This prospective, randomized, single blind, multi-centre study will examine the effect of the right ventricular (RV) lead location in patients implanted with a cardiac resynchronization defibrillator.

1. Purpose :

   To compare the effect of RV mid-septal (RVS) versus RV apical (RVA) lead location on left ventricular reverse remodeling in patients indicated for cardiac resynchronization therapy device (CRT-D) over a period of 6 months and to evaluate the clinical outcome of the RVS versus RVA pacing, over a period of 12 months.

2. Objectives:

The primary objective is to demonstrate that there is no difference between the two groups (RVA vs. RVS) in the change of left ventricular end systolic volume (LVESV), between baseline and 6 months.

The secondary objectives are to evaluate the percentage of "echo-responders" plus additional clinical and safety outcomes.

This prospective, randomized, multi-centre, single-blind with 2 parallel arms, non-inferiority study will be conducted in approximately 25 study centres in Europe. The patients will be randomized in a 1:1 ratio. A maximum of 416 patients will be enrolled in this study.

All eligible patients will be followed through baseline, randomisation, pre discharge, 1, 6 and 12 months post-implant. Enrolment is expected to be completed in 18 months. The total duration of the study is expected to be approximately 30 months.

Inclusion Criteria:

• Accepted CRT indication according to ESC with

  1. Documented LVEF </= 35% in last 3 months
  2. Documented LVEDD ≥ 55 mm or LVEDD > 30 mm/m2, or LVEDD >30 mm/m (height) in last 3 months
  3. QRS ≥120 ms documented on ECG recording during hospitalisation
  4. NYHA Class III or ambulatory class IV stable for the last month previous enrolment

• Or the previous criteria 1 and 2 and a transient episode in NYHA class III or IV with prior HF hospitalization or intravenous decongestive therapy (IV diuretics, IV neseritide or IV inotropes) in an "out-patient" setting within the year previous enrolment and stabilization to NYHA class II for the last month with a QRS ≥150 ms documented on ECG recording during hospitalisation

• ICD indication (class I or II A)

• Optimal and stable medication for at least one month (except for diuretics stable for minimum 1 week) based on ESC guidelines before the enrolment

• Chronic heart failure (> 3 months) stable for the last month previous enrolment

• Stable sinus rhythm at the enrolment

• Willing and capable of providing informed consent

Exclusion Criteria

• Defibrillation testing not planned during the implant procedure due to a poor haemodynamic or clinical status or other reasons
• Have persistent atrial fibrillation (AF) or atrial flutter (i.e, can be terminated with medical intervention, but does not terminate spontaneously) within 1 month prior inclusion
• Documented AF within 1 month prior enrolment
• Life expectancy < 12 months or expected to undergo heart transplant within the next 12 months
• Uncontrolled blood pressure (Systolic BP > 160 mmHg or Diastolic BP > 85 mmHg)
• Hospitalization for HF or intravenous inotropic drug treatment within 1 month prior enrolment
• Cardiac surgery, per cutaneous transluminal angioplasty (PTCA), myocardial infarction (MI), unstable or severe angina or stroke during last 3 months prior enrolment
• Previously implanted pacemaker or ICD
• Uncorrected primary valvular disease
• Prosthetic tricuspid valve
• Nursing women or of childbearing potential who are, or might be pregnant at the time of the study
• Enrolled in any on-going study (including pharmacologic trial).