EMERGING OPTIONS IN THE MANAGEMENT OF MYOCARDIAL-ISCHEMIA

Improved understanding of the pathogenesis of symptomatic and silent m yocardial ischemia has led to important advances in the prevention and treatment of these syndromes. For example, recognition of the role of platelets in the atherogenic process and of thrombosis in acute myoca rdial ischemia has led to extensive use of aspirin and thrombolytic th erapy, with resultant decreases in mortality. Both nitrates and beta-a drenergic blockers effectively alleviate myocardial ischemia. However, long-term nitrate use is limited by the occurrence of tolerance. beta blockers have been shown to decrease subsequent cardiovascular events in patients with acute myocardial infarction; however, adverse effect s are often associated with their use. Calcium antagonists have been s hown to be effective in the treatment of stable and vasospastic angina . In patients with coronary artery disease sad symptoms resulting from either fixed obstruction or vasospasm, these agents decrease the freq uency of angina episodes. The 3 types of calcium antagonists currently available-phenylalkylamine, benzothiazepine, and dihydropyridine deri vatives-while chemically a heterogeneous group, share the common prope rty of decreasing depolarization of smooth muscle, albeit to varying d egrees. Nonetheless, other characteristics, including varying electrop hysiologic effects, distinguish these groups. The novel calcium antago nist amlodipine is effective and well tolerated as an antianginal agen t, and offers the advantage of once-daily dosing. Calcium antagonists appear to be well tolerated in patients with concomitant conditions su ch as diabetes and are effective in commonly coexistent cardiovascular disorders such as hypertension.