title: Exercise induced atrioventricular block with gap phenomenon in atrioventricular conduction.
abstract: A 54-year-old man with normal atrioventricular (AV) conduction at rest gave a 4-year history of presyncope during exercise. Treadmill testing showed exercise induced AV block. Electrophysiological study demonstrated rate dependent infranodal AV block and abnormal refractory period of the His-Purkinje system. The gap phenomenon in AV conduction occurred during the programmed stimulation. Supernormal conduction could be considered as the mechanism of the gap phenomenon in this patient.
authors.affiliation: Department of Cardiology, Niigata City General Hospital, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Toeda
authors.forename: S
authors.initials: S
authors.lastname: Suetake
authors.forename: K
authors.initials: K
authors.lastname: Tsuchida
authors.forename: K
authors.initials: K
authors.lastname: Takahashi
authors.forename: T
authors.initials: T
authors.lastname: Miida
authors.forename: H
authors.initials: H
authors.lastname: Oda
authors.forename: N
authors.initials: N
authors.lastname: Higuma
mesh_terms: D001283:Atrioventricular Node / Q000503:physiopathology*; D002036:Bundle of His / Q000503:physiopathology; D002304:Cardiac Pacing, Artificial; D004562:Electrocardiography; D005080:Exercise Test / Q000009:adverse effects*; D006327:Heart Block / Q000209:etiology* / Q000503:physiopathology / Q000628:therapy; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged