The density of crown-like structures in epicardial adipose tissue could play a role in cardiovascular diseases

Purpose The visceral fat of patients affected by abdominal obesity is inflamed, and the main histopathologic feature is the high density of crown-like structures (CLS). Epicardial adipose tissue (EAT) is a visceral fat of paramount importance for its relationships with coronary vessels and myocardium. Its inflammation in patients with abdominal obesity could be of clinical relevance, but histopathological studies on CLS density in EAT are lacking. This study aimed to assess the histopathology of EAT biopsies obtained from patients undergoing open-heart surgery. Methods We collected EAT biopsies from 10 patients undergoing open-heart surgery for elective coronary artery bypass grafting (CABG) (n = 5) or valvular replacement (VR) (n = 5). Biopsies were treated for light microscopy and immunohistochemistry. We quantify the CLS density in each EAT sample. Results Despite all patients having abdominal obesity, in EAT samples, no CLS were detected in the VR group; in contrast, CLS were detected in the CABG group (about 17 CLS/10(4) adipocytes vs. 0.0 CLS/10(4) adipocytes, CABG vs. VR group, respectively). An impressive density of CLS (100 times that of other patients) was found in one patient (LS) in the CABG group that had a relevant anamnestic aspect: relatively rapid increase of weight gain, especially in abdominal adipose tissue, coincident with myocardial infarction. Conclusions CLS density could be an important predictive tool for cardiovascular diseases. Furthermore, the LS case implies a role for timing in weight gain.