Peak Oxygen Consumption (VO2peak) Recovery Delay in a Pediatric Fontan Population, 2023, Krzywda et al

Abstract
Patients with single ventricle heart disease following Fontan palliation are subject to progressive cardiovascular deterioration during adolescence. In this population, a peak oxygen consumption (VO2peak) less than 50% of predicted is an independent predictor of Fontan related morbidity and mortality. A greater delay in post-exercise VO2 recovery (VO2RD) is associated with worse outcomes in adults with heart failure, however, VO2RD has not been extensively studied in youth with Fontan (single ventricle) physiology.

Purpose
To identify predictors and correlates of VO2RD in youth with Fontan.

Methods
Cardiopulmonary exercise test data was utilized from a single center, cross-sectional study of children and adolescents (age 8-21 years) with Fontan physiology. The VO2RD was determined using time (sec) to <90% of VO2peak and categorized as ‘Low’ (≤10 sec) or ‘High’ (≥10 sec). T-tests and chi-squared analysis were used to compare continuous and categorical variables, respectively.

Results
The analysis sample included n = 30 adolescents with Fontan physiology (age 14.2 ± 2.4; 67% male) with either right ventricular (RV) dominant (40%) or co/left ventricular (Co/LV) dominant (60%) systemic ventricular morphology. There were no differences in VO2peak between the high and low VO2RD groups (High = 1.3 ± 0.4 L/min; Low = 1.3 ± 0.3 L/min; p = 0.97). VO2RD in participants with RV dominance was significantly greater than in patients with Co/LV dominance (RV = 23.8 ± 15.8 sec; Co/LV = 11.8 ± 16.1 sec; p = 0.03).

Conclusions
VO2peak was not correlated with VO2RD when analyzed as high/low VO2RD groups. However, morphology of the systemic single ventricle (RV vs. Co/LV) may be related to rate of recovery in VO2 following a peak cardiopulmonary exercise test.

https://journals.lww.com/acsm-msse/...Consumption__VO2peak__Recovery_Delay.316.aspx