Ventricular Hinge Point Fibrosis as a Pathological Marker of Hypertrophic Cardiomyopathy in the Absence of Significant Left Ventricular Hypertrophy?

Abstract

A 54-year-old woman presented with presyncope and nonsustained ventricular tachycardia. Cardiac magnetic resonance imaging showed normal cardiac dimensions and left ventricular function. Late gadolinium enhancement was noted at the anterior and posterior right ventricular/left ventricular hinge points. Repeat cardiac magnetic resonance imaging at 1 year confirmed persistence of hinge point enhancement. Hypertrophic cardiomyopathy genotyping revealed the common C to T substitution at coding nucleotide 1504 of MYBPC3, c1504C>T. This variant has previously been reported as pathogenic in hypertrophic cardiomyopathy. Our case suggests that late gadolinium enhancement at the hinge points of nonhypertrophied hearts may account for clinically symptomatic ventricular arrhythmia.