Clopidogrel effects on thrombolysis effectiveness and clinical course of ST elevation myocardial infarction (30-day follow-up)

Abstract

Aim. To study clopidogrel effects on thrombolysis (TL) effectiveness and 30-day prognosis in patients with ST elevation myocardial infarction (STEMI).
Material and methods. The study included 111 patients with ECG-verified STEMI. Before hospital admission, all participants received loading aspirin dose (250 mg/d); 60 patients additionally received loading clopidogrel dose (300 mg/d): before admission (n=25) or at hospital, before TL (n=35). For the next 30 days, these patients received combined antiplatelet therapy (APLT): clopidogrel (75 mg/d) and aspirin (100 mg/d). Group 2 (n=51) included MI patients receiving aspirin only (loading dose followed by 100 mg/d dose). During 30-day follow-up, therapy effectiveness was assessed by cumulative incidence of cardiovascular events (CVE). Therapy safety was assessed by hemorrhage rates in two groups.
Results. ST normalization rates at 60, 90, and 180 minutes post-TL were similar in two groups. Further analysis demonstrated a tendency for better ST normalization in pre-hospital clopidogrel administration. Hemorrhage rates were similar in two groups. During the follow-up, 8 patients died (7,2%). All fatal cases were registered during hospitalization. Cumulative CVE incidence was significantly lower in combined APLT group: 6,7% vs 23,5% (р=0,01) and 21,7% vs 41,2% (р=0,02), respectively. This beneficial effect of combined APLT was registered as early as the first days of the follow-up.
Conclusion. Adding clopidogrel to standard treatment of STEMI patients who underwent TL is associated with significant improvement in 30-day clinical outcomes.