Epicardial Adipose Tissue and Extracellular Volume Fraction in Patients with Hypertrophic Cardiomyopathy: A Multi‑center Prognosis Study.

Rationale And Objectives: Epicardial adipose tissue (EAT) is thought to have a deleterious effect on the progression of myocardial disease; the extracellular volume (ECV) fraction has been validated by histology to correlate with adverse myocardial remodeling. The aim of this study was to investigate the prognostic value of EAT volume index (EATVI) and ECV in patients with hypertrophic cardiomyopathy (HCM).

Materials And Methods: ECV and EAT were measured using cardiac magnetic resonance (CMR) imaging in 201 subjects with HCM. All patients were followed up prospectively. Major adverse cardiovascular events (MACEs) were categorized into primary and secondary endpoint events. The primary endpoint was a composite of cardiac death, heart transplant, and cardiopulmonary resuscitation following syncope. The secondary endpoint was defined as rehospitalization for heart failure (HF).

Results: After 26±16 months of follow-up, 43 patients experienced MACEs (14 patients experienced a primary endpoint, and 29 patients experienced a secondary endpoint). Patients suffering from MACEs had significantly higher ECV and EATVI (p<0.001). After adjustment for body mass index (BMI), EATVI showed a significant correlation with ECV (r=0.424, p<0.001) among HCM patients. In the Kaplan-Meier analysis, the incidence of MACE was significantly higher in patients with increased ECV (p<0.001) and higher EATVI (p<0.001). In multivariate Cox regression analysis, ECV (HR=1.12, p<0.001) and EATVI (HR=1.31, p<0.001) were significantly associated with MACEs.

Conclusion: In patients with HCM, ECV and EATVI measured by CMR are strong predictors of MACEs and improve risk stratification.

Clinical Implication: Extracellular volume fraction and epicardial adipose tissue are associated with major adverse cardiovascular events in patients with hypertrophic cardiomyopathy and can improve their risk stratification.