Comparison of right ventricular systolic function in idiopathic dilated cardiomyopathy and healed anterior wall myocardial infarction associated with atherosclerotic coronary artery disease.

A case-controlled study assessed right ventricular (RV) systolic function in 10 patients with idiopathic dilated cardiomyopathy (IDC) and in 10 with healed anterior wall myocardial infarction associated with atherosclerotic coronary artery disease (CAD). Each patient was matched for sex, left ventricular ejection fraction +/- 5% and pulmonary artery mean pressure +/- 5 mm Hg. All patients had sinus rhythm and a left ventricular ejection fraction < 45%. A new, well-validated thermodilution technique was used to assess RV ejection fraction and volumes. RV ejection fraction was lower in the IDC than in the CAD group (25 +/- 14% vs 36 +/- 11%; p < 0.02). Linear correlations between RV parameters and pulmonary artery pressure were significantly present in both groups. However, the slopes of the equations were not statistically different. In comparison with healed anterior wall myocardial infarction with CAD and for similar levels of left ventricular dysfunction, RV systolic function appeared to be more altered in IDC.