Sudden cardiac arrest associated with early repolarization
Michel Haïssaguerre1, Nicolas Derval, Frederic Sacher
1Université Bordeaux, Hôpital Haut-Lévêque, Bordeaux-Pessac, France. michel.haissaguerre@chu-bordeaux.fr
The New England Journal of Medicine
|May 9, 2008
Summary
Early repolarization, an electrocardiographic finding, is more common in patients with idiopathic ventricular fibrillation. This suggests a potential link between early repolarization and cardiac arrest risk.
Area of Science:
- Cardiology
- Electrophysiology
- Public Health
Background:
- Early repolarization (ECG) is typically benign.
- Its role in cardiac arrhythmias and sudden cardiac arrest (SCA) is unclear.
Purpose of the Study:
- To investigate the association between ECG early repolarization and idiopathic ventricular fibrillation (IVF).
Main Methods:
- Retrospective review of 206 IVF case subjects and 412 controls.
- ECG early repolarization defined as QRS-ST junction elevation ≥0.1 mV.
- Follow-up included implantable defibrillator monitoring.
Main Results:
- Early repolarization was significantly more prevalent in IVF cases (31%) versus controls (5%).
- IVF cases with early repolarization had higher rates of recurrent ventricular fibrillation (HR 2.1).
- Early repolarization was associated with male sex and syncope in IVF patients.
Conclusions:
- ECG early repolarization is more prevalent in patients with IVF.
- This finding suggests a potential clinical association with cardiac arrest risk.
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