CLINICAL-TRIALS IN THROMBOLYTIC THERAPY .1. OUTCOME MARKERS THAT GO BEYOND MORTALITY REDUCTION

The use of outcome markers other than mortality reduction alone for ev aluating thrombolytic agents in patients with acute myocardial infarct ion (AMI) is discussed. Mortality has been a primary endpoint in clini cal trials evaluating thrombolytic agents for treatment of AMI. Howeve r, differences in mortality rates among thrombolytics are 1% or less a nd require tens of thousands of patients to detect. Broadening the end points studied of reperfusion, such as early resolution of ST segment elevation; and resolution of chest pain. Available longterm data show that the mortality benefit from alteplase is sustained over time and i s correlated with enzymatically determined infarct size, left ventricu lar function, the number of diseased vessels, and Thrombolysis in Myoc ardial Infarction flow grade at the time of discharge from the hospita l. Clinicians must also consider risk factors for stroke. Outcome meas ures other than mortality alone may help in determining which thrombol ytic agent is most effective clinically and in financial decision-maki ng without requiring large, expensive trials.