Role of cardiovascular magnetic resonance in diagnosis and management of muscular dystrophies

Muscular dystrophies encompass a heterogeneous spectrum of inherited myopathies characterized by progressive skeletal muscle degeneration frequently accompanied by life-threatening cardiac involvement. Cardiovascular magnetic resonance (CMR) has become the reference non-invasive imaging modality for the detection, characterization, and longitudinal monitoring of cardiomyopathy involvement across this group of disorders. This state-of-the-art review summarized contemporary evidence on the diagnostic and prognostic value of CMR in the most prevalent muscular dystrophies, including Myotonic dystrophy, Duchenne and Becker muscular dystrophies, Emery-Dreifuss muscular dystrophy, laminopathies, facioscapulohumeral muscular dystrophy, and mitochondrial myopathies. CMR uniquely enables high-resolution assessment of ventricular volumes and function, tissue characterization through late gadolinium enhancement (LGE) and parametric mapping (native T1, T2, extracellular volume fraction), and quantitative strain imaging. These techniques uncover subclinical myocardial involvement years before overt dysfunction occurs, providing a robust substrate for early therapeutic intervention. Disease-specific CMR signatures, such as inferolateral subepicardial fibrosis in dystrophinopathies or mid-wall septal enhancement in laminopathies, allow for refined etiological diagnosis and targeted risk stratification. LGE burden and distribution are independently associated with ventricular arrhythmias and adverse cardiac events, transcending the limitations of traditional criteria based on left ventricular ejection fraction for implantable cardioverter-defibrillator selection. Emerging evidence further supports the integration of CMR biomarkers into genotype-guided management strategies and prospective therapeutic trials.