title: The long QT syndrome: a prospective international study.
abstract: During the past 4 years 196 patients with the idiopathic long QT syndrome were enrolled in a prospective international study conducted to obtain a better understanding of the clinical course of this unusual repolarization disorder. The mean patient age was 24 years, 64% were female, and 88% had family members with QT prolongation. During an average follow-up of 26 months per patient, four patients died suddenly (1.3% per year) and 27 patients had one or more syncopal episodes (8.6% per year). Multivariate analysis identified congenital deafness, history of syncope, female gender, and a documented episode of torsades de pointes or ventricular fibrillation as independent risk factors for postenrollment syncope or sudden death. Two types of treatment (left stellate ganglionectomy and beta-blocker therapy) were associated with a significant reduction in the occurrence of cardiac events during follow-up.
authors.forename: A J
authors.initials: AJ
authors.lastname: Moss
authors.forename: P J
authors.initials: PJ
authors.lastname: Schwartz
authors.forename: R S
authors.initials: RS
authors.lastname: Crampton
authors.forename: E
authors.initials: E
authors.lastname: Locati
authors.forename: E
authors.initials: E
authors.lastname: Carleen
mesh_terms: D000293:Adolescent; D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use; D000328:Adult; D000704:Analysis of Variance; D001145:Arrhythmias, Cardiac / Q000401:mortality / Q000503:physiopathology* / Q000628:therapy; D002648:Child; D003638:Deafness / Q000151:congenital; D003645:Death, Sudden / Q000209:etiology; D004562:Electrocardiography; D005260:Female; D006801:Humans; D007391:International Cooperation; D008297:Male; D011446:Prospective Studies; D012042:Registries; D012737:Sex Factors; D013562:Sympathectomy; D013575:Syncope / Q000503:physiopathology; D013577:Syndrome; D013610:Tachycardia / Q000503:physiopathology; D014693:Ventricular Fibrillation / Q000503:physiopathology
chemical_list: D000319:Adrenergic beta-Antagonists