[Incidence and extent of right ventricular functional disorders following the 1st myocardial infarction]

A series of 63 patients were studied by gated radionuclide angiocardiography 51/2 weeks after their first acute myocardial infarction. Left (LVEF) and right (RVEF) ventricular ejection fraction were assessed in three groups of patients: 12 patients with transmural anterior infarctions, 35 patients with transmural inferior infarctions and 16 patients with non-transmural infarctions. LVEF was depressed only in the group of patients with anterior infarctions (34.4 +/- 16.3%) but remained within normal limits in the other two groups. RVEF was reduced in 64% of patients with inferior infarctions; the mean value in this group was 36.3 +/- 10.2% (normal range 48 +/- 8%, p less than 0.02). In the other two groups RVEF was only rarely reduced and the mean values were within normal limits. Regional wall motion abnormalities ( WMA ) were found in 47% of all patients, those localised in the left ventricle matching ECG localisation of necrosis in 86% of cases. Only patients with infarctions of the inferior left ventricular wall were found to have WMA in the right ventricle. Functional signs of ischemia (decrease of RVEF or LVEF during physical exercise) were found in 34% of patients with transmural infarctions and 57% of patients with non-transmural infarctions. Radionuclide angiocardiography showed itself a valuable method for assessing persistent dysfunction after acute myocardial infarction not only of the left but also of the right ventricle, a phenomenon not easily detected clinically.