title: Arrhythmia and prognosis in infants, children and adolescents with hypertrophic cardiomyopathy.
abstract: In adults with hypertrophic cardiomyopathy, the annual mortality rate from sudden death is 2 to 3%, and the finding of nonsustained ventricular tachycardia during electrocardiographic (ECG) monitoring provides a marker of the patient who is at increased risk. In the young, the annual mortality rate from sudden death is even higher, approximately 6%, but the prognostic significance of arrhythmia is unknown. To determine the prevalence of arrhythmia and its relation to prognosis, 2 days of ECG monitoring was performed in 6 infants, 14 children and 33 adolescents with hypertrophic cardiomyopathy receiving no cardioactive medications. An additional 1 to 9 days (median 2) of monitoring was performed in 29 patients. All patients had sinus rhythm; 4 adolescents had episodes of paroxysmal supraventricular tachycardia, a child with the Wolff-Parkinson-White syndrome had symptomatic reentrant atrioventricular tachycardia and 5 adolescents had asymptomatic nonsustained ventricular tachycardia. During follow-up of 1 week to 7 years (median 3 years), five patients died suddenly and two had successful resuscitation from out-of-hospital ventricular fibrillation; none of these seven patients had ventricular arrhythmias during 2 to 7 days (median 3) of ECG monitoring. The two patients with ventricular fibrillation, the five with ventricular tachycardia, the one with Wolff-Parkinson-White syndrome and the seven with recurrent syncope or adverse family history, or both, received low dose amiodarone. None of these "high risk" patients died during 6 months to 6 years (median 3 years) of follow-up.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Division of Cardiovascular Disease, Hammersmith Hospital, London, England.
authors.forename: W J
authors.initials: WJ
authors.lastname: McKenna
authors.forename: R C
authors.initials: RC
authors.lastname: Franklin
authors.forename: P
authors.initials: P
authors.lastname: Nihoyannopoulos
authors.forename: K C
authors.initials: KC
authors.lastname: Robinson
authors.forename: J E
authors.initials: JE
authors.lastname: Deanfield
mesh_terms: D000293:Adolescent; D001145:Arrhythmias, Cardiac / Q000209:etiology*; D002312:Cardiomyopathy, Hypertrophic / Q000150:complications* / Q000401:mortality; D002648:Child; D002675:Child, Preschool; D003645:Death, Sudden / Q000209:etiology*; D004562:Electrocardiography; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D008991:Monitoring, Physiologic; D011379:Prognosis; D012307:Risk Factors