[Right ventricular function in patients with chronic right ventricular infarction].

To assess right ventricular function in patients with chronic right ventricular infarction, Tc-99m angiocardiography was performed in 64 patients one to three months after the onset of myocardial infarction. These patients were categorized into four groups according to their hemodynamic data in the acute stage using the Forrester classification: 39 patients in group I, 15 in group II, eight in group III and two in group IV. Mean right atrial pressure was nearly equal to or greater than diastolic pulmonary arterial pressure in all patients in group III. We calculated right ventricular ejection fraction (RVEF) and the right ventricular end-diastolic volume index (RVEDVI) as the parameter of right ventricular function, and assessed right ventricular wall motion using the right ventricular regional ejection fraction images (RVREFI). 1. RVEF in group III (25 +/- 3%) was significantly lower than those in groups I, II and IV (44 +/- 6%, 45 +/- 7% and 37 +/- 4%, respectively), and RVEF of all patients in group III was less than 30%. 2. RVEDVI in group III (150 +/- 25 ml/m2) was significantly greater than those in groups I, II and IV (74 +/- 20 ml/m2, 59 +/- 14 ml/m2 and 91 +/- 36 ml/m2, respectively). 3. RVREFI in group III decreased at the inferior and/or septal regions of the right ventricle, indicating wall motion abnormalities at the corresponding sites. 4. Six patients in group III were examined by coronary angiography and all had definite lesions in the proximal portion of the right coronary artery.(ABSTRACT TRUNCATED AT 250 WORDS)