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J L Halperin

Publications and source records attributed to J L Halperin.

At least 37 records · Page 2Linked to original sources
PubMed1999

Aortic plaque in atrial fibrillation: prevalence, predictors, and thromboembolic implications.

BACKGROUND AND PURPOSE: Thoracic aortic plaque identified by transesophageal echocardiography heightens the risk of stroke associated with atrial fibrillation (AF). We sought to identify the prevalence, predictors, and implications of aortic plaque in patients with nonvalvular AF. METHODS: Thoracic aortic plaque was prospectively sought in 770 persons with AF with the use of transesophageal echocardiography and classified as simple or complex on the basis of thickness >/=4 mm, ulceration, or mobility. Clinical and echocardiographic features of thromboembolism were correlated by multivariate analysis. RESULTS: Aortic plaque was detected in 57% of the cohort, and complex plaque was detected in 25%. Both were found more frequently in the descending than in the proximal aorta. Potentially etiologic patient characteristics independently associated with complex plaque included advanced age, history of hypertension, diabetes, and past or present tobacco use. Comorbidities associated with aortic plaque were prior thromboembolism, increased pulse pressure, ischemic heart disease, stenosis or sclerosis of the aortic valve, mitral annular calcification (>10%), elevated serum creatinine concentration, spontaneous echo contrast in the left atrium or appendage, and left atrial appendage thrombus. The prevalence of complex plaque in patients aged <70 years with <10% mitral annular calcification, without ischemic heart disease, or without pulse pressure >/=65 mm Hg was 4% (95% CI, 1% to 6%). CONCLUSIONS: Aortic plaque is prevalent in patients with AF and is associated with atherosclerosis risk factors and with left atrial stasis or thrombosis, which are themselves independent stroke risk factors. Since the predominant location of complex plaque was in the descending aorta, the role of aortic plaque as a source of embolism in AF is uncertain.

Aged↗
PubMed1998

Transesophageal echocardiographic correlates of clinical risk of thromboembolism in nonvalvular atrial fibrillation. Stroke Prevention in Atrial Fibrillation III Investigators.

OBJECTIVES: This study explored the mechanisms linking clinical and precordial echocardiographic predictors to thromboembolism in atrial fibrillation (AF) by assessing transesophageal echocardiographic (TEE) correlations. BACKGROUND: Clinical predictors of thromboembolism in patients with nonvalvular AF have been identified, but their mechanistic links remain unclear. TEE provides imaging of the left atrium, its appendage and the proximal thoracic aorta, potentially clarifying stroke mechanisms in patients with AF. METHODS: Cross-sectional analysis of TEE features correlated with low, moderate and high thromboembolic risk during aspirin therapy among 786 participants undergoing TEE on entry into the Stroke Prevention in Atrial Fibrillation III trial. RESULTS: TEE features independently associated with increased thromboembolic risk were appendage thrombi (relative risk [RR] 2.5, p = 0.04), dense spontaneous echo contrast (RR 3.7, p < 0.001), left atrial appendage peak flow velocities < or = 20 cm/s (RR 1.7, p = 0.008) and complex aortic plaque (RR 2.1, p < 0.001). Patients with AF with a history of hypertension (conferring moderate risk) more frequently had atrial appendage thrombi (RR 2.6, p < 0.001) and reduced flow velocity (RR 1.8, p = 0.003) than low risk patients. Among low risk patients, those with intermittent AF had similar TEE features to those with constant AF. CONCLUSIONS: TEE findings indicative of atrial stasis or thrombosis and of aortic atheroma were independently associated with high thromboembolic risk in patients with AF. The increased stroke risk associated with a history of hypertension in AF appears to be mediated primarily through left atrial stasis and thrombi. The presence of complex aortic plaque distinguished patients with AF at high risk from those at moderate risk of thromboembolism.

Aged↗
PubMed1995

Clinical and echocardiographic features of intermittent atrial fibrillation that predict recurrent atrial fibrillation. Stroke Prevention in Atrial Fibrillation (SPAF) Investigators.

In addition to antithrombotic therapy, 2 treatment strategies for intermittent atrial fibrillation (AF) are evolving: suppression of AF or control of the ventricular response during AF. Clinical and echocardiographic features that predict recurrent AF may influence the choice of management. In this study, clinical, echocardiographic, and electrocardiographic data from 486 patients with intermittent AF enrolled in the Stroke Prevention in Atrial Fibrillation studies were analyzed. Patients with intermittent AF were younger (p < 0.001), had fewer incidences of systemic hypertension (p < 0.007) and heart failure (p < 0.001), and had more recent-onset AF than patients with constant AF. They also had a smaller mean left atrial diameter, a lower prevalence of a large (> 5 cm) left atrium, better left ventricular performance by echo, and less mitral regurgitation. After a mean follow-up of 26 months, 51% of patients remained in sinus rhythm and 49% of patients developed recurrent AF, including 12% who had AF, as seen on all follow-up electrocardiograms. Clinical factors predicting recurrent AF were age, heart failure, and myocardial infarction. An enlarged left atrium was associated with recurrent intermittent AF; an enlarged left ventricle predicted conversion to constant AF. Thus, clinical and echocardiographic parameters predict recurrent AF in patients with intermittent nonvalvular AF.

Age Factors↗
PubMed1994

Aortic dissection: a medical perspective.

Over the past 3 years, a greater understanding of predisposing factors and the pathology of the aortic wall has yielded more insights into the pathogenesis, as well as into more accurate diagnostic and preventive methods. This update will discuss: (1) the incidence, definition, and recent classification of aortic dissection; (2) epidemiology, medical, and recent surgical series; (3) the pathogenesis and risk factors; (4) clinical features and evolving noninvasive imaging approaches to diagnosis; and (5) management from a medical perspective.

Aortic Dissection↗
PubMed1993

Stroke prevention in atrial fibrillation.

Atrial fibrillation (AF) is a risk factor for ischemic stroke. In randomized trials, AF raised the risk of stroke nearly sixfold, cumulating in a 35% risk over a lifetime. Anticoagulation with warfarin reduces the danger of ischemic stroke, but carries hemorrhagic risks, making this agent unsuitable for treating many patients. Platelet inhibitor therapy with aspirin was highly effective for patients younger than 75 years of age in one study, but the reason for lower efficacy in older individuals is perplexing. These trials support a thrombotic mechanism for most strokes in patients with AF, but leave physicians in a quandary as to selection of optimum prophylaxis. Secondary analysis of patients given placebo identified predictors of thromboembolism, including a history of hypertension, congestive heart failure, and prior stroke or transient ischemic attack, and echocardiographic findings of left ventricular dysfunction or left atrial enlargement. The absence of these risk factors selects a fairly large subgroup of AF patients at comparatively low risk of stroke, for whom the danger and inconvenience of chronic anticoagulation may not be warranted. It is becoming clear that specific clinical and echocardiographic features allow individualized antithrombotic approaches within the broad category of patients with AF, to enhance therapeutic benefit while minimizing hemorrhagic risk.

Anticoagulants↗
PubMed1992

Antiarrhythmic drug therapy and cardiac mortality in atrial fibrillation. The Stroke Prevention in Atrial Fibrillation Investigators.

BACKGROUND AND OBJECTIVES: The relation between cardiac mortality and antiarrhythmic drug administration has not been fully determined. This relation was analyzed in 1,330 patients enrolled in the Stroke Prevention in Atrial Fibrillation Study, a randomized clinical trial comparing warfarin, aspirin and placebo for the prevention of ischemic stroke or systemic embolism in patients with nonvalvular atrial fibrillation. METHODS: Patients who received antiarrhythmic drug therapy for atrial fibrillation in this study were compared with patients not receiving antiarrhythmic agents. The relative risk of cardiac mortality, including arrhythmic death, in patients receiving antiarrhythmic drug therapy was determined and adjusted for other cardiac risk factors. RESULTS: In patients receiving antiarrhythmic drug therapy, cardiac mortality was increased 2.5-fold (p = 0.006, 95% confidence interval [CI] 1.3 to 4.9) and arrhythmic death was increased 2.6-fold (p = 0.02, 95% CI 1.2 to 5.6). Among patients with a history of congestive heart failure, those given antiarrhythmic medications had a relative risk of cardiac death of 4.7 (p less than 0.001, 95% CI 1.9 to 11.6) compared with that of patients not so treated; the relative risk of arrhythmic death in the treated group was 3.7 (p = 0.01, 95% CI 1.3 to 10.4). Patients without a history of congestive heart failure had no increased risk of cardiac mortality (relative risk 0.70, 95% CI 0.2 to 3.1) during antiarrhythmic drug therapy. After exclusion of 23 patients with documented ventricular arrhythmias and adjustment for other variables predictive of cardiac death, patients receiving antiarrhythmic drugs were not at increased risk of cardiac death or arrhythmic death. However, in patients with a history of heart failure who received antiarrhythmic drug therapy, the relative risk of cardiac death was 3.3 (p = 0.05, 95% CI 0.99 to 11.1) and that of arrhythmic death was 5.8 (p = 0.009, 95% CI 1.5 to 21.7) compared with the risk in patients not taking antiarrhythmic medications. CONCLUSIONS: Although antiarrhythmic drug therapy was not randomly determined in this trial, the data suggest that in patients with atrial fibrillation and a history of congestive heart failure, the risk of such therapy may outweigh the potential benefit of maintaining sinus rhythm.

Anti-Arrhythmia Agents↗
PubMed1992

Dextrocardia.

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Adult↗
PubMed1990

Antithrombotic therapy in cardiac disease: an approach based on pathogenesis and risk stratification.

An approach to the management of thrombosis and embolism in various cardiovascular disorders is discussed. This approach is based on current knowledge of pathogenesis and risk of thromboembolism. Rational therapeutic guidelines are formulated along the lines of anatomic location (arterial circulation, cardiac chambers or prosthetic valves), pathophysiology (activation of platelets or the coagulation system, or both), and degree of thromboembolic risk. With clear understanding of these factors, it may be possible to determine the most suitable platelet inhibitor or anticoagulant regimen for the individual patient, and whether these agents should be given singly or in combination.

Anticoagulants↗