Addition of a Second LV Pacing Site in CRT Nonresponders Rationale and Design of the Multicenter Randomized V3 Trial

BackgroundCardiac resynchronization therapy (CRT) is an effective treatment of heart failure (HF) in presence of a depressed left ventricular (LV) ejection fraction and a wide QRS complex. It is limited by a high proportion of nonresponders. Attempts have been made, in small studies, to increase the number of stimulation sites to optimize the resynchronization therapy. V3 is a planned multicenter, randomized trial whose objective is to evaluate the clinical benefit conferred by the addition of a second LV lead in nonresponders after at least 6 months of standard biventricular stimulation.Methods and ResultsA total of 84 patients will be enrolled in 11 French medical centers. Patients will be randomly assigned to receive either an additional LV lead (test group) or to keep their current stimulation system unchanged (control group). Enrollment is planned to begin in March 2010 and is expected to end within 1 year. The primary study end point will be the HF clinical composite score evaluated at 1 year follow-up. Secondary end points include degree of echocardiographic reverse remodeling and changes in clinical measurements.ConclusionsThe V3 trial will examine the clinical benefit conferred by the addition of a second LV lead in nonresponders to standard CRT.