Affiliation:
1. Department of Cardiology and Nephrology Hirosaki University Graduate School of Medicine Hirosaki Japan
2. Department of Advanced Management of Cardiac Arrhythmias Hirosaki University Graduate School of Medicine Hirosaki Japan
3. Department of Cardiac Remote Management System Hirosaki University Graduate School of Medicine Hirosaki Japan
4. Department of the Advanced Therapeutics for Cardiovascular Diseases Hirosaki University Graduate School of Medicine Hirosaki Japan
Abstract
AbstractIntroductionDuring ventricular pacing, a fusion of atrial activation may occur owing to the simultaneous retrograde conduction of the atrioventricular (AV) node and accessory pathway (AP), potentially leading to an inaccurate mapping of the atrial AP insertion site.ObjectiveWe tested the hypothesis that landiolol, an ultra‐short‐acting intravenous β1‐blocker, could dissociate a fusion of atrial activation.MethodsWe conducted a prospective before‐and‐after study to investigate the effect of landiolol on retrograde conduction via the AV node and AP. We enrolled 21 consecutive patients with orthodromic AV reciprocating tachycardia who underwent electrophysiological studies at our hospital between January 1, 2018, and August 31, 2020.ResultsSix patients exhibited a fusion of atrial activation. After landiolol administration (10 μg/kg/min), the effective refractory period was unchanged in AP (280 [240–290] ms vs. 280 [245–295] ms, p = .91), whereas that of the AV node was prolonged (275 [215–380] ms vs. 332 [278–445] ms, p = .03). The Wenckebach pacing rate via retrograde AV node decreased after landiolol administration (180 [140–200] beats per minute [bpm] vs. 140 [120–180] bpm, p = .02). Thus, landiolol decreased the minimum ventricular pacing rate required to dissociate a fusion of atrial activation (180 [160–200] bpm vs. 140 [128–155] bpm, p = .007). Radiofrequency catheter ablation under landiolol administration successfully eliminated AP in all patients during ventricular pacing without complications or recurrence.ConclusionLandiolol inhibited the AV node without affecting the AP and helped dissociate a fusion of atrial activation at a lower ventricular pacing rate.
Subject
Cardiology and Cardiovascular Medicine