Investigation of cardiac natural course in pediatric dystrophinopathy patients

. Dystrophin-related muscular dystrophies include a spectrum of X-linked muscle diseases resulting from mutations in the dystrophin gene and inherited recessively,. This study investigates the cardiac clinical characteristics and age-grouped cardiac findings in pediatric dystrophinopathy patients, particularly Duchenne (DMD) and Becker muscular dystrophy (BMD). The study also aims to identify the relationships between clinical findings across different organ systems. A retrospective cross-sectional study was conducted on 86 DMD and 17 BMD patients followed at a single tertiary center. Clinical data, including ambulation status, genetic mutation results, echocardiography, electrocardiography (ECG), Holter monitoring, cardiac magnetic resonance imaging (CMR), pulmonary function tests, and polysomnography were analyzed. The mean age of DMD patients was 12.2 years (range: 3–18 years) and 15.2 years (range: 8–18 years) in BMD patients. Left ventricular dysfunction was observed in 47.1% of BMD patients, significantly higher than the 23.5% observed in DMD patients (p=0.072). In DMD patients, elevated late gadolinium enhancement scores on CMR were associated with reduced heart rate variability and increased sinus tachycardia, particularly in older age groups. Restrictive pulmonary patterns and nocturnal hypoventilation were more prevalent in DMD patients over the age of 10 years. These pulmonary complications correlated with right bundle branch block and right ventricular hypertrophy on ECG. The median age of ambulation loss in DMD patients was 13 years, coinciding with an increased prevalence of cardiac dysfunction and pulmonary complications. BMD patients, despite a later onset of symptoms, exhibited more pronounced cardiac abnormalities by their mid-teens. The findings underscore the importance of age-specific monitoring in DMD and BMD patients. Early detection of cardiac and pulmonary complications, particularly in the pre-symptomatic stages, can facilitate timely intervention. In DMD patients, the interplay between pulmonary complications and cardiac dysfunction highlights the importance of integrated care. HRV is valuable for identifying subclinical cardiac dysfunction and guiding early interventions. This study emphasizes adherence to updated treatment and monitoring protocols for managing dystrophinopathies' cardiac complications. The higher prevalence of left ventricular dysfunction in BMD patients compared to DMD patients, despite their typically milder disease course, challenges prevailing assumptions. Identifying gaps in beta-blocker and MRA use for these patients is significant, as it calls attention to potential areas for improving adherence to guidelines and optimizing therapeutic approaches. Regular assessment and early interventions targeting cardiac and pulmonary health can significantly enhance affected individuals' quality and longevity of life.