[Mid-term outcome of acute right ventricular dysfunction in biventricular myocardial infarction. Hemodynamic and...

This study was designed to evaluate the mid-term outcome of the right ventricular (RV) dysfunction which characterizes infarction of both ventricles in the acute phase. Thirteen patients hospitalized for inaugural posterior or infero-posterior infarction extending to the right ventricle (haemodynamic and cineangiographic diagnosis) were explored in the acute phase and 4 months later by right heart catheterization and selective cineangiography of the right ventricle in a 30 degrees RAO projection. The results were compared with those obtained in a control group. Haemodynamically, the RV filling pressures (p less than 0.001) and the indices of RV dysfunction--i.e. RV end-diastolic pressure/RV systolic pressure ratio (p less than 0.001) and right atrial pressure/pulmonary wedge pressure ratio (p less than 0.02)--were significantly decreased between the acute and chronic phases, but they remained pathological compared with those measured in the control group. Angiographically, the right ventricular dysfunction in the acute phase was reflected in an increase of the RV end-systolic volume (p less than 0.02) and a decrease of the RV ejection fraction (p less than 0.01), whereas diastolic cavitary dilatation was inconstant, with mean values of RV end-diastolic volume close to those found in the control group. The systolic dysfunction persisted, unchanged, during the chronic phase. Segmental kinetics of the inferior wall was much reduced in the acute phase (p less than 0.001), this hypokinesia partially regressing in the chronic phase; but in fact there were wide individual variations, and some patients even recovered an almost normal contractility. Tricuspid valve regurgitation was frequent (6/13 cases) in the acute phase and regressed in 2 out of 3 cases in the chronic phase; its presence introduced a degree of bias in the measurement of RV end-systolic volume and RV ejection fraction, with a tendency to underestimate the severity of diastolic dysfunction. To summarize, right ventricular dysfunction was constant but often modest in the acute phase and remained relatively stable at mid-term, whereas segmental kinetics of the inferior wall improved, sometimes dramatically.