E2841. Exercise and Drop – Sudden Cardiac Death: A Primer on Hypertrophic Cardiomyopathy for the Radiologist In-Training
  1. Jolanta Norelli; Stony Brook University Hospital
  2. Max Hao; Stony Brook University Hospital
  3. Katherine Chung; Stony Brook University Hospital
  4. Lachlan Smith; Stony Brook University Hospital
The purpose of this educational exhibit is to discuss the different pathophysiological types of hypertrophic cardiomyopathy (HCM) based on pertinent imaging findings on cardiac MRI illustrated by representative case examples. Case examples include: asymmetric - (most common) basal septal thickness > 15 mm, ratio of the septal thickness to inferior mid-ventricular wall > 1.5, symmetric/concentric - diffuse thickening of the left ventricle (LV) and associated decrease in the size of LV cavity, apical – also known as Yamaguchi syndrome, apical septal thickness > 15 mm, midventricular - (rare) localized midventricular thickness, and mass-like/Tumefactive - focal thickening simulating a mass. Management of different types of HCM includes: lifestyle changes, genetic counseling/screening, pharmacologic, percutaneous alcohol-septal ablation (ASA), surgical myomectomy, and implantable defibrillator.

Educational Goals / Teaching Points
Describe the pathophysiological types of hypertrophic cardiomyopathy (HCM). Review the imaging features typical of HCM with various subtype case examples. Discuss treatment management options.

Key Anatomic/Physiologic Issues and Imaging Findings/Techniques
Pertinent imaging findings on cardiac MRI include: LV hypertrophy, inversion recovery (IR) imaging with fibrosis characterized by foci of delayed gadolinium enhancement of involved thickened myocardium, LV outflow track (LVOT) obstruction - peak gradient at LVOT or mid-LV cavity > 30 mmHg, if present, systolic anterior motion of anterior mitral leaflet (SAM), if present, and burned-out phase - late stage disease characterized by LV ejection fraction < 50%.

There are various pathophysiological types of HCM with different treatment and prognosis. Diagnosis is based on a combination of clinical symptoms, genetic testing, and pertinent imaging findings on cardiac MRI.