title: Identification of the rate-dependent functional refractory period of the atrioventricular node in simulated atrial fibrillation.
abstract: We continuously observed successive pairs of R-R intervals during atrial fibrillation and hypothesized that the shortest R-R interval for a given preceding R-R interval in a pair represents the functional refractory period of the atrioventricular node at that preceding interval. To test this hypothesis we simulated atrial fibrillation in 28 isolated cross-perfused canine hearts and obtained an R-R interval scatterplot by plotting the R-R intervals as a function of the immediately preceding R-R interval. This scatterplot enabled us to detect a series of the shortest R-R intervals for a wide range of preceding R-R intervals, and this allowed us to estimate the rate-dependent functional refractory period of the atrioventricular node in simulated atrial fibrillation. The estimated functional refractory periods correlated well with those measured by the conventional method (r = 0.93). We conclude that the proposed method makes it possible to estimate the rate-dependent functional refractory periods of the atrioventricular node in atrial fibrillation.
authors.affiliation: Research Institute of Angiocardiology, Cardiovascular Clinic, Kyushu University Medical School, Fukuoka, Japan.
authors.forename: A S
authors.initials: AS
authors.lastname: Chishaki
authors.forename: K
authors.initials: K
authors.lastname: Sunagawa
authors.forename: K
authors.initials: K
authors.lastname: Hayashida
authors.forename: M
authors.initials: M
authors.lastname: Sugimachi
authors.forename: M
authors.initials: M
authors.lastname: Nakamura
mesh_terms: D000818:Animals; D001281:Atrial Fibrillation / Q000503:physiopathology*; D001283:Atrioventricular Node / Q000503:physiopathology*; D002036:Bundle of His / Q000503:physiopathology; D002304:Cardiac Pacing, Artificial; D004285:Dogs; D004562:Electrocardiography; D010477:Perfusion; D012032:Refractory Period, Electrophysiological / Q000502:physiology