Use of a Retrievable Vena Cava Filter with Low-intensity Anticoagulation for Prevention of Pulmonary Embolism in Patients with Cancer: An Observational Study in 106 Cases

Purpose: To evaluate a retrievable inferior vena cava (IVC) filter in combination with low-intensity oral anticoagulation for prevention of pulmonary embolism (PE) in patients with malignancy complicated by thromboembolic disease. Materials and Methods: From October 2005 to December 2009, 107 Bard G2 filters were placed in 106 patients. Forty-eight patients had deep vein thrombosis (DVT) alone, 53 had PE with DVT, and five had PE with no evidence of DVT. After an initial period of anticoagulation with heparin, low-intensity oral anticoagulant therapy to achieve a target International Normalized Ratio of 1.5-2.0 was instituted. Follow-up computed tomography to evaluate the pulmonary circulation, IVC, and lower limbs was performed at 3 and 6 months. Results: PE recurred in three of 58 patients (5.2%). None of the 48 patients with DVT alone developed PE, nor was there any recurrence of DVT. The filter was removed in 14 patients (13.2%). No complications occurred during the retrieval procedure. A total of 16 complications occurred in seven patients: one migration (0.9%); four cases of vena cava thrombosis (3.7%), three of which were associated with recurrent PE (2.8%); one filter fracture (0.9%); and one IVC penetration (0.9%). Filter tilting greater than 15 occurred in six patients (5.7%) and was associated with other complications in five (4.7%). Conclusions: In patients with malignancies complicated by venous thromboembolic disease, an IVC filter together with low-intensity anticoagulation may be a possible treatment strategy for PE prophylaxis. Controlled studies are warranted.