title: His bundle extrasystoles revisited: the great electrocardiographic masquerader.
abstract: A 74-year-old man with past history of near syncope presented with frequent periods of second-degree atrioventricular block (2° AVB). An electrophysiological study revealed prolonged atrial-His and His-ventricular (HV) intervals and frequent His bundle (H) extrasystoles. The latter manifested in the surface electrocardiogram as premature atrial, junctional, or ventricular beats, as well as 2° AVB that mimicked Wenckebach or Mobitz II block. Procainamide markedly suppressed H extrasystole. However, because of the presence of prolonged HV interval and history of presyncope, a permanent pacemaker was inserted. The case illustrates the varied manifestation of H extrasystole and presents guidelines for management.
authors.affiliation: New York Harbor VA Healthcare Center, State University of New York Downstate Medical Center, Brooklyn, NY 11209, USA.
authors.forename: Abdul
authors.initials: A
authors.lastname: Ameen
authors.forename: Amita
authors.initials: A
authors.lastname: Dharawat
authors.forename: Abdullah
authors.initials: A
authors.lastname: Khan
authors.forename: Gioia
authors.initials: G
authors.lastname: Turitto
authors.forename: Nabil
authors.initials: N
authors.lastname: El-Sherif
mesh_terms: D000368:Aged; D002036:Bundle of His / Q000503:physiopathology*; D003937:Diagnosis, Differential; D004562:Electrocardiography / Q000379:methods*; D006801:Humans; D008297:Male; D018879:Ventricular Premature Complexes / Q000175:diagnosis* / Q000503:physiopathology*