Genetic testing and family screening in idiopathic pediatric cardiomyopathy: a prospective observational study from a tertiary care center in North India

Introduction There are limited data on family screening and genetic testing in pediatric cardiomyopathy from India. This study was conducted to describe the morphologic spectrum and identify potential familial and genetic causes of pediatric cardiomyopathies in this region. Methods From April 2018 to May 2020, all children from birth to 18 years of age with cardiomyopathy visiting a tertiary care hospital in North India were enrolled in this study. First-degree relatives of index patients were offered screening for cardiomyopathy; 260 clinically reported pathogenic/likely pathogenic variants in 17 genes were analyzed by a rapid genotyping method. Additionally, a subset of patients also underwent whole-exome sequencing. Results Of the 20 patients enrolled in this study (median age 42 months), 18 were clinically diagnosed with dilated cardiomyopathy. We observed a 44.4% mortality rate after a median follow-up of 15 months. 61.3% of the eligible first-degree relatives underwent screening, and one patient was identified to have familial cardiomyopathy. Multi-panel gene testing was performed on 18 patients, and none were found to have a pathogenic or likely pathogenic variant; 9 patients also underwent whole-exome sequencing, and pathogenic and likely pathogenic variants were identified in 50% (4/8) of them. Conclusion Dilated cardiomyopathy is the most common morphologic form of pediatric cardiomyopathy in India and has a high mortality rate. The prevalence of familial cardiomyopathy was low in this study. Future studies should evaluate the role of whole-exome sequencing in identifying genetic causes of cardiomyopathy in children.