title: The role of electrophysiologic studies in the management of patients with unexplained syncope.
abstract: We evaluated the frequency and type of electrophysiologic abnormalities in an unselected population of consecutive patients with unexplained syncope. Fifty patients were entered in the study; all had 24-hour dynamic electrocardiographic (Holter) recordings and underwent complete electrophysiological studies. An abnormal electrophysiologic study was found in 74% of the patients. Sinus node abnormality was observed in 30%, abnormal AV node function in 14%, long HV in 10%, block distal to H during rapid atrial pacing in 6%, paroxysmal supraventricular tachycardia in 12%, ventricular tachycardia/fibrillation in 8%, and hypersensitive carotid sinus syndrome in 24%. There was no correlation between Holter and electrophysiologic study findings except for the presence of paroxysmal sustained supraventricular tachycardia. Based on clinical, Holter monitoring, and electrophysiologic findings, 38% were treated by antiarrhythmic drugs, 40% received permanent pacemakers, and 22% were not treated at all. During follow-up (23 +/- 13 months), 9 patients (18%) experienced recurrent syncope or death.
authors.forename: P
authors.initials: P
authors.lastname: Denes
authors.forename: M D
authors.initials: MD
authors.lastname: Ezri
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use; D001145:Arrhythmias, Cardiac / Q000503:physiopathology* / Q000628:therapy; D002346:Carotid Sinus / Q000294:innervation; D003131:Combined Modality Therapy; D004452:Echocardiography; D004562:Electrocardiography; D005080:Exercise Test; D005260:Female; D005500:Follow-Up Studies; D006329:Heart Conduction System / Q000503:physiopathology; D006331:Heart Diseases / Q000150:complications; D006801:Humans; D008297:Male; D008875:Middle Aged; D010138:Pacemaker, Artificial; D013575:Syncope / Q000503:physiopathology* / Q000517:prevention & control
chemical_list: D000889:Anti-Arrhythmia Agents