EFFECTS OF THROMBOLYTIC THERAPY IN ACUTE INFERIOR MYOCARDIAL-INFARCTION WITH OR WITHOUT RIGHT-VENTRICULAR INVOLVEMENT

Objectives. This study assessed the prognostic impact of right ventric ular involvement (RVI) in streptokinase treated patients with inferior acute myocardial infarction (AMI) stratified for small or large AMI. Background. Only scant data exist from small studies about the impact of reperfusion therapy on survival in patients with RVI during inferio r AMI. Methods. Right ventricular involvement was assessed by ST-segme nt elevation greater than or equal to 0.1 mV in lead V4R and infarct s ize by the extent of ST-segment deviation on the baseline electrocardi ogram: small AMI = sum ST-segment elevation less than or equal to 0.8 mV and no precordial ST-segment depression (small ST); large AMI = pre sence of precordial ST-segment depression or sum ST-segment elevation >0.8 mV (large ST) in 522 inferior AMI patients of the Hirudin for Imp rovement of Thrombolysis (HIT-4) Trial. In 187 patients, 90-min corona ry angiography was performed. Results. Right ventricular involvement w as present in 169 patients (32%). Higher 30-day cardiac mortality rate s with RVI (5.9% vs. 2.5%) were related to larger infarct size rather than to RVI. For large ST, a proximal right coronary artery lesion was observed in 52% with and in 23% without RVI. Patency rates at 90 min were similar (54% vs. 52%). In the 28% of patients who had small ST, c ardiac mortality was less than 1% irrespective of the presence of RVI. Coronary artery lesions were mostly located distally. Patency rates m ere 27% with and 80% without RVI. Conclusions. ST-segment elevation of greater than or equal to 0.1 mV in V4R in inferior AMI patients is as sociated with larger infarct size and higher 30 day mortality rates. R ight ventricular involvement is not an independent predictor of surviv al. In patients with small ST, cardiac mortality is low even if ST V4R is greater than or equal to 0.1 mV. (C) 1998 by the American College of Cardiology.