Iliac vein stenting is safe when performed in an office based laboratory setting.

BACKGROUND: Venous stenting for iliac vein outflow obstruction is associated with excellent long-term stent patency and symptom resolution. However, the safety of iliac vein stenting performed in an office-based laboratory (OBL) setting is not well-defined. The purpose of our investigation was to determine the safety profile of iliac vein stenting in an OBL setting. METHODS: Data were prospectively collected in the Center for Vascular Medicine electronic medical record system (NextGen Healthcare Information System, Irvine, Calif) and retrospectively analyzed. Standardized patient safety and sedation protocols were used in accordance with the accreditation standards of the Joint Commission for Accreditation of Hospital Organizations for office-based surgery centers. Patient consultations, interventions, and follow-up at 1 to 6 weeks were included in the present analysis. All the patients had received moderate sedation during their procedure. Complications requiring hospitalization were classified as major complications. Minor complications consisted of bleeding, hematoma, vasovagal response, in-stent thrombosis resulting in complete occlusion of the iliac vein stent, an allergic reaction, hematemesis, hypotension, pelvic discomfort, and pseudoaneurysm. RESULTS: Between January 2015 and January 2019, 1223 iliac vein stents were placed in 1104 patients (23.7% male; 76.3% female). A total of 90 minor complications (7.36%) and 5 major complications (0.41%) were observed. The major complications included the following: one allergic reaction, one episode of atrial fibrillation, one episode of supraventricular tachycardia, one episode of chest pain, and one case of acute stent occlusion. The minor complications were primarily insertion site hematomas. No complications were related to sedation or acute renal failure. No patient died. CONCLUSIONS: Major complications were rare after iliac vein stenting in an OBL setting. Minor complications were primarily insertion site hematomas, which did not require inpatient hospitalization. Our analysis has shown that iliac vein stenting in an OBL setting is a safe and well-tolerated procedure.

Type of anti-thrombotic therapy for venous stenting in patients with non-thrombotic iliac vein lesions does not influence the development of in-stent restenosis.

BACKGROUND: In patients receiving stents for symptomatic non-thrombotic iliac vein lesions, many clinicians prescribe anti-thrombotic medications. Whether or not anti-coagulation post-venous stenting improves stent patency is unknown. The aim of this investigation is to determine whether prophylactic post-operative anti-thrombotic therapy improves stent patency and/or prevents in-stent restenosis. METHODS: The medical records and venous ultrasounds for 389 patients stented for non-thrombotic iliac vein lesions were retrospectively reviewed. Patients were categorized into three anti-thrombotic regimens: Clopidogrel, Aspirin and Clopidogrel, and Apixaban or Rivaroxaban. Patients were routinely assessed for restenosis and stent patency at 6, 26, and 52 weeks and treated with anti-thrombotics for 90 days. RESULTS: Freedom from in-stent restenosis at 6, 26, and 52 weeks were Clopidogrel (91.50, 82.91, 80.95%), Aspirin and Clopidogrel (88.68, 80.03, 80.03%), and Apixaban or Rivaroxaban (91.03, 85.11, 83.18%). Primary patencies were Clopidogrel (98.77, 98.77, 98.10%), Aspirin and Clopidogrel (100, 95.74, 95.74%), and Apixaban or Rivaroxaban (98.70, 98.70, 96.71%). There were no statistically significant differences. CONCLUSIONS: The type of post-operative anti-thrombotic therapy for non-thrombotic iliac vein lesions does not appear to improve stent patency or prevent the development of in-stent restenosis.

Spine stabilization is a risk factor for the development of pelvic iliac vein lesions.

BACKGROUND: Open lumbar spine stabilization surgery often requires mobilization of the left and right common iliac veins (CIVs) and the placement of plates and screws that can impinge on them. We reviewed our venography experience of the past 3 years to determine whether there is an association between spine stabilization surgery and the development of symptomatic iliac vein outflow lesions. METHODS: A retrospective chart review of prospectively collected data from our electronic medical record system was performed to identify patients who underwent venography with or without venous stenting and had a history of previous lumbar spine stabilization. Patients' demographics, medical comorbidities, venograms, and intravascular ultrasound (IVUS) data were collected and analyzed. The senior author reviewed all venograms and IVUS images of patients with previous spine stabilization procedures. RESULTS: From January 2014 to April 2018, venography was performed in 1713 limbs in 1245 patients at the Center for Vascular Medicine. Of the 1245 patients, 18 patients had a history of lumbar spine stabilization procedures: five anterior-posterior and 13 posterior. Nine had single-level and eight had two- or three-level fusions. All 18 patients demonstrated pelvic lesions. These included 1 left CIV aneurysm, 5 left CIV stenoses, 3 bilateral CIV stenoses, 2 left CIV and inferior vena cava occlusions, and 2 external iliac vein stenoses. The aneurysm patient was treated with anticoagulation, 8 patients underwent stenting, 1 patient refused stenting because of relocation to another country, 1 inferior vena cava-CIV occlusion could not be crossed, fear of dislodging a thrombus and the proximity to a protruding posteriorly placed screw prevented stenting in 2 patients, and 4 patients had a venoplasty alone because of undersizing of a stenosis or missed lesions with IVUS after review by a blinded reviewer. Lesions in anterior lumbar interbody fusion patients were extremely stenotic, required predilation, and resulted in a residual stenosis requiring venoplasty at a second setting in one patient. CONCLUSIONS: Lumbar spine stabilization surgery may be a risk factor for development of symptomatic venous outflow obstruction lesions. During venography and stenting in patients with anterior lumbar interbody fusion approaches, significant scarring may be encountered, resulting in a residual stenosis after stent placement. Predilation venoplasty, before stent deployment, is recommended to prevent stent migration. Furthermore, a history of spine stabilization surgery in patients presenting with pelvic symptoms, lower extremity pain or swelling, or post-thrombotic symptoms should prompt consideration of a pelvic venous duplex ultrasound examination to determine whether an iliac venous outflow lesion is present.

Iliac vein stenosis is an underdiagnosed cause of pelvic venous insufficiency.

BACKGROUND: Reflux in the ovarian veins, with or without an obstructive venous outflow component, is reported to be the primary cause of pelvic venous insufficiency (PVI). The degree to which venous outflow obstruction plays a role in PVI is currently ill-defined. METHODS: We retrospectively reviewed the charts of 227 women with PVI who presented to the Center for Vascular Medicine from January 2012 to September 2015. Assessments and interventions consisted of an evaluation for other causes of chronic pelvic pain by a gynecologist; preintervention and postintervention visual analog scale (VAS) pain score; complete venous duplex ultrasound examination; and Clinical, Etiology, Anatomy, and Pathophysiology classification. All patients underwent diagnostic venography of their pelvic and left ovarian veins as well as intravascular ultrasound of their iliac veins. Patients were treated in one of six ways: ovarian vein embolization (OVE) alone (chemical ± coils), OVE with staged iliac vein stenting, OVE with simultaneous iliac vein stenting, iliac vein stenting alone, OVE with venoplasty, and venoplasty alone. RESULTS: Of the 227 women treated, the average age and number of pregnancies was 46.4 ± 10.4 years and 3.36 ± 1.99, respectively. Treatment distribution was the following: OVE, n = 39; OVE with staged stenting, n = 94; OVE with simultaneous stenting, n = 33; stenting alone, n = 50; OVE with venoplasty, n = 8; and venoplasty alone, n = 3. Seven patients in the OVE and stenting groups (staged) and one patient in the OVE + venoplasty group required a second embolization of the left ovarian vein. Eighty percent (181/227) of patients demonstrated an iliac stenosis >50% by intravascular ultrasound. Average VAS scores for the entire cohort before and after intervention were 8.45 ± 1.11 and 1.86 ± 1.61 (P ≤ .001). In the staged group, only 9 of 94 patients reported a decrease in the VAS score with OVE alone. VAS score decreased from 8.6 ± 0.89 before OVE to 7.97 ± 2.10 after OVE. After the planned staged stenting, VAS score decreased to 1.33 ± 2.33 (P ≤ .001). Similarly, in the simultaneous group, preintervention scores were 8.63 ± 1.07 and decreased to 2.36 ± 2.67 after OVE + stenting (P ≤ .001). CONCLUSIONS: The majority of patients in our series (80%) demonstrated a significant iliac vein stenosis. These observations indicate that the incidence of iliac vein outflow obstruction in PVI is greater than previously reported. In patients with combined ovarian vein reflux and iliac vein outflow obstruction, our data suggest that pelvic venous outflow lesions should be treated first and that ovarian vein reflux should be treated only if symptoms persist. In women with an outflow lesion, ovarian vein reflux, and a large pelvic reservoir, we recommend simultaneous treatment.