Invasive versus conservative strategies in unstable angina and non-Q-wave myocardial infarction following treatment with tirofiban:: Rationale and study design of the international TACTICS-TIMI 18 trial

In the management of unstable angina and non-Q-wave acute myocardial infarction (AMI), there is considerable debate regarding the use of invasive strategy versus conservative strategy. The Thrombolysis In Myocardial Infarction (TIMI) III B trial found similar clinical outcomes for the 2 strategies, but the Veterans Administration Non-Q-Wave Infarction Strategies in-Hospital trial found a higher mortality with the invasive strategy. Both these trials were conducted before platelet glycoprotein IIb/IIIa inhibition and coronary stenting, bath of which improve clinical outcome. Thus, there is a need to reexamine the question of which management strategy is optimal in the current era of platelet glycoprotein IIb/IIIa inhibition and new coronary interventions. The Treat Angina with Aggrastat and determine Cost of Therapy with an Invasive or Conservative Strategy (TACTICS-TIMI 18) trial is an international, multicenter, randomized trial that is evaluating the clinical efficacy of early invasive and early conservative treatment strategies in patients with unstable angina or non-Q-wave AMI treated with tirofiban, heparin, and aspirin. Patients are randomized to an invasive strategy, involving cardiac catheterization within 4 to 48 hours and revascularization with angioplasty or bypass surgery if feasible, versus a conservative strategy, where patients are referred for catheterization only for recurrent pain at rest or provokable ischemia. The primary end point is death, MI, or rehospitalization for acute coronary syndromes through a 6-month follow-up. The trial is also testing the "troponin hypothesis," that baseline troponins T and I will be useful in selecting an optimal management strategy. (C) 1998 by Excerpta Medica, Inc.