The Impact of Weight Loss Interventions on Ventricular Dysfunction in Pediatric Patients with T2DM: Evaluated with CMR

Abstract

Type II Diabetes Mellitus (T2DM) is a global health concern characterized by insulin resistance and/or deficiency, resulting in elevated blood glucose levels. Cardiac dysfunction in DCM manifests initially with LV hypertrophy, fibrosis, and diastolic dysfunction, often leading to heart failure with normal ejection fraction (HFNEF); its effects on the right heart are less understood. T2DM incidence is increasing among younger populations in which cardiac dysfunction could have significant impact on longevity. This study aimed to characterize left and right ventricular function at baseline in a cohort of morbidly obese children with T2DM (N=17), and to track ventricular function response to vertical sleeve gastrectomy (VSG). Participants underwent cardiac MRI prior to surgery and at 3 months and 12 months following VSG. The cardiac data was labeled by contouring the end-diastolic and end-systolic phases of each cardiac cycle using Function SAX, an offline commercial software (Cvi42, v.5.11.2; Circle Cardiovascular Imaging, Calgary, Canada), to extract heart rate, LV mass, and bilateral systolic volume, end-diastolic volume, end-systolic volume, ejection fraction, and cardiac output. Additional results were obtained to track the participant responses after VSG, including measurements such as weight and A1C. Summary results suggest blood volume reduction due to weight loss. Mean LV EF was never below 50%, suggesting that there was no systolic dysfunction among these patients. RV EF did not significantly change after surgery overall, but one patient showed initial RV systolic dysfunction with an EF of 40.2% which improved to 49.3%. Additionally, a linear mixed model of the volumes as a function of weight suggested that the RV responded more homogeneously across subjects than the LV. Notably, sex specific differences in response were noted in multiple areas of analysis. However, this was a small study, and more work is needed to fully understand these findings.