Background: The incidence of cardiomyopathy in Duchenne muscular dystrophy (DMD) increases with age, affecting about 90% of patients older than 18. Besides, along with respiratory insufficiency, cardiomyopathy was considered to be responsible for most of the mortality in these individuals. Recent advances in non-invasive ventilator support enabled many DMD patients to live longer, and this have made cardiac issues more crucial. Yet, there is paucity of data dealing with the longitudinal changes of cardiac function and prognosis in late stage DMD patients. Objectives: The purpose of our study was to investigate the prognostic outcome as well as the sequential changes of cardiac function in late stage DMD patients by two-dimensional echocardiography. Methods: A total of 31 individuals (initial age: 21.6짹5.0 years, range: 15-35 years) with late stage DMD were enrolled. Sequential echocardiographic data were collected for at least 3 years. Repeated measures analysis of variance were used to compare changes of left ventricular ejection fraction (LVEF) over time. Results: Overall, sequential change of mean LVEF showed no significant differences with initial, 1-, 2-, and 3-year follow-up LVEF which were 42.2, 42.9, 43.8, and 42.6%, respectively (p=0.320) [Figure 1(a)]. Moreover, there were no significant longitudinal changes of LVEF for each group (p=0.167 and 0.327 for ���no medication��� and ���medication��� group, respectively) [Figure 1(b)]. In terms of prognosis, all but one patient survived during the follow-up period of 46.5 짹 9.1 months. Conclusions: The cardiac function in late stage DMD patients shows stabilization of LVEF under adequate use of ventilatory support and optimal cardiac medication therapy. Furthermore, considering the favorable prognostic outcome in our study, the process of cardiac involvement in late stage DMD may demonstrate non-progressive nature in some patients, implying that cardiac involvement may be unlikely to be the cause of mortality in majority of late stage DMD patients.