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Updated: Jul 14, 2026
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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
Improvement in cardiac adrenergic function post biventricular pacing for heart failure.
Paul A Gould1, Grace Kong, Victor Kalff
1Wynn Department of Metabolic Cardiology, Baker Heart Research Institute, Central, Melbourne VIC, Australia.
Summary
Biventricular (BiV) pacing improves cardiac sympathetic nerve activity in heart failure (HF) patients. This is shown by enhanced (123)I-MIBG uptake, suggesting a mechanism for BiV pacing
Area of Science:
- Cardiology
- Nuclear Medicine
- Heart Failure Management
Background:
- Heart failure (HF) is a complex condition often associated with impaired cardiac sympathetic activity.
- Biventricular (BiV) pacing is a therapeutic option for select HF patients, but its effects on sympathetic function require elucidation.
Purpose of the Study:
- To investigate the impact of BiV pacing on cardiac sympathetic nerve activity in patients with heart failure.
- To assess changes in (123)I-MIBG uptake as a marker of sympathetic innervation.
Main Methods:
- A double-blinded, crossover study involving 10 HF patients.
- Patients received two weeks of BiV pacing followed by two weeks of BiV pacing inactivation, or vice versa.
- Cardiac sympathetic activity was evaluated using (123)I-MIBG scintigraphy and the 6-minute walk test.
Main Results:
- BiV pacing significantly improved cardiac (123)I-MIBG uptake in both early and late phases (p=0.03).
- Pulmonary (123)I-MIBG uptake also showed significant improvement (p=0.009).
- A trend towards improvement was observed in the 6-minute walk test and systolic blood pressure (p=0.09).
Conclusions:
- BiV pacing is associated with long-term improvements in cardiac sympathetic nerve activity in stable HF patients.
- Enhanced (123)I-MIBG uptake suggests a potential mechanism underlying the morbidity and mortality benefits of BiV pacing.
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