Hereditary cardiomyopathies and arrhythmias are significant components of cardiovascular disease. In recent years, with advances in genomics, researchers have increasingly recognized the associations between these diseases and specific genetic variants. Hereditary cardiomyopathies include various phenotypes, such as hypertrophic cardiomyopathy (HCM), dilated cardiomyopathy (DCM), arrhythmogenic right ventricular cardiomyopathy (ARVC), and left ventricular noncompaction (LVNC). Hereditary arrhythmias include long QT syndrome (LQTS), Brugada syndrome (BrS), catecholaminergic polymorphic ventricular tachycardia (CPVT), and so on. These diseases have complex etiologies involving interactions between multiple genetic variants and environmental factors. Arrhythmias are often the initial symptoms of these cardiomyopathies and can even lead to sudden death (Marian et al., 2020). The application of genetic testing not only facilitates accurate diagnosis but also enables the development of personalized treatment for patients. For example, identifying genetic variants can help assess a patient's genetic risk, allowing for tailored monitoring and intervention strategies (Sun et al., 2020). The emergence of next-generation sequencing (NGS) technologies has enabled the sequencing of an extensive array of genes within a condensed time frame, thereby significantly enhancing testing efficiency and accuracy. Currently, genetic testing relies primarily on multigene panel sequencing and whole-exome sequencing (WES) through NGS (Sun et al., 2020). In addition, as whole-genome sequencing (WGS) becomes more prevalent, genome-wide association studies (GWASs) are increasingly used to identify variants associated with susceptibility to hereditary cardiovascular diseases (Villard et al., 2011; Lahrouchi et al., 2020; Tadros et al., 2021).

These technological advancements have spurred growing interest in the genetic profiles of hereditary cardiomyopathies and arrhythmias in the Chinese population. Although various single-center cohorts in China have explored genetic testing for these diseases, large-scale and multicenter cohort studies that encompass the entire Chinese population are lacking. In this study, we performed a large-scale investigation in China to conduct genetic testing on probands with suspected hereditary cardiomyopathies and arrhythmias from nearly all regions of China. We aimed to reveal the current landscape of genetic variants associated with hereditary cardiomyopathies and arrhythmias in the Chinese population. This study further explored the relationships between these variants and clinical phenotypes, as well as their implications for clinical decision-making, highlighting the geographical distribution patterns of the probands and presenting genetic screening findings for first-degree family members.