underwent multisection-multiphase MR imaging in the short-axis plane encompassing the entire left ventricle. Gd-DTPA (0.2 mmol/kg) was injected in all patients to enhance the infarcted region. MR cine loops of the patients and volunteers were blinded and displayed. Three experienced observers scored the cine loops in consensus as to the presence or absence of AMI, noting wall motion abnormalities and/or increased Gd-DTPA uptake

Different Causes of Death in Patients with Myocardial Infarction Type 1, Type 2, and Myocardial Injury.

Science.gov (United States)

Lambrecht, Sascha; Sarkisian, Laura; Saaby, Lotte; Poulsen, Tina S; Gerke, Oke; Hosbond, Susanne; Diederichsen, Axel C P; Thygesen, Kristian; Mickley, Hans

2018-05-01

Data outlining the mortality and the causes of death in patients with type 1 myocardial infarction, type 2 myocardial infarction, and those with myocardial injury are limited. During a 1-year period from January 2010 to January 2011, all hospitalized patients who had cardiac troponin I measured on clinical indication were prospectively studied. Patients with at least one cardiac troponin I value >30 ng/L underwent case ascertainment and individual evaluation by an experienced adjudication committee. Patients were classified as having type 1 myocardial infarction, type 2 myocardial infarction, or myocardial injury according to the criteria of the universal definition of myocardial infarction. Follow-up was ensured until December 31, 2014. Data on mortality and causes of death were obtained from the Danish Civil Registration System and the Danish Register of Causes of Death. Overall, 3762 consecutive patients were followed for a mean of 3.2 years (interquartile range 1.3-3.6 years). All-cause mortality differed significantly among categories: Type 1 myocardial infarction 31.7%, type 2 myocardial infarction 62.2%, myocardial injury 58.7%, and 22.2% in patients with nonelevated troponin values (log-rank test; P causes, vs 42.6% in patients with type 2 myocardial infarction (P = .015) and 41.2% in those with myocardial injury (P causes of death did not differ substantially between patients with type 2 myocardial infarction and those with myocardial injury. Patients with type 2 myocardial infarction and myocardial injury exhibit a significantly higher long-term mortality compared with patients with type 1 myocardial infarction . However, most patients with type 1 myocardial infarction die from cardiovascular causes in contrast to patients with type 2 myocardial infarction and myocardial injury, in whom noncardiovascular causes of death predominate. Copyright © 2018 Elsevier Inc. All rights reserved.

Monitoring of myocardial edema following acute myocardial infarction

International Nuclear Information System (INIS)

Tahir, E.; Sinn, M.; Avanesov, M.; Wien, J.; Saering, D.; Stehning, C.; Radunski, U. K.; Muellerleile, K.; Adam, G.; Lund, G. K.

2015-01-01

Full text: Currently, myocardial edema monitoring after acute myocardial infarction (AMI) is based on visualization of the region with increased signal-intensity on T2-weighted images. Native T1 and T2 mapping are promising novel MRI techniques to quantitatively assess myocardial edema. The purpose of the study was to quantitatively evaluate resorption of myocardial edema following AMI by native T1 and T2 -mapping cardiac magnetic resonance imaging (CMR). CMR (1.5 Tesla Philips Achieva) was performed in 30 patients four times after reperfused AMI at baseline (BL) at 9±6 days after infarction and at 7±1 weeks (follow-up 1, FU1), 3.6±0.5 months (FU2) and 6.5±0.7 months (FU3), respectively. Edema sensitive black-blood T2-weighted (T2w) STIR CMR was performed on end-diastolic LV short-axes. A free-breathing, navigatorgated multi-echo sequence was used for short-axis T2 mapping. T1 mapping was performed using the modified look-locker inversion recovery (MOLLI) sequence. T2 maps were calculated from nine and T1 maps from eight echoes using a dedicated plug-in written for OsiriX software. Two experienced observers independently evaluated T2w-CMR as well as T1 and T2 mapping using the HeAT-Software applying a threshold method. Size of edema and prolongation of the native T1- or T2-time was measured using a cutoff >2SD of remote normal myocardium. Edema size continuously decreased from BL with 32.8 %LV to 24.6 %LV at FU1, to 19.1 %LV at FU2 and to 16.4 %LV at FU3 using T2w-CMR. An almost identical decrease of edema size was observed using native T1 and T2 - mapping. T2 times only decreased between BL from 79±5 ms to 73±2 ms at FU1 (P<0.05), but no further change was observed at later time points with 70±5 ms at FU2 and 70±6 ms at FU3. At all time points the T2 times of remote normal myocardium were about 50±2 ms and significantly lower compared to the edema zone. Also native T1 time within the edema was with 1253 ±103 ms significantly increased compared to remote

Line-shape asymmetry of water vapor absorption lines in the 720-nm wavelength region

Science.gov (United States)

Grossmann, Benoist E.; Browell, Edward V.

1991-01-01

Spectral line-shape analyses were performed for water vapor lines broadened by argon, oxygen, and xenon in the 720-nm wavelength region. A line-shape asymmetry was observed, which is attributed to statistical dependence or correlation between velocity- and state-changing collisions. The generalized (asymmetric) Galatry profile, which results from the soft-collision profile and includes correlation between velocity- and state-changing collisions, was fitted to the observed line shapes and was found to compare favorably with the observed data. The most prominent asymmetries were observed with xenon as the buffer gas.

Myocardial imaging. Coxsackie myocarditis

Energy Technology Data Exchange (ETDEWEB)

Wells, R.G.; Ruskin, J.A.; Sty, J.R.

1986-09-01

A 3-week-old male neonate with heart failure associated with Coxsackie virus infection was imaged with Tc-99m PYP and TI-201. The abnormal imaging pattern suggested myocardial infarction. Autopsy findings indicated that the cause was myocardial necrosis secondary to an acute inflammatory process. Causes of abnormal myocardial uptake of Tc-99m PYP in pediatrics include infarction, myocarditis, cardiomyopathy, bacterial endocarditis, and trauma. Myocardial imaging cannot provide a specific cause diagnosis. Causes of myocardial infarction in pediatrics are listed in Table 1.

Myocardial imaging. Coxsackie myocarditis

International Nuclear Information System (INIS)

Wells, R.G.; Ruskin, J.A.; Sty, J.R.

1986-01-01

A 3-week-old male neonate with heart failure associated with Coxsackie virus infection was imaged with Tc-99m PYP and TI-201. The abnormal imaging pattern suggested myocardial infarction. Autopsy findings indicated that the cause was myocardial necrosis secondary to an acute inflammatory process. Causes of abnormal myocardial uptake of Tc-99m PYP in pediatrics include infarction, myocarditis, cardiomyopathy, bacterial endocarditis, and trauma. Myocardial imaging cannot provide a specific cause diagnosis. Causes of myocardial infarction in pediatrics are listed in Table 1

Study progress of cardiac MRI technology in assessment of myocardial viability after myocardial infarction

International Nuclear Information System (INIS)

Wang Jing; Zhang Hao

2013-01-01

Acute myocardial infarction (AMI) is one of the most common diseases that cause disability and death around the world. Correctly and effectively assessing the myocardial viability after myocardial infarction can reduce the disabled rate and mortality rate. At present, many methods could be used to assess myocardial viability. The cardiac magnetic resonance imaging (CMR) technology has a lot of advantages compared to other methods. In this paper, we reviewed the research progress of CMR in assessment of myocardial viability after myocardial infarction, and compared CMR with other technologies. (authors)

The diagnosis of silent myocardial ischemia. Motion-Frozen (or morphing) myocardial perfusion imaging.

Science.gov (United States)

Chang, Cheng; Ye, Bo; Xie, Wenhui; Zhang, Daoliang; Lei, Bei; Ye, Xiaodan

2016-01-01

Silent myocardial ischemia is typically defined as objective evidence of myocardial ischemia in patients without subjective ischemia symptoms. Currently, coronary artery angiography is the gold standard for diagnosis of asymptomatic coronary artery disease (CAD). Computed tomography coronary angiography (CTCA) can visually demonstrate the morphology, trend and extent of coronary stenosis and is commonly used in clinical screening of CAD. Myocardial perfusion imaging can be used not only to identify whether anatomical stenosis causes myocardial dysfunction, but to also assess the risk stratification and prognosis of myocardial disease (MD). Myocardial perfusion imaging using morphing combined with CTCA can simultaneously show the relationship between CAD and myocardial ischemia from an anatomical and functional aspect. This allows earlier diagnosis of asymptomatic CAD myocardial ischemia, accurate identification of the culprit vessels, and could prevent unnecessary interventional therapy. The 1-day dobutamine stress/resting met-hod is also one of the methods used. The combination of CTCA and the morphing technique can provide anatomical and functional information on coronary arteries at the same time, significantly improving the diagnostic sensitivity, specificity, and accuracy of MD.

Clinical evaluation of the Tl-201 ECG-gated myocardial SPECT

International Nuclear Information System (INIS)

Mochizuki, Teruhito

1989-01-01

In order to evaluate the clinical usefulness of the Tl-201 ECG-gated myocardial single photon emission computed tomography (SPECT), we compared the wall motion and the grade of the Tl-201 uptake of the ECG-gated myocardial SPECT with the wall motion of the ECG-gated blood pool SPECT. Materials were 87 patients of 50 old myocardial infarctions (OMIs), 19 hypertrophic cardiomyopathies (HCMs), 2 dilated cardiomyopathies (DCMs) and 16 others. After intravenous injection of 111-185 MBq (3-5 mCi) of Tl-201 at rest, the projection data were acquired using a rotating gamma-camera through 180deg, from RAO 45deg in 24 directions, each of which consisted of 80-100 beats. For the reconstruction of ED, ES and non-gated images, R-R interval was divided into about 20 (18-22) fractions. In 348 regions of interest (anterior, septal, lateral and inferior wall) in 87 cases, wall motion and the Tl-201 uptake were evaluated to three grades (normal, hypokinesis and akinesis; normal, low and defect, respectively), which were compared with the wall motion of the ECG-gated blood pool SPECT. The wall motion and the grade of the Tl-201 uptake of the ECG-gated myocardial SPECT correlated well with the wall motion of the ECG-gated blood pool SPECT (96.6% and 87.9%, respectively). In conclusion, the ECG-gated myocardial SPECT can provide clear perfusion images and is a very useful diagnostic strategy to evaluate the regional wall motion and perfusion simultaneously. (author)

Screening for silent myocardial ischemia caseof diabetics : interest of myocardial perfusion scintigraphy

International Nuclear Information System (INIS)

Bahri, Haifa

2007-01-01

Silent myocardial ischemia is a major cause of morbidity and mortality in diabetic patients. Its diagnosis by noninvasive means such as myocardial SPECT would improve the management of these patients. The purpose of this study is to assess the frequency of silent myocardial ischemia in asymptomatic diabetics and their evolution. As a result, the myocardial SPECT is a reliable tool for screening for silent myocardial ischemia in diabetic patients. Its prognostic value allows to stratify the cardiac risk and guide therapeutic management. Its integration into a screening strategy in Tunisia seems limited by its low availability and cost. The latter could be reduced by better patient selection.

Periodontitis and myocardial hypertrophy.

Science.gov (United States)

Suzuki, Jun-Ichi; Sato, Hiroki; Kaneko, Makoto; Yoshida, Asuka; Aoyama, Norio; Akimoto, Shouta; Wakayama, Kouji; Kumagai, Hidetoshi; Ikeda, Yuichi; Akazawa, Hiroshi; Izumi, Yuichi; Isobe, Mitsuaki; Komuro, Issei

2017-04-01

There is a deep relationship between cardiovascular disease and periodontitis. It has been reported that myocardial hypertrophy may be affected by periodontitis in clinical settings. Although these clinical observations had some study limitations, they strongly suggest a direct association between severity of periodontitis and left ventricular hypertrophy. However, the detailed mechanisms between myocardial hypertrophy and periodontitis have not yet been elucidated. Recently, we demonstrated that periodontal bacteria infection is closely related to myocardial hypertrophy. In murine transverse aortic constriction models, a periodontal pathogen, Aggregatibacter actinomycetemcomitans markedly enhanced cardiac hypertrophy with matrix metalloproteinase-2 activation, while another pathogen Porphyromonas gingivalis (P.g.) did not accelerate these pathological changes. In the isoproterenol-induced myocardial hypertrophy model, P.g. induced myocardial hypertrophy through Toll-like receptor-2 signaling. From our results and other reports, regulation of chronic inflammation induced by periodontitis may have a key role in the treatment of myocardial hypertrophy. In this article, we review the pathophysiological mechanism between myocardial hypertrophy and periodontitis.

Dobutamine cardiovascular magnetic resonance for the detection of myocardial ischemia with the use of myocardial tagging.

Science.gov (United States)

Kuijpers, Dirkjan; Ho, Kai Yiu J A M; van Dijkman, Paul R M; Vliegenthart, Rozemarijn; Oudkerk, Matthijs

2003-04-01

The purpose of this study was to assess the value of high-dose dobutamine cardiovascular magnetic resonance (CMR) with myocardial tagging for the detection of wall motion abnormalities as a measure of myocardial ischemia in patients with known or suspected coronary artery disease. Two hundred eleven consecutive patients with chest pain underwent dobutamine-CMR 4 days after antianginal medication was stopped. Dobutamine-CMR was performed at rest and during increasing doses of dobutamine. Cine-images were acquired during breath-hold with and without myocardial tagging at 3 short-axis levels. Regional wall motion was assessed in a 16-segment short-axis model. Patients with new wall motion abnormalities (NWMA) were examined by coronary angiography. Dobutamine-CMR was successfully performed in 194 patients. Dobutamine-CMR without tagging detected NWMA in 58 patients, whereas NWMA were detected in 68 patients with tagging (P=0.002, McNemar). Coronary angiography showed coronary artery disease in 65 (96%) of these 68 patients. All but 3 of the 65 patients needed revascularization. In the 112 patients with a negative dobutamine-CMR study, without baseline wall motion abnormalities, the cardiovascular occurrence-free survival rate was 98.2% during the mean follow-up period of 17.3 months (range, 7 to 31). Dobutamine-CMR with myocardial tagging detected more NWMA compared with dobutamine-CMR without tagging and reliably separated patients with a normal life expectancy from those at increased risk of major adverse cardiac events.

Angiographically demonstrated coronary collaterals predict residual viable myocardium in patients with chronic myocardial infarction. A regional metabolic study

International Nuclear Information System (INIS)

Fukai, Masumi; Ii, Masaaki; Nakakoji, Takahiro

2000-01-01

Angiographical demonstration of coronary collateral circulation may suggest the presence of residual viable myocardium. The development of coronary collaterals was judged according to Rentrop's classification in 37 patients with old anteroseptal myocardial infarction and 13 control patients with chest pain syndrome. The subjects with myocardial infarction were divided into 2 groups: 17 patients with the main branch of the left coronary artery clearly identified by collateral blood flow from the contralateral coronary artery [Coll (+) group, male/female 10/7, mean age 56.6 years] and 20 patients with obscure coronary trunk [Coll (-) group, male/female 16/4, mean age 54.9 years]. Thallium-201 myocardial scintigraphy and examination of local myocardial metabolism were carried out by measuring the flux of lactic acid under dipyridamole infusion load. Coronary stenosis of 99% or total occlusion was found in only 5 of 20 patients (25%) in the Coll (-) group but in 16 of 17 patients (94%) in the Coll (+) group (p<0.001). Redistribution of myocardial scintigraphy was found in 11 of 15 patients (73%) in the Coll (+) group, but only 3 of 18 patients (17%) in the Coll (-) group (p<0.01). The myocardial lactic acid extraction rate was -13.2±17.0% in the Coll (+) group, but 9.1±13.2% in the Coll (-) group (p<0.001). These results suggest that coronary collateral may contribute to minimizing the infarct area and to prediction of the presence of viable myocardium. (author)

The clinical application value of myocardial perfusion imaging in evaluating coronary artery myocardial bridge patients with symptoms

International Nuclear Information System (INIS)

Wang Yuetao; Fu Ning; Ding Xuemei; Lu Cunzhi; Zhu Feng; Wang Guanmin; Huang Yijie; Wang Linguang

2008-01-01

Objective: Myocardial bridge is a common inborn coronary artery anomaly, myocardial bridge may be associated with myocardial ischemia. Only a few patients with coronary artery myocardial bridge were evaluated with nuclear medicine techniques. The aim of this study was to investigate the role of nuclear cardiology with myocardial perfusion technique in symptomatic myocardial bridge patients. Methods Nineteen myocardial bridge patients with the symptoms of chest pain and chest distress were analyzed retrospectively. 99 Tc m -methoxyisobutylisonitrile (MIBI) myocardial perfusion images (both exercise and rest) were performed in all. Imaging results were compared with the results of movement electrocardiogram (ECG) and coronary arteriography. The t test or χ 2 test was used to statistically analyze the data with Stata 7.0 software. Results: Of the 19 patients, 18 patients had myocardial bridge locating at the left anterior descending artery, 1 patient at the left anterior descending and left circumflex artery, the mean angiographic systolic occlusion within the myocardial bridge was (65.4 ± 22.1)%. Of these 19 patients, Exercise-rest 99 Tc m -MIBI myocardial perfusion imaging defined positive myocardial ischemia in 10 and negative in 9 patients. Of the 10 patients with 99 Tc m -MIBI myocardial perfusion imaging defined myocardial ischemia, 8 had reversible radioactive defect of partial anterior wall and (or) apex, 1 had reversible defect of post lateral wall and post septal wall, and 1 had reversible defect of inferior wall. The positive predictive value of myocardial perfusion imaging was 52.6% (10/19), which was higher than movement ECG [21.1% (4/19), χ 2 = 4.07, P 99 Tc m -MIBI myocardial periusion imaging defined myocardial ischemia. Six cases with Grade II stenosis, two were 99 Tc m -MIBI myocardial perfusion imaging defined myocardial ischemia. Eight cases with Grade III stenosis, seven were 99 Tc m -MIBI myocardial perfusion imaging defined myocardial

Intravenous Administration of Lycopene, a Tomato Extract, Protects against Myocardial Ischemia-Reperfusion Injury.

Science.gov (United States)

Tong, Chao; Peng, Chuan; Wang, Lianlian; Zhang, Li; Yang, Xiaotao; Xu, Ping; Li, Jinjin; Delplancke, Thibaut; Zhang, Hua; Qi, Hongbo

2016-03-03

Oral uptake of lycopene has been shown to be beneficial for preventing myocardial ischemia-reperfusion (I/R) injury. However, the strong first-pass metabolism of lycopene influences its bioavailability and impedes its clinic application. In this study, we determined an intravenous (IV) administration dose of lycopene protects against myocardial infarction (MI) in a mouse model, and investigated the effects of acute lycopene administration on reactive oxygen species (ROS) production and related signaling pathways during myocardial I/R. In this study, we established both in vitro hypoxia/reoxygenation (H/R) cell model and in vivo regional myocardial I/R mouse model by ligating left anterior artery descending. TTC dual staining was used to assess I/R induced MI in the absence and presence of acute lycopene administration via tail vein injection. Lycopene treatment (1 μM) before reoxygenation significantly reduced cardiomyocyte death induced by H/R. Intravenous administration of lycopene to achieve 1 μM concentration in circulating blood significantly suppressed MI, ROS production, and JNK phosphorylation in the cardiac tissue of mice during in vivo regional I/R. Elevating circulating lycopene to 1 μM via IV injection protects against myocardial I/R injury through inhibition of ROS accumulation and consequent inflammation in mice.

Continuous determination of regional myocardial blood flow with intracoronary krypton-81m in coronary artery disease

International Nuclear Information System (INIS)

Remme, W.J.; Krauss, X.H.; van Hoogenhuyze, D.C.; Cox, P.H.; Storm, C.J.; Kruyssen, D.A.

1985-01-01

Pacing-induced changes in regional coronary flow were studied continuously with krypton-81m by intracoronary infusion in 25 patients: 21 with 50% or greater diameter narrowing of 1 or more left coronary arteries (group I) and 4 with less than 50% diameter reduction of a left coronary artery (group II). No changes occurred in group II. In group I, krypton-81m perfusion decreased progressively in all areas with more than 70% diameter narrowing, with a simultaneous increase in normal regions. At the end of pacing during angina, krypton-81m perfusion was reduced to 81 +/- 4% of control in areas with 71 to 90% diameter reduction (n = 8) and to 69 +/- 6% in areas with more than 90% diameter narrowing (n = 15). In contrast, in regions with 50 to 70% diameter reduction changes were variable (decrease in 4 regions, increase in 2 and an unchanged distribution in 1 region). Krypton-81m perfusion decreased early, before general signs of ischemia in areas with more than 90% diameter reduction, whereas this decrease occurred later in regions with 71 to 90% diameter narrowing, concurrently with ST-segment changes but before anginal pain. Although all signs of ischemia had disappeared between 2 and 5 minutes after pacing, changes in krypton-81m distribution persisted in most areas for 5 to 15 minutes after pacing. It is concluded that the functional significance of coronary arterial narrowing can be assessed with a continuous intracoronary infusion of krypton-81m. Changes in regional distribution persisted after cessation of pacing-induced ischemia, indicating an ongoing decrease in regional myocardial blood flow

Evaluation of the differences of myocardial fibers between acute and chronic myocardial infarction: Application of diffusion tensor magnetic resonance imaging INA Rhesus monkey model

Energy Technology Data Exchange (ETDEWEB)

Wang, Yu Qing; Cai, Wei; Wang, Lei; Xia, Rui; Chen, Wei; Zheng, Jie [Dept. of Radiology, West China Hospital, Sichuan University, Sichuan (China); Gao, Fabao [Mallinckrodt Institute of Radiology, School of Medicine, Washington University, St. Louis (United States)

2016-09-15

To understand microstructural changes after myocardial infarction (MI), we evaluated myocardial fibers of rhesus monkeys during acute or chronic MI, and identified the differences of myocardial fibers between acute and chronic MI. Six fixed hearts of rhesus monkeys with left anterior descending coronary artery ligation for 1 hour or 84 days were scanned by diffusion tensor magnetic resonance imaging (MRI) to measure apparent diffusion coefficient (ADC), fractional anisotropy (FA) and helix angle (HA). Comparing with acute MI monkeys (FA: 0.59 ± 0.02; ADC: 5.0 ± 0.6 × 10{sup -4} mm{sup 2}/s; HA: 94.5 ± 4.4°), chronic MI monkeys showed remarkably decreased FA value (0.26 ± 0.03), increased ADC value (7.8 ± 0.8 × 10{sup -4} mm{sup 2}/s), decreased HA transmural range (49.5 ± 4.6°) and serious defects on endocardium in infarcted regions. The HA in infarcted regions shifted to more components of negative left-handed helix in chronic MI monkeys (-38.3 ± 5.0°–11.2 ± 4.3°) than in acute MI monkeys (-41.4 ± 5.1°–53.1 ± 3.7°), but the HA in remote regions shifted to more components of positive right-handed helix in chronic MI monkeys (-43.8 ± 2.7°–66.5 ± 4.9°) than in acute MI monkeys (-59.5 ± 3.4°–64.9 ± 4.3°). Diffusion tensor MRI method helps to quantify differences of mechanical microstructure and water diffusion of myocardial fibers between acute and chronic MI monkey's models.

Evaluation of the differences of myocardial fibers between acute and chronic myocardial infarction: Application of diffusion tensor magnetic resonance imaging INA Rhesus monkey model

International Nuclear Information System (INIS)

Wang, Yu Qing; Cai, Wei; Wang, Lei; Xia, Rui; Chen, Wei; Zheng, Jie; Gao, Fabao

2016-01-01

To understand microstructural changes after myocardial infarction (MI), we evaluated myocardial fibers of rhesus monkeys during acute or chronic MI, and identified the differences of myocardial fibers between acute and chronic MI. Six fixed hearts of rhesus monkeys with left anterior descending coronary artery ligation for 1 hour or 84 days were scanned by diffusion tensor magnetic resonance imaging (MRI) to measure apparent diffusion coefficient (ADC), fractional anisotropy (FA) and helix angle (HA). Comparing with acute MI monkeys (FA: 0.59 ± 0.02; ADC: 5.0 ± 0.6 × 10 -4 mm 2 /s; HA: 94.5 ± 4.4°), chronic MI monkeys showed remarkably decreased FA value (0.26 ± 0.03), increased ADC value (7.8 ± 0.8 × 10 -4 mm 2 /s), decreased HA transmural range (49.5 ± 4.6°) and serious defects on endocardium in infarcted regions. The HA in infarcted regions shifted to more components of negative left-handed helix in chronic MI monkeys (-38.3 ± 5.0°–11.2 ± 4.3°) than in acute MI monkeys (-41.4 ± 5.1°–53.1 ± 3.7°), but the HA in remote regions shifted to more components of positive right-handed helix in chronic MI monkeys (-43.8 ± 2.7°–66.5 ± 4.9°) than in acute MI monkeys (-59.5 ± 3.4°–64.9 ± 4.3°). Diffusion tensor MRI method helps to quantify differences of mechanical microstructure and water diffusion of myocardial fibers between acute and chronic MI monkey's models

Is myocardial fatty acid metabolism different between hypertrophic cardiomyopathy and hypertensive hypertrophy?

International Nuclear Information System (INIS)

Narita, Michihiro; Kurihara, Tadashi; Usami, Masahisa; Honda, Minoru

1994-01-01

To investigate characteristics of fatty acid metabolism in hypertrophic cardiomyopathy (HCM), we performed myocardial imaging with 123 I-iodophenyl-3-methylpentadecanoic acid (BMIPP) in 24 HCM patients, 13 patients with hypertensive hypertrophy (HT) and 10 normal subjects. Rest myocardial imaging with 123 I-BMIPP was obtained at 20 minutes and 3 hours after 123 I-BMIPP injection. Rest 201 Tl imaging was also performed. In addition to ordinary tomography, whole body imaging was performed to calculate %Uptake (percentage of cardiac uptake of the isotope to total injected dose). As global indexes of fatty acid metabolism, we calculated two parameters; Uptake Ratio (%Uptake of 123 I-BMIPP normalized by myocardial perfusion) and WOR (percent reduction of myocardial 123 I-BMIPP within 3 hours). Regional abnormality was evaluated by visual assessment of ordinary tomograms and by BMIPP/Tl map. BMIPP/Tl map was made from Bull's-eye maps of 123 I-BMIPP and 201 Tl, and it represented 123 I-BMIPP uptake normalized by myocardial perfusion of each pixel which constructed the image. %Uptake of 123 I-BMIPP was not different among three groups. Uptake Ratio was significantly (p HT (1.03±0.08)>HCM (0.87±0.09). WOR of 123 I-BMIPP was accerelated in HCM (12.7±4.7%) and HT (10.2±2.9%) compared with normal (5.1±3.1%) (p 123 I-BMIPP distribution was found in 17 of 24 patients (71%) including 3 patients with equivocal abnormality. In HT patients, only equivocal abnormality was observed in 23%. In BMIPP/Tl map, abnormality was observed in 92% of HCM and 8% of HT. Although global myocardial fatty acid metabolism was equally disturbed both in HCM and HT, regional abnormality of fatty acid metabolism was observed preferetially in HCM. This indicated myocardial fatty acid metabolism was not identical between HCM and HT. (author)

Clinical Characteristics and Outcomes of Patients with Myocardial Infarction, Myocardial Injury, and Nonelevated Troponins

DEFF Research Database (Denmark)

Sarkisian, Laura; Saaby, Lotte; Poulsen, Tina S

2016-01-01

BACKGROUND: Cardiac troponins have emerged as the preferred biomarkers for detecting myocardial necrosis and diagnosing myocardial infarction. However, current cardiac troponin assays do not discriminate between ischemic and nonischemic causes of myocardial cell death. Thus, when an increased...... troponin value is encountered in the absence of obvious myocardial ischemia, a careful search for other clinical conditions is crucial. METHODS: In 2010 to 2011, we prospectively studied hospitalized patients who had cardiac troponin I measured on clinical indication. An acute myocardial infarction...... was diagnosed in cases of a cardiac troponin I increase or decrease pattern with at least 1 value >30 ng/L (99th percentile) together with myocardial ischemia. Myocardial injury was defined as cardiac troponin I values >30 ng/L, but without signs or symptoms indicating overt cardiac ischemia. Patients with peak...

Global and regional left ventricular function and tomographic radionuclide perfusion: the Western Washington Intracoronary Streptokinase In Myocardial Infarction Trial

International Nuclear Information System (INIS)

Ritchie, J.L.; Davis, K.B.; Williams, D.L.; Caldwell, J.; Kennedy, J.W.

1984-01-01

The Western Washington Intracoronary Streptokinase In Myocardial Infarction Trial enrolled 250 patients with acute myocardial infarction. After the coronary angiographic diagnosis of thrombosis, patients were randomly assigned to receive either conventional therapy with heparin or intracoronary streptokinase followed by heparin. Of the 232 patients who survived at least 60 days, 207 (89%) underwent radionuclide ventriculographic determination of global and regional ejection fraction at a single institution at 62 +/- 35 days after infarction. In the first 100 patients, infarct size was also determined by quantitative single-photon emission tomographic imaging with thallium-201 ( 201 Tl) and expressed as a percentage of the left ventricle with a perfusion defect. Overall, global ejection fraction did not differ between patients treated with streptokinase (45.9 +/- 13.9%; n . 115) and control patients (46.1 +/- 14.4%; n . 92, p . NS). Similarly, the regional posterolateral, inferior, and anteroseptal ejection fraction did not differ between the two groups. Infarct size as measured by 201 Tl tomography was 19.4 +/- 12.8% (n . 52) of the left ventricle for the streptokinase group and 19.6 +/- 11.8% (n . 48; p . NS) for the control group. When patients were compared within groups by electrocardiographic location of infarction, time to treatment, or the presence or absence of vessel opening, there were no significant differences between streptokinase and control patients. Statistical inclusion of the 18 patients who died early and were unavailable for study also failed to modify the results, except for a possible reduction in inferior infarct size as measured by 201 Tl tomography

Clinical evaluation of 123I-BMIPP myocardial scintigraphy in patients with hypertrophic cardiomyopathy

International Nuclear Information System (INIS)

Ohtsuki, Katsuichi; Sugihara, Hiroki; Umamoto, Ikuo

1992-01-01

123 I-β-methyl-p-iodophenylpentadecanoic acid ( 123 I-BMIPP) myocardial scintigraphy was performed in 13 patients with hypertrophic cardiomyopathy and compared with 201 Tl myocardial scintigraphy performed within 3 months for evaluating the clinical significance of 123 I-BMIPP myocardial scintigraphy. SPECT images were divided into 13 segments and segmental images were visually scored on a 4 (increased tracer uptake) to 0 (severely decreased tracer uptake) scale according to the tracer uptake. In comparison of 123 I-BMIPP early images and 201 Tl perfusion images, mismatches were seen in about 70% of all segments. The number of segments demonstrating lower myocardial uptake of 123 I-BMIPP was larger than that of 201 Tl. In hypertrophic regions, the tracer uptake of 123 I-BMIPP early images was significantly lower than that of 201 Tl images and the lower uptake of 123 I-BMIPP delayed images was more marked. In non-hypertrophic regions, no significant difference was seen between the tracer uptakes of 123 I-BMIPP early images and 201 Tl images but the tracer uptake of 123 I-BMIPP delayed images was significantly lower than that of 201 Tl images. The mismatch between the tracer uptakes of 123 I-BMIPP images and 201 Tl images was thought to be a reflection of disordered myocardial fatty acid metabolism. 'Washout', the difference between the tracer uptakes of 123 I-BMIPP early images and delayed images was also thought to be a reflection of disordered myocardial fatty acid metabolism. These results suggest that 123 I-BMIPP is a promising radiopharmaceutical for evaluating disordered myocardial fatty acid metabolism in patients with HCM. (author)

Preoperative evaluation of myocardial viability by thallium-201 imaging in patients with old myocardial infarction who underwent coronary revascularization

International Nuclear Information System (INIS)

Naruse, Hitoshi; Ohyanagi, Mitsumasa; Iwasaki, Tadaaki; Miyamoto, Takashi; Fukuchi, Minoru

1992-01-01

The myocardial uptake and redistribution in thallium scintigraphy and the regional wall motion by echocardiography were evaluated by a semi-quantitative method in 42 patients who previously had myocardial infarction (50 target vessels) and underwent coronary revascularization. The aim of this study was to elucidate the significance of the initial image, delayed image and redistribution on thallium-201 scintigraphy for clinical diagnosis of the myocardial viability. As a semi-quantitative analysis, we used a bull's-eye display for thallium image and centerline method for echocardiographic wall motion, and compared the results before and after revascularization. As a result, the thallium grade improved postoperatively in all 17 areas which preoperatively had showed redistribution, and also in 11 of the 32 areas without preoperative redistribution. The sensitivity, specificity and accuracy of preoperative thallium redistribution for predicting myocardial viability were 61%, 100% and 78%, respectively, when the postoperative improvement in the thallium grade was used as the standard. The postoperative probability of improvement in the thallium grade increased in proportion to the preoperative grade (delayed image)(p<0.01). There was no correlation between the preoperative thallium delayed image and postoperative improvement in wall motion. Postoperative improvement in thallium image and wall motion could not be predicted from the preoperative wall motion. Thus, postoperative improvement in thallium images can be anticipated if redistribution is present on the preoperative thallium image, and the preoperative thallium delayed image is useful for predicting myocardial viability. Improvement in wall motion could not be predicted preoperatively by these methods. (author)

Robust Myocardial Motion Tracking for Echocardiography: Variational Framework Integrating Local-to-Global Deformation

Directory of Open Access Journals (Sweden)

Chi Young Ahn

2013-01-01

Full Text Available This paper proposes a robust real-time myocardial border tracking algorithm for echocardiography. Commonly, after an initial contour of LV border is traced at one or two frames from the entire cardiac cycle, LV contour tracking is performed over the remaining frames. Among a variety of tracking techniques, optical flow method is the most widely used for motion estimation of moving objects. However, when echocardiography data is heavily corrupted in some local regions, the errors bring the tracking point out of the endocardial border, resulting in distorted LV contours. This shape distortion often occurs in practice since the data acquisition is affected by ultrasound artifacts, dropouts, or shadowing phenomena of cardiac walls. The proposed method is designed to deal with this shape distortion problem by integrating local optical flow motion and global deformation into a variational framework. The proposed descent method controls the individual tracking points to follow the local motions of a specific speckle pattern, while their overall motions are confined to the global motion constraint being approximately an affine transform of the initial tracking points. Many real experiments show that the proposed method achieves better overall performance than conventional methods.

Application of 123I-labelled long-chained fatty acids for the study of myocardial metabolism

International Nuclear Information System (INIS)

Freundlieb, C.; Hoeck, A.; Vyska, F.; Feinendegen, L.E.; Machulla, H.J.; Stoecklin, G.

1978-01-01

Radioiodine-labelled fatty acids are useful tracers for myocardial imaging. The present study extends myocardial scintigraphy with ω-123-I-heptadecanoic acid to measuring myocardial metabolism. 4 normal individuals and 6 patients with cardiac disease received i.v. 1-2 mCi ω-123-I-heptadecanoic acid. Immediately fast serial scintigrams of the myocardium were taken for 30 minutes. Disappearance of the tracer, and appearance of anorganic 123-I, was measured in the peripheral blood. The myocardial images were of high quality later than 5 minutes after injection. By correcting for anorganic 123-I in the peripheral blood and the interstitium, the turnover of tracer in the myocardial cells could be measured. Activity was lost from the myocardium with a half time between 14 and 32 minutes. Within regions of old myocardials infarctions the half time of tracer loss was prolonged. The data clearly indicate the feasibility of using ω-123-I-heptadecanoic acid for measuring myocardial metabolism. (author)

Evaluation of the Differences of Myocardial Fibers between Acute and Chronic Myocardial Infarction: Application of Diffusion Tensor Magnetic Resonance Imaging in a Rhesus Monkey Model

Energy Technology Data Exchange (ETDEWEB)

Wang, Yuqing [Department of Radiology, West China Hospital, Sichuan University, Sichuan 610041 (China); CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, National Center for Nanoscience and Technology of China, Beijing 100190 (China); Cai, Wei [Department of Radiology, West China Hospital, Sichuan University, Sichuan 610041 (China); Department of Radiology, Beijing Jishuitan Hospital, 4th Clinical Medical College of Peking University, Beijing 100035 (China); Wang, Lei [Department of Radiology, West China Hospital, Sichuan University, Sichuan 610041 (China); Xia, Rui [Department of Radiology, West China Hospital, Sichuan University, Sichuan 610041 (China); Department of Radiology, The First Affiliated Hospital, Chongqing Medical University, Chongqing 400016 (China); Chen, Wei [Department of Radiology, West China Hospital, Sichuan University, Sichuan 610041 (China); Department of Radiology, The First Affiliated Hospital of Kunming Medical University, Yunnan 650032 (China); Zheng, Jie [Mallinckrodt Institute of Radiology, School of Medicine, Washington University, St. Louis, MO 63110 (United States); Gao, Fabao [Department of Radiology, West China Hospital, Sichuan University, Sichuan 610041 (China)

2016-11-01

To understand microstructural changes after myocardial infarction (MI), we evaluated myocardial fibers of rhesus monkeys during acute or chronic MI, and identified the differences of myocardial fibers between acute and chronic MI. Six fixed hearts of rhesus monkeys with left anterior descending coronary artery ligation for 1 hour or 84 days were scanned by diffusion tensor magnetic resonance imaging (MRI) to measure apparent diffusion coefficient (ADC), fractional anisotropy (FA) and helix angle (HA). Comparing with acute MI monkeys (FA: 0.59 ± 0.02; ADC: 5.0 ± 0.6 × 10{sup -4} mm{sup 2}/s; HA: 94.5 ± 4.4°), chronic MI monkeys showed remarkably decreased FA value (0.26 ± 0.03), increased ADC value (7.8 ± 0.8 × 10{sup -4}mm{sup 2}/s), decreased HA transmural range (49.5 ± 4.6°) and serious defects on endocardium in infarcted regions. The HA in infarcted regions shifted to more components of negative left-handed helix in chronic MI monkeys (-38.3 ± 5.0°–11.2 ± 4.3°) than in acute MI monkeys (-41.4 ± 5.1°–53.1 ± 3.7°), but the HA in remote regions shifted to more components of positive right-handed helix in chronic MI monkeys (-43.8 ± 2.7°–66.5 ± 4.9°) than in acute MI monkeys (-59.5 ± 3.4°–64.9 ± 4.3°). Diffusion tensor MRI method helps to quantify differences of mechanical microstructure and water diffusion of myocardial fibers between acute and chronic MI monkey's models.

Diagnostic value of exercise induced 18F-FDG myocardial metabolism scintigraphy in myocardial ischemia

International Nuclear Information System (INIS)

Shen Rui; He Zuoxiang; Shi Rongfang; Liu Xiujie; Tian Yueqin; Guo Feng; Wei Hongxing; Wu Yongjian; Qin Xuewen; Gao Runlin

2006-01-01

Objective: To evaluate the feasibility and diagnostic accuracy of exercise induced myocardial imaging with 18 F-fluorodeoxyglucose (FDG) in myocardial ischemia. Methods: Twenty-six patients with known or suspected coronary artery, disease (CAD) and with no prior myocardial infarction underwent simultaneous myocardial perfusion and metabolism imaging following intravenous injection of 99 Tc m -methoxy-isobutylisonitrile ( 99 Tc m -sestamibi) and 18 F-FDG at peak exercise. Subsequently rest perfusion imaging and coronary angiography (CAG) were performed in all patients. Exercise 18 F-FDG myocardial imaging was compared with 99 Tc m -sestamibi imaging and CAG. Results: In 22 patients with ≥50% narrowing over l coronary artery, 18 had perfusion abnormalities (sensitivity 82%), whereas 20 had abnormal myocardial 18 F-FDG uptake (sensitivity 91%, P>0.05). Patients with reversible (12 cases) or partial reversible (3 cases) perfusion abnormalities had increased myocardial 18 F-FDG uptake in abnormal perfusion segments. Compared with CAG, perfusion defect was seen in myocardial segments corresponding to 25 vascular territories of 51 vessels with ≥50% narrowing in 22 patients in 99 Tc m -sestamibi imaging (sensitivity 49%), whereas increased 18 F-FDG uptake was seen in 34 vascular territories (sensitivity 67%, P=0.008). Conclusions: Exercise induced myocardial ischemia can be imaged directly with 18 F-FDG. Combined exercise 18 F-FDG and 99 Tc m -sestamibi imaging provides a better assessment of exercise-induced myocardial ischemia as compared with exercise-rest perfusion imaging. (authors)

Localization and quantification of acute myocardial infarction by myocardial perfusion tomographic imaging

International Nuclear Information System (INIS)

Lin Xiufang; Min Changgeng; Lin Zhihu; Ke Ruoyi

1994-01-01

The authors reported the result of the quantification and localization of 30 clinically confirmed acute myocardial infarction patients in comparison with that of ECG. A left ventricle model was used to correct the area calculated by the method of Bull's eye. The result indicated that the infarction area calculated by the corrected Bull's eye method correlated closely with that determined by the ECG QRS scoring method (r = 0.706, P<0.01). Myocardial infarctions of all 30 patients were detected by both ECG and myocardial perfusion tomographic imaging. The accuracy of localization of myocardial infarction by myocardial perfusion imaging was similar to that of ECG in the anterior wall, anterior septum, anterior lateral and inferior wall, but superior to that of ECG in the apex, posterior lateral, posterior septum, and posterior wall

In vivo study of myocardial elastography under graded ischemia conditions

Energy Technology Data Exchange (ETDEWEB)

Lee, Wei-Ning; Provost, Jean; Konofagou, Elisa E [Department of Biomedical Engineering, Columbia University, New York, NY (United States); Fujikura, Kana [Department of Radiology, Columbia University, New York, NY (United States); Wang Jie, E-mail: ek2191@columbia.edu [Department of Medicine, Columbia University, New York, NY (United States)

2011-02-21

The capability of currently available echocardiography-based strain estimation techniques to fully map myocardial abnormality at early stages of myocardial ischemia is yet to be investigated. In this study, myocardial elastography (ME), a radio-frequency (RF)-based strain imaging technique that maps the full 2D transmural angle-independent strain tensor in standard echocardiographic views at both high spatial and temporal resolution is presented. The objectives were to (1) evaluate the performance of ME on mapping the onset, extent and progression of myocardial ischemia at graded coronary constriction levels (from partial to complete coronary flow reduction), and (2) validate the accuracy of the strain estimates against sonomicrometry (SM) measurements. A non-survival canine ischemic model (n = 5) was performed by gradually constricting the left anterior descending (LAD) coronary blood flow from 0% (baseline blood flow) to 100% (zero blood flow) at 20% increments. An open-architecture ultrasound system was used to acquire RF echocardiograms in a standard full short-axis view at the frame rate of 211 fps, at least twice higher than what is typically used in conventional echocardiographic systems, using a previously developed, fully automated composite technique. Myocardial deformation was estimated by ME and validated against sonomicrometry. ME estimates and maps transmural (1) 2D displacements using RF cross-correlation and recorrelation; and (2) 2D polar (radial and circumferential) strains, derived from 2D (i.e. both lateral and axial) displacement components, at high accuracy. Full-view strain images were shown and found to reliably depict decreased myocardial function in the region at risk at increased levels of coronary flow reduction. The ME radial strain was deemed to be a more sensitive, quantitative, regional measure of myocardial ischemia as a result of coronary flow reduction when compared to the conventional wall motion score index and ejection fraction

Classification of myocardial infarction

DEFF Research Database (Denmark)

Saaby, Lotte; Poulsen, Tina Svenstrup; Hosbond, Susanne Elisabeth

2013-01-01

The classification of myocardial infarction into 5 types was introduced in 2007 as an important component of the universal definition. In contrast to the plaque rupture-related type 1 myocardial infarction, type 2 myocardial infarction is considered to be caused by an imbalance between demand...

Relation of plasma lipoprotein(a) with myocardial viability and left ventricular performance in survivors of myocardial infarction

International Nuclear Information System (INIS)

Aksoy, M.; Goktekin, O.; Gursurer, M.; Emre, A.; Bilge, M.; Yesilcimen, K.; Ersek, B.; Kepekci, Y.; Akdemir, I.

1999-01-01

Previous studies have reported that high serum lipoprotein(a) levels may be responsible for total occlusion of the infarct-related artery via inhibition of intrinsic fibrinolysis during acute myocardial infarction. We evaluated whether this would result in a greater extent of myocardial necrosis and impaired left ventricular function in patients with high lipoprotein(a) levels. Sixty-eight patients with prior myocardial infarction, who were not receiving thrombolytic therapy underwent coronary angiography and stress-redistribution-reinjection Tl-201 scintigraphy. Antegrade TIMI flow in the infarct-related artery was lower (1.54±1.14 vs 2.15±1.05; p=0.03) and the collateral index was higher (1.3±1.0 vs 0.8±0.9; p=0.07) in patients with high lipoprotein(a) levels (>30 mg/dl) compared to those with low lipoprotein(a) levels (≤30 mg/dl). Regional wall motion score index was lower (0.8±0.8 vs 1.4±0.5; p=0.008) and global ejection fraction was higher (46±10% vs 40±11%; p=0.03) in patients with low lipoprotein(a) levels. On SPECT images, the number of nonviable defects was higher in patients with high lipoprotein(a) levels (4.0±2.5 vs 1.9±1.3; p=0.0002), whereas the number of viable defects was higher in those with low lipoprotein(a) levels (2.5±1.8 vs 1.5±1.3; p=0.02). We conclude, that high lipoprotein(a) levels may prolong the occlusion of infarct-related artery during acute myocardial infarction and lead to a greater extent of myocardial necrosis and impaired left ventricular function. (author)

Direct Evidence that Myocardial Insulin Resistance following Myocardial Ischemia Contributes to Post-Ischemic Heart Failure

Science.gov (United States)

Fu, Feng; Zhao, Kun; Li, Jia; Xu, Jie; Zhang, Yuan; Liu, Chengfeng; Yang, Weidong; Gao, Chao; Li, Jun; Zhang, Haifeng; Li, Yan; Cui, Qin; Wang, Haichang; Tao, Ling; Wang, Jing; Quon, Michael J; Gao, Feng

2015-01-01

A close link between heart failure (HF) and systemic insulin resistance has been well documented, whereas myocardial insulin resistance and its association with HF are inadequately investigated. This study aims to determine the role of myocardial insulin resistance in ischemic HF and its underlying mechanisms. Male Sprague-Dawley rats subjected to myocardial infarction (MI) developed progressive left ventricular dilation with dysfunction and HF at 4 wk post-MI. Of note, myocardial insulin sensitivity was decreased as early as 1 wk after MI, which was accompanied by increased production of myocardial TNF-α. Overexpression of TNF-α in heart mimicked impaired insulin signaling and cardiac dysfunction leading to HF observed after MI. Treatment of rats with a specific TNF-α inhibitor improved myocardial insulin signaling post-MI. Insulin treatment given immediately following MI suppressed myocardial TNF-α production and improved cardiac insulin sensitivity and opposed cardiac dysfunction/remodeling. Moreover, tamoxifen-induced cardiomyocyte-specific insulin receptor knockout mice exhibited aggravated post-ischemic ventricular remodeling and dysfunction compared with controls. In conclusion, MI induces myocardial insulin resistance (without systemic insulin resistance) mediated partly by ischemia-induced myocardial TNF-α overproduction and promotes the development of HF. Our findings underscore the direct and essential role of myocardial insulin signaling in protection against post-ischemic HF. PMID:26659007

Temperature, air pollution, and mortality from myocardial infarction in São Paulo, Brazil

Directory of Open Access Journals (Sweden)

Sharovsky R.

2004-01-01

Full Text Available An increase in daily mortality from myocardial infarction has been observed in association with meteorological factors and air pollution in several cities in the world, mainly in the northern hemisphere. The objective of the present study was to analyze the independent effects of environmental variables on daily counts of death from myocardial infarction in a subtropical region in South America. We used the robust Poisson regression to investigate associations between weather (temperature, humidity and barometric pressure, air pollution (sulfur dioxide, carbon monoxide, and inhalable particulate, and the daily death counts attributed to myocardial infarction in the city of São Paulo in Brazil, where 12,007 fatal events were observed from 1996 to 1998. The model was adjusted in a linear fashion for relative humidity and day-of-week, while nonparametric smoothing factors were used for seasonal trend and temperature. We found a significant association of daily temperature with deaths due to myocardial infarction (P < 0.001, with the lowest mortality being observed at temperatures between 21.6 and 22.6ºC. Relative humidity appeared to exert a protective effect. Sulfur dioxide concentrations correlated linearly with myocardial infarction deaths, increasing the number of fatal events by 3.4% (relative risk of 1.03; 95% confidence interval = 1.02-1.05 for each 10 µg/m³ increase. In conclusion, this study provides evidence of important associations between daily temperature and air pollution and mortality from myocardial infarction in a subtropical region, even after a comprehensive control for confounding factors.

Quantitative estimation of myocardial thickness by the wall thickness map with Tl-201 myocardial SPECT and its clinical use

International Nuclear Information System (INIS)

Sekiai, Yasuhiro; Sawai, Michihiko; Murayama, Susumu

1988-01-01

To estimate the wall thickness of left ventricular myocardium objectively and quantitatively, we adopted the device of wall thickness map (WTM) with Tl-201 myocardial SPECT. For validation on measuring left ventricular wall thickness with SPECT, fundamental studies were carried out with phantom models, and clinical studies were performed in 10 cases comparing the results from SPECT with those in echocardiography. To draw the WTM, left ventricular wall thickness was measured using the cut off method from SPECT images obtained at 5.6 mm intervals from the base and middle of left ventricle: short-axis image for the base and middle of left ventricle and vertical and horizontal long-axis images for the apical region. Wall thickness was defined from the number of pixel above the cut off level. Results of fundamental studies disclosed that it is impossible to evaluate the thickness of less than 10 mm by Tl-201 myocardial SPECT but possible to discriminate wall thickness of 10 mm, 15 mm, and 20 mm by Tl-201 myocardial SPECT. Echocardiographic results supported the validity of WTM, showing a good linear correlation (r = 0.96) between two methods on measuring wall thickness of left ventricle. We conclude that the WTM applied in this report may be useful for objective and quantitative estimation of myocardial hypertrophy. (author)

Automated quantitative coronary computed tomography correlates of myocardial ischaemia on gated myocardial perfusion SPECT

International Nuclear Information System (INIS)

Graaf, Michiel A. de; Boogers, Mark J.; Veltman, Caroline E.; El-Naggar, Heba M.; Bax, Jeroen J.; Delgado, Victoria; Broersen, Alexander; Kitslaar, Pieter H.; Dijkstra, Jouke; Kroft, Lucia J.; Younis, Imad Al; Reiber, Johan H.; Scholte, Arthur J.

2013-01-01

Automated software tools have permitted more comprehensive, robust and reproducible quantification of coronary stenosis, plaque burden and plaque location of coronary computed tomography angiography (CTA) data. The association between these quantitative CTA (QCT) parameters and the presence of myocardial ischaemia has not been explored. The aim of the present investigation was to evaluate the association between QCT parameters of coronary artery lesions and the presence of myocardial ischaemia on gated myocardial perfusion single-photon emission CT (SPECT). Included in the study were 40 patients (mean age 58.2 ± 10.9 years, 27 men) with known or suspected coronary artery disease (CAD) who had undergone multidetector row CTA and gated myocardial perfusion SPECT within 6 months. From the CTA datasets, vessel-based and lesion-based visual analyses were performed. Consecutively, lesion-based QCT was performed to assess plaque length, plaque burden, percentage lumen area stenosis and remodelling index. Subsequently, the presence of myocardial ischaemia was assessed using the summed difference score (SDS ≥2) on gated myocardial perfusion SPECT. Myocardial ischaemia was seen in 25 patients (62.5 %) in 37 vascular territories. Quantitatively assessed significant stenosis and quantitatively assessed lesion length were independently associated with myocardial ischaemia (OR 7.72, 95 % CI 2.41-24.7, p 2 = 20.7) and lesion length (χ 2 = 26.0) to the clinical variables and the visual assessment (χ 2 = 5.9) had incremental value in the association with myocardial ischaemia. Coronary lesion length and quantitatively assessed significant stenosis were independently associated with myocardial ischaemia. Both quantitative parameters have incremental value over baseline variables and visually assessed significant stenosis. Potentially, QCT can refine assessment of CAD, which may be of potential use for identification of patients with myocardial ischaemia. (orig.)

Myocardial images in nonacute coronary and noncoronary heart diseases

International Nuclear Information System (INIS)

Poe, N.D.; Eber, L.M.; Norman, A.S.; Selin, C.E.; Terao, E.N.

1977-01-01

To determine the variables that might affect interpretability of myocardial perfusion images in patients with acute myocardial infarctions, images obtained following intravenous administration of potassium-43 or cesium-129 were evaluated in 68 patients with nonacute coronary or noncoronary heart diseases, who were undergoing cardiac catheterization. Severe coronary arterial disease usually produces no distinctive perfusion defects in the resting state. Remote infarcts likewise tend to remain undetectable unless accompanied by wall-motion disturbances that can be detected by ventriculography. Left ventricular hypertrophy or cardiac dilatation can produce perfusion patterns indistinguishable from the ischemic defects of infarction. Right ventricular hypertrophy can cause image alterations that mimic infarcts in the left ventricle. In patients with acute myocardial infarction, sequential imaging studies with perfusion indicators should be of value in determining the effects of various therapeutic maneuvers on regional myocardial perfusion, but variations caused by conditions other than acute vascular occlusion limit the usefulness of perfusion imaging for diagnosing acute infarction. In suspected acute infarction, perfusion imaging will be used most effectively in conjunction with other imaging or nonimaging procedures that show the presence of damaged or necrotic myocardium. The information derived from this study should be generally applicable to the interpretation of imaging results obtained with the newer indicators of myocardial perfusion now in use or under development

Myocardial contusion in patients with blunt chest trauma as evaluated by thallium 201 myocardial scintigraphy

International Nuclear Information System (INIS)

Bodin, L.; Rouby, J.J.; Viars, P.

1988-01-01

Fifty five patients suffering from blunt chest trauma were studied to assess the diagnosis of myocardial contusion using thallium 201 myocardial scintigraphy. Thirty-eight patients had consistent scintigraphic defects and were considered to have a myocardial contusion. All patients with scintigraphic defects had paroxysmal arrhythmias and/or ECG abnormalities. Of 38 patients, 32 had localized ST-T segment abnormalities; 29, ST-T segment abnormalities suggesting involvement of the same cardiac area as scintigraphic defects; 21, echocardiographic abnormalities. Sixteen patients had segmental hypokinesia involving the same cardiac area as the scintigraphic defects. Fifteen patients had clinical signs suggestive of myocardial contusion and scintigraphic defects. Almost 70 percent of patients with blunt chest trauma had scintigraphic defects related to areas of myocardial contusion. When thallium 201 myocardial scintigraphy directly showed myocardial lesion, two-dimensional echocardiography and standard ECG detected related functional consequences of cardiac trauma

Exercise induced ST elevation and residual myocardial ischemia in previous myocardial infarction

International Nuclear Information System (INIS)

Shimonagata, Tsuyoshi; Nishimura, Tsunehiko; Uehara, Toshiisa; Hayashida, Kohei; Saito, Muneyasu; Sumiyoshi, Tetsuya

1987-01-01

The purpose of this study was to evaluate the clinical significance of stress induced ST elevation on infarcted area in 65 patients with previous myocardial infarction (single vessel disease) who had stress thallium scan. Stress induced ST changes on infarcted area were compared with quantitative assessment of myocardial ischemia (thallium ischemic score; TIS) and extent of myocardial infarction (defect score; DS) derived from circumferential profile analysis. In patients with previous myocardial infarction in less than 3 month from the onset (n = 36), left ventricular ejection fraction (LVEF) and extent of abnormal LV wall motion were not significantly different between patients with stress induced ST elevation ( ≥ 2 mm, n = 26) and those with stress induced ST elevation ( < 2 mm, n = 10), while, in patients with previous myocardial infarction in more than 3 month (n = 29), patients with stress induced ST elevation ( ≥ 2 mm, n = 15) showed left ventricular dyskinesis more frequently than those with ST elevation ( < 2 mm, n = 14). In addition, the former showed significantly higher DS and significantly lower TIS than the latter. In patients with previous myocardial infarction in less than 3 month, patients with ST elevation ( ≥ 2 mm, n = 15) with prominent upright T wave (n = 15) had transient thallium defect in infarcted area in 73 % and they had significantly higher LVEF and TIS than those with ST elevation ( < 2 mm, n = 11). These results indicated that ST elevation in infarcted area reflect different significance according to the recovery of injured myocardium and stress induced ST elevation with prominent upright T wave in infarcted area reflect residual myocardial ischemia in less than 3 month from the onset of myocardial infarction. (author)

Acute myocardial infarct imaging with indium-111-labeled monoclonal antimyosin Fab

International Nuclear Information System (INIS)

Khaw, B.A.; Yasuda, T.; Gold, H.K.; Leinbach, R.C.; Johns, J.A.; Kanke, M.; Barlai-Kovach, M.; Strauss, H.W.; Haber, E.

1987-01-01

Indium-111 monoclonal antimyosin Fab scintigraphy was used to detect myocardial necrosis in 52 of 54 patients (96.3%) with acute myocardial infarction. Infarcts were visualized when coronary arteries were persistently occluded (n = 10), became patent after thrombolysis (n = 33), or became patent after spontaneous reperfusion (n = 7). Posteroinferolateral visualizations were obtained in two patients with clinical and enzymatic evidence of infarction but normal electrocardiograms. Of the two patients in whom no infarcts were visualized, one had an anterior myocardial infarct. This patient underwent successful thrombolytic therapy, with attendant minimization of creatine kinase release. The other patient had a small, nonreperfused inferior myocardial infarct. Five patients with a history of remote infarction and acute necrosis showed antimyosin uptake only in regions concordant with the acute episodes of infarction, and radiolabeled antimyosin Fab localized in neither old infarcts nor normal, noninfarcted myocardium. Antimyosin Fab scintigraphy, thus, appears to be a highly specific means of delineating necrotic myocardium, at least in this limited and selected group of patients

Myocardial infarction in the conscious dog: three dimensional mapping of infarct, collateral flow and region at risk

International Nuclear Information System (INIS)

Jugdutt, B.I.; Hutchins, G.M.; Bulkley, B.H.; Becker, L.C.

1979-01-01

Myocardial infarcts were examined in dogs to determine the spatial distribution of infarction in the region at risk and the relation between infarction and collateral blood flow. Permanent occlusion of the left circumflex (LC) coronary artery at a constant site was made in 27 conscious dogs that were sacrificed 2 days later. The anatomic region at risk was defined by postmortem coronary arteriography as the volume of the occluded LC coronary bed. The masses of the left ventricle (LV), infarct (I) and risk region (R) were calculated from planimetered areas of weighted bread-loaf sections of LV. Infarct size was directly related to the mass of the risk region (I = 0.53 R - 9.87; r = 0.97; p < 0.001). There was no infarction when R was less than about 20 g or 20% of the LV. The infarcts were mainly subendocardial and tapered from base to apex of the LV; 34% of the risk region became infarcted at the base compared with 22% at the apex. In all dogs, a significant rim of noninfarcted myocardium was identified at lateral aspects of the risk region, even at the endocardial surface. Using 9-μ radioactive microspheres, initial postocclusion flow at the margin of the infarct, but well within the risk region, was higher than at the center, and outer flows were higher than inner flows. Postocclusion flow was even higher in the noninfarcted rim within the risk region, but was still significantly less than flow to normal, nonrisk areas. Collateral flows throughout the risk region increased during the first hour after occlusion, and were even higher at 2 days.Epicardially and laterally within the anatomic risk region there is a substantial amount of tissue that does not infarct despite initally reduced blood flow

Sex-specific criteria for interpretation of thallium-201 myocardial uptake and washout studies

International Nuclear Information System (INIS)

Rabinovitch, M.; Suissa, S.; Elstein, J.

1986-01-01

A study was undertaken to determine the effect of gender on criteria for the quantitative analysis of exercise-redistribution 201 Tl myocardial scintigraphy. The studies of 26 normal females and 23 normal males were subjected to bilinear interpolative background subtraction and horizontal profile analysis. Significant sexual differences were found in both regional uptake ratios and washout rates. These differences primarily reflected a proportionately decreased anterior and upper septal uptake in females, and faster washout in females. Faster myocardial 201 Tl washout rates in females could not be clearly ascribed to either a physiological or artifactual explanation. It is concluded that since important differences exist between males and females in the detected pattern of 201 Tl myocardial uptake and washout, sex-specific criteria may enhance the predictive accuracy of exercise-redistribution 201 Tl myocardial scintigraphy

Myocardial ischemia in hypertrophic cardiomyopathy

International Nuclear Information System (INIS)

Lima Filho, Moyses de Oliveira; Figueiredo, Geraldo L.; Simoes, Marcus V.; Pyntia, Antonio O.; Marin Neto, Jose Antonio

2000-01-01

Myocardial ischemia in hypertrophic cardiomyopathy is multifactorial and explains the occurrence of angina, in about 50% of patients. The pathophysiology of myocardial ischemia may be explained by the increase of the ventricular mass and relative paucity of the coronary microcirculation; the elevated ventricular filling pressures and myocardial stiffness causing a compression of the coronary microvessels; the impaired coronary vasodilator flow reserve caused by anatomic and functional abnormalities; and the systolic compression of epicardial vessel (myocardial bridges). Myocardial ischemia must be investigated by perfusion scintigraphic methods since its presence influences the prognosis and has relevant clinical implications for management of patients. Patients with hypertrophic cardiomyopathy and documented myocardial ischemia usually need to undergo invasive coronary angiography to exclude the presence of concomitant atherosclerotic coronary disease. (author)

Relationship between availability of the collateral circulation and ischemic time for myocardial viability in patients with acute myocardial infarction. Assessment by technetium-99m tetrofosmin single photon emission computed tomography

International Nuclear Information System (INIS)

Kanamori, Norio; Kondo, Makoto; Fukuoka, Yoshitomo; Higuchi, Hirokazu; Kubota, Tomoyuki; Matsuoka, Ryota; Araki, Makoto; Tanio, Hitoshi; Doyama, Kiyoshi

2007-01-01

Myocardial accumulation before reperfusion therapy of a radioactive tracer in the completely occluded region, conceivably reflects the viability of myocytes and degree of collateral circulation. To confirm this, the present study examined the relationship in the title. Subjects were 33 patients (F 7, M 26; average age 65 y) of the first 1-branch acute myocardial infarction and of TIMI (thrombolysis in myocardial infarction trial) grade 0 who recovered to TIMI 3 within 12 hr after attack: 99m Tc-tetrofosmin, 740 MBq, was intravenously injected before reperfusion and just after which, SPECT imaging (TF-SPECT) was conducted with Toshiba E. CAM, and regional severity score index (RSSI) (0-3) was calculated. About 1 week later, to see the myocardial viability in the chronic phase, GITl (Glucose-Insulin- 201 Tl) (111 MBq) SPECT was performed 30 min after its injection to calculate RSSI as above, and the echocardiography with ALOKA Pro Sound SSD-4000 or SIEMENS Acuson SEQUOIA C256 was done to calculate the regional wall motion score index (RWMSI) (0-4). RWMSI was found significantly correlated with TF-RSSI, the group with the better collateral circulation (TF-RSSI, 1.9 or less) exhibited significantly lower GITl-RSSI and RWMSI, and correlation between the ischemic time and neither TF-RSSI, GITl-RSSI nor RWMSI was found. Thus under these conditions, the development of collateral vessels was found to have potential protective effects on myocardium independently on the ischemic time. (T.I.)

Comparison of single-dose and double-dose thallium-201 myocardial perfusion scintigraphy for the detection of coronary artery disease and prior myocardial infarction

International Nuclear Information System (INIS)

Blood, D.K.; McCarthy, D.M.; Sciacca, R.R.; Cannon, P.J.

1978-01-01

Thallium-201 myocardial perfusion scintigraphy was performed after exercise, 4 hours after exercise (redistribution) and after a separate rest injection in 87 patients undergoing coronary arteriography. Significant coronary lesions were present in 62 of the patients. Interpretation of the rest and redistribution scintiscans was the same in 69 patients, 45 of whom had coronary artery disease (CAD). In 16 of the 17 patients with CAD and differing interpretations, defects were present on redistribution scintiscans but not on rest scintiscans; 11 of these patients had evidence of prior transmural myocardial infarction and the other five had an occluded coronary artery supplying the region of the defect. Redistribution scintiscans were more sensitive than rest scintiscans for the detection of prior myocardial infarction (93% vs 54%; P < 0.01). The increased sensitivity was confined to the detection of prior inferior myocardial infarctions. In 36 of 38 patients with persistent perfusion defects on 4-hour redistribution scintiscans, either a prior infarction or an occluded coronary vessel was present. These data demonstrate that redistribution thallium-201 scintiscans may be substituted for conventional rest scintiscans, resulting in reduced cost and radiation exposure to the patients

Aid in the detection of myocardial perfusion abnormality utilizing SPECT atlas and images registration: preliminary results

International Nuclear Information System (INIS)

Padua, Rodrigo Donizete Santana de; Oliveira, Lucas Ferrari de; Marques, Paulo Mazzoncini de Azevedo; Groote, Jean-Jacques Georges Soares de; Castro, Adelson Antonio de; Ana, Lauro Wichert; Simoes, Marcus Vinicius

2008-01-01

To develop an atlas of myocardial perfusion scintigraphy and evaluating its applicability in computer-aided detection of myocardial perfusion defects in patients with ischemic heart disease. The atlas was created with rest-stress myocardial perfusion scintigraphic images of 20 patients of both genders with low probability of coronary artery disease and considered as normal by two experienced observers. Techniques of image registration and mathematical operations on images were utilized for obtaining template images depicting mean myocardial uptake and standard deviation for each gender and physiological condition. Myocardial perfusion scintigraphy images of one male and one female patient were aligned with the corresponding atlas template image, and voxels with myocardial uptake rates two standard deviations below the mean voxel value of the respective region in the atlas template image were highlighted on the tomographic sections and confirmed as perfusion defects by both observe. The present study demonstrated the creation of an atlas of myocardial perfusion scintigraphy with promising results of this tool as an aid in the detection of myocardial perfusion defects. However, further prospective validation with a more representative sample is recommended. (author)

Aid in the detection of myocardial perfusion abnormality utilizing SPECT atlas and images registration: preliminary results

Energy Technology Data Exchange (ETDEWEB)

Padua, Rodrigo Donizete Santana de [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Faculdade de Medicina. Div. de Cardiologia]. E-mail: rodrigo_dsp@hcrp.fmrp.usp.br; Oliveira, Lucas Ferrari de [Universidade Federal de Pelotas (UFPel), RS (Brazil). Inst. de Fisica e Matematica. Dept. de Tecnologia da Informacao; Marques, Paulo Mazzoncini de Azevedo [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Faculdade de Medicina. Centro de Ciencias das Imagens e Fisica Medica; Groote, Jean-Jacques Georges Soares de [Instituto de Ensino Superior COC, Ribeirao Preto, SP (Brazil). Lab. of Artifical Intelligence and Applications; Castro, Adelson Antonio de [Universidade de Sao Paulo (USP), Ribeirao Preto, SP, (Brazil). Faculdade de Medicina; Ana, Lauro Wichert [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Faculdade de Medicina. Centro de Ciencias das Imagens e Fisica Medica; Simoes, Marcus Vinicius [Universidade de Sao Paulo (USP), Ribeirao Preto, SP, (Brazil). Faculdade de Medicina. Divisao de Cardiologia

2008-11-15

To develop an atlas of myocardial perfusion scintigraphy and evaluating its applicability in computer-aided detection of myocardial perfusion defects in patients with ischemic heart disease. The atlas was created with rest-stress myocardial perfusion scintigraphic images of 20 patients of both genders with low probability of coronary artery disease and considered as normal by two experienced observers. Techniques of image registration and mathematical operations on images were utilized for obtaining template images depicting mean myocardial uptake and standard deviation for each gender and physiological condition. Myocardial perfusion scintigraphy images of one male and one female patient were aligned with the corresponding atlas template image, and voxels with myocardial uptake rates two standard deviations below the mean voxel value of the respective region in the atlas template image were highlighted on the tomographic sections and confirmed as perfusion defects by both observe. The present study demonstrated the creation of an atlas of myocardial perfusion scintigraphy with promising results of this tool as an aid in the detection of myocardial perfusion defects. However, further prospective validation with a more representative sample is recommended. (author)

Relationship between collateral circulation and myocardial viability of 18F-FDG PET/CT subtended by chronic total occluded coronary arteries.

Science.gov (United States)

Dong, Wei; Li, Jianan; Mi, Hongzhi; Song, Xiantao; Jiao, Jian; Li, Quan

2018-04-01

To analyze the relationship between the collateral flow of coronary chronic total occlusion (CTO) and myocardial viability detected by 18 F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) imaging. A prospective analysis of 104 patients diagnosed by coronary angiography. All patients underwent resting myocardial perfusion imaging and PET/CT within 1 week. The collateral circulation was graded with Rentrop classification as no or poor collateral circulation in 16 CTO vessels, moderate collateral circulation in 34 CTO vessels, and good collateral circulation in 69 CTO vessels. Myocardial viability was determined with myocardial perfusion imaging and PET. The patterns were interpreted as mismatch, match and normal perfusion and 18 F-FDG uptake. There was no significant correlation between the severity and extent of perfusion defect, myocardial viability and collateral circulation grade. The myocardial viability was normal in mild and moderate hypokinetic regions and decreased in severe hypokinetic and akinesis-dyskinesis regions. The presence of collateral circulation was a sensitive (89%) but not a specific (31%) sign of myocardial viability. In patients with CTO, collateral circulation does not seem to be an effective way for predicting myocardial viability. Further analysis of PET patterns of viable myocardium is needed to guide further revascularization and predict functional improvement and survival benefit.

Regional rates of myocardial fatty acid metabolism: comparison with coronary angiography and ventriculography.

Science.gov (United States)

Schad, N; Wagner, R K; Hallermeier, J; Daus, H J; Vattimo, A; Bertelli, P

1990-01-01

In 50 patients, 1 mCi 123I phenylpentadecanoic acid (IPPA) was injected at peak ergometric stress and 1500 frames were acquired (1 frame/s) with a high count rate gamma camera. Parametric images of rates of decrease and increase for different time intervals after stress were compared with coronary angiography and LV ventriculography, separately evaluating the 3 main coronary territories: 18/150 territories supplied by normal coronaries presented rather homogeneous regional clearing rates, whereas a gradual decrease in clearing rates towards the end of the territory (frequently with peripheral defects) was seen in all 87/150 territories with significant coronary narrowing. In local correspondence to clearing defects, initial IPPA accumulations could be observed with later onset of clearing between 10 and 25 min. 44/150 territories presented abnormal clearing rates, mostly with a patchy pattern, with normal coronary anatomy, but all except one had LV dysfunction and a clinical diagnosis of cardiomyopathy, diabetes mellitus or hypertensive disease. Twenty four of the 41 patients with CAD had, in correspondence to a prior myocardial infarction, minimum or missing metabolic activity frequently in circumscribed zones, partly separated by bridges of still viable tissue with preserved but reduced clearing rates.

Automated quantitative coronary computed tomography correlates of myocardial ischaemia on gated myocardial perfusion SPECT

Energy Technology Data Exchange (ETDEWEB)

Graaf, Michiel A. de; Boogers, Mark J.; Veltman, Caroline E. [Leiden University Medical Center, Department of Cardiology, Leiden (Netherlands); The Interuniversity Cardiology Institute of The Netherlands, Utrecht (Netherlands); El-Naggar, Heba M.; Bax, Jeroen J.; Delgado, Victoria [Leiden University Medical Center, Department of Cardiology, Leiden (Netherlands); Broersen, Alexander; Kitslaar, Pieter H.; Dijkstra, Jouke [Leiden University Medical Center, Department of Radiology, Division of Image Processing, Leiden (Netherlands); Kroft, Lucia J. [Leiden University Medical Center, Department of Radiology, Leiden (Netherlands); Younis, Imad Al [Leiden University Medical Center, Department of Nuclear Medicine, Leiden (Netherlands); Reiber, Johan H. [Leiden University Medical Center, Department of Radiology, Division of Image Processing, Leiden (Netherlands); Medis medical imaging systems B.V., Leiden (Netherlands); Scholte, Arthur J. [Leiden University Medical Center, Department of Cardiology, Leiden (Netherlands)

2013-08-15

Automated software tools have permitted more comprehensive, robust and reproducible quantification of coronary stenosis, plaque burden and plaque location of coronary computed tomography angiography (CTA) data. The association between these quantitative CTA (QCT) parameters and the presence of myocardial ischaemia has not been explored. The aim of the present investigation was to evaluate the association between QCT parameters of coronary artery lesions and the presence of myocardial ischaemia on gated myocardial perfusion single-photon emission CT (SPECT). Included in the study were 40 patients (mean age 58.2 {+-} 10.9 years, 27 men) with known or suspected coronary artery disease (CAD) who had undergone multidetector row CTA and gated myocardial perfusion SPECT within 6 months. From the CTA datasets, vessel-based and lesion-based visual analyses were performed. Consecutively, lesion-based QCT was performed to assess plaque length, plaque burden, percentage lumen area stenosis and remodelling index. Subsequently, the presence of myocardial ischaemia was assessed using the summed difference score (SDS {>=}2) on gated myocardial perfusion SPECT. Myocardial ischaemia was seen in 25 patients (62.5 %) in 37 vascular territories. Quantitatively assessed significant stenosis and quantitatively assessed lesion length were independently associated with myocardial ischaemia (OR 7.72, 95 % CI 2.41-24.7, p < 0.001, and OR 1.07, 95 % CI 1.00-1.45, p = 0.032, respectively) after correcting for clinical variables and visually assessed significant stenosis. The addition of quantitatively assessed significant stenosis ({chi} {sup 2} = 20.7) and lesion length ({chi} {sup 2} = 26.0) to the clinical variables and the visual assessment ({chi} {sup 2} = 5.9) had incremental value in the association with myocardial ischaemia. Coronary lesion length and quantitatively assessed significant stenosis were independently associated with myocardial ischaemia. Both quantitative parameters have

Myocardial viability assessed by Tl-201 SPECT. Redistribution versus reinjection

International Nuclear Information System (INIS)

Chalela, William Azem; Pimentel, Flavio Ferrarini de Oliveira; Uchida, Augusto Hiroshi; Bottega, Augusto; Ramires, Jose Antonio Franchine; Izaki, Marisa; Moraes, Aguinaldo Pereira; Soares Junior, Jose; Giorgi, Maria C. Pinto; Moffa, Paulo Jorge; Bellotti, Giovanni; Giovanni Guido Cerri; Meneghetti, Jose Claudio

1994-01-01

The purpose of this study was to verify if a third series of images acquired by reinjection thallium-201, 24 h after conventional myocardial perfusion with the radioisotope, improves the identification of myocardial viability segments. The methods: we studied 30 patients, mean age 57.7 ±9.4 years, with old myocardial infarction using thallium (Tl)-201 SPECT, and we obtained three series of images (stress, redistribution after 4 h and reinjection after 24 h. Cardiac images were divided in 5 segments (apical, lateral, anterior, septal and inferior) and each one received a value by a score system according to the Tl-201 myocardial uptake (0=normal uptake; 1=mild hypoperfusion; 2=moderate hypoperfusion; 3=severe hypoperfusion or no myocardial uptake). We considered viable myocardium when the uptake of Tl-201 in the segment related to te myocardial infarction increases at least 1 point in two different axis of Tl-201 SPECT. The results: seven (23,3%) patients demonstrated increase of Tl-201 uptake only at reinjection images, showing a high efficacy of the method. Nine (30%) patients showed persistent hypoperfusion at all series of images suggesting only fibrosis in the are related to the infarction. Fourteen (46,7%) patients showed increase of Tl-201 concentration at redistribution images; among these patients, six showed improvement of myocardial uptake at reinjection. This condition was interpreted as regional chronic ischemic process: hibernating myocardium. The conclusion was that Tl-201 hypoperfusion at redistribution images without significant changes in relation to the stress images do not represent fibrosis at all. The reinjection technic was better than conventional redistribution in the detection of viable myocardium. This data allows a better therapeutic orientation. (author)

Influence of angiographic collateral circulation on myocardial perfusion in patients with chronic total occlusion of a single coronary artery and no prior myocardial infarction.

Science.gov (United States)

Aboul-Enein, Fatma; Kar, Saibal; Hayes, Sean W; Sciammarella, Maria; Abidov, Aiden; Makkar, Raj; Friedman, John D; Eigler, Neal; Berman, Daniel S

2004-06-01

The functional role of various angiographic grades for coronary collaterals remains controversial. The aim of this study was to assess the influence of the Rentrop angiographic grading of coronary collaterals on myocardial perfusion in patients with single-vessel chronic total occlusion (CTO) and no prior myocardial infarction (MI). The study included 56 patients with single-vessel CTO and no prior MI who underwent rest-stress myocardial perfusion SPECT and coronary angiography within 6 mo. All patients had angiographic evidence of coronary collaterals. Patients were divided according to the Rentrop classification: Group I had grade 1 or 2 (n = 25) and group II had grade 3 collaterals (n = 31). Group I had a higher frequency of resting regional wall motion abnormalities on left ventriculography (52.6% vs. 19.2% [P = 0.019]). The mean perfusion scores of the overall population showed severe and extensive stress perfusion defects (summed stress score of 14.1 +/- 7.1 and summed difference score of 12.9 +/- 6.9) but minimal resting perfusion defects (summed rest score of 1.0 +/- 2.7). No perfusion scores differed between the 2 groups. The perfusion findings suggested that chronic stunning rather than hibernation is the principal cause of regional wall motion abnormalities in these patients. In the setting of single-vessel CTO and no prior MI, coronary collaterals appear to protect against resting perfusion defects. Excellent angiographic collaterals may prevent resting regional wall motion abnormalities but do not appear to protect against stress-induced perfusion defects.

Thallium-201 myocardial imaging in acute-myocardial infarction

International Nuclear Information System (INIS)

Wackers, F.J.Th.; Lie, K.I.; Sokole, E.B.; Wellens, H.J.J.; Samson, G.; Schoot, J.B. van der

1980-01-01

Thallium-201 scintigraphy has proven to be an early and highly sensitive technique to detect myocardial perfusion abnormalities in patients with acute myocardial infarction. During the early phase of acute myocardial infarction, patients may be hemodynamically and electrically unstable. Therefore, scintigraphy is performed preferably at the bed side in the Coronary Care Unit using a mobile gamma camera. Additionally, in order to shorten imaging time in these often critically ill patients, the authors recommend injecting no less than 2 mCi of 201 Tl. Using this dosage, the imaging time per view will be approximately five minutes. Routinely, three views are taken: the first view is a supine 45 0 left-anterior-oblique view, followed by a supine anterior view and finally a left-lateral view, the latter with the patient turned on the right side. (Auth.)

Evaluation of left ventricular function in patient with old myocardial infarction by 201-thallium myocardial scintigraphy

Energy Technology Data Exchange (ETDEWEB)

Takahashi, Kanji; Shimohara, Yasuaki; Ito, Misao; Okada, Keisei [Kure Kyosai Hospital, Hiroshima (Japan); Kodama, Kazunori

1984-08-01

Correlation between the ratio of myocardial defect calculated by 201-thallium myocardial scintigraphy and the left ventricular ejection fraction (LVEF) obtained by gated blood pool scintigraphy and the maximum level of creatine phosphokinase (CPK) was studied in 70 patients with old myocardial infarction. There was a significant correlation between the defect ratio and the LVEF or CPK level in patients with anterior or septal myocardial infarction. In all patients with inferior myocardial infarction in whom no defect was seen, the LVEF was more than 40%. However, no distinct correlation between the defect ratio and the LVEF or CPK level was obtained in cases of inferior myocardial infarction.

Evaluation of carbohydrate cardiac metabolism by the 18FDG and positron emission tomography in the myocardial infarction with healthy coronaries

International Nuclear Information System (INIS)

Agostini, D.; Quennelle, F.; Babatasi, G.; Grollier, G.; Potier, J.C.; Bouvard, G.

1997-01-01

The aim of this study was to evaluate the regional myocardial metabolism of glucose (RMMG) by positron emission tomography (PET) with fluoro-de-oxy-glucose ( 18 FDG) in patients having myocardial infarction with healthy coronaries (MIHC). Four patients (4M, age: 41 ± 12 years) have presented: MI with a coronarography showing no significant lesions on the epicardial arteries, an irreversible anterior hypo-perfusion, moderated at 201 Tl scintigraphy and an isotopic FEVG 18 FDG. The dynamical images allow measuring RMMG and the static image to define the regions of interest on ventricular transaxial cross sections. A myocardial region embodying the totality of VG, including the septal, anterior and lateral regions and an intracavitary region are handy delimited. A model with 3 compartments is applied to the time-activity curves measured in the VG (input function) and in the myocardium (Patlak's method) and allows measuring the RMMG. The mean value of RMMG, measured along the VG, is significantly diminished as compared with that measured in healthy subjects. In conclusion, the PET based on 18 FDG shows that the myocardial carbohydrate metabolism is altered in patients afflicted with MIHC

Dipyridamole-thallium-201 tomography documenting improved myocardial perfusion with therapy in Kawasaki disease

International Nuclear Information System (INIS)

Nienaber, C.A.; Spielmann, R.P.; Hausdorf, G.

1988-01-01

Thallium-201 tomographic perfusion studies after pharmacologic vasodilation were performed in seven children (aged 2 years 8 months to 8 years 7 months), 3 to 20 months after the acute stage of the disease. In all patients coronary aneurysms were seen on cross-sectional echocardiograms. The scintigrams of six children showed no significant regional reduction of myocardial thallium-201 uptake. These children had remained asymptomatic in the follow-up period after the acute inflammatory stage of Kawasaki disease. Persistent and transient thallium defects were present in one child with acute posterolateral myocardial infarction; obstruction of two coronary vessels supplying the defect zones was confirmed by contrast angiography. After 8 months of treatment a follow-up nuclear scan showed marked reduction in the size of the defect and almost complete abolishment of the ischemic reaction. Thus tomographic thallium-201 perfusion scintigraphy in conjunction with vasodilation stress is useful to assess myocardial perfusion in children with Kawasaki disease and demonstrates marked improvement in regional perfusion after adequate medical therapy

Assessment of myocardial fatty acid metabolism in patients with angina pectoris and diabetes mellitus using 123I-BMIPP myocardial scintigraphy

International Nuclear Information System (INIS)

Ito, Kazuki; Tanabe, Takuji; Yuba, Tatsuya; Doue, Tomoki; Adachi, Yoshihiko; Katoh, Shuuji; Sugihara, Hiroki; Azuma, Akihiro; Nakagawa, Masao

2001-01-01

We studied the effect of myocardial ischemia and diabetes mellitus (DM) on the myocardial fatty acid metabolism using 123 I-BMIPP myocardial scintigraphy. We performed 123 I-BMIPP myocardial scintigraphy in 50 patients with myocardial ischemia and without DM (AP), in 30 patients with myocardial ischemia and DM (AP+DM), 12 patients with DM and without myocardial ischemia (DM), and in 10 normal subjects (N). Myocardial uptake rate of 123 I-BMIPP was obtained using the time activity curve. Myocardial washout rate of 123 I-BMIPP was calculated using the polar images of early and delayed SPECT images. Myocardial uptake rate of 123 I-BMIPP (%) were AP: 4.9±0.6, AP+DM: 5.5±0.5, DM 5.7±0.5 and N: 5.0±0.4. 123 I-BMIPP myocardial uptake rate was increased in AP+DM and DM. 123 I-BMIPP myocardial washout rate (%) were AP: 30.2±4.3, AP+DM: 24.5±3.9, DM: 16.1±2.8 and N: 19.4±3.2. 123 I-BMIPP myocardial washout rate was increased in AP and AP+DM. 123 I-BMIPP myocardial washout rate was increased particularly in patients with multi-vessels disease. 123 I-BMIPP myocardial washout rate was decreased in DM. The present study suggested that diabetes mellitus increased myocardial fatty acid uptake and decreased myocardial fatty acid washout, and that myocardial ischemia increased myocardial fatty acid washout. (author)

Effects of dipyridamole and aminophylline on hemodynamics, regional myocardial blood flow and thallium-201 washout in the setting of a critical coronary stenosis

International Nuclear Information System (INIS)

Granato, J.E.; Watson, D.D.; Belardinelli, L.; Cannon, J.M.; Beller, G.A.

1990-01-01

Experiments were performed to characterize the interaction of intravenous dipyridamole and aminophylline on thallium-201 transport kinetics, regional myocardial blood flow and systemic hemodynamics in the presence of a critical coronary artery stenosis. In 12 dogs with a critical left anterior descending coronary artery stenosis, arterial pressure decreased from a mean value (+/- SEM) of 107 +/- 6 to 94 +/- 3 mm Hg and distal left anterior descending artery pressure decreased from 70 +/- 7 to 55 +/- 4 mm Hg after intravenous administration of dipyridamole. In the left anterior descending perfusion zone, the endocardial/epicardial flow ratio decreased from 0.70 to 0.36 and the intrinsic thallium washout rate was significantly prolonged. Intravenous aminophylline reversed the dipyridamole-induced systemic hypotension and transmural coronary steal and restored the thallium washout rate to baseline values. In six other dogs, aminophylline alone resulted in no alterations in systemic and coronary hemodynamics or regional myocardial blood flow. As expected, dipyridamole-induced vasodilation and coronary steal were prevented by aminophylline pretreatment. These data show that in a canine model of partial coronary stenosis, systemic hypotension, adverse regional flow effects and prolonged thallium-201 washout consequent to intravenously administered dipyridamole are promptly reversed by intravenous aminophylline administration. Aminophylline alone had no significant hemodynamic and coronary flow effects. This study provides further insight into the altered thallium kinetics occurring as a consequence of dipyridamole-induced vasodilation and suggests that the prompt reversal of symptoms and signs of ischemia with aminophylline in patients receiving intravenous dipyridamole for clinical imaging studies probably reflects the reversal of transmural coronary steal

Clinical evaluation of sup 123 I-BMIPP myocardial scintigraphy in patients with hypertrophic cardiomyopathy

Energy Technology Data Exchange (ETDEWEB)

Ohtsuki, Katsuichi; Sugihara, Hiroki; Umamoto, Ikuo (Kyoto Prefectural Univ. of Medicine (Japan)) (and others)

1992-02-01

{sup 123}I-{beta}-methyl-p-iodophenylpentadecanoic acid ({sup 123}I-BMIPP) myocardial scintigraphy was performed in 13 patients with hypertrophic cardiomyopathy and compared with {sup 201}Tl myocardial scintigraphy performed within 3 months for evaluating the clinical significance of {sup 123}I-BMIPP myocardial scintigraphy. SPECT images were divided into 13 segments and segmental images were visually scored on a 4 (increased tracer uptake) to 0 (severely decreased tracer uptake) scale according to the tracer uptake. In comparison of {sup 123}I-BMIPP early images and {sup 201}Tl perfusion images, mismatches were seen in about 70% of all segments. The number of segments demonstrating lower myocardial uptake of {sup 123}I-BMIPP was larger than that of {sup 201}Tl. In hypertrophic regions, the tracer uptake of {sup 123}I-BMIPP early images was significantly lower than that of {sup 201}Tl images and the lower uptake of {sup 123}I-BMIPP delayed images was more marked. In non-hypertrophic regions, no significant difference was seen between the tracer uptakes of {sup 123}I-BMIPP early images and {sup 201}Tl images but the tracer uptake of {sup 123}I-BMIPP delayed images was significantly lower than that of {sup 201}Tl images. The mismatch between the tracer uptakes of {sup 123}I-BMIPP images and {sup 201}Tl images was thought to be a reflection of disordered myocardial fatty acid metabolism. 'Washout', the difference between the tracer uptakes of {sup 123}I-BMIPP early images and delayed images was also thought to be a reflection of disordered myocardial fatty acid metabolism. These results suggest that {sup 123}I-BMIPP is a promising radiopharmaceutical for evaluating disordered myocardial fatty acid metabolism in patients with HCM. (author).

Effectiveness of selective intracoronary thrombolysis in acute myocardial infarction

Energy Technology Data Exchange (ETDEWEB)

Yamaguchi, Hiroshi; Nosaka, Hideyuki; Saitoh, Taroh

1984-10-01

Protective effects of percutaneous transluminal coronary recanalization (PTCR) on the myocardium were investigated by creatine phosphokinase levels, regional left ventricular wall motion in chronic stage and /sup 201/Tl myocardial single photon emission computed tomography. Recanalization of the occlusive coronary artery at the early stage of myocardial infarction was effective for the protection of the myocardium and heart functions. This effect depended largely on the degree of occlusion at the time of the first imaging, the final degree of occlusion after recanalization, and the time required for the recanalization. Cases in which percutaneous transluminal coronary angiography was performed following PTCR are also presented and examined. (Namekawa, K.).

Effectiveness of selective intracoronary thrombolysis in acute myocardial infarction

International Nuclear Information System (INIS)

Yamaguchi, Hiroshi; Nosaka, Hideyuki; Saitoh, Taroh

1984-01-01

Protective effects of percutaneous transluminal coronary recanalization (PTCR) on the myocardium were investigated by creatine phospho kinase levels, regional left ventricular wall motion in chronic stage and 201 Tl myocardial single photon emission computed tomography. Recanalization of the occlusive coronary artery at the early stage of myocardial infarction was effective for the protection of the myocardium and heart functions. This effect depended largely on the degree of occlusion at the time of the first imaging, the final degree of occlusion after recanalization, and the time required for the recanalization. Cases in which percutaneous transluminal coronary angiography was performed following PTCR are also presented and examined. (Namekawa, K.)

Poisson-like shape and shoulder structure of hadron multiplicity distributions in e+e- annihilation at Z0 energy region

International Nuclear Information System (INIS)

Xie Yigang; Chai Yong

1994-01-01

The charged multiplicity distributions of hadron final states in the e + e - annihilation at the 91.2 GeV Z 0 energy region are fitted with Poisson shape in different rapidity windows for double and single hemisphere. The multiplicities which are in Poisson-like shapes can be got according to the parameter /D and fitting qualities are compared with the results derived from the relevant theoretical models. The relationship between the Poisson-like shape and KNO scaling is discussed. The connection between the parameters expressing the deviation from the Poisson shape and non-independent particle emission and multiplicity correlation strength is analyzed. The 'shoulder structure' is observed in the central rapidity region and analyzed with multi-jets by using the JADE jet analysis algorithm

Myocardial scintigraphy with thallium-201

Energy Technology Data Exchange (ETDEWEB)

Lichte, H [Zentralkrankenhaus Gauting (Germany, F.R.). Nuklearmedizinische Abt.

1977-04-01

Myocardial scintigraphy with /sup 201/thallium is a non-invasive method for detection of myocardial infarction and coronary heart disease. Redistribution-analysis as a sequential-scintigraphy of an exercise-scan permits to distinguish between myocardial scars and coronary vessel disease.

Physics at low spin in the mass 160 region: the search for tetrahedral shapes

International Nuclear Information System (INIS)

Bark, R.A.; Sharpey-Schafer, J.F.; Maliage, S.M.; Madiba, T.E.; Komati, F.S.; Lawrie, E.A.; Lawrie, J.J.; Lindasy, R.; Maine, P.; Mullins, S.M.; Murray, S.H.T.; Ncapayi, N.J.; Ramashidza, T.M.; Smit, F.D.; Vymers, P.

2010-01-01

The low-lying, odd-spin negative parity bands in the mass 160 region have been identified as candidates for the rotation of a tetrahedral shape, as they have very weak in-band E2 transitions. We report the observation of such bands in 160 Yb and 154 Gd. They are crossed by 2 quasiparticle bands which allow band mixing calculations to be carried out to derive relative quadrupole moments. However, those studied are not consistent with zero, as required for tetrahedral shape. The aligned angular momenta of the bands suggest an octupole vibrational assignment.

Assessment of myocardial viability using multidetector computed tomography in patients with reperfused acute myocardial infarction

International Nuclear Information System (INIS)

Kim, T.; Choi, B.J.; Kang, D.K.; Sun, J.S.

2012-01-01

Aim: To assess the prognostic value of 64-section multidetector computed tomography (MDCT) to predict follow-up myocardial dysfunction and functional recovery after reperfusion therapy in patients with acute myocardial infarction (MI) as defined by echocardiography. Materials and methods: After reperfusion therapy for acute MI, 71 patients underwent two-phase contrast-enhanced MDCT and follow-up echocardiography. MDCT findings were compared with echocardiographic findings using kappa statistics. The areas under the receiver operating characteristic curves (AUCs) and the odds ratios (ORs) of early perfusion defects (EPD), delayed enhancement (DE), and residual perfusion defects (RPD) for predicting follow-up myocardial dysfunction and functional recovery were calculated on a segmental basis. Results: The presence of transmural EPD (EPD TM ) or RPD showed good agreement (k = 0.611 and 0.658, respectively) with follow-up myocardial dysfunction, while subendocardial EPD (EPD sub ) or subendocardial DE (DE sub ) showed fair agreement with follow-up myocardial dysfunction (k = 0.235 and 0.234, respectively). The AUC of RPD (0.796) was superior (p TM (0.761) and DE TM (0.771). The presence of EPD TM , DE TM , and RPD were significant, independent positive predictors of follow-up myocardial dysfunction (OR = 6.4, 1.9, and 9.8, respectively). EPD TM was a significant, independent negative predictor of myocardial functional recovery (OR = 0.13). Conclusion: Abnormal myocardial attenuation on two-phase MDCT after reperfusion therapy may provide promising information regarding myocardial viability in patients with acute MI.

Early spontaneous intermittent myocardial reperfusion during acute myocardial infarction is associated with augmented thrombogenic activity and less myocardial damage

NARCIS (Netherlands)

Haider, A.W.; Andreotti, F.; Hackett, D.R.; Tousoulis, D.; Kluft, C.; Maseri, A.; Davies, G.J.

1995-01-01

Objectives. This study investigated the influence of early spontaneous intermittent reperfusion on the extent of myocardial damage and its relation to endogenous hemostatic activity, Background. In the early phase of acute myocardial infarction coronary occlusion is often intermittent, even before

Myocardial adrenergic nerve activity in valvular diseases assessed by iodine-123-metaiodobenzylguanidine myocardial scintigraphy

International Nuclear Information System (INIS)

Imamura, Yoshihiro; Fukuyama, Takaya

1997-01-01

Iodine-123-metaiodobenzylguanidine (MIBG) imaging was used to assess myocardial adrenergic nerve activity in patients with heart failure. MIBG planar images were obtained in 94 patients. The uptake of MIBG, calculated as the heart-to-mediastinum activity ratio in the immediate image (15 min), showed a significant decrease only in patients with severe heart failure due to cardiomyopathy, but was not changed in those with valvular diseases. Storage and release of MIBG, calculated as the percentage myocardial MIBG washout from 15 min to 4 hours after isotope injection, was substantially accelerated in both patients with cardiomyopathy and valvular diseases in proportion to the severity of heart failure. These data suggest that, in severe heart failure associated with cardiomyopathy, norepinephrine uptake is reduced. Also, myocardial adrenergic nerve activity is accelerated in proportion to the severity of heart failure independent of the underlying cause. MIBG images were analyzed in 20 patients with mitral stenosis with the same methods to clarify whether myocardial adrenergic nerve activity is different in patients with heart failure without left ventricular volume or pressure overload. Myocardial uptake of MIBG did not show any significant difference. The percentage myocardial MIBG washout was increased in patients with severe heart failure. The closest correlation was between myocardial washout and cardiac output. In heart failure due to mitral stenosis, myocardial adrenergic nerve activity is intensified. Decrease in cardiac output associated with mitral stenosis acts as a potent stimulus for this intensification. (author)

Pulse shape of the self quenching streamer counter in the coexistence region

International Nuclear Information System (INIS)

Chen Hongfang; Han Jiaxiang; Li Cheng; Xu Zizong

1996-01-01

The pulse shape of the electrical signal out of the counter operating in the self-quenching streamer (SQS) mode is obtained and the time correlation between the primary avalanche and the SQS avalanche is measured and studied. The results yield more information in the coexistence region about the time jitters in the process of the SQS avalanche than that shown in our last paper. (orig.)

Myocardial Hemorrhage After Acute Reperfused ST-Segment–Elevation Myocardial Infarction

Science.gov (United States)

Carrick, David; Haig, Caroline; Ahmed, Nadeem; McEntegart, Margaret; Petrie, Mark C.; Eteiba, Hany; Hood, Stuart; Watkins, Stuart; Lindsay, M. Mitchell; Davie, Andrew; Mahrous, Ahmed; Mordi, Ify; Rauhalammi, Samuli; Sattar, Naveed; Welsh, Paul; Radjenovic, Aleksandra; Ford, Ian; Oldroyd, Keith G.

2016-01-01

Background— The success of coronary reperfusion therapy in ST-segment–elevation myocardial infarction (MI) is commonly limited by failure to restore microvascular perfusion. Methods and Results— We performed a prospective cohort study in patients with reperfused ST-segment–elevation MI who underwent cardiac magnetic resonance 2 days (n=286) and 6 months (n=228) post MI. A serial imaging time-course study was also performed (n=30 participants; 4 cardiac magnetic resonance scans): 4 to 12 hours, 2 days, 10 days, and 7 months post reperfusion. Myocardial hemorrhage was taken to represent a hypointense infarct core with a T2* value of hemorrhage 2 days post MI was associated with clinical characteristics indicative of MI severity and inflammation. Myocardial hemorrhage was a multivariable associate of adverse remodeling (odds ratio [95% confidence interval]: 2.64 [1.07–6.49]; P=0.035). Ten (4%) patients had a cardiovascular cause of death or experienced a heart failure event post discharge, and myocardial hemorrhage, but not microvascular obstruction, was associated with this composite adverse outcome (hazard ratio, 5.89; 95% confidence interval, 1.25–27.74; P=0.025), including after adjustment for baseline left ventricular end-diastolic volume. In the serial imaging time-course study, myocardial hemorrhage occurred in 7 (23%), 13 (43%), 11 (33%), and 4 (13%) patients 4 to 12 hours, 2 days, 10 days, and 7 months post reperfusion. The amount of hemorrhage (median [interquartile range], 7.0 [4.9–7.5]; % left ventricular mass) peaked on day 2 (Phemorrhage and microvascular obstruction follow distinct time courses post ST-segment–elevation MI. Myocardial hemorrhage was more closely associated with adverse outcomes than microvascular obstruction. Clinical Trial Registration— URL: http://www.clinicaltrials.gov. Unique identifier: NCT02072850. PMID:26763281

The development of radioiodinated fatty acids for myocardial imaging

International Nuclear Information System (INIS)

Knapp, F.F. Jr.

1993-01-01

Since free fatty acids are the principal energy source for the normally oxygenated myocardium, the use of iodine-123-labeled fatty acid analogues is an attractive approach for myocardial imaging. Interest in the use of these substances results from divergent fatty acid metabolic pathways in ischemic (triglyceride storage) versus normoxic tissue (β-oxidative clearance), following flow-dependent delivery. Iodine-123-labeled fatty acids may offer a unique opportunity to identity myocardial viability using single photon emission tomography. The development of structurally-modified fatty acids became of interest because of the relatively long acquisition periods required for SPECT. The significant time required by early generation single- or dual-head SPECT systems for data acquisition requires minimal redistribution during the acquisition period to ensure accurate evaluation of the regional fatty acid distribution pattern after re-construction. Research has focussed on the evaluation of structural modifications which can be introduced into the fatty acid chain which would inhibit the subsequent β-oxidative catabolism which normally results in rapid myocardial clearance. Introduction of a methyl group in position-3 of the fatty acid carbon chain has been shown to significantly delay myocardial clearance and iodine-123-labeled 15-(p-iodophenyl)-3- R,S-methylpentadecanoic acid (BMIPP) is a new tracer based on this strategy

Quantitative evaluation of renal dynamic scan with 99mTc-MAG3 assessment of interoposterior myocardial infarction using ECG gated SPECT with 99mTc-MIBI

International Nuclear Information System (INIS)

Cho, Keiichi; Kumita, Shinichiro; Mizumura, Sunao

1997-01-01

Simultaneous assessment of regional myocardial perfusion and local contraction ability of interoposterior myocardial infarction was examined by ECG gated SPECT. In thirteen cases of acute interoposterior myocardial infarction, the above-mentioned data were obtained by 180deg data acquisition method using L-shaped 2 detecting element type gamma camera. Mean and standard deviation of %Uptake and wall thickening (WT) in inferior wall were as follows: Infarction case; 57±9.2%/23±11.3%, normal case; 71±8.2%/61±10.2%. The significant depression (p<0.01/p<0.001) of both data were found in the infarction case. The both data in posterior wall were as follows: Infarction case; 55±10.7%/16±8.9%, normal case; 64±9.7%/41±15.0%. The significant depression (p<0.05/p<0.001) were also found in the infarction case. In both inferior wall and posterior wall, the AUC of ROC curve of WT was greater than that of %Uptake, and diagnostic ability of this method was favorable. The best sensitivity/specificity rate and the threshold were as follows: %Uptake of inferior wall 77/65, -0.5SD, WT of inferior wall 100/100, -2SD, %Uptake of posterior wall 62/82, -1SD, WT of posterior wall 85/88, -4SD. Accordingly, in diagnosis of interoposterior myocardial infarction, assessment of focus cardiac function, for example WT, is necessary as well as %Uptake. (K.H.)

Assessment of maximal myocardial perfusion by ECG-triggered digital subtraction angiography

Energy Technology Data Exchange (ETDEWEB)

Pijls, N.H.J.; Uijen, G.J.H.; Werf, T. van der (Katholieke Univ. Nijmegen (Netherlands). Cardiology Dept.)

1991-01-01

Early studies about calculation of coronary blood flow by analysis of contrast agent passage on the coronary arteriogram were reported more than 2 decades ago by Rutishauser et al. and Smith et al. Thereafter is was shown that visualization of contrast passage through the myocardium could be enhanced by ECG-triggered digital subtraction imaging and it was suggested that myocardial flow could be calculated by studying the temporal changes in contrast intensity in a myocardial region of interest (ROI) as a function of time: the time density curve (TDC). (orig./GDG).

Unexpected myocardial uptake on bone scintigraphy in an infant with Kawasaki disease

International Nuclear Information System (INIS)

Macdonald, W.B.G.; Troedson, R.G.

2003-01-01

Full text: A two-month-old female infant was admitted to hospital because of irritability and poor feeding over the preceding two weeks. There was no history of fever but serum inflammatory markers were elevated and a throat swab yielded a pure growth of Strep, pyogenes. There was no response to antibiotics. The nursing staff noted the infant disliked handling and skeletal pathology was suspected. A bone scan using Tc-99m hydroxymethylene diphosphonate (HDP) showed myocardial activity, with no evidence of abnormal skeletal activity. Subsequent echocardiography showed coronary artery ectasia, typical of Kawasaki disease, with papillary muscle dysfunction, indicating likely myocarditis. A diagnosis of myocarditis secondary to Kawasaki disease was made and the patient promptly improved following intravenous immunoglobulin therapy. Cardiac manifestations of Kawasaki disease included coronary artery aneurysms, myocardial infarction, regional perfusion abnormalities and myocarditis. Myocardial uptake of phosphate tracers is well known following myocardial infarction but there was no wall motion disturbance or ECG abnormality to suggest infarction in this patient and she was felt to have myocarditis. Myocardial uptake of phosphate tracers has not previously been reported in Kawasaki disease. Copyright (2003) The Australian and New Zealand Society of Nuclear Medicine Inc

Mortality rate in type 2 myocardial infarction

DEFF Research Database (Denmark)

Saaby, Lotte; Poulsen, Tina Svenstrup; Diederichsen, Axel Cosmus Pyndt

2014-01-01

myocardial infarction, hypercholesterolemia, high p-creatinine, and diabetes mellitus. The multivariable-adjusted hazard ratio for type 2 myocardial infarction was 2.0 (95% confidence interval, 1.3-3.0). With shock as the only exception, mortality was independent of the triggering conditions leading to type....../119) in those with type 2 myocardial infarction and 26% (92/360) in those with type 1 myocardial infarction (P high age, prior myocardial infarction, type 2...... 2 myocardial infarction. CONCLUSIONS: Mortality in patients with type 2 myocardial infarction is high, reaching approximately 50% after 2 years. Further descriptive and survival studies are needed to improve the scientific evidence on which treatment of type 2 myocardial infarction is based....

VO(2peak), myocardial hypertrophy, and myocardial blood flow in endurance-trained men.

Science.gov (United States)

Laaksonen, Marko S; Heinonen, Ilkka; Luotolahti, Matti; Knuuti, Juhani; Kalliokoski, Kari K

2014-08-01

Endurance training induces cardiovascular and metabolic adaptations, leading to enhanced endurance capacity and exercise performance. Previous human studies have shown contradictory results in functional myocardial vascular adaptations to exercise training, and we hypothesized that this may be related to different degrees of hypertrophy in the trained heart. We studied the interrelationships between peak aerobic power (V˙O2peak), myocardial blood flow (MBF) at rest and during adenosine-induced vasodilation, and parameters of myocardial hypertrophy in endurance-trained (ET, n = 31) and untrained (n = 17) subjects. MBF and myocardial hypertrophy were studied using positron emission tomography and echocardiography, respectively. Both V˙O2peak (P negatively with adenosine-stimulated MBF, but when LV mass was taken into account as a partial correlate, this correlation disappeared. The present results show that increased LV mass in ET subjects explains the reduced hyperemic myocardial perfusion in this subject population and suggests that excessive LV hypertrophy has negative effect on cardiac blood flow capacity.

Usefulness of 99mTc-methoxy-iso-butyl-isonitrile myocardial single photon emission computed tomography during infusion of low-dose dobutamine and nitroglycerin. Evaluation of myocardial viability

International Nuclear Information System (INIS)

Yagi, Hidenori

1995-01-01

This study evaluated myocardial viability with 99m Tc-methoxy-iso-butyl-isonitrile (MIBI) single photon emission computed tomography (SPECT) during infusion of low-dose of dobutamine (DOB) and nitroglycerin (NTG). The subjects were 13 patients with coronary artery disease associated with wall motion abnormalities. Myocardial SPECT with MIBI was performed during infusion of NTG followed by infusion of DOB. Rest MIBI study was also performed on a separate day. The regional uptake of MIBI was visually evaluated by scoring (from 0=normal to 3=defect) in 9 regions of left ventricular wall in comparison with LVG or echocardiography data. The regional uptake of MIBI was quantitatively evaluated in 33 segments of left ventricular wall by a computer. The uptake of MIBI during infusion of both DOB and NTG was compared with that at rest study in the region of wall motion abnormalities. The mean uptake score of MIBI during infusion of both DOB and NTG and that of MIBI at rest was 1.8 and 2.1, respectively. The uptake of MIBI was significantly improved by infusion of both DOB and NTG (p<0.01). Percent of the peak activity of MIBI during infusion of both DOB and NTG and that of MIBI at rest in the region where the uptake score had been improved was 76.6±12.7% versus 74.0±13.1% (p<0.01). Percent of the peak activity of MIBI in the region where the uptake score had not been improved was 60.1±18.1% versus 60.7±18.7% (NS). Quantitative study also showed a significant improvement of MIBI uptake on the study of DOB and NTG. These results suggest that MIBI SPECT during infusion of both DOB and NTG infusion might be useful for evaluating myocardial viability. (S.Y.)

Segmentation of myocardial perfusion MR sequences with multi-band Active Appearance Models driven by spatial and temporal features

NARCIS (Netherlands)

Baka, N.; Milles, J.; Hendriks, E.A.; Suinesiaputra, A.; Jerosh Herold, M.; Reiber, J.H.C.; Lelieveldt, B.P.F.

2008-01-01

This work investigates knowledge driven segmentation of cardiac MR perfusion sequences. We build upon previous work on multi-band AAMs to integrate into the segmentation both spatial priors about myocardial shape as well as temporal priors about characteristic perfusion patterns. Different temporal

Myocardial imaging by direct injection of thallium-201 into coronary artery

International Nuclear Information System (INIS)

Sugihara, Hiroki; Inagaki, Suetsugu; Kubota, Yasushi

1988-01-01

Myocardial perfusion images were evaluated by direct injection of Thallium (Tl)-201 into coronary artery. Approximately 0.5 - 1 mCi of Tl-201 were instilled into the right coronary artery and/or the left coronary artery after coronary arteriography. Three images were obtained in the anterior, left anterior oblique and left lateral projections. Myocardial perfusion images of single photon emission computed tomography were also acquired in some patients. An image of supreme quality could be obtained in spite of small dose of Tl-201 since there was a lack of interference from background activity. Myocardial perfusion images corresponded to areas which were supplied by left or right coronary artery respectively. And the regional myocardial blood flow distribution of a coronary artery bypass graft could be revealed by instilling Tl-201 into the graft. Further, contribution of collateral channels to myocardial perfusion was showed. Not only left ventricle but also right ventricle was clearly visualized by injection of Tl-201 into right coronary artery. But in a case with arrhythmogenic right ventricular dysplasia, there was an area of decreased tracer uptake in the apex of the right ventricle which was identified as the site of dysplasia by electrophysiologic study. We conclude that direct injection of Tl-201 into coronary artery is an useful method to clarify the correlation between coronary anatomical findings and coronary perfusion and contribution of collaterals to myocardial perfusion, and also to detect the right ventricular myopathic site. (author)

Value and limitation of digital subtraction angiography for assessment of myocardial perfusion with varying coronary stenosis

International Nuclear Information System (INIS)

Ohtani, Nozomu

1988-01-01

We examined the value of digital subtraction angiography (DSA) for the assessment of regional myocardial perfusion by comparing with regional myocardial function in 10 anesthetized dogs. With varying degrees of reduction in left circumflex coronary artery (LCX) blood flow (CBF:categories of stenosis (S1-S5)), myocardial perfusion was assessed by injecting the contrast medium(1ml by power injector) selectively into LCX, and the regional myocardium with contrast was imaged with DSA. We recorded aortic pressure (AOP) and systolic wall thickening (%WTh: sonomicrometry) in the left ventricular posterior wall simultaneously with cine pulse. On the time-density curve obtained from the myocardial regin of interest, we calculated a time interval from the contrast injection to peak concentration (TPC) and exponential washout rate (T). Under varying LCX stenosis, there were no significant change of heart rate and mean AOP and a significant linear correlations were found between %WTh and both 1/TPC(r=0.51)and 1/T(r=0.55). At S1(CBF:100-90% of control), neither %WTh nor 1/TPC differed from control, but 1/T was significantly decreased (80% of contral p<0.01). At S3(CRF:79-60%) to S5(CBF:39-0%), all%WTh, 1/TPC and 1/T were significantly decreased from control (all p<0.01), however, at S5(CBF:39-0%) the value of 1/TPC(71% of control) and 1/T(33%) were not different from that at S4, whereas %WTh was markedly reduced and took place to systolic thinning.. Therefore, in critical coronary stenosis, 1/T was more sensitive than 1/TPC or wall dynamics for assessing myocardial perfusion, however, these indices from DSA had a considerable limitation for evaluating the severity of myocardial ischemia when CBF was markedly reduced. (author)

Combined evaluation of regional coronary artery calcium and myocardial perfusion by {sup 82}Rb PET/CT in the identification of obstructive coronary artery disease

Energy Technology Data Exchange (ETDEWEB)

Zampella, Emilia; Assante, Roberta; Nappi, Carmela; Mainolfi, Ciro Gabriele; Green, Roberta; Cantoni, Valeria; Klain, Michele; Cuocolo, Alberto [University Federico II, Department of Advanced Biomedical Sciences, Naples (Italy); Acampa, Wanda [University Federico II, Department of Advanced Biomedical Sciences, Naples (Italy); National Council of Research, Institute of Biostructure and Bioimaging, Naples (Italy); Gaudieri, Valeria; Panico, Mariarosaria [National Council of Research, Institute of Biostructure and Bioimaging, Naples (Italy); Petretta, Mario [University Federico II, Department of Translational Medical Sciences, Naples (Italy); Slomka, Piotr J. [Cedars-Sinai Medical Center, Department of Medicine, Los Angeles, CA (United States); UCLA, David Geffen School of Medicine, Los Angeles, CA (United States)

2018-04-15

Cardiac imaging with PET/CT allows measurement of coronary artery calcium (CAC), myocardial perfusion and coronary vascular function. We investigated whether the combined assessment of regional CAC score, ischemic total perfusion deficit (ITPD) and quantitative coronary vascular function would further improve the diagnostic accuracy of PET/CT in predicting obstructive coronary artery disease (CAD). We analyzed 113 patients with suspected CAD referred to {sup 82}Rb PET/CT myocardial perfusion imaging with available coronary angiographic data. Obstructive CAD was defined as ≥75% stenosis. The receiver operating characteristic area under curve (AUC) was applied to evaluate the ability of CAC score, ITPD, hyperemic myocardial blood flow (MBF) and coronary flow reserve (CFR) to identify CAD. Vessels with obstructive CAD (71 vessels) had higher ITPD (4.6 ± 6.2 vs. 0.6 ± 1.3) and lower hyperemic MBF (1.01 ± 0.5 vs. 1.75 ± 0.6 ml/min/g) and CFR (1.56 ± 0.6 vs. 2.38 ± 0.7; all p < 0.001) than those without. In prediction of per-vessel CAD, the AUCs for the models including CAC/ITPD/hyperemic MBF (0.869) and CAC/ITPD/CFR (0.875) were higher (both p < 0.01) than for the model including CAC/ITPD (0.790). Compared with CAC/ITPD, continuous net reclassification improvement was 0.69 (95% bootstrap confidence interval, CI, 0.365-1.088) for the CAC/ITPD/hyperemic MBF model and 0.99 (95% bootstrap CI 0.64-1.26) for the CAC/ITPD/CFR model. Hyperemic MBF and CFR provide incremental information about the presence of CAD over CAC score and perfusion imaging parameters. The combined use of CAC, myocardial perfusion imaging and quantitative coronary vascular function in may help predict more accurately the presence of obstructive CAD. (orig.)

The usefulness of the nuclear cardiology in the cellular implant in patients with severe myocardial damage

International Nuclear Information System (INIS)

Omelas A, M.; Arguero S, R.; Garrido G, M.H.; Rodriguez C, A.; Careaga, G.; Castano G, R.; Nambo, M.J.; Pascual P, J.; Ortega R, A.; Gaxiola A, A.; Magana S, J.A.; Estrada A, H.; Equipo de Tecnicos en Medicina Nuclear

2005-01-01

The recent therapeutic advances as the cellular implant as well as those different protocols of image acquisition in the field of the Nuclear Cardiology its have allowed that the patient with severe myocardial damage and without some possibility of revascularization is benefited with these advances. Doubtless the Tl-201 par excellence has an important paper for standardize the more appropriate therapeutic behavior for the heart attack patient; reason by this investigation protocol was developed. The objective of the study was to identify the heart attack regions without viable tissue with SPECT in patient with important myocardial damage without some possibility of traditional revascularization; for the 'Stem cell' cellular implantation therapy. The methodology it was carried out by a study of myocardial perfusion in 10 patients with important myocardial damage previous cellular implants, with PICANUC/ SPECT methodology and using a software (Emory Tool Box) for the image processing validated by the University of Emory Atlanta GA; and using as tracer the Tl - 201 to identify the heart attack regions without presence of viable tissue with an analysis model of 17 segments standardized for the left ventricle; qualifying this way the myocardial perfusion in: 0 (normal), 1 (light), 2 (moderate), 3 (severe), 4 (absent) and x (bad technique). The conclusions were that the SPECT study with PICANUC methodology with Tl-201 is safe and effective for the precise localization for the cellular implantation via direct intra myocardial. (Author)

Soil fertility shapes belowground food webs across a regional climate gradient.

Science.gov (United States)

Laliberté, Etienne; Kardol, Paul; Didham, Raphael K; Teste, François P; Turner, Benjamin L; Wardle, David A

2017-10-01

Changes in soil fertility during pedogenesis affect the quantity and quality of resources entering the belowground subsystem. Climate governs pedogenesis, yet how climate modulates responses of soil food webs to soil ageing remains unexplored because of the paucity of appropriate model systems. We characterised soil food webs along each of four retrogressive soil chronosequences situated across a strong regional climate gradient to show that belowground communities are predominantly shaped by changes in fertility rather than climate. Basal consumers showed hump-shaped responses to soil ageing, which were propagated to higher-order consumers. There was a shift in dominance from bacterial to fungal energy channels with increasing soil age, while the root energy channel was most important in intermediate-aged soils. Our study highlights the overarching importance of soil fertility in regulating soil food webs, and indicates that belowground food webs will respond more strongly to shifts in soil resources than climate change. © 2017 John Wiley & Sons Ltd/CNRS.

Clinical application of heart rate-synchronized myocardial SPECT with {sup 99m}Tc-labeled imaging agents for myocardial blood flow

Energy Technology Data Exchange (ETDEWEB)

Nishimura, Tsunehiko; Uehara, Toshiisa; Fukuchi, Kazuki; Tsujimura, Eiichiro; Hasegawa, Shinji; Ito, Yasushi; Hashimoto, Katsuji; Matsuda, Shinichi; Yutani, Kenji [Osaka Univ., Suita (Japan). Biomedical Research Center

1996-11-01

Application of gated SPECT to assess multiple heart functions simultaneously in authors` facility was reported. The myocardial SPECT at rest was performed 1 hr after intravenous administration of 740 MBq of {sup 99m}Tc-sestamibi with Toshiba 3-detector type gamma camera GCA9300/HG. R wave monitored by ECG was used as a trigger to record images of 360deg direction (90 sec/6deg direction, 20 directions x 3). Data were processed by Toshiba GMS-5500A or Hitachi-Medico RW3000. Percent CI (count increase at a myocardial region) was calculated by =(ES-ED)=/ED x 100, where ES and ED were computed by circumferential profile analysis of reconstruction images at the end-systole and end-diastole stages, respectively. Left ventricular ejection fraction was calculated from %AC (area change between areas of left ventricle at end-systolic and -diasystolic stages). Ventricular wall-motion was assessed by bullet display of the gated SPECT images. The present procedure is expected to be widely used as a routine test of the myocardial functions and is beneficial from a viewpoint of cost/performance. (K.H.)

SURGERY OF SYMPTOMATIC MYOCARDIAL BRIDGING

Directory of Open Access Journals (Sweden)

N. Maghamipour N. Safaei

2007-06-01

Full Text Available Myocardial bridging with systolic compression of the left anterior descending coronary artery (LAD may be associated with myocardial ischemia. In symptomatic myocardial bridging unresponsive to medical treatment, surgical unroofing of the left LAD can be performed. Little information is available about the long-term prognosis of patients with this coronary anomaly after the surgical unroofing, so we decided to evaluate the result of this operation. A total of 26 patients underwent surgical unroofing of myocardial bridging. Patients had a myocardial bridge of at least 3 cm in length in the middle of LAD and with more than 70% compression during systole. Unroofing was performed with cardiopulmonary bypass in 16 and with off pump technique in 10 patients. In 6 patients repeat angiographies for control of myotomy were done. In one of them a nonsignificant 20% narrowing was seen. Postoperative scintigraphic and angiographic studies demonstrated restoration of coronary flow and myocardial perfusion without residual myocardial bridges under beta-stimulation in 24 patients. Two patients had residual narrowing. With off pump technique, 1 patient had perforation of the right ventricle and 1 patient underwent reoperation because of incomplete unroofing during the first operation. None of the patients with cardiopulmonary bypass technique had residual chest pain or other complications. Surgical unroofing of myocardial bridging with the aid of cardiopulmonary bypass is a safe and easy procedure with low operative risk and with excellent functional results.

Myocardial perfusion imaging for detection of silent myocardial ischemia

International Nuclear Information System (INIS)

Beller, G.A.

1988-01-01

Despite the widespread use of the exercise stress test in diagnosing asymptomatic myocardial ischemia, exercise radionuclide imaging remains useful for detecting silent ischemia in numerous patient populations, including those who are totally asymptomatic, those who have chronic stable angina, those who have recovered from an episode of unstable angina or an uncomplicated myocardial infarction, and those who have undergone angioplasty or received thrombolytic therapy. Studies show that thallium scintigraphy is more sensitive than exercise electrocardiography in detecting ischemia, i.e., in part, because perfusion defects occur more frequently than ST depression and before angina in the ischemic cascade. Thallium-201 scintigraphy can be performed to differentiate a true- from a false-positive exercise electrocardiographic test in patients with exercise-induced ST depression and no angina. The development of technetium-labeled isonitriles may improve the accuracy of myocardial perfusion imaging. 11 references

Application of myocardial perfusion quantitative imaging for the evaluation of therapeutic effect in canine with myocardial infarction

International Nuclear Information System (INIS)

Liang Hong; Chen Ju; Liu Sheng; Zeng Shiquan

2000-01-01

Myocardial blood perfusion (MBP) ECT and quantitative analysis were performed in 10 canines with experimental acute myocardial infarct (AMI). The accuracy of main myocardial quantitative index, including defect volume (DV) and defect fraction (DF), was estimated and correlated with histochemical staining (HS) of infarcted area. Other 21/AMI canines were divided into Nd:YAG laser trans-myocardial revascularization treated group LTMR and control group. All canines were performed MBP ECT after experimental AMI. Results found that the infarcted volume (IV) measured by HS has well correlated (r 0.88) with DV estimated by myocardial quantitative analysis. But the DF values calculated by both methods was not significantly different (t = 1.28 P > 0.05). In LTMR group 27.5% +- 3.9%, the DF is smaller than control group 32.1% +- 4.6% (t = 2.49 P 99m Tc-MIBI myocardial perfusion SPECT and quantitative study can accurately predict the myocardial blood flow and magnitude of injured myocardium. Nd:YAG LTMR could improve myocardial blood perfusion of ischemic myocardium and decrease effectively the infarct areas

Myocardial kinetics of 123I-labeled-16-hexadecanoic acid

International Nuclear Information System (INIS)

Okada, R.D.; Elmaleh, D.; Werre, G.S.; Strauss, H.W.; Massachusetts General Hospital, Boston

1983-01-01

To determine if the myocardial clearance of omega 123 I-16-hexadecanoic acid ( 123 I-HDA) is affected by decreased coronary blodood flow, six anesthetized dogs had partial occlusion of the left anterior descending coronary artery. One hour later, 113 Sn-microspheres were injected into the left atrium, followed immediately by the IV administration of 123 I-HDA. Following injection, regional myocardial 123 I activities were monitored continuously with miniature cadmium telluride radiation detectors placed against the endocardium in both ischemic and nonischemic zones. After 3 h continuous monitoring, 46 Sc-microspheres were injected into the left atrium and the dogs were killed. Ischemic and nonischemic areas of myocardium were sectioned and counted in a well counter. (orig./WL)

Spatial distribution and temporal changes of pulmonary thallium uptake in myocardial perfusion studies

International Nuclear Information System (INIS)

Mannting, F.

1990-01-01

Spatial distribution and temporal changes in pulmonary thallium (Tl) uptake were assessed in 24 normal subjects and 35 patients with coronary artery disease (CAD). In studies carried out directly after stress and 3 h later, pulmonary Tl uptake was assessed as body surface area corrected absolute pulmonary uptake in the upper, middle and lower right lung regions, and in the total right lung and upper left lung. Pulmonary/myocardial (PM) uptake ratios for these 5 regions were calculated by mean pulmonary/mean background-corrected myocardial uptake. Additionally, wash-out was assessed for each region and for the myocardium. In normal subjects, the inital pulmonary Tl uptake, the PM ratios and Tl wash-out were greater in the lower lung regions than in the upper. In the late studies, no significant differences in Tl content or PM ratios were found among the regions. In patients with CAD, initial pulmonary Tl putake and PM ratios were greater in the lower than in the upper regions, and higher than for the normal subjects in all pulmonary regions (P<0.001). Tl wash-out was significantly higher in the low and middle regions versus the upper region (P<0.001) and higher in all regions than in normal subjects (P<0.001). In the late studies no significant differences in Tl content or PM ratios were found between any pulmonary regions. Pulmonary Tl content was, in all regions, higher in CAD than in normal subjects (P<0.01), as were the PM ratios (P<0.001). In conclusion, in normal subjects as well as in patients with CAD, pulmonary Tl uptake is greatest in the lower lung regions. Absolute pulmonary Tl uptake, PM ratios and pulmonary wash-out are greater in all lung regions in patients with CAD. Lower myocardial uptake may be the more important factor in producting the increased PM ratios in patients with CAD. Pulmonary redistribution is complete after 3-4 h. These characteristics strongly affect pulmonary Tl uptake ratios and wash-out assessments. (orig.)

Long-term cigarette smoking is associated with increased myocardial perfusion heterogeneity assessed by positron emission tomography

Energy Technology Data Exchange (ETDEWEB)

Meeder, J.G. [Department of Cardiology and National Research PET Center, University Hospital, Groningen (Netherlands); Blanksma, P.K. [Department of Cardiology and National Research PET Center, University Hospital, Groningen (Netherlands); Wall, E.E. van der [Department of Cardiology, University Hospital, Leiden (Netherlands); Anthonio, R.L. [Department of Cardiology and National Research PET Center, University Hospital, Groningen (Netherlands); Willemsen, A.T.M. [Department of Cardiology and National Research PET Center, University Hospital, Groningen (Netherlands); Pruim, J. [Department of Cardiology and National Research PET Center, University Hospital, Groningen (Netherlands); Vaalburg, W. [Department of Cardiology and National Research PET Center, University Hospital, Groningen (Netherlands); Lie, K.I. [Department of Cardiology and National Research PET Center, University Hospital, Groningen (Netherlands)

1996-11-01

The pathophysiology of smoking-related coronary events in patients with normal coronary arteries is incompletely understood. This study was conducted to explore, in subjects without symptoms of cardiovascular disease, the long-term effects of smoking on regional coronary artery vasoactivity, especially during sympathetic stimulation. In ten smoking and ten non-smoking sex- and age-matched healthy volunteers, segmental myocardial perfusion was studied using dynamic parametric nitrogen-13 ammonia positron emission tomography at rest and during sympathetic stimulation evoked by the cold pressor stimulation. Smokers demonstrated a higher myocardial perfusion at rest (116{+-}17 ml/min/100 g vs 96{+-}20 ml/min/100 g, P <0.01) and an impaired myocardial perfusion increase during cold pressor stimulation (1.02{+-}0.15 vs 1.18{+-}0.17, P <0.05). The heterogeneity of perfusion, expressed as coefficient of variation, was significantly different between the smoking and the non-smoking group. The coefficient of variation of segmental myocardial perfusion was higher in smokers at rest (17.5%{+-}4.2% vs 13.5%{+-}1.9%, P <0.05) and during cold pressor stimulation (17.0%{+-}3.2% vs 13.9%{+-}1.8%, P <0.05). We conclude that the long-term effects of smoking in healthy volunteers are associated with (1) increased myocardial perfusion at rest, (2) impaired myocardial perfusion response to cold pressor stimulation, and (3) increased myocardial perfusion heterogeneity both at rest and during cold pressor stimulation. These results may suggest that in healthy subjects the long-term effect of smoking is related to abnormal coronary artery vasoactivity, presumably induced by an interplay of regional endothelial dysfunction and autonomic dysregulation. (orig.). With 1 fig., 1 tab.

Regional rates of myocardial fatty acid metabolism: Comparison with coronary angiography and ventriculography

International Nuclear Information System (INIS)

Schad, N.; Vattimo, A.; Bertelli, P.

1990-01-01

In 50 patients, 1 mCi 123 I phenylpentadecanoic acid (IPPA) was injected at peak ergometric stress and 1500 frames were acquired (1 frame/s) with a high count rate gamma camera. Parametric images of rates of decrease and increase for different time intervals after stress were compared with coronary angiography and LV ventriculography, separately evaluating the 3 main coronary territories: 18/150 territories supplied by normal coronaries presented rather homogeneous regional clearing rates, whereas a gradual decrease in clearing rates towards the end of the territory (frequently with peripheral defects) was seen in all 87/150 territories with significant coronary narrowing. In local correspondence to clearing defects, initial IPPA accumulations could be observed with later onset of clearing between 10 and 25 min. In all 44/150 territories presented abnormal clearing rates, mostly with a patchy pattern, with normal coronary anatomy, but all except one had LV dysfunction and a clinical diagnosis of cardiomyopathy, diabetes mellitus or hypertensive disease. Twenty four of the 41 patients with CAD had, in correspondence to a prior myocardial infarction, minimum or missing metabolic activity frequently in circumscribed zones, partly separated by bridges of still viable tissue with preserved but reduced clearing rates. (orig.)

Holographic entanglement entropy for hollow cones and banana shaped regions

Energy Technology Data Exchange (ETDEWEB)

Dorn, Harald [Institut für Physik und IRIS Adlershof, Humboldt-Universität zu Berlin,Zum Großen Windkanal 6, D-12489 Berlin (Germany)

2016-06-09

We consider banana shaped regions as examples of compact regions, whose boundary has two conical singularities. Their regularised holographic entropy is calculated with all divergent as well as finite terms. The coefficient of the squared logarithmic divergence, also in such a case with internally curved boundary, agrees with that calculated in the literature for infinite circular cones with their internally flat boundary. For the otherwise conformally invariant coefficient of the ordinary logarithmic divergence an anomaly under exceptional conformal transformations is observed. The construction of minimal submanifolds, needed for the entanglement entropy of cones, requires fine-tuning of Cauchy data. Perturbations of such fine-tuning leads to solutions relevant for hollow cones. The divergent parts for the entanglement entropy of hollow cones are calculated. Increasing the difference between the opening angles of their outer and inner boundary, one finds a transition between connected solutions for small differences to disconnected solutions for larger ones.

[Myocardial microcirculation in humans--new approaches using MRI].

Science.gov (United States)

Wacker, Christian M; Bauer, Wolfgang R

2003-03-01

One crucial goal of magnetic resonance imaging (MRI) in patients with coronary artery disease (CAD) is the characterization of myocardial microcirculation that reflects tissue supply much better than detection and quantification of a stenosis itself. PERFUSION: Myocardial perfusion is one important parameter of microcirculation and it is commonly detected by first-pass techniques using contrast agents (CA). Despite the quantification of perfusion it is an indispensable component of a comprehensive diagnosis to determine the perfusion reserve, which is believed a good indicator for viability of myocardium. However, most MRI techniques for perfusion imaging are Ca based and this implies a restricted reproducibility in humans. Beyond it, most first-pass techniques are qualitative and not quantitative. REGIONAL BLOOD VOLUME: Another parameter of microcirculation is the regional intracapillary myocardial blood volume (RBV) that almost represents the whole intramyocardial blood volume due to its dominating volume fraction. The RBV reflects the autoregulatory adaptation of microvessels, e.g., a severe stenosis may lead to an increase of the RBV by capillary recruitment, and the RBV is reduced in scar areas. The RBV may be quantified by first-pass techniques; however, this demands a definite relation between signal intensity and concentration of the CA, which is difficult to find for the range of concentrations present during the first pass. Until recently, no techniques existed for the exact and noninvasive assessment of the RBV. CAPILLARY RECRUITMENT: The evaluation of the relevance of a coronary artery stenosis is of paramount interest for the therapeutic decision. A severe stenosis implies the activation of compensation mechanisms, which includes poststenotic dilation of the microvascular system. This lowering of the vascular resistance aims to maintain sufficient blood supply at least under resting conditions. However, many obstacles hamper the noninvasive assessment

Correlation of myocardial p-(123)I-iodophenylpentadecanoic acid retention with (18)F-FDG accumulation during experimental low-flow ischemia.

Science.gov (United States)

Shi, Cindy Q; Young, Lawrence H; Daher, Edouard; DiBella, Edward V R; Liu, Yi-Hwa; Heller, Eliot N; Zoghbi, Sami; Wackers, Frans J Th; Soufer, Robert; Sinusas, Albert J

2002-03-01

Myocardial ischemia is associated with reduced free fatty acid (FFA) beta-oxidation and increased glucose utilization. This study evaluated the potential of dynamic SPECT imaging of a FFA analog, p-(123)I-iodophenylpentadecanoic acid (IPPA), for detection of ischemia and compares retention of IPPA with (18)F-FDG accumulation. In a canine model of regional low-flow ischemia (n = 9), serial IPPA SPECT images (2 min per image) were acquired over 52--90 min. In a subset of dogs (n = 6), (18)F-FDG was injected after completing SPECT imaging and allowed to accumulate for 40 min before killing the animals. Flow was assessed with radiolabeled microspheres. Myocardial metabolism was evaluated independently by selective coronary arterial and venous sampling. Serial IPPA SPECT images showed an initial defect in the ischemic region (0.70% plus minus 0.03% ischemic-to-nonischemic ratio), which normalized within 48 min because of the slower IPPA clearance from the ischemic region (t(1/2) = 54.2 plus minus 3.3 min) relative to the nonischemic region (t(1/2) = 36.7 plus minus 5.6 min) (P < 0.05). Delayed myocardial IPPA and (18)F-FDG activities were correlated (r = 0.70; n = 576 segments), and both were maximally increased in segments with a moderate flow reduction (IPPA, 151% of nonischemic; (18)F-FDG, 450% of nonischemic; P < 0.05). Serial SPECT imaging showed delayed myocardial clearance of IPPA in ischemic regions with moderate flow reduction, which lead to increased late myocardial retention of IPPA. Retention of IPPA correlated with (18)F-FDG accumulation, supporting the potential of IPPA as a noninvasive marker of ischemic myocardium.

Left anterior descending coronary artery myocardial bridging by multislice computed tomography: Correlation with clinical findings

International Nuclear Information System (INIS)

Jodocy, Daniel; Aglan, Iman; Friedrich, Guy; Mallouhi, Ammar; Pachinger, Otmar; Jaschke, Werner; Feuchtner, Gudrun M.

2010-01-01

Objective: To assess the relationship between left anterior descending (LAD) coronary artery myocardial bridging detected by 64-slice computed tomography (CT) and clinical findings. Methods: 221 consecutive patients were examined with coronary 64-slice CT angiography. 21 patients with coronary stenosis >50% were excluded. The length, depth, and luminal narrowing of LAD myocardial bridges during systole and diastole were measured. CT findings were compared with the treadmill ECG-stress test, and clinical symptoms. Results: Myocardial bridges of the LAD were found in 23% of patients (51/221) (length, 14.9 ± 6.5 mm; depth, 2.6 ± 1.6 mm). A significant difference was noted between the LAD luminal diameter before the intramyocardial course and intramyocardially, for both diastole and systole (p 50% was found in 3/25 (8%). 30/51 (59%) of bridges were 'deep' (>2 mm myocardial depth), 21/51 (41%) were 'superficial'. The prevalence of a positive ECG-stress tests for the anterior myocardial region was significantly higher in patients with LAD myocardial bridges (34/50; 68%) compared to those without (28/144; 19.4%) (p < 0.001). There was no difference between 'superficial' and 'deep' LAD myocardial bridges in regard to a positive treadmill ECG-stress test. Typical angina was rare with 6%. Conclusion: LAD myocardial bridges are common findings and can possibly explain a positive exercise ECG-stress test for anterior myocardial ischemia. Intramyocardial LAD segments show mild-to-moderate luminal narrowing at rest, which is higher during end-systolic phase.

NOGA-guided analysis of regional myocardial perfusion abnormalities treated with intramyocardial injections of plasmid encoding vascular endothelial growth factor A-165 in patients with chronic myocardial ischemia: subanalysis of the EUROINJECT-ONE multicenter double-blind randomized study

DEFF Research Database (Denmark)

Gyongyosi, Mariann; Khorsand, Aliasghar; Zamini, Sholeh

2005-01-01

. The ROI was projected onto the baseline and follow-up rest and stress polar maps of the 99m-Tc-sestamibi/tetrofosmin single-photon emission computed tomography scintigraphy calculating the extent and severity (expressed as the mean normalized tracer uptake) of the ROI automatically. The extents of the ROI....... CONCLUSIONS: Projection of the NOGA-guided injection area onto the single-photon emission computed tomography polar maps permits quantitative evaluation of myocardial perfusion in regions treated with angiogenic substances. Injections of phVEGF A165 plasmid improve, but do not normalize, the stress...

Myocardial contusion following nonfatal blunt chest trauma

International Nuclear Information System (INIS)

Kumar, S.A.; Puri, V.K.; Mittal, V.K.; Cortez, J.

1983-01-01

Currently available diagnostic techniques for myocardial contusion following blunt chest trauma were evaluated. We investigated 30 patients prospectively over a period of 1 year for the presence of myocardial contusion. Among the 30 patients, eight were found to have myocardial contusion on the basis of abnormal electrocardiograms, elevated creatine phosphokinase MB fraction (CPK-MB), and positive myocardial scan. Myocardial scan was positive in seven of eight patients (87.5%). CPK-MB fraction was elevated in four of eight patients (50%). Definitive electrocardiographic changes were seen in only two of eight patients (25%). It appears that myocardial scan using technetium pyrophosphate and CPK-MB fraction determinations are the most reliable aids in diagnosis of myocardial contusion following blunt chest trauma

Thallium-201 myocardial scintigram in primary pulmonary hypertension

International Nuclear Information System (INIS)

Fujii, Isao; Handa, Shunnosuke; Yamazaki, Hajime; Nakamura, Yoshiro

1984-01-01

Right heart catheterization is needed for the diagnosis of pulmonary hypertension in patients with primary pulmonary hypertension (PPH), though the procedure was reported to have an unusually high risk. We examined the usefulness of thallium-201 myocardial scintigraphy for the evaluation of right ventricular overloading in patients with PPH. This study includes 5 patients with PPH, diagnosed by the clinical criteria of research committee of PPH in the Ministry of Health and Welfare in Japan (1976). Autopsy was done and diagnosis was confirmed in 4 cases. The right ventricular (RV) free wall was visualized in all cases. They were divided into 2 groups by the degree of visualization. The cases with heavier visualization had a higher pulmonary arterial resistence. The shape of the interventricular septum was deformed in all cases. It was straight in 3 cases and convex to the left ventricle (LV) in 3. In the later group, a systolic LV-RV pressure difference was less than 25 mmHg. One of these 3 cases showed reversed pressure difference. We concluded that thallium-201 myocardial scintigraphy could non-invasively assess the degree of RV overloading in PPH. (author)

Wall motion abnormality of myocardial infarction

International Nuclear Information System (INIS)

Hayashi, Senji; Tsuda, Takashi; Ojima, Kenji

1984-01-01

By use of the gated blood pool scan, we divided the left ventricular LAO 45 image into 8 sections with the center of the volume as the basal point, and devised a method of quantitative evaluation of the regional wall motion from 2 aspects: 1) wall movement and 2) phase abnormality. To evaluate the wall movement, we obtained the following indeces from count curves of each section: 1) EF1=(end-diastolic count-end-systolic count)/ end-diastolic count, 2) EF2=(maximum count-minimum count)/maximum count, and 3) the difference of the two (EF2-EF1). As indeces of the phase abnormality, the mean value of phases of the pixels (phase characteristics) and the standard deviation (variation) of each section were calculated. Furthermore, the phase delay of each section was calculated as the difference from the earliest phase value of the 8 sections. Control values and standard deviation were obtained from 8 healthy controls. By this method, we analyzed 20 patients with old myocardial infarction. And following results were obtained: 1. Applying this method, we could evaluate the regional wall motion of the left ventricle more precisely, and we considered it would be useful clinically. 2. The abnormal regional wall motion of old myocardial infarction were classified into 4 typical forms as follows: 1) the wall movement decreased extremely. 2) the wall movement decreased, but no phase delay recognized. 3) the wall movement did not decrease, but phase delay was recognized. 4) the wall movement decreased, and phase delay was recognized. (author)

Parvovirus Infection Is Associated With Myocarditis and Myocardial Fibrosis in Young Dogs.

Science.gov (United States)

Ford, Jordan; McEndaffer, Laura; Renshaw, Randall; Molesan, Alex; Kelly, Kathleen

2017-11-01

Perinatal parvoviral infection causes necrotizing myocarditis in puppies, which results in acute high mortality or progressive cardiac injury. While widespread vaccination has dramatically curtailed the epidemic of canine parvoviral myocarditis, we hypothesized that canine parvovirus 2 (CPV-2) myocardial infection is an underrecognized cause of myocarditis, cardiac damage, and/or repair by fibrosis in young dogs. In this retrospective study, DNA was extracted from formalin-fixed, paraffin-embedded tissues from 40 cases and 41 control dogs under 2 years of age from 2007 to 2015. Cases had a diagnosis of myocardial necrosis, inflammation, or fibrosis, while age-matched controls lacked myocardial lesions. Conventional polymerase chain reaction (PCR) and sequencing targeting the VP1 to VP2 region detected CPV-2 in 12 of 40 cases (30%; 95% confidence interval [CI], 18%-45%) and 2 of 41 controls (5%; 95% CI, 0.1%-16%). Detection of CPV-2 DNA in the myocardium was significantly associated with myocardial lesions ( P = .003). Reverse transcription quantitative PCR amplifying VP2 identified viral messenger RNA in 12 of 12 PCR-positive cases and 2 of 2 controls. PCR results were confirmed by in situ hybridization, which identified parvoviral DNA in cardiomyocytes and occasionally macrophages of juvenile and young adult dogs (median age 61 days). Myocardial CPV-2 was identified in juveniles with minimal myocarditis and CPV-2 enteritis, which may indicate a longer window of cardiac susceptibility to myocarditis than previously reported. CPV-2 was also detected in dogs with severe myocardial fibrosis with in situ hybridization signal localized to cardiomyocytes, suggesting prior myocardial damage by CPV-2. Despite the frequency of vaccination, these findings suggest that CPV-2 remains an important cause of myocardial damage in dogs.

Experimental identification of a comb-shaped chaotic region in multiple parameter spaces simulated by the Hindmarsh—Rose neuron model

Science.gov (United States)

Jia, Bing

2014-03-01

A comb-shaped chaotic region has been simulated in multiple two-dimensional parameter spaces using the Hindmarsh—Rose (HR) neuron model in many recent studies, which can interpret almost all of the previously simulated bifurcation processes with chaos in neural firing patterns. In the present paper, a comb-shaped chaotic region in a two-dimensional parameter space was reproduced, which presented different processes of period-adding bifurcations with chaos with changing one parameter and fixed the other parameter at different levels. In the biological experiments, different period-adding bifurcation scenarios with chaos by decreasing the extra-cellular calcium concentration were observed from some neural pacemakers at different levels of extra-cellular 4-aminopyridine concentration and from other pacemakers at different levels of extra-cellular caesium concentration. By using the nonlinear time series analysis method, the deterministic dynamics of the experimental chaotic firings were investigated. The period-adding bifurcations with chaos observed in the experiments resembled those simulated in the comb-shaped chaotic region using the HR model. The experimental results show that period-adding bifurcations with chaos are preserved in different two-dimensional parameter spaces, which provides evidence of the existence of the comb-shaped chaotic region and a demonstration of the simulation results in different two-dimensional parameter spaces in the HR neuron model. The results also present relationships between different firing patterns in two-dimensional parameter spaces.

Experimental identification of a comb-shaped chaotic region in multiple parameter spaces simulated by the Hindmarsh—Rose neuron model

International Nuclear Information System (INIS)

Jia Bing

2014-01-01

A comb-shaped chaotic region has been simulated in multiple two-dimensional parameter spaces using the Hindmarsh—Rose (HR) neuron model in many recent studies, which can interpret almost all of the previously simulated bifurcation processes with chaos in neural firing patterns. In the present paper, a comb-shaped chaotic region in a two-dimensional parameter space was reproduced, which presented different processes of period-adding bifurcations with chaos with changing one parameter and fixed the other parameter at different levels. In the biological experiments, different period-adding bifurcation scenarios with chaos by decreasing the extra-cellular calcium concentration were observed from some neural pacemakers at different levels of extra-cellular 4-aminopyridine concentration and from other pacemakers at different levels of extra-cellular caesium concentration. By using the nonlinear time series analysis method, the deterministic dynamics of the experimental chaotic firings were investigated. The period-adding bifurcations with chaos observed in the experiments resembled those simulated in the comb-shaped chaotic region using the HR model. The experimental results show that period-adding bifurcations with chaos are preserved in different two-dimensional parameter spaces, which provides evidence of the existence of the comb-shaped chaotic region and a demonstration of the simulation results in different two-dimensional parameter spaces in the HR neuron model. The results also present relationships between different firing patterns in two-dimensional parameter spaces

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

Science.gov (United States)

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

2001-08-13

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

New application of myocardial infarct map using a dual isotope single photon emission computed tomography (SPECT) of [99mTc]pyrophosphate and [201Tl]chloride in patients with acute myocardial infarction

International Nuclear Information System (INIS)

Hiroe, Michiaki; Muramatsu, Yasuji; Sugimoto, Keiichi; Tsujino, Motoyoshi; Maejima, Michihiro; Miyahara, Yasuhiro; Taniguchi, Koichi; Matsui, Susumu; Mizukawa, Katsumi.

1988-01-01

In 12 patients with acute myocardial infarction, a dual isotope SPECT was applied to describe a myocardial infarct map for detecting the site and the extent of the infarct. Threshold cut-off level was determined as 55 % for [ 99m Tc] and 35 % for [ 201 Tl] according to cardiac phantom studies. Multiple cardiac tomograms showed two different uptakes of the isotopes in indentical slices and regions. Then, color tomograms were described on the red and green image for [ 99m Tc] and for [ 201 Tl], respectively, and Bulls eye map was drawn in the two colored fashion as the myocardial infarct map. In all patients, the infarct map was successful to determine the exact site of the infarct and the overlapped area by the viable myocardium. In conclusion, this functional map of acute myocardial infarction may be useful for understanding three dimensional area of the infarct and the viable myocardium easily and exactly. (author)

Effects of spinal cord stimulation on myocardial blood flow assessed by positron emission tomography in patients with refractory angina pectoris

NARCIS (Netherlands)

Hautvast, RWM; Blanksma, PK; DeJongste, MJL; Pruim, J; vanderWall, EE; Vaalburg, W; Lie, KI

1996-01-01

Spinal cord stimulation in angina pectoris increases exercise capacity and reduces both anginal attacks and ischemic electrocardiographic signs. This suggests an anti-ischemic action, perhaps through changes in myocardial blood flow. In 9 patients, regional myocardial blood flow was studied with

Hydrogen Sulfide Donor GYY4137 Protects against Myocardial Fibrosis

Directory of Open Access Journals (Sweden)

Guoliang Meng

2015-01-01

Full Text Available Hydrogen sulfide (H2S is a gasotransmitter which regulates multiple cardiovascular functions. However, the precise roles of H2S in modulating myocardial fibrosis in vivo and cardiac fibroblast proliferation in vitro remain unclear. We investigated the effect of GYY4137, a slow-releasing H2S donor, on myocardial fibrosis. Spontaneously hypertensive rats (SHR were administrated with GYY4137 by intraperitoneal injection daily for 4 weeks. GYY4137 decreased systolic blood pressure and inhibited myocardial fibrosis in SHR as evidenced by improved cardiac collagen volume fraction (CVF in the left ventricle (LV, ratio of perivascular collagen area (PVCA to lumen area (LA in perivascular regions, reduced hydroxyproline concentration, collagen I and III mRNA expression, and cross-linked collagen. GYY4137 also inhibited angiotensin II- (Ang II- induced neonatal rat cardiac fibroblast proliferation, reduced the number of fibroblasts in S phase, decreased collagen I and III mRNA expression and protein synthesis, attenuated oxidative stress, and suppressed α-smooth muscle actin (α-SMA, transforming growth factor-β1 (TGF-β1 expression as well as Smad2 phosphorylation. These results indicate that GYY4137 improves myocardial fibrosis perhaps by a mechanism involving inhibition of oxidative stress, blockade of the TGF-β1/Smad2 signaling pathway, and decrease in α-SMA expression in cardiac fibroblasts.

Evaluation of myocardial abnormalities in collagen diseases by thallium-201 myocardial scintigraphy

Energy Technology Data Exchange (ETDEWEB)

Yamano, Shigeru; Kagoshima, Tadashi; Sugihara, Kiyotaka (Nara Medical Univ., Kashihara (Japan)) (and others)

1993-12-01

This study was performed to evaluate myocardial abnormalities in patients with collagen diseases by exercise and rest thallium-201 myocardial scintigrams. A total of 65 patients without ischemic ECG changes, consisting of 18 with systemic lupus erythematosus (SLE), 18 with polymyositis (PM), 8 with progressive systemic sclerosis (PSS), and 21 with Sjoegren's syndrome (SjS), was enrolled in this study. Reversible exercise-induced defects scintigraphically suggesting myocardial ischemia were noted in 8 cases of SLE, 4 cases of PM, 4 cases of PSS, and 3 cases of SjS. Nineteen patients had exercise-induced defects and underwent cardiac catheterization, 8 of whom had normal coronary angiograms. Fixed hypoperfusion areas were observed in one case of SLE, 6 cases of PM and 3 cases of SjS. Rest thallium-201 myocardial scintigram disclosed hypoperfusion areas which were not induced by exercise in 2 cases of SLE, 3 cases of PM, one case of PSS and 5 cases of SjS. Echocardiogram showed no significant differences in ejection fraction and % fractional shortening between the disease groups and healthy control group. These findings suggest that patients with collagen diseases have abnormalities of coronary circulation at the level of the intramural vasculature before cardiac function impairment, myocardial fibrosis and functional abnormalities at the cell membrane. (author).

Comparison of blood biochemics between acute myocardial infarction models with blood stasis and simple acute myocardial infarction models in rats

International Nuclear Information System (INIS)

Qu Shaochun; Yu Xiaofeng; Wang Jia; Zhou Jinying; Xie Haolin; Sui Dayun

2010-01-01

Objective: To construct the acute myocardial infarction models in rats with blood stasis and study the difference on blood biochemics between the acute myocardial infarction models with blood stasis and the simple acute myocardial infarction models. Methods: Wistar rats were randomly divided into control group, acute blood stasis model group, acute myocardial infarction sham operation group, acute myocardial infarction model group and of acute myocardial infarction model with blood stasis group. The acute myocardial infarction models under the status of the acute blood stasis in rats were set up. The serum malondialdehyde (MDA), nitric oxide (NO), free fatty acid (FFA), tumor necrosis factor-α (TNF-α) levels were detected, the activities of serum superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and the levels of prostacycline (PGI2), thromboxane A 2 (TXA 2 ) and endothelin (ET) in plasma were determined. Results: There were not obvious differences in MDA, SOD, GSH-Px and FFA between the acute myocardial infarction models with blood stasis in rats and the simple acute myocardial infarction models (P 2 and NO, and the increase extents of TXA 2 , ET and TNF-α in the acute myocardial infarction models in rats with blood stasis were higher than those in the simple acute myocardial infarction models (P 2 and NO, are significant when the acute myocardial infarction models in rats with blood stasis and the simple acute myocardial infarction models are compared. The results show that it is defective to evaluate pharmacodynamics of traditional Chinese drug with only simple acute myocardial infarction models. (authors)

Quantitative myocardial blood flow with Rubidium-82 PET

DEFF Research Database (Denmark)

Hagemann, Christoffer E; Ghotbi, Adam A; Kjær, Andreas

2015-01-01

Positron emission tomography (PET) allows assessment of myocardial blood flow in absolute terms (ml/min/g). Quantification of myocardial blood flow (MBF) and myocardial flow reserve (MFR) extend the scope of conventional semi-quantitative myocardial perfusion imaging (MPI): e.g. in 1) identificat......Positron emission tomography (PET) allows assessment of myocardial blood flow in absolute terms (ml/min/g). Quantification of myocardial blood flow (MBF) and myocardial flow reserve (MFR) extend the scope of conventional semi-quantitative myocardial perfusion imaging (MPI): e.g. in 1...... global MFR and major adverse cardiovascular events (MACE), and together with new diagnostic possibilities from measuring the longitudinal myocardial perfusion gradient, cardiac (82)Rb PET faces a promising clinical future. This article reviews current evidence on quantitative (82)Rb PET's ability...

Potential diagnostic value of regional myocardial adrenergic imaging using {sup 123}I-MIBG SPECT to identify patients with Lewy body diseases

Energy Technology Data Exchange (ETDEWEB)

Lebasnier, Adrien; Peyronnet, Damien; Bouvard, Gerard [University Hospital Center of Caen, Department of Nuclear Medicine, Caen (France); Lamotte, Guillaume; Defer, Gilles [University Hospital Center of Caen, Department of Neurology, Caen (France); Manrique, Alain [University Hospital Center of Caen, Department of Nuclear Medicine, Caen (France); Cyceron PET Centre, Caen (France); Normandie Universite, Caen (France); Agostini, Denis [University Hospital Center of Caen, Department of Nuclear Medicine, Caen (France); Normandie Universite, Caen (France)

2015-01-28

The aim of this study was to determine the potential diagnostic value of regional myocardial adrenergic {sup 123}I-metaiodobenzylguanidine (MIBG) single photon emission computed tomography (SPECT) imaging to identify patients with Lewy body diseases (LBD+). Sixty-four consecutive patients who underwent cardiac {sup 123}I-MIBG SPECT to differentiate LBD+, including Parkinson's disease (PD) and dementia with Lewy bodies (DLB), from patients without LBD (LBD-) were retrospectively reviewed. A neurologist expert in memory disorders determined the final clinical diagnosis by using international clinical diagnostic criteria. Planar [heart to mediastinum ratio (HMR)] and {sup 123}I-MIBG SPECT[innervation defect score (IDS)] using the 17-segment left ventricular model (five-point scale) were obtained 4 h after the injection of {sup 123}I-MIBG on a low-energy high-resolution (LEHR) collimator. Receiver-operating characteristic (ROC) analysis was performed to determine the optimal HMR and IDS cut-off values to discriminate LBD+ from LBD-. Of the 64 patients, 45 (70 %) were diagnosed LBD+ (DLB, n = 27; PD, n = 18) and 19 were diagnosed LBD- (5 other dementias, 14 other parkinsonisms). The HMR and IDS of LBD+ were significantly different from those of LBD- (1.30 ± 0.21 vs 1.65 ± 0.26, p < 0.001; 39 ± 28 vs 8 ± 16, p = 0.001). The optimal HMR and IDS cut-off values to discriminate LBD+ (n = 45) from LBD- (n = 19) were 1.47 and 6/68, providing a sensitivity and specificity of 82.2 and 84.2 % and 86.7 and 73.7 %, respectively. Regional myocardial adrenergic {sup 123}I-MIBG imaging SPECT has a potential diagnostic value to identify LBD+. (orig.)

SPECT Myocardial Blood Flow Quantitation Concludes Equivocal Myocardial Perfusion SPECT Studies to Increase Diagnostic Benefits.

Science.gov (United States)

Chen, Lung-Ching; Lin, Chih-Yuan; Chen, Ing-Jou; Ku, Chi-Tai; Chen, Yen-Kung; Hsu, Bailing

2016-01-01

Recently, myocardial blood flow quantitation with dynamic SPECT/CT has been reported to enhance the detection of coronary artery disease in human. This advance has created important clinical applications to coronary artery disease diagnosis and management for areas where myocardial perfusion PET tracers are not available. We present 2 clinical cases that undergone a combined test of 1-day rest/dipyridamole-stress dynamic SPECT and ECG-gated myocardial perfusion SPECT scans using an integrated imaging protocol and demonstrate that flow parameters are capable to conclude equivocal myocardial perfusion SPECT studies, therefore increasing diagnostic benefits to add value in making clinical decisions.

Effect of spinal cord stimulation on myocardial perfusion reserve in patients with refractory angina pectoris.

Science.gov (United States)

Saraste, Antti; Ukkonen, Heikki; Varis, Antti; Vasankari, Tuija; Tunturi, Satu; Taittonen, Markku; Rautakorpi, Pirkka; Luotolahti, Matti; Airaksinen, K E Juhani; Knuuti, Juhani

2015-04-01

Epidural spinal cord stimulation (SCS) provides symptom relief in refractory angina pectoris, but its mechanism of action remains incompletely understood. We studied effects of short-term SCS therapy on myocardial ischaemia tolerance, myocardial perfusion reserve (MPR), and endothelium-mediated vasodilatation induced by cold pressor test (CPT) in patients with refractory angina pectoris. We prospectively recruited 18 patients with refractory angina pectoris and studied them after implantation of SCS device at baseline before starting the therapy and after 3 weeks of continuous SCS therapy. Myocardial ischaemia was evaluated by dobutamine stress echocardiography. Global and regional myocardial blood flow (MBF) were measured using positron emission tomography and (15)O-water at rest, during adenosine stress, and in response to CPT. Systemic haemodynamics were comparable before and after 3 weeks of SCS at rest, during adenosine stress and during CPT. Appearance of angina pectoris induced by dobutamine stress was delayed after SCS therapy. Global MPR increased (P = 0.02) from 1.7 ± 0.6 at baseline to 2.0 ± 0.6 after 3-week SCS therapy. This was associated with a significant reduction in global MBF at rest and increase in MBF induced by adenosine in the ischaemic regions. Global MBF response to CPT was improved after SCS (0.27 ± 0.20 vs. 0.40 ± 0.15, P = 0.03). Short-term SCS therapy improved myocardial ischaemia tolerance, absolute MPR, and endothelium-mediated vasomotor function in refractory angina pectoris, indicating that this therapy can alleviate myocardial perfusion abnormalities in advanced CAD. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.

Myocardial contractile function in survived neonatal piglets after cardiopulmonary bypass

Directory of Open Access Journals (Sweden)

Popov Aron-Frederik

2010-11-01

Full Text Available Abstract Background Hemodynamic function may be depressed in the early postoperative stages after cardiac surgery. The aim of this study was the analysis of the myocardial contractility in neonates after cardiopulmonary bypass (CPB and mild hypothermia. Methods Three indices of left ventricular myocardial contractile function (dP/dt, (dP/dt/P, and wall thickening were studied up to 6 hours after CPB in neonatal piglets (CPB group; n = 4. The contractility data were analysed and then compared to the data of newborn piglets who also underwent median thoracotomy and instrumentation for the same time intervals but without CPB (non-CPB group; n = 3. Results Left ventricular dP/dtmax and (dP/dtmax/P remained stable in CPB group, while dP/dtmax decreased in non-CPB group 5 hours postoperatively (1761 ± 205 mmHg/s at baseline vs. 1170 ± 205 mmHg/s after 5 h; p max and (dP/dtmax/P there were no statistically significant differences between the two groups. Comparably, although myocardial thickening decreased in the non-CPB group the differences between the two groups were not statistically significant. Conclusions The myocardial contractile function in survived neonatal piglets remained stable 6 hours after cardiopulmonary bypass and mild hypothermia probably due to regional hypercontractility.

Thallium-201 myocardial imaging in the detection of coronary artery disease

International Nuclear Information System (INIS)

McKillop, J.H.; Murray, R.G.; Turner, J.G.; Gray, H.W.; Bessent, R.G.; Lorimer, A.R.; Greig, W.R.

1978-01-01

Thallium-201 myocardial imaging can detect abnormalities of myocardial perfusion. Visual interpretation of the images is complicated by some inhomogeneity of tracer uptake normally present. Using a quantitative approach we have established the regional variation of Thallium-201 uptake present in 23 normal controls and applied the same technique to 49 patients who had undergone selective coronary arteriography with left ventriculography because of chest pain. Half of the patients with significant coronary artery disease had abnormal rest Thallium-201 images, usually corresponding to areas of abnormal wall motion at ventriculography. Stress Thallium-201 images were abnormal in over 90% of patients with coronary artery disease. The stress image abnormalities and the arteriographic lesions correlated well in most patients with single and double vessel disease but in triple vessel disease the correspondence between the two studies was poor. Two of a group of patients with normal coronary arteriograms had abnormal Thallium-201 images due to other myocardial pathology. Our technique was highly sensitive in the non-invasive detection of significant coronary artery disease in a group of patients with chest pain. A small number of positive studies were also encountered due to other myocardial disorders. (author)

Myocardial scintigraphy: methods and indications

International Nuclear Information System (INIS)

Knapp, W.H.

1993-01-01

Myocardial scintigraphy comprises perfusion imaging using TI-201 or - more recently - Tc-99m-labeled compounds with high affinity to myocytes. Imaging with these agents has become an important procedure in the detection of coronary artery disease, particularly in patients with non-diagnostic stress-ECG, in the functional evaluation of coronary stenoses after angiographical documentation in order to meet the adequate therapy decision, in therapy monitoring and follow-up, in the post infarction assessment of myocardial viability and differentiation between severe ischemia and scar and, occasionally, in acute ischemia. The use of positron emitters does not offer significant advantages for mere perfusion imaging, but is indispensable for the scintigraphic investigation of certain aspects of myocardial metabolism, particularly for the differentiation of viable ischemic wall segments from irreversibly damaged tissue. Imaging of myocardial necrosis has been improved by the introduction of labeled antimyosin antibody fragments and offers a considerable clinical potential in the diagnosis of myocarditis and cardiac transplant rejection. Neurohumoral aspects are increasingly involved in our understanding of myocardial failure. Scintigraphy of innervation/neurotransmission contributes to the investigation of pathophysiological alterations in myocardial insufficiency and in heart transplants. (orig.) [de

Myocardial imaging in the noninvasive evaluation of patients with suspected ischemic heart disease

International Nuclear Information System (INIS)

Pitt, B.; Strauss, H.W.

1976-01-01

Three noninvasive radioactive tracer techniques for evaluating patients with ischemic heart disease are described: (1) myocardial perfusion imaging, (2) acute infarct imaging, and (3) the gated blood pool scan. Myocardial perfusion imaging with tracers that distribute in the myocardium in relation to regional blood flow allows detection of patients with transmural and nontransmural infarction by the finding of decreased tracer concentration in the affected region of the myocardium. If these tracers are injected at the time of maximal stress to patients with significant coronary arterial stenosis but without infarction, areas of transient ischemia can be identified as zones of decreased tracer concentration not found when an examination is performed at rest. Acute infarct imaging with tracers that localize in acutely damaged tissue permits separation of patients with acute myocardial necrosis from those without infarction and those with more chronic damage. The gated blood pool scan permits assessment of left ventricular function and regional wall motion. The measurement of ventricular volumes, ejection fraction and regional wall motion adds significantly to the determination of hemodynamic variables in assessing patients with acute infarction. The technique also permits detection of right ventricular dysfunction. Performance of a combination of these radioactive tracer techniques is often advantageous, particularly in patients with suspected infarction. The techniques can establish whether infarction is present, whether it is acute, where the damage is located and how extensive it is; they can also provide a measure of the effect of this damage on left ventricular function

Long-term cigarette smoking is associated with increased myocardial perfusion heterogeneity assessed by positron emission tomography

International Nuclear Information System (INIS)

Meeder, J.G.; Blanksma, P.K.; Wall, E.E. van der; Anthonio, R.L.; Willemsen, A.T.M.; Pruim, J.; Vaalburg, W.; Lie, K.I.

1996-01-01

The pathophysiology of smoking-related coronary events in patients with normal coronary arteries is incompletely understood. This study was conducted to explore, in subjects without symptoms of cardiovascular disease, the long-term effects of smoking on regional coronary artery vasoactivity, especially during sympathetic stimulation. In ten smoking and ten non-smoking sex- and age-matched healthy volunteers, segmental myocardial perfusion was studied using dynamic parametric nitrogen-13 ammonia positron emission tomography at rest and during sympathetic stimulation evoked by the cold pressor stimulation. Smokers demonstrated a higher myocardial perfusion at rest (116±17 ml/min/100 g vs 96±20 ml/min/100 g, P <0.01) and an impaired myocardial perfusion increase during cold pressor stimulation (1.02±0.15 vs 1.18±0.17, P <0.05). The heterogeneity of perfusion, expressed as coefficient of variation, was significantly different between the smoking and the non-smoking group. The coefficient of variation of segmental myocardial perfusion was higher in smokers at rest (17.5%±4.2% vs 13.5%±1.9%, P <0.05) and during cold pressor stimulation (17.0%±3.2% vs 13.9%±1.8%, P <0.05). We conclude that the long-term effects of smoking in healthy volunteers are associated with (1) increased myocardial perfusion at rest, (2) impaired myocardial perfusion response to cold pressor stimulation, and (3) increased myocardial perfusion heterogeneity both at rest and during cold pressor stimulation. These results may suggest that in healthy subjects the long-term effect of smoking is related to abnormal coronary artery vasoactivity, presumably induced by an interplay of regional endothelial dysfunction and autonomic dysregulation. (orig.). With 1 fig., 1 tab

Analysis of changes in sagging type ST-T segment induced by exercise. Assessment of regional myocardial blood flow using quantitative 13NH3 positron emission tomography

International Nuclear Information System (INIS)

Watanabe, Takuya; Akutsu, Yasushi; Okazaki, Osamu

1995-01-01

Regional myocardial blood flow (RMBF) associated with exercise-induced ST depression was assessed using 13 NH 3 positron emission tomography (PET) to determine the significance of horizontal and sagging type ST segments. The subjects were 25 patients with angina pectoris, 25 patients with myocardial infarction, and 5 healthy male volunteers. Eleven regions of interests (ROI) were prepared to calculate RMBF. ST segments were unchanged in 27 patients (Group A) and were depressed in 23 patients (Group B). A 10% increase in RMBF was significantly observed in Group A (74.1%) than Group B (34.8%). In Group B, ST depression was divided into horizontal type (8 patients) and sagging type (15 patients). According to the type of ST depression, RMBF was increased by 10% or more in 50% (4/8) for horizontal type and in 26.7% (4/15) for sagging type. These findings suggested that unfavorable increase in RMBF in stenosiss-related coronary vessels may contribute to the development of ST depression induced by exercise. A constant increase in RMBF in all ROIs, including those with unfavorable RMBF increase, may be involved in the occurrence of horizontal type ST depression; sagging type ST depression may, however, occur by an increased difference in blood flow between unfavorable and favorable RMBF. (N.K.)

[Performance of Thallium 201 rest-redistribution spect to predict viability in recent myocardial infarction].

Science.gov (United States)

Coll, Claudia; González, Patricio; Massardo, Teresa; Sierralta, Paulina; Humeres, Pamela; Jofré, Josefina; Yovanovich, Jorge; Aramburú, Ivonne; Brugère, Solange; Chamorro, Hernán; Ramírez, Alfredo; Kunstmann, Sonia; López, Héctor

2002-03-01

The detection of viability after acute myocardial infarction is primordial to select the most appropriate therapy, to decrease cardiac events and abnormal remodeling. Thallium201 SPECT is one of the radionuclide techniques used to detect viability. To evaluate the use of Thallium201 rest-redistribution SPECT to detect myocardial viability in reperfused patients after a recent myocardial infarction. Forty one patients with up to of 24 days of evolution of a myocardial infarction were studied. All had angiographically demonstrated coronary artery disease and were subjected to a successful thrombolysis, angioplasty or bypass grafting. SPECT Thallium201 images were acquired at rest and after 4 h of redistribution. These results were compared with variations in wall motion score, studied at baseline and after 3 or 4 months with echocardiography. The sensitivity of rest-redistribution Thallium201 SPECT, to predict recovery of wall motion was 91% when patient analysis was performed and 79% when segmental analysis was done in the culprit region. The figures for specificity were 56 and 73% respectively. Rest-distribution Thallium201 SPECT has an excellent sensitivity to predict myocardial viability in recent myocardial infarction. The data obtained in this study is similar to that reported for chronic coronary artery disease.

Generator-produced rubidium-82 positron emission tomography myocardial perfusion imaging. From basic aspects to clinical applications

International Nuclear Information System (INIS)

Yoshinaga, Keiichiro; Klein, R.; Tamaki, Nagara

2010-01-01

Cardiovascular disease is the leading cause of death in modern industrialized countries with an aging population. This fact has fueled the need for innovative diagnostic testing intended to improve coronary artery disease (CAD) patient care. Detection of myocardial ischemia using myocardial perfusion imaging (MPI) plays an important role for CAD diagnosis and the prediction of future risk of cardiovascular events. Positron emission tomography (PET) MPI has high diagnostic accuracy and can estimate regional myocardial blood flow (MBF) in patients with CAD. Rubidium-82 ( 82 Rb) is a generator-produced PET myocardial perfusion tracer and has been widely used in North America in clinical practice. 82 Rb PET has recently become available in some cardiovascular centers in Europe and Japan. Clinical trials are expected in both regions. 82 Rb PET has high diagnostic accuracy and recent data have shown its prognostic value. Thus, 82 Rb PET would greatly contribute to CAD patients' care. 82 Rb PET can also be used to quantify MBF. This review describes the current status of 82 Rb MPI from basic principles to clinical implications. This paper also highlights the recent development of MBF quantification using 82 Rb PET. (author)

Quantitative Assessment of Myocardial Infarction by In-111 Antimyosin Antibody

Energy Technology Data Exchange (ETDEWEB)

Lee, Myung Chul; Lee, Kyung Han; Choi, Yoon Ho; Chung, June Key; Park, Young Bae; Koh, Chang Soon [Seoul National University College of Medicine, Seoul (Korea, Republic of); Moon, Dae Hyuk [Asan Medical Center, Ulsan University College of Medicine, Seoul (Korea, Republic of)

1991-03-15

Infarct size is a major determinant of prognosis after acute myocardial infarction. Up to date, however, clinically available tests to estimate this size have not been sufficiently accurate. Twelve lead electrocardiogram and wall motion abnormality measurement are not quantitative, and creatine phosphokinase (CPK) measurement is inaccurate in the presence of reperfusion or right ventricular infarction. Methods have been developed to localize and size acute myocardial infarcts with agents that are selectively sequestered in areas of myocardial damage, but previously used agents have lacked sufficient specificity. Antibodies that bind specifically only to damaged myocardial cells may resolve this problem and provide an accurate method for noninvasively measuring infarct size. We determined the accuracy with which infarcted myocardial mass can be measured using single photon emission computed tomography (SPECT) and radiolabeled antimyosin antibodies. Seven patients with acute myocardial infarction and one stable angina patient were injected with 2 mCi of Indium-111 labeled antimyosin antibodies. Planar image and SPECT was performed 24 hours later. None of the patients had history of prior infarcts, and none had undergone reperfusion techniques prior to the study, which was done within 4 days of the attack. Planar image showed all infarct patients to have positive uptakes in the cardiac region. The location of this uptake correlated to the infarct site as indicated by electrocardiography in most of the cases. The angina patient, however, showed no such abnormal uptake. Infarct size was determined from transverse slices of the SPECT image using a 45% threshold value obtained from a phantom study. Measured infarct size ranged from 40 to 192 gr. There was significant correlation between the infarct size measured by SPECT and that estimated from serial measurements of CPK (r=0.73, p<0,05). These date suggest that acute myocardial infarct size can be accurately measured

Dynamic myocardial perfusion in a porcine balloon-induced ischemia model using a prototype spectral detector CT

Science.gov (United States)

Fahmi, Rachid; Eck, Brendan L.; Fares, Anas; Levi, Jacob; Wu, Hao; Vembar, Mani; Dhanantwari, Amar; Bezerra, Hiram G.; Wilson, David L.

2015-03-01

Myocardial CT perfusion (CTP) imaging is an application that should greatly benefit from spectral CT through the significant reduction of beam hardening (BH) artifacts using mono-energetic (monoE) image reconstructions. We used a prototype spectral detector CT (SDCT) scanner (Philips Healthcare) and developed advanced processing tools (registration, segmentation, and deconvolution-based flow estimation) for quantitative myocardial CTP in a porcine ischemia model with different degrees of coronary occlusion using a balloon catheter. The occlusion severity was adjusted with fractional flow reserve (FFR) measurements. The SDCT scanner is a single source, dual-layer detector system, which allows simultaneous acquisitions of low and high energy projections, hence enabling accurate projection-based material decomposition and effective reduction of BH-artifacts. In addition, the SDCT scanner eliminates partial scan artifacts with fast (0.27s), full gantry rotation acquisitions. We acquired CTP data under different hemodynamic conditions and reconstructed conventional 120kVp images and projection-based monoenergetic (monoE) images for energies ranging from 55keV-to-120keV. We computed and compared myocardial blood flow (MBF) between different reconstructions. With balloon completely deflated (FFR=1), we compared the mean attenuation in a myocardial region of interest before iodine arrival and at peak iodine enhancement in the left ventricle (LV), and we found that monoE images at 70keV effectively minimized the difference in attenuation, due to BH, to less than 1 HU compared to 14 HU with conventional 120kVp images. Flow maps under baseline condition (FFR=1) were more uniform throughout the myocardial wall at 70keV, whereas with 120kVp data about 12% reduction in blood flow was noticed on BH-hypoattenuated areas compared to other myocardial regions. We compared MBF maps at different keVs under an ischemic condition (FFR < 0.7), and we found that flow

Myocardial fatty acid imaging using iodine-123-BMIPP in patients with hypertensive intracranial hemorrhage

International Nuclear Information System (INIS)

Hashizume, Toshikazu; Sakai, Yasuhito; Hayashi, Yasushi

2000-01-01

An evaluation of myocardial fatty acid metabolism in hypertensive patients with major complication has not been previously established. To assess the myocardial fatty acid metabolism in hypertensive patients with intracranial hemorrhage (IH), we performed myocardial image using 123 I-15-p-iodophenyl-3-methyl pentadecanoic acid (BMIPP). Seventeen hypertensive patients with IH (HIH) and 27 hypertensive patients without IH (HT) were studied. A dose of 111 MBq of BMIPP was injected intravenously at rest, and a myocardial image was recorded 30 minutes after the injection. Myocardial perfusion image using Thallium-201 (Tl) was also performed within 2 weeks after BMIPP study. The regional myocardial uptakes of BMIPP and Tl were visually assessed in 17 segments with a four-point scoring system (0=absent to 3=normal uptake). Cardiac hypertrophy was evaluated by electrocardiogrpahy (ECG) and two-dimensional ultrasonic cardiography (UCG). Sum of uptake scores of Tl was similar in both groups (45.1±5.4 vs. 47.9±4.2), but that of BMIPP in HIH was lower than HT (35.9±7.9 vs 45.6±4.8, p<0.001). Evaluation of cardiac hypertrophy using ECG and UCG revealed no significant difference between two groups. HIH have much more eccentric hypertrophy in UCG study than HT (53% vs. 37%). These data suggest that hypertensive patients with intracranial hemorrhage have a more impaired myocardial fatty acid metabolism compared to the hypertensive patients with similar cardiac hypertrophy. BMIPP imaging might be useful to evaluate the severity of myocardial fatty acid metabolism in hypertensive patients. (author)

Evaluation of myocardial involvement in Duchenne's progressive muscular dystrophy with thallium-201 myocardial perfusion imaging

International Nuclear Information System (INIS)

Kawai, Naoki; Sotobata, Iwao; Okada, Mitsuhiro

1985-01-01

Myocardial involvement in progressive muscular dystrophy of the Duchenne type was evaluated in 19 patients using thallium-201 myocardial perfusion imaging. A qualitative analysis was performed from five projection images by three experienced physicians. Distinct perfusion defects were shown in 13 patients, especially in the LV posterolateral or posterior wall (11 patients). There was no significant relationship between the presence of perfusion defects and the skeletal muscle involvements or thoracic deformities assessed by transmission computed tomography. Extensive perfusion defects were shown in 2 patients who died of congestive heart failure 1 to 2 years after the scintigraphic study. Progression of the myocardial scintigraphic abnormalities were considered to be minimal in 7 of 9 patients who underwent two serial scintigraphic studies over 2 to 3 years. It was concluded that thallium myocardial perfusion imaging is a useful clinical technique to assess myocardial involvement in Duchenne's progressive muscular dystrophy. (author)

Fatty acid myocardial imaging using 123I-β-methyl-iophenyl pentadecanoic acid (BMIPP): Comparison of myocardial perfusion and fatty acid utilization in canine myocardial infarction

International Nuclear Information System (INIS)

Nishimura, Tsunehiko; Sago, Masayoshi; Kihara, Koichi; Oka, Hisashi; Shimonagata, Tsuyoshi; Katabuchi, Tetsuro; Hayashi, Makoto; Uehara, Toshiisa; Hayashida, Kohei; Noda, Hiroyuki; Takano, Hisateru

1989-01-01

To evaluate the relationship between myocardial perfusion and fatty acid metabolism in canine myocardial infarction, 16 dogs were studied using thallium and 123 I-β-methyl-iodophenyl pentadecanoic acid (BMIPP). Eight dogs (group A) had left anterior coronary arterial occlusion (6 h ligation), 6 dogs (group B) had reperfusion (3 h ligation and 1 h reperfusion) and 2 dogs served as the normal control. Myocardial imaging with BMIPP was excellent, owing to its higher uptake and longer retention in myocardium and rapid blood disappearance in addition to diminished liver and lung uptake. The mean half time value which was generated from the BMIPP myocardial washout curve, was significantly larger in the reperfused myocardium. The gamma camera imaging showed uncoupling of BMIPP and thallium (BMIPP uptake greater than thallium uptake) in five dogs in group B. On the other hand, all dogs in group A had a persistent defect in BMIPP and thallium uptake. Our findings indicate that the combination of BMIPP and thallium for myocardial imaging supply different information about the zone of infarction and ischemia, which may be useful for the assessment of myocardial viability. (orig.)

Myocardial scintigraphy with thallium-201

International Nuclear Information System (INIS)

Schwaiger, M.; Silber, S.; Klein, U.; Rudolph, W.

1980-01-01

Thallium-201 myocardial scintigraphy is an important non-invasive method for assessment of coronary artery disease. Other applications of the method such as delineation of the right ventricular free wall in right ventricular overload, or the detection of hypertrophic cardiomyopathies or myocardial infiltrations are of subordinate importance. In heart disease such as congestive cardiomyopathy and mitral valve prolapse thallium-201 uptake defects have been described, the clinical implications of these findings, however, cannot be adequately interpreted at this time. Myocardial uptake of thallium-201 is an active process, dependent on and proportional to perfusion. Differentiation between myocardial ischemia and myocardial scar is based on the presence or absence of thallium-201 'redistribution'. That is, in the presence of acute reversible ischemia there is increased thallium-201 uptake in the post-ischemic phase in previously hypoperfused myocardium and, subsequently, equilibrium of the initially registered activity differences. 'Redistribution' has also been described in the resting scintigram of patients with severe coronary artery disease and chronic hypoperfusion. (orig.) [de

The application of phase analysis of gated myocardial perfusion imaging to assess left ventricular mechanical dyssynchrony in cardiovascular disease

International Nuclear Information System (INIS)

Wang Jianfeng; Wang Yuetao

2013-01-01

Left ventricular mechanical dyssynchrony is closely related to the severity of cardiovascular disease, it is essential to assess left ventricular mechanical dyssynchrony accurately for early prediction of adverse cardiac events and prognosis assessment of the cardiac resynchronization therapy. As a new technology to assess left ventricular mechanical dyssynchrony, the phase analysis of gated myocardial perfusion imaging (GMPI) can get both quantitative indicators of regional myocardial perfusion, evaluation of regional myocardial viability and scar tissue, as well as quantitative analysis of left ventricular function and left ventricular mechanical synchrony, it has broad application prospects in cardiovascular disease to assess left ventricular mechanical dyssynchrony and prognosis assessment. This review mainly described the applications of GMPI phase analysis in the cardiovascular disease. (authors)

Asymptotic shape of the region visited by an Eulerian walker.

Science.gov (United States)

Kapri, Rajeev; Dhar, Deepak

2009-11-01

We study an Eulerian walker on a square lattice, starting from an initial randomly oriented background using Monte Carlo simulations. We present evidence that, for a large number of steps N , the asymptotic shape of the set of sites visited by the walker is a perfect circle. The radius of the circle increases as N1/3, for large N , and the width of the boundary region grows as Nalpha/3, with alpha=0.40+/-0.06 . If we introduce stochasticity in the evolution rules, the mean-square displacement of the walker, approximately approximately N2nu, shows a crossover from the Eulerian (nu=1/3) to a simple random-walk (nu=1/2) behavior.

Myocardial Infarction Risk Due to Aircraft, Road, and Rail Traffic Noise.

Science.gov (United States)

Seidler, Andreas; Wagner, Mandy; Schubert, Melanie; Dröge, Patrik; Pons-Kühnemann, Jörn; Swart, Enno; Zeeb, Hajo; Hegewald, Janice

2016-06-17

Traffic noise can induce stress reactions that have effects on the cardiovascular system. The exposure-risk relationship between aircraft, road, and rail traffic noise and myocardial infarction is currently unknown. 19 632 patients from the Rhine-Main region of Germany who were diagnosed with myocardial infarction in the years 2006-2010 were compared with 834 734 control subjects. The assignment of persons to groups was performed on the basis of billing and prescription data from three statutory health insurance carriers. The exposure of all insurees to aircraft, road, and rail traffic noise in 2005 was determined from their residence addresses. As estimators of risk, odds ratios (OR) were calculated by logistic regression analysis, with adjustment for age, sex, regional social status variables, and individual social status (if available). The evaluation was performed on the basis of the continuous 24-hour noise level and the categorized noise level (in 5 decibel classes). The linear model revealed a statistically significant risk increase due to road noise (2.8% per 10 dB rise, 95% confidence interval [1.2; 4.5]) and railroad noise (2.3% per 10 dB rise [0.5; 4.2]), but not airplane noise. Airplane noise levels of 60 dB and above were associated with a higher risk of myocardial infarction (OR 1.42 [0.62; 3.25]). This higher risk is statistically significant if the analysis is restricted to patients who had died of myocardial infarction by 2014/2015 (OR 2.70 [1.08; 6.74]. In this subgroup, the risk estimators for all three types of traffic noise were of comparable magnitude (3.2% to 3.9% per 10 dB rise in noise level). In this study, a substantial proportion of the population was exposed to traffic noise levels that were associated with an albeit small increase in the risk of myocardial infarction. These findings underscore the importance of effective traffic noise prevention.

Dynamic HDA-123-I-myocardial scintigraphy after aortocoronary bypass grafting

International Nuclear Information System (INIS)

Fridrich, L.; Gassner, A.; Sommer, G.; Kneussl, M.; Pichler, M.; Klicpera, M.; Salomonowitz, E.

1986-01-01

In an attempt to evaluate the dynamics of fatty acid metabolism after aortocoronary bypass grafting (ACBG), ten patients were investigated after ACBG by HDA-I-123 myocardial scintigraphy. Tracer kinetics were followed for 90 min and compared to those of 36 non-grafted patients with different underlying heart diseases, including healthy volunteers. Regional analysis and mono-exponential curve fitting were used to evaluate tsub(1/2) (half-life of the early period of tracer elimination); biexponential curve analysis was used to calculate Ca/Cb, the ratio of a fast and a slow component of tracer elimination. Rest and stress MUGA-RNV served as discriminating parameters to discern between patient groups with normal and abnormal ventricular function. Group I (normal controls) encompassed ten patients with normal ventricular function, including three after ACBG, and group II seven patients after ACBG and with abnormal ventricular function. Group III had coronary artery disease (CAD) documented by angiography, and group IV by prior myocardial infarction. Group V included patients with cardiomyopathy. Regional analysis of group II revealed no significant differences to control regions (Gr I) for tsub(1/2) or Ca/Cb, but showed for Ca/Cb a nonsignificant shift toward group III values. However, group II differed significantly from group III and V. three patients with normal ventricular function after ACBG showed elimination values that were all well within the range of completely normal individuals. Thus our data support the assumption that a normal function is indicative of a normal metabolism. Following myocardial fatty acid metabolism during rest might be a helpful noninvasive tool for etiologic differentiation of disturbed ventricular function. (orig.)

Myocardial late gadolinium enhancement in specific cardiomyopathies by cardiovascular magnetic resonance: a preliminary experience.

Science.gov (United States)

Silva, Caterina; Moon, James C; Elkington, Andrew G; John, Anna S; Mohiaddin, Raad H; Pennell, Dudley J

2007-12-01

Late gadolinium enhancement cardiovascular magnetic resonance (CMR) can visualize myocardial interstitial abnormalities. The aim of this study was to assess whether regions of abnormal myocardium can also be visualized by late enhancement gadolinium CMR in the specific cardiomyopathies. A retrospective review of all referrals for gadolinium CMR with specific cardiomyopathy over 20 months. Nine patients with different specific cardiomyopathies were identified. Late enhancement was demonstrated in all patients, with a mean signal intensity of 390 +/- 220% compared with normal regions. The distribution pattern of late enhancement was unlike the subendocardial late enhancement related to coronary territories found in myocardial infarction. The affected areas included papillary muscles (sarcoid), the mid-myocardium (Anderson-Fabry disease, glycogen storage disease, myocarditis, Becker muscular dystrophy) and the global sub-endocardium (systemic sclerosis, Loeffler's endocarditis, amyloid, Churg-Strauss). Focal myocardial late gadolinium enhancement is found in the specific cardiomyopathies, and the pattern is distinct from that seen in infarction. Further systematic studies are warranted to assess whether the pattern and extent of late enhancement may aid diagnosis and prognostic assessment.

[Clinical significance of myocardial 123I-BMIPP imaging in patients with myocardial infarction].

Science.gov (United States)

Narita, M; Kurihara, T; Shindoh, T; Honda, M

1997-03-01

In order to clarify the characteristics of fatty acid metabolism in patients with myocardial infarction (MI), we performed myocardial imaging with 123I-beta-methyl-p-iodophenylpentadecanoic acid (BMIPP) and we compared these findings with exercise stress (Ex) and resting myocardial perfusion imaging with 99mTc-methoxyisobutylisonitrile (MIBI) and left ventricular wall motion index (WMI) which were obtained by left ventriculography. We studied 55 patients with MI, 14 patients with recent MI (RMI) and 41 patients with old MI (OMI), and myocardial images were divided into 17 segments and myocardial uptake of the radionuclide was graded from 0 (normal) to 3 (maximal abnormality). In 28 patients we compared segmental defect score (SDS) with WMI which were obtained by centerline method at the corresponded segments. As a whole, the mean total defect scores (TDSs) of BMIPP and Ex were similar and they were greater than the mean TDS of resting perfusion. In 30 patient (55%) TDS of BMIPP was greater than that of TDS of resting perfusion. In 24 patients perfusion abnormality developed by Ex and the location of BMIPP abnormality coincided with the abnormality of Ex. But in the other 6 patients Ex did not induce any abnormality and they were all RMI and infarcted coronary artery was patent. However in the group with TDS of BMIPP identical to TDS of resting perfusion (25 patients), 92% did not show myocardial perfusion abnormality after Ex. In the comparison of SDS and WMI, myocardial segments were divided into 3 groups; both SDSs of BMIPP and resting perfusion were normal or borderline abnormality (Group 1, 82 segments), SDS of resting perfusion was normal or borderline and SDS of BMIPP was definitely abnormal (Group 2, 10 segments) and both SDSs of BMIPP and resting perfusion were definitely abnormal (Group 3, 48 segments). In Group 1, WMS (-0.41 +/- 0.77) was significantly (p acid metabolism may appear in viable myocardium such as jeopardized myocardium and myocardium which

Reproducibility of an automatic quantitation of regional myocardial wall motion and systolic thickening on gated Tc-99m-MIBI myocardial SPECT

International Nuclear Information System (INIS)

Paeng, Jin Chul; Lee, Dong Soo; Cheon, Gi Jeong; Kim, Yu Kyeong; Chung, June Key; Lee, Myung Chul

2000-01-01

The aim of this study is to investigate the reproducibility of the quantitative assessment of segmental wall motion and systolic thickening provided by an automatic quantitation algorithm. Tc-99m-MIBI gated myocardial SPECT with dipyridamole stress was performed in 31 patients with known or suspected coronary artery disease (4 with single, 6 with two, 11 with triple vessel disease; ejection fraction 51±14%) twice consecutively in the same position. Myocardium was divided into 20 segments. Segmental wall motion and systolic thickening were calculated and expressed in mm and % increase respectively, using AutoQUANT TM software. The reproducibility of this quantitative measurement of wall motion and thickening was tested. Correlations between repeated measurements on consecutive gated SPECT were excellent for wall motion (r=0.95) and systolic thickening (r=0.88). On Bland-Altman analysis, two standard deviation was 2 mm for repeated measurement of segmental wall motion, and 20% for that of systolic thickening. The weighted kappa values of repeated measurements were 0.807 for wall motion and 0.708 for systolic thickening. Sex, perfusion, or segmental location had no influence on reproducibility. Segmental wall motion and systolic thickening quantified using AutoQUANT TM software on gated myocardial SPECT offers good reproducibility and is significantly different when the change is more than 2 mm for wall motion and more than 20% for systolic thickening

Evaluation of myocardial abnormalities in patients with collagen diseases by thallium-201 myocardial scintigram

Energy Technology Data Exchange (ETDEWEB)

Yamano, Shigeru (Nara Medical Univ., Kashihara (Japan))

1992-08-01

This study was performed to evaluate myocardial lesions in patients with collagen diseases by rest and exercise thallium-201 myocardial scintigraphies. A total of 76 patients without ischemic ECG changes, consisting of 27 cases of systemic lupus erythematosus (SLE), 17 cases of polymyositis or dermatomyositis (PM[center dot]DM), 11 cases of progressive systemic sclerosis (PSS), and 21 cases of Sjoegren's syndrome (SjS), were enrolled in this study. Reversible exercise-induced defects suggesting myocardial ischemia were noted in 12 cases of SLE, 5 cases of PM[center dot]DM, 3 cases of PSS, and 3 cases of SjS. Of the 23 patients who had exercise-induced defects, 9 patients showed normal coronary angiograms by cardiac catheterization. Fixed hypoperfusion areas were observed in 5 cases of SLE, 6 cases of PM[center dot]DM, 4 cases of PSS and 3 cases of SjS. Rest thallium-201 myocardial scintigraphy disclosed hypoperfusion areas, which were not induced by exercise, in 1 case of SLE, 4 cases of PM[center dot]DM, 1 case of PSS and 5 cases of SjS. Endomyocardial biopsy was performed on 20 patients. Myocardial lesions in PM[center dot]DM and PSS were more severe and wide spread than in SLE. Ejection fraction and fractional shortening evaluated by echocardiography had no significant differences between each disease group and the healthy control group. These findings suggest that patients with collagen diseases show the presence of abnormalities of coronary circulation at the level of the intramyocardial vasculature in the stage before impairment of cardiac function, myocardial fibrosis and functional abnormalities of the cell membrane level that were not dependent on myocardial ischemia. (author).

The myocardial perfusion imaging of bone marrow mesenchymal stem cell transplantation treated acute myocardial infarction in pig

International Nuclear Information System (INIS)

He Miao; Hou Xiancun; Li Yaomei; Zhou Peng; Qi Chunmei; Wu Weihuan; Li Li

2006-01-01

Objective: To evaluate the clinical value of bone marrow mesenchymal stem cell transplantation on acute myocardial infarction in pig with myocardial perfusion imaging. Methods: Acute myocardial infarction models were established by 21 minitype Chinese pigs and were divided into two groups. After 10 days, experimental group (n=11) was transplanted with bone marrow mesenchymal stem cell at the infarct areas, and the control group (n=10) with incubation solution. Before and eight weeks after transplantation, both groups were examined by 99 Tc m -methoxyisobutylisonitrile (MIBI) myocardial perfusion imaging and with semi-quantitative analysis. Besides, echocardiogram and immunohistochemistry were also performed. Results: There was significant difference of total myocardial perfusion abnormal segments (46 vs 26), infarct areas [(34±12)% vs (21±10)%] and myocardial ischemia score [(20.0±4.3) vs (12.1±3.6)] between two groups (P<0.05). Also, there were accordant results with echocardiogram and immunohistochemistry findings. Conclusions: Bone marrow mesenchymal stem cell transplantation may improve blood perfusion and viability of the ischemic areas: Myocardial perfusion imaging can accurately observe the survival of bone marrow mesenchymal stem cell transplanted at the infarct areas. (authors)

Embedding the shapes of regions of interest into a Clinical Document Architecture document.

Science.gov (United States)

Minh, Nguyen Hai; Yi, Byoung-Kee; Kim, Il Kon; Song, Joon Hyun; Binh, Pham Viet

2015-03-01

Sharing a medical image visually annotated by a region of interest with a remotely located specialist for consultation is a good practice. It may, however, require a special-purpose (and most likely expensive) system to send and view them, which is an unfeasible solution in developing countries such as Vietnam. In this study, we design and implement interoperable methods based on the HL7 Clinical Document Architecture and the eXtensible Markup Language Stylesheet Language for Transformation standards to seamlessly exchange and visually present the shapes of regions of interest using web browsers. We also propose a new integration architecture for a Clinical Document Architecture generator that enables embedding of regions of interest and simultaneous auto-generation of corresponding style sheets. Using the Clinical Document Architecture document and style sheet, a sender can transmit clinical documents and medical images together with coordinate values of regions of interest to recipients. Recipients can easily view the documents and display embedded regions of interest by rendering them in their web browser of choice. © The Author(s) 2014.

Dual myocardial scintigraphic imaging using 123I-BMIPP and 201Tl in patients with Duchenne's progressive muscular dystrophy

International Nuclear Information System (INIS)

Sasaki, Akira

1996-01-01

Dual single photon emission computed tomography (SPECT) was performed in 30 patients with Duchenne's muscular dystrophy (DMD) using 201 thallium (Tl) for myocardial perfusion 123 I-β-methyl-p-iodophenylpentadecanoic acid (BMIPP) for myocardial fatty acid metabolism scintigraphy. The left ventricle was divided into 9 regions, and accumulation of the radiotracers was assessed visually for each region to calculate defect score for each tracer. There was some degree of decrease in the myocardial accumulation of both tracers in all DMD patients. Reduced accumulation was most common at the apex (BMIPP, 70%; Tl, 63%), followed by the posterior wall, lateral wall, and anterior wall. It was less common on the apical side of the ventricular septum for both tracers (BMIPP, 3%; Tl, 17%). Accumulation of Tl was lower than BMIPP in 18/30 patients (60%) and higher in 9 (30%), while both tracers showed equal accumulation in 3 (10%). BMIPP showed higher accumulation than Tl in all regions but the septum. A significant negative correlation was found between the defect scores for both tracers and the left ventricular ejection fraction (LVEF) (r=-0.629 for Tl; r=-0.567 for BMIPP). The strongest negative correlation was that between the sum of the Tl and BMIPP defect scores and the LVEF (r=-0.681). Dual SPECT myocardial scintigraphy with Tl and BMIPP provided an accurate evaluation of the progression of cardiac lesions in DMD by detecting abnormalities of the myocardial metabolism of each substance thereby enabling the assessment of left ventricular function. (author)

Clinical usefulness of technetium-99m pyrophosphate and Tl-201 myocardial imaging for the estimation of myocardial infarction

Energy Technology Data Exchange (ETDEWEB)

Suzuki, Akio; Sato, Akihiko; Miyakoda, Hiroyuki; Watanabe, Toshiya; Itatsu, Hidetaka; Ueda, Osamu; Sakurai, Kuniteru; Kawai, Naoki; Sotobata, Iwao

1985-04-01

A correlative study was performed between the infarct size estimated by either technetium-99 pyrophosphate (Tc-PYP) or Tl-201 myocardial imaging, and the cumulative total creatinine phosphokinase activity (..sigma..CPK) or left ventricular ejection fraction (LVEF) in 40 patients with acute myocardial infarction. Tc-PYP infarct area (TcIA) and mean Tl-201 uptake ratio (MUR) were calculated as indices of myocardial infarct size. LVEF was evaluated by first pass method using Tc-PYP in the acute phase of myocardial infraction. In 23 patients with anterior myocardial infarction, a significant correlation was shown between either TcIA or anterior-wall MUR and ..sigma..CPK (r=0.81 and r=-0.69, respectively) and also between either TcIA or anterior-wall MUR and LVEF (r=-0.84 and r=0.80, respectively). In 17 patients with inferior myocardial infarction without additional involvement of right ventricular wall, inferior-wall MUR correlated with ..sigma..CPK (r=-0.74). No statically significant correlation was shown between TcIA and ..sigma..CPK, and also between either TcIA or inferior-wall MUR and LVEF. In conclusion, the infarct size estimated with Tc-PYP or Tl-201 myocardial imaging could be a useful clinical indicator of the severity of acute myocardial infarction especially in anterior wall. (author).

Left anterior descending coronary artery myocardial bridging by multislice computed tomography: Correlation with clinical findings

Energy Technology Data Exchange (ETDEWEB)

Jodocy, Daniel; Aglan, Iman [Clinical Department of Radiology II, Innsbruck Medical University, Innsbruck (Austria); Friedrich, Guy [Clinical Department of Cardiology, Innsbruck Medical University, Innsbruck (Austria); Mallouhi, Ammar [Clinical Department of Radiology II, Innsbruck Medical University, Innsbruck (Austria); Pachinger, Otmar [Clinical Department of Radiology II, Innsbruck Medical University, Innsbruck (Austria); Clinical Department of Cardiology, Innsbruck Medical University, Innsbruck (Austria); Jaschke, Werner [Clinical Department of Radiology II, Innsbruck Medical University, Innsbruck (Austria); Feuchtner, Gudrun M. [Clinical Department of Radiology II, Innsbruck Medical University, Innsbruck (Austria)], E-mail: gudrun.feuchtner@i-med.ac.at

2010-01-15

Objective: To assess the relationship between left anterior descending (LAD) coronary artery myocardial bridging detected by 64-slice computed tomography (CT) and clinical findings. Methods: 221 consecutive patients were examined with coronary 64-slice CT angiography. 21 patients with coronary stenosis >50% were excluded. The length, depth, and luminal narrowing of LAD myocardial bridges during systole and diastole were measured. CT findings were compared with the treadmill ECG-stress test, and clinical symptoms. Results: Myocardial bridges of the LAD were found in 23% of patients (51/221) (length, 14.9 {+-} 6.5 mm; depth, 2.6 {+-} 1.6 mm). A significant difference was noted between the LAD luminal diameter before the intramyocardial course and intramyocardially, for both diastole and systole (p < 0.001); with a higher diameter reduction of 27% for end-systole compared to end-diastole with 15% (p = 0.006). Systolic LAD intramyocardial luminal narrowing >50% was found in 3/25 (8%). 30/51 (59%) of bridges were 'deep' (>2 mm myocardial depth), 21/51 (41%) were 'superficial'. The prevalence of a positive ECG-stress tests for the anterior myocardial region was significantly higher in patients with LAD myocardial bridges (34/50; 68%) compared to those without (28/144; 19.4%) (p < 0.001). There was no difference between 'superficial' and 'deep' LAD myocardial bridges in regard to a positive treadmill ECG-stress test. Typical angina was rare with 6%. Conclusion: LAD myocardial bridges are common findings and can possibly explain a positive exercise ECG-stress test for anterior myocardial ischemia. Intramyocardial LAD segments show mild-to-moderate luminal narrowing at rest, which is higher during end-systolic phase.

Imaging QRS complex and ST segment in myocardial infarction

DEFF Research Database (Denmark)

Bacharova, Ljuba; Bang, Lia E; Szathmary, Vavrinec

2014-01-01

BACKGROUND: Acute myocardial infarction creates regions of altered electrical properties of myocardium resulting in typical QRS patterns (pathological Q waves) and ST segment deviations observed in leads related to the MI location. The aim of this study was to present a graphical method for imaging...... the changes in the sequence of depolarization and the ST segment deviations in myocardial infarction using the Dipolar ElectroCARdioTOpography (DECARTO) method. MATERIAL AND METHODS: Simulated ECG data corresponding to intramural, electrically inactive areas encircled by transmural areas with slowed impulse...... propagation velocity in anteroseptal and inferior locations were used for imaging the altered sequence of depolarization and the ST vector. The ECGs were transformed to areas projected on the image surface so as to image the process of ventricular depolarization based on the orientation and magnitude...

Influence of arm positioning on tomographic thallium-201 myocardial perfusion imaging and the effect of attenuation correction

International Nuclear Information System (INIS)

Prvulovich, E.M.; Jarritt, P.H.; Vorontsova, E.; Bomanji, J.B.; Ell, P.J.

2000-01-01

Lateral attenuation in single-photon emission tomography (SPET) myocardial perfusion imaging (MPI) has been attributed to the left arm if it is held by the patient's side during data acquisition. As a result MPI data are conventionally acquired with the arms held above the head. The aims of this study were to determine the effect of imaging arms down on reconstructed tomographic images depicting regional myocardial thallium-201 distribution and to assess whether attenuation-corrected (AC) myocardial perfusion images acquired arms down could replace uncorrected (NC) images acquired arms up for routine clinical service. Twenty-eight patients referred for routine MPI underwent sequential 180 emission/transmission imaging for attenuation correction using an L-shaped dual-headed gamma camera (GE Optima) fitted with two gadolinium-153 scanning line sources. Delay data were acquired twice: once supine with the arms up and then supine with the arms down. Detector radius of rotation (ROR) for arms up and arms-down studies was recorded. For each data set, count density was measured in 17 segments of a polar plot and segmental uptake expressed relative to study maximum. Oblique images were assessed qualitatively by two observers blinded to study type for tracer distribution and overall quality. Transmission maps were assessed for truncation. Mean detector ROR was 190 mm for arms-up studies and 232 mm for arms-down studies (P 201 Tl distribution, particularly anterolaterally. There is lateral undercorrection in approximately 10% of AC arms-down studies, possibly because of attenuation map truncation. Image quality is reduced in about one-third of AC arms-down studies compared with NC arms-up studies. These data suggest that this attenuation correction method is not sufficiently robust to allow routine acquisition of MPI data with the arms down. (orig.)

Quantitative assessment of 201TlCl myocardial SPECT

International Nuclear Information System (INIS)

Uehara, Toshiisa

1987-01-01

Clinical evaluation of the quantitative analysis of Tl-201 myocardial tomography by SPECT (Single Photon Emission Computed Tomography) was performed in comparison with visual evaluation. The method of quantitative analysis has been already reported in our previous paper. In this study, the program of re-standardization in the case of lateral myocardial infarction was added. This program was useful mainly for the evaluation of lesions in the left circumflex coronary artery. Regarding the degree of diagnostic accuracy of myocardial infarction in general, quantitative evaluation of myocardial SPECT images was highest followed by visual evaluation of myocardial SPECT images, and visual evaluation of myocardial planar images. However, in the case of anterior myocardial infarction, visual evaluation of myocardial SPECT images has almost the same detectability as quantitative evaluation of myocardial SPECT images. In the case of infero-posterior myocardial infarction, quantitative evaluation was superior to visual evaluation. As for specificity, quantitative evaluation of SPECT images was slightly inferior to visual evaluation of SPECT images. An infarction map was made by quantitative analysis and this enabled us to determine the infarction site, extent and degree according to easily recognizable patterns. As a result, the responsible coronary artery lesion could be inferred correctly and the calculated infarction score could be correlated with the residual left ventricular function after myocardial infarction. (author)

Roles of myocardial blood volume and flow in coronary artery disease: an experimental MRI study at rest and during hyperemia

International Nuclear Information System (INIS)

McCommis, Kyle S.; Goldstein, Thomas A.; Pilgram, Thomas; Abendschein, Dana R.; Misselwitz, Bernd; Gropler, Robert J.; Zheng, Jie

2010-01-01

To validate fast perfusion mapping techniques in a setting of coronary artery stenosis, and to further assess the relationship of absolute myocardial blood volume (MBV) and blood flow (MBF) to global myocardial oxygen demand. A group of 27 mongrel dogs were divided into 10 controls and 17 with acute coronary stenosis. On 1.5-T MRI, first-pass perfusion imaging with a bolus injection of a blood-pool contrast agent was performed to determine myocardial perfusion both at rest and during either dipyridamole-induced vasodilation or dobutamine-induced stress. Regional values of MBF and MBV were quantified by using a fast mapping technique. Color microspheres and 99m Tc-labeled red blood cells were injected to obtain respective gold standards. Microsphere-measured MBF and 99m Tc-measured MBV reference values correlated well with the MR results. Given the same changes in MBF, changes in MBV are twofold greater with dobutamine than with dipyridamole. Under dobutamine stress, MBV shows better association with total myocardial oxygen demand than MBF. Coronary stenosis progressively reduced this association in the presence of increased stenosis severity. MR first-pass perfusion can rapidly estimate regional MBF and MBV. Absolute quantification of MBV may add additional information on stenosis severity and myocardial viability compared with standard qualitative clinical evaluations of myocardial perfusion. (orig.)

Roles of myocardial blood volume and flow in coronary artery disease: an experimental MRI study at rest and during hyperemia

Science.gov (United States)

McCommis, Kyle S.; Goldstein, Thomas A.; Abendschein, Dana R.; Misselwitz, Bernd; Pilgram, Thomas; Gropler, Robert J.

2010-01-01

Objective To validate fast perfusion mapping techniques in a setting of coronary artery stenosis, and to further assess the relationship of absolute myocardial blood volume (MBV) and blood flow (MBF) to global myocardial oxygen demand. Methods A group of 27 mongrel dogs were divided into 10 controls and 17 with acute coronary stenosis. On 1.5-T MRI, first-pass perfusion imaging with a bolus injection of a blood-pool contrast agent was performed to determine myocardial perfusion both at rest and during either dipyridamole-induced vasodilation or dobutamine-induced stress. Regional values of MBF and MBV were quantified by using a fast mapping technique. Color microspheres and 99mTc-labeled red blood cells were injected to obtain respective gold standards. Results Microsphere-measured MBF and 99mTc-measured MBV reference values correlated well with the MR results. Given the same changes in MBF, changes in MBV are twofold greater with dobutamine than with dipyridamole. Under dobutamine stress, MBV shows better association with total myocardial oxygen demand than MBF. Coronary stenosis progressively reduced this association in the presence of increased stenosis severity. Conclusions MR first-pass perfusion can rapidly estimate regional MBF and MBV. Absolute quantification of MBV may add additional information on stenosis severity and myocardial viability compared with standard qualitative clinical evaluations of myocardial perfusion. PMID:20182731

Effect of nicorandil on the myocardial tissue perfusion and myocardial cell injury in patients with diabetes after PCI

Directory of Open Access Journals (Sweden)

Xue-Li Ren1

2017-04-01

Full Text Available Objective: To study the effect of nicorandil on the myocardial tissue perfusion and myocardial cell damage in patients with diabetes after percutaneous coronary intervention (PCI. Methods: 68 patients with coronary heart disease and type 2 diabetes mellitus who received PCI in our hospital between May 2011 and September 2015 were collected and then divided into observation group and control group (n=34 according to the single-blind randomized control method. Control group of patients received PCI alone, and the observation group of patients received nicorandil therapy after PCI. After treatment, real-time myocardial ultrasound contrast was used to evaluate the myocardial perfusion of two groups of patients; blood biochemical analyzer was used to detect the contents of peripheral blood myocardial enzyme spectrum indexes; the ELISA method was used to detect the contents of serum oxidative stress indicators; RIA method was used to detect the contents of serum apoptosis molecules. Results: After treatment, the myocardial tissue perfusion parameters plateau peak intensity (A, slope rate of curve (β and myocardial blood flow (A×β levels of observation group were significantly higher than those of control group (P<0.05; peripheral blood myocardial enzyme spectrum indexes creatine kinase (CK, lactate dehydrogenase (LDH, troponin I (cTnI and glutamic oxalacetic transaminase (GOT contents of observation group were significantly lower than those of control group (P<0.05; serum vitamin E (VitE and vitamin C (VitC contents of observation group were significantly higher than those of control group while malondialdehyde (MDA, advanced oxidation protein products (AOPPs, soluble apoptosis-associated factor (sFas and soluble apoptosis-associated factor ligand (sFasL contents were lower than those of control group (P<0.05. Conclusion: Adjuvant nicorandil therapy can improve the myocardial perfusion and reduce the myocardial cell injury in patients with coronary

Evaluation of myocardial damage in Duchenne's muscular dystrophy with thallium-201 myocardial SPECT

International Nuclear Information System (INIS)

Tamura, Takuhisa; Shibuya, Noritoshi; Hashiba, Kunitake; Oku, Yasuhiko; Mori, Hideki; Yano, Katsusuke.

1993-01-01

Myocardial damage and cardiopulmonary functions in patients with Duchenne's muscular dystrophy (DMD) were assessed using thallium-201 myocardial single-photon emission computed tomography (SPECT) and technetium-99m multigated radionuclide angiography. Twenty-five patients with DMD were divided into 4 groups according to percent of perfusion defect (%PD) calculated by the bull's-eye method and age. PD was detected in 24 (96.0%) of 25 patients with DMD, and it spread from the left ventricular lateral wall to the anterior wall and/or interventricular septum. PD was detected even in a 6-year-old DMD boy. Patients in Group I (%PD≥10% and age<15 years old) were shown to have a higher risk of left-sided heart failure without respiratory failure. Patients in Group II (%PD≥10 and age≥15) showed decreased pulmonary function and worsened arterial blood gas values as compared with Group IV (%PD<10 and age≥15). There was no significant difference in cardiac function among the 4 groups. It is postulated that myocardial damage in Group II patients is dependent primarily on a deficiency of dystrophin and on chronic respiratory failure, and that some of them are at risk of cardiopulmonary failure. It is concluded that myocardial SPECT is useful for the early diagnosis of myocardial damage and evaluation of cardiopulmonary function in DMD patients. (author)

Myocardial imaging in acute myocardial infarction using β-methyl-p-(123I)-iodophenylpentadecanoic acid

International Nuclear Information System (INIS)

Naruse, Hitoshi; Itano, Midoriko; Kondo, Tomohiro

1992-01-01

Myocardial imaging using β-methyl-p-( 123 I)-iodophenylpentadecanoic acid (BMIPP) was performed in 11 patients with acute myocardial infarction. The left ventricular images were divided into 12 segments, and myocardial images with BMIPP were compared with coronary angiography (CAG), thallium-201 myocardial scintigraphy (Tl) and wall motion obtained by two-dimensional echocardiography (WM). When the culprit lesion was at the proximal point of the left anterior descending artery (LAD), all segments showed depressed uptake. In 3 cases with single vessel disease of the LAD, inferior wall of the basis showed reduced uptake of BMIPP despite the location of the culprit lesion. In cases with discordant uptake between the two tracers, BMIPP frequently showed more severely depressed uptake than Tl in the subacute phase, although the uptake of BMIPP correlated with that of Tl (τ=0.82, p<0.001). In such cases, the discordance was related to the improvement in WM from the acute phase to the convalescent phase. BMIPP uptake correlated with WM in the subacute phase (τ=0.50, p<0.001). BMIPP showed more severely depressed uptake while WM showed mild asynergy in most cases in which discordance was found between the BMIPP and WM findings. However, there was no correlation between the change in WM from the acute to subacute phases, or the uptakes of BMIPP and Tl alone. We concluded that the myocardial condition can be evaluated in detail in acute myocardial infarction by comparing the findings of BMIPP with those of Tl and WM. (author)

Reduction of myocardial blood flow reserve in idiopathic dilated cardiomyopathy without overt heart failure and its relation with functional indices: an echo-Doppler and positron emission tomography study.

Science.gov (United States)

Morales, Maria-Aurora; Neglia, Danilo; L'Abbate, Antonio

2008-08-01

Myocardial blood flow during pharmacological vasodilatation is depressed in patients with idiopathic dilated cardiomyopathy even the in absence of overt heart failure; the extent of myocardial blood flow abnormalities is not predictable by left ventricular ejection fraction (LVEF) and diastolic dimensions. To assess whether myocardial blood flow impairment in idiopathic dilated cardiomyopathy without overt heart failure can be related to Doppler-derived dP/dt and to echocardiographically determined left ventricular end systolic stress - which is linked to myocardial blood flow reserve in advanced disease. Twenty-six patients, New York Heart Association Class I-II, (LVEF 37.4 +/- 1.4%, left ventricular diastolic dimensions 62.6 +/- 0.9 mm) underwent resting/dipyridamole [13N]NH3 flow positron emission tomography and an ultrasonic study. Regional myocardial blood flow values (ml/min per g) were computed from positron emission tomography data in 13 left ventricular (LV) myocardial regions and averaged to provide mean myocardial blood flow and myocardial blood flow reserve, defined as dipyridamole/resting mean myocardial blood flow ratio. Resting myocardial blood flow was 0.686 +/- 0.045, dipyridamole myocardial blood flow 1.39 +/- 0.15 and myocardial blood flow reserve 2.12 +/- 0.2, lower than in controls (P < 0.01). The ratio dP/dt was directly related to dipyridamole myocardial blood flow and myocardial blood flow reserve (r = 0.552 and 0.703, P < 0.005 and P < 0.0001); no relation was found between myocardial blood flow and LVEF left ventricular diastolic dimensions, and left ventricular end systolic stress. In idiopathic dilated cardiomyopathy patients without overt heart failure, the extent of myocardial blood flow reserve impairment is related to dP/dt but not to more classical indices of left ventricular function.

Evaluation of myocardial fatty acid metabolism in the area of fill-in after thallium reinjection in patients with prior myocardial infarction

International Nuclear Information System (INIS)

Matsunari, Ichiro; Fujino, Susumu; Nishikawa, Takahiro; Ichiyanagi, Kenji; Taki, Junichi; Nakajima, Kenichi; Tonami, Norihisa; Hisada, Kinichi.

1995-01-01

Myocardial fatty acid utilization in the area with thallium fill-in after reinjection was assessed using 123 I-labeled 15-(p-iodophenyl) 3R, S-methylpentadecanoic acid (BMIPP). We studied 22 patients with prior myocardial infarction that revealed persistent defects on standard exercise-redistribution thallium imaging. In each patient, exercise-redistribution-reinjection thallium imaging was performed. Within two weeks of the thallium study, resting BMIPP imaging was performed 20 min after injection of BMIPP (148 MBq). Following qualitative analysis of the obtained thallium and BMIPP images, quantitative analysis was performed on the basis of relative regional uptake. Of 199 myocardial segments that showed persistent defects on exercise-redistribution images, 73 segments showed apparent fill-in on the reinjection images (fill-in positive), and the remaining 126 segments did not (fill-in negative). When BMIPP images were compared with the corresponding thallium reinjection images, reduced BMIPP uptake compared with thallium was frequently observed in the area of fill-in positive segments (65 of 73 segments, 89%). Quantitative analysis also showed decrease in BMIPP activity compared to thallium activity in the area of fill-in (49.7±16.1 vs. 65.8±16.0%, p<0.001). In contrast, only 24 of the 126 fill-in negative segments (19%) showed lower BMIPP uptake than thallium. These results suggest that impaired fatty acid utilization in the area of thallium new fill-in after reinjection already exists at resting condition. Thus, BMIPP imaging combined with exercise-redistribution-reinjection thallium imaging provides insights to understanding fatty acid utilization in ischemic but viable myocardium identified by thallium reinjection in patients with prior myocardial infarction. (author)

Detecting Myocardial Ischemia With 99mTechnetium-Tetrofosmin Myocardial Perfusion Imaging in Ischemic Stroke.

Science.gov (United States)

Giannopoulos, Sotirios; Markoula, Sofia; Sioka, Chrissa; Zouroudi, Sofia; Spiliotopoulou, Maria; Naka, Katerina K; Michalis, Lampros K; Fotopoulos, Andreas; Kyritsis, Athanassios P

2017-10-01

To assess the myocardial status in patients with stroke, employing myocardial perfusion imaging (MPI) with 99m Technetium-tetrofosmin ( 99m Tc-TF)-single-photon emission computed tomography (SPECT). Fifty-two patients with ischemic stroke were subjected to 99m Tc-TF-SPECT MPI within 1 month after stroke occurrence. None of the patients had any history or symptoms of coronary artery disease or other heart disease. Myocardial perfusion imaging was evaluated visually using a 17-segment polar map. Myocardial ischemia (MIS) was defined as present when the summed stress score (SSS) was >4; MIS was defined as mild when SSS was 4 to 8, and moderate/severe with SSS ≥9. Patients with SSS >4 were compared to patients with SSS SSS >9 were compared to patients with SSS SSS, with the oldest age exhibiting the highest SSS ( P = .01). The association of age with SSS remained statistically significant in the multivariate analysis ( P = .04). The study suggested that more than half of patients with stroke without a history of cardiac disease have MIS. Although most of them have mild MIS, we suggest a thorough cardiological evaluation in this group of patients for future prevention of severe myocardial outcome.

Improvement of myocardial perfusion detected by 201Tl scintigraphy on cardiac rehabilitation for patients with coronary artery disease

International Nuclear Information System (INIS)

Li, Linxue; Nohara, Ryuji; Makita, Shigeru

1996-01-01

The effect of cardiac rehabilitation (mean 70±48 months) on myocardial perfusion was assessed using thallium-201 ( 201 Tl) exercise study in 63 patients with coronary artery disease (CAD). Subjects were those in a rehabilitation group (Rh=42) participating in supervised sports training two to three times per week and the control group (Ct=21) not taking active daily exercise. The interval between two 201 Tl SPECT studies was 19±16 months. After physical training, total duration of the exercise test increased from 443±112 to 536±121 seconds (+19%) in the Rh group, and from 484±129 to 432±115 seconds in the Ct group (-10.7%) (p 2 to 269.8±58 x 10 2 in the Rh group and decreased from 218.7±40 x 10 2 to 216.6±76 x 10 2 (p 201 Tl myocardial perfusion defect on exercise improved more in 54.8% (stress 59.5%, rest 35.7%) in the Rh group than in the Ct group (9.5%, p 201 Tl perfusion defect decreased from 68 (23.1%) to 49 regions (16.7%) of 294 total myocardial regions in the Rh group on exercise. However. it increased from 39 (26.5%) to 44 (29.9%) regions of 147 regions in the Ct group (p<0.01). Thus, cardiac rehabilitation increases exercise tolerance with improvement of myocardial perfusion. suggesting that cardiac rehabilitation is an advisable and effective treatment for patients with ischemic heart disease. (author)

[Hypertrophic cardiomyopathy showing no 123I-BMIPP myocardial accumulation with type I CD36 deficiency].

Science.gov (United States)

Watanabe, K; Miyajima, S; Kusano, Y; Tanabe, N; Hirokawa, Y

1997-07-01

A 57 years old male consulted our hospital in complaining chest oppression and short of breath. Familial and dilated phase hypertrophic cardiomyopathy (HCM) was detected by ECG, echocardiography, left ventriculography and left ventricular endomyocardial biopsy. 201T1 SPECT showed regional increased accumulation in the ventricular septum, however, no myocardial accumulation of 123I-beta-methyl-p-iodophenylpentadecanoic acid (123I-BMIPP) was observed. We analyzed CD36 in this patient, and found he had type 1 CD36 deficiency. Myocardial uptake of long-chain fatty acids occurs via a specific transporter, which is homologous with human CD36. We hypothesize that CD36 deficiency, especially type 1 CD36 deficiency, might be one factor of no myocardial 123I-BMIPP uptake.

The Influence of findings of coronary artery on myocardial salvage in acute myocardial infarction

International Nuclear Information System (INIS)

Itano, Midoriko; Naruse, Hitoshi; Morita, Masato; Kawamoto, Hideo; Yamamoto, Juro; Fukutake, Naoshige; Ohyanagi, Mitsumasa; Iwasaki, Tadaaki; Fukuchi, Minoru

1992-01-01

201 Tl stress myocardial scintigraphy was performed in convalescent patients with acute myocardial infarction, to evaluate the influence of stenosis and collateral circulation of coronary artery in acute phase, on myocardial salvage in chronic phase. In 14 cases of unsuccessful coronary revascularization (complete occlusion), a complete defect of thallium imaging in chronic phase was seen in only one case of four cases with good collateral circulation, while eight of 10 cases with poor collateral circulation. In 16 cases with collateral circulation, six cases showed a complete defect, although the target vessel had improved to less than 75% of stenosis. However, in cases of good collateral circulation, no case showed a complete defect when the target vessel had improved to less than 75% of stenosis. The myocardial salvage is quite possible (p<0.05), when the coronary angiography in acute phase showed the forward flow (99% or 90% of stenosis) before coronary revascularization and/or good collateral circulation (Rentrop 2deg or 3deg). (author)

Comparison between the summed difference score and myocardial blood flow measured by 13N-ammonia.

Science.gov (United States)

Giubbini, Raffaele; Peli, Alessia; Milan, Elisa; Sciagrà, Roberto; Camoni, Luca; Albano, Domenico; Bertoli, Mattia; Bonacina, Mattia; Motta, Federica; Statuto, Massimo; Rodella, Carlo Alberto; De Agostini, Antonio; Calabretta, Raffaella; Bertagna, Francesco

2017-02-03

Both the myocardial perfusion pattern and myocardial blood flow (MBF) are used to assess patients with suspected coronary artery disease (CAD). The aim of this study was to compare the perfusion pattern (using the summed difference score [SDS]) to MBF in a consecutive group of patients undergoing PET/CT with 13 N-ammonia ( 13 NH 3 ). 47 consecutive patients, aged 65 ± 12 years (42 men) with known or suspected CAD, underwent vasodilator stress/rest PET/CT with 13 NH 3 for clinical indications. The SDS was determined by a commercially available software based on a 17-segment model. MBF was measured at rest and during hyperemia by dynamic acquisition and single-compartment model analysis. From the rest and stress MBF, the absolute difference (stress-rest) in myocardial blood flow defined as difference in myocardial blood flow (DMBF) was derived. There were no significant differences between patients with no ischemia (SDS ≤ 1) and those with ischemia (SDS > 1) in CFR (2.84 ± 0.73 vs 2.63 ± 0.89, P = NS) and DMBF (1.34 ± 0.45 vs 1.24 ± 0.53 mL·minute -1 ·g -1 , P = NS). There were however significant regional differences (141 different vascular territories in 47 patients) between these two groups (CFR: 2.84 ± 0.95 vs 2.16 ± 0.57, P measurements (stress-rest) and it correlates better with regional DMBF, which is another measurement that reflects the difference between stress and rest. The correlation is better on regional than global basis.

Correlation between semiquantitative myocardial perfusion score and absolute myocardial flow in 13N-ammonia PET

International Nuclear Information System (INIS)

Lee, Byeong Il; Kim, Jung Young; Min, Jung Joon; Song, Ho Chun; Bom, Hee Seung; Kim, Kye Hun; Kim, Su Jin; Lee, Jae Sung

2007-01-01

13 N-ammonia is a well known radiopharmaceutical for the measurement of a myocardial blood flow (MBF) non-invasively using PET-CT. In this study, we investigated a correlation between MBF obtained from dynamic imaging and myocardial perfusion score (MPS) obtained from static imaging for usefulness of cardiac PET study. Twelve patients (11 males, 1 female, 57.9 ± 8.6 years old) with suspicious coronary artery disease underwent PET-CT scan. Dynamic scans (6 min: 5 sec X 12, 10 sec X 6, 20 sec X 3, and 30 sec X 6) were initiated simultaneously with bolus injection of 11 MBq/kg 13 N-ammonia to acquire rest and stress image. Gating image was acquired during 13 minutes continuously. Nine-segment model (4 basal walls, 4 mid walls, and apex) was used for a measurement of MBF. Time activity curve of input function and myocardium was extracted from ROI methods in 9 regions for quantification. The MPS were evaluated using quantitative analysis software. To compare between 20-segment model and 9-segment model, 6 basal segments were excluded and averaged segmental scores were used. There are weak correlation between MBF (rest, 0.18-2.38 ml/min/g; stress, 0.40-4.95 ml/min/g) and MPS (rest 22-91%, stress, 14-90%), however the correlation coefficient between corrected MBF and MPS in rest state was higher than stress state (rest r=0.59; stress r=0.80). As a thickening increased, correlation between MBF and MPS also showed good correlation at each segments. Corrected and translated MPS as its characteristics using 13 N-ammonia showed good correlation with absolute MBF measured by dynamic image in this study. Therefore, we showed MPS is one of good indices which reflect MBF. We anticipate PET-CT could be used as useful tool for evaluation of myocardial function in nuclear cardiac study

Characteristics of 201Tl myocardial SPECT and left ventriculography in patients with acute diagonal branch myocardial infarction

International Nuclear Information System (INIS)

Tanaka, Takeshi; Aizawa, Tadanori; Katou, Kazuzo; Ogasawara, Ken; Kirigaya, Hajime

1993-01-01

Characteristics of 201 Tl myocardial SPECT and ventriculography were studied in 13 patients with acute diagonal branch myocardial infarction. Rest 201 Tl myocardial SPECT and left ventriculography were underwent in chronic phase. In 5 patients electrocardiogram (ECG) changes in acute phase were not definite. In 6 patients it was difficult to identify the obstructed coronary artery with coronary angiography in acute phase. Mean value of maximum creatine phosphokinese (CPK) was 854 (458-1,774) U/l. It seemed to be difficult to diagnose acute diagonal branch myocardial infarction with ECG and/or coronary angiography. In all patients defects were noted on 201 Tl SPECT. Defects were small and noted in the central anterior wall and not in the septum. In 2 patients defects were noted at apex. In left ventriculography dyskinetic motion was noted in 10 patients; one patient showed apical aneurysm and 3 patients showed anterior wall aneurysm. In 3 patients anterior wall showed akinesis. It was concluded that 201 Tl myocardial SPECT were useful for detecting diagonal branch lesion. In case of diagonal branch myocardial infarction size of defects were small and defects were not noted in the septum, however aneurysmal motion was frequently noted. (author)

Gross anatomical study on the human myocardial bridges with special reference to the spatial relationship among coronary arteries, cardiac veins, and autonomic nerves.

Science.gov (United States)

Watanabe, Yuko; Arakawa, Takamitsu; Kageyama, Ikuo; Aizawa, Yukio; Kumaki, Katsuji; Miki, Akinori; Terashima, Toshio

2016-04-01

Coronary arteries are frequently covered by cardiac muscles. This arrangement is termed a myocardial bridge. Previous studies have shown that myocardial bridges can cause myocardial ischemic diseases or cardiac arrhythmia, but the relevant pathogenic mechanisms remain unknown. We examined 60 hearts from Japanese cadavers macroscopically to clarify the spatial relationships among coronary arteries, cardiac veins and autonomic nerves. We found 86 myocardial bridges in 47 hearts from the 60 cadavers examined (78.3%). Next, we dissected out nine hearts with myocardial bridges in detail under the operating microscope. We found no additional branches of coronary arteries on the myocardial bridge surfaces. However, the cardiac veins, which usually accompany the coronary arteries, ran independently on the myocardial bridge surfaces in the same region. Cardiac autonomic nerves comprised two rami: one was associated with the coronary artery under the myocardial bridge and the other ran on the surface of the bridge. Such spatial relationships among the coronary arteries, cardiac veins and cardiac autonomic nerves at the myocardial bridges are quite similar to those in mouse embryo hearts. © 2015 Wiley Periodicals, Inc.

Quantification of left ventricular regional functions using ECG-gated myocardial perfusion SPECT. Validation of left ventricular systolic functions

International Nuclear Information System (INIS)

Yamamoto, Akira; Takahashi, Naoto; Iwahara, Shin-ichiro; Munakata, Kazuo; Hosoya, Tetsuo

2006-01-01

We have developed a program to quantify regional left ventricular (LV) function and wall motion synchrony using electrocardiogram (ECG)-gated myocardial perfusion SPECT (MPS). This preliminary study was undertaken to validate the use of this program for estimating regional LV systolic function. Patients were subjected to MPS by 99m Tc-sestamibi at rest. The study included 20 patients who were confirmed to have a low probability of coronary artery disease (LPG; low probability group), 19 heart disease patients who were examined by MPS and equilibrium radionuclide angiography (ERNA) (ERG; ERNA group), and 24 patients who were examined by MPS and 2-dimensional echocardiography (2DE) (2DEG; 2DE group). The values of the ejection fraction (EF) and peak ejection rate (PER) were estimated. The global functions evaluated by this program were compared with those obtained by ERNA in the ERG. For regional assessment, the reference values of the functional indices were obtained for 17 LV segments in LPG. The Z score, (reference average value of the segment-patient's value of the segment)/reference standard deviation of the segment, was used for the evaluation of regional functions; a score equal to or greater than 2 was defined as abnormal. Semiquantitative visual interpretation of 2DE was used as the standard to assess wall motion. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of these criteria and the relationship between 2DE grading and Z scoring were validated in 2DEG. The values of the global EF and PER evaluated by this program correlated with those determined by ERNA (r=0.76 and 0.58, respectively; p -10 ). The potential of this program to quantify the regional systolic function was validated. (author)

A computer graphics based model for scattering from objects of arbitrary shapes in the optical region

Science.gov (United States)

Goel, Narendra S.; Rozehnal, Ivan; Thompson, Richard L.

1991-01-01

A computer-graphics-based model, named DIANA, is presented for generation of objects of arbitrary shape and for calculating bidirectional reflectances and scattering from them, in the visible and infrared region. The computer generation is based on a modified Lindenmayer system approach which makes it possible to generate objects of arbitrary shapes and to simulate their growth, dynamics, and movement. Rendering techniques are used to display an object on a computer screen with appropriate shading and shadowing and to calculate the scattering and reflectance from the object. The technique is illustrated with scattering from canopies of simulated corn plants.

Myocardial Perfusion: Characteristics of Distal Intramyocardial Arteriolar Trees.

Science.gov (United States)

Zamir, Mair; Vercnocke, Andrew J; Edwards, Phillip K; Anderson, Jill L; Jorgensen, Steven M; Ritman, Erik L

2015-11-01

A combination of experimental, theoretical, and imaging methodologies is used to examine the hierarchical structure and function of intramyocardial arteriolar trees in porcine hearts to provide a window onto a region of myocardial microvasculature which has been difficult to fully explore so far. A total of 66 microvascular trees from 6 isolated myocardial specimens were analyzed, with a cumulative number of 2438 arteriolar branches greater than or equal to 40 μm lumen diameter. The distribution of flow rates within each tree was derived from an assumed power law relationship for that tree between the diameter of vessel segments and flow rates that are consistent with that power law and subject to conservation of mass along hierarchical structure of the tree. The results indicate that the power law index increases at levels of arteriolar vasculature closer to the capillary level, consistent with a concomitant decrease in shear stress acting on endothelial tissue. These results resolve a long standing predicament which could not be resolved previously because of lack of data about the 3D, interconnected, arterioles. In the context of myocardial perfusion, the results indicate that the coefficient of variation of flow rate in pre-capillary distal arterioles is high, suggesting that heterogeneity of flow rate in these arterioles is not entirely random but may be due at least in part to active control.

Pharmacological radionuclide ventriculography for detection of myocardial contractile reserve in patients after myocardial infarction: head-to-head comparison of low dose dobutamine and low dose dypiridamole

International Nuclear Information System (INIS)

Petrasinovic, Z.; Ostojic, M.; Beleslin, B.; Stojkovic, S.; Nedeljkovic, M.; Stankovic, G.; Dikic, A.; Pavlovic, S.; Sobic, D.

2002-01-01

Background. Low dose pharmacological stress echocardiography with either dobutamine or dipyridamole infusion has been proposed for recognition of myocardial viability. However, dependence on adequate acoustic window, observer experience, and the mild degree of wall motion changes make the viability assessment by stress echocardiography especially bothersome. The objective of the study was to evaluate the ability of low dose dobutamine and low dose dipyridamole radionuclide ventriculography to detect contractile reserve in patients after myocardial infarction and functional recovery after coronary angioplasty. Methods. The study group consisted of 20 consecutive patients (52±10 years, 17 male) with previous myocardial infarction and resting regional dyssynergy, in whom diagnostic cardiac catheterization revealed significant one-vessel coronary artery stenosis suitable for angioplasty. Each patient underwent equilibrium 99m-Tc radionuclide ventriculography which was performed at rest and during low dose dipyridamole (0.28 mg/kg over 2 minutes) and low dose dobutamine infusion (up to 10 mcg/kg/min). Left ventricular global and regional ejection fractions were determined. Increase of regional ejection fraction for >5% (inferoapical and posterolateral regions) or >10% (anteroseptal regions) during low dose dobutamine and dipyridamole in infarcted regions, as well as in the follow up period, was considered as index of contractile reserve. After 8 weeks of successful angioplasty, resting radionuclide ventriculography was repeated in all patients in order to identify functional recovery of the infarct zone. Results. Out of the 180 analyzed segments (20x9), 90 regional ejection fractions have shown depressed contractility. The mean of the regional ejection fractions showing depressed contractility increased from the resting value of 34±12% to 42±14% in the follow-up period (p=0.06). Of the 90 with baseline dyssynergy, 46 were responders during low-dose dobutamine (51

Fundamental and clinical evaluation of Fourier analysis for the detection of regional wall contraction abnormalities in the patients with myocardial infarction

International Nuclear Information System (INIS)

Murata, H.; Toyama, H.; Tabuchi, H.; Muraki, T.; Ohtake, E.; Chiba, K.; Yamada, H.

1982-01-01

The purpose of the present study are to evaluate fundamentally the method of Fourier analysis and to detect regional wall motion abnormality of the infarcted lesions by Fourier analysis. Fourier analyses were performed using the data obtained by first pass method in right anterior oblique projection (RAO) and by equilibrium method in left anterior oblique projection (LAO), and amplitude and phase were calculated. Amplitude and phase values needed to be corrected by R-R interval. On the detection of myocardial infarction, Fourier analyses in RAO and in LAO had same value for anterior infarctions. The analysis in RAO was more sensitive to detect infero-posterior lesions. On the other hand, the analysis in LAO was more sensitive for septal and lateral lesions

Morphological aspects of myocardial bridges.

Science.gov (United States)

Lujinović, Almira; Kulenović, Amela; Kapur, Eldan; Gojak, Refet

2013-11-01

Although some myocardial bridges can be asymptomatic, their presence often causes coronary disease either through direct compression of the "tunnel" segment or through stimulation and accelerated development of atherosclerosis in the segment proximally to the myocardial bridge. The studied material contained 30 human hearts received from the Department of Anatomy. The hearts were preserved 3 to 5 days in 10% formalin solution. Thereafter, the fatty tissue was removed and arterial blood vessels prepared by careful dissection with special reference to the presence of the myocardial bridges. Length and thickness of the bridges were measured by the precise electronic caliper. The angle between the myocardial bridge fibre axis and other axis of the crossed blood vessel was measured by a goniometer. The presence of the bridges was confirmed in 53.33% of the researched material, most frequently (43.33%) above the anterior interventricular branch. The mean length of the bridges was 14.64 ± 9.03 mm and the mean thickness was 1.23 ± 1.32 mm. Myocardial bridge fibres pass over the descending blood vessel at the angle of 10-90 degrees. The results obtained on a limited sample suggest that the muscular index of myocardial bridge is the highest for bridges located on RIA, but that the difference is not significant in relation to bridges located on other branches. The results obtained suggest that bridges located on other branches, not only those on RIA, could have a great contractive power and, consequently, a great compressive force, which would be exerted on the wall of a crossed blood vessel.

Milrinone and levosimendan during porcine myocardial ischemia -- no effects on calcium overload and metabolism.

Science.gov (United States)

Axelsson, B; Johansson, G; Abrahamsson, P; Gupta, A; Tydén, H; Wouters, P; Haney, M

2013-07-01

Although inotropic stimulation is considered harmful in the presence of myocardial ischaemia, both calcium sensitisers and phosphodiesterase inhibitors may offer cardioprotection. We hypothesise that these cardioprotective effects are related to an acute alteration of myocardial metabolism. We studied in vivo effects of milrinone and levosimendan on calcium overload and ischaemic markers using left ventricular microdialysis in pigs with acute myocardial ischaemia. Anaesthetised juvenile pigs, average weight 36 kg, were randomised to one of three intravenous treatment groups: milrinone 50 μg/kg bolus plus infusion 0.5 μg/kg/min (n = 7), levosimendan 24 μg/kg plus infusion 0.2 μg/kg/min (n = 7), or placebo (n = 6) for 60 min prior to and during a 45 min acute regional coronary occlusion. Systemic and myocardial haemodynamics were assessed, and microdialysis was performed with catheters positioned in the left ventricular wall. (45) Ca(2+) was included in the microperfusate in order to assess local calcium uptake into myocardial cells. The microdialysate was analysed for glucose, lactate, pyruvate, glycerol, and for (45) Ca(2+) recovery. During ischaemia, there were no differences in microdialysate-measured parameters between control animals and milrinone- or levosimendan-treated groups. In the pre-ischaemic period, arterial blood pressure decreased in all groups while myocardial oxygen consumption remained stable. These findings reject the hypothesis of an immediate energy-conserving effect of milrinone and levosimendan during acute myocardial ischaemia. On the other hand, the data show that inotropic support with milrinone and levosimendan does not worsen the metabolic parameters that were measured in the ischaemic myocardium. © 2013 The Acta Anaesthesiologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

THE FORMATION OF AN INVERSE S-SHAPED ACTIVE-REGION FILAMENT DRIVEN BY SUNSPOT MOTION AND MAGNETIC RECONNECTION

Energy Technology Data Exchange (ETDEWEB)

Yan, X. L.; Xue, Z. K.; Wang, J. C.; Yang, L. H. [Yunnan Observatories, Chinese Academy of Sciences, Kunming 650011 (China); Priest, E. R. [Mathematics Institute, University of St Andrews, St Andrews, KY16 9SS (United Kingdom); Guo, Q. L., E-mail: yanxl@ynao.ac.cn [College of Mathematics Physics and Information Engineering, Jiaxing University, Jiaxing 314001 (China)

2016-11-20

We present a detailed study of the formation of an inverse S-shaped filament prior to its eruption in active region NOAA 11884 from 2013 October 31 to November 2. In the initial stage, clockwise rotation of a small positive sunspot around the main negative trailing sunspot formed a curved filament. Then the small sunspot cancelled with the negative magnetic flux to create a longer active-region filament with an inverse S-shape. At the cancellation site a brightening was observed in UV and EUV images and bright material was transferred to the filament. Later the filament erupted after cancellation of two opposite polarities below the upper part of the filament. Nonlinear force-free field extrapolation of vector photospheric fields suggests that the filament may have a twisted structure, but this cannot be confirmed from the current observations.

Quantitative myocardial thallium single-photon emission computed tomography in normal women: demonstration of age-related differences

International Nuclear Information System (INIS)

Cohen, M.; Touzery, C.; Cottin, Y.; Benoit, T.; Athis, P. d'; Roy, S.; Louis, P.; Wolf, J.E.; Rigo, P.; Brunotte, F.

1996-01-01

The aim of this study is the development of a database of normal women for quantitative analysis of exercise and reinjection myocardial single-photon emission computed tomography (SPET). We studied 101 subjects (40 males and 61 females) with less than 5% likelihood of coronary artery disease. All patients underwent stress and rest thallium-201 myocardial SPET. Myocardial stress was induced by bicycle exercise test (n=51), dipyridamole infusion (n=27) or a combined test (n=23). Multivariate ANOVA showed that the type of stress did not influence the percentage of thallium uptake for each region. Significant differences between men and women were found for the percentage of uptake in the inferior and the anterior wall. The most original finding of this study is the correlation between age and thallium uptake in the three regions of the anterior wall, showing an increase in measured thallium uptake with age for women. Consequently, two groups of women, those under and those over 55 years old, were separated, with a significantly lower tracer uptake in the anterior wall in the younger age group. (orig./MG)

Prognostic impact of physical activity prior to myocardial infarction

DEFF Research Database (Denmark)

Ejlersen, Hanne; Andersen, Zorana Jovanovic; von Euler-Chelpin, My Catarina

2017-01-01

the course of myocardial infarction by reducing case fatality and the subsequent risk of heart failure and mortality. Methods: A total of 14,223 participants in the Copenhagen City Heart Study were assessed at baseline in 1976-1978; 1,664 later developed myocardial infarction (mean age at myocardial...... estimated by logistic and Cox proportional hazards regression models, adjusted for age at myocardial infarction and other potential confounders. Results: A total of 425 (25.5%) myocardial infarctions were fatal. Higher levels of LTPA prior to myocardial infarction were associated with lower case fatality...

Clinical usefulness of 123I-labeled 15-iodophenyl 3-methyl pentadecanoic acid (BMIPP) myocardial SPECT in coronary artery disease

International Nuclear Information System (INIS)

Ito, Kazuki

1998-01-01

123 I-BMIPP (BMIPP) myocardial SPECT was carried out in 22 patients with acute myocardial infarction, in 20 patients with unstable angina pectoris, in 80 patients with effort angina pectoris and in 25 patients with vasospastic angina pectoris. In a study of patients with acute myocardial infarction, BMIPP uptake was less than thallium perfusion in areas of myocardial infarction. Such discordant BMIPP/thallium uptake was often observed in areas with recanalized arteries, and in those with abnormal wall motion. In the areas showing discordant BMIPP/thallium uptake, the wall motion abnormalities improved in the chronic phase after recanalization therapy. Therefore, the discordant BMIPP/thallium uptake might represent asynergic but viable regions, and might be valuable in predicting the improvement of wall motion abnormalities. In a study of patients with unstable angina pectoris, the severity of regional wall motion abnormality was significantly correlated with severity of BMIPP uptake. BMIPP imaging well visualized the culprit regions in patients with unstable angina pectoris. In a study of patients with effort angina pectoris, the abnormal BMIPP images were associated with severe coronary artery stenosis of more than 90% and with multivessel stenosis. BMIPP imaging could detect patients with functionally severe coronary artery disease and help to guide coronary angioplasty in patients with effort angina. In a study of patients with vasospastic angina pectoris, metabolic abnormality assessed by BMIPP was associated with left ventricular asynergy and spastic regions. Those abnormalities also correlated inversely with the period from the last attack, and improved after medical treatment. (K.H.)

Nuclear Charge Radii in the Region of Shape Isomerism at Z $\\leq$ 80

CERN Multimedia

2002-01-01

The determination of isotope shifts in the isotopic chain of Hg has led to quite a number of unexpected observations as the transition from slightly oblate to strongly prolate deformation below A~=~186, the shape coexistence in |1|8|5Hg and a huge odd-even staggering of the charge radii in the region 181~@$<$~ Until now it is quite open if the observed instability of the nuclear shape is an isolated and unique feature of the light Hg isotopes and how it changes with Z and depends on the shell and pairing energies.\\\\ \\\\ Therefore we propose to carry out a study of the isotope shifts in the neighbouring isotopes of the elements Au and Pt which can be obtained at ISOLDE as daughters of a primary Hg beam. Resonance ionization spectroscopy will be applied as a novel technique at ISOLDE. The time of flight of the photo ionized Au (or Pt) isotope in a drift tube will be used to get rid of any background events.

Imaging techniques for myocardial inflammation

International Nuclear Information System (INIS)

O'Connell, J.B.; Henkin, R.E.; Robinson, J.A.

1986-01-01

Dilated cardiomyopathy (DC) represents a heterogeneous group of disorders which results in morbidity and mortality in young individuals. Recent evidence suggests that a subset of these patients have histologic evidence of myocarditis which is potentially treatable with immunosuppression. The identification of myocardial inflammation may therefore lead to development of therapeutic regimens designed to treat the cause rather than the effect of the myocardial disease. Ultimately, this may result in improvement in the abysmal prognosis of DC. The currently accepted technique for identification of active myocardial inflammation is endomyocardial biopsy. This technique is not perfect, however, since pathologic standards for the diagnosis of myocarditis have not been established. Furthermore, focal inflammation may give rise to sampling error. The inflammation-avid radioisotope gallium-67 citrate has been used as an adjunct to biopsy improving the yield of myocarditis from 7 percent to 36 percent. Serial imaging correlates well to biopsy results. Future studies are designed to study the applicability of lymphocyte labelling techniques to myocardial inflammatory disease

Selective Cerebro-Myocardial Perfusion in Complex Neonatal Aortic Arch Pathology: Midterm Results.

Science.gov (United States)

Hoxha, Stiljan; Abbasciano, Riccardo Giuseppe; Sandrini, Camilla; Rossetti, Lucia; Menon, Tiziano; Barozzi, Luca; Linardi, Daniele; Rungatscher, Alessio; Faggian, Giuseppe; Luciani, Giovanni Battista

2018-04-01

Aortic arch repair in newborns and infants has traditionally been accomplished using a period of deep hypothermic circulatory arrest. To reduce neurologic and cardiac dysfunction related to circulatory arrest and myocardial ischemia during complex aortic arch surgery, an alternative and novel strategy for cerebro-myocardial protection was recently developed, where regional low-flow perfusion is combined with controlled and independent coronary perfusion. The aim of the present retrospective study was to assess short-term and mid-term results of selective and independent cerebro-myocardial perfusion in neonatal aortic arch surgery. From April 2008 to August 2015, 28 consecutive neonates underwent aortic arch surgery under cerebro-myocardial perfusion. There were 17 male and 11 female, with median age of 15 days (3-30 days) and median body weight of 3 kg (1.6-4.2 kg), 9 (32%) of whom with low body weight (cerebro-myocardial perfusion was 30 ± 11 min (15-69 min). Renal dysfunction, requiring a period of peritoneal dialysis was observed in 10 (36%) patients, while liver dysfunction was noted only in 3 (11%). There were three (11%) early and two late deaths during a median follow-up of 2.9 years (range 6 months-7.7 years), with an actuarial survival of 82% at 7 years. At latest follow-up, no patient showed signs of cardiac or neurologic dysfunction. The present experience shows that a strategy of selective and independent cerebro-myocardial perfusion is safe, versatile, and feasible in high-risk neonates with complex congenital arch pathology. Encouraging outcomes were noted in terms of cardiac and neurological function, with limited end-organ morbidity. © 2018 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

123I-meta-iodo-benzyl-guanidine myocardial scintigraphy and congestive heart failure: current data and perspective

International Nuclear Information System (INIS)

Agostini, D.; Darlas, Y.; Quennelle, F.; Bouvard, G.; Scanu, P.; Grollier, G.; Potier, J.C.; Babatasi, G.; Belin, A.

1997-01-01

Congestive heart failure is often associated with an impairment of the sympathetic nervous system, i.e., global hyperactivity and regional impairment of the adrenergic system. Cardiac 123 I-MIBG scintigraphy is a radionuclide technique which can explore the presynaptic adrenergic function. Myocardial MIBG fixation is decreased in congestive heart failure, reflecting a reduction of norepinephrine uptake by the myocardial presynaptic nerve endings. The impairment of presynaptic function occurs early in the disease and is actually involved in the pathogenesis of cardiac failure. Cardiac MIBG scintigraphy is a useful tool to explore the myocardial adrenergic stores in patients with congestive heart failure. It could be proposed in patients with severe ventricular dysfunction in order to assist physicians in setting-up the timing of heart transplantation. (authors)

Myocardial capillary permeability for small hydrophilic indicators during normal physiological conditions and after ischemia and reperfusion

DEFF Research Database (Denmark)

Svendsen, Jesper Hastrup

1991-01-01

Myocardial capillary permeability for small hydrophilic solutes (51Cr-EDTA or 99mTc-DTPA) has been measured using intracoronary indicator bolus injection and external radioactivity registration (the single injection, residue detection method). The method is based on kinetic separation of the inje......Myocardial capillary permeability for small hydrophilic solutes (51Cr-EDTA or 99mTc-DTPA) has been measured using intracoronary indicator bolus injection and external radioactivity registration (the single injection, residue detection method). The method is based on kinetic separation...... including microvascular alterations. In open chest dogs transitory increases in capillary extraction fraction and PdS for small hydrophilic solutes were seen following 20 minutes of regional myocardial ischemia and reperfusion. This response could be inhibited by treatment directed against superoxide...

Comparison between unstable angina pectoris and stable effort angina pectoris by using 123I-BMIPP and 201Tl myocardial SPECT

International Nuclear Information System (INIS)

Hisatake, Shinji; Yamashina, Shohei; Yamazaki, Junichi

2004-01-01

We performed BMIPP myocardial SPECT and Tl myocardial SPECT in patients with unstable angina (UAP) and stable effort angina (SAP), and compared the results for the two groups. Our subjects were 30 patients with the UAP and 25 patients with the SAP. The early and delayed images of the BMIPP were obtained with patients at rest. The early image of the Tl alone was obtained with patients at rest. We calculated severity score (SS) using the polar map based on SPECT short-axis image on the both myocardial SPECT. And, we calculated % uptake of the responsible coronary lesion and regional washout rate (WR) on myocardial SPECT with BMIPP. On coronary angiogram, no difference in % diameter stenosis was seen between the two groups. On myocardial SPECT with Tl, no difference in the SS was seen between the two groups. However, on myocardial SPECT with BMIPP, the SS was significantly higher score in the UAP group than in the SAP group. And, on myocardial SPECT with BMIPP, the % uptake and the WR were significant lower values in the UAP group than in the SAP group. Even if the two groups have almost the same level of myocardial perfusion disorder, the UAP group may have severer myocardial fatty-acid metabolic disorder than the SAP group, because the defects in BMIPP were significantly severer in the UAP group. (author)

Sodium bicarbonate-augmented stress thallium myocardial scintigraphy

International Nuclear Information System (INIS)

Sarin, Badal; Chugh, Pradeep Kumar; Kaushal, Dinesh; Soni, Nakse Lal; Sawroop, Kishan; Mondal, Anupam; Bhatnagar, Aseem

2004-01-01

It is well known that sodium bicarbonate in pharmacological doses induces transient alkalosis, causing intracellular transport of serum potassium. The aims of this study were (a) to investigate whether, in humans, myocardial thallium-201 uptake can be augmented by pretreatment with a single bolus of sodium bicarbonate at a pharmacological dose, (b) to verify general safety aspects of the intervention and (c) to evaluate the clinical implications of augmentation of 201 Tl uptake, if any. Routine exercise myocardial scintigraphy was performed twice in eight adult volunteers (five normal and three abnormal), once without intervention and the second time (within a week) following intravenous administration of sodium bicarbonate (88 mEq in 50 ml) as a slow bolus 1 h prior to the injection of 201 Tl. Conventional myocardial thallium study was compared with sodium bicarbonate interventional myocardial scintigraphy with respect to myocardial uptake (counts per minute per mCi injected dose), washout patterns in normal and abnormal myocardial segments, and overall clinical interpretation based on planar and single-photon emission tomographic (SPET) images. All patients remained asymptomatic after the intervention. A mean increase of 53% in myocardial uptake of thallium was noted in post-exercise acquisitions after the intervention, confirming uptake of the tracer via the potassium-hydrogen pump and its augmentation by transient alkalosis. The washout pattern remained unchanged. The visual quality of planar and SPET images improved significantly after the intervention. Out of the five abnormal myocardial segments identified in three cases, four showed significant filling-in after the intervention, causing the diagnosis to be upgraded from ''partial scar'' to ''ischaemia'', or from ''ischaemia'' to ''normal''. The overall scan impression changed in two out of three such cases. Sodium bicarbonate augmentation may have significant implications for stress-thallium scintigraphy

Effect of eating on thallium myocardial imaging

International Nuclear Information System (INIS)

Wilson, R.A.; Sullivan, P.J.; Okada, R.D.; Boucher, C.A.; Morris, C.; Pohost, G.M.; Strauss, H.W.

1986-01-01

To determine if eating between initial and delayed thallium images alters the appearance of the delayed thallium scan, a prospective study was performed; 184 subjects sent for routine thallium imaging were randomized into two groups, those who ate a meal high in carbohydrates between initial and delayed thallium myocardial images (n = 106), and those who fasted (n = 78). The 201 Tl images were interpreted in blinded fashion for global myocardial and pulmonary clearance of 201 Tl myocardial defects. The eating group had a significantly lower incidence of transient myocardial defects compared to the noneating group (7 percent vs 18 percent, respectively; p less than 0.05). The time between initial and delayed images and the incidence of exercise-induced ischemic ST-segment depression or pathologic Q waves on the electrocardiogram were not significantly different between the two groups. These data suggest that eating a high-carbohydrate meal between initial and delayed 201 Tl images causes increased 201 Tl myocardial clearance rates and may alter 201 Tl myocardial redistribution over time

Noninvasive assessment of canine myocardial oxidative metabolism with carbon-11 acetate and positron emission tomography

International Nuclear Information System (INIS)

Brown, M.A.; Myears, D.W.; Bergmann, S.R.

1988-01-01

Noninvasive quantification of regional myocardial metabolism would be highly desirable to evaluate pathogenetic mechanisms of heart disease and their response to therapy. It was previously demonstrated that the metabolism of radiolabeled acetate, a readily utilized myocardial substrate predominantly metabolized to carbon dioxide (CO2) by way of the tricarboxylic acid cycle, provides a good index of oxidative metabolism in isolated perfused rabbit hearts because of tight coupling between the tricarboxylic acid cycle and oxidative phosphorylation. In the present study, in a prelude to human studies, the relation between myocardial clearance of carbon-11 (11C)-labeled acetate and myocardial oxygen consumption was characterized in eight intact dogs using positron emission tomography. Anesthetized dogs were studied during baseline conditions and again during either high or low work states induced pharmacologically. High myocardial extraction and rapid blood clearance of tracer yielded myocardial images of excellent quality. The turnover (clearance) of 11C radioactivity from the myocardium was biexponential with the mean half-time of the dominant rapid phase averaging 5.4 +/- 2.2, 2.8 +/- 1.3 and 11.1 +/- 1.3 min in control, high and low work load studies, respectively. No significant difference was found between the rate of clearance of 11C radioactivity from the myocardium measured noninvasively with positron emission tomography and the myocardial efflux of 11CO2 measured directly from the coronary sinus. The rate of clearance of the 11C radioactivity from the heart correlated closely with myocardial oxygen consumption (r = 0.90, p less than 0.001) as well as with the rate-pressure product (r = 0.95, p less than 0.001). Hence, the rate of oxidation of 11C-acetate can be determined noninvasively with positron emission tomography, providing a quantitative index of oxidative metabolism under diverse conditions

SPECT myocardial blood flow quantitation toward clinical use: a comparative study with {sup 13}N-Ammonia PET myocardial blood flow quantitation

Energy Technology Data Exchange (ETDEWEB)

Hsu, Bailing [University of Missouri-Columbia, Nuclear Science and Engineering Institute, Columbia, Missouri (United States); Hu, Lien-Hsin; Yang, Bang-Hung; Ting, Chien-Hsin; Huang, Wen-Sheng [Taipei Veterans General Hospital, Department of Nuclear Medicine, Taipei (China); Chen, Lung-Ching [Shin Kong Wu-Ho Su Memorial Hospital, Division of Cardiology, Taipei (China); Chen, Yen-Kung [Shin Kong Wu-Ho Su Memorial Hospital, Department of Nuclear Medicine, Taipei (China); Hung, Guang-Uei [Chang Bing Show Chwan Memorial Hospital, Department of Nuclear Medicine, Changhua (China); Wu, Tao-Cheng [National Yang-Ming University, Cardiovascular Research Center, Taipei (China)

2017-01-15

The aim of this study was to evaluate the accuracy of myocardial blood flow (MBF) quantitation of {sup 99m}Tc-Sestamibi (MIBI) single photon emission computed tomography (SPECT) compared with {sup 13}N-Ammonia (NH3) position emission tomography (PET) on the same cohorts. Recent advances of SPECT technologies have been applied to develop MBF quantitation as a promising tool to diagnose coronary artery disease (CAD) for areas where PET MBF quantitation is not available. However, whether the SPECT approach can achieve the same level of accuracy as the PET approach for clinical use still needs further investigations. Twelve healthy volunteers (HVT) and 16 clinical patients with CAD received both MIBI SPECT and NH3 PET flow scans. Dynamic SPECT images acquired with high temporary resolution were fully corrected for physical factors and processed to quantify K1 using the standard compartmental modeling. Human MIBI tracer extraction fraction (EF) was determined by comparing MIBI K1 and NH3 flow on the HVT group and then used to convert flow values from K1 for all subjects. MIBI and NH3 flow values were systematically compared to validate the SPECT approach. The human MIBI EF was determined as [1.0-0.816*exp(-0.267/MBF)]. Global and regional MBF and myocardial flow reserve (MFR) of MIBI SPECT and NH3 PET were highly correlated for all subjects (global R{sup 2}: MBF = 0.92, MFR = 0.78; regional R{sup 2}: MBF ≥ 0.88, MFR ≥ 0.71). No significant differences for rest flow, stress flow, and MFR between these two approaches were observed (All p ≥ 0.088). Bland-Altman plots overall revealed small bias between MIBI SPECT and NH3 PET (global: ΔMBF = -0.03Lml/min/g, ΔMFR = 0.07; regional: ΔMBF = -0.07 - 0.06, ΔMFR = -0.02 - 0.22). Quantitation with SPECT technologies can be accurate to measure myocardial blood flow as PET quantitation while comprehensive imaging factors of SPECT to derive the variability between these two approaches were fully addressed and corrected

SPECT myocardial blood flow quantitation toward clinical use: a comparative study with "1"3N-Ammonia PET myocardial blood flow quantitation

International Nuclear Information System (INIS)

Hsu, Bailing; Hu, Lien-Hsin; Yang, Bang-Hung; Ting, Chien-Hsin; Huang, Wen-Sheng; Chen, Lung-Ching; Chen, Yen-Kung; Hung, Guang-Uei; Wu, Tao-Cheng

2017-01-01

The aim of this study was to evaluate the accuracy of myocardial blood flow (MBF) quantitation of "9"9"mTc-Sestamibi (MIBI) single photon emission computed tomography (SPECT) compared with "1"3N-Ammonia (NH3) position emission tomography (PET) on the same cohorts. Recent advances of SPECT technologies have been applied to develop MBF quantitation as a promising tool to diagnose coronary artery disease (CAD) for areas where PET MBF quantitation is not available. However, whether the SPECT approach can achieve the same level of accuracy as the PET approach for clinical use still needs further investigations. Twelve healthy volunteers (HVT) and 16 clinical patients with CAD received both MIBI SPECT and NH3 PET flow scans. Dynamic SPECT images acquired with high temporary resolution were fully corrected for physical factors and processed to quantify K1 using the standard compartmental modeling. Human MIBI tracer extraction fraction (EF) was determined by comparing MIBI K1 and NH3 flow on the HVT group and then used to convert flow values from K1 for all subjects. MIBI and NH3 flow values were systematically compared to validate the SPECT approach. The human MIBI EF was determined as [1.0-0.816*exp(-0.267/MBF)]. Global and regional MBF and myocardial flow reserve (MFR) of MIBI SPECT and NH3 PET were highly correlated for all subjects (global R"2: MBF = 0.92, MFR = 0.78; regional R"2: MBF ≥ 0.88, MFR ≥ 0.71). No significant differences for rest flow, stress flow, and MFR between these two approaches were observed (All p ≥ 0.088). Bland-Altman plots overall revealed small bias between MIBI SPECT and NH3 PET (global: ΔMBF = -0.03Lml/min/g, ΔMFR = 0.07; regional: ΔMBF = -0.07 - 0.06, ΔMFR = -0.02 - 0.22). Quantitation with SPECT technologies can be accurate to measure myocardial blood flow as PET quantitation while comprehensive imaging factors of SPECT to derive the variability between these two approaches were fully addressed and corrected. (orig.)

Comparison with myocardial perfusion MRI and myocardial perfusion SPECT in the diagnostic performance of coronary artery disease. A meta-analysis

International Nuclear Information System (INIS)

Iwata, Kunihiro; Kubota, Makoto; Ogasawara, Katsuhiko

2008-01-01

We compared the diagnostic abilities of stress myocardial perfusion MRI (myocardial perfusion MRI) and myocardial perfusion single photon emission computed tomography (SPECT), using a meta-analysis method. We investigated the diagnostic abilities of MRI and SPECT in similar subject groups in reports written in English or Japanese. The reports to be used for analysis were selected according to a ''screening standard,'' which was established in advance. After consolidating the data from the selected reports, we compared the integrated odds ratio, the point estimation values of sensibility/specificity, and the summary receiver operating characteristic (ROC) curve. For the analysis, six reports were selected (subjects: 153, coronary-artery target sites: 447). Meta-analysis revealed that the diagnostic ability of myocardial perfusion MRI was superior to that of myocardial perfusion SPECT regarding each of the parameters. This is considered to be supportive evidence of the usefulness of myocardial perfusion MRI. (author)

Evaluation of left ventricular function using electrocardiographically gated myocardial SPECT with (123)I-labeled fatty acid analog.

Science.gov (United States)

Nanasato, M; Ando, A; Isobe, S; Nonokawa, M; Hirayama, H; Tsuboi, N; Ito, T; Hirai, M; Yokota, M; Saito, H

2001-12-01

Electrocardiographically (ECG) gated myocardial SPECT with (99m)Tc-tetrofosmin has been used widely to assess left ventricular (LV) function. However, the accuracy of variables using ECG gated myocardial SPECT with beta-methyl-p-(123)I-iodophenylpentadecanoic acid (BMIPP) has not been well defined. Thirty-six patients (29 men, 7 women; mean age, 61.6 +/- 15.6 y) with ischemic heart disease underwent ECG gated myocardial SPECT with (123)I-BMIPP and with (99m)Tc-tetrofosmin and left ventriculography (LVG) within 1 wk. LV ejection fraction (LVEF), LV end-diastolic volume (LVEDV), and LV end-systolic volume (LVESV) were determined on gated SPECT using commercially available software for automatic data analysis. These volume-related items on LVG were calculated with an area-length method and were estimated by 2 independent observers to evaluate interobserver validity. The regional wall motion with these methods was assessed visually. LVEF was 41.1% +/- 12.5% on gated SPECT with (123)I-BMIPP, 44.5% +/- 13.1% on gated SPECT with (99m)Tc-tetrofosmin, and 46.0% +/- 12.7% on LVG. Global LV function and regional wall motion between both gated SPECT procedures had excellent correlation (LVEF, r = 0.943; LVEDV, r = 0.934; LVESV, r = 0.952; regional wall motion, kappa = 0.92). However, the correlations of global LV function and regional wall motion between each gated SPECT and LVG were significantly lower. Gated SPECT with (123)I-BMIPP showed the same interobserver validity as gated SPECT with (99m)Tc-tetrofosmin. Gated SPECT with (123)I-BMIPP provides high accuracy with regard to LV function and is sufficiently applicable for use in clinical SPECT. This technique can simultaneously reveal myocardial fatty acid metabolism and LV function, which may be useful to evaluate various cardiac diseases.

Cardiorespiratory fitness modifies the relationship between myocardial function and cerebral blood flow in older adults.

Science.gov (United States)

Johnson, Nathan F; Gold, Brian T; Bailey, Alison L; Clasey, Jody L; Hakun, Jonathan G; White, Matthew; Long, Doug E; Powell, David K

2016-05-01

A growing body of evidence indicates that cardiorespiratory fitness attenuates some age-related cerebral declines. However, little is known about the role that myocardial function plays in this relationship. Brain regions with high resting metabolic rates, such as the default mode network (DMN), may be especially vulnerable to age-related declines in myocardial functions affecting cerebral blood flow (CBF). This study explored the relationship between a measure of myocardial mechanics, global longitudinal strain (GLS), and CBF to the DMN. In addition, we explored how cardiorespiratory affects this relationship. Participants were 30 older adults between the ages of 59 and 69 (mean age=63.73years, SD=2.8). Results indicated that superior cardiorespiratory fitness and myocardial mechanics were positively associated with DMN CBF. Moreover, results of a mediation analysis revealed that the relationship between GLS and DMN CBF was accounted for by individual differences in fitness. Findings suggest that benefits of healthy heart function to brain function are modified by fitness. Copyright © 2015 Elsevier Inc. All rights reserved.

Evaluation of myocardial perfusion reserve in patients with CAD using Contrast-Enhanced MRI: A comparison between semiquantitative and quantitative methods

International Nuclear Information System (INIS)

Schmitt, M.; Mohrs, O.K.; Petersen, S.E.; Kreitner, K.F.

2002-01-01

Objective: Comparison between two semiquantitative methods and a quantitative evaluation of myocardial blood flow (MBF) for assessment of myocardial perfusion reserve (MPR) in patients with CAD. Material and Methods: 9 patients with coronary stenoses>50% were examined with an ECG-gated Saturation Recovery Turbo FLASH sequence by using Gd-DTPA as contrast agent (CA). The entive measurements were performed both during rest and hyperemia induced by adenosine. The up-slopes of the signal-time S(t) curves in the myocardium and left ventricular (LV) cavity were evaluated by a linear fit. MPR was calculated from the original up-slopes of the myocardial S(t) curves and from the up-slopes, which were normalized to the up-slopes of the LV S(t) curves, respectively. For quantification of MBF values, the mathematical model MMID 4 was used and MPR was evaluated from the MBF values. Results: With all tested methods, MPR was reduced in myocardial regions subtended by arteries with stenoses≥70% compared with remote regions. With MMID 4 and the normalized up-slope method, differences between severe ischemic and remote regions were statistically significant. Conclusion: The up-slope method with normalization and quantification with MMID 4 are more sensitive methods to differentiate between remote and ischemic myocardium than the up-slope method without normalization. (orig.) [de

NNLO corrections to anti B {yields} X{sub u}l anti {nu} in the shape-function region

Energy Technology Data Exchange (ETDEWEB)

Asatrian, H.M. [Erevanskij Fizicheskij Inst., Erevan (Armenia); Greub, C. [Bern Univ. (Switzerland). Inst. for Theoretical Physics; Pecjak, B.D. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

2008-10-15

The inclusive decay anti B {yields} X{sub u}l anti {nu} is of much interest because of its potential to constrain the CKM element vertical stroke V{sub ub} vertical stroke. Experimental cuts required to suppress charm background restrict measurements of this decay to the shape-function region, where the hadronic final state carries a large energy but only a moderate invariant mass. In this kinematic region, the differential decay distributions satisfy a factorization formula of the form H.J x S, where S is the non-perturbative shape function, and the object H.J is a perturbatively calculable hard-scattering kernel. In this paper we present the calculation of the hard function H at next-to-next-to-leading order (NNLO) in perturbation theory. Combined with the known NNLO result for the jet function J, this completes the perturbative part of the NNLO calculation for this process. (orig.)

Regional Longitudinal Deformation Improves Prediction of Ventricular Tachyarrhythmias in Patients With Heart Failure With Reduced Ejection Fraction

DEFF Research Database (Denmark)

Biering-Sørensen, Tor; Knappe, Dorit; Pouleur, Anne-Catherine

2017-01-01

BACKGROUND: Left ventricular dysfunction is a known predictor of ventricular arrhythmias. We hypothesized that measures of regional longitudinal deformation by speckle-tracking echocardiography predict ventricular tachyarrhythmias and provide incremental prognostic information over clinical...... in the model, only a decreasing myocardial function in the inferior myocardial wall predicted VT/VF (hazard ratio, 1.05 [1.00-1.11]; P=0.039). Only strain obtained from the inferior myocardial wall provided incremental prognostic information for VT/VF over clinical and echocardiographic parameters (C statistic...... 0.71 versus 0.69; P=0.005). CONCLUSIONS: Assessment of regional longitudinal myocardial deformation in the inferior region provided incremental prognostic information over clinical and echocardiographic risk factors in predicting ventricular tachyarrhythmias. CLINICAL TRIAL REGISTRATION: URL: http...

Sgarbossa criteria and acute myocardial infarction.

Science.gov (United States)

Alang, Neha; Bathina, Jaya; Kranis, Mark; Angelis, Dimitrios

2010-01-01

Diagnosis of acute ST-elevation myocardial infarction in the presence of left bundle branch block is difficult. present a case of acute myocardial infarction with LBBB diagnosed and treated using the Sgarbossa criteria.

Changes of blood and myocardial tissue contents of IGF-I after development of acute myocardial infarction in rat models

International Nuclear Information System (INIS)

Cao Heng; Wei Youquan

2006-01-01

Objective: To study the changes of IGF-I contents in blood and myocardium after experimental acute myocardial infarction in rat models. Methods: Rat models of acute myocardial infarction were prepared with intraperitoneal injection of isoproterenol. Eight models were sacrificed 48h later and another 8 models were sacrificed 14 days after preparation. Serum and myocardium homogenate contents of IGF-I were measured with RIA in these models as well as 8 control rats. Results: The serum and myocardial contents of IGF-I increased in the models sacrificed at 48h, but were not significantly higher than those in the controls (P>0.05). At 14 th day, the levels were significantly higher than those in controls and at 48h (both P<0.05). The serum and myocardial contents of IGF-I were mutually correlated in the controls and 14 day models (r=0.9987, r=0.9992; P<0.01). Conclusion After myocardial infarction, the serum and myocardial IGF-I contents increased along with the course of disease in the rat models. (authors)

Canine study on myocardial ischemic memory with 18F-FDG PET/CT imaging

International Nuclear Information System (INIS)

Xie Boqia; Yang Minfu; Dou Kefei; Han Chunlei; Tian Yi; Zhang Ping; Yang Zihe; Yin Jiye; Wang Hao

2012-01-01

Objective: To explore whether the existence and duration of ischemia measured by dynamic 18 F-FDG PET/CT imaging correlated with the extent of myocardial ischemia in a canine model of myocardial ischemia-reperfusion. Methods: Canine coronary artery occlusion was carried out for 20 min (n=4) and for 40 min (n=4) followed by 24 h of open-artery reperfusion. All dogs underwent dynamic 18 F-FDG PET/CT and 99 Tc m -MIBI SPECT imaging at baseline and 1 h and 24 h after reperfusion.Quantitative analysis of myocardial 18 F-FDG uptake was performed using Carimas Core software,and the extraction ratio of 18 F-FDG (K) was calculated by the ratio of 18 F-FDG uptake rate in the ischemic area (k ischemia ) and normoperfused region (k normoperfused ). Echocardiographic data were also acquired between each PET/CT imaging study to detect the wall motion in the ischemic and normoperfused myocardium. Paired t test and non-parametric statistical tests, measured by SPSS 19.0, were used to analyze the data. Results: Coronary occlusion produced sustained, abnormal wall motion in the ischemic region for more than 1 h. Similar K values were demonstrated between the 20 min and 40 min groups at baseline (1.02 ±0.06 and 1.03 ±0.05, Z=-0.29, P>0.05). At 1 h after reperfusion, the reperfusion regions showed normal perfusion but with increased 18 F-FDG uptake, which was higher in the 40 min ischemic group than in the 20 min ischemic group (2.31 ±0.13 and 1.87 ±0.09, Z=-2.31, P<0.05). At 24 h after reperfusion, however, only the 40 min ischemic group showed slightly higher 18 F-FDG uptake than baseline (1.15 ± 0.02 and 1.03 ±0.05, t=4.32, P<0.05), whereas no significant difference was found in the 20 min ischemic group (1.05 ± 0.04 and 1.02 ± 0.06, t=0.87, P>0.05). Histological examination of the ischemic myocardium from both groups revealed neatly arranged cells without interstitial edema, hemorrhage nor inflammatory response. Conclusions: Myocardial 'ischemic memory' was

Assessment of chest pain in hypertrophic cardiomyopathy using exercise thallium-201 myocardial scintigraphy

International Nuclear Information System (INIS)

Pitcher, D.; Wainwright, R.; Maisey, M.; Curry, P.; Sowton, E.

1980-01-01

Exercise thallium-201 myocardial scintigraphy was performed in 23 patients with hypertrophic cardiomyopathy. Eighteen patients presented with chest pain which was a persistent symptom in 11. Selective coronary arteriography was performed in 16 patients and showed normal coronary arteries in 15 and insignificant luminal irregularities in one patient. Eighteen patients had abnormal scintigrams. Three had an abnormal distribution of tracer entirely attributable to asymmetric septal hypertrophy, whereas 15 had discrete tracer uptake defects which could not be explained solely by myocardial hypertrophy. In this latter group of patients three scintigraphic patterns were identified: (1) in 10 patients defects were seen in scintigrams immediately after exercise but not in delayed images obtained four to six hours later. Eight of these patients had chest pain. (2) Four patients had uptake defects seen in both initial and delayed images. One patient had chest pain. (3) In three patients, one of whom had chest pain, tracer defects were seen only in delayed images and were not apparent in the initial scintigrams. Chest pain occurred in eight out of 10 patients with scintigraphic evidence of myocardial ischaemia but was present in only three out of 13 patients with non-ischaemic scintigrams. The value of exercise thallium-201 myocardial imaging as a diagnostic technique in hypertrophic cardiomyopathy appears limited. Scintigraphic evidence of regional myocardial ischaemia in the absence of significant coronary artery disease, however, contributes to an understanding of the mechanism of angina production in patients with hypertrophic cardiomyopathy. (author)

Dual myocardial scintigraphic imaging using {sup 123}I-BMIPP and {sup 201}Tl in patients with Duchenne`s progressive muscular dystrophy

Energy Technology Data Exchange (ETDEWEB)

Sasaki, Akira [Kyorin Univ., Mitaka, Tokyo (Japan). School of Medicine

1996-03-01

Dual single photon emission computed tomography (SPECT) was performed in 30 patients with Duchenne`s muscular dystrophy (DMD) using {sup 201} thallium (Tl) for myocardial perfusion {sup 123}I-{beta}-methyl-p-iodophenylpentadecanoic acid (BMIPP) for myocardial fatty acid metabolism scintigraphy. The left ventricle was divided into 9 regions, and accumulation of the radiotracers was assessed visually for each region to calculate defect score for each tracer. There was some degree of decrease in the myocardial accumulation of both tracers in all DMD patients. Reduced accumulation was most common at the apex (BMIPP, 70%; Tl, 63%), followed by the posterior wall, lateral wall, and anterior wall. It was less common on the apical side of the ventricular septum for both tracers (BMIPP, 3%; Tl, 17%). Accumulation of Tl was lower than BMIPP in 18/30 patients (60%) and higher in 9 (30%), while both tracers showed equal accumulation in 3 (10%). BMIPP showed higher accumulation than Tl in all regions but the septum. A significant negative correlation was found between the defect scores for both tracers and the left ventricular ejection fraction (LVEF) (r=-0.629 for Tl; r=-0.567 for BMIPP). The strongest negative correlation was that between the sum of the Tl and BMIPP defect scores and the LVEF (r=-0.681). Dual SPECT myocardial scintigraphy with Tl and BMIPP provided an accurate evaluation of the progression of cardiac lesions in DMD by detecting abnormalities of the myocardial metabolism of each substance thereby enabling the assessment of left ventricular function. (author).

Protective effect of sauchinone against regional myocardial ischemia/reperfusion injury: inhibition of p38 MAPK and JNK death signaling pathways.

Science.gov (United States)

Kim, Seok Jai; Jeong, Cheol Won; Bae, Hong Beom; Kwak, Sang Hyun; Son, Jong-Keun; Seo, Chang-Seob; Lee, Hyun-Jung; Lee, JongUn; Yoo, Kyung Yeon

2012-05-01

Sauchinone has been known to have anti-inflammatory and antioxidant effects. We determined whether sauchinone is beneficial in regional myocardial ischemia/reperfusion (I/R) injury. Rats were subjected to 20 min occlusion of the left anterior descending coronary artery, followed by 2 hr reperfusion. Sauchinone (10 mg/kg) was administered intraperitoneally 30 min before the onset of ischemia. The infarct size was measured 2 hr after resuming the perfusion. The expression of cell death kinases (p38 and JNK) and reperfusion injury salvage kinases (phosphatidylinositol-3-OH kinases-Akt, extra-cellular signal-regulated kinases [ERK1/2])/glycogen synthase kinase (GSK)-3β was determined 5 min after resuming the perfusion. Sauchinone significantly reduced the infarct size (29.0% ± 5.3% in the sauchinone group vs 44.4% ± 6.1% in the control, P death signaling pathways.

Study of myocardial fatty acid metabolism of inactive sportsmen with 123-heptadecanoic acid (HDA) in the framework of complex cardiological examinations

International Nuclear Information System (INIS)

Horvath, Mihaly; Pszota, Agnes; Karman, Miklos; Szakacs, Agnes; Nemeth, Laszlo; Boeszermenyi, Ernoe; Erdelyi, Kalman; Buzassy, Gyoergy; Csendes, Eva

1986-01-01

8 inactive sportsmen and 8 heavy physical workers with similar mean age (36 years) and mean body surface (2 m 2 ) were analysed functionally and metabolically for myocardial hypertrophy. 123 I-heptadecanoic acid (HDA) scintigraphy and kinetics were carried out with methods of Feinendegen and Dudczak and using Hungarian gamma-camera. In both groups good correlation was found between the myocardial uptake of 123 I-HDA and 201 Tl. Regional alterations of myocardial perfusion during ergometric load were analyzed and compared to alterations of the ECG and echo. (author)

Abnormal myocardial capillary density in apical hypertrophic cardiomyopathy can be assessed by myocardial contrast echocardiography

International Nuclear Information System (INIS)

Moon, Jeonggeun; Cho, In-Jeong; Shim, Chi-Young; Ha, Jong-Won; Jang, Yangsoo; Chung, Namsik; Rim, Se-Joong

2010-01-01

Myocardial ischemia and dysfunction can occur in hypertrophic cardiomyopathy (HCM) because of the high muscle-to-blood ratio, even without significant coronary artery disease. Microbubbles reside only in the intravascular space and myocardial video-intensity during systole results mostly from microbubbles within capillaries. The hypothesis explored in the present study was that an abnormal capillary density in apical HCM (ApHCM) can be demonstrated using myocardial contrast echocardiography (MCE). The 56 patients were investigated (31 males, age 58±9 years; 33 ApHCM, 9 hypertensive left ventricular hypertrophy [LVH], 14 controls). MCE was performed with low-mechanical-index power modulation imaging. Tissue Doppler imaging to assess myocardial contractile function was obtained at the mitral annulus (S'), and 99m Tc-MIBI single photon emission computed tomography (SPECT) was also performed. All ApHCM patients exhibited perfusion defects at the hypertrophied segments in the systolic phase during MCE, whereas SPECT showed normal or rather increased perfusion at those sites. The cyclic variation of video-intensity was exaggerated in ApHCM when compared with the LVH or control group (% of [systolic video-intensity]/[diastolic video-intensity]: 33.0±12.3%, 88.3±19.2% and 79.4±13.9%, respectively [P<0.05]). Concurrently, MCE cyclic variation and perfusion defect size were related to decreased S' (P<0.05 for all). A perfusion defect at the hypertrophied segment, representing abnormal myocardial capillary density, was observed in ApHCM patients during MCE. The extent of MCE cyclic variation and the perfusion defect size both correlate with decreased myocardial contractile property in ApHCM. (author)

Creation and characterization of Japanese standards for myocardial perfusion SPECT. Database from the Japanese Society of Nuclear Medicine Working Group

International Nuclear Information System (INIS)

Nakajima, Kenichi; Kumita, Shinichiro; Ishida, Yoshio

2007-01-01

Standards for myocardial single-photon emission computed tomography (SPECT) adapted for a Japanese population were not available. The purpose of this study was to create standard files approved by the Japanese Society of Nuclear Medicine and to make known the characteristics of the myocardial perfusion pattern of this population. With the collaboration of nine hospitals, a total of 326 sets of exercise-rest myocardial perfusion images were accumulated from subjects with a low likelihood of cardiac diseases. The normal database included a 99m Tc-methoxyisobutylisonitrile (MIBI)/tetrofosmin myocardial perfusion study with 360 deg (n=80) and 180 deg (n=56) rotations, 201 Tl study with 360 deg (n=115) and 180 deg rotations (n=54) and a dual-isotope study with 360 deg rotation (n=27). The projection images were transferred by digital imaging and communications in medicine (DICOM) format and reconstructed and analyzed with polar maps. The projection data from multiple centers were successfully transferred to a common format for SPECT reconstruction. When the average values were analyzed using a 17-segment model, myocardial counts in the septal segment differed significantly between 180 deg and 360 deg rotation acquisitions. Regional differences were observed between men and women in the inferior and anterior regions. A tracer difference between 99m Tc and 201 Tl was also observed in some segments. The attenuation patterns differed significantly between subjects from the United States and those from Japan. Myocardial perfusion data that were specific for the Japanese population were generated. The normal database can serve a standard for nuclear cardiology work conducted in Japan. (author)

Shaping Regional Strategies of Multinational Corporations

DEFF Research Database (Denmark)

Gilbert, Dirk Ulrich; Heinicke, Patrick; Rasche, Andreas

This paper examines the factors that drive the success of multinational corporations (MNCs) in their pursuit of regional strategies. We develop a comprehensive regional success factor model to investigate the effects of regional management autonomy and regional product/service adaption...... management autonomy and regional product/service adaption are higly contingent upon contextual influences on MNCs....

Myocardial perfusion imaging with dual energy CT

Energy Technology Data Exchange (ETDEWEB)

Jin, Kwang Nam [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Radiology, SMG-SNU Boramae Medical Center, Seoul (Korea, Republic of); De Cecco, Carlo N. [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Caruso, Damiano [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Radiological Sciences, Oncology and Pathology, University of Rome “Sapienza”, Rome (Italy); Tesche, Christian [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Cardiology and Intensive Care Medicine, Heart Center Munich-Bogenhausen, Munich (Germany); Spandorfer, Adam; Varga-Szemes, Akos [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Schoepf, U. Joseph, E-mail: schoepf@musc.edu [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Division of Cardiology, Department of Medicine, Medical University of South Carolina, Charleston, SC (United States)

2016-10-15

Highlights: • Stress dual-energy sCTMPI offers the possibility to directly detect the presence of myocardial perfusion defects. • Stress dual-energy sCTMPI allows differentiating between reversible and fixed myocardial perfusion defects. • The combination of coronary CT angiography and dual-energy sCTMPI can improve the ability of CT to detect hemodynamically relevant coronary artery disease. - Abstract: Dual-energy CT (DECT) enables simultaneous use of two different tube voltages, thus different x-ray absorption characteristics are acquired in the same anatomic location with two different X-ray spectra. The various DECT techniques allow material decomposition and mapping of the iodine distribution within the myocardium. Static dual-energy myocardial perfusion imaging (sCTMPI) using pharmacological stress agents demonstrate myocardial ischemia by single snapshot images of myocardial iodine distribution. sCTMPI gives incremental values to coronary artery stenosis detected on coronary CT angiography (CCTA) by showing consequent reversible or fixed myocardial perfusion defects. The comprehensive acquisition of CCTA and sCTMPI offers extensive morphological and functional evaluation of coronary artery disease. Recent studies have revealed that dual-energy sCTMPI shows promising diagnostic accuracy for the detection of hemodynamically significant coronary artery disease compared to single-photon emission computed tomography, invasive coronary angiography, and cardiac MRI. The aim of this review is to present currently available DECT techniques for static myocardial perfusion imaging and recent clinical applications and ongoing investigations.

Quantitative Myocardial Perfusion Imaging Versus Visual Analysis in Diagnosing Myocardial Ischemia: A CE-MARC Substudy.

Science.gov (United States)

Biglands, John D; Ibraheem, Montasir; Magee, Derek R; Radjenovic, Aleksandra; Plein, Sven; Greenwood, John P

2018-05-01

This study sought to compare the diagnostic accuracy of visual and quantitative analyses of myocardial perfusion cardiovascular magnetic resonance against a reference standard of quantitative coronary angiography. Visual analysis of perfusion cardiovascular magnetic resonance studies for assessing myocardial perfusion has been shown to have high diagnostic accuracy for coronary artery disease. However, only a few small studies have assessed the diagnostic accuracy of quantitative myocardial perfusion. This retrospective study included 128 patients randomly selected from the CE-MARC (Clinical Evaluation of Magnetic Resonance Imaging in Coronary Heart Disease) study population such that the distribution of risk factors and disease status was proportionate to the full population. Visual analysis results of cardiovascular magnetic resonance perfusion images, by consensus of 2 expert readers, were taken from the original study reports. Quantitative myocardial blood flow estimates were obtained using Fermi-constrained deconvolution. The reference standard for myocardial ischemia was a quantitative coronary x-ray angiogram stenosis severity of ≥70% diameter in any coronary artery of >2 mm diameter, or ≥50% in the left main stem. Diagnostic performance was calculated using receiver-operating characteristic curve analysis. The area under the curve for visual analysis was 0.88 (95% confidence interval: 0.81 to 0.95) with a sensitivity of 81.0% (95% confidence interval: 69.1% to 92.8%) and specificity of 86.0% (95% confidence interval: 78.7% to 93.4%). For quantitative stress myocardial blood flow the area under the curve was 0.89 (95% confidence interval: 0.83 to 0.96) with a sensitivity of 87.5% (95% confidence interval: 77.3% to 97.7%) and specificity of 84.5% (95% confidence interval: 76.8% to 92.3%). There was no statistically significant difference between the diagnostic performance of quantitative and visual analyses (p = 0.72). Incorporating rest myocardial

Dorsal spinal cord stimulation obtunds the capacity of intrathoracic extracardiac neurons to transduce myocardial ischemia.

Science.gov (United States)

Ardell, Jeffrey L; Cardinal, René; Vermeulen, Michel; Armour, J Andrew

2009-08-01

Populations of intrathoracic extracardiac neurons transduce myocardial ischemia, thereby contributing to sympathetic control of regional cardiac indices during such pathology. Our objective was to determine whether electrical neuromodulation using spinal cord stimulation (SCS) modulates such local reflex control. In 10 anesthetized canines, middle cervical ganglion neurons were identified that transduce the ventricular milieu. Their capacity to transduce a global (rapid ventricular pacing) vs. regional (transient regional ischemia) ventricular stress was tested before and during SCS (50 Hz, 0.2 ms duration at 90% MT) applied to the dorsal aspect of the T1 to T4 spinal cord. Rapid ventricular pacing and transient myocardial ischemia both activated cardiac-related middle cervical ganglion neurons. SCS obtunded their capacity to reflexly respond to the regional ventricular ischemia, but not rapid ventricular pacing. In conclusion, spinal cord inputs to the intrathoracic extracardiac nervous system obtund the latter's capacity to transduce regional ventricular ischemia, but not global cardiac stress. Given the substantial body of literature indicating the adverse consequences of excessive adrenergic neuronal excitation on cardiac function, these data delineate the intrathoracic extracardiac nervous system as a potential target for neuromodulation therapy in minimizing such effects.

Evaluation of myocardial damage in Duchenne's muscular dystrophy with thallium-201 myocardial SPECT

Energy Technology Data Exchange (ETDEWEB)

Tamura, Takuhisa; Shibuya, Noritoshi (Kawatana National Hospital, Nagasaki (Japan)); Hashiba, Kunitake; Oku, Yasuhiko; Mori, Hideki; Yano, Katsusuke

1993-01-01

Myocardial damage and cardiopulmonary functions in patients with Duchenne's muscular dystrophy (DMD) were assessed using thallium-201 myocardial single-photon emission computed tomography (SPECT) and technetium-99m multigated radionuclide angiography. Twenty-five patients with DMD were divided into 4 groups according to percent of perfusion defect (%PD) calculated by the bull's-eye method and age. PD was detected in 24 (96.0%) of 25 patients with DMD, and it spread from the left ventricular lateral wall to the anterior wall and/or interventricular septum. PD was detected even in a 6-year-old DMD boy. Patients in Group I (%PD[>=]10% and age<15 years old) were shown to have a higher risk of left-sided heart failure without respiratory failure. Patients in Group II (%PD[>=]10 and age[>=]15) showed decreased pulmonary function and worsened arterial blood gas values as compared with Group IV (%PD<10 and age[>=]15). There was no significant difference in cardiac function among the 4 groups. It is postulated that myocardial damage in Group II patients is dependent primarily on a deficiency of dystrophin and on chronic respiratory failure, and that some of them are at risk of cardiopulmonary failure. It is concluded that myocardial SPECT is useful for the early diagnosis of myocardial damage and evaluation of cardiopulmonary function in DMD patients. (author).

Myocardial infarction, androgen and the skin.

Science.gov (United States)

Halim, M M; Meyrick, G; Jeans, W D; Murphy, D; Burton, J L

1978-01-01

Various indices of masculinity were compared in 48 men who had recovered from myocardial infarction and in their age-matched controls. We found little evidence to support the idea that myocardial infarction is related to increased androgenic stimulation. The patients with myocardial infarction had no increase in plasma testosterone, muscle thickness, sebum excretion rate, maximal sweat secretion rate, male pattern alopecia or density of terminal body hair, but as a group they had a slight increase in skin and bone thickness compared with the controls.

Non-photic solar associations of heart rate variability and myocardial infarction

Science.gov (United States)

Cornélissen, Germaine; Halberg, Franz; Breus, Tamara; Syutkina, Elena V.; Baevsky, Roman; Weydahl, Andi; Watanabe, Yoshihiko; Otsuka, Kuniaki; Siegelova, Jarmila; Fiser, Bohumil; Bakken, Earl E.

2002-03-01

Alignment of serial epidemiological, physiological, including electrocardiographic data with variations in galactic cosmic rays, geomagnetic activity, and atmospheric pressure suggests the possibility of links among these physical environmental variations and health risks, such as myocardial infarctions and ischemic strokes, among others. An increase in the incidence of myocardial infarction in association with magnetic storms, reported by several investigators from Russia, Israel, Italy and Mexico, accounts in Minnesota for a 5% (220cases/year) increase in mortality during years of maximal solar activity by comparison with years of minimal solar activity. Magnetic storms are also found to decrease heart rate variability (HRV), indicating a possible mechanism since a reduced HRV is a prognostic factor for coronary artery disease and myocardial infarction. Longitudinal electrocardiographic monitoring for a week or much longer spans in different geographic locations, notably in the auroral oval, further suggests that the decrease in HRV affects spectral regions other than that around 3.6s (0.15-0.40Hz), reportedly associated with the parasympathetic nervous system. Differences in some associations are observed from solar cycle to solar cycle, and as a function of solar cycle stage, a finding resolving controversies. Coordinated physiological and physical monitoring, the scope of an international project on the Biosphere and the Cosmos, seeks reference values for a better understanding of environmental effects on human health and for testing the merit of space weather reports that could prompt countermeasures in space and on earth. Physiological data being collected systematically worldwide and morbidity/mortality statistics from causes such as myocardial infarction and stroke constitute invaluable data bases for assessing changes within the physiological range, for detecting environmental effects and for recognizing endogenous as well as exogenous disease

Myocardial thallium-201 kinetics in normal and ischemic myocardium

International Nuclear Information System (INIS)

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

1981-01-01

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

Emission computed tomography with technetium-99m pyrophosphate for delineating location and size of acute myocardial infarction in man

Energy Technology Data Exchange (ETDEWEB)

Tamaki, S; Kadota, K; Kambara, H; Suzuki, Y; Nohara, R; Murakami, T; Kawai, C; Tamaki, N; Torizuka, K [Kyoto Univ. (Japan). Faculty of Medicine

1984-07-01

Emission computed tomography with technetium-99m pyrophosphate was used to delineate the location and estimate the size of myocardial infarcts in 20 patients with documented acute myocardial infarction. Tomography was performed after planar imaging within 2-5 days after the onset of infarction. Infarct volume was measured from the tomographic images by computerised planimetry and compared with the cumulative release of creatine kinase MB isoenzyme. The planar images showed discrete myocardial uptake in 13 of the 20 patients and diffuse uptake throughout the cardiac region in the remaining seven. In contrast, the tomographic images clearly delineated myocardial uptake by avoiding confusion of myocardial activity with that of surrounding structures, particularly bones, in all patients. For the 10 patients whose infarct size was assessed by analysis of the creatine kinase MB curve there was a close correlation between infarct volume estimated by tomography and by cumulative creatine kinase MB release. Thus emission computed tomography can provide a three dimensional map of technetium-99m pyrophosphate distribution within the heart and is thus able accurately to localise and estimate the size of myocardial infarcts in man.

Emission computed tomography with technetium-99m pyrophosphate for delineating location and size of acute myocardial infarction in man

International Nuclear Information System (INIS)

Tamaki, S.; Kadota, K.; Kambara, H.; Suzuki, Y.; Nohara, R.; Murakami, T.; Kawai, C.; Tamaki, N.; Torizuka, K.

1984-01-01

Emission computed tomography with technetium-99m pyrophosphate was used to delineate the location and estimate the size of myocardial infarcts in 20 patients with documented acute myocardial infarction. Tomography was performed after planar imaging within 2-5 days after the onset of infarction. Infarct volume was measured from the tomographic images by computerised planimetry and compared with the cumulative release of creatine kinase MB isoenzyme. The planar images showed discrete myocardial uptake in 13 of the 20 patients and diffuse uptake throughout the cardiac region in the remaining seven. In contrast, the tomographic images clearly delineated myocardial uptake by avoiding confusion of myocardial activity with that of surrounding structures, particularly bones, in all patients. For the 10 patients whose infarct size was assessed by analysis of the creatine kinase MB curve there was a close correlation between infarct volume estimated by tomography and by cumulative creatine kinase MB release. Thus emission computed tomography can provide a three dimensional map of technetium-99m pyrophosphate distribution within the heart and is thus able accurately to localise and estimate the size of myocardial infarcts in man. (author)

Melatonin protects against myocardial hypertrophy induced by lipopolysaccharide.

Science.gov (United States)

Lu, Qi; Yi, Xin; Cheng, Xiang; Sun, Xiaohui; Yang, Xiangjun

2015-04-01

Melatonin is thought to have the ability of antiatherogenic, antioxidant, and vasodilatory. It is not only a promising protective in acute myocardial infarction but is also a useful tool in the treatment of pathological remodeling. However, its role in myocardial hypertrophy remains unclear. In this study, we investigated the protective effects of melatonin on myocardial hypertrophy induced by lipopolysaccharide (LPS) and to identify their precise mechanisms. The cultured myocardial cell was divided into six groups: control group, LPS group, LPS + ethanol (4%), LPS + melatonin (1.5 mg/ml) group, LPS + melatonin (3 mg/ml) group, and LPS + melatonin (6 mg/ml) group. The morphologic change of myocardial cell was observed by inverted phase contrast microscope. The protein level of myocardial cell was measured by Coomassie brilliant blue protein kit. The secretion level of tumor necrosis factor-α (TNF-α) was evaluated by enzyme-linked immunosorbent assay (ELISA). Ca(2+) transient in Fura-2/AM-loaded cells was measured by Till image system. The expression of Ca(2+)/calmodulin-dependent kinase II (CaMKII) and calcineurin (CaN) was measured by Western blot analysis. Our data demonstrated that LPS induced myocardial hypertrophy, promoted the secretion levels of TNF-α, and increased Ca(2+) transient level and the expression of CaMKII and CaN. Administration of melatonin 30 min prior to LPS stimulation dose-dependently attenuated myocardial hypertrophy. In conclusion, the results revealed that melatonin had the potential to protect against myocardial hypertrophy induced by LPS in vitro through downregulation of the TNF-α expression and retains the intracellular Ca(2+) homeostasis.

The importance of sex-specific quantitative criteria in thallium-201 myocardial scintigraphy

International Nuclear Information System (INIS)

Rabinovitch, M.A.; Suissa, S.; Elstein, J.; Turek, M.; Addas, A.; Burgess, J.H.; Rosenthall, L.

1984-01-01

Breast attenuation is an important cause of artifactual cold spots on visually interpreted TL-201 myocardial images. This study was undertaken to determine the need for sex-specific criteria in the quantitative analysis of exercise-redistribution TL-201 myocardial scintigraphy (SCINT). The studies of 13 normal females (F) and 12 normal males (M) were processed according to the method of a previous study. Significant sexual differences were found in 7/12 regional uptake (U) proportions, 9/11 regional washout (WO) percentages, 0/3 image redistribution indices, and 0/1 lung to heart ratio. The differences primarily reflected a proportionately decreased anterior and septal uptake in F, a proportionately decreased inferior and inferoapical U in M, and faster WO in F. Sex-specific and total population normal boundaries were set a +- 3SD of the mean for each parameter. Sex-specific boundaries were narrower, and, for 5 parameters (4U and 1WO), contained within the total population boundaries. It was estimated that these differences in boundaries would result in a 6 to 25% discrepancy in patient classification. These results predict that a subset of M and F with coronary artery stenoses could be misclassified as normal by total population criteria, while properly classified as abnormal by sex-specific criteria. The authors conclude that since important differences exist between M and F in the detected pattern of TL-201 myocardial U and WO, sex-specific cr4iteria may enhance the predictive accuracy of SCINT

Assessment of left ventricular function by 201Tl FCG-gated myocardial SPECT

International Nuclear Information System (INIS)

Toba, Masahiro; Ishida, Yoshio; Fukuchi, Kazuki; Fukushima, Kazuhito; Katafuchi, Tetsurou; Hayashida, Kohei; Oka, Hisashi; Takamiya, Makoto

1999-01-01

We applied the QGS program for LV function analysis (described by Germano, 1995) to a 201 Tl SPECT study at rest, and estimated its accuracy. We performed 201 Tl ECG-gated myocardial SPECT in 25 patients with ischemic heart disease under an acquisition time used in the routine 99m Tc ECG-gated SPECT study. The quality of the gated images was visually assessed with a 4-point grading system. LVEDV, LVESV, LVEF determined by the QGS program were compared with those by Simpson's method on biplane LVG in 25 patients. Regional wall motion scores in 7 myocardial segments were assessed on the three-dimensional display created by the QGS program and the cine display of biplane LVG with a 5-point grading system. Wall motion scores obtained by the QGS program were compared with those by LVG. Although 72.0% of 201 Tl ECG-gated SPECT images were fair or poor in image quality, there were good correlations between the values obtained by the QGS program and LVG (LVEDV: r=0.82, LVESV: r=0.88, LVEF: r=0.89). In addition, wall motion scores by the QGS program were correspondent to those by LVG in 77.1% of all 175 myocardial segments. We conclude that the QGS program provides high accuracy in evaluating left ventricular function even from 201 Tl ECG-gated myocardial SPECT data. (author)

Myocardial infarction in Swedish subway drivers.

Science.gov (United States)

Bigert, Carolina; Klerdal, Kristina; Hammar, Niklas; Gustavsson, Per

2007-08-01

Particulate matter in urban air is associated with the risk of myocardial infarction in the general population. Very high levels of airborne particles have been detected in the subway system of Stockholm, as well as in several other large cities. This situation has caused concern for negative health effects among subway staff. The aim of this study was to investigate whether there is an increased incidence of myocardial infarction among subway drivers. Data from a population-based case-control study of men aged 40-69 in Stockholm County in 1976-1996 were used. The study included all first events of myocardial infarction in registers of hospital discharges and deaths. The controls were selected randomly from the general population. National censuses were used for information on occupation. Altogether, 22 311 cases and 131 496 controls were included. Among these, 54 cases and 250 controls had worked as subway drivers. The relative risk of myocardial infarction among subway drivers was not increased. It was 0.92 [95% confidence interval (95% CI) 0.68-1.25] when the subway drivers were compared with other manual workers and 1.06 (95% CI 0.78-1.43) when the subway drivers were compared with all other gainfully employed men. Subgroup analyses indicated no influence on the risk of myocardial infarction from the duration of employment, latency time, or time since employment stopped. Subway drivers in Stockholm do not have a higher incidence of myocardial infarction than other employed persons.

Value of the Doppler index of myocardial performance in the early phase of acute myocardial infarction

DEFF Research Database (Denmark)

Poulsen, S H; Jensen, S E; Tei, C

2000-01-01

Prospective assessment of a nongeometric Doppler-derived index of combined systolic and diastolic myocardial performance was performed in 64 patients with acute myocardial infarction (MI) within 1 hour after their arrival to the hospital and in 39 age-matched healthy subjects. The index is defined...

High fat diet-induced glucose intolerance impairs myocardial function, but not myocardial perfusion during hyperaemia: a pilot study

Directory of Open Access Journals (Sweden)

van den Brom Charissa E

2012-06-01

Full Text Available Abstract Background Glucose intolerance is a major health problem and is associated with increased risk of progression to type 2 diabetes mellitus and cardiovascular disease. However, whether glucose intolerance is related to impaired myocardial perfusion is not known. The purpose of the present study was to study the effect of diet-induced glucose intolerance on myocardial function and perfusion during baseline and pharmacological induced hyperaemia. Methods Male Wistar rats were randomly exposed to a high fat diet (HFD or control diet (CD (n = 8 per group. After 4 weeks, rats underwent an oral glucose tolerance test. Subsequently, rats underwent (contrast echocardiography to determine myocardial function and perfusion during baseline and dipyridamole-induced hyperaemia (20 mg/kg for 10 min. Results Four weeks of HFD feeding resulted in glucose intolerance compared to CD-feeding. Contractile function as represented by fractional shortening was not altered in HFD-fed rats compared to CD-fed rats under baseline conditions. However, dipyridamole increased fractional shortening in CD-fed rats, but not in HFD-fed rats. Basal myocardial perfusion, as measured by estimate of perfusion, was similar in CD- and HFD-fed rats, whereas dipyridamole increased estimate of perfusion in CD-fed rats, but not in HFD-fed rats. However, flow reserve was not different between CD- and HFD-fed rats. Conclusions Diet-induced glucose intolerance is associated with impaired myocardial function during conditions of hyperaemia, but myocardial perfusion is maintained. These findings may result in new insights into the effect of glucose intolerance on myocardial function and perfusion during hyperaemia.

Sodium bicarbonate-augmented stress thallium myocardial scintigraphy

Energy Technology Data Exchange (ETDEWEB)

Sarin, Badal; Chugh, Pradeep Kumar; Kaushal, Dinesh; Soni, Nakse Lal; Sawroop, Kishan; Mondal, Anupam; Bhatnagar, Aseem [Department of Nuclear Medicine, Institute of Nuclear Medicine and Allied Sciences, Brig. S. K. Mazumdar Road, 110054, Delhi (India)

2004-04-01

It is well known that sodium bicarbonate in pharmacological doses induces transient alkalosis, causing intracellular transport of serum potassium. The aims of this study were (a) to investigate whether, in humans, myocardial thallium-201 uptake can be augmented by pretreatment with a single bolus of sodium bicarbonate at a pharmacological dose, (b) to verify general safety aspects of the intervention and (c) to evaluate the clinical implications of augmentation of {sup 201}Tl uptake, if any. Routine exercise myocardial scintigraphy was performed twice in eight adult volunteers (five normal and three abnormal), once without intervention and the second time (within a week) following intravenous administration of sodium bicarbonate (88 mEq in 50 ml) as a slow bolus 1 h prior to the injection of {sup 201}Tl. Conventional myocardial thallium study was compared with sodium bicarbonate interventional myocardial scintigraphy with respect to myocardial uptake (counts per minute per mCi injected dose), washout patterns in normal and abnormal myocardial segments, and overall clinical interpretation based on planar and single-photon emission tomographic (SPET) images. All patients remained asymptomatic after the intervention. A mean increase of 53% in myocardial uptake of thallium was noted in post-exercise acquisitions after the intervention, confirming uptake of the tracer via the potassium-hydrogen pump and its augmentation by transient alkalosis. The washout pattern remained unchanged. The visual quality of planar and SPET images improved significantly after the intervention. Out of the five abnormal myocardial segments identified in three cases, four showed significant filling-in after the intervention, causing the diagnosis to be upgraded from ''partial scar'' to ''ischaemia'', or from ''ischaemia'' to ''normal''. The overall scan impression changed in two out of three such cases. Sodium

The development of iodine-123-labeled-methyl-branched fatty acids for myocardial SPECT imaging

International Nuclear Information System (INIS)

Knapp, F.F. Jr.; Kropp, J.

1994-01-01

Iodine-123-labeled fatty acids represent unique metabolic probes for correlation of energy substrate metabolism with regional myocardial viability. Interest in the use of these agents results from differences which are often observed in various types of heart disease between regional myocardial fatty acid uptake patterns and flow tracer distribution. Although the physiological basis is not completely understood, differences between regional fatty acid and flow tracer distribution may reflect alterations in important parameters of metabolism which can be useful for patient management or therapeutic strategy decision making. The iodine-123-labeled 15-(p-iodophenyl)-3-R,S-methylpentadecanoic acid (BMIPP) fatty acid analogue was developed at the Oak Ridge National Laboratory and was recently introduced as ''Cardiodine trademark'' in 1993 by Nihon Medi-Physics for commercial distribution in Japan. Iodine-123-BMPP is also being used in clinical studies on an institutional approval basis at several institutions in Europe and the US. This paper describes the development of the concept of fatty acid ''metabolic trapping'' of methyl-branched fatty acids and their use for single photon emission computerized tomographic cardiac imaging

The region makes the difference: disparities in management of acute myocardial infarction within Switzerland.

Science.gov (United States)

Insam, Charlène; Paccaud, Fred; Marques-Vidal, Pedro

2014-05-01

In Switzerland, health policies are decided at the local level, but little is known regarding their impact on the management of acute myocardial infarction (AMI). In this study, we assessed geographical differences within Switzerland regarding management of AMI. Cross-sectional study. Swiss hospital discharge database for period 2007-2008 (26,204 discharges from AMI). Seven Swiss regions (Leman, Mittelland, Northwest, Zurich, Central, Eastern, and Ticino) were analysed. Almost 53.7% of discharges from AMI were managed in a single hospital, ranging from 62.1% (Leman) to 31.6% (Ticino). The highest intensive care unit admission rate was in Leman (69.4%), the lowest (16.9%) in Ticino (Swiss average: 36.0%). Intracoronary revascularization rates were highest in Leman (51.1%) and lowest (30.9%) in Central Switzerland (average: 41.0%). Bare (non-drug-eluting) stent use was highest in Leman (61.4%) and lowest (16.9%) in Ticino (average: 42.1%), while drug-eluting stent use was highest (83.2%) in Ticino and lowest (38.6%) in Leman (average: 57.9%). Coronary artery bypass graft rates were highest (4.8%) in Ticino and lowest (0.5%) in Eastern Switzerland (average: 2.8%). Mechanical circulatory assistance rates were highest (4.2%) in Zurich and lowest (0.5%) in Ticino (average: 1.8%). The differences remained after adjusting for age, single or multiple hospital management, and gender. In Switzerland, significant geographical differences in management and revascularization procedures for AMI were found.

Time course evaluation of myocardial perfusion after reperfusion therapy by 99mTc-tetrofosmin SPECT in patients with acute myocardial infarction.

Science.gov (United States)

Tanaka, R; Nakamura, T

2001-09-01

Myocardial perfusion imaging with 99mTc-labeled agents immediately after reperfusion therapy can underestimate myocardial salvage. It is also conceivable that delayed imaging is useful for assessing the risk area. However, to our knowledge, very few studies have sequentially evaluated these image changes. We conducted 99mTc-tetrofosmin (TF) and 123I-beta-methyl-p-iodophenylpentadecanoic acid (BMIPP) SPECT before and after reperfusion to treat acute myocardial infarction and quantified changes in TF myocardial accumulation and reverse redistribution. Seventeen patients with a first myocardial infarction underwent successful reperfusion. We examined SPECT images obtained at the onset (preimage), those acquired 30 min (early image) and 6 h (delayed image) after TF injection, and images acquired 1, 4, 7, and 20 d after reperfusion (post-1-d, post-4-d, post-7-d, and post-20-d image, respectively). We also examined BMIPP SPECT images after 7 +/- 1.8 d (BMIPP image). Polar maps were divided into 48 segments to calculate percentage uptake, and time course changes in segment numbers below 60% were observed as abnormal area. Moreover, cardiac function was analyzed by gated TF SPECT on 1 and 20 d after reperfusion. In reference to the abnormal area on the early images, the post-1-d image was significantly improved compared with the preimage (P < 0.01) as was the post-7-d image compared with the post-1-d and post-4-d images (P < 0.05, respectively). However, post-20-d and post-7-d images did not significantly differ. Therefore, the improvement in myocardial accumulation reached a plateau 7 d after reperfusion. On the other hand, the abnormal area on the delayed images was significantly greater (P < 0.01) compared with that on the early images from 4 to 20 d after reperfusion, as the value was essentially constant. The correlations of the abnormal area between the preimage and the post-7-d delayed image, the preimage and the BMIPP image, and the post-7-d delayed image and the

Evaluation of myocardial involvement in Duchenne progressive muscular dystrophy with thallium-201 myocardial perfusion imaging

International Nuclear Information System (INIS)

Kawai, Naoki; Yamamoto, Shuhei; Okada, Mitsuhiro

1983-01-01

Myocardial involvement in progressive muscular dystrophy of the Duchenne type was evaluated in 19 patients using thallium-201 myocardial perfusion imaging. The qualitative analysis was performed in anterior, 3 left anterior oblique and left lateral projection images by three experienced physicians. Distinct perfusion defects were shown in 13 patients, especially in LV posterolateral or posterior walls (11 patients). There was no significant relationship between the presence of perfusion defects and the skeletal muscle changes or thoracic deformities assessed by transmission computed tomography. Slightly increased thallium-201 activity in RV free wall and lungs was shown in nine and one patient, respectively. The extensive perfusion defects were shown in 2 patients who died of congestive heart failure 1 to 2 years after the scintigraphic study. The myocardial scintigraphic changes were considered to be minimal in 7 of 9 patients who underwent two serial scintigraphic studies in 2 to 3 years. It was concluded that the thallium myocardial perfusion imaging was a useful clinical technique to evaluate the cardiomyopathy in Duchenne progressive muscular dystrophy. (author)

Evaluation of myocardial involvement in Duchenne progressive muscular dystrophy with thallium-201 myocardial perfusion imaging

Energy Technology Data Exchange (ETDEWEB)

Kawai, Naoki; Yamamoto, Shuhei; Okada, Mitsuhiro (Nagoya Univ. (Japan). Faculty of Medicine)

1983-12-01

Myocardial involvement in progressive muscular dystrophy of the Duchenne type was evaluated in 19 patients using thallium-201 myocardial perfusion imaging. The qualitative analysis was performed in anterior, 3 left anterior oblique and left lateral projection images by three experienced physicians. Distinct perfusion defects were shown in 13 patients, especially in LV posterolateral or posterior walls (11 patients). There was no significant relationship between the presence of perfusion defects and the skeletal muscle changes or thoracic deformities assessed by transmission computed tomography. Slightly increased thallium-201 activity in RV free wall and lungs was shown in nine and one patient, respectively. The extensive perfusion defects were shown in 2 patients who died of congestive heart failure 1 to 2 years after the scintigraphic study. The myocardial scintigraphic changes were considered to be minimal in 7 of 9 patients who underwent two serial scintigraphic studies in 2 to 3 years. It was concluded that the thallium myocardial perfusion imaging was a useful clinical technique to evaluate the cardiomyopathy in Duchenne progressive muscular dystrophy.

Evaluation of regional wall motion in myocardial infarction using animation ECG gated cardiac computed tomography

International Nuclear Information System (INIS)

Shimizu, Takahiko; Hyodo, Haruo; Hayashi, Terumi; Yamamoto, Hideo; Yagi, Shigeru

1984-01-01

Regional wall motion of the left ventricle was evaluated in 21 patients with myocardial infarction using an animation system of gated cardiac computed tomographic (CT) images (animation gated CCT). The results obtained were compared with data by two-dimensional echocardiography (2-DE). 1. Evaluation of the asynergic area by animation gated CCT and 2-DE: Animation gated CCT detected the following specific regions with asynergy established by 2-DE; 10/10 cases (100%) at the anterior wall of the left ventricle, 14/14 cases (100%) at the interventricular septum, and 9/11 cases (81.8%) at the infero-posterior wall. In addition, one false positive case and one negative case were observed at the lateral wall and the apex, respectively. Of 37 instances with asynergic areas established by 2-DE, 21 cases or 89.2% were detected by animation gated CCT; the sensitivity was 91.9%. 2. Evaluation of severity of asynergy by animation gated CCT and 2-DE: The degree of asynergy evaluated by both methods was compared with each other, and the agreement was as follows: 10/10 cases (100%) at the left-ventricular anterior wall, 13/13 cases (100%) at the interventricular septum, and 7/9 cases (77.8%) at the infero-posterior wall. 3. Evaluation of the asynergic area by nonanimation gated CCT and 2-DE: Nonanimation gated CCT detected asynergic areas ascertained by 2-DE at the following areas; 8/10 cases (80%) at the left-ventricular anterior wall, 12/14 cases (85.7%) at the interventricular septum, and 4/11 cases (36.4%) at the infero-posterior wall. The difference between animation and nonanimation gated CCT was statistically significant (p<0.05). The severity of asynergy could not be evaluated by nonanimation gated CCT. (J.P.N.)

Effect of streptozotocin-induced diabetes on myocardial blood flow reserve assessed by myocardial contrast echocardiography in rats

Directory of Open Access Journals (Sweden)

Weytjens Caroline

2008-09-01

Full Text Available Abstract The role of structural and functional abnormalities of small vessels in diabetes cardiomyopathy remains unclear. Myocardial contrast echocardiography allows the quantification of myocardial blood flow at rest and during dipyridamole infusion. The aim of the study was to determine the myocardial blood flow reserve in normal rats compared with Streptozotocin-induced diabetic rats using contrast echocardiography. Methods We prospectively studied 40 Wistar rats. Diabetes was induced by intravenous streptozotocin in 20 rats. All rats underwent baseline and stress (dipyridamole: 20 mg/kg high power intermittent imaging in short axis view under anaesthesia baseline and after six months. Myocardial blood flow was determined and compared at rest and after dipyridamole in both populations. The myocardial blood flow reserve was calculated and compared in the 2 groups. Parameters of left ventricular function were determined from the M-mode tracings and histological examination was performed in all rats at the end of the study. Results At six months, myocardial blood flow reserve was significantly lower in diabetic rats compared to controls (3.09 ± 0.98 vs. 1.28 ± 0.67 ml min-1 g-1; p Conclusion In this animal study, diabetes induced a functional alteration of the coronary microcirculation, as demonstrated by contrast echocardiography, a decrease in capillary density and of the cardiac systolic function. These findings may offer new insights into the underlying mechanisms of diabetes cardiomyopathy.

Evaluation of myocardial damage and cardiac residual capacity by Tl-201 myocardial scintigraphy in valvular heart diseases

International Nuclear Information System (INIS)

Indo, Shunju

1992-01-01

This study was performed to clarify whether the extent-score (Ex-Score) calculated by Tl-201 myocardial scintigraphy is a reliable indicator of the severity of myocardial damage and cardiac residual capacity in valvular heart diseases. The subjects consisted of 38 patients (10 with aortic regurgitation (AR), 4 with aortic stenosis (AS), 13 with mitral regurgitation (MR) and 11 with mitral stenosis (MS)). Ex-Scores were significantly correlated with the severity of myocardial damage found in biopsied specimens obtained intraoperatively (correlation efficiency to Ex-Score with cell diameter in AR, % fibrosis in AR, cell diameter in AS, electron microscopic score in MR and % fibrosis in MS was 0.873, 0.734, 0.970, 0.913 and 0.659, respectively). Ex-Scores were also correlated with cardiac residual capacity determined by radioisotope angiography (correlation efficiency to Ex-Score with %Δ ejection fraction in AR, %Δ end-systolic volume in MR, %Δ end-diastolic volume in MS was -0.764, 0.790 and -0.763, respectively). These results suggest that the severity of myocardial damage and cardiac residual capacity can be estimated by Tl-201 myocardial scintigraphy (Ex-Score) in valvular heart diseases. (author)

MYOCARDIAL DEFORMATION AND COMPLETE LEFT BUNDLE BRANCH BLOCK

Directory of Open Access Journals (Sweden)

E. N. Pavlyukova

2015-12-01

Full Text Available Tissue Doppler imaging is evolving as a useful echocardiographic tool for quantitative assessment of left ventricular systolic and diastolic function. Over the last 10 years, myocardial deformation imaging has become possible initially with tissue Doppler , and more recently with myocardial speckle-tracking using 2D echocardiography. Unlike simple tissue velocity measurements, deformation measurements are specific for the region of interest. Strain rate or strain measurements have been used as sensitive indicators for subclinical diseases, and it is the most widely used tool to assess mechanical dyssynchrony. Left bundle branch block is a frequent, etiologically heterogeneous, clinically hostile and diagnostically challenging entity. About 2% of patients underwent cardiac stress testing show stable or intermittent left bundle branch block. Presence of left bundle branch block is associated with a lower and slower diastolic coronary flow velocity especially during hyperemia. Stress echocardiography is the best option for the diagnosis of ischemic heart disease, albeit specificity and sensitivity reduce in patients with left bundle branch block in the territory of left anterior descending artery in presence of initial septum dyskinesia.

Clinical significance of myocardial 123I-BMIPP imaging in patients with myocardial infarction

International Nuclear Information System (INIS)

Narita, Michihiro; Kurihara, Tadashi; Shindoh, Takashi; Honda, Minoru

1997-01-01

We studied 55 patients with myocardial infarction (MI), 14 patients with recent MI (RMI) and 41 patients with old MI (OMI), and myocardial images were divided into 17 segments and myocardial uptake of the radionuclide was graded from 0 (normal) to 3 (maximal abnormality). In 28 patients we compared segmental defect score (SDS) with wall motion index (WMI) which were obtained by centerline method at the corresponded segments. As a whole, the mean total defect scores (TDSs) of BMIPP and exercise stress (Ex) were similar and they were greater than the mean TDS of resting perfusion. In 30 patient TDS of BMIPP was greater than that of TDS of resting perfusion. In 24 patients perfusion abnormality developed by Ex and the location of BMIPP abnormality coincided with the abnormality of Ex. But in the other 6 patients Ex did not induce any abnormality and they were all RMI and infarcted coronary artery was patent. However in the group with TDS of BMIPP identical to TDS of resting perfusion (25 patients), 92% did not show myocardial perfusion abnormality after Ex. In the comparison of SDS and WMI, myocardial segments were divided into 3 groups; both SDSs of BMIPP and resting perfusion were normal or borderline abnormality (Group 1, 82 segments), SDS of resting perfusion was normal or borderline and SDS of BMIPP was definitely abnormal (Group 2, 10 segments) and both SDSs of BMIPP and resting perfusion were definitely abnormal (Group 3, 48 segments). In Group 1, WMS was significantly greater than those of Group 2 and Group 3. But there was no difference between Group 2 and 3. These findings suggested that in the segments with mismatch between BMIPP and resting perfusion reflects stunned myocardium. (K.H.)

Detection of myocardial ischemia of hypertrophic cardiomyopathy with gated 99Tcm-MIBI myocardial perfusion imaging

International Nuclear Information System (INIS)

Jia Peng; Guo Wanhua; Du Minghua; Gao Ling

2010-01-01

Objective: To evaluate the value of gated 99 Tc m -methoxyisobutylisonitrile (MIBI) myocardial perfusion imaging in detection of myocardial ischemia in hypertrophic cardiomyopathy. Methods: Sixty-nine patients with clinically proven hypertrophic cardiomyopathy were divided into 2 groups using coronary angiogram as 'gold standard': positive group (n=19, narrowing ≥ 50%) and negative group (n=50, narrowing 99 Tc m -MIBI myocardial perfusion imaging was performed and positive in all 69 patients (41 males, 28 females, aged 35-75 years). Comparative analysis between the two groups was carried out using t-test. Results: In the positive group, reversible and irreversible perfusion defects were detected in 9 and 10 patients, respectively. Left ventricular ejection fraction (LVEF) increased to (69.1 ± 2.8)% in 8 patients and decreased to (42.8 ± 2.1)% in 11 patients. In the negative group, reversible and irreversible perfusion defects were found in 37 and 13 patients, respectively. LVEF increased to (70.8 ± 4.0)% in 38 patients and decreased to (48.9 ± 2.7)% in 12 patients. The values of ischemic area, severity and extent of perfusion defect, and LVEF were significantly different between the two groups (t=9.28, 16.51, 2.65; P 99 Tc m -MIBI myocardial perfusion imaging is valuable in assessing patients with hypertrophic cardiomyopathy. Detection for the presence or absence of coexisting coronary artery disease and myocardial ischemia has an important prognostic indication and management indication for these patients. (authors)

Use of resting myocardial scintigraphy during chest pain to exclude diagnosis of acute myocardial infarction

International Nuclear Information System (INIS)

Barbirato, Gustavo Borges; Azevedo, Jader Cunha de; Felix, Renata Christian Martins; Correa, Patricia Lavatori; Volschan, Andre; Viegas, Monica; Pimenta, Lucia; Dohmann, Hans Fernando Rocha; Mesquita, Evandro Tinoco; Mesquita, Claudio Tinoco

2009-01-01

Background: Images of myocardial perfusion taken during an episode of chest pain have been used for patients in the emergency department. Objective: To evaluate the operating characteristics of 99m Tc-Tetrofosmin scintigraphy during an episode of chest pain to exclude the diagnosis of cute myocardial infarction. Methods: One hundred and eight patients admitted with chest pain, or up to four hours after the end of symptoms and non diagnostic electrocardiogram, underwent resting scintigraphy and measurement of troponin I concentrations. Patients with a history of myocardial infarction (MI) were not excluded (24 patients). Troponin I concentrations were determined at admission and 6 hours later. Nuclear physicians performed a blind analysis of the images, and myocardial infarction was confirmed whenever troponin I level increase was three times that of the control. Results: Resting perfusion image was abnormal in all 6 patients with MI. Only 1 patient had a normal image and increased troponin levels. Fifty-five patients had positive images without MI, and 46 patients had normal images and troponin levels. The prevalence of the disease was 6.5%. The sensitivity and specificity of the resting images during an episode of chest pain to diagnose MI was 85.7% and 45.5%, respectively. The negative predictive value was 97.7%. Conclusion: Patients undergoing chest pain protocol with SPECT showed an excellent negative predictive value to exclude diagnosis of myocardial infarction. These results suggest that resting perfusion image is an important tool at the chest pain unit. (author)

Integration Research for Shaping Sustainable Regional Landscapes

Directory of Open Access Journals (Sweden)

David J. Brunckhorst

2005-01-01

Full Text Available Ecological and social systems are complex and entwined. Complex social-ecological systems interact in a multitude of ways at many spatial scales across time. Their interactions can contribute both positive and negative consequences in terms of sustainability and the context in which they exist affecting future landscape change. Non-metropolitan landscapes are the major theatre of interactions where large-scale alteration occurs precipitated by local to global forces of economic, social, and environmental change. Such regional landscape effects are critical also to local natural resource and social sustainability. The institutions contributing pressures and responses consequently shape future landscapes and in turn influence how social systems, resource users, governments, and policy makers perceive those landscapes and their future. Science and policy for “sustainable” futures need to be integrated at the applied “on-ground” level where products and effects of system interactions are fully included, even if unobserved. Government agencies and funding bodies often consider such research as “high-risk.” This paper provides some examples of interdisciplinary research that has provided a level of holistic integration through close engagement with landholders and communities or through deliberately implementing integrative and innovative on-ground experimental models. In retrospect, such projects have to some degree integrated through spatial (if not temporal synthesis, policy analysis, and (new or changed institutional arrangements that are relevant locally and acceptable in business, as well as at broader levels of government and geography. This has provided transferable outcomes that can contribute real options and adaptive capacity for suitable positive futures.

Standardised pre-hospital care of acute myocardial infarction patients: MISSION! guidelines applied in practice

NARCIS (Netherlands)

Atary, J. Z.; de Visser, M.; van den Dijk, R.; Bosch, J.; Liem, S. S.; Antoni, M. L.; Bootsma, M.; Viergever, E. P.; Kirchhof, C. J.; Padmos, I.; Sedney, M. I.; van Exel, H. J.; Verwey, H. F.; Atsma, D. E.; van der Wal, E. E.; Jukema, J. W.; Schalij, M. J.

2010-01-01

Background. To improve acute myocardial infarction (AMI) care in the region 'Hollands-Midden' (the Netherlands), a standardised guideline-based care program was developed (MISSION!). This study aimed to evaluate the outcome of the pre-hospital part of the MISSION! program and to study potential

Changes in myocardial perfusion due to physical exercise in patients with stable coronary artery disease

International Nuclear Information System (INIS)

Kendziorra, Kai; Foerster, Marcus; Sabri, Osama; Kluge, Regine; Walther, Claudia; Moebius-Winkler, Sven; Conradi, Katrin; Schuler, Gerhard; Hambrecht, Rainer

2005-01-01

Percutaneous transluminal coronary angioplasty (PTCA) is one of the main therapy options for patients with coronary artery disease (CAD), resulting in an improvement in myocardial perfusion and exercise capacity. Nevertheless, studies have also demonstrated a positive effect of regular exercise training on myocardial perfusion and maximum exercise capacity. The aim of this study was to evaluate changes in myocardial stress perfusion after 1 year of exercise training in comparison with the effects of PTCA in patients with CAD. In 66 male patients with angiographically confirmed significant coronary artery stenosis in one target vessel, myocardial perfusion scintigraphy was performed at baseline and 12 months after randomisation into either a physical exercise group or a PTCA group. Circumferential count rate profiles in 16 wall segments were classified according to their relative count rate and localisation within or outside the area supplied by the stenosed vessel. Ischaemic segments showed a significant improvement in myocardial count rate within the target area after 12 months in both the PTCA and the training group (PTCA group: from 76.8±4.9% to 86.6±10.9%, p=0.03; training group: from 74.0±7.3% to 83.7±10.8%, p<0.01). Outside the target area only the training group showed a significant improvement (from 77.7±4.4% to 91.7±4.8%, p<0.01). Our data indicate a significant improvement in stress myocardial perfusion in the training group after 12 months. The ischaemia is reduced not only in the target region of the leading stenosis but also in other ischaemic myocardial areas. In contrast, after PTCA stress perfusion improves only in the initially ischaemic parts of the target area. (orig.)

Myocardial SPECT in children with sickle cell disease

International Nuclear Information System (INIS)

Maunoury, C.; Hallaj, I.; Barritault, L.; Acar, P.; Montalembert, M. de

2002-01-01

Aim: While cerebral and bones strokes are well documented in children with sickle cell disease (SCD), impairment of myocardial perfusion is an unknown complication. Conventional techniques such as exercise testing and echocardiography have a low sensitivity and specificity to detect myocardial ischemia in patients with SCD. The aim of this prospective study was to assess myocardial perfusion with 201 Tl SPECT in children with SCD. Materials and Methods: Twenty-two patients, aged 12 ± 4 years, were included. Myocardial perfusion was assessed by 201 Tl SPECT after stress and 3 hours later after reinjection on a single head gammacamera equipped with a LEAP collimator (64x64 matrix size format, 30 projections over 180 0 , 30 seconds per step). Left ventricular ejection fraction (LVEF) was assessed by equilibrium radionuclide angiography at rest on the same day. Results: Myocardial perfusion was impaired in 13/22 patients: 8 had reversible defects and 5 had fixed defects. The left ventricular cavity was dilated in 13/22 patients. The mean LVEF was 63 ± 9%. There was no relationship between myocardial perfusion and left ventricular dilation or function. Conclusion: Myocardial perfusion is frequently impaired in children with SCD. Treatment with hydroxyurea should be considered in SCD patients with perfusion defects