Introduction: Patients’ selection for CRT is a matter of concern since the non-responders rate remains high (30%). Gated-SPECT myocardial perfusion imaging with phase analysis evaluates dyssynchrony in an automatic and reliable way. We aimed to determine its value in predicting CRT-induced reverse remodeling.
Methods: We performed GSPECT with technetium-99m tetrofosmin before and 21±9 months after CRT implantation. Left ventricular (LV) volumes, ejection fraction (EF) and LV dyssynchrony were assessed. Reverse remodeling was defined as end-systolic LV reduction ?15% or EF increase >5% (absolute value).
Results: Of the 20 patients evaluated (68±9 years, 90% male), 9 (45%) had reverse remodeling. The reduction of dyssynchrony in response to CRT as assessed by phase standard deviation (PSD) was a strong predictor of CRT response: responders had higher reductions of PSD (15.7±15.8 vs. -4.6±18.2, p=0.025), the reduction of PSD correlated positively with EF increase (R=0.467,p=0.038) and PSD had good accuracy in predicting reverse remodeling (AUC=0.80, 95%CI 0.60-0.99, p=0.025).
Conclusions: The reduction of dyssynchrony as assessed by Gated-SPECT is a valuable predictor of CRT response.