Open-bore MRI scanner assessment of epicardial adipose tissue after bariatric surgery: a pilot study

Background: The recognition of epicardial adipose tissue (EAT) as a cardiac risk factor has increased the interest in strategies that target cardiac adipose tissue. Aim: The effect of bariatric and metabolic surgery (BMS)-induced weight loss on EAT volume was evaluated in this study. Methods: Fifteen bariatric patients, with (MS) or without (wMS) Metabolic Syndrome, underwent magnetic resonance imaging (MRI) using an open-bore scanner to assess EAT volume, visceral adipose tissue (VAT) thickness, and other cardiac morpho-functional parameters at baseline and 12 months after BMS. Nine patients underwent laparoscopic sleeve gastrectomy (LSG), and 6 patients underwent Roux-en-Y Gastric Bypass (RYGBP). Results: EAT volume significantly decreased in all the patients 12 months post-BMS from 91.6 cm3 to 67.1 cm3; p = 0.0002 in diastole and from 89.4 cm3 to 68.2 cm3; p = 0.0002 in systole. No significant difference was found between the LSG and RYGBP group. Moreover, EAT volume was significantly reduced among wMS compared with MS. In particular, EAT volume in diastole was significantly reduced from 80.9 cm3 to 54.4 cm3; p = 0.0156 in wMS and from 98.3 cm3 to 79.5 cm3; p = 0.031 in MS. The reduction was also confirmed in systole from 81.2 cm3 to 54.1 cm3; p = 0.0156 in wMS and from 105.7 cm3 to 75.1 cm3; p = 0.031 in MS. Finally, a positive correlation was found between EAT loss, BMI (r = 0.52; p = 0.0443) and VAT (r = 0.66; p = 0.008) reduction after BMS. Conclusion: These findings suggest that EAT reduction may be a fundamental element for improving the cardio-metabolic prognosis of bariatric patients. Moreover, this is the first study performed with an open-bore MRI scanner to measure EAT volume.