Background: Cardiomyopathy is the leading cause of mortality for Becker Muscular Dystrophy (BMD). Risk stratification is challenging due to the wide variation of cardiomyopathy onset, progression, and severity; with cardiomyopathy developing independent of skeletal myopathy progression. We have been performing cardiac magnetic resonance imaging (CMR) routinely by 10 years of age. We hypothesized that BMD patients with late gadolinium enhancement have worse left ventricular ejection fraction (LVEF) and have greater decline on follow-up CMR study
Objectives: We retrospectively reviewed the CMR studies performed between June 2013 and June 2025 and only included patients with at least two studies. The patients were dichotomized into two groups based on LGE findings of the initial CMR study. We collected LGE status, LVEF and age were collected at each study to calculated time between studies, change in LVEF and rate of decline per year. Statistical analysis was performed using Student’s t-test between groups.
Results: There were 75 BMD patients who underwent 150 CMR studies with LGE assessment with CMR. The average age of the first CMR study was 14.8±6.2 (range 8-40) and follow-up at 17.9±6.4 years (9-41). Of these 45/75 (60%) patients had negative LGE and 30/75 (40%) had positive LGE on the first study. The LGE positive group was significantly older (p<0.0001) with average age 18.5±7.4 years (range 9-40 years) compared to 12.3±7.9 years (range 8-22 years). Patients who were LGE positive had a lower mean initial LVEF compared with LGE negative patients (55.1±8.0% vs 62.2±5.3% p-value < 0.0001) and decline in LVEF on follow-up study (48.3±11.1% vs 60.3±6.7% p-value < 0.0001) with no difference in mean follow-up time (2.7±2.0 vs 3.4±2.0 years, p= 0.05). Of the LGE negative patients 13/45 (28.9%) became positive over a 4.2±1.9 years a decline in LVEF from 65.2±5.2% to 55.8±6.9% over a 4.2±1.9-year period. In serial follow up, LGE positive patients showed a statistically significant decline in LVEF of -6.8%±7.8 vs -2.8±6.0%, p =0.007 for an average yearly decline of -3.7±8% per year versus -0.4±2.1% per year, p=0.005, Figure 3. Interestingly, the 13 patients that converted had a decline in LVEF from 65.2±5.2 to 55.8±6.9% with an average LVEF decreased of -9.4% for a decline of 2.4% per year who those who remained negative did not decline +1.7% for a 0.4% positive LVEF change per year.
Conclusions: Our study reported many BMD patients with LGE positive finding