Effects of persistent Fontan fenestration patency on cardiopulmonary exercise testing variables.

Heal ME, Jackson LB, Atz AM, Butts RJ

Congenit Heart Dis. 2017 Jun 15. doi: 10.1111/chd.12451. [Epub ahead of print]

Cardiopulmonary exercise testing (CPET) aids in clinical assessment of patients
with Fontan circulation. Effects of persistent fenestration on CPET variables
have not been clearly defined. Associations between fenestration and CPET
variables at anaerobic threshold (AT) and peak exercise were explored in the
Pediatric Heart Network Fontan Cross-Sectional Study cohort. Fenestration patency
was associated with a greater decrease in oxygen saturation from rest to peak
exercise (fenestration -4.9 ± 3.8 v. nonfenestration -3 ± 3.5; P < .001).
Physiological dead space at peak exercise was higher in fenestrated v.
nonfenestrated (25.2 ± 16.1 v. 21.4 ± 15.2; P = .03). There was a weak
association between fenestration patency and maximal work and heart rate.
Fenestration patency was also weakly correlated with oxygen pulse, work and
VE/VCO2 at AT. The effect of persistent fenestration on CPET measurements was
minimal in this study, likely due to the cross-sectional design.