CURRENT ISSUES IN REPERFUSION THERAPY

With the establishment of thrombosis as the cause of myocardial infarc tion, the pivotal role of thrombolytics and primary angioplasty has ev olved. Large randomized trials with innovative methodologies have exam ined the role of these reperfusion therapies in the management of acut e coronary syndromes. Intravenous thrombolytic therapy decreases morta lity in a broad group of patients with acute myocardial infarction, Th e GUSTO trial established intravenous tissue plasminogen activator (tP A) used in combination with intravenous heparin as the most effective thrombolytic therapy. Importantly, the time to achieve reperfusion is crucial to the mortality benefit observed, and rapid attainment of Thr ombolysis in Myocardial Infarction (TIMI) trial grade 3 flow is achiev ed in only approximately 55% of patients who receive thrombolytics. Re occlusion, cellular damage, and microvascular dysfunction may contribu te to less than optimal results. Percutaneous transluminal coronary an gioplasty (PTCA) may be the preferred method of acute reperfusion ther apy based on higher rates of TIMI grade 3 flow and lower rates of reoc clusion and recurrent myocardial infarction. However, marked variation exists in outcomes and utilization rates among individual institution s, and the benefits of PTCA have not been consistently maintained at 6 months. The use of stents and anticoagulants may improve results, and pre-PTCA strategies also ore under investigation. Limitations remain in the efficacy of current reperfusion therapies, supporting the searc h for improved thrombolytic agents, primary angioplasty, stents, and a ntithrombotics with the goal of improving TIMI 3 flow rates and achiev ing reperfusion more rapidly. (C) 1998 by Excerpta Medica, Inc.