title: Bradycardia- and tachycardia-dependent termination of ventricular bigeminy: mechanism of ventricular extrasystoles with fixed coupling.
abstract: Fourteen men with intermittent ventricular bigeminy were selected for this study because coupling intervals of the extrasystoles were considerably long and usually fixed, and bradycardia-dependent (10 cases) and/or tachycardia-dependent (12 cases) termination of bigeminy occurred. In all cases, when the heart rate ranged between two certain values, ventricular bigeminy with fixed-coupled extrasystoles was sustained. In all cases showing bradycardia-dependent termination, bigeminy was suddenly terminated with no changes in coupling of the preceding extrasystoles when the heart rate was decreased below a certain lower value. In all cases showing tachycardia-dependent termination except one, when the heart rate increased beyond a certain higher value, coupling intervals gradually lengthened until bigeminy was terminated. These findings strongly suggest the possibility that, in a considerably large number of clinical cases, ventricular extrasystoles with fixed coupling are caused by longitudinal dissociation of conduction in the reentrant pathway of extrasystoles.
authors.affiliation: Health Administration Center, Hokkaido University, Sapporo, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Kinoshita
authors.forename: F
authors.initials: F
authors.lastname: Okada
authors.forename: G
authors.initials: G
authors.lastname: Konishi
authors.forename: M
authors.initials: M
authors.lastname: Kinoshita
authors.forename: S
authors.initials: S
authors.lastname: Ogawa
mesh_terms: D000328:Adult; D001283:Atrioventricular Node / Q000503:physiopathology; D001919:Bradycardia / Q000503:physiopathology; D005117:Cardiac Complexes, Premature / Q000503:physiopathology*; D004562:Electrocardiography; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D017180:Tachycardia, Ventricular / Q000503:physiopathology*