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Updated: Aug 5, 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
Alternating bundle branch block: What is the mechanism?
Pulakesh Sinha1, Suvradip Dutta1, Subhrasekhar Chakraborty1
1Department of Cardiology Manipal Hospitals, EM Bypass, Kolkata, India.
Journal of Electrocardiology
|August 1, 2026
Summary
A patient with heart failure and complex heart rhythms received a pacemaker. Lead placement in the left bundle branch area improved conduction, addressing severe breathlessness.
Area of Science:
- Cardiology
- Electrophysiology
- Cardiac Pacing
Background:
- A 60-year-old male presented with severe left ventricular systolic dysfunction, multivessel coronary artery disease, and chronic kidney disease.
- Symptoms included New York Heart Association (NYHA) class III breathlessness.
- Electrocardiogram (ECG) revealed sinus rhythm with alternating bundle branch block and variable PR interval, suggesting complex conduction delays.
Purpose of the Study:
- To investigate the management of complex conduction abnormalities in a patient with significant cardiac comorbidities.
- To evaluate the efficacy of dual-chamber permanent pacemaker implantation with specific lead placement.
Main Methods:
- Diagnostic workup including ECG interpretation.
- Surgical implantation of a dual-chamber permanent pacemaker.
- Ventricular lead placement targeted at the left bundle branch area.
Main Results:
- Successful pacemaker implantation was achieved.
- The patient's presenting symptom of severe breathlessness was addressed.
- Lead placement in the left bundle branch area aimed to optimize conduction.
Conclusions:
- Dual-chamber permanent pacemaker implantation can be effective in managing complex conduction delays in patients with severe cardiac dysfunction.
- Left bundle branch area pacing may offer a beneficial pacing strategy in selected cases.
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