Effect of Etiology and Inflow on Outcomes of Endovascular Recanalization for Nonmalignant Inferior Vena Cava Occlusion

Abstract

The aim of this study was to determine factors affecting outcomes of inferior vena cava (IVC) recanalization for nonmalignant obstruction, with focus on venous inflow and etiology of IVC occlusion. Data from consecutive patients undergoing IVC recanalization between January 2001 and December 2017 were retrospectively reviewed. Patients were grouped by etiology of IVC obstruction, including post-thrombotic (PT), retroperitoneal fibrosis (RPF), and hypoplasia (HP). Patency of the femoral, deep femoral, and great saphenous veins was evaluated; the venous inflow was graded, assigning a point to each for stenosis or occlusion, for a total possible unilateral score of 3 and a composite score of 6. A score of 6 indicated no inflow stenosis or occlusion, whereas a score of 0 indicated disease of all 6 inflow veins. Primary outcomes included primary, primary assisted, and secondary patency rates. There were 114 patients during the 18-year period (64% male; mean age, 42 ± 15 years). Etiology was PT in 96 (84%), RPF in 5 (5%), and HP in 13 (11%) patients. Clinical, Etiology, Anatomy, and Pathophysiology classes included 3, 4a, 4b, 5, and 6 in 23, 17, 3, 11, and 23 patients, respectively. Forty-four (38%) patients had an IVC filter, all of whom had PT etiology, and 33 (29%) had a thrombophilia. Inflow grading was 6 in 20 (18%), indicating no disease; 4 in 36 (32%); and 3 or less in 32 (30%). There was no mortality related to the procedure. Periprocedural complications occurred in 11% of patients. Median follow-up was 15.2 months (interquartile range, 6.4-35.8 months; maximum, 141.6 months). Kaplan-Meier analysis of primary, primary assisted, and secondary patency in the entire cohort at 1 year and 5 years was 78%, 85%, and 95% and 66%, 85%, and 95%, respectively. Early failures occurred in 12 PT, 2 HP, and 0 RPF patients (P = .94) No factors studied, including female sex, etiology of IVC occlusion, or thrombophilia, affected patency (P > .05). Median venous inflow in PT, RPF, and HP was 4, 5.5, and 5, respectively. Patients with grade 0 to 3 had patency rates similar to those of patients with grade 4 to 6 (P > .05). Presence of an IVC filter crushed aside during IVC stenting did not adversely affect stent patency. Midterm results of endovascular recanalization are excellent regardless of the etiology of IVC occlusion. This cohort was predominantly PT with small numbers of RPF and HP, resulting in insufficient statistical power to demonstrate the effect of venous inflow on patency.