Cardiac characteristics of Chinese patients with Danon disease associated with

Background: This study characterized the clinical and genetic features of Danon disease (DD), focusing on participants harboring Methods: We conducted a retrospective analysis of nine patients with DD diagnosed at the Fuwai Hospital of the Chinese Academy of Medical Sciences, Beijing, China. Comprehensive clinical data, including biochemical markers, electrocardiographic findings, and imaging studies (echocardiography and cardiac magnetic resonance imaging), were collected. Pathogenic Results: All participants carried pathogenic frameshift variants at p.Leu325fs, presenting with prominent cardiac manifestations including myocardial hypertrophy or dilation, impaired systolic function, and arrhythmias. Electrocardiographic abnormalities, notably intraventricular conduction block and ST-T segment changes, were observed in all participants. Elevated N-terminal prohormone of brain natriuretic peptide and lactate dehydrogenase levels were observed in all participants, consistent with advanced heart failure and myocardial injury. Conclusions: Our findings suggest that p.Leu325fs pathogenic variants in DD are associated with a predominantly cardiac phenotype, characterized by universal intraventricular conduction block, ST-T segment changes, progressive myocardial fibrosis, and impaired systolic function. These results support the clinical value of integrating