Portomesentric and splenic vein thrombosis (PMSVT) after bariatric surgery: a systematic review of 110 patients.

Background: Portomesenteric and splenic vein thrombosis (PMSVT) is a rare but potentially serious complication after bariatric surgery. No study has systematically analyzed its incidence and risk factors.

Objectives: To pool the data regarding PMSVT after bariatric surgery and determine its incidence and risk factors.

Methods: A meta-analysis and systematic review was conducted to retrieve studies on PMSVT after bariatric surgery.

Results: A total of 41 eligible studies including 110 patients with postbariatric PMSVT were enrolled; the estimated incidence rate based on 13 studies was .4%. The use of oral contraception was reported in 35.4% of patients, previous surgery in 61.1%, smoking in 37.2%, and history of coagulopathy in 43%. PMSVT mostly occurred after sleeve gastrectomy (78.9%) and within the first postoperative month (88.9%). Pneumoperitoneum pressure was>15 mm Hg in 6% of patients. The portal vein was the most commonly affected vessel (41.5%). Prothrombin 20210 mutation and protein C/S deficiency were the most common thrombophilic conditions. Unfractionated heparin (59.1%), vitamin K antagonists (50.9%), and low molecular weight heparin (39.1%) were the most common treatments for PMSVT. The morbidity and mortality rates for postbariatric PMSVT were 8.2% and 3.6%, respectively.

Conclusion: PMSVT usually occurs within the first postoperative month and is mostly reported after sleeve gastrectomy. The portal vein is the most commonly involved vessel. A previous hypercoagulable state can be an important risk factor. Most patients can be treated with anticoagulation therapy. Further studies with comprehensive data review of patient information are required.