Extracellular Volume Fraction Analysis on Cardiac Computed Tomography Is Useful for Predicting the Prognosis of Hypertrophic Cardiomyopathy

Extracellular volume fraction (ECV) analysis on computed tomography (CT) is now available. The purpose of this study was to assess the usefulness of CT-derived ECV analysis for predicting outcomes in patients with hypertrophic cardiomyopathy (HCM). One hundred and one HCM patients (67 males, 66 ± 11 years old) who received cardiac CT between January 2009 and December 2021 were included. We measured left ventricular (LV) ECV (LV-ECV) on CT and investigated the relationship between LV-ECV and the major adverse cardiac events (MACE) after CT. Fifteen patients (15%) experienced MACE. The patients with MACE had a significantly higher LV-ECV, left atrial diameter, LV end-systolic diameter, and lower LVEF than those without MACE. The proportion of dilated phase HCM was significantly higher in the patients with MACE than those without MACE. LV-ECV and LVEF were significant predictors of MACE based on the multivariate analysis by Cox proportional hazards model. The optimal threshold of LV-ECV to predict MACE was 37.6% based on the receiver operating characteristic analysis. The patients with LV-ECV ≥ 37.6% (30 patients) experienced significantly higher MACE than those with LV-ECV < 37.6% (p < 0.001). CT-derived ECV analysis suggested potential usefulness for predicting MACE in patients with HCM.