Loss of ventricular preexcitation during noninvasive testing does not exclude high-risk accessory pathways: A multicenter study of WPW in children

C. A. Escudero
S. R. Ceresnak
K. K. Collins
R. H. Pass
P. F. Aziz
A. D. Blaufox, Zucker School of Medicine at Hofstra/Northwell
M. C. Ortega
B. C. Cannon
M. I. Cohen
B. E. Dechert
A. M. Dubin
K. S. Motonaga
M. R. Epstein
C. C. Erickson
S. B. Fishberger
G. J. Gates
C. A. Capone
L. Nappo
N. J. Kertesz
C. M. Janson


© 2020 Heart Rhythm Society Background: Abrupt loss of ventricular preexcitation on noninvasive evaluation, or nonpersistent preexcitation, in Wolff-Parkinson-White syndrome (WPW) is thought to indicate a low risk of life-threatening events. Objective: The purpose of this study was to compare accessory pathway (AP) characteristics and occurrences of sudden cardiac arrest (SCA) and rapidly conducted preexcited atrial fibrillation (RC-AF) in patients with nonpersistent and persistent preexcitation. Methods: Patients 21 years or younger with WPW and invasive electrophysiology study (EPS) data, SCA, or RC-AF were identified from multicenter databases. Nonpersistent preexcitation was defined as absence/sudden loss of preexcitation on electrocardiogram, Holter monitoring, or exercise stress test. RC-AF was defined as clinical preexcited atrial fibrillation with shortest preexcited R-R interval (SPERRI) ≤ 250 ms. AP effective refractory period (APERP), SPERRI at EPS, and shortest preexcited paced cycle length (SPPCL) were collected. High-risk APs were defined as APERP, SPERRI, or SPPCL ≤ 250 ms. Results: Of 1589 patients, 244 (15%) had nonpersistent preexcitation and 1345 (85%) had persistent preexcitation. There were no differences in sex (58% vs 60% male; P=.49) or age (13.3±3.6 years vs 13.1±3.9 years; P=.43) between groups. Although APERP (344±76 ms vs 312±61 ms; P<.001) and SPPCL (394±123 ms vs 317±82 ms; P<.001) were longer in nonpersistent vs persistent preexcitation, there was no difference in SPERRI at EPS (331±71 ms vs 316±73 ms; P=.15). Nonpersistent preexcitation was associated with fewer high-risk APs (13% vs 23%; P<.001) than persistent preexcitation. Of 61 patients with SCA or RC-AF, 6 (10%) had nonpersistent preexcitation (3 SCA, 3 RC-AF). Conclusion: Nonpersistent preexcitation was associated with fewer high-risk APs, though it did not exclude the risk of SCA or RC-AF in children with WPW.