ABSTRACT
Right ventricular systolic and diastolic function was studied in patients with ischemic heart disease using equilibrium radionuclide ventriculography. In patients with inferior myocardial infarction and proximal right coronary lesions, the right ventricular ejection fraction (0.43 +/- 0.06, n = 10, mean +/- SD) and peak filling rate (1.7 +/- 0.4 EDV/sec) were lower than normals (0.57 +/- 0.07 and 2.7 +/- 0.4 EDV/sec, n = 10, p less than 0.001, respectively). In these patients, the right ventricular time to peak filling rate was longer than in normals (225 +/- 36 msec vs 136 +/- 45 msec, p less than 0.001), while the left ventricular ejection fraction remained normal. In patients with inferior myocardial infarction and distal right coronary lesions, the right ventricular ejection fraction, peak filling rate and time to peak filling rate were not different from those in normals. Even in patients with proximal right coronary lesions, the right ventricular ejection fraction was normal unless they had an inferior myocardial infarction. A decreased left ventricular ejection fraction and abnormal motion of the ventricular septum did not affect the right ventricular ejection fraction. The present results suggest that patients with an inferior myocardial infarction and proximal right coronary lesion often develop right ventricular systolic and diastolic dysfunction.
