Primary Results from the SMART AV DELAY Trial: A Randomized Trial Comparing Empiric, Echocardiographic Guided and Algorithmic AV Delay Programming in Cardiac Resynchronization Therapy (CRT) Kenneth A. Ellenbogen, MD, Michael R. Gold, PhD, MD, Bernd Lemke, MD, Ignacio F. Lozano, MD, Timothy E. Meyer, PhD, Suneet Mittal, MD, Jagmeet P. Singh, MD, Frank G. Spinale, PhD, MD, Kenneth M. Stein, MD, Jennifer E. Van Eyk, PhD, Alan D. Waggoner, MHS for The SMART-AV Trial Investigators.
Transcript
Primary Results from the SMART AV DELAY Trial: A Randomized Trial Comparing
Empiric, Echocardiographic Guided and Algorithmic AV Delay Programming in
Cardiac Resynchronization Therapy (CRT)
Primary Results from the SMART AV DELAY Trial: A Randomized Trial Comparing
Empiric, Echocardiographic Guided and Algorithmic AV Delay Programming in
Cardiac Resynchronization Therapy (CRT)
Kenneth A. Ellenbogen, MD, Michael R. Gold, PhD, MD, Bernd Lemke, MD, Ignacio F. Lozano, MD, Timothy E. Meyer, PhD,
Suneet Mittal, MD, Jagmeet P. Singh, MD, Frank G. Spinale, PhD, MD, Kenneth M. Stein, MD, Jennifer E. Van Eyk, PhD, Alan D.
Waggoner, MHS for The SMART-AV Trial Investigators.
Presenter Disclosure Information
Kenneth A. Ellenbogen, MDPrimary Results from the SMART AV DELAY Trial (Boston Scientific)
FINANCIAL DISCLOSURE:Research Grants: Boston Scientific, Medtronic, St. Jude Medical, Biosense Webster, Sanofi
Consulting / Advisory board: Boston Scientific, Biotronik, Medtronic, St. Jude Medical, Sorin Group, Sanofi, Cardionet, Atricare, EBR
Lectures: Boston Scientific, Biotronik, Medtronic, St. Jude Medical, Sorin Group, Sanofi
All devices used in the SMART-AV trial were Boston Scientific
SMART-AV (Background)SMART-AV (Background)
• In patients with heart failure and prolonged QRS duration, cardiac resynchronization therapy (CRT) reduces heart failure hospitalizations and prolongs survival compared with optimal medical therapy (OMT).
• Achieving the optimal outcome from CRT may be dependent on proper programming of the optimal atrioventricular (AV) delay.
• However, large scale randomized trials establishing the overall efficacy of CRT have differed widely in their approach to AV optimization.• CONTAK CD – No optimization• CARE-HF and MIRACLE – Doppler echocardiography of transmitral flow• COMPANION – algorithm based on the intrinsic AV interval and baseline
QRS
• The ASE proposed a mitral inflow method for routine AV optimization after CRT.
ObjectivesObjectives
• To compare three alternative AV optimization techniques and to assess the hypotheses that:
1) systematic AV delay optimization using echocardiography and/or the SD algorithm is superior to a fixed nominal AV delay as demonstrated by improved LV geometry after 6 months and
2) that programming according to SD is non-inferior to using echocardiography-determined AV delay optimization.
MethodsMethods
SMART-AV Inclusion• NYHA class III or IV• EF < 0.35• QRS >120ms• Expected to be in sinus rhythm at the
time of implant• Willing and capable of undergoing a
device implant and participating in all testing
• Receiving OPT
SMART-AV Exclusion• Complete heart block or unable to
tolerate pacing at VVI-40-RV for up to 14 days
• Previously received CRT
Primary Endpoint:• LVESV at 6 months
Secondary Endpoints:• 6 min walk, EF, NYHA Class,
LVEDV, QOL (MLWHF)
Statistics:• Continuous outcomes: general
linear model - F test• Categorical outcomes: risk
difference of proportions – Chi-squared test
• Applicable to primary, secondary and subgroup analyses
SMART-AV – Study DesignSMART-AV – Study Design
Enrollment and Implant CRT-D with SmartDelayProgram device to VVI-40-RV
Enrollment and Implant CRT-D with SmartDelayProgram device to VVI-40-RV
Post-Implant Visit (1 to 14 days post-implant)(1:1:1 Randomization, Programmed to DDD(R)60)
Post-Implant Visit (1 to 14 days post-implant)(1:1:1 Randomization, Programmed to DDD(R)60)
• The change in LVESV for the SD arm was no different than either the Echo or Fixed arms.
• There were no significant differences in the secondary structural or functional endpoints by optimization group.
• Patients with a wide QRS duration, LBBB, non-ischemic cardiomyopathy, and female gender responded more favorably to CRT therapy.
• In post-hoc analysis, females optimized with SD and Echo responded more favorably than females randomized to the Fixed arm.
• The routine use of AV optimization techniques as assessed in this trial is not warranted. However, this data does not exclude possible utility in selected patients who do not respond to CRT.
