Cardiovascular Changes After Gastric Bypass Surgery: Involvement of Increased Secretions of Glucagon-Like Peptide-1 and Brain Natriuretic Peptide.

ABSTRACT

BACKGROUND: Obesity induces cardiovascular alterations, including cardiac hypertrophy, impaired relaxation, and heart rate variability (HRV), which are associated with increased mortality. Gastric bypass surgery (GBP) reduces cardiovascular mortality, but the mechanisms involved are not clearly established. To date, the implication of postsurgical hormonal changes has not been tested. Our aim was to study the relationships between the evolution of cardiovascular functions after GBP and changes in metabolic and hormonal parameters, including glucagon-like peptide-1 (GLP-1) and brain natriuretic peptide (N-terminal pro-brain natriuretic peptide (NT-proBNP)). METHODS: Echocardiographic parameters, 24-h rhythmic Holter recording, plasma concentrations of GLP-1 before and after a test meal, and fasting NT-proBNP were assessed in 34 patients (M/F 2/32, age 36 ± 11 years, BMI 46 ± 6 kg/m(2)), before and 1 year after GBP. RESULTS: After GBP, excess weight loss was 79 ± 20%. Blood pressure (BP), heart rate, and left ventricular mass decreased, while HRV and diastolic function (E/A ratio) improved. Plasma concentrations of NT-proBNP and postprandial (PP) GLP-1 increased. Changes in cardiovascular parameters were related to BMI and insulin sensitivity. Furthermore, the decrease in BP was independently associated with the increase of PP GLP-1 level and HRV was positively associated with NT-proBNP concentration after surgery. CONCLUSIONS: The increase in endogenous GLP-1 observed after GBP was associated with decreased BP but not with improvement of other cardiovascular parameters, whereas the increase in NT-proBNP, within the physiological range, was associated with improved HRV.