Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0002962 (angina)
 21,142 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Both nifedipine and nitroglycerin are used to treat angina pectoris. The comparative effects of these agents on myocardial blood flow and contraction in the setting of flow-limiting coronary stenosis are poorly understood. Thus 24 open chest dogs underwent carotid to left anterior descending coronary arterial perfusion with coronary flow probe and perfusion pressure monitoring. Segment length was measured with ultrasonic crystals in the subendocardial ischemic and nonischemic zones. Myocardial blood flow was measured with radioactive microspheres. Partial coronary occlusion was performed to attain a diastolic perfusion pressure of 40 mm Hg. Twelve dogs received intravenous nifedipine, 3 micrograms/kg per min, and 12 received intravenous nitroglycerin to reduce aortic pressure by 20 mm Hg. Partial occlusion resulted in a slight but significant decrease in segment shortening in the ischemic zone. Neither nitroglycerin nor nifedipine affected shortening in the ischemic zone. After occlusion, blood flow decreased in the subendocardial ischemic zone but was unchanged in the subepicardium. Nifedipine increased subendocardial blood flow in the nonischemic zone and decreased it in the ischemic zone but caused no change in subepicardial flow in the ischemic zone. In contrast, nitroglycerin decreased subendocardial and subepicardial blood flow in both the ischemic and nonischemic zones. In the setting of coronary stenosis, different classes of vasodilators may have varying effects on myocardial blood flow, suggesting different sites and mechanisms of action. In addition, segment function may not always reflect changes in myocardial blood flow.
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PMID:Comparative effects of nitroglycerin and nifedipine on myocardial blood flow and contraction during flow-limiting coronary stenosis in the dog. 680 19

A 41-year-old man developed persistent angina pectoris following blunt trauma to his chest. Three months after the injury coronary angiography demonstrated 80% obstruction of the mid-left anterior descending coronary artery. There was no evidence of atherosclerosis in the remaining coronary arteries. Therefore the assumption is made that blunt trauma can induce incomplete coronary occlusion resulting in classic angina pectoris in apparently otherwise normal coronary arteries. The suggested mechanism of injury to the coronary vessel is either intimal tear and/or subintimal hemorrhage with incomplete luminal thrombosis.
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PMID:Coronary artery obstruction due to blunt chest trauma with residual angina pectoris. 688 2

Prostacyclin, a substance produced by vessel wall, has a sustained vasodilating and platelet antiaggregating activity and therefore the variations in its production in patients with ischemic heart disease are of interest. Prostacyclin production was assessed in 59 patients with ischemic heart disease and 59 control subjects matched for age, sex, body weight, smoking habits, blood pressure and serum cholesterol levels. Of the 59 patients examined, 23 had had a myocardial infarction 3 to 12 months earlier; 21 had had spontaneous angina and 15 effort angina for at least 3 months. Patients with myocardial infarction and spontaneous angina were also classified in subgroups with and without acute coronary insufficiency, according to the occurrence of ischemic attacks in the week preceding the study. Both circulating prostacyclin levels and prostacyclin produced after 3 minutes of ischemia were measured by bioassay. Circulating prostacyclin was significantly less in patients with ischemic heart disease than in matched control subjects independent of the clinical type of ischemic heart disease. Circulating prostacyclin was particularly reduced in patients with acute coronary insufficiency in comparison to patients without, both in the group with myocardial infarction (1.11 +/- 0.22 ng/ml and 2.09 +/- 1.32, respectively) and in the group with spontaneous angina (1.24 +/- 0.42 and 2.17 +/- 1.16, respectively). No differences could be found for prostacyclin produced after 3 minutes of ischemia in relation to the presence of acute coronary insufficiency. The lower level of prostacyclin production in patients with ischemic heart disease and especially in those with acute coronary insufficiency may be an important factor in the occurrence of coronary occlusion or spasm.
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PMID:Reduced prostacyclin production in patients with different manifestations of ischemic heart disease. 703 88

The association of myocardial infarction with normal coronary arteries was analyzed prospectively. A series of 259 consecutive men aged 60 years or less underwent selective coronary angiography 30 days after a definite infarct. Coronary arterial lesions were documented in 251 patients, normal coronary arteries in the remaining 8. The latter patients had a significantly lower (p less than 0.001) mean age than the former; no patient older than 50 years had patent coronary arteries, whereas 5 of the 11 patients under age 35 had normal arteries. The prevalence of risk factors was similar in both groups of patients. Although there were no group differences in infarct size or location, patients with normal coronary arteries had a higher ejection fraction (p less than 0.01) and a lower left ventricular end-diastolic pressure (p less than 0.05). A previous history of angina or infarction and the occurrence of new coronary events were confined to patients with coronary arterial lesions. The clinical course of patients presenting with normal angiograms was uneventful. Transient coronary occlusion, the most likely mechanism of infarction in this group of patients, could not be ascribed to either spasm or platelet hyperactivity.
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PMID:Myocardial infarction with normal coronary arteries: a prospective clinical-angiographic study. 724 44

Exercise and redistribution myocardial scintigraphy using thallium-201 was compared with the left ventricular angiogram and with the presence of stenosis or occlusion of coronary arteries on angiography. Irreversible scintigraphic defects representing areas of myocardial infarction were found in all patients with occlusion of the left anterior descending artery but nearly one-third of patients with stenosis of that artery also showed evidence of infarction. For the right coronary or circumflex arteries the incidence of infarction was 82% with vessel occlusion and 57% with vessel stenosis. Of abnormally contracting segments on the left ventricular angiogram, 95% showed irreversible scintigraphic defects but 33% of normally contracting segments supplied by a diseased artery also showed this. Myocardial infarction is not uncommon in patients with angina even in the absence of coronary occlusion. The incidence is underestimated by the left ventricular angiogram. These findings are of importance in the assessment of patients with coronary disease and their evaluation before coronary artery surgery.
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PMID:Effect of stenosed and occluded coronary arteries on immediate and late myocardial uptake of thallium-201. 727 29

We evaluated the effects of antecedent anginal episodes and coronary artery stenosis on left ventricular function during coronary occlusion and the role of collateral filling in 33 patients with angina pectoris who underwent angioplasty. Wall motion abnormalities were investigated by echocardiography and classified into hypokinesia and akinesia. Collateral filling during angioplasty was evaluated by using a second artery catheter. Akinesia was observed as follows: 24% of the patients had > 30 anginal episodes, 38% had 5 to 30, and 87% of the patients had < 5 (p < 0.01); 12% of patients had a lesion of 99%, 47% had a lesion of 90%, and 83% had a lesion of 75% (p < 0.05). Akinesia was observed in none of the patients with grade 3 collaterals, 57% with grade 2, and 67% with grade 1 or 0 (p < 0.01). These observations suggest that the patients with antecedent frequent anginal episodes and severe coronary stenosis have less left ventricular dysfunction during coronary occlusion. This finding may be the result of more extensive collateral development.
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PMID:Effects of antecedent anginal episodes and coronary artery stenosis on left ventricular function during coronary occlusion. 763 2

Patients with a chronic coronary occlusion often undergo coronary angiography after weeks to months of occlusion. The published reports underestimate the extent of this problem because such patients are often arbitrarily assigned to receive medical therapy or undergo bypass surgery as a result of poor success with percutaneous revascularization and substantial restenosis. Thus, there is controversy about the role of angioplasty in this patient cohort. The goal of this overview was to evaluate the available information about angioplasty in chronic coronary occlusions. The primary indication for attempted recanalization of a chronic coronary occlusion has been symptomatic angina pectoris. Anginal status often improves after successful procedures (70% vs. 31% with a failed procedure); left ventricular function may improve; and subsequent referral for coronary artery bypass graft surgery is uncommon (3% vs. 28% in unsuccessful cases). Successful recanalization is achieved in approximately 65% of attempted procedures. Inability to cross the stenosis with a guide wire is the most common cause of procedural failure. Statistically significant predictors of procedural success include older occlusions (75% < 3 months old vs. 37% > or = 3 months old), absence of any anterograde flow through the occlusion (76% with vs. 58% without), angiographically abrupt-appearing occlusions (50% vs. 77% with tapered occlusions), presence of bridging collateral vessels (23% with vs. 71% without) and lesions > 15 mm. Procedural complications occur at a slightly lower incidence than in angioplasty of high grade subtotal stenoses. Long-term success is limited, and restenosis can be expected in > 50% of the patients. The experience with chronic total occlusions of saphenous vein bypass grafts is small, but there appear to be limited procedural success and significant procedural complications, particularly associated with distal emboli. The role of new pharmacologic agents has yet to be defined and that of new devices has been disappointing so far, but further technologic advances are on the horizon.
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PMID:Percutaneous revascularization of chronic coronary occlusions: an overview. 779 37

Percutaneous transluminal coronary angioplasty can be performed safely and effectively in patients with chronic total coronary occlusion. To investigate the effect on left ventricular function, global and regional left ventricular ejection fraction were analyzed by contrast angiography in 49 patients before and 10 +/- 6 weeks after successful recanalization. Coronary angiography at follow-up showed reocclusion in 12 patients (24%). In 37 patients with patent arteries global ejection fraction increased from 55.8 +/- 7.1% at baseline to 62.5 +/- 11.3% at follow-up (P < 0.001), and regional wall motion assessed by the centerline method improved from -1.7 +/- 1.0 to -0.6 +/- 1.5 standard deviations/chord (P < 0.001). In contrast, in patients with reocclusion neither global ejection fraction nor regional wall motion were significantly different at follow-up compared with baseline. Changes in global or regional left ventricular function after coronary recanalization were unrelated to other parameters such as severity of angina, duration of occlusion, history of myocardial infarction, presence or absence of visible collaterals, or baseline left ventricular function. Thus in patients with primarily successful recanalization of chronically occluded coronary arteries persistent vessel patency is the major determinant of global and regional improvement of left ventricular function.
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PMID:Improved global and regional left ventricular function after angioplasty for chronic coronary occlusion. 795 Jan 55

Acute coronary occlusion can occur following percutaneous transluminal coronary angioplasty (PTCA) upon return to the coronary care unit (CCU), and is sometimes life-threatening. To identify high-risk patients for acute occlusion following PTCA, we analyzed 11 patients with post-lab acute occlusion. All of the patients had some evidence of intimal tear or dissection at the site of dilatation. During the study period, 1343 patients (1998 lesions) with angina pectoris underwent PTCA. Of these, 331 vessels (17%) had some degree of intimal tear or dissection at the site of dilatation. From these 331, 50 patients (50 vessels) without evidence of acute occlusion were randomly selected to serve as the control group. Patients in the acute occlusion group had more extensive dissection (p < 0.05) and less water balance (drip-infused water-urine, ml) during angioplasty (p < 0.1) than those in the control group. Furthermore, a significantly higher percentage of patients in the acute occlusion group complained of chest discomfort upon arrival at the CCU (72% vs 8%, p < 0.0001). These variables may be useful in identifying high-risk patients for post-lab acute occlusion, particularly in the presence of an intimal tear or dissection at the target site.
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PMID:Risk factors for the development of post-lab acute coronary occlusion following successful percutaneous transluminal angioplasty. 796 96

Previous studies have assessed the determinants of collateral vessel recruitment during coronary occlusion in patients undergoing percutaneous transluminal coronary angioplasty (PTCA). However, the determinants of severity of myocardial ischemia after sudden coronary occlusion do not necessarily coincide with those responsible for collateral vessel recruitment. The aim of this study was to assess the determinants of severity of myocardial ischemia during balloon inflation by recording surface and intra-coronary electrocardiograms (ECGs). In 62 consecutive patients with 1-vessel disease and without previous myocardial infarction undergoing successful PTCA for stable (n = 33) or unstable (n = 29) angina pectoris, the summation of the absolute values of ST-segment shifts from baseline on the intracoronary and surface ECG at the end of the first 2-minute inflation was obtained as an index of the severity of myocardial ischemia. Stenosis severity before PTCA was measured using computerized coronary angiography, while the grade of collateral filling was scored according to Rentrop's classification. The mean (+/- 1 SD) ST-segment shift at the end of balloon inflation was less in patients with than without collateral vessels (12 +/- 10 vs 23 +/- 15 mm, p < 0.05). Despite a similar prevalence of collateral vessels (34% vs 24%, p = NS), the mean ST-segment shift was also less in patients with unstable than stable angina (15 +/- 9 vs 24 +/- 17 mm, p < 0.05). However, the mean ST-segment shift was not associated with the severity of coronary stenosis before PTCA (r = 0.0004, p = NS).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Determinants of myocardial ischemia during percutaneous transluminal coronary angioplasty in patients with significant narrowing of a single coronary artery and stable or unstable angina pectoris. 797 64


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