Changes in the Structure, Function, and Fat Content of the Heart in Patients with Obesity After Bariatric Surgery—A Prospective Magnetic Resonance Imaging Study

Changes in myocardial fat in addition to changes in cardiac structure and function have not been accurately evaluated in obese patients following surgery.

Forty-four obese patients who underwent sleeve gastrectomy and completed preoperative and postoperative cardiac magnetic resonance imaging (CMR) before surgery and at 1, 3, and 6 months after surgery were enrolled, and their clinical and laboratory data were collected. The differences and correlations between clinical, laboratory, and CMR parameters between the preoperative and postoperative groups were analysed.

The left ventricular mass (LVM), left ventricle cardiac output (LVCO), pericardial adipose tissue volume (PATV), and myocardial proton density fat fraction (M-PDFF) decreased after surgery (all P < 0.05). The left ventricle global longitudinal strain increased at 6 months after surgery (P = 0.004). A decrease in BMI was positively correlated with the LVCO (r = 0.58, P < 0.001) at 3 months after surgery and was positively correlated with the LVM and PATV (r = 0.54, P < 0.05) at 6 months after surgery. Six months after surgery, the changes in PATV were positively correlated with the changes in triglycerides (r = 0.61, P < 0.01). There was a moderately positive correlation between the decrease in the LVM and PATV (r = 0.54 ~ 0.71, P < 0.02) after surgery.

After surgery, the cardiac structure and function of obese patients significantly improved, the PATV and M-PDFF decreased, and there was a correlation between the structure and function of the heart and several clinical and laboratory indicators.