Prevention of pulmonary embolisms associated with vena cava filter implantation.

Objective: To investigate the prevention of pulmonary embolism (PE) by the implantation of inferior vena cava filters (IVCFs).

Methods: Data of 1058 patients treated for lower extremity deep vein thrombosis (DVT) between January 2005 and January 2012 were analyzed retrospectively and divided into those with and without PE.

Results: Of the 1058 patients, 34 had PEs (3.2%) and 1024 did not. Multivariable analyses showed that PEs were less likely to occur in patients with IVCFs than in those without IVCFs (odd ratio [OR] =  0.028, P < 0.001), and were more likely to occur in patients with vena cava thrombosis than in those without vena cava thrombosis (OR =  19.094, P < 0.001). Analyses stratified by DVT site showed that vena cava thrombosis was the only risk factor of PE for patients with a left DVT (crude OR =  12.814, P < 0.001), and IVCF implantation was the only protective factor for PE for patients with a right or bilateral DVT (crude OR =  0.028, P =  0.001). IVCF patency rate for follow-up was 98.7% with no filter migration, declination, or failure of expansion.

Conclusions: IVCFs can reduce the occurrence of PEs in patients with DVTs.