Comparison of AV Optimization Methods Used in Cardiac Resynchronization Therapy (CRT)

SMART-AV is a randomized, multi-center, double-blinded, non-significant risk, three-armed trial that will investigate the effects of optimizing AV delay timing in heart failure patients receiving CRT-D therapy. Patients will be randomized in a 1:1:1 ratio using randomly permuted blocks within each center. The study will compare chronic changes in structural and functional outcomes in CRT-D patients randomized to AV delay set as fixed, set with SmartDelay or determined by echocardiography. Patients will be followed at enrollment, implant, post-implant, 3-months post-implant and 6-months post-implant.

Inclusion criteria

• Patients who meet current indications for a BSC CRT-D device with the SmartDelay algorithm
• Patients who are willing and capable of undergoing a device implant and participating in all testing associated with the SMART-AV Study
• Patients who are on optimal and stable pharmacologic therapy
• Patients who are expected to be in sinus rhythm at the time of implant
• Patients who have a life expectancy of more than 360 days, per physician's discretion
• Patients who are geographically stable and willing to comply with the required follow-up schedule
• Patients who are 18 years of age or above, or of legal age to give informed consent specific to state and national law

Exclusion criteria

• Patients who are in complete heart block, or who otherwise are unable to tolerate pacing at VVI-40 RV for up to 14 days
• Patients undergoing an upgrade of a pacemaker or implantable cardioverter-defibrillator who are unable to tolerate pacing at VVI-40 RV for up to 14 days
• Patients who have previously received cardiac resynchronization therapy
• Patients who are expected to receive a heart transplant or have other cardiac surgeries or procedures planned during the course of the study
• Patients who currently have or who are likely to receive a tricuspid valve prosthesis
• Patients who have a neuromuscular, orthopedic, or other non-cardiac condition that prevents normal, unsupported walking
• Patients who are pregnant or planning to become pregnant during the study
• Patients who are currently enrolled in another investigational study or registry that would directly impact the treatment or outcome of the current study