Abstract No. 67: Effect of Thrombophilia on IVC Filter Function: Complications and Efficacy in Cancer vs Non Cancer Patients

Abstract

Prudent IVC filter placement hinges upon balancing possible complications versus pulmonary embolism protection for appropriate indications. Cancer patients have inherent thrombophilia, yet frequently IVC filters are placed with a paucity of conclusive evidence that the benefits outweigh the risks. In our study, we sought to compare the efficacy of PE prevention and filter complications in cancer patients versus non cancer patients who received IVC filters. Between 2002 and 2006, 702 patients had IVC filters placed in our institution. The cohort was divided into 220 patients (31.3%) with cancer (CA) and 482 non cancer (NC) (68.7%). Charts of these patients were retrospectively analyzed with regard to demographics, indication for filter placement, filter types, and complications. Demographic features for CA and NC groups were: mean age 61.7yrs vs 55.4 (p <.0001), 44.5% women vs 47.7% (p = 0.44). Significantly more CA patients received filters due to contraindications to anticoagulation (AC) and fewer CA received filters for prophylactic reasons (p = 0.024). Significantly more CA patients had permanent filters placed compared with NC patients (p < 0.0001). CA vs NC patients were equally likely to present with DVT (p = 0.852) but were more likely to present with PE (p < 0.001) and IVC thrombus (p = 0.043). After filter placement, no significant differences were noted between the proportions of patients who got DVT (p = 0.56) and PE (p = 0.61) however the percent of IVC thrombosis was noted to be significantly higher for CA patients (1.8% versus 0.2%, p = 0.019). Mean follow up was 355 days for CA and 246 days for CF patients (p < 0.0001). Despite inherent thrombophilia in cancer patients, IVC filters offer comparable levels of protection from pulmonary embolism versus non-cancer patients but with higher rates of symptomatic IVC thrombosis. The low complication risk in cancer patients suggests an acceptable risk benefit ratio for placement in this high risk group.