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Updated: Jun 20, 2026

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
Slow conduction within lateral myocardial scar and response to cardiac resynchronization therapy
Nicolas Combes1, Stéphane Combes, Pierre Hausman
1Département de Rythmologie, Clinique Pasteur, Toulouse, France.
Abstract:
Cardiac resynchronization therapy (CRT) improves symptoms and survival in some selected heart failure patients. However, around 30% of patients still do not respond to CRT. In these patients, methodological approach of any potential cause of nonresponse should be reviewed. We describe the case of limited left ventricle (LV) myocardium capture by LV lead during biventricular pacing secondary to a slow conduction from LV lead impulse, located in a scar zone, and the benefit of interventricular delay optimization in this setting. This case emphasizes the interest of considering 12-lead electrocardiogram during management of patients with CRT.
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