[Application and clinical value of cardiopulmonary exercise test in children with Kawasaki disease sequelae of giant coronary artery aneurysm].

Objective: To investigate the changes and significance of cardiopulmonary adaptations in children with Kawasaki disease sequelae of giant coronary artery aneurysm (KD-GCAA). Methods: A retrospective cohort study. Twenty-nine KD-GCAA children diagnosed at the Children's Hospital of Fudan University from January 2024 to March 2025 were enrolled as GCAA group, and 67 healthy children matched in age, gender and body mass index during the same period were selected as control group. The GCAA group underwent cardiopulmonary exercise test (CPET) after completing a questionnaire-based assessment, while the control group underwent CPET directly. Wilcoxon signed-rank test was used to compare the differences in daily activity and actual exercise capacity of children in the GCAA group, as well as differences in CPET-related indicators and treadmill exercise test (TET) related indicators. Independent sample t-test and Mann-Whitney U test were used to compare the differences in CPET indicators between the GCAA group and control group. Results: The GCAA group consisted of 20 males and 9 females, with the age of (10.9±2.2) years, while the control group included 45 males and 22 females, with the age of (11.1±2.1) years. Daily activity metabolic equivalent of task (MET) was 4.5 (4.5,5.0) in KD-GCAA group which was significantly lower than the maximum MET 10.8 (9.9,12.1) and MET at the anaerobic threshold 8.0 (7.1,8.9) measured by CPET (both P<0.001). All children completed the modified Bruce protocol up to stage 5-6 without adverse events. Decreased exercise tolerance was observed in 10% (3/29) of the GCAA group, all of which were missed by TET. Peak oxygen uptake per kilogram of body mass (peak V'O2/kg), peak V'O2/kg to predicted value, maximum MET, V'O2/kg at anaerobic threshold, V'O2/kg at anaerobic threshold to predicted value,MET at anaerobic threshold, heart rate at anaerobic threshold, maximum minute ventilation and ventilatory equivalent for carbon dioxide were significantly lower than those in the control group (all P<0.05). The maximum MET measured by TET was significantly higher than that by CPET in GCAA group (11.5 (10.2, 13.2) vs. 10.8 (9.9, 12.1), Z=2.24,P=0.025). Conclusions: KD-GCAA children have lower cardiopulmonary fitness and exercise tolerance than healthy children, along with insufficient daily physical activity. Compared with TET, CPET can more accurately evaluate the changes in cardiopulmonary fitness of these children, which holds important application value for clinical exercise guidance.