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)

A series of 80 patients underwent continuous electrocardiography by Holter monitoring (ECG-H) for 24 hours to detect myocardial ischaemia. Fifty five patients were not on anti anginal therapy. The results of ECG-H were compared with those of exercise electrocardiography (ECG-E) (33 cases) and coronary angiography (50 cases). The ECG-H was positive in 31 of 43 patients (72%) with clinical (5 patients) or angiographic (38 patients) signs of ischaemic heart disease. The ECG-H was negative in 11 out of 12 patients (92%) with normal coronary; angiography. The sensitivity and specificity of ECG-H (57% and 92%) were inferior to those of ECG-E (75% and 100%) in the 33 untreated patients undergoing all three investigations. Twenty five recordings were compared with the ECG-E to assess anti anginal therapy. In asymptomatic patients ECG-H showed pathological ST depression in 10 cases, the ECG-E being positive in 1 7 cases. Anginal chest pain was induced on ECG-E in 5 out of 7 cases with a positive ECG-E and negative ECG-H. The lower sensitivity of the ECG-H compared to the ECG-E is related to several factors: 1) the sensitivity of the ECG-E increases with the number of exploratory electrodes; 2) reduced levels of physical activity decrease the sensitivity; in false negative cases the heart rate on ECG-H was only 74 +/- 7% of that corresponding to the threshold of positivity of the ECG-E, compared to 97 +/- 16% of the threshold heart rate in true positives (p less than 0,001); 3) the sensitivity of the ECG-H and ECG-E depends on the severity and distribution of the coronary lesions; false negative results were commoner in single vessel disease (57%) than in double or triple vessel disease (24%) (p less than 0,01). Anginal pain during the test increased the sensitivity to 92%. The specificity of the ECG-H is partially dependent on the recognition of positional variations of the ST segment. These were observed in 10% of cases but were generally easy to distinguish by their beat-to-beat appearances. The satisfactory specificity of the ECG-H in this study is also related to the high incidence of coronary artery disease in the population under study (80%). The predictive value of a positive test (Bayes theorem) was 97%, but that of a negative test was only 41%.
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PMID:[Value of continuous electrocardiographic recording using the Holter method in the diagnosis and surveillance of myocardial ischemia]. 678 40

The significance of silent myocardial ischemia detected by dipyridamole perfusion scintigraphy was evaluated in 80 patients with stable angina and reversible defects (RD) but no infarction. The patients were divided into two groups: 26 patients with silent RD (62 +/- 7 years) and 54 patients with painful RD (65 +/- 7 years). Coronary risk factors, extent of coronary lesions, localization and degree of RD, and prognosis were compared. There was no significant difference in the incidence of coronary risk factors between these two groups, except for hyperlipidemia which was less frequently observed in patients with silent RD than in those with painful RD (8% vs 41%, p < 0.01). Coronary angiography revealed a higher prevalence of insignificant lesions or single vessel disease in patients with silent RD than in those with painful RD (73% vs 39%, p < 0.05). Dipyridamole perfusion scintigraphy revealed a lower degree of RD in patients with silent RD than in those with painful RD (4.4 +/- 3.3 vs 9.0 +/- 4.1 segments, p < 0.05), though there was no significant difference in the localization of RD between these two groups. Treadmill stress testing revealed a lower incidence of chest pain in patients with silent RD than in those with painful RD (26% vs 65%, p < 0.05), despite the mean exercise-duration being significantly longer in the former than in the latter (5.5 +/- 1.7 vs 3.9 +/- 1.7 min, p < 0.05). There was no significant correlation between the late peak serum ML-1 level and LV volume, and the size and motion of infarcted areas in group B.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Significance of silent ischemia in dipyridamole perfusion scintigraphy: evaluation in patients with angina]. 766 46

The purpose of our study was to compare the ability of dobutamine and dipyridamole infusion to induce myocardial ischemia. In a population of 16 anesthetized open-chest swine, a coronary artery stenosis sufficient to abolish the hyperemic response to a 15-second total occlusion was created. Heart rate, systolic blood pressure, and dP/dt were recorded. Myocardial segment shortening was determined by sonomicrometry in all animals. In a subset of seven animals regional myocardial blood flow was measured by injection of radiolabeled microspheres. Dipyridamole was infused according to a high-dose protocol. After a washout period and reestablishment of a baseline state, dobutamine was infused incrementally. There was no significant difference between the baseline states. Dipyridamole did not affect heart rate but did significantly decrease blood pressure and rate-pressure product. Myocardial segment shortening decreased in the ischemic zone by 0.07 +/- 0.08 (p = 0.004). Dobutamine infusion significantly increased heart rate, blood pressure, and rate-pressure product. Myocardial segment shortening in the ischemic zone decreased by 0.17 +/- 0.09 (p < 0.001). Dobutamine decreased blood flow in the ischemic zone relative to baseline. Both dobutamine and dipyridamole infusion resulted in myocardial ischemia. The magnitude of the ischemic response is greater for dobutamine than for dipyridamole.
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PMID:Pharmacologically induced myocardial ischemia: a comparison of dobutamine and dipyridamole. 771 Jul 56

The use of pharmacologic stress testing for detecting and assessing ischemic heart disease (IHD) is reviewed. Methods of diagnosing IHD are designed to emulate conditions that increase myocardial oxygen demand in order to identify areas of ischemia and atherosclerotic lesions and to evaluate their functional or anatomical importance. Diagnostic methods can be divided into functional assessment with stress testing and anatomical assessment with coronary angiography. Physical stressors, such as exercise or atrial pacing, or pharmacologic stressors, such as vasodilators or beta-adrenergic-receptor agonists, can be used in stress testing. Electrocardiography, thallium planar scintigraphy, echocardiography, and other techniques are used to evaluate the response to stress testing. Unlike exercise stress testing, pharmacologic testing does not require physical exertion. Adenosine, dipyridamole, and dobutamine are the principal agents used in pharmacologic stress testing. Adenosine and dipyridamole mediate coronary artery vasodilation. Adenosine, a direct agonist, has a rapid onset and short duration of action. Dipyridamole, the only agent with approved labeling for use in stress testing, inhibits adenosine indirectly. Dobutamine increases cardiac output and heart rate as well as promoting coronary artery vasodilation. Clinical trials show that all three drugs can be used safely and effectively in patients after acute myocardial infarction or before vascular surgery and in individuals with risk factors for or symptoms of IHD. The sensitivity and specificity of pharmacologic stress testing for detecting IHD are at least as high as those of exercise testing. Minor adverse effects, including chest pain, headache, and facial flushing, are common, but major adverse effects are rare. Pharmacologic stress testing can be used in patients who cannot undergo exercise testing and offers a noninvasive alternative to coronary angiography.
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PMID:Pharmacologic stress testing: experience with dipyridamole, adenosine, and dobutamine. 816 Jun 85

The mechanisms responsible for the development of reversible thallium-201 (TI-201) defects with dipyridamole stress in patients with coronary artery disease (CAD) is not well understood. Previous experimental animal studies have demonstrated coronary steal characterized by an absolute decrease in subendocardial flow distal to a stenosis in response to dipyridamole infusion. Accordingly, the purpose of this study was to determine if reversible TI-201 defects in response to dipyridamole infusion are reflective of myocardial ischemia or secondary to regional differences in flow reserve. Dipyridamole (0.56 mg/kg) TI-201 imaging was performed in 23 patients in whom serial electrocardiographic, hemodynamic, aortic and coronary sinus lactate, and coronary sinus adenosine measurements were obtained. All patients with CAD had TI-201 redistribution (3.8 +/- 2.0 defects/patient), and all patients without CAD had normal scans. Mean aortic pressure was similar in both groups and did not change in response to dipyridamole (non-CAD 103 +/- 11 vs CAD 99 +/- 15 mm Hg, p = NS). Pulmonary capillary wedge pressure was similar at baseline (non-CAD 11 +/- 4 vs CAD 13 +/- 5 mm Hg, p = NS) and did not change in response to the drug (non-CAD 14 +/- 3 vs CAD 15 +/- 7 mm Hg, p = NS). Lactate extraction fraction was similar at baseline (non-CAD 0.22 +/- 0.09 vs CAD 0.17 +/- 0.14, p = NS) and decreased similarly in both groups (non-CAD 0.08 +/- 0.06 vs CAD 0.05 +/- 0.12, p = NS).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Hemodynamic and metabolic correlates of dipyridamole-induced myocardial thallium-201 perfusion abnormalities in multivessel coronary artery disease. 820 32

Dipyridamole and dobutamine stress were performed in the same 41 angiographically controlled patients. Both tests were followed by 2 dimensional-echocardiography. The dose of dipyridamole was 0.56 mg/kg/4 min. or 0.84 mg/kg over 10 min., while the dose of dobutamine was 10-20-30-40 and 40 micrograms/kg/min. over 3 min. each step. In addition, to reach the submaximal heart rate 0.25 mg/min Atropine was also injected for 4 minutes in 13 cases. One vessel disease was found in 15 cases, and 2 vessel disease was in 2 cases. The number of coronarography negative cases was 24. The sensitivity, specificity, positive and negative predictive values for both tests were 70%, 91%, 85% and 81%, respectively. False positive results were observed in 2 cases and false negative ones were found in 5 cases, mainly at left anterior descendent stenosis. There was a good agreement between the wall motion abnormality and the anatomic localization of stenoses. Both non-invasive tests are suitable for the diagnosis of ischaemic heart disease.
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PMID:[Comparative evaluation of dipyridamole and dobutamine 2-dimensional echocardiography in ischemic heart disease]. 829 72

We have verified the utility of echo-dipyridamole test in the diagnosis of chest pain of unsure origin, especially in patients who cannot be quickly submitted to exercise stress test because of permanent abnormalities at basal ECG or because of clinical reasons. 17 patients with chest pain, abnormalities at basal ECG not evolutive and insignificant for myocardial ischemia, absence of enzymatic curve, were admitted to our hospital from September 1988 to January 1990. All these patients were submitted before the ninth and fifteenth day of hospitalization to the echo-dipyridamole test. Drugs were discontinued 3 days before the test. Dipyridamole was administered intravenously in 4 minutes at dosage of 0.56 mg/kg during ECG and echocardiographic monitoring. If no ECG or echocardiographic changes were observed, a second intravenous bolus of dipyridamole at a dosage of 0.28 mg/kg in 2 minutes was made. After the end of infusion continuous ECG and echocardiographic monitoring was performed for 20 minutes at least. Blood pressure was controlled every 3 minutes. Only the major changes in segmental wall motion were considered for analysis to minimize possible errors. Moreover a second physician not present during the test, revised in following the wall motion changes of all the tests. The test was positive in 5 patients (29%) (positive group) and negative in 12 (71%) (negative group). The changes in the heart rate and blood pressure observed during the test were not significantly different in the two groups.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[The role of the echo-dipyridamole test in the differential diagnosis of chest pain]. 830 40

This study examined mainly the adverse effects of 201Tl myocardial scintigraphy with dipyridamole (D-Tl) in 73 elderly patients over 70 years old in comparison with those in 65 younger patients. Fifty-five of 73 elderly patients (75%) and 49 of 65 younger patients (75%) had a persistent or dipyridamole-induced perfusion defect on D-Tl. The hemodynamic changes induced by dipyridamole as well as the incidence of cardiac and noncardiac adverse effects were similar in both groups and no serious adverse effect occurred in either group. Secondly, we examined the procedure's usefulness for detecting ischemic heart disease in elderly and younger patients. Dipyridamole induced perfusion defect was noted in 21 elderly patients and in 24 younger patients (N.S.). Among the patients in whom coronary angiography was performed, significant coronary artery stenosis was found in 5 of 8 elderly patients and 17 of 20 young patients (N.S.). In patients with one or two-vessel disease, the area with dipyridamole induced ischemia was concordant with the stenotic area seen on coronary angiography in 3 of 3 elderly patients and 12 of 13 younger patients (N.S.). Thus, the safety and usefulness of D-Tl for detecting myocardial ischemia were comparable in elderly and young patients.
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PMID:Safety and accuracy of dipyridamole thallium myocardial scintigraphy in elderly patients. 841 31

Changes in electrocardiogram R-wave amplitude are often noted during treadmill stress testing. The two main reasons for this phenomenon discussed in the literature are left ventricular dimension changes and myocardial ischemia. To evaluate the relation between myocardial ischemia and electrocardiogram R-wave amplitude changes, we investigated in a retrospective study the data of 99 patients (20 females/79 males) with clinical signs of coronary artery disease. All patients had undergone exercise ECG and dipyridamole test. Electrocardiogram R-wave amplitude changes and ST-segment alterations were measured before, during and after provocation by bicycle stress test and intravenous dipyridamole. In neither test was there a specific reaction of R-wave amplitude to myocardial ischemia. During myocardial ischemia there were patients with an increase as well as a decrease R-wave amplitude. There was no significant correlation between the reaction of the R-wave amplitude in the exercise ECG when compared with the Dipyridamole test. Quantitative analysis showed a reduction of R-wave amplitude during maximum provocation in both tests, which was statistically significant in almost every subgroup of patients. In both tests the ST-segment depression was statistically significant in all groups, but there was no significant correlation between the reaction of R-wave amplitude and the ST-segment depression. In conclusion, there is no specific reaction of R-wave amplitude to myocardial ischemia. It is very unlikely, that the often noted changes in R-wave amplitude during stress testing are caused by ischemic episodes of the myocardium. Other mechanisms must be sought to explain the observed R-wave alterations.
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PMID:[Is there a specific response of the ECG R-wave amplitude to exercise-induced myocardial ischemia? Exercise test and dipyridamole test]. 845 60

We evaluated the usefulness of dipyridamole-thallium imaging for the detection of ischaemic heart disease in 257 patients with atherosclerotic vascular disease (80 patients with arteriosclerosis obliterans, 81 patients with aneurysm of the abdominal aorta, 60 patients with aneurysm of the thoracic aorta and 36 patients with dissecting aortic aneurysm). Clinical evidence of ischaemic heart disease was found in 69 of 257 (27%) patients, including 32 patients with arteriosclerosis obliterans, 23 with aneurysm of the abdominal aorta, 9 with aneurysm of the thoracic aorta and 5 with dissecting aortic aneurysm. Dipyridamole-thallium imaging identified myocardial ischaemia in 49 of 69 (71%) patients with clinical evidence of ischaemic heart disease. Dipyridamole-thallium imaging showed positive results in 67 of 81 (83%) patients with aneurysm of the abdominal aorta. In patients with no clinical evidence of ischaemic heart disease, the results of dipyridamole-thallium imaging were positive in 39 of 188 (21%) patients. Dipyridamole-thallium imaging was positive in 90 of the 257 (35%) patients as a whole. When we combined the patients with positive dipyridamole-thallium imaging with those with negative dipyridamole-thallium imaging but who had clinical evidence of ischaemic heart disease, 42% of all patients had evidence of ischaemic heart disease. Our findings suggest that atherosclerotic vascular disease is strongly associated with ischaemic heart disease and that dipyridamole-thallium imaging is useful for the detection of ischaemic heart disease.
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PMID:Usefulness of dipyridamole-thallium imaging in 257 patients with atherosclerotic vascular disease. 857 Jan 11


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