Background: Cardiovascular sequelae after Kawasaki disease (KD) are typically linked to coronary artery aneurysms. This post-hoc analysis describes response to exercise challenge late after KD to determine response according to coronary artery status. Methods: Bruce treadmill testing was performed under an international trail in 117 KD without coronary complications (NS-KD) and 133 with coronary artery aneurysm (CAA-KD). Endurance time, heart rate, systolic and diastolic blood pressure were assessed at rest, at each treadmill stage, peak exercise and recovery. The presence of myocardial perfusion defects was assessed by Tc-99m sestamibi SPECT imaging. Results: Endurance time was similar between groups (11.3 ± 2.6 min vs11.0 ± 2.6 min, NS-KD vs CAA-KD; p=0.343). There were similar responses in all investigated parameters as well (table 1) (p=0.075-0.942). The prevalence of myocardial perfusion defects was comparable in both groups (22.2% in NS-KD and 16.5% in CAA-KD; p=0.255), but predicted lower heart rate at 1-min recovery as well as lower diastolic blood pressure at 1-min and 5-min recovery in patients with abnormal Summed Stress Score > 3 (p = 0.017-0.042).; reversible defects in 12.8% of NS-KD and 11.3% of CAA-KD (p=0.708). Conclusion: Compared to KD patients without CA involvement, the presence of coronary aneurysms at the sub-acute phase does not induce a differential effect on exercise parameters. In contrast, exercise induced myocardial perfusion defect late after the onset of KD correlates with abnormal recovery parameters. These data suggest that the exercise performance alone is unlikely to discriminate patients with or without coronary artery sequelae.