title: Left-sided intraventricular conduction delay concealed by right bundle branch block.
abstract: The electrocardiograms of a 69-year-old woman with severe heart failure showed a left-sided nonspecific intraventricular conduction delay (QRS duration, 0.13 seconds) characterized by notches and slurrings in the descending part of the R waves in the left precordial leads and in the ascending parts of the S waves in the right precordial leads. Subsequently, a complete right bundle branch block with wider QRS complexes (0.17 seconds) appeared. It is possible to consider that the left-sided nonspecific intraventricular conduction delay was concealed by the greater conduction delay occurring when the complete right bundle branch block was present. This would be in keeping with a previous study using Doppler tissue imaging in which this was postulated but where the corresponding electrocardiograms were not shown.
authors.affiliation: Division of Cardiology, Department of Medicine of the University of Miami Miller School of Medicine, Miami, FL, USA. acastell@med.miami.edu
authors.forename: Agustin
authors.initials: A
authors.lastname: Castellanos
authors.forename: Freddy del Carpio
authors.initials: Fdel C
authors.lastname: Munoz
authors.forename: Jose A
authors.initials: JA
authors.lastname: Martel
mesh_terms: D000368:Aged; D001145:Arrhythmias, Cardiac / Q000150:complications* / Q000175:diagnosis*; D002037:Bundle-Branch Block / Q000150:complications* / Q000175:diagnosis*; D003937:Diagnosis, Differential; D004562:Electrocardiography; D005260:Female; D006801:Humans; D018487:Ventricular Dysfunction, Left / Q000150:complications* / Q000175:diagnosis*