The evaluation of right ventricular function in acute myocardial infarction by xenon-133.

Right ventricular performance was assessed in 37 patients with acute myocardial infarction within two hours of admission to Coronary Care and compared to results in 21 normal volunteers and 12 patients undergoing coronary arteriography. Right ventricular ejection fraction (RVEF) was measured from gated xenon-133 scans. The normal range of RVEF (42.8 +/- 5.1%) was significantly higher than in the 30 patients with inferior infarction (26.3 +/- 10.9%; p less than 0.001) and was similar to that in patients with anterior infarct (40.6 +/- 5.4%; ns) and patients undergoing coronary arteriography (39.3 +/- 4.9%; ns). Fifteen of the patients with inferior infarct had clinical evidence of right ventricular dysfunction with a mean RVEF of 18.9 +/- 7.9%, significantly below the fifteen patients with no clinical evidence of right ventricular dysfunction (34.3 +/- 8.3%; p less than 0.001).