Miyakoshi C, et al. - Whether heart rate (HR) was associated with intravenous immunoglobulin (IVIG) responsiveness or development of coronary artery lesions (CALs) in patients with Kawasaki disease was assessed in this retrospective cohort study. For this investigation, the subjects were divided into 5 groups according to the age- and temperature-adjusted HR z score (HRZage/temp) just before IVIG administration. Findings revealed that HRs had a different relationship with IVIG responsiveness and CALs in patients with Kawasaki disease. Results of this study suggested that low HRZage/temp could be linked with high risk of being refractory to the initial IVIG treatment. On the other hand, the risk of developing CALs increased among those whose HRs were high.