Double-Barrel Nitinol Stent Placement for Iliocaval Reconstruction: The Effect of Deployment Sequence and Direction on Final Configuration

Double-barrel stent placement across the iliocaval confluence is commonly used for the treatment of chronic bilateral iliocaval occlusion. The difference in the deployment outcomes of synchronous parallel stent deployment versus asynchronous or antiparallel deployment and the underlying stent interactions are poorly understood. In this study, 3 strategies of double-barrel nitinol self-expanding stent deployment across the iliocaval confluence (synchronous parallel, asynchronous parallel, and synchronous antiparallel) were contrasted in vivo in 3 swine followed by assessment of the explanted stent construct. Synchronous parallel stent deployment achieved a desired double-barrel configuration. The asynchronous parallel and antiparallel deployment strategies both resulted in a crushed stent despite subsequent simultaneous balloon angioplasty. These animal model results suggested that in patients who undergo double-barrel iliocaval reconstruction, synchronous parallel stent deployment may provide the desired stent conformation and increase the chance for clinical success.     

Lower Extremity Venous Stent Placement: A Large Retrospective Single-Center Analysis

PurposeTo study short-term and long-term outcomes of lower extremity venous stents placed at a single center and to characterize changes in vein diameter achieved by stent placement.Materials and MethodsA database of all patients who received lower extremity venous stents between 1996 and 2018 revealed 1,094 stents were placed in 406 patients (172 men, 234 women; median age, 49 y) in 513 limbs, including patients with iliocaval stents (9.4% acute thrombosis, 65.3% chronic thrombosis, 25.3% nonthrombotic lesions). Primary, primary assisted, and secondary patency rates were assessed for lower extremity venous stents at 1, 3, and 5 years using Kaplan-Meier analyses and summary statistics. Subset analyses and Cox regression were performed to identify risk factors for patency loss. Vein diameters and Villalta scores before and up to 12 months after stent placement were compared. Complication and mortality rates were calculated.ResultsPrimary, primary assisted, and secondary patency rates at 5 years were 57.3%, 77.2%, and 80.9% by Kaplan-Meier methods and 78.6%, 90.3%, and 92.8% by summary statistics. Median follow-up was 199 days (interquartile range, 35.2–712.0 d). Patency rates for the subset of patients (n = 46) with ≥ 5 years of follow-up (mean ± SD 9.1 y ± 3.4) were nearly identical to cohort patency rates at 5 years. Patients with inferior vena cava stent placement (hazard ratio 2.11, P < .0001) or acute thrombosis (hazard ratio 3.65, P < .0001) during the index procedure had significantly increased risk of losing primary patency status. Vein diameters were significantly greater after stent placement. There were no instances of stent fracture, migration, or structural deformities. In patients with chronic deep vein thrombosis, Villalta scores significantly decreased after stent placement (from 15.7 to 7.4, P < .0001). Perioperative mortality was < 1%, and major perioperative complication rate was 3.7%.ConclusionsCavo-ilio-femoral stent placement for venous occlusive disease achieves improvement of vein disease severity scores, increase in treated vein diameters, and satisfactory long-term patency rates.     

Five-Year Outcomes of the Bioresorbable Peripheral Remedy Stent in the Treatment of Iliac Artery Disease

PurposeTo evaluate the 5-year performance of a bioresorbable vascular scaffold, the Remedy stent, for the treatment of iliac artery atherosclerotic disease.Materials and MethodsThis prospective, multicenter, single-arm clinical study evaluated 97 patients (97 lesions) with symptomatic TransAtlantic Inter-Society Consensus II A/B iliac artery lesions for 5 years after stent placement. The primary efficacy end point was 12-month primary patency compared with the prespecified standard derived from historical data with metallic stents, and the primary safety end point was the occurrence of major adverse clinical events within 5 years. All angiographic and computed tomography angiographic findings were evaluated by an independent core laboratory for quantitative vessel analysis.ResultsThe 12-month primary patency rate was 88.6% (95% CI, 80.1%–94.4%), which was lower than the prespecified standard. No significant difference was noted between the diameter stenosis at 9 and 12 months. There were no device- or procedure-related deaths, major amputation, or distal embolization during the follow-up period. The ankle-brachial index maintained significant improvement through the 5-year period compared with that at baseline. The Kaplan–Meier estimates of freedom from target lesion revascularization (TLR), major adverse cardiovascular events, and major adverse cardiovascular and limb events were 95.8%, 91.7%, and 87.5% at 12 months and 85.4%, 72.1%, and 62.5% at 5 years, respectively.ConclusionsThe 5-year follow-up outcomes, including freedom from TLR, of the Remedy stent in iliac artery lesions were satisfactory, with a good safety profile. Nevertheless, the 12-month primary patency did not meet the expected standard compared with that of contemporary metallic stents.     

No Advantage of Expanded Polytetrafluoroethylene and Fluorinated Ethylene Propylene–Covered Stents over Uncovered Nitinol Stents for Percutaneous Palliation of Malignant Infrahilar Biliary Obstruction: Results of a Single-Center Prospective Randomized Trial

PurposeTo prove that covered stents are more efficacious than uncovered stents regarding patency, safety, enabling of chemotherapy, and survival in percutaneous palliation of malignant infrahilar biliary obstruction.Materials and MethodsAfter failed endoscopic treatment, 154 patients with obstructive jaundice caused by unresectable infrahilar malignancy were randomly allocated to receive an expanded polytetrafluoroethylene and fluorinated ethylene propylene–covered or an uncovered nitinol stent. Occlusion rate, patency, and survival were assessed. Safety and clinical success in terms of chemotherapy were compared.ResultsThree patients were excluded post hoc. Fifteen patients died within 7 d and were excluded from patency analysis. Occlusion rates were 32% (21 of 66) for covered and 29% (20 of 70) for uncovered stents (P = .7). Estimated median patency durations were 308 d (95% confidence interval [CI], 178–438 d) for covered and 442 d (95% CI, 172–712 d) for uncovered stents (P = .1). Serious adverse events (P = 1.0) and 30-day mortality (P = .5) were equivalent between groups. At hospital discharge, median bilirubin reduction of 8 mg/dL was found in both groups (P < .001). In the covered stent group, 35 patients (48%) received palliative chemotherapy, vs 29 (37%) in the uncovered stent group (P = .2). Estimated median survival times were 96 days (95% CI, 68–124 d) with covered stents and 75 days (95% CI, 42–108 d) with uncovered stents (P = .6).ConclusionsIn malignant infrahilar biliary obstruction not amenable to endoscopy, no improvement in patency or survival with percutaneously placed covered stents could be confirmed. Covered and uncovered stent types exhibit similar safety profiles and clinical success rates.     

Endovascular Treatment of Malignant Superior Vena Cava Syndrome through Upper-Limb Access: A Comparison between Venous-Dedicated and Conventional Stents

PurposeTo retrospectively evaluate the technical and clinical outcomes of superior vena cava (SVC) stent placement through upper-limb venous access in malignant SVC syndrome (SVCS) and compare the efficacy of different nitinol stent types.Materials and MethodsBetween 2006 and 2018, 156 patients (132 male; mean age, 62 y; age range, 33–81 y) underwent SVC stent placement for malignant obstructions through upper-limb venous access with 1 of 3 types of nitinol stent: 1 venous-dedicated (Sinus-XL stent) and 2 non–venous-dedicated (E-Luminexx Vascular Stent and Protégé GPS). Cases of common femoral vein access or non-nitinol stents were excluded from further analysis. The mean duration of follow-up was 8 mo.ResultsTechnical success was achieved in 99.3% of cases. One patient died during the procedure as a result of cardiac tamponade. Balloon predilation was performed in 10 patients and postdilation in 126. Mean procedural time was 34.4 min (range, 18–80 min). Overall survival rates were 92.3%, 57.3%, and 26.8%, and overall primary patency rates were 94.5%, 84.8% and 79.6%, at 1, 6, and 12 mo, respectively. There were no statistically significant differences in primary patency rates between venous- and non–venous-dedicated stents or among different Stanford SVCS grading groups (P > .05).ConclusionsSVC stent placement through an upper-limb approach is a safe, fast, and effective technique. There is no evident benefit of venous-dedicated vs non–venous-dedicated stents in the treatment of malignant SVCS.     

Single-Session Treatment of Patients with Symptomatic Iliocaval and Iliofemoral Deep Vein Thrombosis: Technical Results of a Prospective Pilot Study

PurposeTo investigate the short-term results of single-session treatment of iliocaval and iliofemoral DVT using a single thrombectomy device.Materials and MethodsThis prospective pilot study analyzed patients with acute iliocaval or iliofemoral DVT treated in a single session using the JETi thrombectomy system. All analyses were performed on an intention-to-treat basis. The cohort consisted of 53 limbs in 47 patients (27 women), with a mean age of 57 years (range, 16–88 years). The primary safety and efficacy endpoints were freedom from major adverse events (MAEs) and reestablishment of unobstructed flow in a single session, respectively.ResultsThe mean duration of symptoms was 8.5 days ± SD 9.2, with 10 patients (11 limbs, 21.3%) presenting with a symptom duration of >14 days. Twelve (25.5%) patients had thrombosis of the inferior vena cava and the iliofemoral segments. During the index procedure, unobstructed flow was reestablished in 47 of 53 (88.6%) limbs in 41 of 47 (87.2%) patients (primary endpoint) with no MAEs through 30 days. Overall, unobstructed flow was restored in 50 of 53 (94.3%) limbs and in 44 of 47 (93.6%) patients.ConclusionsSuccessful single-session treatment of patients with acute iliocaval and iliofemoral DVT is feasible with a high rate of efficacy and a low rate of adverse events. Such patients may be treated on an outpatient basis.     

Midterm and Long-Term Outcomes following Dedicated Endovenous Nitinol Stent Placement for Symptomatic Iliofemoral Venous Obstruction: Three- to 5-Year Results of the VIRTUS Study

PurposeTo assess the midterm patency and long-term safety of placement of a dedicated venous stent (Vici Venous Stent System) for the treatment of venous lesions of the iliofemoral outflow tract.Materials and MethodsPatients with unilateral obstructive disease of the iliofemoral veins and a Clinical, Etiological, Anatomical, Pathophysiological class of 3 or higher or a Venous Clinical Severity Score of 2 or greater were enrolled in this prospective, multicenter, single-arm study at 23 sites in the United States and Europe. The patients were followed up for 36 months after the index procedure for the assessment of patency and up to 60 months for the assessment of safety. The clinical outcomes in 11 patients with a stent fracture were assessed.ResultsA total of 200 patients enrolled in 2 cohorts (ie, feasibility cohort, n = 30; pivotal cohort, n = 170) were combined for this analysis. The overall 36-month primary patency rate was 71.7% (86/120), and the 36-month primary patency rate was 96.4% (27/28) for the nonthrombotic group and 64.1% (59/92) for the postthrombotic group. The freedom from major adverse events was 81.2% (53/65) through 60 months. The 60-month Kaplan-Meier estimate of freedom from target vessel revascularization (TVR) was 84.3%. In 9 of the 11 patients who had a stent fracture (1 patient with nonthrombotic etiology and 10 patients with postthrombotic etiology) identified at 12 months, the stents extended into the common femoral vein. The TVR rates and clinical outcomes were similar between patients with and without a stent fracture.ConclusionsThe results of the VIRTUS study demonstrated good midterm patency and long-term safety following the placement of a dedicated venous stent for iliofemoral obstruction.     

Treatment of Arm Swelling in Hemodialysis Patients with Ipsilateral Arteriovenous Access and Central Vein Stenosis: Conversion to the Hemodialysis Reliable Outflow Graft versus Stent Deployment

PurposeTo compare outcomes after conversion of arteriovenous (AV) access to Hemodialysis Reliable Outflow (HeRO) graft vs stent deployment in patients with arm swelling owing to ipsilateral central vein stenosis.Materials and MethodsThis single-center retrospective study comprised 48 patients (19 men, mean age 58 y) with arm swelling ipsilateral to AV access and central vein stenosis over a 13-year period who had clinical follow-up and without prior central stents. Twenty-one patients underwent placement of a HeRO graft with anastomosis of the HeRO graft to the existing graft or fistula, and 27 patients underwent central venous stent deployment. Symptomatic improvement in arm swelling and access patency rates after intervention were ascertained from medical records.ResultsImprovement in swelling within 1 month after HeRO conversion and stent deployment was found in 95% and 89%, respectively (P = .62). Swelling eventually recurred in 16 patients (59%) treated with stents compared with 1 patient (5%) who underwent HeRO conversion (P < .001). Primary access patency was statistically significantly longer after HeRO conversions than stent deployments, with 6- and 12-month primary patency rates of 89% and 72% vs 47% and 11% (P < .001). HeRO conversions also resulted in longer 6- and 12-month secondary access patency rates (95% and 95% vs 79% and 58%, P = .006). Mean number of interventions per 1,000 access days to maintain secondary patency was 2.7 for the HeRO group vs 6.3 for the stent group.ConclusionsAlthough stent deployment and HeRO graft conversion are effective for alleviating arm swelling in the short term in patients receiving hemodialysis with clinically significant arm swelling and functioning AV access, the HeRO graft has more durable results.     

Vascular Pathology and Impact of Stent Eccentricity for Stent Restenosis in Femoropopliteal Endovascular Therapy

PurposeTo explore the clinical features associated with stent eccentricity and reveal the impact of stent eccentricity on the risk of 1-year restenosis after femoropopliteal stent implantation for symptomatic atherosclerotic peripheral artery disease (PAD).Materials and MethodsThe clinical database of a multicenter prospective study was used. It registered 2,018 limbs of 1,766 patients in whom intravascular ultrasound (IVUS)-supported femoropopliteal endovascular therapy (EVT) for symptomatic atherosclerotic PAD was planned from November 2015 to June 2017. The study included 1,233 limbs of 1,088 patients implanted with a bare nitinol stent, drug-eluting stent (DES), or stent graft and administered ≥2 antithrombotic drugs. The stent eccentricity was evaluated using IVUS, calculated as [(maximum diameter) / (minimum diameter) ? 1] at the cross-sectional segment with the lowest lumen area after stent implantation.ResultsChronic total occlusion and bilateral arterial calcification (peripheral artery calcification scoring system Grades 3 and 4) were positively associated with stent eccentricity, whereas renal failure while receiving dialysis, DES use, and stent graft use were negatively associated with stent eccentricity (all P < .05). Stent eccentricity was associated with an increased risk of 1-year restenosis (odds ratio [OR], 1.18; 95% CI, 1.01–1.37; P = .034). However, after adjustment for lesion severity and implanted stent types, the association was no longer significant (OR, 1.07; 95% CI, 0.91–1.24; P = .43).ConclusionsStent eccentricity was not significantly associated with the risk of 1-year restenosis after femoropopliteal EVT.     

Percutaneous Cystic Duct Interventions and Drain Internalization for Calculous Cholecystitis in Patients Ineligible for Surgery

PurposeTo evaluate the feasibility, effectiveness, and outcomes of percutaneous cholecystostomy drain internalization in patients with calculous cholecystitis who were not surgical candidates.Materials and MethodsPercutaneous cystic duct interventions were attempted in 17 patients (with the intent to place dual cholecystoduodenal stents) who were deemed unfit for surgery and had previously undergone percutaneous cholecystostomies for acute calculous cholecystitis. Baseline demographics, technical success, time from percutaneous cholecystostomy to internalization (dual cholecystoduodenal stent placement), stent patency duration, and adverse event rates were evaluated.ResultsFifteen (88%) of 17 procedures to cross the cystic duct were technically successful. Of these 17 patients, 13 (76%) underwent successful placement of dual cholecystoduodenal stents. Two of these 13 patients (who had successful dual cholecystoduodenal stent placement) needed repeat percutaneous cholecystostomy drains (1 patient had stent migration leading to recurrent cholecystitis, and the other had a perihepatic biloma). The 1-year patency rate was 77% (95% CI, 47%–100%).ConclusionsDual cholecystoduodenal stent placement in nonsurgical patients is a technically feasible treatment option with the goal to remove percutaneous cholecystostomy drains.     

Pelvic Venous Disorders in Women due to Pelvic Varices: Treatment by Embolization: Experience in 520 Patients

PurposeThe purpose of this study was to determine the efficacy and safety of embolization treatment in pelvic venous disorders in women refluxing in the ovarian and or internal iliac veins in women with chronic pelvic pain.Materials and MethodsA retrospective study conducted from January 2000 to June 2017 in 617 patients diagnosed with pelvic venous disorders (PeVDs) with a mean age of 43.2 ± 7.2 years were treated using an embolization procedure. A total of 520 were included, and 97 patients were excluded. The main inclusion criteria were PeVD symptoms for more than 6 months and transvaginal Doppler ultrasonography (TV-DUS) diagnosis of varicose veins in the pelvis with a diameter greater than 6 mm. The main objective was to embolize the 4 main pelvic venous plexi (ovarian and internal iliac veins) whenever possible. Follow-up was performed using clinical symptoms (visual analog scale) and TV-DUS at 1, 3, 6, and 12 months and then every year up to 5 years.ResultsThe technical success (embolization of the 4 main pelvic veins) was achieved in 84.4% of the patients. The average follow-up was 58.7 ± 5.7 months. The visual analog scale was improved from 7.63 ± 0.9 points pretreatment to 0.91 ± 1.5 at 5 years. A total of 26 patients (5%) presented with symptom recurrence and pelvic varicose veins. There were 57 minor complications (10.9%) and 11 major complications (2.1%), with 7 cases (1.34%) of device migration to the lung.ConclusionsThe embolization of pelvic varicose veins is a safe and effective procedure. The selection of the embolic agents and the number of veins needed to be treated.     

Covered Stents for Treatment of Visceral Artery Aneurysms: A Multicenter Study

PurposeTo evaluate the safety and efficacy of covered stents for treatment of visceral artery aneurysms (VAA).MethodsThis multicenter retrospective study included patients with VAAs who were treated with covered stents between January 2015 and December 2020. A total of 65 patients (mean age, 58 years; range, 27–89 years) with 70 VAAs (60 true aneurysms [86%], 10 pseudoaneurysms [14%]) were included. Of the 65, 48 patients (74%) were asymptomatic. Patient demographics, endovascular treatments, and follow-up results were analyzed.ResultsAll patients received covered stents. The mean diameter was 2.9 cm (range, 1.0–7.6 cm) for symptomatic aneurysms and 2.5 cm (range, 1.0–9.0 cm) for asymptomatic aneurysms. Of the asymptomatic aneurysms, 89% had a saccular shape. The mean distance between the ostium of the artery in which the aneurysm occurred and the aneurysm was 3.9 cm (median, 3.0 cm; range, 0.5–10 cm). Additional coil embolization was used in 7 aneurysms (10%). During the procedure, 68 (97%) aneurysms were completely excluded, while 2 (3%) had a Type Ib endoleak. After a mean follow-up of 20 months (range, 1–75 months), all patients were asymptomatic. Four endoleaks were recorded and left for close observation. Four stents (7%) had mild restenosis, while the rest of the stents were patent.ConclusionsPlacement of covered stents in patients with VAAs excluded aneurysms and maintained artery patency.     

Stent Graft Placement for the Treatment of Hepatic Artery Injury in Patients with Cancer: Primary Patency and Clinical Outcomes

PurposeTo evaluate the safety, primary patency, and clinical outcomes of hepatic artery stent graft (SG) placement for vascular injuries.Materials and MethodsPatients treated with hepatic arterial SG placement for vascular injuries between September 2018 and September 2021 were reviewed. Data on demographic characteristics, indication, stent graft characteristics, antiplatelet/anticoagulant use, clinical success rate, complications, and type of follow-up imaging were collected. Follow-up images were reviewed by 2 independent reviewers to assess primary patency. A time-to-event analysis was performed. The median duration of stent graft patency was estimated using Kaplan-Meier curves. A Cox proportional hazard model was used to evaluate factors related to stent graft patency.ResultsThirty-five patients were treated with hepatic arterial SG placement, 11 for postoperative bleeds and 24 for hepatic artery infusion pump catheter–related complications. Clinical success was achieved in 32 (91%) patients (95% CI, 77–98). The median primary patency was 87 days (95% CI, 73–293). Stent grafts of ≥6-mm diameter retained patency for a longer duration than that with stent grafts of smaller diameters (6 mm vs 5 mm; hazard ratio, 0.35; 95% CI, 0.14–0.88; P = .026; and 7+ mm vs 5 mm; hazard ratio, 0.27; 95% CI, 0.09–0.83; P = .023). Anticoagulation/antiplatelet regimen was not associated with increased stent graft patency duration (P > .05). Only minor complications were reported in 2 (5.7%) patients.ConclusionsStent grafts can be used safely and effectively to treat injuries of the hepatic artery. Stent graft diameters of ≥6 mm seem to provide more durable patency.     

Evaluation of a Novel Spun Polytetrafluoroethylene Stent Graft in an Ovine External Iliac Artery Model

PurposeTo evaluate the patency, cellular response, and thrombogenicity of a novel vascular stent graft.Materials and MethodsTest stent grafts, incorporating luminal spun polytetrafluoroethylene and a nonpermeable fluoropolymer layer, and control stent grafts, constructed of permeable expanded polytetrafluoroethylene, were implanted in the external iliac arteries of 14 adult sheep with a median weight of 73.4 kg ranging from 60.6–86.8 kg for 30 (n = 4), 90 (n = 4), and 180 (n = 6) days. Angiographic patency and percent diameter stenosis (%DS) were assessed at termination. Excised stent grafts were fixed and stained for histopathologic analysis, including neointimal coverage (NC) assessment.ResultsTest and control device migration occurred in 1 animal, resulting in test device thrombosis. Both devices were excluded from analysis. Mean %DS in test and control implants was 4.6% and 8.2% (P = .563), 2.0% and 10.9% (P = .363), and 2.1% and 10.3% (P = .009) at 30, 90, and 180 days, respectively. Median NC scores at 30, 90, and 180 days were significantly lower in middle test device sections (P < .05). Proximal and distal test and control sections exhibited similar median NC scores at all time periods (P > .05). When present, test and control devices exhibited no neointimal detachment from the graft surface. Except for the migrated test device, no thrombus was observed. Transgraft cellular migration was absent in test devices but present in control devices with tissue accumulation around the stent struts.ConclusionsTest and control devices demonstrated excellent patency in an ovine model. Compared to the control, test devices exhibited significantly lower %DS values at 180 days and significantly lower mid-device NC scores at 30, 90, and 180 days.     

Factors Affecting Recurrent Deep Vein Thrombosis after Pharmacomechanical Thrombolysis and Left Iliac Vein Stent Placement in Patients with Iliac Vein Compression Syndrome

PurposeThis study evaluated the factors affecting contralateral and ipsilateral recurrent deep vein thrombosis (DVT) after iliac vein stent placement in patients with iliac vein compression syndrome (IVCS).Materials and MethodsData from 130 patients (95 female patients) who underwent catheter-directed thrombolysis and stent placement for IVCS with left lower leg thrombosis at a single institution were retrospectively analyzed. Mean patient age was 69.0 ± 14.0 years old. Median follow-up was 14 months (range, 3–164 months). Anticoagulation therapy was prescribed for 6 months, followed by lifelong antiplatelet therapy. Multivariate logistic regression analysis was performed to evaluate the factors affecting the development of contralateral and ipsilateral recurrent DVT.ResultsSeven patients (5.4%) developed contralateral DVT (median, 26 months; range, 2–61 months), and 11 patients (8.5%) developed ipsilateral DVT (median, 1 month; range, 0–53 months). Stent location (odds ratio [OR], 11.564; 95% confidence interval [CI], 1.159–115.417) and in-stent thrombosis during follow-up (OR, 15.142; 95% CI, 1.406–163.119) were predictors of recurrent contralateral DVT. Thrombophilia (OR, 47.560; 95% CI, 2.369–954.711), remaining inferior vena cava filter (OR, 30.552; 95% CI, 3.495–267.122), and in-stent thrombosis during follow-up (OR, 82.057; 95% CI, 2.915–2309.848) were predictors of ipsilateral DVT.ConclusionsContralateral DVT occurs late and is associated with extension of the iliac vein stent to the inferior vena cava and in-stent thrombosis. Ipsilateral DVT occurs relatively early and is associated with thrombophilia, remaining inferior vena cava filter, and in-stent thrombosis.     

Factors Influencing in-Stent Occlusion after Femoropopliteal Artery Stent Placement with Intravascular Ultrasound Evaluation

PurposeTo investigate the rate and predictors of in-stent occlusion by intravascular ultrasound (IVUS) following femoropopliteal artery stent placement.Materials and MethodsFrom July 2012 to June 2016, this study retrospectively investigated 191 cases of de novo femoropopliteal artery lesions (lesion length, 170 ± 97 mm; chronic total occlusion, 51%) evaluated by IVUS in 162 patients with peripheral artery disease (with critical limb ischemia of 27%) who underwent endovascular therapy using self-expanding nitinol stents. Examination by IVUS was performed to record data for vessel characteristics immediately after wire crossing and at the end of the procedure. The primary outcome measurement was the occurrence of in-stent occlusion, defined as the absence of blood flow at the treatment site by duplex ultrasonography. Predictors for in-stent occlusion were also evaluated by multivariate analysis.ResultsIn-stent occlusion was observed in 15% (n = 28) of lesions, and the mean follow-up time was 19 ± 13 months. After multivariate analysis, it was found that plaque burden ≥60% after stent placement (P < .001), female gender (P = .002), and Trans-Atlantic Inter-Society Consensus (TASC) II classification C and D lesions (P = .047) were significantly associated with the occurrence of in-stent occlusion.ConclusionsPlaque burden ≥60% after stent placement, female gender, and TASC II classification C/D lesions were significantly associated with the occurrence of in-stent occlusion after femoropopliteal artery stent placement as evaluated by IVUS.     

Evaluation of Technical Success,Efficacy, and Safety of Portomesenteric Venous Intervention following Nontransplant Hepatobiliary or Pancreatic Surgery

PurposeTo evaluate technical success, efficacy and safety of portomesenteric venous (PMV) intervention for PMV stenosis or occlusion following nontransplant hepatobiliary or pancreatic (HPB) surgery.Materials and MethodsA retrospective review identified 42 patients (mean age 60 y) with PMV stenosis (n = 33; 79%) or occlusion (n = 9; 21%) who underwent attempted PMV intervention following HPB surgery between June 1, 2011, and April 1, 2018. Main outcomes were technical success, primary patency rates, and complications. Technical success was compared by venous pathology and primary PMV patency based on anticoagulation status after the procedure using Fisher exact test. Rates of primary patency by stent group were estimated using Kaplan-Meier method.ResultsTechnical success was 91% (n = 38/42) and significantly higher in patients with stenosis (n = 33/33; 100%) vs occlusion (n = 5/9; 56%) (P = .001). Primary presenting symptom resolved in 28 (87%) patients, including 6 (100%) patients with gastrointestinal bleeding. At mean imaging follow-up of 8.6 months ± 8.8, primary stent patency was 76%. There was no significant difference in primary stent patency based on anticoagulation status after the procedure (P = .48). There were 2 (4.8%) periprocedural complications.ConclusionsPortomesenteric venoplasty and stent placement following nontransplant HPB surgery is safe with a high rate of technical success if performed before chronic occlusion.     

The Effects of Protrusion into the Outflow Vein on Outcomes of Stent Grafts Used to Treat Cephalic Arch Stenoses in Dysfunctional Brachiocephalic Fistulae

PurposeTo assess long-term patency rates of cephalic arch stent grafts in brachiocephalic fistulae and the importance of device position.Materials and MethodsThis retrospective study reviewed 152 patients with dysfunctional brachiocephalic fistulae and cephalic arch stenosis treated with stent grafts (Viabahn; W. L. Gore) at a single tertiary center between 2012 and 2021. The median age was 67.5 years (range, 25–91 years), and the median follow-up period was 637 days (range, 3–3,368 days). A grading system of protrusion was applied: (a) Grade 0, no protrusion; (b) Grade 1, perpendicular; and (c) Grade 2, in-line protrusion. Subsequent fistulograms were available in 133 (88%) of the 152 patients and were assessed for central vein stenosis within 10 mm of the stent graft. Clinical records were assessed for sequelae of stent graft protrusion. Stent graft primary and cumulative circuit patencies were calculated using the Kaplan-Meier method.ResultsProtrusion was documented in 106 (70%) stent grafts—56 Grade 1 and 50 Grade 2. Central vein stenosis was seen in 1 (2%) case of no protrusion (Grade 0) and 38 (40%) cases of protrusion (P < .0001). There was no significant difference in stenosis between Grade 1 and 2 protrusion (P = .15). No adverse clinical sequelae occurred in 147 (97%) patients. Eight patients had a new access subsequently formed in the same arm, and 3 of these 8 patients developed symptoms due to the previous stent graft protrusion (all Grade 2). The primary patency rates of the stent-grafts at 6 and 12 months were 73% and 50%, respectively. The cumulative access circuit patency rates at 1, 2, and 5 years were 84%, 72%, and 54%, respectively.ConclusionsThis study demonstrated that protrusion of a cephalic arch stent graft into the central vein is safe and only clinically relevant when a subsequent ipsilateral access is created.     

Stent Diameter,Not Cephalic Arch Anatomy,Predicts Stent Graft Patency in Cephalic Arch Stenosis

PurposeTo investigate the relationship between anatomic factors and primary patency of brachiocephalic arteriovenous fistulae (AVFs) after stent graft (SG) placement for cephalic arch stenosis (CAS).Materials and MethodsThis retrospective study reviewed all cephalic arch SGs placed in brachiocephalic AVFs in a tertiary academic medical center between 2014 and 2017. Sixty-three patients were included in the study. The mean patient age at the time of SG placement was 62.6 years ± 19, and the mean patient follow-up was 1,994 days ± 353. A cohort of patients (n = 31) who underwent brachiocephalic fistulograms for CAS but only received percutaneous transluminal angioplasty (PTA) was the control group. Patient demographic characteristics, AVF anatomy, SG type, and clinical outcomes were reviewed. The duration of primary cephalic arch patency after SG placement was compared with that after previous PTA.ResultsThe median AVF age at the time of data retrieval was 345 days. The primary patency of CAS after SG placement at 6 months, 12 months, and 3 years was 64%, 49.9%, and 23.5%, respectively. Primary cephalic arch patency was significantly associated with the SG diameter (P = .007) but not with cephalic vein–axillary vein junction anatomy, size of feeding artery, or SG length (P > .05). The primary patency of CAS in patients treated with PTA only (n = 31) at 6 months, 12 months, and 3 years was 61%, 35%, and 0%, respectively, which was significantly lower than that in patients treated with SG placement (P = .01).ConclusionsThis study showed that the primary patency of CAS after SG placement was significantly higher than that of PTA-only treatment. Moreover, primary cephalic arch patency after SG placement was significantly associated with the SG diameter.