Effect of bariatric surgery on cardiac structure and function in obese patients: Role of the renin-angiotensin system

Abstract

Echocardiographic alterations have been described in obesity, but their modifications after bariatric surgery (BS) and mechanisms are little known, mostly in normotensive patients. We aimed to analyze cardiac changes 1 year post-BS and to explore possible mechanisms. A cohort of patients with severe obesity (58% normotensives) were prospectively recruited and examined before surgery and after 12 months. Clinical and echocardiographic data, 24 h BP, renin-angiotensin-aldosterone system (RAAS) components, cytokines, and inflammatory markers were analyzed at these two time points. Overall reduction in body weight was mean (IQR) = 30.0% (25.9–33.8). There were statistically significant decreases in left ventricle mass index2.7(LVMI)2.7, septum thickness (ST), posterior wall thickness (PWT), relative wall thickness (RWT), and E/e’, both in the whole cohort and in patients without RAAS blockers (p ≤.04 for all). Plasma renin activity (PRA) decreased from (median, IQR) = 0.8 (0.3;1.35) to 0.4 (0.2;0.93) ng/ml/h, plasma aldosterone from 92 (58.6;126) to 68.1 (56.2;83.4) ng/dl, and angiotensin-converting enzyme (ACE)-2 activity from 7.7 (5.7;11.8) to 6.8 (5.3;11.2) RFU/µl/h, p