For this study, researchers wanted to determine how the early outbreak of the new Coronavirus Disease 2019 affected the care of patients with congenital cardiac disease. A cohort of surgical patients who had surgery in 2018 (group I), 2019 (group II), and 2020 (group III) and a fellow of follow-up patients who had a follow-up in 2017 (group A), 2018 (group B), and 2019 (group C) in 13 children’s hospitals were enrolled in this study. There was a considerable decline in total surgical volume and a change in case-mix in terms of an increase in the proportion of emergency procedures during the Coronavirus Disease 2019 timeframe. The decrease in migration scale index was linked to lower surgical volume (r=0.64, P=.02) and outpatient visit volume (r=0.61, P=.03). In group C, the proportion of patients who received follow-up through the internet or phone was substantially greater (26.4% vs. 9.6% in group B and 8.9% in group A; P<.0001). There was no statistical difference between the three follow-up groups regarding death or rehospitalization (P =.49). When compared to group B, group C had a higher anxiety score (P<.0001) and used telemedicine more (P=.004). The Coronavirus Disease 2019 pandemic has resulted in a significant reduction in total surgical volume and a shift in case mix, which appears to be linked to the stringent traffic ban. The online medical service appears to be a viable alternative to the traditional manner of follow-up.