title: Ventricular rhythm obscuring the diagnosis of ostium primum atrial septum defect.
abstract: A 13 year old boy with an ostium primum atrial septal defect associated with alternating periods of sinus rhythm and ventricular rhythm is presented. Absence of auscultatory and phonocardiographic signs of an atrial septal defect made it impossible to diagnose the defect correctly during periods of ventricular rhythm.
mesh_terms: D000293:Adolescent; D001145:Arrhythmias, Cardiac / Q000209:etiology*; D004562:Electrocardiography; D006344:Heart Septal Defects, Atrial / Q000150:complications / Q000175:diagnosis*; D006801:Humans; D008297:Male; D010701:Phonocardiography