Despite technological progresses the rate of non-responders to cardiac resynchronization therapy (CRT) remains close to 30%. This inconsistent effect of CRT might be due to incomplete resynchronization as dyssynchrony can persist in 25% to 30% of patients during CRT.

One might hypothesize that stimulating the ventricles at a single site is suboptimal and that stimulating multiple left ventricular (LV) or right ventricular (RV) sites may improve ventricular resynchronization and, consequently, its hemodynamic and clinical effects. First studies have suggested that 1 RV + 2 LV pacing sites configurations increased significantly dP/dt, pulse pressure, LV end-diastolic pressure, and is associated with more LV remodeling and better responder rate compared with pacing a single LV site. First studies with 2 RV+LV pacing sites configuration demonstrated increased dP/dt and cardiac output and a decrease of the cardiac dyssynchrony.

The present pilot trial was designed to examine the 6-month safety of biventricular stimulation with 2 right ventricular (RV) and 1 left ventricular (LV) leads - main objective- and to assess its clinical benefit.

Inclusion Criteria:

• Signed informed consent
• > 18 years old
• Cardiac resynchronization indication : New York Heart Association (NYHA) Class III/IV & QRS width > 120 ms milliseconds (ms) OR NYHA class II & QRS width > 150 ms
• Sinus rhythm
• First implant procedure

Exclusion Criteria:

• Permanent ventricular tachycardia
• Permanent pacing indication for 3rd degree atrioventricular (AV) block
• Diagnosed or suspected acute myocarditis
• Less than 1 year life expectancy related to a non-cardiovascular disease
• Impossibility to perform follow-up in the investigative center
• Pregnant woman
• Patient which may not cooperate to study procedures as evaluated by investigator
• Legally protected adult patient or patient unable to give an informed consent
• Patient enrolled in an other clinical trial
• Patient which does not benefit from a social protection system
• Renal insufficiency
• Patient registered on a heart transplant waiting list
• Disease and/or health condition which may interfere with study results