Introduction and objectives: Although it is known that the presence of myocardial viability predicts an increase in ejection fraction after revascularization in patients with ischemic cardiomyopathy, little is known about other predictive factors. The aim of this study was to identify variables that can predict an increase in ejection fraction after coronary revascularization surgery in patients with ischemic cardiomyopathy and a viable myocardium.
Methods: The study included 30 patients (mean age 61.6 [11] years, one female) with ischemic cardiomyopathy (ejection fraction <or=40%) who fulfilled criteria for myocardial viability. All underwent ECG-gated single-photon emission computed tomography before and after surgery.
Results: An increase in ejection fraction >or=5% occurred after surgery in 17 of the 30 patients (56.6%). These patients were characterized by the presence of left main coronary artery disease (P< .004), a large number of grafts (P< .03), a high perfusion summed difference score (P< .012), a low end-diastolic volume (P< .013), and a low end-systolic volume (P< .01). An end-systolic volume <148 mL and a summed difference score >or=4 gave the best predictive model (P=.001, R2=0.73) for an increase in ejection fraction.
Conclusions: In patients with ischemic cardiomyopathy and a viable myocardium, the main determinants of an increase in ejection fraction after revascularization surgery were low levels of left ventricular remodeling and myocardial ischemia.