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Updated: May 26, 2026

A Model of Long-Term Ventricular Fibrillation in Isolated Rat Hearts
Published on: February 17, 2023
Fatal undersensing of ventricular fibrillation due to intermittent high-amplitude R waves
Ignasi Anguera1, Xavier Sabaté, Gemma Sugrañes
1Cardiovascular Diseases Group (Bellvitge Biomedical Research Institute) IDIBELL, Bellvitge University Hospital-ICS, L'Hospitalet de Llobregat, Barcelona, Spain. ignasi.anguera@gmail.com
Abstract:
A 48-year-old man was admitted after an episode of aborted sudden death with external defibrillation. An implantable cardioverter defibrillator implanted 2 years before for secondary prevention failed to sense properly an episode of ventricular fibrillation. Interrogation of the device showed large oscillatory changes of the amplitude of the local electrogram during ventricular fibrillation, causing undersensing and inappropriate refraining from shock therapy.
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