Hypertrophic Cardiomyopathy in the Absence of "Hypertrophy": A Precision Medicine Reappraisal.

Fixed wall thickness cutoffs have historically defined hypertrophic cardiomyopathy (HCM), yet this rigid approach overlooks patients with early, segmental, or morphologically subtle disease. Subthreshold phenotypes-particularly in women, individuals with short stature, and those with apical or focal variants-may not meet conventional criteria despite exhibiting pathologic features. This article examines the limitations of absolute diagnostic thresholds and advocates for a precision medicine framework. Integrating cardiac magnetic resonance imaging with individualized metrics and architectural markers enhances diagnostic accuracy, identifies nonclassical presentations, and facilitates earlier disease recognition, ultimately improving care across the heterogeneous spectrum of HCM.