Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0151744 (myocardial ischemia)
 31,282 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To reveal possible factors that initiate ventricular arrhythmias (VA) in patients with coronary heart disease (CHD), a total of 44 patients with documented coronary artery stenosis were examined. The patients underwent coronary ventriculography, bicycle ergometry, 24-hour Holter monitoring, and examination of the autonomic nervous system (ANS). In 24 patients (Group 1), myocardial ischemic episodes were accompanied by VA. The latter were absent in myocardial ischemia in 20 patients (Group 2). In the two groups, there were no statistically significant differences in parameters, such as severity of atherosclerotic lesion of coronary arteries, total ejection fraction, existence of regional asynergy, exercise tolerance, number of daily myocardial ischemic episodes, their duration, degree of ST segment displacement. Increased activity of the sympathetic ANS was detected in 20 (83.3%) patients from Group 1 and only in 3 (15%) from Group 2 (p < 0.05). It is suggested that enhanced functional activity of ANS may be a prerequisite for displaying arrhythmogenic mechanisms in myocardial ischemia.
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PMID:[Ventricular arrhythmias in patients with ischemic heart disease: a possible role of the autonomous nervous system]. 803 34

Non-invasive evaluation of systemic hemodynamics during exercise in ischemic heart disease (IHD) was attempted by simultaneous measurement of cardiac output by the CO2 rebreathing method and indirect blood pressure in 44 males and 7 females with suspected IHD who underwent left ventriculography and coronary angiography. Thirty-nine of the 51 patients had abnormalities in the regional left ventricular systolic function (asynergy) and/or 75% or more stenosis of the major coronary arteries (IHD group). The other 12 patients were free of these findings, and injection of acetylcholine into the coronary arteries did not induce spasm. These patients were used as the control group. There were no differences in cardiac index (CI), mean blood pressure (MBP), or total peripheral resistance index (TPRI) at rest between the 2 groups. The IHD group had significantly lower CI (p < 0.01) and significantly higher TPRI (p < 0.05) during 25 and 50W exercise than the control group. There were no differences in MBP. A discriminant function using the change in CI (delta CI: l/min/m2) and the percent change in TPRI (% delta TPRI: %) during 25W exercise could predict IHD or control patients with probabilities of 82 and 83%, respectively. D = 3.66-1.39 x (delta CI)-6.67 x 10(-3) x (% delta TPRI), where D > or = 0.3 indicates IHD, and D < 0.3 indicates control. These results suggest that IHD patients have abnormal systemic hemodynamics during mild upright ergometer exercise, even though the resting hemodynamics are nearly normal.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Non-invasive evaluation of hemodynamics during mild upright exercise using the CO2 rebreathing method]. 804 93

New possibilities of quantitative evaluation of body surface potential mapping were studied in 78 patients with ischaemic heart disease. Integral maps of the Q wave, QRS and ST-T intervals were plotted and isochronous maps of ventricular activation time and maps of asynchronous potential minima of the Q wave were determined. Minimum and maximum potential values and their time relations were evaluated in the maps. Left ventricular contraction abnormality detected by left ventricular angiography was determined by a point score and expressed as an index of asynergy. The number of coronary artery branches with significant narrowing was assessed and the extent of coronary artery damage was evaluated by an arbitrary defined index. Using quantitative parameters from the maps, multiple stepwise linear regression was performed. The relationship between map parameters and index of asynergy corresponded to multiple correlation coefficient r = 0.69 (p = 0.01) in the whole group of patients. In the group of patients with left ventricular contraction abnormality the relationship between these parameters was found to be r = 0.87 (p = 0.01). The relationship between map parameters and the number of coronary artery branches with significant stenosis was r = 0.60 (p = 0.01) in the group of patients with positive coronary angiography. In the same group of patients the relationship between map parameters and the index evaluating coronary artery damage was equal to r = 0.63 (p = 0.01). The data obtained from body surface integral maps enable to quantify cardiac ischaemic damage.
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PMID:Quantitative evaluation of body surface potential mapping of heart electrical field in ischaemic heart disease. 821 31

To evaluate the role of dobutamine echocardiography for early assessment of myocardial viability and ischemia in acute myocardial infarction (MI), 59 patients with thrombolyzed acute MI underwent low- (5-10 micrograms/kg/min, 8 patients) and high-dose (20-40 micrograms/kg/min, 51 patients) dobutamine echocardiography at a mean of 8 +/- 4 days after acute MI. Myocardial viability in the infarct zone was documented in 43 of 59 (73%) patients (group 1), in whom mean asynergy score index decreased from 1.6 +/- 0.3 at baseline to 1.3 +/- 0.2 (p < 0.001), after low-dose dobutamine. No viability was present in 16 of 59 (27%) patients (group 2). At follow-up, recovery of regional contractile function was observed in group 1 (asynergy score index decreased from 1.6 +/- 0.3 to 1.4 +/- 0.3; p < 0.001), but not in group 2 patients. Sensitivity, specificity, and negative and positive predictive values of low-dose dobutamine echocardiography in predicting spontaneous recovery of function were 79%, 68%, 50%, and 89%, respectively. Of the 51 patients who underwent high-dose dobutamine, 26 of 36 (72%) group 1 patients showed a deterioration of contractility in the infarct zone indicative of myocardial ischemia compared with only 1 of 15 (7%) group 2 patients. At follow-up, recovery of regional function was greater in patients with no evidence of myocardial ischemia at high doses than in those with an ischemic response.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Dobutamine stress echocardiography for assessment of myocardial viability and ischemia in acute myocardial infarction treated with thrombolysis. 827 48

Intramyocardial fatty components are sometimes depicted by CT of the thorax. However, no studies have investigated the distribution, frequency and cause of these components by using statistical analysis. Three hundred forty-five patients with various cardiac diseases were examined with an ultrafast CT scanner, and intramyocardial fatty components were detected in 15 (4.3%) of them. The frequency of intramyocardial fatty components in each disease was as follows: 6% in ischemic heart disease, 7% in Kawasaki disease, 11% in hypertrophic cardiomyopathy (HCM), 18% in dilated cardiomyopathy (DCM) and 33% in arrhythmogenic right ventricular dysplasia (ARVD). Except for patients with HCM, the segments of the ventricles, where the fatty components were detected, agreed well with the segments with asynergy in left ventriculography and/or the segments with perfusion defect in T1 myocardial scintigraphy. Thus, ischemic fatty degeneration was considered to be a main factor in the production of intramyocardial fatty components in these diseases. The focus of arrhythmia was sometimes detected in the segments with intramyocardial fatty components in DCM and ARVD cases. It is suspected that intramyocardial fatty components sometimes produce arrhythmia in these diseases.
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PMID:[Detection of myocardial fatty components with ultrafast CT]. 844 98

The aim of the study was to assess the ability of dobutamine stress echocardiography to detect myocardial viability and ischemia in patients with acute myocardial infarction treated with thrombolysis and to correlate the acute response to dobutamine with late spontaneous functional recovery at follow-up. Forty-two consecutive patients with myocardial infarction treated with thrombolysis underwent low- (5 and 10 mcg/kg/min) and high-dose (20 to 40 mcg/kg/min) dobutamine stress echocardiography at a mean of 7 +/- 3 days of the acute phase. A follow-up 2D-echocardiogram was performed in all patients to evaluate the spontaneous recovery of function in the infarct area. On the basis of the response to the test, 3 groups of patients were identified: group 1 included 7 patients showing an improvement in left ventricular asynergy score index at low doses (from 1.5 +/- 0.3 to 1.3 +/- 0.2, p < 0.05) with no deterioration at high doses, indicative of myocardial viability without ischemia; group 2 (23 patients) showed a significant improvement in the asynergy index at low doses (from 1.58 +/- 0.3 to 1.32 +/- 0.32, p < 0.05) followed by a deterioration at high doses (1.68 +/- 0.4, p < 0.05 vs low-dose), suggestive of residual myocardial ischemia in the infarct zone; group 3 included 12 patients who showed no significant changes in the baseline asynergy score index (1.67 +/- 0.2) either at low or at high doses. The acute response to dobutamine stress echocardiography accurately predicted the spontaneous recovery of function in the infarct area at follow-up: both group 1 and group 2 patients showed a significant reduction in the asynergy score index (group 1: 1.16 +/- 0.3 vs 1.5 +/- 0.2, p < 0.001; group 2: 1.43 +/- 0.3 vs 1.58 +/- 0.3, p < 0.05), while group 3 had no recovery in the asynergy index (1.67 +/- 0.2 vs 1.67 +/- 0.2). Thus, in patients with acute myocardial infarction treated with thrombolysis dobutamine stress echocardiography can detect myocardial viability in 71% and ischemia in the infarct zone in 55% of patients; moreover, the response to the test during the acute phase is correlated with the degree of the late spontaneous recovery of function in the infarct area.
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PMID:Dobutamine stress echocardiography early after myocardial infarction treated with thrombolysis. Identification of myocardial viability and ischemia and relation to spontaneous functional recovery. 886 88

Aims of the study were to assess the usefulness of global and segmental myocardial contractility parameters detected during dipyridamole echocardiography test in diagnosis of ischaemic heart disease. Dipyridamole time (the time from the onset of dipyridamole infusion to development of asynergy) was also evaluated. The study included 97 patients with suspected or known ischaemic heart disease (32 patients after acute myocardial infarction), mean age 48.5 years. All patients underwent dipyridamole stress echocardiography and afterwards coronary angiography. Significant stenosis (< or = 70% lumen reduction in at least one major coronary vessel) was present in 52 (54%) patients-group I. Normal coronary arteries or no significant stenosis were found in 45 (46%) patients-group II. Significant increase of wall motion score index was observed in group I. No significant change with two and there vessels disease have shorter dipyridamole time than patients with one vessel disease. Significant decrease in ejection fraction during dipyridamole echocardiography test was found in group I, whereas not significant increase in ejection fraction was observed in group II. Dipyridamole echocardiography test is a sensitive, specific and well tolerated test in the diagnosis of ischaemic heart disease.
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PMID:[Echocardiographic analysis of segmental and global myocardial contractility after administration of dipyridamole in patients with ischemic heart disease]. 912 16

Myocardial perfusion scintigraphy with wall motion analysis is known to enhance accuracy in diagnosing ischemic heart disease. The purpose of this study is to determine the best method to evaluate regional wall motion in a gated planar perfusion study. Planar gated 99mTc tetrofosmin (GTF) study in two projections was performed after rest-exercise sequence SPECT studies (n = 29). To evaluate wall motion, cine-mode display, wall thickening, and inverted tetrofosmin studies including ventricular inner border tracing, segmental wall shortening and functional images were used. The results were compared with gated blood-pool (GBP) study in the same projections. In the GTF study, functional image identified asynergy significantly better than cinematic display. The best correlation between GTF and GBP studies was observed with functional images of phase and amplitude, with complete visual agreement seen in 145 of 168 (86%) segments. With quantitative analysis by means of regions of interest (n = 280), a good correlation was observed between GTF and GBP regarding regional amplitude (r = 0.78), regional phase (r = 0.84), average left ventricular phase (r = 0.91) and standard deviation of phase values (r = 0.90). The value for the count-based "ejection fraction" derived from inverted GTF showed insufficient correlation to that of the GBP study (r = 0.69). Functional imaging with myocardial perfusion imaging is a simple and effective means to evaluate ventricular asynergy. Similar diagnostic criteria to gated blood-pool imaging and comparable diagnostic accuracy are advantages of this approach.
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PMID:Functional imaging of gated Tc-99m tetrofosmin study as a simple method to quantify ventricular wall motion. 921 87

To assess the usefulness of the tissue Doppler imaging variables for the evaluation of left ventricular (LV) systolic function, we compared variables obtained by the pulsed Doppler method with the LV ejection fraction (%EF) and the maximum value for the first derivative of LV pressure (peak dP/dt). We examined 65 patients, including 15 patients with noncardiac chest pain, 15 with ischemic heart disease, 15 with dilated cardiomyopathy, 10 with hypertensive heart disease, and 10 with asymmetric septal hypertrophic cardiomyopathy. The subendocardial systolic wall motion velocity patterns were recorded for LV posterior wall and ventricular septum in the parasternal LV long-axis view. The peak dP/dt was significantly lower in the hypertensive heart disease, hypertrophic cardiomyopathy, and dilated cardiomyopathy groups. The peak systolic velocity was lower and the time from the electrocardiographic Q wave to the peak of the systolic wave for the posterior wall was longer in the hypertensive heart disease (5.9 +/- 0.5 cm/sec and 215 +/- 21 msec, respectively), hypertrophic cardiomyopathy (6.2 +/- 0.9 cm/sec and 217 +/- 17 msec, respectively), and dilated cardiomyopathy (5.2 +/- 0.8 cm/sec and 235 +/- 26 msec, respectively) groups than in the noncardiac chest pain (7.7 +/- 0.9 cm/sec and 187 +/- 24 msec, respectively) and the ischemic heart disease (7.6 +/- 0.8 cm/sec and 184 +/- 22 msec, respectively) groups. In all groups, the peak systolic velocity and the time from the electrocardiographic Q wave to the peak of the systolic wave for the posterior wall correlated directly and inversely, respectively, with the %EF (r = 0.59, p < 0.0001; r = -0.59, p < 0.0001) and the peak dP/dt (r = 0.75, p < 0.0001; r = -0.68, p < 0.0001). Both tissue Doppler variables for the ventricular septum did not correlate with the %EF but roughly correlated with peak dP/dt. We conclude that the systolic LV wall motion velocity parameters obtained by pulsed tissue Doppler imaging may be useful for noninvasive evaluation of global LV systolic function in patients with no regional asynergy.
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PMID:Assessment of left ventricular systolic wall motion velocity with pulsed tissue Doppler imaging: comparison with peak dP/dt of the left ventricular pressure curve. 961 16

During dobutamine stress echocardiography, ST-segment elevation developed in 20 of 372 patients (5%) without previous myocardial infarction and was associated with a transient severe asynergy of the myocardial region corresponding to the site of ST elevation. In 17 of 19 patients, ST-segment elevation was associated with a critical stenosis of the ischemia-related coronary artery, whereas in 2 of 19 patients with no critical lesions of the ischemia-related artery, coronary vasospasm was the most likely mechanism of myocardial ischemia.
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PMID:Dobutamine-induced ST-segment elevation in patients without myocardial infarction. 987 60


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