Surgery for Obesity and Related Diseases ] (2017) 00–00 Original article Factor VIII elevation may contribute to portomesenteric vein thrombosis after laparoscopic sleeve gastrectomy: a multicenter review of 40 patients Manish Parikh, M.D. a,* , Andrew Adelsheimer, B.A. a , Eduardo Somoza, M.D. a , John K. Saunders, M.D. a , Akuezunkpa Ude Welcome, M.D. a , Patricia Chui, M.D. a , Christine Ren-Fielding, M.D. a , Marina Kurian, M.D. a , George Fielding, M.D. a , Ajay Chopra, M.D. b , Richie Goriparthi, M.D. c , Mitchell Roslin, M.D. c , Che Afaneh, M.D. d , Alfons Pomp, M.D. d , Edward Chin, M.D. e , H. Leon Pachter, M.D. a a Department of Surgery NYU Langone Medical Center/Bellevue Hospital Center, New York, New York b Department of Surgery, Jacobi Medical Center, New York, New York c Department of Surgery, Lenox Hill Hospital, New York, New York d Department of Surgery, New York Presbyterian-Weill Cornell, New York, New York e Department of Surgery, Mount Sinai Health System, New York, New York Received July 24, 2017; accepted August 22, 2017 Abstract Background: Portomesenteric vein thrombosis (PMVT) has been increasingly reported after lap- aroscopic sleeve gastrectomy (LSG). Factor VIII (FVIII) is a plasma sialoglycoprotein that plays an essential role in hemostasis. There is increasing evidence that FVIII elevation constitutes a clinically important risk factor for venous thrombosis. Objectives: To report the prevalence of FVIII elevation as well as other clinical characteristics in a multicenter series of patients who developed PMVT after LSG. Setting: University hospitals. Methods: A retrospective review was conducted of all patients that developed PMVT after lapa- roscopic bariatric surgery from 2006 to 2016 at 6 high-volume bariatric surgery centers. Results: Forty patients who developed PMVT postoperatively, all after LSG, were identified. During this timeframe, 25,569 laparoscopic bariatric surgery cases were performed, including 9749 LSG (PMVT incidence after LSG ¼ .4%). Mean age and body mass index were 40 years (18–65) and 43.4 kg/m 2 (35–59.7), respectively. Abdominal pain was the most common (98%) presenting symptom. Of patients, 92% had a hematologic abnormality identified, and of these, FVIII elevation was the most common (76%). The vast majority (90%) was successfully managed with therapeutic anticoagulation alone. A smaller number of patients required small bowel resection (n ¼ 2) and surgical thrombectomy (n ¼ 1). There were no mortalities. Conclusions: A high index of clinical suspicion and prompt diagnosis/treatment of PMVT usually leads to favorable outcomes. FVIII elevation was the most common (76%) hematologic abnormality identified in this patient cohort. Further studies are needed to determine the prevalence of FVIII elevation in patients seeking bariatric surgery. (Surg Obes Relat Dis 2017;]:00–00.) r 2017 American Society for Metabolic and Bariatric Surgery. All rights reserved. http://dx.doi.org/10.1016/j.soard.2017.08.015 1550-7289/ r 2017 American Society for Metabolic and Bariatric Surgery. All rights reserved. * Correspondence: Manish Parikh, M.D., Department of Surgery, New York University Langone Medical Center, Bellevue Hospital Center, 550 First Avenue NB 15 South 7, New York, NY 10016. E-mail: manish.parikh@nyumc.org