Adaptive Cardiac Resynchronization Therapy Study (aCRT)

• Percentage of patients with improved heart failure outcomes Clinical Composite Score [ Time Frame: randomization to six month visit ] [ Designated as safety issue: No ]
• Correlation between aortic velocity time integral (AoVTI) at Adaptive CRT and echo-optimized device settings (AoVTI is an echocardiographic representative of stroke volume and cardiac performance.) [ Time Frame: randomization visit and six month visit ] [ Designated as safety issue: No ]
• Percentage of patients with a safety event (inappropriate AV or VV delay settings related to the aCRT feature) [ Time Frame: 6 months post randomization ] [ Designated as safety issue: No ]

• Right ventricular pacing percentage [ Time Frame: implant to six months post randomization ] [ Designated as safety issue: No ]
• Change in left ventricular end systolic volume index (LVESVi) [ Time Frame: baseline to six month visit ] [ Designated as safety issue: No ]
• Change in left ventricular ejection fraction (LVEF) [ Time Frame: baseline to six month visit ] [ Designated as safety issue: No ]
• Change in New York Heart Association (NYHA) classification [ Time Frame: baseline to six month visit ] [ Designated as safety issue: No ]
• Change in distance walked during the six minute hall walk [ Time Frame: baseline to six month visit ] [ Designated as safety issue: No ]
• Change in quality of life measured by the Minnesota Living With Heart Failure Questionnaire (MLWHF) [ Time Frame: baseline to six month visit ] [ Designated as safety issue: No ]

The purpose of this study is to show that Adaptive CRT is at least as good at optimizing a patient's cardiac resynchronization therapy (CRT) as the current method of using an echocardiogram. Adaptive CRT (aCRT) is an implantable heart failure device feature that attempts to optimize CRT without echocardiographic testing.

• Device: Cardiac Resynchronization Therapy-Defibrillator (CRT-D)
  Market approved Medtronic Vision 3D™ CRT-D implantable device (Consulta® CRT-D, Maximo II® CRT-D, or Concerto II® CRT-D)
  Other Names:

  • Consulta® CRT-D
  • Maximo II® CRT-D
  • Concerto II® CRT-D
• Other: Adaptive CRT (aCRT) Pacing
  Adaptive CRT pacing software adjusts how the device paces the heart based on the patient's current heart status
  Other Name: AdaptivCRT

• Experimental: Adaptive CRT (aCRT) Pacing
  Cardiac resynchronization therapy (CRT) with adaptive pacing
  Interventions:

  • Device: Cardiac Resynchronization Therapy-Defibrillator (CRT-D)
  • Other: Adaptive CRT (aCRT) Pacing
• Active Comparator: Standard Biventricular Pacing
  Cardiac resynchronization therapy (CRT) with biventricular pacing only (without adaptive pacing)
  Intervention: Device: Cardiac Resynchronization Therapy-Defibrillator (CRT-D)

Inclusion Criteria:

• Subject is willing to sign and date the study Informed Consent form
• Subject is at least 18 years of age (or older, if required by local law)
• Subject is expected to remain available for at least six months of follow-up visits
• Subject is indicated for a study device that will be implanted within 30 days after signing the Informed Consent form
• Subject has an intrinsic QRS duration greater than or equal to 120 milliseconds (documented within 30 days prior to enrollment)
• Subject has a left ventricular ejection fraction less than or equal to 35 percent (method per physician discretion) (documented within 180 days prior to enrollment)
• Subject is diagnosed with New York Heart Association (NYHA) class III or IV (within 30 days prior to enrollment) despite optimal medical therapy which is defined as: ACE-inhibitor (Angiotensin-Converting Enzyme) or Angiotensin II Receptor Blocker (ARB), if tolerated, for at least one month prior to implant, AND beta-blocker for at least three months preceding implant, if tolerated, and stable for one month, OR subject has an urgent medical need for an implantable cardioverter defibrillator (ICD) that precludes waiting the one or three months for the medication requirements for ACE inhibitor, ARB or beta-blocker

Exclusion Criteria:

• Subject has chronic (permanent) atrial arrhythmias for which pharmacological therapy and/or cardioversion have been unsuccessful or have not been attempted
• Subject has existing CRT system
• Subject has non-intact or unstable leads
• Subject has medical conditions that would limit study participation (per physician discretion)
• Subject is enrolled in one or more concurrent studies that would confound the study results of this study as determined by Medtronic
• Subject has unstable angina, or experienced an acute myocardial infarction (MI) or received coronary artery revascularization (CABG) or coronary angioplasty (PTCA) (documented within 30 days prior to enrollment)
• Subject has a mechanical right heart valve or is scheduled to undergo valve repair or valve replacement during the course of the study
• Subject is post-heart transplant (subjects on the heart transplant list for the first time are not excluded)
• Subject has a limited life expectancy that would not allow completion of the 6 month visit
• Subject is pregnant (In the United States, all women of child-bearing potential must undergo a pregnancy test within seven days prior to aCRT download into device)
• Subject meets the exclusion criteria required by local law