Prognostic significance of right ventricular ejection fraction for persistent complex ventricular arrhythmias and/or sudden cardiac death after first myocardial infarction: relation to infarct location, size and left ventricular function.

To assess the prognostic significance of right ventricular dysfunction after a first myocardial infarction for complex ventricular arrhythmias and or sudden cardiac death in relation to infarct location, size and left ventricular function, a series of 127 consecutive patients was prospectively studied and followed up for one year. Prior to hospital discharge, a 24-hour electrocardiographic recording and radionuclide angiocardiography were performed. Right ventricular ejection fraction was related to inferior infarct location and size (r = 0.45, P less than 0.01): similarly left ventricular ejection fraction was related to anterior infarct location and size (r = 0.76, P less than 0.001). The incidence of severe ventricular arrhythmias was significantly higher in patients with isolated right or left ventricular dysfunction compared to patients with normal function; it was highest in patients with severe depression of both ventricles. Patients with complex ventricular arrhythmia and/or sudden cardiac death had significantly reduced left and right ventricular ejection fractions. Detailed analysis in patients with left ventricular ejection fraction greater than 0.40 vs. less than or equal to 0.40 showed that presence of complex ventricular ectopic activity and/or sudden cardiac death after myocardial infarction was related not only to left, but also independently to right ventricular dysfunction. These results imply a significant prognostic contribution of right ventricular dysfunction to the occurrence of severe ventricular arrhythmias and/or sudden cardiac death after myocardial infarction independent of and additive to left ventricular dysfunction.