Cardiopulmonary adaptation to short-term high altitude exposure in adult Fontan patients

DOI
Publisher DOI
PubMed ID
27217067
Abstract
OBJECTIVE

High altitude-related hypoxia induces pulmonary vasoconstriction. In Fontan patients without a contractile subpulmonary ventricle, an increase in pulmonary artery pressure is expected to decrease circulatory output and reduce exercise capacity. This study investigates the direct effects of short-term high altitude exposure on pulmonary blood flow (PBF) and exercise capacity in Fontan patients.

METHODS

16 adult Fontan patients (mean age 28±7 years, 56% female) and 14 matched controls underwent cardiopulmonary exercise testing with measurement of PBF with a gas rebreathing system at 540 m (low altitude) and at 3454 m (high altitude) within 12 weeks.

RESULTS

PBF at rest and at exercise was higher in controls than in Fontan patients, both at low and high altitude. PBF increased twofold in Fontan patients and 2.8-fold in the control group during submaximal exercise, with no significant difference between low and high altitude (p=0.290). A reduction in peak oxygen uptake at high compared with low altitude was observed in Fontan patients (22.8±5.1 and 20.5±3.8 mL/min/kg, p<0.001) and the control group (35.0±7.4 and 29.1±6.5 mL/min/kg, p<0.001). The reduction in exercise capacity was less pronounced in Fontan patients compared with controls (9±12% vs 17±8%, p=0.005). No major adverse clinical event was observed.

CONCLUSIONS

Short-term high altitude exposure has no negative impact on PBF and exercise capacity in Fontan patients when compared with controls, and was clinically well tolerated.

TRIAL REGISTRATION NUMBER

NCT02237274: Results.
Date Issued
2016-05-23
Publication Type
Article
Subject(s)
Language(s)
en
Author(s)
Staempfli, Roger
Schmid, Jean-Paul
Schenker, Stephan
Thomet, Corina
Greutmann, Matthias
Tobler, Daniel
Stambach, Dominik
Additional Credits
Journal
Heart
Publisher
BMJ Publishing Group
ISSN
1355-6037
Access(Rights)
restricted
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