Treatment outcomes and risk factors for bowel infarction in patients with acute superior mesenteric venous thrombosis.

OBJECTIVE

The prognosis of acute superior mesenteric venous thrombosis (SMVT) remains obscure. We aimed to investigate the treatment outcomes and possible risk factors for bowel infarction in these patients.

METHODS

We retrospectively included 66 patients with acute SMVT between January 2002 and June 2016. Each patient underwent contrast-enhanced computed tomography as part of the initial diagnosis. The standard protocol for management included a nonsurgical approach with early anticoagulation and selective exploration. For the analysis of the risk factors for bowel infarction, patients were divided into bowel resection (BR) and non-BR groups. Outcomes of interest were causes of SMVT, percentage of BR after nonsurgical treatment, and risk factors for BR.

RESULTS

Of 66 patients, 15 (23%) underwent BR; of these, 9 underwent urgent BR because of peritoneal signs and definite findings of bowel infarction on computed tomography scan, 4 underwent BR after failed anticoagulation, and 2 underwent BR because of delayed stricture. Clinically, vomiting (P = .003), abdominal distention (P = .003), rebound tenderness (P = .005), and leukocytosis (P = .001) were associated with BR. On radiologic examination, bowel wall thickening (P < .001), enhancement defects of the bowel wall (P < .001), and ascites (P = .007) were associated with BR. Twenty-seven (41%) patients presented with isolated SMVT, and the remaining patients demonstrated a coexisting portal vein (PV) thrombosis in addition to SMVT. All 15 BRs occurred in patients with combined PV thrombosis and SMVT (P < .001). Complete thrombosis of the superior mesenteric vein and PV was also associated with BR (P = .028 for superior mesenteric vein; P = .025 for PV). BR was performed in 1 (4%) of 24 patients with transient risk factors compared with 14 (33%) of 42 patients without transient risk factors (P = .006). Three patients (4.5%) died in the hospital.

CONCLUSIONS

In patients with acute SMVT, the extent of thrombus and etiology were associated with the severity of acute SMVT. Patients with transient risk factors and isolated SMVT tended to have a benign disease course. With early anticoagulation, acute SMVT does not seem to have the grave prognosis that is associated with arterial thrombosis.