Applying patient characteristics,stent-graft selection,and pre-operative computed tomographic angiography data to a machine learning algorithm: Is endoleak prediction possible?

IntroductionThis study aims to predict endoleak after endovascular aneurysm repair (EVAR) using machine learning (ML) integration of patient characteristics, stent-graft configuration, and a selection of vessel lengths, diameters and angles measured using pre-operative computed tomography angiography (CTA).MethodsWe evaluated 1-year follow-up CT scans (arterial and delayed phases) in patients who underwent EVAR for the presence or absence of an endoleak. We also obtained data on the patient characteristics, stent-graft selection, and preoperative CT vessel morphology (diameter, length, and angle). The extreme gradient boosting (XGBoost) for the ML system was trained on 30 patients with endoleaks and 81 patients without. We evaluated 5217 items in 111 patients with abdominal aortic aneurysms, including the patient characteristics, stent-graft configuration and vascular morphology acquired using pre-EVAR abdominal CTA. We calculated the area under the curve (AUC) of our receiver operating characteristic analysis using the ML method.ResultsThe AUC, accuracy, 95% confidence interval (CI), sensitivity, and specificity were 0.88, 0.88, 0.79–0.97, 0.85, and 0.91 for ML applying XGBoost, respectively.ConclusionsThe diagnostic performance of the ML method was useful when factors such as the patient characteristics, stent-graft configuration and vessel length, diameter and angle of the vessels were considered from pre-EVAR CTA.Implications for practiceBased on our findings, we suggest that this is a potential application of ML for the interpretation of abdominal CTA scans in patients with abdominal aortic aneurysms scheduled for EVAR.     

False Lumen Stent-Grafts for Repair of Postdissection Aortic Aneurysms

PurposeTo evaluate the safety and efficacy of false lumen (FL) stent-grafts in the treatment of postdissection aortic aneurysms.Materials and MethodsEleven patients who underwent endovascular repair using FL stent-grafts from January 2016 to June 2019 were included. Among them, 2 patients had a prior history of type A aortic dissection, whereas 9 had undergone a prior endovascular repair for type B aortic dissection. Computed tomography angiography was performed to evaluate the reintervention and technical success rate, aortic remodeling, and other related aortic complications.ResultsThe mean age of patients was 55.6 ± 10.4 years. Technical success was achieved in all patients, and neither early mortality nor paralysis occurred. In total, 8 visceral branch arteries originating from the FL were reconstructed. The true lumen areas at the celiac axis, superior mesenteric artery, renal artery, and abdominal aortic bifurcation were significantly increased from 230.1 mm² to 312.3 mm², 212.1 mm² to 277.5 mm², 209.1 mm² to 291.6 mm², and 214.4 mm² to 300.6 mm², respectively (P < .05). The total diameter of the aorta at the 4 designated levels was stable or had shrunk in all patients. At a mean follow-up of 18.9 ± 7.6 months, 1 patient received re-intervention owing to iliac stent-graft occlusion. No aortic-related mortality occurred.ConclusionsFL stent-grafts can safely and effectively treat patients with postdissection aortic aneurysms. This strategy can be used to promote thrombosis of the FL and aortic remodeling. A larger sample and an extended follow-up period are needed to produce more conclusive results.     

Percutaneous Arteriovenous Fistula Creation with the WavelinQ 4-French EndoAVF System: A Single-Center Retrospective Analysis of 30 Patients

PurposeTo retrospectively assess the safety and efficacy of percutaneous arteriovenous fistula (pAVF) creation with the WavelinQ 4-F EndoAVF System.Materials and MethodsFrom February 2018 to June 2020, 30 pAVFs were created in 30 consecutive patients (men; age, 55.3 years ± 13.6). Of the 30 patients, 21 (70%) were already on hemodialysis using a central venous catheter. The primary outcome measures were technical success, complications, and cannulation rate. The secondary outcome measures included the number of secondary procedures needed for cannulation, maintenance time to cannulation, and pAVF survival.ResultsTechnical success was 100%. The adverse event rate was 6.7% (2/30), including a pseudoaneurysm of the brachial artery that developed immediately after sheath removal and an aneurysm of the anastomosis 17 days after the procedure, which was treated with a covered stent placed in the arterial side. The mean follow-up was 547 days ± 315.7 (range, 14–1,071 days). The cannulation rate was 86.7% (26/30). The mean time to cannulation was 61.3 days ± 32.5 (range, 15–135 days). The mean follow-up after cannulation was 566.2 days ± 252.7 (range, 35–1,041 days). Four pAVFs were thrombosed after cannulation, with 2 of them successfully declotted. Sixteen interventions were needed to achieve cannulation after the index procedure in 15 patients (overall, 0.53 procedures/patient). Seven maintenance endovascular interventions (following cannulation) were performed during the follow-up period in 6 patients (overall, 0.27 procedures/patient, 0.17 procedures/patient-years). For the pAVFs that were cannulated, patency was 96% at 1 year, and 82% at 2 and 3 years, according to the Kaplan-Meier survival analysis.ConclusionsThis initial experience suggests that pAVF creation is safe and can be successfully performed with high maturation and long-term patency rates. Larger-scale prospective studies are needed to validate the results.     

The Effect of Smoking Cessation on the Technical Success of Endovascular Treatment for Thromboangiitis Obliterans

PurposeTo show that smoking cessation improves the technical success of lower extremity endovascular treatment in patients with thromboangiitis obliterans (TAO), or Buerger disease.Materials and MethodsOne hundred two patients with TAO who underwent endovascular treatment for chronic limb-threatening ischemia or severe claudication of lower extremities in a tertiary hospital between 2015 and 2022 were included in this retrospective study. Data on serum cotinine levels were available for the last 45 patients, and 38 patients constituted the study population. Per the institution’s protocol, patients were instructed to quit smoking 15 days before the intervention. However, cotinine levels showed that some of the patients continued smoking. Technical and recanalization successes were assessed as the primary end points. The secondary end point was the improvement in Rutherford scores at the 1-month follow-up. The McNemar test was used to compare the proportion of recanalized arteries after the intervention.ResultsThirty-seven men and 1 woman (mean age, 42.9 years ± 10.1) were evaluated. The overall technical success rate was 86.8% in the study group. The technical success rate was significantly higher in the nonsmoker group (n = 24 [96%]) than in the smoker group (n = 8 [61.5%]; P = .006). One-month clinical data were available for 100% of the patients. The Rutherford category of the nonsmoker group was significantly lower at the 1-month follow-up. In addition, the Wilcoxon signed-rank test revealed lower Rutherford scores after the intervention in the nonsmoker group. The adverse event rate was 8%. One (2.7%) patient in the smoker group underwent a minor amputation.ConclusionsCessation of smoking before endovascular therapy improved technical success and recanalization rates in patients with TAO.     

In Situ Laser Stent Graft Fenestration of the Left Subclavian Artery during Thoracic Endovascular Repair of Type B Aortic Dissection with Limited Proximal Landing Zones: 5-Year Outcomes

PurposeTo assess safety and feasibility of in situ laser stent graft fenestration to revascularize the left subclavian artery (LSA) during thoracic endovascular repair (TEVAR) of type B aortic dissection (TBAD) with limited proximal landing zones with 5 years of follow-up.Materials and MethodsIn a single-center retrospective study, 130 patients with TBAD with limited proximal landing zones (≤ 1.5 cm) underwent in situ laser stent graft fenestration revascularizing the LSA during TEVAR from April 2014 to April 2019. Outcomes were assessed by CT angiography and clinic visits, including technical success rate, operative time, LSA patency, ischemic events, and late aorta-related complications during follow-up.ResultsMean age of patients was 53 y (range, 33–73 y). Primary technical success rate was 96.9% (126/130). Three chimney stents were placed instead of fenestration, and 1 LSA fenestration was combined with a left common carotid artery (LCCA) chimney stent. Mean operative time was 53 min ± 28 with fluoroscopy time of 40 min ± 15. There were no neurologic complications and no deaths, with a mean duration of hospital stay of 9 d (range, 5–21 d). At a mean follow-up of 42 mo (range, 5–60 mo), there was a 97% primary LSA patency. Four patients had a type I endoleak, which disappeared during follow-up. One LCCA became occluded after 6 months. No type II or III endoleaks were found. Retrograde type A aortic dissection and stent graft–induced new distal entry were not found during follow-up.ConclusionsIn situ laser fenestration to revascularize the LSA during TEVAR of TBAD with limited proximal landing zones was efficient, safe, and feasible based on 5-year follow-up.     

Thoracic Endovascular Aortic Repair for Type B Aortic Dissection Associated with Retrograde Type A Intramural Hematoma

PurposeTo evaluate feasibility and efficacy of thoracic endovascular aortic repair (TEVAR) for type B aortic dissection (TBAD) associated with retrograde type A intramural hematoma (IMH).Materials and MethodsFrom April 2013 to January 2017, 15 consecutive patients with TBAD associated with retrograde type A IMH who underwent TEVAR were reviewed retrospectively. There was no cardiac tamponade, aortic regurgitation, involvement of coronary artery, or sign of cerebral ischemia in these patients. Enhanced CT was used in 4 patients to diagnose malperfusion of abdominal visceral arteries or lower extremity artery and underwent emergent TEVAR. For the remaining 11 patients, repeated enhanced CT after initial medical treatment within 24 hours from onset of pain showed expansion of IMH in 8 patients or presence of periaortic hematoma in 3 patients. Delayed TEVAR was scheduled for these cases.ResultsSuccessful deployment of the stent graft was achieved in all patients. There were no severe postoperative complications, such as retrograde type A aortic dissection or aortic rupture. Sudden death occurred in 1 patient 3 months after the procedure. Thrombosis of the false lumen, shrinkage of the diameter of the aorta, and complete absorption of the IMH were observed in the remaining patients at a mean follow-up of 19.8 months ± 6.57.ConclusionsTEVAR for treatment of TBAD with retrograde type A IMH is feasible and effective. It represents a treatment option for patients with TBAD associated with type A IMH with a proximal entry tear located in the descending aorta.     

Angiographic Findings during Repeat Prostatic Artery Embolization

PurposeTo describe mechanisms of prostate revascularization based on imaging findings during repeat prostatic artery embolization (PAE; rPAE).Materials and MethodsThis is a retrospective analysis of 10 rPAEs performed between October 2012 and September 2018 in patients with recurrent lower urinary tract symptoms (LUTS) after PAE (mean age, 68.2 y ± 4.5). Two interventional radiologists reviewed PAE and rPAE images and defined 6 patterns of revascularization. Correlation between embolization of the posterolateral (PL) prostatic branch during previous PAE and prostate revascularization on rPAE was assessed by Fisher exact test. One hemiprostate was excluded because no detectable revascularization was observed.ResultsAll patients showed LUTS improvement after previous PAEs (P < .01 for 5 outcome measures) and had recurrence during follow-up. rPAEs were performed a mean of 40.9 months after previous PAEs (18–96 mo). Of 19 hemiprostates analyzed, 11 presented revascularization by 2 or more branches (57.9%). The PL branch (29.0%) and the recanalized main prostatic artery (25.8%) were the most frequent revascularizing branches observed, followed by distal branches of obturator (12.9%), internal pudendal (12.9%), superior vesical (12.9%), and contralateral arteries (6.5%). Embolization of the PL branch during previous PAE significantly reduced the incidence of revascularization by this branch (P = .002).ConclusionsMechanisms of revascularization in rPAE are diverse and complex. Revascularization by the PL branch and recanalization of the previously embolized prostatic artery were the most frequent patterns observed. Embolization of the PL branch may reduce the incidence of prostate revascularization and LUTS recurrence after PAE.     

Radiation-Free Thoracic Endovascular Aneurysm Repair with Fiberoptic and Electromagnetic Guidance: A Phantom Study

PurposeTo evaluate the feasibility and accuracy of a radiation-free implantation of a thoracic aortic stent graft employing fiberoptic and electromagnetic tracking in an anthropomorphic phantom.Materials and MethodsAn anthropomorphic phantom was manufactured based on computed tomography (CT) angiography data from a patient. An aortic stent graft application system was equipped with a fiber Bragg gratings and 3 electromagnetic sensors. The stent graft was navigated in the phantom by 3 interventionalists using the tracking data generated by both technologies. One implantation procedure was performed. The technical success of the procedure was evaluated using digital subtraction angiography and CT angiography (before and after the intervention). Tracking accuracy was determined at various anatomical landmarks based on separately acquired fluoroscopic images. The mean/maximum errors were measured for the stent graft application system and the tip/end of the stent graft.ResultsThe procedure resulted in technical success with a mean error below 3 mm for the entire application system and <2 mm for the position of the tip of the stent graft. Navigation/implantation and handling of the device were rated sufficiently accurate and on par with comparable, routinely used stent graft application systems.ConclusionsThe study demonstrates successful stent graft implantation during a thoracic endovascular aortic repair procedure employing advanced guidance techniques and avoiding fluoroscopic imaging. This is an essential step in facilitating the implantation of stent grafts and reducing the health risks associated with ionizing radiation during endovascular procedures.     

Endovascular Outcomes in Aortic Arch Repair with Double and Triple Parallel Stent Grafts

PurposeTo report early and midterm outcomes of treating thoracic aortic aneurysm (TAA) and aortic dissection (AD) involving zone 1 and zone 0 with multiple parallel stent grafts (PSGs).Materials and MethodsFrom February 2011 to August 2018, 31 of 1,806 patients (1.7%) who underwent thoracic endovascular aortic repair (TEVAR) with double PSGs (DPSGs) (n = 20) or triple PSGs (TPSGs) (n = 11) were retrospectively reviewed. Procedures were performed in high-risk patients who had TAA or AD involving zone 1 or zone 0.ResultsFifteen patients (48.4%) who presented with symptomatic or impending rupture underwent urgent or emergent TEVAR with DPSGs or TPSGs. Nineteen patients (61.3%) were treated for zone 0 disease. Technical and clinical success rates were 70.0% for DPSG cohort and 45.5% for TPSG cohort. Intraoperative type Ia endoleak was observed in 30% of DPSG cohort and 45.5% of TPSG cohort. One patient in the DPSG cohort died of aortic sinus rupture intraoperatively. Minor stroke during the 30-day postoperative period was more frequent in the TPSG cohort (P = .042). Mean duration of follow-up was 28.9 months ± 17.7. The TPSG cohort had a higher incidence of major adverse events (72.7% vs 25.0%, P = .021). The most common adverse events were endoleaks (12.9%), endograft migration (9.7%), PSG stenosis or occlusion (6.5%), retrograde dissection (6.5%), and stroke (3.2%). Endograft migrations were more common in TPSG cohort (27.3%, P = .037). Overall mortality rate was 16.1% (5/31) perioperatively and during follow-up. There were no statistical differences in overall survival and reintervention-free survival.ConclusionsIn the context of TEVAR with multiple PSGs for aortic arch repair, TPSGs may have a high risk of major complications.     

Endovascular Lymphatic Decompression via Thoracic Duct Stent Placement for Refractory Ascites in Patients with Cirrhosis: A Pilot Study

PurposeTo evaluate the technical and clinical success of endovascular lymphatic decompression via thoracic duct (TD) stent placement in patients with cirrhosis with refractory ascites.Materials and MethodsNine patients (6 men and 3 women; median age, 66 [interquartile range {IQR}, 65–68] years; range, 62–78 years) who underwent TD stent placement for refractory ascites with contraindications for liver transplantation and transjugular intrahepatic portosystemic shunt creation were included in this retrospective study. TD stent placement was performed under local anesthesia using retrograde access from the venous system. Self-expanding stents from 5 to 8 mm in diameter were used and extended into the subclavian vein by approximately 1 cm. Technical (correct positioning of the stent) and clinical success (no more requirement of paracentesis) were evaluated. In addition, the safety of the procedure and TD pressure evolution were evaluated.ResultsThe technical success rate was 100%, and 3 (33%) patients reported clinical success. Five (56%) patients reported 7 minor adverse events (Grade I), among which 2 TD perforations were induced by stent angioplasty, with no clinical manifestation or treatment required. The median TD pressure decreased from 19 mm Hg (IQR, 11–24 mm Hg) at the beginning of the procedure to 6 mm Hg (IQR, 5–11 mm Hg) after TD stent placement. The median survival time after the procedure was 7.1 months.ConclusionsEndovascular lymphatic decompression via TD stent placement is feasible and safe and was effective on ascites in some patients with cirrhosis with refractory ascites.     

Long-Term Outcomes of Endovascular Interventions in More than 500 patients with Budd–Chiari Syndrome

PurposeTo assess and compare the long-term outcomes of various endovascular interventions in patients with Budd-Chiari syndrome (BCS).Materials and MethodsIn this single-center retrospective study, 510 consecutive patients with BCS who had undergone a total of 618 endovascular procedures from January 2001 to December 2019 were included. Details of the type of endovascular intervention, technical success, clinical success, patency rate, complications, and survival outcomes were analyzed.ResultsThe overall technical success rate was 96% (593 of 618 procedures; 500 in treatment-naïve patients and 93 repeat interventions for recurrent disease). Endovascular procedures included recanalization procedures (angioplasty and stent placement) in 355 patients (71%) and transjugular intrahepatic portosystemic shunt (TIPS) creation in 145 (29%). Major postprocedure complications occurred in 14 patients (2.8%). Vascular/stent restenosis occurred in 95 patients (19%), and successful repeat intervention was performed in 82 of those 95 (86.3%). An additional 11 of these 82 (13.4%) underwent a third intervention for restenosis. In the recanalization and TIPS groups, the 1- and 5-y cumulative patency rates were 87% and 74% and 95% and 68%, respectively. The 1- and 5-y survival rates were 96% and 89% and 90% and 76%, respectively.ConclusionsEndovascular interventions for BCS are feasible and safe in the majority of patients, with excellent short- and long-term patency and survival rates.     

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.     

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.     

Response Findings after Treatment and Outcomes on CT after Endovascular Repair of Mycotic Aortic Aneurysm

PurposeTo demonstrate post-treatment computed tomography (CT) findings and outcomes of endovascular aortic repair (EVAR) for mycotic aortic aneurysm (MAA).Materials and MethodsClinical data of patients with MAA who underwent EVAR from June 2010 to December 2017 were retrospectively reviewed. A total of 22 patients were included (19 men and 3 women). The periaortic features of the MAA regression after EVAR were graded and evaluated by follow-up CT.ResultsThe median follow-up was 36.5 months (range, 0.5–97 months.). The cumulative survival rate at 1 month, 6 months, 1 year, and 5 years was 95.5%, 86.4%, 81.6%, and 73.4%, respectively. The early and late infection-related complication (IRC) rate was 18.2% and 13.6%, respectively. One patient died within 1 month from severe acidosis and shock. Of the other patients, the median time to stable response of the MAA was 6 months (range, 3–36 months). Fourteen patients (66.7%) showed early response of the MAA, while 7 patients (33.3%) showed delayed response. A significant association was observed between delayed response and late IRCs (P = .026).ConclusionsThe post-EVAR periaortic features on follow-up CT aid in monitoring the treatment response of the MAA. Early response of the MAA was associated with a low rate of late IRCs and might aid in adjusting the antibiotic duration after the patient has achieved complete or nearly complete regression of the MAA.     

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.     

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.     

Predictors of Disease Recurrence after Venoplasty and Stent Placement for May–Thurner Syndrome

PurposeTo identify factors independently associated with disease recurrence after venoplasty and stent placement for May–Thurner syndrome (MTS).Materials and MethodsFifty-nine consecutive patients (age, 47 y ± 15; 93% female) were identified who had undergone endovascular stent placement for MTS. Patient charts were reviewed for demographic data, risk factors for venous thrombosis, comorbidities, and venous inflow or outflow at first follow-up (3 wk to 6 mo after treatment). Logistic regression was used to identify independent predictors of symptom recurrence or repeat intervention, and multivariate analysis of variance and receiver operator characteristic curve analysis were used to assess relationships between degrees of in-stent stenosis and other variables in the 73% of patients with available cross-sectional imaging. Median follow up was 20.7 months (interquartile range, 4.7–49.5 mo).ResultsAll procedures were technically successful. Disease recurrence, defined as symptom recurrence following initial postprocedural resolution, was observed in 38% of patients. No preprocedural variable was found to be independently predictive of disease recurrence; however, poor venous inflow or outflow were both strongly associated with recurrent disease, with adjusted odds ratios and 95% confidence intervals of 38.02 (3.76–384.20; P = .002) and 7.00 (1.15–42.71; P = .04), respectively. Higher degrees of in-stent stenosis were also associated with symptom recurrence, with an area under the curve of 0.93 (P = .000002) and 39%–41% stenosis being 78%–83% sensitive and 88%–92% specific for symptom recurrence.ConclusionsThese results suggest that cross-sectional imaging can help differentiate patients in whom closer follow-up may be warranted after venoplasty and stent placement for MTS and also guide counseling regarding prognosis.     

The Effect of Endovascular Treatment of Renal Artery Stenoses on Coexistent Aneurysms Associated with Fibromuscular Dysplasia

PurposeEndovascular data on patients with coexistent renal artery stenosis (RAS) and renal artery aneurysm (RAA) caused by fibromuscular dysplasia (FMD) are scarce, and the outcomes from RAS-specific treatment on RAA remain unclear. This study aimed to evaluate the safety and effectiveness of RAS-specific endovascular management in patients with coexisting RAA caused by FMD.Materials and MethodsClinical and endovascular data on 19 patients with coexistent RAS and RAA caused by FMD who underwent RAS-specific endovascular therapy were analyzed prospectively. An RAA located within 10 mm of the RAS was defined as a stenosis-related RAA (SRAA), and long-term outcomes were evaluated.ResultsNineteen patients (24 RASs and 30 RAAs) underwent endovascular therapy. Twenty-one RASs were treated with balloon angioplasty alone, whereas 3 RASs were treated with stent implantation. None of the RAAs were treated directly. During an average of 4.2 years ± 3.2 of follow-up, systolic and diastolic blood pressures decreased from 183.0 mm Hg ± 19.5 and 120.2 mm Hg ± 19.0 to 127.9 mm Hg ± 10.3 and 80.9 mm Hg ± 6.9, respectively; the number of antihypertensive medications reduced from 1.7 ± 1.0 to 0.8 ± 0.3 (for all, P < .001). The serum creatinine level remained stable. The maximum diameter of all RAAs decreased from 14.6 mm ± 9.7 to 11.3 mm ± 8.4 (P < .001). There was a significant difference in the improvement rate of the maximum diameter between SRAAs (65.0%, 13 of 20) and non-SRAAs (20.0%, 2 of 10) (P = .019).ConclusionsRAS-specific endovascular therapy is safe and effective and possibly aids in preventing RAA progression in patients with FMD with coexistent RAS and RAA.     

Predictive Value of Preprocedural Computed Tomography Angiography for the Technical Success of Transarterial Embolization of Type II Endoleaks Arising from the Lumbar Arteries

PurposeTo evaluate the ability of preprocedural computed tomography angiography (CTA) to predict the technical success of embolization of type II endoleak arising from a lumbar artery after endovascular aortic repair (EVAR).Materials and MethodsAll patients at a single academic institution who underwent angiography with possible embolization for a post-EVAR lumbar-supplied type II endoleak from 2009 to 2018 were retrospectively reviewed. Patients who did not undergo CTA before the procedure were excluded. CTAs were reviewed for the ability to trace the entire course of a feeding vessel from the internal iliac artery (IIA) to the lumbar artery at the site of the endoleak. Procedural imaging was reviewed for technical success, defined as the catheterization and embolization of the aneurysm sac through a lumbar artery.ResultsFifty-seven angiograms with a type II endoleak and suspected feeding lumbar artery were identified. On CTA acquired before the procedure, the arterial path supplying this lumbar artery could be traced from the IIA to the aneurysm sac in 18 (32%) patients. Embolization was technically successful in 16 of these 18 (89%) procedures compared with 10 of 39 (26%) procedures in which the supplying artery could not be traced using CTA (P < .001).ConclusionsA potential catheter path from the IIA through the iliolumbar and lumbar arteries to the aneurysm sac can be traced on preprocedural CTA in the minority of lumbar-supplied type II endoleaks. The ability to trace these inflow vessels may predict technical success during embolization. The low rate of technical success when the feeding vessel could not be traced using CTA suggests that these patients should be considered for percutaneous or transcaval sac puncture.