Thrombin Generation and Activity During Coronary Angioplasty: Influence of Angiographic Lesion Morphology.

OBJECTIVE: To investigate the relationships between coronary atherosclerotic plaque injury, lesion morphology, and activation of the coagulation cascade. BACKGROUND: Balloon angioplasty of coronary lesions may result in intracoronary thrombin generation and activity. It is unknown whether the angiographic morphology of the lesion prior to intervention, an indicator of the presence of thrombus in the lesion, is a determinant of the degree of coagulation cascade activation.

Double-blind, placebo-controlled study of the effects of carvedilol in patients with moderate to severe heart failure. The PRECISE Trial. Prospective Randomized Evaluation of Carvedilol on Symptoms and Exercise.

Background: Carvedilol has improved the symptomatic status of patients with moderate to severe heart failure in single-center studies, but its clinical effects have not been evaluated in large, multicenter trials.

Methods And Results: We enrolled 278 patients with moderate to severe heart failure (6-minute walk distance, 150 to 450 m) and a left ventricular ejection fraction < or = 0.35 at 31 centers.

Dose-response of chronic beta-blocker treatment in heart failure from either idiopathic dilated or ischemic cardiomyopathy. Bucindolol Investigators.

Background: Small-scale clinical investigations have demonstrated that single doses of beta-blocking agents can improve left ventricular function in heart failure from idiopathic dilated cardiomyopathy (IDC). The purpose of this multicenter clinical trial was to determine the dose-effect characteristics of beta-blockade in a heart failure population that includes ischemic dilated cardiomyopathy (ISCD).

Methods And Results: Bucindolol is a nonselective beta-blocking agent with mild vasodilatory properties.

Neutrophil-endothelial cell interaction in critical illness.

Sepsis syndrome frequently results in endothelial injury in many organ systems. To evaluate neutrophil-pulmonary endothelial cell interaction in the sepsis syndrome, we studied 39 critically ill patients prospectively and 20 normal volunteers. Thirteen patients with sepsis (mean age, 71.

Histamine mediates myocardial damage by an H1 mechanism independent of coronary blood flow.

Administration of histamine to rabbits may result in myocardial damage similar to that produced by catecholamines and the anthracycline antibiotics. To explore the mechanisms involved in histamine-mediated myocardial damage, conscious New Zealand white rabbits were pretreated with H1 and H2 receptor blocking agents, alone and in combination, and then administered histamine. Coronary artery blood flow was measured with radiolabeled microspheres in rabbits that received histamine alone, and in those that received an H1 blocking agent and histamine.

Effects of intravenous metoprolol on global and regional left ventricular function after coronary arterial reperfusion in acute myocardial infarction.

Coronary reperfusion in myocardial infarction improves infarct zone motion, but its effect on the global ejection fraction has been less consistent. The directional movement of the ejection fraction is determined by the opposing influences of improved infarct zone motion and diminishing hyperkinesia in the noninfarct zone. Noninfarct zone hyperkinesia has been attributed to catecholamine stimulation, the Frank-Starling mechanism or intraventricular interactions that unload noninfarcted segments.

A new method for assessing right-sided heart pressures using encapsulated microbubbles--a preliminary report.

A new noncatheter method for measuring pressures of the right side of the heart uses specially manufactured microbubbles of carbon dioxide injected into the peripheral venous system. Sudden expansion of these bubbles in the cardiac chambers causes bubble oscillations at a frequency that is primarily a function of surrounding pressure. The oscillations are recordable by a microphone on the chest wall.

Beta-adrenergic function in heart muscle disease and heart failure.

Using data derived from clinical and experimental observations, we examine the role of the myocardial beta-adrenergic receptor system in pathophysiologic processes involved in heart muscle disease and heart failure. The available data suggest that the sympathetic nervous system exerts important influences on myocardial structure and function. As such the beta-adrenergic pathways represents an obvious locus for therapeutic intervention in evolving cardiomyopathic states.

Mediation of subacute anthracycline cardiotoxicity in rabbits by cardiac histamine release.

We tested the hypothesis that cardiac histamine release mediates subacute doxorubicin (DXR) cardiotoxicity in rabbits. New Zealand white rabbits given DXR 20 mg/kg i.v.

Rapid, semiautomated technique for estimating left ventricular volume.

A new system for rapidly quantitating left ventricular volume using two-dimensional echocardiography is tested. This system relies on a microprocessor built into a sector scanner that immediately calculates the length, area, and volume of the chamber being imaged using the mathematical model of an ellipsoid of revolution. The calculations are made after the observer superimposes a smooth calibrated ellipse outline on the endocardium imaged with the sector scanner.

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.

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.