title: Six-Minute Walk Test as a Predictor for Outcome in Children with Dilated Cardiomyopathy and Chronic Stable Heart Failure.
abstract: Cardiopulmonary exercise testing is an important tool to predict prognosis in children and adults with heart failure. A much less sophisticated exercise test is the 6 min walk test, which has been shown an independent predictor for morbidity and mortality in adults with heart failure. Therefore, we hypothesized that the 6 min walk test could be predictive for outcome in children with dilated cardiomyopathy. We prospectively included 49 children with dilated cardiomyopathy ≥6 years who performed a 6 min walk test. Median age was 11.9 years (interquartile range [IQR] 7.4-15.1), median time after diagnosis was 3.6 years (IQR 0.6-7.4). The 6 min walk distance was transformed to a percentage of predicted, using age- and gender-specific norm values (6MWD%). For all patients, mean 6MWD% was 70 ± 21%. Median follow-up was 33 months (IQR 14-50). Ten patients reached the combined endpoint of death or heart transplantation. Using univariable Cox regression, a higher 6MWD% resulted in a lower risk of death or transplantation (hazard ratio 0.95 per percentage increase, p = 0.006). A receiver operating characteristic curve was generated to define the optimal threshold to identify patients at highest risk for an endpoint. Patients with a 6MWD% < 63% had a 2 year transplant-free survival of 73%, in contrast to a transplant-free survival of 92% in patients with a 6MWD% ≥ 63% (p = 0.003). In children with dilated cardiomyopathy, the 6 min walk test is a simple and feasible tool to identify children with a higher risk of death or heart transplantation.
authors.affiliation: Division of Pediatric Cardiology, Sophia Children's Hospital, Erasmus University Medical Center, Dr. Molewaterplein 60, P.O. Box 2060, 3000 CB, Rotterdam, The Netherlands.
authors.forename: Susanna L
authors.initials: SL
authors.lastname: den Boer
authors.affiliation: Division of Pediatric Cardiology, Sophia Children's Hospital, Erasmus University Medical Center, Dr. Molewaterplein 60, P.O. Box 2060, 3000 CB, Rotterdam, The Netherlands.
authors.forename: Daniël H K
authors.initials: DH
authors.lastname: Flipse
authors.affiliation: Division of Pediatric Cardiology, Sophia Children's Hospital, Erasmus University Medical Center, Dr. Molewaterplein 60, P.O. Box 2060, 3000 CB, Rotterdam, The Netherlands.
authors.forename: Marijke H
authors.initials: MH
authors.lastname: van der Meulen
authors.affiliation: Division of Pediatric Cardiology, Emma Children's Hospital, Academic Medical Center, Amsterdam, The Netherlands.
authors.forename: Ad P C M
authors.initials: AP
authors.lastname: Backx
authors.affiliation: Division of Pediatric Cardiology, Beatrix Children's Hospital, University of Groningen, Groningen, The Netherlands.
authors.forename: Gideon J
authors.initials: GJ
authors.lastname: du Marchie Sarvaas
authors.affiliation: Division of Pediatric Cardiology, Department of Pediatrics, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: Arend D J
authors.initials: AD
authors.lastname: Ten Harkel
authors.affiliation: Division of Pediatric Cardiology, Wilhelmina Children's Hospital, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: Gabriëlle G
authors.initials: GG
authors.lastname: van Iperen
authors.affiliation: Division of Pediatric Cardiology, Department of Pediatrics, Free University Medical Center, Amsterdam, The Netherlands.
authors.forename: Lukas A J
authors.initials: LA
authors.lastname: Rammeloo
authors.affiliation: Division of Pediatric Cardiology, Department of Pediatrics, Radboud University Medical Center, Nijmegen, The Netherlands.
authors.forename: Ronald B
authors.initials: RB
authors.lastname: Tanke
authors.affiliation: Division of Pediatric Cardiology, Sophia Children's Hospital, Erasmus University Medical Center, Dr. Molewaterplein 60, P.O. Box 2060, 3000 CB, Rotterdam, The Netherlands.
authors.forename: Willem A
authors.initials: WA
authors.lastname: Helbing
authors.affiliation: Child Development and Exercise Center, Wilhelmina Children's Hospital, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: Tim
authors.initials: T
authors.lastname: Takken
authors.affiliation: Division of Pediatric Cardiology, Sophia Children's Hospital, Erasmus University Medical Center, Dr. Molewaterplein 60, P.O. Box 2060, 3000 CB, Rotterdam, The Netherlands. m.dalinghaus@erasmusmc.nl.
authors.forename: Michiel
authors.initials: M
authors.lastname: Dalinghaus
mesh_terms: D000293:Adolescent; D002311:Cardiomyopathy, Dilated / Q000150:complications*; D002648:Child; D002908:Chronic Disease; D017079:Exercise Tolerance; D005260:Female; D006333:Heart Failure / Q000175:diagnosis* / Q000601:surgery*; D016027:Heart Transplantation; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D009426:Netherlands; D011379:Prognosis; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012372:ROC Curve; D012307:Risk Factors; D000070857:Walk Test
keywords: 6-minute walk test; Dilated cardiomyopathy; Exercise test; Pediatrics; Prognosis