Left Ventricular Magnetic Resonance Imaging Strain Predicts the Onset of Duchenne Muscular Dystrophy-Associated Cardiomyopathy

Background: Early detection of left ventricular (LV) dysfunction before the onset of overt Duchenne muscular dystrophy-associated cardiomyopathy (DMDAC) may direct clinical management to slow onset of dysfunction. We aimed to assess whether LV strain will predict those who develop DMDAC. Methods: We performed a single center retrospective case control study of patients with Duchenne muscular dystrophy who underwent serial cardiac magnetic resonance between 2006 and 2019. Patients with Duchenne muscular dystrophy with an LV ejection fraction >= 55% on >= 1 cardiac magnetic resonance were identified and grouped into age-matched +DMDAC and -DMDAC. Within 3 years, +DMDAC had a subsequent cardiac magnetic resonance with a decline in LV ejection fraction >= 10% and absolute LV ejection fraction <= 50%. -DMDAC maintained an LV ejection fraction >= 55% on serial cardiac magnetic resonances. Two-dimensional and 3-dimensional global radial strain, global circumferential strain (GCS), and global longitudinal strain were measured using tissue tracking software and their ability to predict DMDAC onset was assessed. Multivariable analysis adjusted for late gadolinium enhancement. Results: Thirty +DMDAC and 30 age-matched -DMDAC patients were included with a total of 164 studies analyzed. Before DMDAC onset, 2-dimensional global radial strain and GCS were significantly worse in +DMDAC compared with -DMDAC (25.1 +/- 6.0 versus 29.0 +/- 6.3, P=0.011; -15.4%+/- 2.4 versus -17.3%+/- 2.6, P=0.003). Three-dimensional GCS and global radial strain had similar findings. Among strain measures, 3-dimensional GCS had the highest area under the curve to predict DMDAC in our cohort. These findings persisted after adjusting for the presence of late gadolinium enhancement. Conclusions: Reduced global radial strain and GCS may predict those at risk for developing DMDAC before onset of LV dysfunction and its clinical utility warrants further exploration.