Primary percutaneous coronary intervention (PCI) has become an alternative to thrombolytic therapy as a reperfusion strategy for ST-elevation acute myocardial infarction (AMI).

The main goal of this study was to determine whether PCI and thrombolytic therapy achieve comparable reperfusion rates, as evidenced by ST-segment resolution. Secondary end points included infarct vessel patency rates before hospital discharge and short- and long-term outcomes. Patients with ischemic chest pain with duration ≤12 hours and no contraindication for thrombolytic therapy were included.

Between October 1993 and August 1995, 58 patients were randomly assigned to streptokinase (SK) and 54 patients to primary PCI. Baseline clinical characteristics and infarct location were well balanced in both groups. Median age (interquartile range) was 68 (58, 75) years, 29% were women, and 78% of the patients met at least one criterion for “not low risk” AMI (anterior location, age >70 years old, previous MI, systolic blood pressure <100 mm Hg, and/or heart rate >100 bpm). The median time from symptom onset to random assignment was 217 (139, 335) minutes in the PCI group and 210 (145, 334) minutes in the SK group. Median random assignment to balloon time was 82 (55, 100) minutes, and median random assignment to needle time was 15 (10, 26) minutes (P < .0001). TIMI grade 3 flow after primary PCI was obtained in 85% of patients. The proportion of patients with ST-segment resolution ≥50% at 120 minutes was 80% in the PCI group and 50% in the SK group (P = .001). The predischarge angiogram showed the presence of TIMI 3 flow in 96% of patients who received PCI and 65% of patients who received SK (P < .001). A composite of in-hospital death, reinfarction, severe heart failure, stroke, and major bleeding occurred in 15% of patients who received PCI and 21% of patients who received SK (P = .4). At 3 years, freedom from the composite end point of AMI, postdischarge revascularization, and death was 61% in the PCI group and 40% in the SK group (P = .025).

Our study shows that primary PCI, as compared with SK, is associated with more effective ST-segment resolution, higher patency rates in the infarct vessel at 7 days, and more favorable clinical outcomes at 3 years of follow-up.