title: Pseudo pre-excitation with concertina effect in idioventricular tachycardia.
abstract: The concertina effect is a phenomenon where the QRS complexes reflect alternating phases of gradual widening and narrowing. This is most commonly due to ventricular pre-excitation, and the changes in QRS morphology are due to variability of the ventricular zone that undergoes pre-excitation. This presentation reflects a case where the concertina effect is due to an idioventricular tachycardia at a rate nearly identical to the sinus rate. Variable degrees of ventricular fusion therefore occur, and the concertina effect ensues, in relation to slight variations of the sinus cycle.
authors.affiliation: Istituto Pluridisciplinare di Clinica Medica, Università di Messina, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Oreto
authors.forename: A
authors.initials: A
authors.lastname: Donato
authors.forename: S
authors.initials: S
authors.lastname: Carerj
mesh_terms: D004562:Electrocardiography; D006352:Heart Ventricles; D006801:Humans; D008297:Male; D008875:Middle Aged; D011226:Pre-Excitation Syndromes / Q000150:complications / Q000503:physiopathology*; D013610:Tachycardia / Q000150:complications / Q000503:physiopathology*