title: Post-ventricular tachycardia P wave change simulating atrial enlargement.
abstract: An abnormal P wave was observed in a child affected by prolonged idiopathic ventricular tachycardia (fascicular tachycardia). After sinus rhythm restoration, the P wave was very tall and peaked (0.5 mV in lead II), suggesting a diagnosis of atrial enlargement. No cardiac abnormality, however, was detected by clinical and echocardiographic examination. The P wave abnormality lasted for about 1 month, with progressive voltage and shape normalization. These P wave changes were probably dependent on tachycardia; since the arrhythmia was long-lasting and characterized by atrioventricular dissociation, repetitive atrial contraction against closed atrioventricular valves caused stretching of atrial fibers, resulting in P wave abnormality. This observation suggests that very prolonged ventricular tachycardia may be associated with an electrocardiographic pattern of pseudoatrial enlargement.
authors.affiliation: Department of Pediatrics, Cardiology Service, University of Messina, Italy.
authors.forename: M P
authors.initials: MP
authors.lastname: Calabrò
authors.forename: G
authors.initials: G
authors.lastname: Oreto
authors.forename: S
authors.initials: S
authors.lastname: Consolo
mesh_terms: D002037:Bundle-Branch Block / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000503:physiopathology; D006332:Cardiomegaly / Q000175:diagnosis*; D002648:Child; D003937:Diagnosis, Differential; D004562:Electrocardiography; D006325:Heart Atria / Q000503:physiopathology; D006801:Humans; D008297:Male; D014463:Ultrasonography