Can patients with Duchenne muscular dystrophy (DMD) experience chest pain?

Chest Pain in Duchenne Muscular Dystrophy (DMD)

Yes, patients with Duchenne muscular dystrophy can experience chest pain, particularly as a manifestation of the cardiomyopathy that develops as part of the disease progression. 1

Cardiac Involvement in DMD

• DMD is an X-linked genetic disorder affecting approximately 1 in 5000 live male births, characterized by progressive loss of muscle function due to mutations in the dystrophin gene 2
• Historically, respiratory failure was the most common cause of death, but with improved respiratory support, cardiomyopathy has become an increasingly important source of morbidity and mortality 2
• Cardiomyopathy in DMD typically presents as a hypokinetic, dilated phenotype that progressively worsens with age 3

Chest Pain Presentation in DMD

• Chest pain with troponin elevation has been documented in DMD patients, indicating acute cardiac events that may represent significant progression of cardiomyopathy 1
• These episodes can present as:
  • Primary complaint of acute chest pain 1
  • Secondary myocardial injury during systemic illness requiring hospitalization 1
• During these events, patients may show:
  • Diffuse ST changes on electrocardiogram 1
  • Elevated troponin levels (which typically normalize with supportive care) 1
  • Deterioration of left ventricular ejection fraction (LVEF) 1
  • Increased late gadolinium enhancement on cardiac MRI, indicating progression of myocardial fibrosis 1

Cardiac Manifestations in DMD

• Only about 30% of boys with DMD have cardiac symptoms at the time of cardiomyopathy diagnosis, making it often clinically silent 2
• DMD cardiomyopathy is characterized by:
  • Less left ventricular enlargement at diagnosis compared to other forms of dilated cardiomyopathy 2
  • Higher mortality rate than other dilated cardiomyopathies 2
  • Typical ECG findings including increased R/S ratio in right precordial leads, deep Q waves in lateral leads, conduction abnormalities, and arrhythmias 4
  • Subepicardial fibrosis in the inferolateral wall as the typical cardiac MRI lesion 4

Clinical Implications and Management

• Chest pain episodes with troponin elevation may represent an important pathophysiological mechanism in cardiomyopathy progression in DMD patients 1
• This clinical presentation is under-recognized but significant as it may indicate acute left ventricular dysfunction and development or progression of myocardial fibrosis 1
• Regular cardiac care is crucial in DMD management 3
• Early recognition and prophylactic use of angiotensin converting enzyme inhibitors (ACEIs) are the mainstay therapeutic strategy to delay the incidence of DMD cardiomyopathy 3, 4
• Addition of beta-blockers to ACEIs has shown improvement in left ventricular systolic function in muscular dystrophy patients 4

Monitoring Recommendations

• Cardiac MRI is increasingly recommended for surveillance of myocardial damage and function in DMD patients, as it can detect early changes and fibrosis that may not be visible on echocardiography 2
• Tissue Doppler echocardiography can be used to identify early changes of cardiomyopathy and detect progressive cardiac damage 4
• Patients presenting with chest pain should receive comprehensive cardiac evaluation including ECG, troponin measurement, and cardiac imaging 1

In conclusion, chest pain in DMD patients should be taken seriously as it may indicate significant cardiac involvement and progression of cardiomyopathy, which is a leading cause of morbidity and mortality in this population.