Normalization of Cardiac Function After Bariatric Surgery Is Related to Autonomic Function and Vitamin D.

PURPOSE

Subclinical cardiac dysfunction is common in patients with obesity. Bariatric surgery is associated with normalization of subclinical cardiac function in 50% of the patients with obesity. The aim of this study was to identify predictors for a lack of improvement of subclinical cardiac dysfunction 1-year post-bariatric surgery.

METHODS

Patients who were referred for bariatric surgery were enrolled in a longitudinal study. Inclusion criteria were age 35-65 years and BMI ≥ 35 kg/m. Patients with a suspicion of or known cardiovascular disease were excluded. Conventional and advanced echocardiography, Holter monitoring, and blood tests were performed pre- and 1-year post-bariatric surgery. Subclinical cardiac dysfunction was defined as either a reduced left ventricular ejection fraction, decreased global longitudinal strain (GLS), diastolic dysfunction, arrhythmia, or an increased BNP or hs Troponin I.

RESULTS

A total of 99 patients were included of whom 59 patients had cardiac dysfunction at baseline. Seventy-two patients completed the 1-year follow-up after bariatric surgery. There was a significant reduction in weight and cardiovascular risk factors. Parameters of cardiac function, such as GLS, improved. However, in 20 patients cardiac dysfunction persisted. Multivariate analysis identified a decreased heart rate variability (which is a measure of autonomic function), and a decreased vitamin D pre-surgery as predictors for subclinical cardiac dysfunction after bariatric surgery.

CONCLUSION

Although there was an overall improvement of cardiac function 1-year post-bariatric surgery, autonomic dysfunction and a decreased vitamin D pre-bariatric surgery were predictors for a lack of improvement of subclinical cardiac dysfunction.