Recanalization of port-superior mesenteric vein thrombosis with long-term anticoagulant therapy after failed early anticoagulant therapy.

Background: Anticoagulant therapy with heparin is the first-line treatment for acute mesenteric vein thrombosis and is effective in improving outcomes. Conversely, patients with failed early anticoagulant therapy occasionally develop bowel infarction requiring surgery. The efficacy of long-term anticoagulant therapy on recanalizing mesenteric vein thrombosis in patients with failed early anticoagulant therapy remains unclear. Herein, we report a patient who achieved recanalization of port-superior mesenteric vein thrombosis treated with anticoagulant therapy for 10 years after failed early anticoagulant therapy, followed by bowel resection.

Case Presentation: A 38-year-old male patient visited an outpatient clinic due to acute exacerbation of abdominal pain that had persisted for a month. He was diagnosed with port-superior mesenteric vein thrombosis on contrast-enhanced computed tomography (CT) scan and was transferred to our institution. Although he presented with abdominal pain, his respiration and circulation were stable upon hospital arrival. Anticoagulant therapy with heparin was started, and the patient was admitted to the intensive care unit. However, the patient's abdominal pain worsened, and he began to develop signs of peritonitis. Repeat CT scan revealed bowel infarction. Thus, the patient underwent bowel resection 6 h after admission. The initial surgery was completed with open abdomen management. Bowel anastomosis was performed on the second-look surgery on the first postoperative day. Finally, the abdomen was closed on the third postoperative day after confirming the absence of bowel ischemia progression. The patient had prolonged impaired bowel function with paralytic ileus, but was discharged on the 60th postoperative day. He was then diagnosed with protein C and S deficiency based on the tests performed. Anticoagulant therapy with warfarin was initiated. He also received anticoagulant therapy in the outpatient setting. The patient's port-superior mesenteric vein thrombosis had improved gradually with warfarin during the follow-up period. At 10 years after surgery, total occlusion of the port-superior mesenteric vein was recanalized with improvement of the portal collateral vessels. In addition, no gastric or esophageal varices were observed.

Conclusions: Long-term anticoagulation therapy could affect the recanalization of extensive thrombus in multiple segments in patients with mesenteric venous thrombosis.