School of Medicine, University of Missouri Kansas City, Kansas City, MO, USA.
Division of Health Services & Outcomes Research, Children's Mercy Research Institute, Kansas City, MO, USA.
Cardiol Young. 2023 Nov;33(11):2334-2341. doi: 10.1017/S1047951123000227. Epub 2023 Feb 13.
Many patients with Fontan physiology are unable to achieve the minimum criteria for peak effort during cardiopulmonary exercise testing. The purpose of this study is to determine the influence of physical activity and other clinical predictors related to achieving peak exercise criteria, signified by respiratory exchange ratio ≥ 1.1 in youth with Fontan physiology.
Secondary analysis of a cross-sectional study of 8-18-year-olds with single ventricle post-Fontan palliation who underwent cardiopulmonary exercise testing (James cycle protocol) and completed a past-year physical activity survey. Bivariate associations were assessed by Wilcoxon rank-sum test and simple regression. Conditional inference forest algorithm was used to classify participants achieving respiratory exchange ratio > 1.1 and to predict peak respiratory exchange ratio.
Of the n = 43 participants, 65% were male, mean age was 14.0 ± 2.4 years, and 67.4% (n = 29) achieved respiratory exchange ratio ≥ 1.1. Despite some cardiopulmonary exercise stress test variables achieving statistical significance in bivariate associations with participants achieving respiratory exchange ratio > 1.1, the classification accuracy had area under the precision recall curve of 0.55. All variables together explained 21.4% of the variance in respiratory exchange ratio, with peak oxygen pulse being the most informative.
Demographic, physical activity, and cardiopulmonary exercise test measures could not classify meeting peak exercise criteria (respiratory exchange ratio ≥ 1.1) at a satisfactory accuracy. Correlations between respiratory exchange ratio and oxygen pulse suggest the augmentation of stroke volume with exercise may affect the Fontan patient's ability to sustain high-intensity exercise.
许多 Fontan 生理患者无法达到心肺运动测试中最大努力的最低标准。本研究的目的是确定体力活动和其他与达到峰值运动标准相关的临床预测因素（呼吸交换率≥1.1）对 Fontan 生理青少年的影响。
对接受心肺运动测试（James 循环方案）并完成过去一年体力活动调查的单心室 Fontan 姑息术后 8-18 岁青少年的横断面研究进行二次分析。采用 Wilcoxon 秩和检验和简单回归评估双变量相关性。使用条件推断森林算法对达到呼吸交换率>1.1的参与者进行分类，并预测峰值呼吸交换率。
在 n=43 名参与者中，65%为男性，平均年龄为 14.0±2.4 岁，67.4%（n=29）达到呼吸交换率≥1.1。尽管一些心肺运动压力测试变量在与达到呼吸交换率>1.1的参与者的双变量相关性中达到统计学意义，但分类准确性的精度召回曲线下面积为 0.55。所有变量共同解释了呼吸交换率方差的 21.4%，其中峰值氧脉搏是最具信息量的变量。
人口统计学、体力活动和心肺运动测试措施无法以令人满意的准确性对达到峰值运动标准（呼吸交换率≥1.1）进行分类。呼吸交换率与氧脉搏之间的相关性表明，随着运动的增加，每搏输出量的增加可能会影响 Fontan 患者维持高强度运动的能力。
