Low-dose dobutamine stress echo for reverse remodeling prediction after cardiac resynchronization

PurposeCardiac resynchronization therapy (CRT) is a valuable option for patients with heart failure and wide QRS to reduce electromechanical dyssynchrony (DYS). High non-responders rate (30%) urges the need to improve selection of candidates for CRT. We hypothesized that low-dose dobutamine stress echocardiography (DSE) can help unmask dyssynchronous motion. The aim of this study is comparison between dyssynchrony index at rest and during low-dose dobutamine stress to predict left ventricular reverse remodeling after CRT.Patients and methodsProspectively, 57 consecutive patients (37 male) aged 61.8 ± 9 who qualified for CRT according to current guidelines were enrolled. Two dimensional echocardiography and tissue Doppler imaging (TDI) were performed before and 6 month after CRT to assess reverse remodeling (rLV). Additionally DSE was performed before CRT. DYS was assessed at rest (DYSr) and peak DSE (DYSd) separately, as a difference between time to peak systolic velocity (Ts) of septum and lateral wall. Ts was corrected for heart rate.ResultsrLV defined as decrease ≥15% of LVESV at follow-up was found in 38 (67%) patients. DYSr and DYSd were independent predictors of rLV (OR = 1.04, Cl  ± 1.02–1.06, p < 0.02 and OR = 1.05, Cl ± 1.03–1.08, p < 0.0002 respectively). ROC analysis found that DYSr > 42 ms and DYSd > 59 ms had sensitivity of 70% and 87%, specificity of 61% and 78%, and accuracy of 70% and 84% respectively for prediction of reverse remodeling LV. Area under Receiver Operating Characteristic Curve for DYSd was higher than for DYSr (0.89 vs 0.71, p < 0.007).ConclusionExercise intraventricular dyssynchrony assessed by dobutamine stress echo is a strong independent predictor of cardiac resynchronization therapy response.