Management strategies and clinical outcomes in patients with inferior vena cava thrombosis: Data from GARFIELD-VTE

Background: Inferior vena cava (IVC) thrombosis is a rare form of venous thromboembolism (VTE). The optimal treatment strategies and outcomes are unclear in patients with this presentation. Objective: We aimed to compare baseline characteristics, treatment patterns and 24-month outcomes in IVC thrombosis patients (n=100) with lower extremity deep vein thrombosis (LEDVT) patients (n=7629). Methods: GARFIELD–VTE is a prospective, observational registry of 10868 patients with objectively diagnosed VTE from 415sites in 28 countries. Results: IVC thrombosis patients were younger (51.9 vs. 59.8years), more frequently had active cancer (26.0% vs. 8.9%) or history of cancer (21.0% vs. 12.2%), and less frequently had recent trauma or surgery than LEDVT patients. IVC thrombosis was more frequently treated with parenteral anticoagulants alone (35.1% vs. 15.9%), whereas patients with LEDVT more commonly received vitamin K antagonists (32.0% vs. 25.8%) or direct oral anticoagulants (49.0% vs. 35.1%). Thrombolysis (11.0% vs. 3.6%) and surgical/mechanical interventions (4.0% vs. 1.4%) were more frequent in IVC thrombosis. At 24-months, the rate per 100 person-years (95% confidence interval) of all-cause mortality was higher in patients with IVC thrombosis than LEDVT (13.28 [8.57–20.58] vs. 4.91 [4.55–5.3]); the incidence of cancer-associated mortality was comparable as was the incidence of VTE recurrence (4.11 [1.85–9.15] vs. 4.18 [3.84–4.55]). Major bleeding was slightly higher in IVC thrombosis (2.03 [0.66–6.31] vs. 1.66 [1.45–1.89]). Conclusion: In summary, IVC thrombosis patients have higher all-cause mortality rates than those with LEDVT, a finding only partly attributable to malignancy.