Dynamic Analysis of Cardiac Rhythms for Discriminating Atrial Fibrillation from Lethal Ventricular Arrhythmias.
Circ Arrhythm Electrophysiol. 2013 May 16;
Authors: Demazumder D, Lake DE, Cheng A, Moss TJ, Guallar E, Weiss RG, Jones S, Tomaselli GF, Moorman JR
Abstract
BACKGROUND: -Implantable cardioverter-defibrillators (ICDs), the first-line of therapy for preventing sudden cardiac death in high-risk patients, deliver "appropriate" shocks for termination of ventricular tachycardia/fibrillation (VT/VF). A common shortcoming of ICDs is imperfect rhythm discrimination, resulting in the delivery of "inappropriate" shocks for atrial fibrillation (AF). An underexplored area for rhythm discrimination is the difference in dynamic properties between AF and VT/VF. We hypothesized that the higher entropy of rapid cardiac rhythms preceding ICD shocks distinguishes AF from VT/VF. METHODS AND RESULTS: -In a multicenter, prospective, observational study of patients with primary prevention ICDs, 119 patients received shocks from ICDs with stored, retrievable intracardiac electrograms. Blinded adjudication revealed shocks were delivered for VT/VF (62%), AF (23%), and supraventricular tachycardia (15%). Entropy estimation of only 9 ventricular intervals prior to ICD shocks accurately distinguished AF (ROC curve area 0.98; 95% CI 0.93-1.0) and outperformed contemporary ICD rhythm discrimination algorithms. CONCLUSIONS: -This new strategy for AF discrimination based on entropy estimation expands on simpler concepts of variability, performs well at fast heart rates, and has potential for broad clinical application.
PMID: 23685539 [PubMed - as supplied by publisher]