Sudden cardiac arrest recorded during Holter monitoring: Prevalence, antecedent electrical events, and outcomes

Background Causative arrhythmias of sudden cardiac arrest (SCA) are changing in this age of improved coronary care. Objective The purpose of this study was to examine the frequency of terminal arrhythmias and the electrical events prior to SCA. Methods We analyzed 24-hour Holter recordings of 132 patients enrolled from 41 institutions who either died (n = 88) or had an aborted death (n = 44). The Holter recordings were obtained for diagnosing and evaluating diseases and arrhythmias in those without any episodes suggestive of SCA. Results In 97 patients (73%), SCA was associated with ventricular tachyarrhythmias and in 35 (27%) with bradyarrhythmias. The bradyarrhythmia-related SCA patients were older than those with a tachyarrhythmia-related SCA (70 ± 13 years vs 58 ± 19 years, P Conclusion The most frequent cause of SCA remains ventricular tachyarrhythmias. Advanced age and ST elevation before SCA are risk factors for mortality in tachyarrhythmia-related SCAs.