Incidence of and risk factors for sudden cardiac death in children with dilated cardiomyopathy: a report from the Pediatric Cardiomyopathy Registry.
OBJECTIVE
The purpose of this study was to establish the incidence of and risk factors for sudden cardiac death (SCD) in pediatric dilated cardiomyopathy (DCM).


BACKGROUND
The incidence of SCD in children with DCM is unknown. The ability to predict patients at high risk of SCD will help to define who may benefit most from implantable cardioverter-defibrillators.


METHODS
The cohort was 1,803 children in the PCMR (Pediatric Cardiomyopathy Registry) with a diagnosis of DCM from 1990 to 2009. Cumulative incidence competing-risks event rates were estimated. We achieved risk stratification using Classification and Regression Tree methodology.


RESULTS
The 5-year incidence rates were 29% for heart transplantation, 12.1% non-SCD, 4.0% death from unknown cause, and 2.4% for SCD. Of 280 deaths, 35 were SCD, and the cause was unknown for 56. The 5-year incidence rate for SCD incorporating a subset of the unknown deaths is 3%. Patients receiving antiarrhythmic medication were at higher risk of SCD (hazard ratio: 3.0, 95% confidence interval: 1.1 to 8.3, p = 0.025). A risk stratification model based on most recent echocardiographic values had 86% sensitivity and 57% specificity. Thirty of 35 SCDs occurred in patients who met all these criteria: left ventricular (LV) end-systolic dimension z-score >2.6, age at diagnosis younger than 14.3 years, and the LV posterior wall thickness to end-diastolic dimension ratio <0.14. Sex, ethnicity, cause of DCM, and family history were not associated with SCD.


CONCLUSIONS
The 5-year incidence rate of SCD in children with DCM is 3%. A risk stratification rule (86% sensitivity) included age at diagnosis younger than 14.3 years, LV dilation, and LV posterior wall thinning. Patients who consistently meet these criteria should be considered for implantable cardioverter-defibrillator placement.
Children's Memorial Hospital, Northwestern University, Chicago, IL 60614, USA. epahl@childrensmemorial.org
Elfriede
E
Pahl
Lynn A
LA
Sleeper
Charles E
CE
Canter
Daphne T
DT
Hsu
Minmin
M
Lu
Steven A
SA
Webber
Steven D
SD
Colan
Paul F
PF
Kantor
Melanie D
MD
Everitt
Jeffrey A
JA
Towbin
John L
JL
Jefferies
Beth D
BD
Kaufman
James D
JD
Wilkinson
Steven E
SE
Lipshultz
D000293:Adolescent; D002311:Cardiomyopathy, Dilated / Q000150:complications* / Q000175:diagnosis / Q000401:mortality; D002648:Child; D002675:Child, Preschool; D016757:Death, Sudden, Cardiac / Q000453:epidemiology* / Q000209:etiology; D004452:Echocardiography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D007223:Infant; D008297:Male; D012042:Registries; D012189:Retrospective Studies; D012307:Risk Factors; D015996:Survival Rate / Q000639:trends; D013997:Time Factors; D014481:United States / Q000453:epidemiology