Left Bundle Branch Block-Induced Cardiomyopathy: Insights From Left Bundle Branch Pacing
Shunmuga Sundaram Ponnusamy1, Pugazhendhi Vijayaraman2
1Velammal Medical College, Madurai, India.
JACC. Clinical Electrophysiology
|April 4, 2021
Summary
Left bundle branch pacing (LBBP) effectively manages left bundle branch block (LBBB)-induced cardiomyopathy (LIC). This pacing method significantly improves QRS duration, cardiac function, and heart failure symptoms in patients with LIC.
Area of Science:
- Cardiology
- Electrophysiology
- Heart Failure Management
Background:
- Chronic left bundle branch block (LBBB) can lead to mechanical dyssynchrony and cardiomyopathy.
- Cardiac resynchronization therapy (CRT) with biventricular pacing (BVP) is a known treatment for LBBB-induced cardiomyopathy (LIC).
- Left bundle branch pacing (LBBP) is emerging as a promising alternative to BVP for LIC management.
Purpose of the Study:
- To evaluate the efficacy of left bundle branch pacing (LBBP) in patients diagnosed with left bundle branch block (LBBB)-induced cardiomyopathy (LIC).
Main Methods:
- Retrospective screening of patients undergoing CRT between 2018-2020.
- Inclusion of patients meeting criteria for LIC, with documentation of LBBB duration, CRT type, and response.
- Collection of pacing parameters, electrocardiographic, and echocardiographic data.
Main Results:
- LBBP was successfully performed in 13 out of 17 identified LIC patients.
- Significant reduction in QRS duration (167.8 to 110.4 ms) and improvement in repolarization parameters observed.
- Left ventricular ejection fraction improved significantly (30.4% to 57.4%), and NYHA functional class improved (3.1 to 1.2).
Conclusions:
- Left bundle branch pacing (LBBP) is a viable option for cardiac resynchronization therapy in patients with LIC.
- LBBP offers low and stable capture thresholds.
- It effectively corrects electrical and mechanical abnormalities associated with LBBB in LIC.
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