Ischemic heart disease remains the leading cause of death among African Americans, and the "risk factors" for coronary disease (including obesity, hypertension, left ventricle hypertrophy, and use of cigarettes) are higher in blacks than in whites. However, early research indicated that the incidence rate of heart disease is lower in blacks than in whites. The limited data therefore suggest that blacks have higher case fatality rates than whites.

The role of invasive cardiovascular procedures, primarily percutaneous transluminal angioplasty (PCTA) and coronary artery bypass grafting (CABG), in reducing the mortality rate from ischemic heart disease has been considered in recent years. If these procedures do reduce mortality, it is "disturbing that published studies have consistently described significant racial disparities in their utilization."

The authors review ten studies that examined the use of cardiac procedures, including angioplasty/catheterization, PTCA and CABG. Two studies using data from the 1970's (Oberman and Cutter, 1984 and Maynard et al., 1986) found that blacks were less likely to be treated surgically than white patients. The Maynard et al. study further noted that surgery was recommended less frequently for and accepted less frequently by blacks than whites. Two studies showed that rates of angiography and CABG were lower for blacks compared with whites using the National Hospital Discharge Survey data from 1979 to mid-1980's (Gillum, 1987 and Ford et al., 1989), two studies showed racial patterns in procedure use using Medicare data (Goldberg et al., 1992 and Franks et al., 1993), and one showed similar patterns using data from the Thrombolysis and Angioplasty in Myocardial Infarction study (Sane et al., 1970). Wenneker and Epstein (1989) were the first to show that coronary angioplasty, as well as angiography and CABG, was used less frequently for blacks than for whites. Racial differences in some or all three of these procedures were found using data from Massachusetts (Wenneker and Epstein, 1989), metropolitan Seattle (Marynard et al., 1991), and New York state (Hannan et al., 1991). These studies demonstrated that, while some of the differences may be explained by adjusting for age, sex, socioeconomic status, the severity of disease, and co-morbid condition, large racial patterns still exist. In addition, there is a direct correlation between the cost of the procedures and the size of the disparity.

Although these data are convincing, there are limitations to the studies that have yet to be adequately addressed. The authors note that the role of socioeconomic status rather than race in the pattern of health care utilization has not been sufficiently tested. Additionally, few of the studies were able to measure contraindications to procedures or the role of co-morbidity.

Causal explanations for these findings were also reviewed. Reduced access and cost are the most straightforward causal explanations; however, there are indications to suggest that racial patterns in access to health services and insurance coverage do not completely explain the racial patterns in utilization of cardiac procedures. Racial differences in severity of disease or type of hospital used have also been offered as explanations, although the available data do not support them. Reduced geographic access to facilities could be another barrier that has not been adequately addressed. Additionally, explanations have been offered based on the theory that blacks and whites differ with regard to their beliefs about the medical care system, and these beliefs, as well as the associated care-seeking behaviors of blacks, are such that they are less likely to undergo invasive procedures. Finally, subtle or overt racism by the health care providers or the health care system may be operative and would explain the racial patterns observed. "Physicians who view the maintenance of 'human capital' as an important role of medicine may be less eager to expend resources on minorities. This are is very difficult to evaluate, however, because of the absence of data."

The authors also suggest remedies and areas for future research. For example, efforts should be made to dispel beliefs that might exist in the medical community that blacks are less susceptible to ischemic heart disease, aiming interventions at medical students in particular. A reformation of the current health care system to one that offers equal access to these procedures to all persons may also go a long way in narrowing the gap in use of coronary procedures. Increasing the number of black physicians trained to perform these procedures may help change blacks' potentially negative attitude and beliefs about the health care system and may also improve access to these procedures for blacks. With regard to research needs, several suggestions were made. First, systems to conduct ongoing monitoring of cardiac procedure use are needed. Additionally, the effect of lower utilization of cardiac procedures must be established, including both mortality and quality of life. Finally, research particularly aimed at identifying which of the causal hypotheses are operating is needed. The authors also note the need to expand racial disparity research to include other minority groups, such as Latino, Native American, and Asian populations.