Subclinical Left Ventricular Dysfunction in Severe Obesity and Reverse Cardiac Remodeling after Bariatric Surgery

Obesity is associated with an increased cardiovascular risk. This study aimed to assess the role of echocardiography in the early detection of subclinical cardiac abnormalities in a cohort of obese patients with a preserved ejection fraction (EF) undergoing bariatric surgery.

Forty consecutive severely obese patients (body mass index≥35 kg/m2) referring to our center for bariatric surgery were enrolled in this prospective cohort study. Despite a baseline EF of 61% ± 3%, almost half patients (43%) had a systolic dysfunction (SD) defined as global longitudinal strain (GLS)>-18%, and most of them (60%) had left ventricular hypertrophy (LVH) or concentric remodeling (CR). At 10-months after surgery, body weight decreased from 120 ± 15 kg to 83 ± 12 kg, body mass index from 44 ± 5 kg/m² to 31 ± 5 kg/m² (both P < 0.001). Septal and left ventricular posterior wall thickness decreased respectively from 10 ± 1 mm to 9 ± 1 mm (P = 0.004) and from 10 ± 1 mm to 9 ± 1 mm (P = 0.007). All systolic parameters improved: EF from 61% ± 3% to 64% ± 3% (P = 0.002) and GLS from -17% ± 2% to -20% ± 1% (P < 0.001). Epicardial fat thickness reduction (from 4.7 ± 1 mm to 3.5 ± 0.7 mm, P < 0.001) correlated with the reduction of left atrial area (P < 0.001 R = 0.35) and volume (P = 0.02 R = 0.25). Following bariatric surgery, we observed a reduced prevalence of LVH/CR (before 60%, after 22%, P = 0.001) and a complete resolution of preclinical SD (before 43%, after 0%, P < 0.001). Moreover, a postoperative reduction of at least 30 kg correlated with regression of septal hypertrophy (P < 0.001).

Obese patients candidate to bariatric surgery have an high prevalence of preclinical SD and LVH/CR, early detectable with echocardiography. Bariatric surgery is associated with reverse cardiac remodeling; it might also have a preventive effect on atrial fibrillation occurrence by reducing its substrate.