Cardiac memory in patients with Wolff-Parkinson-White syndrome: noninvasive imaging of activation and repolarization before and after catheter ablation.
BACKGROUND
Cardiac memory refers to a change in ventricular repolarization induced by and persisting for minutes to months after cessation of a period of altered ventricular activation (eg, resulting from pacing or preexcitation in patients with Wolff-Parkinson-White syndrome). ECG imaging (ECGI) is a novel imaging modality for noninvasive electroanatomic mapping of epicardial activation and repolarization.


RESULTS
Fourteen pediatric patients with Wolff-Parkinson-White syndrome and no other congenital disease, were imaged with ECGI a day before and 45 minutes, 1 week, and 1 month after successful catheter ablation. ECGI determined that preexcitation sites were consistent with sites of successful ablation in all cases to within a 1-hour arc of each atrioventricular annulus. In the preexcited rhythm, activation-recovery interval (ARI) was the longest (349+/-6 ms) in the area of preexcitation leading to high average base-to-apex ARI dispersion of 95+/-9 ms (normal is approximately 40 ms). The ARI dispersion remained the same 45 minutes after ablation, although the activation sequence was restored to normal. ARI dispersion was still high (79+/-9 ms) 1 week later and returned to normal (45+/-6 ms) 1 month after ablation.


CONCLUSIONS
The study demonstrates that ECGI can noninvasively localize ventricular insertion sites of accessory pathways to guide ablation and evaluate its outcome in pediatric patients with Wolff-Parkinson-White syndrome. Wolff-Parkinson-White is associated with high ARI dispersion in the preexcited rhythm that persists after ablation and gradually returns to normal over a period of 1 month, demonstrating the presence of cardiac memory. The 1-month time course is consistent with transcriptional reprogramming and remodeling of ion channels.
Ghosh
Subham
S
Cardiac Bioelectricity and Arrhythmia Center, Department of Biomedical Engineering, Washington University, St Louis, MO, USA.
Rhee
Edward K
EK
Avari
Jennifer N
JN
Woodard
Pamela K
PK
Rudy
Yoram
Y
D000200:Action Potentials / Q000502:physiology; D000293:Adolescent; D000465:Algorithms; D017115:Catheter Ablation; D002648:Child; D004562:Electrocardiography / Q000379:methods*; D005260:Female; D006325:Heart Atria; D006329:Heart Conduction System / Q000502:physiology; D006352:Heart Ventricles; D006801:Humans; D008297:Male; D009200:Myocardial Contraction / Q000502:physiology; D011237:Predictive Value of Tests; D014057:Tomography, X-Ray Computed; D014927:Wolff-Parkinson-White Syndrome / Q000175:diagnosis* / Q000503:physiopathology / Q000601:surgery*