Arrhythmias in the muscular dystrophies

Area of Science:

• Cardiology
• Neurology
• Genetics

Background:

• Muscular dystrophies (MDs) are inherited disorders primarily affecting skeletal muscle.
• Cardiac muscle is also affected, leading to myocardial fibrosis, fatty replacement, and dilated cardiomyopathy.
• Patients with MDs face risks of arrhythmias, conduction disease, bradycardia, and sudden cardiac death.

Purpose of the Study:

• To review cardiac manifestations in various types of muscular dystrophies.
• To discuss the role of electrophysiologists in managing cardiac complications of MDs.
• To highlight current guidelines and emerging strategies for device therapy.

Main Methods:

• Review of literature on cardiac involvement in different MD subtypes.
• Analysis of electrophysiological risks associated with specific MDs.
• Discussion of current treatment paradigms for cardiac arrhythmias and cardiomyopathy in MD patients.

Main Results:

• Duchenne, Becker, and certain limb-girdle MDs commonly develop dilated cardiomyopathy, followed by arrhythmias.
• Myotonic, Emery-Dreifuss, and other limb-girdle MDs often present with conduction disease and arrhythmias, with variable cardiomyopathy.
• Prophylactic implantable cardioverter-defibrillators are increasingly recommended over pacemakers in some MD types.

Conclusions:

• Cardiac involvement is a significant concern in muscular dystrophies, necessitating expert electrophysiological management.
• Device selection (pacemaker vs. ICD) should consider the specific MD type, cardiac status, and respiratory function.
• Proactive cardiac care, including prophylactic device implantation, is crucial for improving survival and quality of life in MD patients.