[Right accessory pathway simulating a nodo-ventricular pathway: an electrophysiologic study and intraoperative mapping].
We report a case of a patient with episodes of wide QRS tachycardia and syncope. During the electrophysiologic study, a wide QRS tachycardia (200 b/m) with left bundle branch block morphology was reproducibly induced by incremental atrial pacing with progressive shortening of the HV interval and lengthening of the AV interval, suggesting the presence of a nodoventricular accessory pathway (Mahaim fiber). The intraoperative mapping performed during tachycardia showed the earliest ventricular activation to be over the right antero-lateral AV groove, different from the usual epicardial activation previously described. According to the earliest epicardial breakthrough point, we performed an epicardial AV fat pad dissection which produced irreversible disappearance of preexcitation, confirmed at the postoperative electrophysiologic study. No recurrence of tachycardia was observed during a follow-up of 11 months. This case further confirms previous data that the "so-called" Mahaim fibers could be a right accessory pathway with decremental properties.
Natale
A
A
Istituto di Cardiologia e Cardiochirurgia, Università Cattolica del S. Coure, Roma.
Alessandrini
F
F
Biscione
F
F
Montenero
A S
AS
Pisanò
E
E
Possati
G
G
Santarelli
P
P
D000328:Adult; D004562:Electrocardiography; D004594:Electrophysiology; D006329:Heart Conduction System / Q000503:physiopathology* / Q000601:surgery; D006801:Humans; D008297:Male; D013575:Syncope / Q000209:etiology / Q000503:physiopathology; D013610:Tachycardia / Q000503:physiopathology / Q000601:surgery*
Via accessoria destra che simula una via nodo-ventricolare: studio elettrofisiologico e mappaggio intraoperatorio.