This study is a retrospective analysis of prospectively collected data on 582 obese patients. It was conducted according to the ethical principles stated in the Declaration of Helsinki. Written informed consent was obtained from all subjects. The study protocol was approved by the Regional Ethics Committee. From January 2014 to February 2019, morbid obesity patients who failed previous treatment with SG and referred to our bariatric center in the Department of General and Emergency Surgery of "A. Rizzoli" Hospital in Lacco Ameno (Naples, Italy) for a new bariatric procedure, were considered in the study. Redo surgery was only considered if patients still met the criteria for primary bariatric surgery according to guidelines [body mass index (BMI) >35 kg/m2 with co-morbidities, BMI >40 kg/m2] at the time clinical and anthropometrical revision8. A postoperative follow-up of at least 24 months was also considered inclusion criteria. Exclusion criteria were as follows: patients in whom Sleeve Gastrectomy was already performed as revision surgery; patients underwent any other abdominal surgical procedure after One Anastomosis Gastric Bypass not correlated to the bariatric procedure, the presence at baseline of esophagitis B according to the Los Angeles scale, Hiatal Hernia (HH) > 5 cm and history of GERD-related symptoms (i.e., heartburn, pyrosis, regurgitation) not responsive to proton pump inhibitors and/or severe Lower Esophageal Sfinter incontinence. All procedures were performed by the same experienced bariatric surgeons.
Pre-operative evaluation All patients underwent a multidisciplinary preoperative evaluation including anthropometric measurements (height in cm, weight in kg, Body Mass Index in kg/m2), comorbidity evaluation, preoperative Upper Endoscopy with Helicobacter Pylori test, abdomen ultrasound, chest x-ray and nutritional status evaluation.
Radiographic barium swallow test was performed for the diagnosis of HH or presence of gastric fundus. Barium swallow X-ray protocol consisted of five swallows of barium always using the same amount of liquid; anteroposterior and oblique views were obtained in upright and supine positions. Measurements were done using a standardized protocol: a distance of more than 2 cm between the gastroesophageal junction and the diaphragmatic hiatus was defined as a sliding Hiatal Hernia. Preoperative assessments of patient eligibility for bariatric surgery included consultation with the multidisciplinary committee (surgeon, radiologist, diabetologist and psychiatrist) to exclude patients with non-adjusted eating patterns or eating disorders.
Failure of Sleeve Gastrectomy was defined as a consequence of Insufficient Weight Loss or Weight Regain. Insufficient Weight Loss or Weight Regain were analyzed considering the modifications of the percentage of excess weight loss <50% and/or the percentage of total weight loss <25%. A failure of Sleeve Gastrectomy was recognized if the subject was not able to reduce the Body Mass Index <35 with the persistence of co-morbidity or Body Mass Index <40 at least 2-year after the primary surgery.
