BACKGROUND: Knowledge of the anesthetic effects on atrial and atrioventricular (AV) nodal electrophysiologic properties is fundamental to understand the modulatory role of anesthetics on the pathogenesis of @entity4710 , and to individualize the perioperative management of @entity1 with @entity4710 or AV nodal conduction disturbances. Therefore the authors studied the effects of three commonly used volatile anesthetics on the electrophysiologic properties of the atrium and AV node. METHODS: The concentration-dependent electrophysiologic effects of @entity1508 , @entity5161 , and @entity10233 (0-2 minimum alveolar concentration [MAC]) were studied in @entity840 Langendorff-perfused hearts fit with instruments to simultaneously measure atrial and AV nodal conduction times and atrial monophasic action potential duration. Atrial and AV nodal effective refractory periods were measured simultaneously using a computer-assisted premature stimulation protocol. The concentrations of anesthetics in the gas phase were monitored by an infrared gas analyzer. RESULTS: Volatile anesthetics caused markedly different concentration-dependent effects on atrial conduction, repolarization, and refractoriness, and on AV nodal function. At equianesthetic concentrations, @entity1508 depressed atrial conduction the most, whereas @entity10233 caused the greatest shortening of atrial monophasic action potential duration. @entity1508 had no significant effect on atrial refractoriness, whereas at 2 MAC @entity10233 significantly shortened and @entity5161 significantly prolonged atrial effective refractory periods by 18.1+/-13.5% and 13.2+/-14.7%, respectively. On an equi-MAC basis, the rank order of potency for the anesthetics to prolong AV nodal conduction time and AV nodal ERP was @entity1508 > @entity10233 > @entity5161 . CONCLUSION: The different electrophysiologic effects of volatile anesthetics in the atrium and AV node suggest that these agents may modulate @entity955 in distinctly different ways.

Effects of volatile anesthetics on atrial and AV nodal electrophysiological properties in XXXX isolated perfused heart.

@entity1 :: ('9606', 'Species') :: ['patients'] @entity1508 :: ('MESH:D006221', 'Chemical') :: ['Halothane', 'halothane'] @entity840 :: ('10141', 'Species') :: ['guinea pig'] @entity5161 :: ('MESH:D007530', 'Chemical') :: ['isoflurane'] @entity10233 :: ('MESH:C053562', 'Chemical') :: ['desflurane'] @entity955 :: ('MESH:D001281', 'Disease') :: ['atrial dysrhythmogenesis'] @entity4710 :: ('MESH:D013617', 'Disease') :: ['supraventricular tachycardias']
@entity840 :: (10141,Species) :: ['guinea pig']
