Same morphology of ventricular premature complexes triggering repeated ventricular fibrillation
Juan José Sánchez-Muñoz1, Arcadio García-Alberola, Juan Martínez-Sánchez
1Arrhythmia Unit, University Hospital Virgen de la Arrixaca, Murcia, Ctra. Madrid-Cartagena, 30120, El Palmar, Murcia, Spain. juanjosanchezmunoz@me.com
Summary
Ventricular premature complexes (VPCs) initiating ventricular fibrillation (VF) episodes in the same patient consistently show similar morphologies, suggesting a stable origin. Coupling intervals vary depending on the time between VF events.
Area of Science:
- Cardiology
- Electrophysiology
- Medical Devices
Background:
- Ventricular fibrillation (VF) can be initiated by ventricular premature complexes (VPCs) of a single morphology.
- Characteristics of VPCs initiating VF over extended periods remain unclear.
Purpose of the Study:
- To compare morphologies and coupling intervals of VPCs that initiate VF episodes at different time points.
- Investigate the stability of VPC origin triggering VF.
Main Methods:
- Review of International Classification of Diseases (ICD) unit follow-up database.
- Analysis of electrocardiogram (ECG) recordings from patients with at least two spontaneous VF episodes.
- Evaluation of coupling intervals and morphology of the initiating VPC.
Main Results:
- Nine out of 300 ICD patients experienced multiple spontaneous VF episodes.
- VPCs initiating VF maintained the same morphology across all episodes for each patient.
- VPC coupling intervals were consistent during arrhythmic storms but more variable between long-interval VF episodes.
Conclusions:
- VPCs triggering VF in the same patient exhibit similar morphologies, indicating a consistent origin.
- Morphological similarity suggests a stable arrhythmogenic substrate for initiating VF.
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