Background The majority of people born with congenital heart disease require lifelong cardiac follow‐up. However, discontinuity of care is a recognized problem and appears to increase around the transition to adulthood. We performed a systematic review and meta‐analysis to estimate the proportion of adolescents and emerging adults with congenital heart disease discontinuing cardiac follow‐up. In pooled data, we investigated regional differences, disparities by disease complexity, and the impact of transition programs on the discontinuity of care. Methods and Results Searches were performed in PubMed, Embase, Cinahl, and Web of Science. We identified 17 studies, which enrolled 6847 patients. A random effects meta‐analysis of single proportions was performed according to the DerSimonian‐Laird method. Moderator effects were computed to explore sources for heterogeneity. Discontinuity proportions ranged from 3.6% to 62.7%, with a pooled estimated proportion of 26.1% (95% CI, 19.2%–34.6%). A trend toward more discontinuity was observed in simple heart defects (33.7%; 95% CI, 15.6%–58.3%), compared with moderate (25.7%; 95% CI, 15.2%–40.1%) or complex congenital heart disease (22.3%; 95% CI, 16.5%–29.4%) ( P =0.2372). Studies from the United States (34.0%; 95% CI, 24.3%–45.4%), Canada (25.7%; 95% CI, 17.0%–36.7%), and Europe (6.5%; 95% CI, 5.3%–7.9%) differed significantly ( P =0.0004). Transition programs were shown to have the potential to reduce discontinuity of care (12.7%; 95% CI, 2.8%–42.3%) compared with usual care (36.2%; 95% CI, 22.8%–52.2%) ( P =0.1119). Conclusions This meta‐analysis showed that there is a high proportion of discontinuity of care in young people with congenital heart disease. The highest discontinuity proportions were observed in studies from the United States and in patients with simple heart defects. It is suggested that transition programs have a protective effect. Registration URL: www.crd.york.ac.uk/prospero . Unique identifier: CRD42020182413.

Background: Providing continuous follow-up care to patients with congenital heart disease (CHD) remains a challenge in many settings. Previous studies highlight that patients with CHD experience discontinuation of followup care, but mainly describe a single-centre perspective, neglecting inter-institutional variations. Hospitalrelated factors above and beyond patient-related factors are believed to affect continuity of care. The present multicentre study therefore investigated (i) proportion of "no follow-up care"; (ii) transfer destinations after leaving paediatric cardiology; (iii) variation in proportions of no follow-up between centres; (iv) the association between no follow-up and outpatient volumes, and (v) its relationship with staffing resources at outpatient clinics. Methods: An observational, multicentre study was conducted in seven university hospitals. In total, 654 adolescents with CHD, born between 1991 and 1993, with paediatric outpatient visit at age 14-18 years were included. Transfer status was determined 5 years after the intended transfer to adult care (23y), based on medical files, selfreports and registries. Results: Overall, 89.7% of patients were receiving adult follow-up care after transfer; 6.6% had no follow-up; and 3.7% were untraceable. Among patients in follow-up care, only one remained in paediatric care and the majority received specialist adult CHD care. Significant variability in proportions of no follow-up were identified across