Usefulness of delayed enhancement by magnetic resonance imaging in hypertrophic cardiomyopathy as a marker of disease and its severity

The aim of the present study was to evaluate, in patients with hypertrophic cardiomyopathy (HC), the association between late gadolinium enhancement and clinical end points, such as nonsustained ventricular tachycardia, arrhythmic risk factors, New York Heart Association class, symptoms, and left ventricular functional parameters. A total of 20 normal subjects (mean age 38 years, 16 men) and 100 patients with HC (mean age 46 years, 70 men) were enrolled in the present study. In the late gadolinium enhancement images, the extent of unenhanced, mildly enhanced, and higher enhanced myocardium was measured. Higher enhancement was present in 80% of the HC population and was significantly greater in patients with a New York Heart Association class >1. Mild enhancement was present in all the patients with HC. Receiver operating characteristic analysis revealed that a cutoff of >4.9% of mild enhancement had 100% sensitivity and 86% specificity to predict the occurrence of nonsustained ventricular tachycardia, and a cutoff of >2.4% of hyperenhancement had 77% sensitivity and 96% specificity. In conclusion, late gadolinium enhancement was associated with nonsustained ventricular tachycardia, arrhythmic risk factors, and worse New York Heart Association class.