The purpose of this study is to show that CRT(Cardiac Resynchronization Therapy) pacing in patients with severe functional MR (Mitral Regurgitation) who are not currently indicated for CRT will demonstrate chronic benefit of MR reduction( via echo measured MR/LA area and ERO per American Society of ECHO guidelines) and to show that CRT pacing is safe in these patients.

Approximately 50 patients will be randomized, followed and analyzed in this prospective study. Patients who meet all inclusion and no exclusion criteria will be enrolled and implanted with a CRT system. Baseline evaluation, which includes clinical symptom evaluation and an echocardiogram, will be performed at the time of randomization, which should occur as soon after device implant as possible but no later than 2 week post -implant. The baseline echocardiogram should be acquired prior to the device being programmed to the randomized setting. Repeat echocardiograms and scheduled follow-up evaluations will be performed at the end of each 3 month crossover period.

Inclusion Criteria:

• Patient is at least 18 years of age

• Patients with moderate-to-severe or severe functional MR.

  • EROA > 40 mm2 and an MR/LA > 40% (severe)
  • 30 ≤ EROA ≤ 40 mm2 and 30 ≤ MR/LA ≤ 40% (moderate-to-severe)

• Baseline rates of 50-90 beats per minute (patients with sinus rhythm) or AF

• QRS < 120 ms

• LVEF < 35%

• Willing to sign informed consent

• On standard stable heart failure medical regimen (beta blockers and ACE-I or ARBs) for at least 1 month before randomization, if tolerated

• Patient has the ability to understand the requirements of the study, including consent for use and disclosure of research-related information

• Patient has the ability to comply with study procedures and protocol, including required study visits

Exclusion Criteria:

• candidate for CRT or has a previously implanted CRT device
• previously implanted implantable pulse generators (IPG) or implantable cardioverter defibrillator (ICD) with at least 10 % pacing in the right ventricle
• patient has life expectancy <6 months
• patient is pregnant
• significant aortic stenosis
• uncontrolled hypertension
• mitral valve stenosis
• severe mitral valve calcification
• ruptured chordae tendinae or papillary muscle
• mitral valve leaflet disorders (i.e. endocarditis, lupus, tumors, rheumatic heart disease)
• chronic mitral leaflet degeneration (ie. Marfans)
• previous valve replacement or surgery
• IV inotropes or IV vasodilators
• candidate for mitral valve repair or replacement surgery within the next 6 months
• patient has in-hospital acute coronary syndrome (ACS) (NSTEMI/STEMI) prior to randomization
• patient has planned or elective percutaneous coronary intervention (PCI) or other non-cardiac surgery prior to randomization
• patient is currently enrolled in an investigational drug or device study
• patient is clinically unstable per PI assessment