Utility of a new left ventricular asynchrony index as a predictor of reverse remodelling after cardiac resynchronization therapy

Abstract

Aims: The majority of tissue Doppler indexes proposed to predict left ventricular (LV) reverse remodelling in cardiac resynchronization therapy (CRT) reflects LV asynchrony as assessed in ejection phase. We evaluated the predictive value of a new strain-imaging parameter reflecting the total amount of time spent by 12 LV segments in contracting after aortic valve closure. Methods and results: Fifty-nine patients who fulfilled current treatment recommendations were studied before and 6 months after CRT. Time to tissue Doppler systolic peak velocity (Ts) and time exceeding aortic closure (ExcT) in strain curves were measured in 12 LV segments. Ts standard deviation (Ts-SD) and sum of ExcT of overall 12 LV segments (oExcT) were analysed. After 6 months, responders were defined according to ≥15% LV end-systolic volume reduction. Responders (47%) when compared with non-responders (53%) had significantly higher baseline Ts-SD and oExcT values. Receiver operating characteristic (ROC) curve analysis demonstrated that an optimal cutoff value of 760 ms for oExcT yielded 93.5% sensitivity and 82.8% specificity. For Ts-SD at the cutoff of 32 ms, 82% sensitivity and 39% specificity were obtained. Area under ROC was significantly larger for oExcT than for Ts-SD. Conclusion: o-ExcT is able to predict LV reverse remodelling after CRT. © The European Society of Cardiology 2006. All rights reserved.