Heart Disease - Treatment

The development of pharmacological agents that stimulate regression of LVH, modulate insulin sensitivity, alter lipid metabolism, and control vascular tone provide new avenues for research on the treatment of CHD in blacks. Thrombolysis and coronary revascularization procedures, such as coronary artery bypass grafting (CABG) and percutaneous transluminal coronary angioplasty (PTCA), have been significant therapeutic innovations. Studies of CABG surgery indicate better survival rates, but less favorable functional outcomes, for blacks treated surgically than for those treated medically. Relatively little is known about the use of PTCA in blacks. Limited studies of thrombolytic therapy in blacks show higher patency rates for infarctrelated arteries compared with whites and a higher risk of bleeding complications, although survival to hospital discharge and other clinical outcomes are similar. There are minimal data on the value of coronary atherectomy in blacks.

Whereas reduction in the development of stroke attributable to control of hypertension has exceeded that predicted from epidemiological studies, reduction in CHD related to antihypertensive treatment has been much less striking. Given that hypertension is more common in blacks than in whites, studies should be conducted to define the possible contribution of antihypertensive therapy to mortality from CHD in blacks. Outofhospital CHD deaths also are more common in blacks. Methodologies for identifying individuals at risk of acute coronary events, especially sudden death, should be evaluated further. Identification and evaluation of antiarrhythmic agents designed to reduce the risk of lifethreatening arrhythmias have been difficult in the past; however, development of effective therapies for patients at high risk (e.g., blacks and other patients with documented CHD, hypertension, LVH, normal coronary arteries with poor coronary reserve) should continue to be a goal of research.

Use of pharmacological therapy for ischemic heart disease has been influenced by recent major advances in coronary revascularization and thrombolysis. However, innovative research on the pathogenesis of atherosclerosis and greater understanding of the role of the endothelium, vascular smooth muscle, and vascular reactivity have led to renewed enthusiasm for established, as well as newer, therapeutic agents.

Clinical trials are needed, particularly related to CHD in blacks. These should address the efficacy of pharmacological agents (e.g., antioxidants, antiinflammatory substances, growth factor inhibitors) in modifying vascular and ventricular remodeling processes, as well as the impact of pharmaceuticals (e.g., angiotensinconverting enzyme inhibitors, calciumchannel blockers, estrogens) on the course of atherosclerotic and nonatherosclerotic CHD.

The prevalence of heart failure related to CHD is increasing as more patients survive acute coronary syndromes. Heart failure due to CHD or ischemic cardiomyopathy is now one of the most common diagnoses prompting hospital admission. Heart failure is more prevalent in blacks, perhaps because of coincident hypertension or diabetes mellitus. Research comparing ventricular dysfunction due to macrovascular versus microvascular disease and atherosclerotic versus nonatherosclerotic disease is needed, especially in blacks.

Ischemic cardiomyopathy is one of the major contributors to heart failure leading to cardiac transplantation. Studies are needed to determine more effective drug therapy for both systolic and diastolic dysfunction. The appropriateness and value of CABG surgery, PTCA, and thrombolysis, compared with conventional medical therapy, also need to be assessed. For this effort, existing data from multicenter interventional trials should be pooled as appropriate, and prospective clinical trials of various revascularization approaches should be conducted in blacks and compared with existing data in whites.