Submission
| Title: |
4D Cardiac Magnetic Resonance Strain Characterizes Cardiomyopathy Severity in Duchenne Muscular Dystrophy |
| Co-Authors: |
Earl, Conner, Weldon School of Biomedical Engineering, Purdue University; Larry W. Markham- Riley Children’s Hospital at Indiana University Health, Division of Pediatric Cardiology, Indianapolis; Jonathan H. Soslow- Vanderbilt University School of Medicine; Craig J. Goergen- Weldon School of Biomedical Engineering, Purdue University |
Abstract
Background/Significance/Rationale: Cardiomyopathy (CM) is the most common cause of death in Duchenne muscular dystrophy (DMD), but the severity and pace of CM progression is variable. Identification of biomarkers that associate with severity could allow clinicians to personalize cardiac therapy. Our objective was to determine whether novel 4D (3D+time) cardiac magnetic resonance (CMR) strain analysis could characterize CM severity. We hypothesized that the magnitude of regional strains (circumferential-Ecc, radial-Err, and surface area-Ea) would be significantly different between groups with mild, moderate, and severe CM.
Methods: We analyzed short-axis cine CMR image stacks from 43 DMD patients (median age: 12.23 [10.6-16.5]; [interquartile range]) and 25 male healthy controls (median age: 16.2 [13.3-20.7]). CMR images were compiled into 4D sequences for feature-tracking strain analysis using custom-built software. Unpaired t-test were used to determine statistical significance
Results/Findings: DMD patients had a range of CM severity: 15 (35% of total) had left ventricular ejection fraction (LVEF) >55% with no findings of myocardial delayed enhancement (MDE; Group A), 15 (35%) had MDE with LVEF>55% (Group B) and 13 (30%) had MDE with LVEF<55% (Group C). Basal peak Ecc magnitude was significantly decreased between controls and DMD groups B (p=0.003) and C (p<0.001), but not group A (p=0.604). Basal peak Err showed significant differences between controls and DMD groups A, B, and C (p<0.001 for all). Basal peak Ea showed differences between controls and DMD groups B (p<0.001) and C (p<0.001) but not A (p=0.260). Basal peak Ecc and Ea were also significantly different between DMD groups A and C (p=0.004 and p=0.039 respectively).
Conclusions/Discussion: Strain analysis of 3D cine CMR images in DMD patients generates localized kinematic parameters that strongly differentiate groups with different disease severity.
Translational/Human Health Impact: The imaging metrics and methods shown here could guide personalized therapeutic intervention and enhance clinical trials aimed to improve outcomes and therapies in DMD.
