Preoperative cardiac screening using NT-proBNP in obese patients 50 years and older undergoing bariatric surgery: a study of 310 consecutive patients

Background: Obesity is associated with cardiovascular (CV) risk factors and diseases. Because bariatric surgery is increasingly performed in relatively elderly patients, a risk for pre- and postoperative CV complications exists. Objectives: We aimed to assess the value of plasma N-terminal-probrain natriuretic peptide (NT-proBNP) as a CV screening tool. Setting: High-volume bariatric center. Methods: Between June 2019 and January 2020, all consecutive bariatric patients 50 years and older underwent preoperative NT-proBNP assessment in this cohort study to screen for CV disease. Patients with elevated NT-proBNP (≥125 pg/mL) were referred for further cardiac evaluation, including electrocardiography and echocardiography. Results: We included 310 consecutive patients (median age, 56 years; 79% female; body mass index = 43±6.5 kg/m²). A history of CV disease was present in 21% of patients, mainly atrial fibrillation (7%) and coronary artery disease (10%). A total of 72 patients (23%) had elevated NT-proBNP levels, and 67 of them underwent further cardiac workup. Of these 67 patients, electrocardiography (ECG) showed atrial fibrillation in 7 patients (10%). On echocardiography, 3 patients had left ventricular ejection fraction (LVEF) <40%, 9 patients had LVEF 40%–49%, and 13 patients had LVEF ≥50% with structural and/or functional remodeling. In 2 patients, elevated NT-proBNP prompted workup leading to a diagnosis of coronary artery disease and consequent percutaneous coronary intervention in 1 patient. Conclusions: Elevated NT-proBNP levels are present in 23% of patients 50 years and older undergoing bariatric surgery. In 37% of them, there was echocardiographic evidence for structural and/or functional remodeling. Further studies are needed to assess if these preliminary results warrant routine application of NT-proBNP to identify patients at risk for CV complications after bariatric surgery.