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)

Coronary hemodynamic responses to transient coronary artery occlusion in 21 patients were investigated by using regional coronary venous thermodilution to measure regional coronary venous flows. Transient coronary artery occlusion was produced by coronary artery spasm (13 patients) or balloon inflation during coronary angioplasty (8 patients). The left anterior descending coronary artery was transiently occluded in 12 patients, the right coronary artery in 8 patients and the left circumflex artery in 1 patient. During transient coronary occlusion, regional venous flow decreased in 20 of the 21 patients (79 +/- 31 to 53 +/- 29 ml/min, mean +/- standard deviation [SD]; probability [p] less than 0.05) corresponding to the left ventricular region perfused by the occluded artery. Regional coronary resistance increased in all 21 of these regions (1.42 +/- 0.75 to 2.26 +/- 1.45 mm Hg/ml per min, p less than 0.05). Simultaneously measured blood flow and resistance in the left ventricular region supplied by the nonoccluded arteries did not change significantly (62 +/- 27 to 64 +/- 29 ml/min and 1.85 +/- 0.93 to 1.81 +/- 0.98 mm Hg/ml per min, respectively). Coronary hemodynamic changes were similar during transient coronary occlusion, whether produced by coronary spasm or by balloon inflation. However, the presence of angina, reversible electrocardiographic abnormalities and an increase of the left ventricular filling pressure were more common during coronary spasm (p less than 0.05 for all). Regional coronary hemodynamic changes during transient occlusion of the anterior descending, circumflex or right coronary artery were similar. These data show that coronary occlusion decreases regional left ventricular flow in the region perfused by the affected artery. The method of coronary occlusion or the coronary artery affected during occlusion did not seem to elicit different responses.
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PMID:Regional coronary venous flow responses to transient coronary artery occlusion in human beings. 622 3

Controlled crushing of the intimal plaque and of the underlying vessel wall are the determinants of transluminal dilatation of coronary stenoses. The technique of angioplasty has been recently modified in many laboratories, by the use of new catheters and dilatation policies. Data from the NHLBl Registry indicate a 59% primary success rate, being 29% and 12% respectively the failures due either to inability to cross or to dilate the stenosis. A retrospective analysis of successful procedures has highlighted factors that positively affect the results: recent onset of the angina, lack of calcifications, iterative ballooning at high pressures and the experience of the angiographer. Main complications were angina becoming unstable (5.7%) and acute coronary occlusion (4.4%); an emergency bypass operation had to be done in 6.3% of the cases, whereas myocardial infarctions scored 4.4% and hospital deaths less than 1%. Preliminary results of Centro De Gasperis concern 18 attempts to dilate LAD stenoses: primary success rate was 44% with a failure rate of 39% and 17% regarding inability to cross or only to dilate stenosis, respectively. The above results are less favorable than those reported in NHLBl Registry and very much less than those reported by selected laboratories; they are however acceptable in view of the suboptimal characteristics of the materials used and the limited experience of the team.
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PMID:[Transluminal coronary angioplasty. Technic and immediate results]. 622 15

The frequency and outcome of emergency CABG for complications of PTCA in the NHLBI PTCA Registry were analyzed. Emergency surgery was performed in 202 patients (6.6%). The most frequent indications for emergency operation were coronary dissection in 46%, coronary occlusion in 20%, prolonged angina in 14% and coronary spasm in 11%. Emergency surgery was most often necessary in patients in whom lesions could not be reached or traversed, but more than 25% of patients who required emergency surgery had initially successful dilatation followed by abrupt reclosure of the vessel. The mortality rate with emergency CABG was 6.4%, and nonfatal MI occurred in 41% of patients, with Q waves developing in approximately 60% of patients with MI. However, 53% of patients managed with emergency CABG for severe ischemic events with PTCA did not have evidence of MI or die and had an uncomplicated postoperative course. No baseline clinical predictors of emergency surgery were identified. Lesion eccentricity was associated with a significant increase in frequency of emergency operation, and the incidence of emergency surgery declined with increasing experience with PTCA.
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PMID:Emergency coronary bypass surgery after coronary angioplasty: the National Heart, Lung, and Blood Institute's Percutaneous Transluminal Coronary Angioplasty Registry experience. 623 81

The effects of relative contraindications on the immediate results of PTCA were investigated in 1,939 patients, and on long-term results in 998 patients with isolated stenosis of 1 coronary artery. Immediate results subjected to analysis were: success rate, major complications (coronary occlusion, MI and death) and emergency CABG. The analysis of long-term results included: status of angina pectoris, occurrence of MI, restenosis, repeat PTCA, CABG and death. Unstable angina and previous MI had no negative effects on immediate results, whereas a significantly lower success rate was noted in patients with angina for more than 1 year compared to patients with angina of shorter duration (p less than 0.05) and patients older than 60 years compared with younger patients (p less than 0.01). During follow-up, patients with unstable angina had higher CABG rate (p less than 0.01); the other relative clinical contraindications to PTCA did not exert adverse effects. Angiographically, there was a lower immediate success rate in patients with nonproximal stenosis (p less than 0.001) and in patients with calcium in the affected artery (p less than 0.01) and at the site of stenosis (p less than 0.001). Patients with tubular or diffuse stenoses had similar success rates but higher rates of complications, excluding death, than those with discrete stenoses (p less than 0.01). Patients with eccentric stenoses had a lower success rate and a higher rate of complications and emergency CABG than patients with concentric stenoses (p less than 0.001 for all 3 variables).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Percutaneous transluminal coronary angioplasty (PTCA) in patients with relative contraindications: results of the National Heart, Lung, and Blood Institute PTCA Registry. 623 95

The biology of the myocardium was studied under experimental conditions similar to angina pectoris. In some dogs the myocardium was adapted to ischaemia by progressive coronary occlusion of 1-5 min followed by restoration of circulation during 5 min. In other dogs adaption was followed by 20 to 35 min ischaemia. The animals were sacrificed immediately or after 2-10 days. Transient ischaemia produced less severe alterations then abrupt coronary obstruction. Adaptation followed by 20 and 35 min ischaemia induced foci that undergo cytolysis and scarring of maximum intensity on the 8th day. Activity of enzymes in the mitochondrial suspension, especially of cytochromoxidase, decreases and lysosomal hydrolases increase with focal necroses.
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PMID:Experimental studies in transient myocardial ischaemia. 630 Dec 25

A transient complete coronary occlusion due to spasm was induced by the cold pressor test in a 51-year-old man with variant angina. Arteriography before the test revealed a normal left coronary artery and only minor irregularities of the mid-portion of the right coronary artery. Three minutes after cold stimulation, angina pectoris accompanied by ST-segment elevation was observed in lead II ECG. Simultaneous coronary arteriography during the attack showed a complete occlusion of the proximal right coronary artery due to spasm. The anginal attack together with spastic occlusion disappeared after administration of 0.8 mg of nitroglycerin. Thus, the cold pressor test can trigger coronary artery spasm and may even lead to a total occlusion in patients with variant angina. Individuals with variant angina may be subjected to additional risk when exposed to cold temperatures.
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PMID:Cold pressor test and variant angina. 640 50

We reviewed the records of 44 dialysis patients who had undergone one or more coronary angiograms to determine the frequency with which symptomatic ischemic heart disease (IHD) and significant coronary artery narrowing coincided and to determine those factors which were associated with the coronary atherosclerotic process. Thirty-four patients were catheterized for angina pectoris or myocardial infarction. Of this group, 53% were found to have significant narrowing of coronary arteries. This group was older than the group with trivial or no coronary artery occlusion and their duration of dialysis was shorter. All the patients with significant coronary occlusion were white and the majority were adult males. Discriminant function analysis revealed that the presence of significant coronary artery occlusion could be predicted with high sensitivity and specificity by the following variables: older age, white race, male sex, the presence of symptomatic IHD prior to the onset of dialysis, increased total serum cholesterol, abnormal left ventricular wall motion, and reduced alkaline phosphatase. We also found that the occurrence of symptomatic IHD far exceeded the presence of significant atherosclerotic coronary artery narrowing. We suggest that this may result from several dialysis-associated alterations in oxygen delivery and myocardial oxygen consumption.
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PMID:Dialysis-associated ischemic heart disease: insights from coronary angiography. 648 69

The calcium flux inhibitors nifedipine and verapamil have recently been used in the setting of both classical Heberden's and variant angina. It has also been suggested that these agents may preserve function and viability of threatened myocardium. The effects of these agents on the relationship between myocardial blood flow and contraction in the setting of partial coronary occlusion is unknown. Thus 39 open-chest dogs underwent partial coronary occlusion to diastolic perfusion pressures of 25 or 40 mm Hg. The dogs then received intracoronary infusions of 10 micrograms nifedipine or 100 micrograms verapamil. Myocardial blood flow was measured with tracer microspheres and myocardial shortening was assessed with ultrasonic crystals. At 25 mm Hg nifedipine improved myocardial shortening while blood flow did not change. In contrast, verapamil caused shortening to be abolished but also did not change blood flow. At 40 mm Hg nifedipine, while not affecting shortening, caused a "redistribution" of blood flow from endocardium to epicardium; in contrast, verapamil again caused shortening to be abolished, but only increased epicardial blood flow leaving endocardial flow intact. Thus verapamil and nifedipine have differing effects. Nifedipine is a potent vasodilator at doses having no negative inotropic effects. In addition, nifedipine can cause a transmural "redistribution" of blood flow from endocardium to epicardium. In contrast, verapamil is also a potent vasodilator, but has profound negative inotropic effects.
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PMID:Contrasting effects of nifedipine and verapamil on myocardium and vascular smooth muscle at two levels of coronary occlusion in the dog. 665 Mar 56

Thrombotic coronary artery occlusion is now recognized as the usual cause of acute myocardial infarction. The thrombus usually forms at the site of intimal disruption over an atherosclerotic plaque. Following coronary occlusion, myocardial necrosis begins within 40 minutes in the subendocardium and progresses outward toward the epicardium over the next several hours. The intracoronary infusion of streptokinase will produce lysis of the occluding thrombus in up to 80% of patients. It appears that reperfusion with streptokinase in the first few hours following the onset of the myocardial infarction produces a small increase in late left ventricular function, though ECG and enzyme evidence of acute myocardial infarction are not prevented. The improvement in left ventricular function is variable from patient to patient and has not been demonstrated in all the randomized studies to date. The time limit for myocardial salvage may not be the same in all patients. The greatest benefit is probably achieved with reperfusion in the first 4-6 hours, although some benefit may occur as late as 18 hours after the onset of infarction. Many patients who receive intracoronary infusion of streptokinase develop a systemic lytic state, though serious bleeding complications in carefully selected patients are infrequent. High-dose IV streptokinase is easier, cheaper, and quicker to initiate than intracoronary streptokinase but is probably less effective than the intracoronary route in producing rapid lysis of the occluding coronary thrombus. The optimal dose and rate of administration of IV streptokinase have not been determined. The final role and ultimate benefit of thrombolytic therapy of myocardial infarction have not yet been determined, but some of the issues may be clarified by the larger randomized trials now under way. It appears, at present, that the use of intracoronary streptokinase may have a role in the treatment of selected patients with acute myocardial infarctions in institutions with the facilities and the personnel necessary to perform this procedure safely. In the future, thrombolytic therapy may also have a place in the treatment of selected patients with unstable angina and post-myocardial infarction angina. The future availability of more selective thrombolytic agents may make the early IV therapy of myocardial infarction a safer, more effective option and expand the indications for thrombolytic therapy.
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PMID:Thrombolytic therapy of acute myocardial infarction. 666 25

The authors report a case of threatened spread occurring 4 days after posterior-inferior myocardial infarction and involving the same territory. The spontaneous occurrence during coronary angiography of an occlusive spasm of the right coronary artery with recurrence of angina and ST elevation in the area of initial necrosis suggests that this mechanism might be the contributory factor to the threat of in situ spread. Thus intermittent coronary occlusion from repeated spasm can bring about incomplete necrosis of the area of dependent myocardium and by extension threaten the viability of groups of still healthy cells. A syndrome of this kind initially requires coronary-dilating medical treatment, with nitrate derivatives and calcium inhibitors and then early coronary angiography with the use of pharmacodynamic tests to assess the suitability of surgery.
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PMID:[Threatened extension of myocardial infarction in situ and coronary spasm]. 671 26


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