Prognostic value of clinical markers of reperfusion in patients with acute myocardial infarction treated by thrombolytic therapy.

Patients who cannot be reperfused after thrombolytic therapy have a high mortality rate. Noninvasive clinical markers of reperfusion have been widely studied, yet their prognostic significance remains unclear. To assess the prognostic value of commonly used noninvasive clinical markers of early reperfusion we studied 327 patients who received intravenous thrombolytic treatment (1.5 MU streptokinase in 1 hour or 100 mg alteplase in 3 hours) within 6 hours of acute infarction. Successful clinical reperfusion (SCR) was defined as the presence of at least two of the following criteria at 2 hours after thrombolytic treatment: (1) significant relief of pain (a 5-point reduction on a 1 to 10 subjective scale), (2) > or =50% reduction of sum of ST segment elevation, and (3) abrupt initial increase of creatine kinase levels (more than twofold over the upper-normal or baseline elevated values). Clinical variables that were significantly associated by univariate analysis were tested by multivariate analysis to obtain independent predictors of 30-day mortality rate. SCR was present in 210 (64%) patients (group 1), and absent in 117 (36%) patients (group 2). The groups were similar for most baseline characteristics, although group 2 patients were slightly older (mean 60 vs 57 years, p < 0.02). Thirty-day outcomes for group 2 patients compared with group 1 patients were heart failure in 23.1% and 10.5% (p < 0.005), progression to cardiogenic shock in 12.8% and 0.5%, (p < 0.00001), and death in 16.2% and 3.8% (p < 0.0001), respectively. By multivariate analysis the Killip class at admission (p < 0.00001), the absence of SCR (p = 0.017), anterior infarct location (p = 0.021), and age (p = 0.03) were independent predictors of mortality rate, and sex (p = 0.051) had borderline significance. The absence of SCR defined a group of patients with significantly higher mortality rate (odds ratio 4.89, 95% confidence interval 2.07 to 11.57). Three simple noninvasive clinical criteria of successful reperfusion may be used to identify a group of patients with poor prognosis after thrombolytic therapy in whom alternative strategies could be applied.

Frequency, significance, and cost of recurrent ischemia after thrombolytic therapy for acute myocardial infarction. TAMI Study Group.

Early postinfarction angina implies an unfavorable prognosis. Most published information on this outcome represents data collected in the prethrombolytic era, in which definitions and populations differed considerably. Our purpose was to evaluate the incidence and importance of recurrent ischemia after administration of thrombolytic therapy. We studied patients enrolled in the Thrombolysis and Angioplasty in Myocardial Infarction studies. Patients were enrolled into 5 studies with similar entry criteria; 552 patients were treated with tissue plasminogen activator (t-PA), 293 were treated with urokinase, and 385 received both thrombolytic agents. Recurrent ischemia was defined as symptoms in association with electrocardiographic changes; reinfarction was defined as a reelevation of creatine kinase myocardial band isoenzyme in an appropriate clinical setting. Both recurrent ischemia and reinfarction occurred in 42 patients (3.4%), recurrent ischemia alone occurred in 226 (18%), whereas neither occurred in 964 (78%). Although baseline characteristics were similar among the 3 groups, in-hospital cardiac events (total 73 deaths, 253 heart failure episodes) were not: in-hospital mortality in patients with reinfarction was 21%; with recurrent ischemia, 11%; and with neither event, 4% (p < 0.0001). The in-hospital heart failure rate of patients with reinfarction was 50%; with recurrent ischemia alone, 31%; and with neither event, 17% (p < 0.0001). As expected, median in-hospital costs were highest in patients with reinfarction ($26,802), intermediate for those with recurrent ischemia alone ($18,422), and lowest in patients with neither event ($15,623). Recurrent myocardial ischemia after thrombolytic therapy is a frequent, important, and expensive adverse clinical outcome, making it a critical target for therapeutic intervention.