Cardiac Resynchronization Therapy in Preserved to Mildly Reduced Systolic Function
1Department of Cardiovascular Medicine, Mayo Clinic, 200 First Street Southwest, Rochester, MN 55905, USA.
Cardiac Electrophysiology Clinics
|February 6, 2019
Summary
Cardiac resynchronization therapy (CRT) benefits heart failure patients with low ejection fraction. This review explores CRT
Area of Science:
- Cardiology
- Medical Devices
- Heart Failure Management
Background:
- Cardiac resynchronization therapy (CRT) is established for heart failure patients with ejection fraction (EF) ≤35%.
- The current EF cutoff of 35% may exclude patients who could benefit from CRT.
- Left bundle branch block (LBBB) significantly impacts cardiac function.
Purpose of the Study:
- To review the detrimental effects of LBBB on cardiac function.
- To summarize evidence for CRT benefits in heart failure patients with EF >35%.
Main Methods:
- Literature review of studies on LBBB.
- Analysis of data on CRT efficacy in patients with varying EF levels.
Main Results:
- LBBB causes significant dyssynchrony and adverse ventricular remodeling.
- Emerging data suggest potential CRT benefits in patients with EF >35%.
Conclusions:
- The arbitrary 35% EF cutoff warrants re-evaluation.
- Expanding CRT eligibility criteria may improve outcomes for more heart failure patients.
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