Atlas of Regional Left Ventricular Scar in Nonischemic Cardiomyopathies: Substrates and Etiologies

: Most acquired and inherited cardiomyopathies are characterized by regional left ventricular involvement and nonischemic myocardial scars, often with a disease-specific pattern. Irrespective of the etiology and pathophysiological mechanisms, myocardial disorders are invariably associated with cardiac fibrosis, which contributes to dysfunction and electrical instability. Accordingly, cardiac magnetic resonance plays a central role in the diagnostic work-up and prognostic risk stratification of cardiomyopathies, particularly with the increasing correlation between genetic background and specific disease phenotype. Starting from pattern and distribution of myocardial fibrosis at cardiac magnetic resonance, we provide a practical regional atlas of nonischemic myocardial scar to guide the diagnostic approach to nonischemic cardiomyopathies.