부산대학교 도서관

Introduction: Cardiomyopathy, a well described complication of Duchenne Muscular Dystrophy (DMD), typically presents in adolescence or early adulthood. Transthoracic echocardiography (TTE) is a widely utilized and cost-effective tool to diagnose and monitor its progression. To our knowledge, there is no standardized, echocardiography-based risk stratification to predict progression to DMD cardiomyopathy. We aim to identify markers associated with eventual left ventricular (LV) dysfunction in patients with DMD cardiomyopathy, while they still demonstrate preserved normal LV ejection fraction (LVEF).Methods: We reviewed TTEs of patients with DMD from a single institution and identified their first instance of reduced LVEF (<55%), as well as two preceding TTEs occurring 6-24 months prior. At each time point, we assessed LVEF, LV diastolic parameters, LV global longitudinal strain (LVGLS), LV and atrial volumes. We compared these parameters to 26 age-matched control DMD patients without evidence of LV dysfunction.Results: We identified 28 pediatric DMD patients with LVEF <55%. At each time point preceding reduced LVEF, the average LVGLS and average LVEF were lower, compared to controls. Study patients also demonstrated increased LV end systolic volume, and diminished LVEF and LVGLS over the course of the 3 time points (p<0.05 for all). Logistical regression showed EF and LVGLS one year prior were independently associated with ventricular dysfunction (p = 0.029 and 0.028); age did not correspond with diminished EF.Conclusions: Patients with DMD demonstrate reduced LVGLS, as well as sequentially increasing LV systolic volume and decreasing LVEF prior to the onset of LVEF <55%. These findings suggest a decline in myocardial mechanics >1 year prior to a diagnosis of DMD cardiomyopathy. Recognizing changes in LV strain and volumes while patients are still in a compensated state of cardiac output, may lead to earlier detection of subclinical LV dysfunction.