3:18 PM Abstract No. 53 Changes in two-dimensional perfusion angiography before and after inferior vena cava filter retrieval

Abstract

To investigate differences in hemodynamic flow parameters acquired in two-dimension (2D) perfusion angiography before and after inferior vena cava (IVC) filter retrieval. IVC filter retrievals at a single institution were retrospectively reviewed. Standardized breath-hold, digital subtraction angiography was performed at 2-3 frames per second before and after removal, and 2D-perfusion images were reconstructed on a dedicated workstation (Philips Allura Xper FD20, Philips Medical Systems, Best, Netherlands). Changes in the density per pixel per second within a region of interest (ROI) were used to calculate contrast arrival time, time-to-peak (TTP), wash-in-rate (WIR), area under the curve (AUC), and mean transit time (MTT). Measurements were obtained inferior, superior, and at the level of the filter. Differences in the hemodynamic parameters before and after filter removal were assessed with Mann-Whitney U analysis. A p-value of <0.05 was considered statistically significant. At the level of the filter, the TTP was significantly longer before filter removal when compared to after, with mean times of 1.28 and 0.78 seconds, respectively (p = 0.042). The MTT inferior to the filter was longer before filter removal when compared to after, with mean times of 0.8 and 0.5 seconds, respectively. The WIR inferior to the filter was longer before filter removal when compared to after, with mean of 435 and 250 HU/second, respectively. Preliminary data evaluating differences in flow parameters acquired in 2D-perfusion angiography before and after IVC filter retrieval demonstrate a significantly longer TTP when filters are in place, suggesting a functional hemodynamic delay secondary to filter presence.