title: [Ventricular pre-excitation disclosed by an episode of high-frequency atrial fibrillation: the role of frequency-dependent variations in the bundle of Kent conduction].
abstract: The presence of a ventricular pre-excitation, which becomes evident only during episodes of atrial fibrillation, is a very rare event. The authors report a case of ventricular pre-excitation revealed by an access of atrial fibrillation with high ventricular frequency and hemodynamic failure. The ventricular pre-excitation signs were not evident after the sinus rythm had been restored. The electrophysiological study has shown that such behaviour is not related to a different input of the stimulus in the bypass tract during the passage from the sinus rhythm to the atrial fibrillation, as other authors have recently suggested, but to rate-dependent variations of the conduction in the Kent bundle: in the bypass either a phase-4 block of the conduction is present, or a supernormal conduction.
authors.affiliation: Divisione di Cardiologia, Ospedale Civile, Centro, Ferrara.
authors.forename: N
authors.initials: N
authors.lastname: Paparella
authors.forename: R
authors.initials: R
authors.lastname: Mureddu
authors.forename: G
authors.initials: G
authors.lastname: Musso
authors.forename: M
authors.initials: M
authors.lastname: De Thomatis
mesh_terms: D001281:Atrial Fibrillation / Q000150:complications / Q000503:physiopathology*; D004562:Electrocardiography; D006329:Heart Conduction System / Q000503:physiopathology*; D006801:Humans; D008875:Middle Aged; D011226:Pre-Excitation Syndromes / Q000150:complications / Q000503:physiopathology*
vernacular_title: Preeccitazione ventricolare svelata da un accesso di fibrillazione atriale ad alta frequenza: ruolo delle variazioni frequenza-dipendenti della conduzione nel fascio di Kent.