Left Ventricular Reverse Remodeling in Cardiac Resynchronization Therapy and Long-Term Outcomes
Syed Y Naqvi1, Anas Jawaid1, Katherine Vermilye1
1University of Rochester Medical Center, Rochester, New York.
JACC. Clinical Electrophysiology
|September 21, 2019
Summary
Cardiac resynchronization therapy (CRT) improves survival in patients with left bundle branch block (LBBB) by reducing left ventricular end-systolic volume (LVESV). However, CRT offers no survival benefit and may be harmful in patients without LBBB.
Area of Science:
- Cardiology
- Electrophysiology
- Heart Failure Management
Background:
- Left ventricular reverse remodeling predicts outcomes in cardiac resynchronization therapy (CRT) patients.
- The long-term survival impact of reverse remodeling remains incompletely understood.
Purpose of the Study:
- To assess the association between left ventricular end-systolic volume (LVESV) improvement with CRT and mortality.
- To determine if left bundle branch block (LBBB) modifies this association.
Main Methods:
- Echocardiographic LVESV changes were analyzed in CRT with a defibrillator (CRT-D) patients (n=752) from the MADIT-CRT trial.
- Patients were stratified by LBBB presence and compared to implantable cardioverter-defibrillator (ICD)-only patients (n=684) regarding long-term mortality.
Main Results:
- In LBBB patients, >35% LVESV reduction significantly lowered mortality risk (HR: 0.34) and heart failure events.
- Patients without LBBB showed no survival benefit from CRT-D, with a >3-fold increased mortality risk in those with minimal remodeling.
- Risk reduction for heart failure events was consistent across LVESV quartiles in LBBB patients.
Conclusions:
- CRT-D-induced LVESV reduction at 1 year is linked to long-term survival benefits in patients with LBBB.
- In patients without LBBB, CRT-D does not improve survival and may increase mortality risk, even with reverse remodeling.
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