Secondary Interventions After Iliac Vein Stenting for Chronic Proximal Venous Outflow Obstruction

Abstract

Iliac stent placement is an increasingly common procedure in the treatment of chronic proximal venous outflow obstruction (PVOO), but secondary interventions after vein stent placement remain poorly characterized. Our goals were to identify the incidence, indications, operative findings, and outcomes of secondary interventions after the primary iliac vein stent procedure in a single institution. We retrospectively reviewed the clinical history of 490 patients (42.41% male; mean age, 60.77 years [range, 18-92 years]; 93.28% follow-up with a mean follow-up of 308.59 days) who underwent iliac stent placement (Wallstent; Boston Scientific, Marlborough, Mass) for PVOO between October 2013 and June 2016. We specifically evaluated the clinical presentation, intraoperative findings, and outcomes among those patients who required a secondary intervention after an initial iliac vein stent procedure. Secondary interventions after an initial stent placement were identified in 50 of 490 patients (10.2%; mean age, 61.54 years [range, 19-92 years]; 58% female [n = 29]). Among these 50 patients, 56% (n = 28) of secondary interventions were due to recurrence of symptoms after the initial stent surgery, 24% (n = 12) were due to the development of new symptoms, and 20% (n = 10) were due to persistence of symptoms. Intraoperative findings during the secondary intervention included migration of the stent (8% [n = 4]), acute deep venous thrombosis/thrombosis (12% [n = 6]), an additional lesion (ie, stenosis in a native iliac vein proximal or distal to the original lesion; 50% [n = 25]), stenosis within the stent (stent stenosis without finding of thrombus or isolated, focal intrastent thrombosis; 16% [n = 8]), impairment of flow of the contralateral vessel from the previous stent (12% [n = 6]), and no finding (2% [n = 1]). The types of secondary interventions were placement of a new stent (80% [n = 40]), isolated balloon angioplasty alone (6% [n = 3]), and catheter PMT (14% [n = 7]). Significant symptomatic improvement was observed after the secondary intervention in 90% of patients (n = 45); 2% (n = 1) of patients experienced only a transient improvement, and 8% of patients (n = 4) reported no improvement in their symptoms. This study establishes a secondary intervention rate of 10% after iliac vein stent placement for chronic PVOO, identifies discrete and definable intraoperative findings as targets for quality improvement, and indicates that secondary interventions after vein stent placement are associated with a good outcome.