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Updated: Jun 4, 2026
12:45
Benefits of Cardiac Resynchronization Therapy in an Asynchronous Heart Failure Model Induced by Left Bundle Branch Ablation and Rapid Pacing
Published on: December 11, 2017
Exercise-induced left bundle branch block and subsequent mechanical left ventricular dyssynchrony--resolved with
Hidekazu Tanaka1, Mana Hiraishi, Tatsuya Miyoshi
1Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe, Japan. tanakah@med.kobe-u.ac.jp
Cardiovascular Ultrasound
|February 8, 2011
Summary
Pharmacological therapy improved ejection fraction and exercise-induced left bundle-branch block (LBBB) in a heart failure patient. Treatment enhanced cardiac function and delayed LBBB onset during exertion.
Area of Science:
- Cardiology
- Heart Failure Research
- Electrophysiology
Background:
- A 53-year-old male presented with heart failure symptoms, reduced ejection fraction (EF) of 35%, and normal QRS width at rest.
- Exertional dyspnea and chest discomfort indicated potential exercise-induced cardiac issues.
Observation:
- Treadmill exercise induced left bundle-branch block (LBBB) with a QRS width of 152 ms at a heart rate of 100 bpm.
- Significant mechanical dyssynchrony was observed during LBBB, with a radial strain time difference of 260 ms.
Findings:
- After five months of carvedilol and candesartan therapy, the patient's EF improved to 49%.
- LBBB was delayed until a heart rate of 126 bpm during subsequent exercise testing.
Implications:
- Pharmacological therapy may effectively manage heart failure with exercise-induced LBBB.
- This suggests that medical treatment can improve cardiac function and electrical stability in affected patients.
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