Abstract 13992: The Impact of Dexmedetomidine on the Cardiac Electrophysiological Properties in Patients With Paroxysmal Atrial Fibrillation
Background: Dexmedetomidine (DEX), a selective α2-adrenergic receptor agonist, has increasingly been used as a sedative during ablation of atrial fibrillation. DEX is known to have some suppressive effects on the cardiac conduction system, however, that has not yet been extensively assessed in human adults. We aimed to perform a detailed analysis of the impact of DEX on the cardiac electrophysiological properties in patients with paroxysmal atrial fibrillation (AF).
Methods and Results: We measured the cardiac electrophysiological properties in adult patients (65±11 years) undergoing ablation of paroxysmal AF who were assigned to receive DEX (10 minutes of a loading at a dose of 6μg/kg/min followed by a maintenance dose of 0.6μg/kg/min; N=120) or those who were assigned not to receive any sedative (N=120). The patients with DEX were more likely than those without to have a longer sinus cycle length (943±190 vs. 802±142ms; p<0.001), greater corrected sinus node recovery time (547±334 vs. 441±239ms; p<0.001), and more prolonged atrial effective refractory period (234±35 vs. 220±33ms; p<0.001). The AH interval (103±24 vs. 91±20ms; p<0.001), atrioventricular (AV) nodal effective refractory period (324±70 vs. 268±58ms; p<0.001), and Wenckebach cycle length (446±76 vs. 377±55ms; p<0.001) were greater in patients with DEX, while the HV interval was similar between the groups (42±11 vs. 41±8ms; p=0.63). AF was less often induced in the patients with DEX than in those without (8.3% vs. 20.8%; p=0.01), when a single extra stimulus was given within the atrial vulnerable period.
Conclusions: DEX may have inhibitory effects on both the sinus node and AV node, and may even reduce the AF inducibility in adult AF patients.
Author Disclosures: A. Sairaku: None. Y. Nakano: None. K. Suenari: None. Y. Kihara: None.
- © 2015 by American Heart Association, Inc.