Imaging-Based Risk Stratification for Sudden Cardiac Death in Hypertrophic Cardiomyopathy: Current Evidence and Clinical Perspectives.

Hypertrophic cardiomyopathy (HCM) is a common inherited myocardial disorder and a leading cause of sudden cardiac death (SCD) across all age groups. Accurate risk stratification remains a clinical challenge, as conventional algorithms fail to fully capture the heterogeneous arrhythmic substrate of the disease. In recent years, cardiac imaging has emerged as a pivotal tool for refining SCD prediction by providing detailed structural, functional, and tissue-characterisation data. This review offers a comprehensive synthesis of imaging-derived predictors of SCD in HCM. We examine established echocardiographic markers, including maximal left ventricular wall thickness, left ventricular ejection fraction and left ventricular outflow tract obstruction, together with advanced cardiovascular magnetic resonance parameters such as late gadolinium enhancement and apical aneurysm detection. In addition, we discuss the emerging role of extracellular volume expansion, quantitative mapping techniques, and strain abnormalities within the framework of contemporary risk stratification models. By bridging imaging biomarkers with underlying pathophysiological mechanisms, this review highlights current evidence, limitations, and future directions to improve precision in SCD risk assessment in HCM.