OBJECTIVETo discuss the efficacy of anticoagulation on patency post-permanent inferior vena caval filter (IVCF) placements.

METHODSThe patients with deep vein thrombosis (DVT) of the lower extremity who were accepted permanent IVCF placement from December 2001 to December 2007 were reviewed retrospectively. Data on vital status, filter thromboembolism, anticoagulation time, and so on were obtained through follow-up. One hundred and thirty eight patients (75 male and 63 female) with a mean age of 65 years were enrolled in the study. All the patients were divided into non-anticoagulation group, anticoagulation group A with taking warfarin less than 6 months, or anticoagulation group B with taking warfarin more than 6 months. chi(2) test, t test, Kaplan-Meier survival curve, Log-rank test were used for statistics analysis.

RESULTSSixteen patients died, and 1 of them died of pulmonary embolism. Including the 1 patient mentioned before, there were 19 patients (13.8%) suffered from filter thromboembolism. Upon chi(2) test, there were no significant differences (P = 0.288) on the patency rates between non-anticoagulation, anticoagulation group A and anticoagulation group B (87.8%, 75.0%, and 88.3% respectively). Upon Kaplan-Meier survival analysis, there were still no significant differences (P = 0.227) on the mean patency time and the cumulate rates of patency at the 1st or 3rd year between the 3 groups (87.1%, 80.0%, 94.8% and 87.1%, 74.3%, 85.4% respectively).

CONCLUSIONAnticoagulation has no efficacy on patency post-permanent IVCF placements.