Abstract 13168: Abnormal Circumferential Strain Is Present in Young Duchenne Muscular Dystrophy Patients
Background Advances in management of Duchenne muscular dystrophy (DMD) have improved such that DMD-associated cardiac disease has become the leading cause of death. Cardiac function as measured by standard transthoracic echocardiogram (TTE) methods, e.g. fractional shortening (FS), rarely detects global dysfunction during the first decade. In the current study we used TTE to assess strain (ε), both segmentally and globally, in young DMD patients.
Methods TTE from DMD patients ≤8 years (n=63) recorded during 2009-2010 were compared to TTE of an age-matched control group with no cardiovascular disease (n=61). Feature tracking analysis software (Image Arena, TomTec, Germany) was used to measure global circumferential strain (εcc) and segmental εcc based on a modified AHA/ASE 16-segment model.
Results While there were no differences in FS between groups, the global εcc was lower in DMD patients (-21.7±3.8 vs. -19.8±4.2, p=0.01; normal vs. DMD). Further, segmental εcc was lower in the anterior segment (-23.0±6.1% vs. -18.9±7.0%, p=0.001; normal vs. DMD), inferior segment (-20.7±5.16% vs. -17.7±6.1%, p=0.003; normal vs. DMD), and inferolateral segment (-18.3±6.2% vs. -15.9±6.7%, p=0.04; normal vs. DMD).
Conclusion In the present study we demonstrate that TTE detects both global and segmental εcc abnormalities (anterior, inferior, and inferolateral segments) in young DMD patients when FS is normal. This is consistent with previous pathological studies in which fibrosis was seen in similar segments in DMD-associated cardiac disease. These novel findings substantiate that the disease process is present in the myocardium long before standard measures detect global dysfunction. Further investigation is needed to determine whether segmental strain can be used to guide early treatment.
- © 2011 by American Heart Association, Inc.