advances for treating in-hospital cardiac arrest: safety and effectiveness of a new automatic external cardioverter-defibrillator

The purpose of this study was to prospectively analyze the performance and safety of a new programmable, fully automatic external cardioverter-defibrillator (AECD) in a European multicenter trial. Although, the response time to cardiac arrest (CA) is a major determinant of mortality and morbidity, in-hospital strategies have not significantly changed during the last 30 years. Patients (n = 117) at risk of CA in monitored wards (n = 51) and patients undergoing electrophysiologic testing or implantable cardioverter-defibrillator (ICD) implantation (n = 66) were enrolled. The accuracy of the automatic response of the device to any change of rhythm (lasting >1 s and >4 beats) was confirmed by reviewing the simultaneously recorded Holter data and the programmed parameters. During 1,240 h, 1,988 episodes of rhythm changes were documented. A total of 115 episodes lasted ≥10 s or needed treatment (pacing, n = 32; ICD, n = 51; AECD, n = 35) for termination. The device detected ventricular tachyarrhythmias with a sensitivity of 100% and specificity of 97.6% (true negatives, n = 1,454; true positives, n = 499; false positives, n = 35; false negatives, n = 0). The false positives were all caused by T-wave oversensing during ventricular pacing. There were no complications or adverse events. The mean response time was 14.4 s for those episodes needing a full charge of the capacitor. This new AECD is safe and effective in detecting, monitoring, and treating spontaneous arrhythmias. This fully automatic device shortens the response time to treatment, and it is likely that it will significantly improve the outcome of patients with in-hospital CA.