Bariatric surgery and cardiovascular outcomes: a systematic review

Purpose To quantify the impact of bariatric surgery on cardiovascular (CV) risk factors, and on cardiac structure and function. Data sources Three major databases (PubMed, Medline and Cochrane) were searched for original studies written in English. Study selection Original articles reporting CV risk factors or non-invasive imaging parameters for patients undergoing bariatric surgery, from January 1950 to June 2012. Data extraction Data extraction from selected studies was based on protocol-defined criteria that included study design, methods, patient characteristics, surgical procedures, weight loss, changes in CV risk factors, cardiac structure and cardiac function postoperatively. Data synthesis 73 CV risk factor studies involving 19 543 subjects were included (mean age 42 years, 76% female). Baseline prevalence of hypertension, diabetes and hyperlipidaemia were 44%, 24%, and 44%, respectively. Mean follow-up was 57.8 months (range 3-176) and average excess weight loss was 54% (range 16-87%). Postoperative resolution/improvement of hypertension occurred in 63% of subjects, of diabetes in 73% and of hyperlipidaemia in 65%. Echocardiographic data from 713 subjects demonstrated statistically significant improvements in left ventricular mass, E/A ratio, and isovolumic relaxation time postoperatively. Limitations Diagnostic criteria, CV risk factor reporting, and imaging parameters were not uniform across all studies. Study groups were heterogeneous in their demographics, operative technique and follow-up period. Conclusions This systematic review highlights the benefits of bariatric surgery in reducing risk factors for CV disease. There is also evidence for left ventricular hypertrophy regression and improved diastolic function. These observations provide further evidence that bariatric surgery enhances future CV health for obese individuals.