Acute Venous Thromboembolism Is Common Following Acute Necrotizing Pancreatitis and Is Associated With Worse Clinical Outcomes.

Objectives: Although splanchnic vein thrombosis (SVT) is a well-known local complication of acute pancreatitis, extrasplanchnic venous thromboembolism (ESVT) is inadequately studied. Here, we aim to explore the incidence of venous thromboembolism (VTE) in acute necrotizing pancreatitis (ANP) and the associated mortality.

Methods: Adults with a diagnosis of ANP from January 2017 to December 2022 were identified using appropriate International Classification of Diseases, 10th Revision, Clinical Modification codes. The primary outcome was development of acute ESVT within 1 month of ANP. Secondary outcomes were 90-day mortality, 30-day rehospitalization, and oral anticoagulant (OAC) use in patients with ESVT. Propensity score matching (1:1) was performed for baseline characteristics and common comorbidities.

Results: During the study period, 17,942 (7.11%) patients were diagnosed with ANP, and about 10% (1,737) of them had a diagnosis of ESVT. Of all VTEs, 61% were ESVT with or without SVT, and 63% (n = 1799) were SVT. Ninety-day mortality (16.3% vs 5.7%; risk ratio [RR], 2.86; 95% confidence interval, 2.29-3.56) and 30-day rehospitalization (31% vs 19%; RR, 1.63; 95% confidence interval, 1.49-1.79) were higher in patients with ESVT compared with non-VTE patients. Sixty percent of patients with ESVT were on OAC, and OAC use was associated with lower 90-day mortality (8.9% vs 19.4%; RR, 0.46) without increased risk of adverse events (acute gastrointestinal bleeding, intracranial bleeding, or need for transfusion).

Conclusions: Systemic VTE is common in patients with ANP and may contribute to increased mortality and risk of readmissions. Prospective studies can confirm our findings and explore the role of aggressive VTE prophylaxis in patients with ANP during hospital stay and in the immediate ambulatory period.