Effects of bariatric surgery on pericardial ectopic fat depositions and cardiovascular function

Abstract

OBJECTIVE: Cardiac ectopic fat depositions are thought to play a role in the pathogenesis of cardiovascular disease (CVD), the main cause of death in patients with type 2 diabetes. Diet-induced weight loss results in a decrease in cardiac ectopic fat stores, however if this is the same for surgically induced weight loss is less clear. Therefore, we assessed myocardial triglyceride (TG) content, pericardial fat and cardiac function in obese patients with insulin-dependent type 2 diabetes before and 16 weeks after Roux-en-Y gastric bypass (RYGB) surgery. PATIENTS: Ten obese patients with insulin-dependent type 2 diabetes [40% male, age 53·7 ± 8·9 years (mean ± SD)] scheduled to undergo RYGB surgery were included. MEASUREMENTS: Ectopic fat accumulation and cardiovascular function were assessed with magnetic resonance (MR) imaging and myocardial TG content with MR spectroscopy before and 16 weeks after RYGB surgery. RESULTS: Body mass index decreased from 41·3 ± 4·3 at baseline to 34·1 ± 2·8 kg/m(2) (P < 0·001) after 16 weeks. Glycemic control improved as well [HbA1c: 7·8 ± 1·1 to 6·8 ± 1·3% (62 ± 12 to 51 ± 14 mm) (P < 0·05)]. We did not observe an effect of the RYGB surgery on myocardial TG content, cardiac function or pulse wave velocity. There was a greater relative decrease in visceral (-35·5 ± 9·6%) as compared to subcutaneous fat volume (-25·0 ± 6·3%) and in paracardial (-17·3 ±17·2%) as compared to epicardial fat volume (-6·4 ± 6·0%). CONCLUSIONS: This study shows that surgical-induced weight loss leads to a larger decrease in paracardial than epicardial fat. Myocardial TG and cardiovascular function did not change.