Relationship between radionuclide right ventricular ejection fraction and clinical status in patients with left ventricular dysfunction after myocardial infarction
Gil, V.M.; Ferreira, J.; Mendes, M.; Seabra-Gomes, R.
Revista Portuguesa de Cardiologia Orgao Oficial da Sociedade Portuguesa de Cardiologia 18(9): 791-798
1999
ISSN/ISBN: 0870-2551 PMID: 10536469 Document Number: 509556
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%. 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. 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%). 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. 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.