Prognosis of Right Ventricular Systolic Dysfunction in Patients With Duchenne Muscular Dystrophy

Background Chronic respiratory failure and heart involvement may occur in Duchenne muscular dystrophy. We aimed to assess the prognostic value of the right ventricular (RV) systolic dysfunction in patients with Duchenne muscular dystrophy. Methods and Results We studied 90 genetically proven patients with Duchenne muscular dystrophy from 2010 to 2019, to obtain respiratory function and Doppler echocardiographic RV systolic function. Prognostic value was assessed in terms of death and cardiac events. The median age was 27.5 years, and median forced vital capacity was at 10% of the predicted value: 83 patients (92%) were on home mechanical ventilation. An RV systolic dysfunction was found in 46 patients (51%). In patients without RV dysfunction at inclusion, a left ventricular systolic dysfunction at inclusion was associated with a higher risk of developing RV dysfunction during follow-up with an odds ratio of 4.5 (P=0.03). RV systolic dysfunction was significantly associated with cardiac events, mainly acute heart failure (62%) and cardiogenic shock (23%). In a multivariable Cox model, the adjusted hazard ratio was 4.96 (95% CI [1.09-22.6]; P=0.04). In terms of death, we found a significant difference between patients with RV dysfunction versus patients without RV dysfunction in the Kaplan-Meier curves (log-rank P=0.045). Conclusions RV systolic dysfunction is frequently present in patients with Duchenne muscular dystrophy and is associated with increased risk of cardiac events, irrespective of left ventricular dysfunction and mechanical ventilation. Registration URL: https://www.clinicaltrials.org; unique identifier: NCT02501083.