Prediction of coronary artery reperfusion after tissue plasminogen activator infusion

We investigated whether clinical and laboratory variables can predict perfusion status after t-PA administration, by using the data from 138 patients who received t-PA during the Thrombolysis in Myocardial Infarction (TIMI) I study. All clinical and laboratory variables that were collected at baseline or during perfusion for TIMI I were evaluated by the current study. Via stepwise discriminant analysis, 7 variables were closely associated with perfusion status at 90 minutes (listed in the order of their discriminant effect): baseline grade of stenosis in the infarct-related coronary artery, whether nausea was present during the infusion, baseline aspartate aminotransferase (SGOT) concentration, whether arrhythmias were present during the infusion, baseline fibrinogen concentration, baseline partial thromboplastin time, and baseline diastolic blood pressure. Baseline severity of stenosis and the likelihood of there being reperfusion were inversely related. Eighty-four percent of patients with adequate perfusion after 90 minutes of t-PA infusion were classified correctly, but only 50% of those without perfusion at 90 minutes were classified correctly. In addition, since 70% of the TIMI I patients, on average, did achieve perfusion, the use of these 7 variables added little predictive information. Our findings suggest that 1) there is as yet no practical way to predict reperfusion after t-PA therapy and 2) the severity of coronary stenoses, if known ahead of time, should be considered when selecting patients for thrombolytic therapy.