title: Supraventricular arrhythmia with abnormal QRS complex.
mesh_terms: D001145:Arrhythmias, Cardiac / Q000503:physiopathology*; D002037:Bundle-Branch Block / Q000150:complications; D004562:Electrocardiography; D006329:Heart Conduction System; D006352:Heart Ventricles / Q000503:physiopathology*; D006801:Humans; D013610:Tachycardia / Q000209:etiology