Structural and Functional Characterization of the Aorta in Hypertrophic Obstructive Cardiomyopathy | Circulation: Heart Failure
BACKGROUND: Changes in the phenotype and genotype in hypertrophic cardiomyopathy (HCM) are thought to involve the myocardium as well as extracardiac tissues. Here, we describe the structural and functional changes in the ascending aorta of obstructive patients with HCM. METHODS: Changes in the aortic wall were studied in a cohort of 101 consecutive patients with HCM undergoing myectomy and 9 normal controls. Biopsies were examined histologically, immunohistochemically, and by electron microscopy. Changes in protein expression were quantified using morphometry and Western blotting. Pulse wave velocity was measured using cardiac magnetic resonance in 85 patients with HCM and compared with 117 age-matched normal controls. RESULTS: In HCM, the number of medial lamellar units was significantly decreased, associated with an increase in interlamellar distance and aortic wall thickness, as compared with controls. Electron microscopy showed an altered lamellar structure with disorientation of e