Left ventricular dyssynchrony assessed by gated SPECT phase analysis is an independent predictor of death in patients with advanced coronary artery disease and reduced left ventricular function not undergoing cardiac resynchronization therapy.

PURPOSE: Left ventricular (LV) mechanical dyssynchrony (LVMD) was assessed by gated single-photon emission CT myocardial perfusion imaging (MPI) as an independent predictor of death from any cause in patients with known coronary artery disease (CAD) and reduced LV function.
METHODS: Between 2001 and 2010, 135 patients (64 ± 11 years of age, 84 % men) with known CAD, reduced LV ejection fraction (LVEF, 38 ± 15 %) and without an implanted cardiac resynchronization therapy device underwent gated MPI at rest. LV functional evaluation, which included phase analysis, was conducted to identify patients with LVMD. Kaplan-Meier survival curves were calculated for death of any cause during a mean follow-up of 2.0 ± 1.7 years. Uni- and multivariate Cox proportional hazards regression models were calculated to identify independent predictors of death from any cause.
RESULTS: Of the 135 patients, 30 (22 %) died during follow-up (18 cardiac deaths and 12 deaths from other causes). Kaplan-Meier curves showed a significantly shorter survival time in the patients with severely reduced LVEF (<30 %, n = 45) or with LVMD (n = 81, log-rank test P <0.005). Cox models identified LVMD, LVEF < 30 % and a total perfusion deficit at rest of ≥ 20 % as independent predictors of death from any cause. While patients with LVEF <30 % in conjunction with LVMD had similar survival times irrespective of whether they had early revascularization or medical therapy, those patients with LVEF ≥ 30% and LVMD who underwent revascularization had significantly longer survival.
CONCLUSION: In patients with known CAD and reduced LV function, dyssynchrony of the LV is an independent predictor of death from any cause.