The main objective of the SONR-ECHO trial is to demonstrate that optimization of CRT parameters by SonR technology is able to increase the rate of CRT-D responders, based on significant LV reverse remodeling, as compared to Standard of Care settings.

This study will also evaluate the effectiveness of CRT-D SonR system as compared to Standard of care (SoC) programming methods in providing appropriate LV filling, as expected from the Ritter method.

This study will evaluate the effectiveness of CRT-D SonR system as compared to SoC programming methods to:

• Increase the rate of patients responding to CRT
• Provide appropriate hemodynamic cardiac effect, as expected from the Ritter method.

The identification of CRT responders, as defined by echocardiography, generally refers to a significant reduction of the LV End-Systolic Diameter (LVESD) and/or LVESV during Follow-Up (FUp).

Patients will be considered as responders to CRT if their LVESV decreased by > 15% after 6 months of CRT therapy as compared to baseline. The percentage of CRT responders will be compared between the two study arms.

SoC is defined as the standard CRT system programming/optimization method currently used by physicians in study centers and any method may be used in the study if considered as routine practice in the study center.

Inclusion Criteria:

• Eligible for implantation of a CRT-D device according to published relevant ESC and CCS guidelines ;
• In Sinus Rhythm;
• Have reviewed, signed and dated an informed consent

Exclusion Criteria:

• Previous implant with a pacemaker, an Implantable Cardioverter-Defibrillator or a CRT device (except upgrade from single chamber ICD with a fully functional defibrillation lead not under recall or surveillance);
• Persistent atrial arrhythmias (or cardioversion for Atrial Fibrillation) within the past month;
• Ventricular tachyarrhythmia secondary to reversible causes such as acute myocardial infarction (MI), digitalis intoxication, drowning, electrocution, electrolyte imbalance, hypoxia or sepsis, uncorrected at the time of the enrolment;
• Incessant ventricular tachyarrhythmia;
• Unstable angina, or acute MI, Coronary Artery Bypass-Grafting (CABG), or Percutaneous Transluminal Coronary Angioplasty (PTCA) within the past 4 weeks;
• Correctable valvular disease that is the primary cause of heart failure;
• Mechanical heart valve or indication for valve repair or replacement;
• Recent Cerebro-Vascular Accident (CVA) or Transient Ischemic Attack (TIA) (within the previous 3 months);
• Post heart transplant (patients who are waiting for a heart transplant are allowed in the study);
• Already included in another clinical study that could confound the results of this study;
• Life expectancy less than 1 year;
• Inability to understand the purpose of the study;
• Unavailability for scheduled follow-up or refusal to cooperate;
• Sensitivity to 1 mg Dexamethasone Sodium Phosphate (DSP);
• Age of less than 18 years;
• Pregnancy;
• Drug addiction or abuse;
• Under guardianship