Relationship between radionuclide right ventricular ejection fraction and clinical status in patients with left ventricular dysfunction after myocardial infarction.

OBJECTIVE: To evaluate the influence of right ventricular (RV) function, determined by RV ejection fraction, on the clinical status of patients with ischemic heart disease and left ventricular (LV) EF under 40%. BACKGROUND: The role of RV function as a marker of prognosis in heart failure has been debated. We hypothesized that the degree of RV dysfunction is a determinant of the clinical status and outcome of patients with LV dysfunction after myocardial infarction. PATIENTS AND METHODS: 30 patients, 25 male, with previous myocardial infarction, more than 6 months age, were studied by equilibrium radionuclide angiography. Functional capacity was evaluated by cardiopulmonary exercise test with Naughton protocol. Patients were followed during a 12 month period for major clinical events: death or hospitalisation for congestive heart failure. Two groups of patients were considered according the value of RVEF (< or = 30% and > 30%). RESULTS: The values of EF were: LV = 25 +/- 7% and RV = 35 +/- 9%. Maximum oxygen consumption correlated with RVEF (r = 0.78, p < 0.001) but not with LVEF (r = 0.12, NS). The group of patients with RVEF > 30% had a greater exercise time (712 +/- 229 versus 441 +/- 208 seconds, p = 0.003), higher oxygen consumption (19.8 +/- 5.3 versus 13.5 +/- 3.3 ml/kg/min, p = 0.001) and oxygen consumption in relation to the maximum predicted for age and sex (71 +/- 19 versus 50 +/- 13%, p = 0.002). Cumulative frequency of major clinical events was greater in the group with RVEF < or = 30% (58% vs 6%, relative risk 3.14, 95% CI 1.23 to 5.05). There was no correlation between the values of LVEF and outcome. CONCLUSIONS: In this setting of ischemic LV dysfunction, the RVEF correlates with functional capacity in cardio-pulmonary exercise test and the presence of RV dysfunction is associated to a higher incidence of clinical events.