Prospective Randomized Trial Comparing TRIPLE Site ventriculAr Stimulation Versus Conventional Pacing in CRT canDidates

Cardiac resynchronization therapy (CRT) is a recommended treatment for selected patients with symptomatic heart failure (HF). Although most treated patients show a benefit from CRT, a lack of response is observed for about 25-30% of them whatever the response criteria used either based on the clinical status (NYHA class, Packer clinical composite score) or on ventricular remodeling parameters assessed by echography (Left ventricle end of systole volume). This rate has remained remarkably stable since the therapy started and has motivated many studies to better understand the underlying physiopathology and the CRT action mechanisms. Among the various research axes to improve CRT response and responders rate, increasing the number of pacing sites in an attempt to better homogenize the cardiac mechanical activity has been evaluated. A configuration with two RV leads and one LV lead was tested acutely in three studies. In all cases, it demonstrated a significant improvement of cardiac performance whether assessed by echographic parameters or LV dp/dt measurements. Additionally feasibility of this approach for long term CRT delivery was demonstrated during a previous study. First results with triple-site ventricular stimulation are encouraging and its clinical efficacy should now be tested on a larger population in order to conclude on its interest for CRT candidates.