Prognostic Significance of Right Ventricular Involvement in Patients with Acute Inferior Myocardial Infarction

Acute inferior myocardial infarction (AIMI) frequently involves the right ventricle. Postmortem studies revealed that there is right ventricular involvement in 19 to 51 percent of patients with AIMI. Right ventricular infarction (RVI) increases the incidence of atrioventricular (AV) block, arrhythmias and heart failure in patients with AIMI; but there is no consistent information on in-hospital mortality rate. We hypothesized that RVI, as diagnosed by ST-segment elevation in the right precordial leads V3R and V4R, may affect the in-hospital prognosis of patients with AIMI. Data of 258 consecutive patients with AIMI who were admitted to the coronary care unit during January 1991 and March 1995 were analysed. 53 patients (Group 1) had signs of RVI, whereas 205 patients (Group II) had isolated AIMI. These groups were similar regarding sex, age, coronary risk factors and thrombolytic therapy. We found that Group I had significantly higher serious ventricular premature beats (Lown III or above) (55% vs 25%) (p=0.00002), VT-VF (15% vs 7%) (p<0.05), secondegree AV block (15% vs 6%) (p=0.04). third-degree AV block (25% vs 7%) (p<0.001), total AV block (57% vs 21%) (p<0.001), Killip II heart failure (23% vs 10%) (p=0.016) and QRS score (4.32±1.48 vs 3.95±1.31) (p=0.04) than patients without RVI (Group II). Group I had a in-hospital mortality rate similar to that found Group II (4% vs 8%) (p=NS). These data suggest that infarction extension from inferior wall to the right ventricle is related to an increase in the early complications of AMI but does not change the in-hospital mortality rate.