SPECT-derived myocardial viability in patients with stable coronary artery disease and left ventricular dysfunction selected for surgical revascularization

Background and Aims: To study the interrelation between left ventricular (LV) systolic function and myocardial viability in patients with stable coronary artery disease (SCAD) and LV dysfunction (LVD) selected for coronary artery bypass grafting (CABG). Methods: The cross-sectional study enrolled 21 SCAD patients with LVD selected for CABG (mean age 58±8 years; 18 males). Among them, 9 patients were selected for isolated CABG, and 12 patients – CABG with adjunct LV aneurism and/or valve surgery. The extent (%) of LV viable myocardium (VM) was assessed by single-photon emission computed tomography (SPECT). LV ejection fraction (EF) was measured by both transthoracic echocardiography (TTE) and SPECT. Results: The extent of LVVM in the whole sample of patients was (hereinafter – median, interquartile range) 56 % (49-64 %) (min-max 40-70 %) (n=21). SPECT-derived LVEF was 24 % (17-28 %) (min-max 10-34 %) (n=19). At the same time, TTE-derived LVEF was 34 % (27-38 %) (min-max 11-44 %) (n=21). Both SPECT- and TTE-derived LVEF correlated significantly with each other (ρ = 0,490; р=0,033) (n=19). However, we did not reveal significant correlations of LVVM extent with both SPECT- and TTE-derived LVEF. Conclusions: Among the enrolled SCAD patients with LVD undergoing CABG, both SPECT- and TTE-derived LVEF, generally, correlated with each other. At the same time, the SPECT-derived percentage of LVVM didn’t correlate with LVEF evaluated by both methods. Higher levels of LVVM might be considered as an important additional criterion to perform surgical revascularization.