title: Hemodynamic and electrophysiologic evaluation of patients with hypertrophic cardiomyopathy surviving cardiac arrest.
abstract: Hemodynamic and electrophysiologic studies were performed in 30 survivors of sudden cardiac arrest with hypertrophic cardiomyopathy (HC) to determine responsible factors. Electrophysiologic abnormalities alone were present in 27 patients (90%): sinus node dysfunction in 14 (47%), delayed atrio-ventricular nodal conduction in 1 (3%), abnormal His-Purkinje conduction in 7 (23%), an inducible atrial tachycardia in 7 (23%), and inducible sustained ventricular arrhythmia in 21 (70%). Sustained ventricular arrhythmia was polymorphic ventricular tachycardia (VT) in 18 patients (86%), monomorphic VT in 2 patients (7%) and ventricular fibrillation in 1 patient (3%). In 1 patient the arrhythmia recorded during an episode of cardiac arrest and induced at electrophysiologic study was polymorphic VT. VT was induced with less than or equal to 2 extra-stimuli in only 1 patient (3%) but with less than or equal to 3 extra-stimuli in 20 patients (97%). Potential causes of sudden cardiac arrest were found in all patients and were multiple in 13 patients (43%). These were (1) ventricular electrical instability in 21 patients (70%), (2) severe left ventricular outflow tract obstruction in 8 patients (27%), (3) bradycardia in 5 patients (17%), (4) myocardial ischemia associated with hypotension in 5 patients (17%), and (5) atrial tachycardia resulting in hypotension in 4 patients (13%). Of the 21 patients with inducible sustained ventricular arrhythmia, 17 received an implantable defibrillator device and 4 were treated with antiarrhythmic drugs. Seven patients underwent left ventricular septal myectomy.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Cardiovascular Diagnosis Section, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland 20892.
authors.forename: L
authors.initials: L
authors.lastname: Fananapazir
authors.forename: S E
authors.initials: SE
authors.lastname: Epstein
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D001145:Arrhythmias, Cardiac / Q000150:complications / Q000503:physiopathology; D002312:Cardiomyopathy, Hypertrophic / Q000150:complications* / Q000503:physiopathology*; D015716:Electrocardiography, Ambulatory; D004594:Electrophysiology; D005260:Female; D006323:Heart Arrest / Q000209:etiology* / Q000401:mortality / Q000503:physiopathology* / Q000628:therapy; D006439:Hemodynamics / Q000502:physiology*; D006801:Humans; D007022:Hypotension / Q000150:complications / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D015996:Survival Rate; D014694:Ventricular Outflow Obstruction / Q000150:complications / Q000503:physiopathology