1. Six-minute walking distance and decrease in oxygen saturation during the six-minute walk test in pediatric pulmonary arterial hypertension.
- Author
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Douwes JM, Hegeman AK, van der Krieke MB, Roofthooft MT, Hillege HL, and Berger RM
- Subjects
- Adolescent, Cardiac Catheterization, Child, Exercise Test methods, Familial Primary Pulmonary Hypertension epidemiology, Familial Primary Pulmonary Hypertension metabolism, Female, Follow-Up Studies, Heart Rate physiology, Humans, Incidence, Male, Netherlands epidemiology, Predictive Value of Tests, Prognosis, Severity of Illness Index, Survival Rate trends, Time Factors, Ventricular Function, Right physiology, Exercise Tolerance physiology, Familial Primary Pulmonary Hypertension diagnosis, Oxygen metabolism, Oxygen Consumption, Walking physiology
- Abstract
Objective: To investigate the prognostic value of the 6-minute walking distance (6-MWD), transcutaneous saturation (tcSO2) and heart rate (HR) obtained during the 6-minute walk test (6-MWT) in pediatric pulmonary arterial hypertension (PAH)., Methods: This was an observational study with forty-seven pediatric PAH patients, aged ≥7 years, and diagnosed and followed at the national referral center for pediatric PAH in the Netherlands. All patients performed a comprehensive 6-minute walk test (6-MWT), which measures 6-MWD and tcSO2 and HR before ("baseline"), during ("exercise") and 5 min after ("recovery") the walk test., Results: The 6-MWD expressed either in meters or in sex- and age-corrected z-scores, was associated with transplant-free survival, independently from sex, age, and the presence of a shunt-defect. Shorter 6-MWD correlated with higher WHO-FC and increased NT-pro-BNP. Absolute tcSO2 at exercise and tcSO2-decrease during 6-MWT were associated with transplant-free survival, independent from 6-MWD. Combining tcSO2-decrease with 6-MWD provided the strongest prognostic model. Patients with 6-MWD>352 m (the median 6-MWD) had a better outcome than those with smaller 6-MWD. A large tcSO2-decrease during 6-MWT (>19% for patients with and >5% for patients without a shunt defect) identified patients with worse transplant-free survival both in patients with a 6-MWD above and below the median 6-MWD., Conclusions: The 6-MWD is an independent predictor of prognosis in pediatric PAH, that reflects disease severity and clinically relevant exercise-tolerance and therefore qualifies as a treatment goal. The magnitude of tcSO2-decrease during 6-MWT, adjusted for the presence of a shunt, indicates an additional risk factor for prognosis in children with PAH., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)
- Published
- 2016
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