PubMed Health⌕ Search

Biomedical subjects

D S Baim

Publications and source records attributed to D S Baim.

212 records · Page 12Linked to original sources
PubMed1983

Myocardial infarction in patients with coronary artery spasm demonstrated by angiography.

Twelve cases of myocardial infarction (MI) were documented in 11 of 39 patients who had coronary artery spasm (CAS) that was observed by angiography either before MI (3 patients), after MI (5 patients), or both before and after MI (3 patients). MI corresponded in location to sites of ECG changes of myocardial ischemia during spontaneous angina pectoris in 7 of 7 patients and to the region of myocardium supplied by the vessel in which CAS was observed by angiography in each patient. MI occurred in the distribution of the right coronary artery in 8 patients and of the left coronary artery in 4 patients. Of 12 vessels that supplied infarcted regions of myocardium, 7 vessels had greater than or equal to 50% diameter fixed coronary artery narrowing (CAN), but the remaining 5 vessels had minimal (10%) or no fixed CAN. In those patients who were studied after MI, coronary angiography demonstrated that only 3 of 9 vessels in the distribution of infarcted regions of myocardium were completely occluded. Clinical follow-up for an average of 1.3 years after MI showed that 7 patients continued to have chest pain, 2 patients were asymptomatic, and 2 patients died suddenly 9 weeks and 1 year, respectively, after MI. Therefore, among our patients with CAS demonstrated by angiography, MIs (1) were frequent (28%), (2) occurred in the distribution of observed coronary spasm, (3) were frequently (5 of 12 arteries) in the distribution of vessels having minimal or no fixed narrowing, and (4) were often (6 of 9 arteries) in the distribution of vessels that were demonstrated to be patient after MI.

Adult↗
PubMed1982

A new catheter system for coronary angioplasty.

A new catheter system has been designed for percutaneous transluminal coronary angioplasty. An independently movable, flexible-tipped guide wire within the balloon dilation catheter facilitates selection of the involved vessel. This guide wire can be passed slowly and carefully beyond the coronary stenosis, permitting safe advancement of the balloon catheter. After testing in animal and cadaver hearts, this system was used in 53 patients (56 stenoses) with single vessel coronary artery disease, with an overall primary success rate of 64 percent. In the last 41 of these 56 cases, use of a balloon catheter with a smaller deflated diameter increased the success rate to 73 percent. In patients with lesions of the left anterior descending coronary artery, the success rate was 89 percent. Three (6 percent) of the 53 patients had complications during coronary arterial dilation that necessitated emergency coronary arterial bypass graft surgery. There were no procedure-related or late cardiac deaths. During the mean follow-up period of 8 months (range 1 to 21), there were one late death (of noncardiac causes) and no late myocardial infarctions. Clinical status was persistently improved in 31 of the 36 patients who had successful dilation. The remaining five patients experienced restenosis at the angioplasty site and return of angina pectoris within 3 months of dilation. Two of these patients had repeat coronary angioplasty with restoration of asymptomatic status, and three had elective coronary bypass graft surgery.

Angioplasty, Balloon↗
PubMed1982

Coronary spasm associated with urticaria: report of a case mimicking anaphylaxis.

Recent investigations suggest that the vasoactive substances, histamine, prostaglandin E2, and thromboxane A2 are mediators of coronary artery spasm. These substances may be released during a episode of urticaria. We report here a case of coronary artery spasm associated with an episode of acute urticaria. The coronary spasm may have been mediated by the vasoactive substances released from basophils and secondary platelet aggregation, known to occur with urticaria.

Acute Disease↗
PubMed1982

Percutaneous transluminal coronary angioplasty: analysis of unsuccessful procedures as a guide toward improved results.

Technical success in percutaneous transluminal coronary angioplasty (PTCA) is a function of patient selection, operator experience, and the capabilities of the angioplasty equipment employed. When unsuccessful PTCA occurs, it is the result of one of several factors: (1) a failure to cross the stenosis; (2) a failure to dilate the stenosis; (3) an ischemic complication; or (4) a late recurrence of the anginal syndrome. In this paper, we discuss the relative frequency of these types of failure, and the ways in which improvements in technique and/or equipment may be employed to improve the chance of a successful procedure.

Angina Pectoris↗
PubMed1982

Simultaneous measurement of coronary venous blood flow and oxygen saturation during transient alterations in myocardial oxygen supply and demand.

Continuous simultaneous measurements of coronary venous oxygen saturation and coronary venous blood flow were performed in 10 open chest dogs and 13 conscious human patients, using a combination of fiberoptic oximetry and thermodilution. Measurements were made during transient coronary arterial occlusion and during the intracoronary administration of nitroglycerin or isoproterenol. Two patterns of coronary vasodilation were distinguished: in primary (demand-independent) vasodilation, both coronary flow and coronary venous oxygen saturation increased, while myocardial oxygen consumption remained constant. In secondary (autoregulatory) vasodilation, coronary flow increased as coronary venous oxygen saturation decreased, corresponding to an increase in myocardial oxygen consumption. These observations could not have been made if either coronary venous blood flow or oxygen saturation had been measured alone; thus, this investigation demonstrates the utility of this combination of techniques in the study of the coronary circulation.

Animals↗
PubMed1982

The effects of diltiazem and reduced serum ionized calcium on ischemic ventricular fibrillation in the dog.

Calcium influx blockers reportedly suppress ventricular arrhythmias during acute ischemia. We therefore studied the effects of diltiazem and reduced serum ionized calcium on ventricular fibrillation (VF) in a reversible ligation model. VF was produced at 15-minute intervals by simultaneous occlusion of the left anterior descending and circumflex arteries of 31 dogs. Time from coronary occlusion to onset of VF showed no significant variation during 15 consecutive trials in six dogs that received saline alone. Intravenous infusion of diltiazem (0.02 mg/kg per min) markedly delayed the onset of VF in each of 10 dogs (P less than 0.0001). Mean VF latency increased from 138 to 295 seconds during a 45-minute diltiazem infusion, declined exponentially when the infusion ceased, and was strongly correlated with serum diltiazem concentration (r = 0.96, P less than 10(-6)). In five dogs, hemodynamic measurements, including coronary venous blood flow, were performed during each occlusion. The increase in VF latency by diltiazem was not due to increased coronary flow during occlusion or to reduction of left ventricular (LV) mechanical work. In six dogs, mean serum ionized calcium, [Ca++], was reduced from 1.11 to 0.59 mM by infusion of sodium citrate. Citrate infusion increased mean VF latency from 155 to 243 seconds, and the increase observed in each dog was correlated (r = 0.84, P less than 10(-6)) with the reduction in [Ca++]. VF latency was unaffected by lidocaine in nine dogs. The antifibrillatory effect of diltiazem during global LV ischemia may be an electrophysiological phenomenon related to reduction of cellular calcium influx.

Animals↗
PubMed1981

Histamine provocation of clinical coronary artery spasm: implications concerning pathogenesis of variant angina pectoris.

Twelve patients with nonexertional chest pain and nonobstructive fixed coronary disease (less than 50% luminal diameter narrowing) were given histamine to investigate the potential role (coronary artery H1 receptor agonism) of the endogenous agent in producing coronary artery spasm (CAS). Histamine, at intravenous dose of 0.5 to 1.0 microgram/kg/min, provoked CAS in four patients. In six patients neither histamine nor ergonovine provoked spasm, and these patients were considered by chronic follow-up evaluation to have noncardiac etiology for their chest pain syndrome. In one patient CAS was provoked with ergonovine but not by histamine, and one ergonovine-positive patient had an equivocally positive histamine result. Pretreatment with cimetidine (H2 receptor antagonism) was necessary to avoid unpleasant side effects of histamine. Thus these observations indicate that histamine should be included among the specific agents capable of inducing CAS and provide new insight concerning the mechanism(s) causing variant angina pectoris.

Adult↗
PubMed1981

Platelet activation in clinical coronary artery disease and spasm.

Current concepts of atherogenesis, based on animal models, suggest a role for platelets in the development of atherosclerotic lesions, possibly through the release of alpha granule constituents. Platelets may also contribute to the development of vascular spasm through thromboxane A2 production. Platelet activation in the coronary circulation in patients with coronary artery disease (CAD) should occur if these hypotheses apply clinically. We measured aortic and coronary sinus plasma levels of the platelet alpha granule constituent beta-thromboglobulin (B-TG) and thromboxane B2 (TX B2) by radioimmunoassay in 15 patients with severe atherosclerotic CAD, seven patients with angiographically normal coronaries, and five patients undergoing evaluation for coronary artery spasm (CAS). Compared with the controls, CAD patients had significantly greater transmyocardial release of B-TG (11.1 +/- 8.1 ng/ml, mean +/- SEM vs 62.5 17.2, p less than 0.05 by rank sum test); TX B2 gradients showed a similar trend but the difference was not statistically significant (-0.08 +/- 0.03 ng/ml vs 0.22 +/- 0.02, 0.05 less than p less than 0.10). Three of the five patients studied developed CAS which was associated with acute elevation in coronary sinus TX B2; the two non-CAS patients with drug provocation had undetectable coronary sinus TX B2. We conclude that abnormal platelet activation takes place in the coronary circulation of CAD patients, and that production of acute myocardial ischemia by CAS occurs with increased coronary sinus TX B2.

Angina Pectoris↗
PubMed1980

Improved catheter for regional coronary sinus flow and metabolic studies.

An improved coronary sinus catheter has been developed whose enhanced flexibility facilitates catheterization of the great cardiac vein. It allows simultaneous thermodilution measurement of blood flow in the great cardiac vein and proximal coronary sinus, easy withdrawal of blood from both sites and bipolar atrial pacing from the proximal coronary sinus. The accuracy of flow measurement with this catheter has been validated by in vitro testing, and the catheter has been used successfully in eight patients. The advantages of this improved catheter over the existing coronary sinus thermodilution catheter are discussed.

Cardiac Catheterization↗
PubMed1980

Efficacy of diltiazem for control of symptoms of coronary arterial spasm.

To evaluate the efficacy of the calcium antagonist diltiazem for therapy of active coronary arterial spasm, 13 patients with clinical variant angina attributed to documented coronary arterial spasm completed a prospective randomized double-blind crossover trial of diltiazem (120 and 240 mg/day) versus placebo. Response was assessed with the diary technique measuring frequency of angina, consumption of nitroglycerin and percent of pain-free days. When 120 mg of diltiazem/day was compared with the paired placebo period there was a significant increase in percent of pain-free days (from 43 to 71 percent [p = 0.03]), but no significant decrease in frequency of angina (p = 0.06) or consumption of nitroglycerin (p = 0.32). When 240 mg of diltiazem/day was compared with the paired placebo period there was a significant increase in percent of pain-free days (from 50 to 79 percent [p = 0.03]) and a significant decrease in both frequency of angina (from 1.6 to 0.4 episodes/day [p = 0.03]) and consumption of nitroglycerin (from 1.3 to 0.4/day [p = 0.01]). Diltiazem was found to be a highly effective drug for control of symptoms of active coronary arterial spasm, without side effects and with excellent patient tolerance.

Aged↗
PubMedDate not supplied

Assessing new techniques in coronary angioplasty.

New devices for coronary intervention have been used in thousands of patients over the past several years. Although most such devices are still investigational, they hold promise in eliminating some of the hindrances to the broader, more successful use of conventional angioplasty. These new devices seem more effective than conventional angioplasty in treating eccentric or ulcerated lesions, ostial stenosis or stenosis of the LAD artery, disease in older saphenous vein grafts, restenotic lesions after prior intervention, and dissected vessels with actual or threatened abrupt closure. The difficulty facing each clinician is deciding which device to use under which circumstances in order to provide the safest, most durable, and most cost-effective treatment for the individual patient. Careful and critical analysis of the growing body of information regarding experience with these newer devices will be needed in order to accomplish this goal.

Angioplasty, Balloon, Coronary↗