title: Cardiac conduction and rhythm disturbances following suicidal ingestion of mesoridazine.
abstract: The phenothiazine derivatives, particularly chlorpromazine and thioridazine, are known to produce significant electrocardiographic abnormalities. Until now, documented life-threatening arrhythmias have not been reported following large doses of mesoridazine, the besylate salt of a metabolite of thioridazine and a relatively recent addition to the phenothiazine group. We describe such a case in which alterations in both impulse conduction (first-degree atrioventricular block, prolonged QRS duration, and right axis deviation) and impulse formation (supraventricular and ventricular tachycardia) were noted following a suicidal ingestion of mesoridazine. The electrophysiologic mechanisms underlying phenothiazine-induced arrhythmogenesis are reviewed.
mesh_terms: D000328:Adult; D001145:Arrhythmias, Cardiac / Q000139:chemically induced*; D004562:Electrocardiography; D006329:Heart Conduction System / Q000187:drug effects*; D006801:Humans; D008297:Male; D008653:Mesoridazine / Q000506:poisoning* / Q000627:therapeutic use; D012563:Schizophrenia, Paranoid / Q000188:drug therapy; D013406:Suicide, Attempted
chemical_list: D008653:Mesoridazine