The purpose of this study is to demonstrate that epicardial and transvenous left ventricular leads are safe and effective for cardiac resynchronization therapy in heart failure patients implanted with a CRT device.

This clinical trial is a multicenter, prospective, randomized, parallel, open study designed to compare epicardial left ventricular pacing to transvenous left ventricular pacing for delivering cardiac resynchronization therapy.

After a pre-implant baseline evaluation, patients will be randomized in a 1:1 fashion to one of two groups:

• Control group: resynchronization via a transvenous left ventricular lead (TVN CRT);
• Treatment group: resynchronization via an epicardial left ventricular lead (EPI CRT).

All patients taking part in this study will undergo the implantation of a CRT device with or without ICD back-up (depending on the physician's decision), with right atrial and right ventricular transvenous leads.

Patients will attend protocol scheduled visits before implant (pre-implant baseline evaluation), and post-implant: before hospital discharge, 6 weeks post-implant (optional visit), 3 months (optional visit), and 6 months after implant, time of study termination.

Inclusion Criteria:

• Have an approved indication for implantation of an CRT device (ESC guidelines , including any update);
• Have a stable pharmacological therapy.

Exclusion Criteria:

• Have a contra-indication to general anesthesia;
• Have a scheduled cardiac surgery;
• Have had a recent myocardial infarction, unstable angina or cardiac revascularization (PTCA or CABG) within 1 month of enrollment;
• Have a life expectancy of less than 6 months;
• Are unable to provide informed consent;
• Are unable to comply with the follow-up schedule and tests;
• Are minor (age below 18 years);
• Are pregnant or are planning for pregnancy in the next 6 months.