Genetic testing identified pathogenic variants in 86.5% of pediatric cardiomyopathy cases and those with positive results had 2.87-fold higher survival (P < 0.001).
In a nationwide South Korean cohort of paediatric cardiomyopathy, genetic testing identified pathogenic variants in 86.5% of tested cases, and a positive genetic result was associated with a significantly higher likelihood of survival.
Abstract Background/Introduction Paediatric cardiomyopathy is a significant cause of morbidity and mortality in children. Despite extensive global research, comprehensive epidemiological data from Korea - particularly on hereditary forms - remain limited. Purpose This study aimed to elucidate the clinical spectrum, genetic characteristics, and outcomes in a nationwide cohort of paediatric patients with cardiomyopathy in South Korea. Methods A retrospective cohort study was conducted on paediatric patients diagnosed with cardiomyopathy in South Korea. Patients aged 18 years or younger, diagnosed between January 2000 and May 2022, were included. Data were retrospectively collected from June 2022 to December 2024 from 21 participating centres across South Korea. A total of 1227 patients were enrolled (from an initial 1289 cases), with duplicate entries removed by retaining only the last follow-up record or those from the hospital primarily responsible for patient management. Results The cohort demonstrated a male predominance (800, 65.2%) and a mean age at diagnosis of 7.8 ± 6.6 years (range: 0–18 years). Cardiomyopathy was classified as dilated cardiomyopathy (DCM, 63.4%), hypertrophic cardiomyopathy (HCM, 27.6%), restrictive cardiomyopathy (RCM, 3.6%), left ventricular non-compaction (LVNC, 4.2%), and arrhythmogenic right ventricular dysplasia (ARVD, 1.2%). Cases with mixed phenotypes (n=42) were integrated into the primary diagnostic categories. In 34% of patients, cardiomyopathy was incidentally discovered during examinations for cardiac murmurs or other medical conditions. Among those presenting with symptoms at diagnosis, cardiac symptoms were observed in only 17.2% of patients, while respiratory symptoms were present in 31.1%, gastrointestinal symptoms in 25.1%, and other non-specific generalized symptoms in 26.6%. Genetic testing was performed in 694 patients (56.6%) using various modalities and identified pathogenic or likely pathogenic variants in 86.5% of cases. Distinct clinical and genetic profiles were observed across subtypes, with the highest rates of positive genetic testing seen in DCM and HCM (Figure 1). Patients with positive genetic result had a 2.876-fold higher likelihood of survival compared to those without (P 0.001). Overall, the cohort exhibited a survival rate of 61%, with transplantation, mortality, and loss to follow-up rates of 11%, 15%, and 13%, respectively, with significant variation in outcomes across different subtypes (Figure 2). Conclusion This nationwide study highlights the heterogeneity of paediatric cardiomyopathy in South Korea and underscores the critical role of genetic evaluation in optimising clinical management. These findings may contribute to enhanced risk stratification and the development of tailored therapeutic strategies for affected children.Genetic test results Overall outcomes
Kwon et al. (2025) studied this question. Genetic testing identified pathogenic variants in 86.5% of pediatric cardiomyopathy cases and those with positive results had 2.87-fold higher survival (P < 0.001).