Myocarditis in Duchenne Muscular Dystrophy After Changing Steroids

Area of Science:

• Cardiology
• Neurology
• Genetics

Background:

• Duchenne muscular dystrophy (DMD) frequently leads to cardiac dysfunction, a major cause of mortality.
• Myocardial inflammation, termed dystrophinitis, presents as myocarditis in DMD patients.
• Guideline-directed medical therapy, including steroids and regular cardiac surveillance, is crucial for managing DMD-associated cardiomyopathy.

Observation:

• A case report details an 18-year-old male with DMD who developed steroid withdrawal-induced myocarditis.
• The patient experienced acute chest pain, ECG changes, elevated cardiac enzymes, and cardiac magnetic resonance (CMR) findings consistent with myocarditis.
• These symptoms arose after abruptly switching from deflazacort to an underdosed prednisone regimen.

Findings:

• Abruptly stopping deflazacort and switching to prednisone led to increased myocardial inflammation, edema, and fibrosis.
• Following the restart of deflazacort, the patient's symptoms resolved.
• Subsequent CMR imaging demonstrated a decrease in myocardial edema and improved left ventricular function.

Implications:

• This case underscores the risks of discontinuing or altering corticosteroid therapy in DMD patients.
• It highlights the utility of CMR in diagnosing myocardial inflammation and assessing treatment response in DMD.
• Maintaining consistent and appropriate steroid therapy is vital for preventing and managing cardiac complications in DMD.