Prognostic Value of Cardiopulmonary Exercise Testing in Children With Heart Failure Secondary to Idiopathic Dilated Cardiomyopathy in a Non-Beta-Blocker Therapy Setting

Eur J Heart Fail. 2008 Jun;10(6):560-5. doi: 10.1016/j.ejheart.2008.04.009. Epub 2008 May 16.

Abstract

Background: Peak oxygen consumption and resting left ventricular ejection fraction (LVEF) are independent predictors of survival in adult heart failure (HF) patients.

Aim: To evaluate these factors in children.

Methods: We prospectively studied 31 children with NYHA class I to III HF (mean LVEF 26+/-10%; mean age 8.6+/-1.9 years). All had dilated cardiomyopathy and were awaiting heart transplantation. A cardiopulmonary treadmill exercise test was performed and LVEF determined by radionuclide ventriculography.

Results: During a median follow-up of 1282 days, 20 children reached at least one end-point (death or heart transplantation). Clinical data from the 11 children without events and the 20 children with events are as follows: NYHA class 1+/-0 vs. 2+/-0.9 (p<0.01); SBP 118+/-17 vs. 102+/-16 (p=0.01); DBP 70+/-10 vs. 61+/-10 (p=0.02); heart rate 165+/-22 vs. 148+/-22 (NS); double-product 19+/-4 vs. 15+/-4 (p=0.01); end-tidal carbon dioxide tension (PetCO2) 35+/-5 vs. 30+/-6 (NS); oxygen consumption (VO2) 22+/-5.4 vs. 18.3+/-5.7 (NS); exercise time 19+/-4 vs. 13+/-6 (p<0.003), and LVEF 31+/-8 vs. 22+/-10 (p=0.02). These variables all correlated with prognosis on univariate analysis. In multivariate analysis, only decreasing exercise time and LVEF were predictive of events during follow-up (p<0.001 and 0.04).

Conclusion: These findings suggest that reduction in LVEF and exercise tolerance in children with heart failure is predictive of functional status.

MeSH terms

  • Cardiomyopathy, Dilated / complications*
  • Cardiomyopathy, Dilated / mortality
  • Cardiomyopathy, Dilated / physiopathology
  • Child
  • Cohort Studies
  • Disease-Free Survival
  • Exercise Test*
  • Exercise Tolerance / physiology*
  • Female
  • Heart Failure / etiology
  • Heart Failure / mortality*
  • Heart Failure / physiopathology*
  • Heart Transplantation
  • Humans
  • Male
  • Predictive Value of Tests
  • Rest / physiology
  • Stroke Volume / physiology*
  • Survival Rate