Racial differences in performance of invasive cardiac procedures in a Department of Veterans Affairs Medical Center.

Racial differences have recently been described in hospital practice, most notably with regard to cardiac procedure utilization. To evaluate the possible reasons behind these differences, we analyzed statistics generated from a surgical referral conference at a large, tertiary care Veterans Affairs hospital between the years 1988 and 1996. In this setting, there is no financial incentive for physicians to recommend or perform invasive procedures, as all physicians are salaried employees of the Veterans Administration. Furthermore, all patients presented at conference have already had cardiac catheterization and are felt to be potential candidates for surgery or angioplasty. Cardiac therapeutic procedures (surgery or percutaneous transluminal coronary angioplasty) were recommended for 1075 of 1474 (72.9%) Caucasian patients and 207 of 322 (64.3%) African-American patients (odds ratio 1.497, 95% confidence interval 1.160 to 1.932, p = 0.0022). Of those patients presented with the option of an invasive procedure, 32 of 207 (15.4%) African-American patients and 89 of 1075 (8.3%) Caucasian patients refused any invasive procedure (odds ratio 2.026, 95% confidence interval 1.311 to 3.130, p = 0.0025). We conclude that reluctance by African-American patients to undergo invasive cardiac procedures may help explain observed disparities in race-related cardiac care.

Prognostic significance of spontaneous echo contrast in the thoracic aorta: relation with accelerated clinical progression of coronary artery disease.

OBJECTIVES: The purposes of this study were to identify the incidence of aortic smoke in an unselected cohort of patients and to determine the utility of this measurement as a clinical marker for future coronary events and long-term cardiac prognosis. BACKGROUND: Although spontaneous echo contrast detected within the cardiac chambers has been associated with an increased risk of thromboembolism, less is known about "smoke" within the thoracic aorta and its relation to progression of coronary artery disease. METHODS: We prospectively assessed 118 unselected, consecutive male patients (mean age 67 years, range 29 to 86) who underwent transesophageal echocardiography (TEE). The presence of aortic smoke was identified by swirling echodense shadows distinct from high gain artifact. A positive result required confirmation by two of three independent observers. RESULTS: Aortic smoke without dissection was found in 25 of the patients (21%). Indications for TEE, coronary risk factors, the incidence of reduced left ventricular ejection fraction and mitral insufficiency and known coronary artery disease severity collectively did not differ significantly at baseline between the groups with and without smoke. Follow-up averaged 20.4 months (range 18 to 24) and was 100% complete for mortality and 98% complete for morbidity. The presence of aortic smoke was an independent predictor of myocardial infarction (16.0% vs. 2.2%, p < 0.005) and cardiac death (20.0% vs. 1.1%, p < 0.0001). These statistics remained significant after covarying for age, ejection fraction < 50%, hypertension, diabetes, aortic dimension, the presence of an atheromatous plaque and smoke in the left atrium. CONCLUSIONS: Spontaneous echo contrast detected within the thoracic aorta by transesophageal echocardiography is a common and important clinical marker that is strongly associated with an increased risk for future myocardial infarction and cardiac mortality. Future studies will attempt to define the pathophysiology of this relation and assess whether aggressive revascularization strategies and antithrombotic therapy may aid in the reduction of this risk.

Long-term prognostic significance of dobutamine echocardiography in patients with suspected coronary artery disease: results of a 5-year follow-up study.

OBJECTIVES: This study sought to assess the long-term prognostic utility of dobutamine stress echocardiography in predicting fatal and nonfatal cardiac events. BACKGROUND: Although dobutamine stress echocardiography has improved sensitivity and specificity for detection of coronary artery disease, little is known of its predictive value for long-term cardiac events. Therefore, we followed up 120 consecutive patients who underwent dobutamine echocardiography for suspected coronary disease from March 1989 to August 1991. METHODS: All patients presenting for coronary angiography for chest pain were eligible for recruitment. Follow-up was 100% complete at 5 years (range 3.0 to 6.1). Cardiac events were defined as cardiac death or nonfatal myocardial infarction or the need for coronary revascularization (coronary angioplasty or bypass surgery). RESULTS: Positive (n = 78) and negative (n = 42) dobutamine test groups differed in their rates of coronary artery bypass graft surgery (37.2% vs. 9.5%, p < 0.001, respectively) and mortality. Of 26 total deaths, 22 occurred in the group with positive dobutamine test results (28% vs. 9.5%, p < 0.018); all 7 cardiac deaths occurred in this group as well (9% vs. 0%, p < 0.045). By multivariate regression analysis, positive results on dobutamine echocardiography remained independently predictive of future cardiac death after left ventricular ejection fraction and other clinical variables were accounted for. CONCLUSIONS: A positive finding on dobutamine echocardiography is an independent predictor of long-term cardiac mortality, whereas a negative finding confers a significantly reduced likelihood of cardiac death as much as 5 years from initial testing. We conclude that dobutamine stress echocardiography can be used to predict which patients with suspected coronary artery disease are at low risk for cardiac death and do not require concurrent nuclear or invasive testing.

Dobutamine stress testing in the cardiac catheterization laboratory.

Dobutamine stress ventriculography is a safe test that appears to separate groups of patients with and without significant coronary artery stenoses. In this study, all 7 patients with significant coronary artery stenoses who reached a heart rate > or = 110 beats/min had a positive stress test, whereas 9 of 10 control patients had a negative stress test.

Prognostic significance from 10-year follow-up of a qualitatively normal planar exercise thallium test in suspected coronary artery disease.

A normal exercise thallium-201 scintigram has been shown to confer an excellent prognosis over a 1- to 4-year follow-up period. However, progression of coronary disease could result in cardiovascular mortality with increasing time. Therefore, the vital status of 309 patients with normal stress thallium myocardial imaging was determined after an average of 10.3 years. Deaths were classified as cardiac or noncardiac. Statistical analysis was performed using Kaplan-Meier survival curves. Standardized mortality ratios were calculated and compared with those of an age- and sex-matched general population. Follow-up was complete in 288 patients (93%). Of 18 deaths, only 3 were cardiac; the remaining 15 were mainly secondary to cancer. Thus, cardiac mortality was 1% and total mortality 6.3% at 10 years. In addition, both all-cause and cardiac mortality rates were significantly less than would be expected in an age- and sex-adjusted segment of the general population. Thus, normal exercise thallium scintigraphy retains its high negative predictive value for death < or = 10 years after initial testing. This supports the use of stress thallium imaging to predict which patients with suspected coronary artery disease are at low risk for cardiac death and thus do not need invasive testing.