Pivotal Evaluation of Novel Dedicated Venous Stent for Iliofemoral Venous Obstruction: A Prospective Cohort Study.

PURPOSE: The purpose was to evaluate the clinical outcomes of a dedicated venous stent with the tripartite composite segments for the treatment of iliofemoral venous obstruction (IVO) in a mixed cohort of nonthrombotic iliac vein lesion (NIVL) and post-thrombotic syndrome (PTS) over a period of 12 months. METHODS: The Grency Trial is a prospective, multicenter, single-arm, open-label, pivotal study, which was conducted at 18 large tertiary hospitals in China from August 2019 to October 2020. A total of 133 hospitalized patients were screened and 110 patients with clinical, etiology, anatomical, and pathophysiology clinical class (CEAP) clinical grade C>3 and iliac vein stenosis >50% or occlusion, including 72 patients with NIVL and 38 patients with PTS, were implanted with Grency venous stents. Primary endpoint was stent patency at 12 months follow-up, and secondary outcomes were technical success; improvement in venous clinical severity score (VCSS) at 3, 6, and 12 month follow-up; and rates of clinical adverse events. RESULTS: Among 110 patients who were implanted with Grency venous stents, 107 patients completed the 12 month follow-up. All 129 stents were successfully implanted in 110 limbs. Twelve-month primary patency rate was 94.39% [95% confidence interval [CI]=88.19%-97.91%] overall, and 100% [94.94%-100%] and 83.33% [67.19%-93.63%] in the NIVL and PTS subgroups, respectively. Venous clinical severity score after iliac vein stenting improved significantly up to 12 months follow-up. There were 3 early major adverse events (1 intracerebral hemorrhage and 2 stent thrombosis events related to anticoagulation therapy), and 7 late major adverse events (1 cardiovascular death, 1 intracranial hemorrhage with uncontrolled hypertension, and 5 in-stent restenosis cases without stent fractures or migration). CONCLUSIONS: The Grency venous stent system appeared excellent preliminary safe and effective for IVO treatment. Further large-scale studies with longer-term follow-up are needed to evaluate long-term patency and durability of stent. CLINICAL IMPACT: The design of venous stents for iliofemoral venous obstruction (IVO) must address engineering challenges distinct from those encountered in arterial stenting. The Grency venous stent, a nitinol self-expanding stent specifically tailored for IVO, features a composite structure designed to meet the stent requirements of various iliac vein segments. The Grency Trial is a prospective, multicenter, single-arm, open-label pivotal study aimed at evaluating the efficacy and safety of the Grency stent system. Following a 12-month follow-up period, the Grency venous stent system has demonstrated both safety and efficacy in treating iliofemoral venous outflow obstruction.

Is Stent Retraction to ReLieve Arterial Cerebral VaSospasm Caused by SAH (Stent-ReLACSS) Using PRELAX the Long-awaited Solution for Treatment of Posthemorrhagic Cerebral Vasospasm? : Treatment of Posthemorrhagic Cerebral Vasospasm with PRESET and PRELAX: Technical Aspects, Efficacy, and Safety Margins in a Case Series.

PURPOSE: Recent observational studies have indicated the efficacy of stent retriever devices for the treatment of posthemorrhagic cerebral vasospasm (CVS), both by deployment and on-site withdrawal into the microcatheter (stent angioplasty, SA) and deployment followed by retraction through the target vessel similar to thrombectomy (Stent Retraction to reLieve Arterial Cerebral vaSospasm caused by SAH, Stent-ReLACSS). This article reports the findings with each application of pRESET and pRELAX in the treatment of CVS. METHODS: We retrospectively enrolled 25 patients with severe CVS following aneurysmal subarachnoid hemorrhage. For the SA group, a stent retriever or a pRELAX was temporarily deployed into a narrow vessel segment and retrieved into the microcatheter after 3 min. For the Stent-ReLACSS group, a pRELAX was temporarily deployed into a narrow vessel and pulled back unfolded into the internal carotid artery. If intra-arterial vasodilators were administered, they were given exclusively after mechanical vasospasmolysis to maximize the effectiveness of the stent treatment. RESULTS: In this study fifteen patients and 49 vessels were treated with SA. All were technically successful without periprocedural complications; however, 8/15 patients (53.3%) required additional treatment of the CVS. A total of 10 patients and 23 vessel segments were treated with Stent-ReLACSS. All maneuvers were technically successful without periprocedural complications and all vessels showed significant angiographic improvement. No recurrent CVS requiring further endovascular treatment occurred in-hospital, and neither territorial ischemia in the treated vessels nor vascular injury were observed in follow-up angiography. CONCLUSION: Based on the presented data it appears that Stent-ReLACSS with pRELAX does not pose any additional risks when used to treat CVS and might be superior to SA, especially concerning mid-term and long-term efficacy. The mechanism of action may be an effect on the endothelium rather than mechanical vasodilation. As many patients with CVS are diagnosed too late, prophylactic treatment of high-risk patients (e.g., poor grade, young, female) is potentially viable.

The Vascular Quality Initiative assessment of the Bard Lifestent for the treatment of popliteal artery occlusive disease.

OBJECTIVE: The Bard LifeStent self-expanding stent is approved for the treatment of occlusive disease involving the superficial femoral artery and proximal popliteal artery. We conducted a post-market trial of treatment of the popliteal artery above and below the knee (P1, P2, and P3 segments) within the Society for Vascular Surgery Vascular Quality Initiative (VQI) Peripheral Vascular Intervention registry. METHODS: A single-arm, prospective trial was conducted at 29 VQI sites in the United States, enrolling 74 patients from November 2016 to May 2019. The primary safety outcome was freedom from major adverse events including device-/procedure-related mortality and major amputation at 1 year. The primary efficacy outcomes were freedom from target vessel revascularization and freedom from target lesion revascularization at 1 year. Secondary outcomes included lesion success; procedural success; primary, primary-assisted, and secondary patency; and sustained clinical (improvement in Rutherford class) and hemodynamic success (increase in ankle brachial index >0.10). Outcomes were assessed by Kaplan-Meier analysis. Arteriogram of patients undergoing target lesion revascularization were assessed for stent fracture by a core laboratory. RESULTS: The mean age was 71 years, with 63.5% male and 55% with diabetes. The indication was claudication 28% and chronic limb-threatening ischemia in 72%. The superficial femoral artery-popliteal artery was stented in 38% and the popliteal artery alone in 62%. The majority of stents were placed in the P1 + P2 (39%) or P1 + P2 + P3 (37%) segments of the popliteal artery. The composite primary endpoint of freedom from major adverse events was 82% and 74% at 1 and 2 years, respectively. Freedom from mortality was 100% and 97%, and freedom from major amputation was 100% and 90% at 1 and 12 months, with all deaths and major amputations occurring in patients with chronic limb-threatening ischemia. freedom from target lesion revascularization was 86%, and freedom from target vessel revascularization was 84% at 12 months. At discharge, lesion treatment success was 99%, and procedural success was 82%. Primary patency was 80% and 72%, primary-assisted patency was 80% and 72%, and secondary patency was 89% and 82% at 12 and 24 months. Sustained clinical success was 98% and 95%, and sustained hemodynamic success was 100% and 79% at 12 and 24 months. CONCLUSIONS: In this multi-center, registry-based, single-arm prospective study the Bard LifeStent self-expanding stent demonstrated favorable performance in the challenging anatomy of the P2 and P3 popliteal segment. Post-market studies for label expansion of peripheral vascular intervention devices can be successfully conducted within the Society for Vascular Surgery VQI registry.

Torcular dural AVF: Transvenous onyx embolisation with sinus reconstruction.

Transvenous onyx (Microtherapeutics, Irvine, CA, USA) embolization with sinus reconstruction using a venous balloon is a novel technique to embolise dural arterial venous fistula while preserving the sinus. We elucidate the technical tips and tricks that were employed to treat this torcular dural AVF in an elderly male with visual disturbances secondary to papilledema. Right external carotid artery injection revealed a type 2c fistula along the torcula with feeders from the right parietal & petrosal branches of the middle meningeal artery and dural branches of the posterior auricular and the occipital artery. The right distal transverse and the sigmoid were occluded with retrograde flow into the superior sagittal sinus and the cortical veins. XPER CTA analysis revealed the fistula point to be along the wall of the torcula. Through right femoral artery access, a neuron max (Penumbra inc.USA) was placed in the right common carotid artery. An eclipse (Balt Extrusion, France) 6 × 12 mm single lumen balloon was placed in the proximal ECA to achieve flow reduction. Thereafter, through bilateral femoral venous approach, two neuron max 8 F (Penumbra inc.USA) were placed into the left jugular vein. A Copernic RC balloon 10×80 mm (Balt Extrusion, France) was placed from the left to the right transverse sinus. Further, two microcatheters, 1.5 F Marathon (Medtronic, Minneapolis, MI, USA) were navigated into the feeding arteries from the venous end. Microcatheter injections were taken with inflation of the venous balloon to determine the point at which sinus and cortical vein reflux is absent. Following that onyx 18 was injected under biplane fluoroscopy with an adequately inflated arterial and venous balloon. We could achieve retrograde permeation of the onyx into the fistula and the arterial feeders resulting in complete occlusion while preserving the sinus. Careful analysis of the angioarchitecture of the fistula and evaluating for delayed cerebral venous drainage is the key to determining the right strategy to achieve complete occlusion of the fistula.

A Case of Complete Resolution of Cauda Equina Syndrome Caused by Extensive Iliocaval Thrombosis: The Role of Thrombolysis and Venous Stents.

PURPOSE: The cauda equina syndrome (CES) is a rare condition affecting less than 1 in 100,000 patients annually. Diagnosing CES is challenging because of its rare incidence, potentially subtle presentation, and various underlying etiologies. Vascular causes, such as inferior vena cava (IVC) thrombosis, are uncommon but should be considered, since timely recognition and treatment of deep vein thrombosis (DVT) as a cause of CES can avoid irreversible neurological damage. CASE REPORT: A 30-year-old male presented with partial CES caused by nerve root compression due to venous congestion from an extensive iliocaval DVT. He completely recovered after thrombolysis and stenting of the IVC. His iliocaval tract remained patent until the last date of follow-up at 1 year without signs of post-thrombotic syndrome. Broad molecular, infectious, and hematological laboratory tests did not reveal any underlying disease for the thrombotic event, particularly no hereditary or acquired thrombophilia. CONCLUSION: Timely recognition of venous thrombosis as a cause of CES is essential. This is the first case report of CES caused by an extensive iliocaval DVT successfully treated with thrombolysis and venous stenting with good resolution of DVT and CES. CLINICAL IMPACT: This case-report describes a patient with cauda equina syndrome resulting from an extensive iliocaval deep vein thrombosis due to an underlying stenosis of the inferior vena cava. Thrombolysis and venous stenting succesfully restored venous patency and thereby relieved symptoms and signs of cauda equina syndrome, in addition to (long-term) therapeutic dose anticoagulation. It is important to timely recognize deep vein thrombosis as a cause of cauda equina syndrome and to consider endovenous treatment in a specialized center.

Basilar artery stenosis: Technical tips for endovascular revascularization.

The SAMMPRIS Trial concluded that medical treatment of intracranial stenosis was safer than intracranial stenting. The key reasons for a poor outcome with stenting were significantly more perioperative ischemic strokes and higher rates of intracerebral hemorrhages. To the contrary, WEAVE trial showed significantly lower morbidity and mortality when stenting was performed one week following the ictus. We describe the technical approach for safe basilar artery stenting through radial approach. A middle aged male presented with recurrent posterior circulation symptoms despite being on dual antiplatelet therapy. A right radial approach was undertaken. A 5f radial sheath was exchanged for an AXS infinity LS (Stryker Neurovascular, Ireland) 6 f sheath after priming the radial artery. Using a quadri-axial approach, 0.014' Traxcess microwire (Microvention Inc, Tustin, USA), 0.017' Echelon microcatheter (Microtherapeutics.inc. Ev3 Neurovascular, USA), 0.038 DAC (Stryker Neurovascular USA) & 5F Navien (Microtherapeutics.inc. Ev3 USA), the Infinity sheath was taken into the V2 segment of the right vertebral artery. The 5F Navien (tri-axial approach) was taken upto the distal V4 segment of the vertebral artery. The 3d rotational angiography directed runs revealed > 95 % stenosis of mid basilar segment. No significant ostial stenosis of side branch was noted and in view of long segment plaque angioplasty followed by deployment of self-expanding stent was planned. The microcatheter (0.017') and microwire (Traxcess 0.014') was navigated across the stenosis. Thereafter, an exchange maneuver was performed to allow for sequential slow balloon angioplasty with 1.5 mm × 15 (Maverick, Boston Scientific) and 2.5 mm× 15 (Trek, Abbott costa rica) coronary balloon. Following that a CREDO 4 × 20 mm stent (Acandis GmbH., Pforzheim Germany) was deployed across the stenosis. All exchange maneuvers were performed under biplane fluoroscopy and microwire was kept under watch. The patient was on aspirin and clopidogrel and activated clotting time was maintained around 250 s throughout the procedure. A closure device was applied post procedure. Blood pressure was monitored in neurointensive care unit and patient was discharged on the third day following procedure. Right radial approach, distal position of the sheath, distal position of the guiding catheter, careful analysis of the 3d rotational angiography for risk of side branch occlusion, biplane fluoroscopy during exchanges and slow angioplasty were the key safety checks during procedure.

Outcomes of the Gore® Excluder® Iliac Branch Endoprosthesis Using Self Expanding or Balloon-Expandable Stent Grafts for the Internal Iliac Artery Component.

OBJECTIVE: The GORE® EXCLUDER® Iliac Branch Endoprosthesis (IBE; W.L. Gore & Associates, Flagstaff, Arizona) was developed to be used in combination with a self-expanding stent graft (SESG) for the internal iliac artery (IIA) bridging stent. Balloon-expandable stent grafts (BESGs) are an alternative for the IIA, offering advantages in sizing, device tracking, precision, and lower profile delivery. We compared the performance of SESG and BESG when used as the IIA bridging stent in patients undergoing EVAR with IBE. METHODS: This is a retrospective review of consecutive patients who underwent EVAR with IBE implantation at a single center from October 2016 to May 2021. Anatomic and procedural characteristics were recorded via chart review and computed tomography (CT) postprocessing software (Vitrea® v7.14). Devices were assigned to SESG vs. BESG groups based on the type of device landing into the most distal IIA segment. Analysis was performed per device to account for patients undergoing bilateral IBE. The primary endpoint was IIA patency, and secondary endpoint was IBE-related endoleak. RESULTS: During the study period, 48 IBE devices were implanted in 41 patients (mean age 71.1 years). All IBE devices were implanted in conjunction with an infrarenal endograft. There were 24 devices in each of the self-expanding internal iliac component (SE-IIC) and balloon-expandable internal iliac component (BE-IIC) groups. The BE-IIC group had smaller diameter IIA target vessels (11.6±2.0 mm vs. 8.4±1.7 mm, p<0.001). Mean follow-up was 525 days. Loss of IIA patency occurred in 2 SESG devices (8.33%) at 73 and 180 days postprocedure, and in zero BESG devices, however, this difference was not statistically significant (p=0.16). There was 1 IBE-related endoleak requiring reintervention during the study period. A BESG device required reintervention due to Type 3 endoleak at 284 days. CONCLUSIONS: There were no significant differences in outcomes between SESG and BESG when used for the IIA bridging stent in EVAR with IBE. The BESGs were associated with using 2 IIA bridging stents and were more often deployed in smaller IIA target arteries. Retrospective study design and small sample size may limit the generalizability of our findings. CLINICAL IMPACT: This series compares postoperative and midterm outcomes of self expanding stent grafts and balloon expandable stent grafts (BESG) when used as the internal iliac stent graft as part of a Gore® Excluder® Iliac Branch Endoprosthesis (IBE). With similar outcomes between the two stent-grafts, our series suggests that some of the advantages of BESG, device sizing, tracking, deployment, and profile, may be able to be leveraged without impacting the mid-term performance of the IBE.

Computational modeling of braided venous stents - Effect of design features and device-tissue interaction on stent performance.

Designing venous stents with desired properties is challenging due to the partly conflicting performance criteria, e.g., enhancing flexibility may be at odds with increasing patency. To evaluate the effect of design parameters on the mechanical performance of braided stents, computational simulations are performed using finite element analysis. Model validation is performed through comparison with measurements. Considered design features are stent length, wire diameter, pick rate, number of wires, and stent end-type, being either open-ended or closed looped. Based on the requirements of venous stents, tests are defined to study the effect of design variations with respect to the following key performance criteria: chronic outward force, crush resistance, conformability, and foreshortening. Computational modeling is demonstrated to be a valuable tool in the design process through its ability of assessing sensitivities of various performance metrics to the design parameters. Additionally, it is shown, using computational modeling, that the interaction between a braided stent and its surrounding anatomy has a significant impact on its performance. Therefore, taking into account device-tissue interaction is crucial for the proper assessment of stent performance.

Novel Self-expanding Shape-Memory Bioresorbable Peripheral Stent Displays Efficient Delivery, Accelerated Resorption, and Low Luminal Loss in a Porcine Model.

OBJECTIVE AND DESIGN: The search for improved stenting technologies to treat peripheral artery disease is trending toward biodegradable self-expanding shape-memory stents that, as of now, still suffer from the acute trade-off between deliverability and luminal stability: Higher deliverability leads to lower lumen stability, vessel recoil, and stent breakage. This study was aimed at the development and testing of a self-expanding bioresorbable poly(l,l-lactide-co-ε-caprolactone) stent that was designed to produce confident self-expansion after efficient crimping, as well as quick bioresorption, and sufficient radial force. MATERIALS AND METHODS: Bench tests were employed to measure shape-memory properties, radial force, and hydrolytic degradation of the stent. The porcine model was employed to study deliverability, lumen stability, biocompatibility, and stent integrity. A total of 32 stents were implanted in the iliac arteries of 16 pigs with 15 to 180 day follow-up periods. The stented vessels were studied by angiography and histological evaluation. RESULTS: Recovery of the diameter of the stent due to shape-memory effect was equal to 90.6% after 6Fr crimping and storage in refrigeration for 1 week. Radial force measured after storage was equal to 0.7 N/mm. Technical success of implantation in pigs (after the delivery implemented by pusher) was 94%. At 180 days, no implanted stents were found to be fragmented: All of the devices remained at the site of implantation with no stent migration and all stents retained their luminal support. Only moderate inflammation and neoepithelialization were detected by histological assessment at 60, 90, 120, and 180 days. Lumen loss at 180 days was less than 25% of the vessel diameter. CONCLUSIONS: The stent with the mechanical and chemical properties described in this study may present the optimal solution of the trade-off between deliverability and luminal stability that is necessary for designing the next generation stent for endovascular therapy of peripheral arterial disease.

[Comparison of outcome of rigid and self-expanding stents for palliation of malignant dysphagia]. / A malignus eredetu dysphagia palliatív kezelésére használt merev és öntáguló sztentek eredményeinek összehasonlító vizsgálata.

INTRODUCTION: Between 1984 and 2019, 1005 rigid prostheses and 423 self-expanding stents were inserted for palliation of malignant esophageal stenosis. OBJECTIVE: The aim of this study was the comparison of the treatment results using the two types of prosthesis. METHOD: Retrospective analysis has been performed comparing the characteristics and treatment results of the two patients groups referring to the technical success of the procedures, procedure-related complications, change in the quality of life, and survival time. RESULTS: A comparison of average ages, duration time of dysphagia, quantity of weight loss, and the progress of the malignancy proves that palliation with self-expanding stents made it possible to treat more patients in worse condition. The number of complications in the patient group treated with stents was significantly higher at 29.3%/20.9%. Endoscopic intervention was performed to treat complications in 68.6% of cases with rigid prostheses and in 53.2% of patients treated with stents. Relevant improvement of dysphagia and the patients' quality of life was observed in 97% of those who were treated with a rigid prosthesis and in 91.3% of those who were treated with self-expanding stents. The survival time in the group of patients treated with stents was significantly shorter by 4.3/5.4 months than in the other group. CONCLUSION: The use of self-expanding stents in palliative treatment of malignant strictures have brought significant changes in everyday practice with increasing the possibilities. The treatment results were not improved by their application as much as the worse condition of the patient group worsened them. Orv Hetil. 2022; 163(49): 1952-1961.

Intracranial stenting as a bail-out option for posthemorrhagic cerebral vasospasm: a single-center experience with long-term follow-up.

BACKGROUND: Cerebral vasospasm (CVS) is a leading cause of morbidity and mortality in patients after aneurysmal subarachnoid hemorrhage (aSAH). Endovascular treatment, including intraarterial infusion of drugs with vasodilation effects, and balloon- and stentriever angioplasty, are helpful but may achieve only short-term effects. There is a clinical need for long-lasting treatment of refractory recurrent vasospasm. We report our experience in stent implantation as a treatment for recurrent severe post-SAH vasospasm. METHODS: A retrospective analysis of our institutional database of 883 patients with SAH, managed between January 2010 and December 2021, was performed. Six patients were identified as having received intracranial stenting in the context of post-SAH cerebral vasospasm. All patients were initially treated with intra-arterial infusion of nimodipine and/or milrinone. Self-expanding intracranial stents were implanted during endovascular aneurysm treatment to enable access despite impaired perfusion (Group 1) or as a bail-out strategy after failed intraarterial drug infusion or mechanical treatment (Group 2). All stented patients received dual antiplatelet therapy (DAPT) for 6 months. RESULTS: Nine vessels in six patients with severe post-SAH vasospasm were stented. The stents were deployed in 16 vessel segments. All attempted implantations were technically successful. All patients demonstrated radiographic and clinical improvement of the vessel narrowing. No recurrent vasospasm or permanent vessel occlusion of the stented vessels was encountered. A thrombus formation in a Group 1 patient resolved under 4 mg eptifibatide IA infusion. During long-term angiographic follow-up, neither in-stent stenosis nor stent occlusion was found. CONCLUSIONS: Endovascular implantation of self-expanding stents is a potential ultima ratio strategy for patients with severe refractory post-SAH cerebral vasospasm. Stents with reduced thrombogenicity (avoiding DAPT) and bioabsorbable self-expanding stents might further advance this concept.

Comparison of BARD®LIFESTREAM™ covered balloon-expandable stent versus GORE® VIABAHN™ covered self-expandable stent in treatment of aortoiliac obstructive disease: study protocol for a prospective randomized controlled trial (NEONATAL trial).

BACKGROUND: Covered stent has become one of the mainstream therapies for aortoiliac obstructive disease (AIOD), with a higher patency rate than bare metal stent. Covered balloon-expandable (CBE) stent can be placed more accurately with higher a radial support force, while covered self-expanding (CSE) stent has greater elasticity and higher trackability. However, there is no level I evidence regarding the comparison safety and efficacy between the CSE stent and CBE stent in AIOD to date. Therefore, this study aims to compare the efficacy and safety of CBE stent (BARD®LIFESTREAM™) and CSE stent (GORE® VIABAHN™) in AIOD. METHODS: This trial is a prospective, single-center, parallel, noninferiority, randomized controlled trial. A total of 106 patients will be enrolled and these patients will be randomized to either the CBE stent group or the CSE stent group. The primary end point of the study is the occurrence of target lesion revascularization (TLR) at 12 months after the intervention. DISCUSSION: To our knowledge, the ballooN sElf cOver steNt AorToiliAc occuLusive (NEONATAL) trial is the first RCT to compare CBE and CSE stent in AIOD patients. The main aim is to compare the TLR of the target lesion between CBE stent and CSE stent at 12 months post-procedure. The results of clinical trials may contribute to establishing a strategic guideline for choosing the optimal type of covered stent in the treatment of AIOD patients. TRIAL REGISTRATION: Chinese Clinical Trials Registry ChiCTR2100046734. Registered on 27 May 2021.

Oversizing of self-expanding Nitinol vascular stents - A biomechanical investigation in the superficial femoral artery.

Despite being commonly employed to treat peripheral artery disease, self-expanding Nitinol stents are still associated with relatively high incidence of failure in the mid- and long-term due to in-stent restenosis or fatigue fracture. The practice of stent oversizing is necessary to obtain suitable lumen gain and apposition to the vessel wall, though it is regarded as a potential cause of negative clinical outcomes when mis-sizing occurs. The objective of this study was to develop a computational model to provide a better understanding of the structural effects of stent sizing in a patient-specific scenario, considering oversizing ratio OS, defined as the stent nominal diameter to the average vessel diameter, between 1.0 and 1.8. It was found that OS < 1.2 resulted in problematic short-term outcomes, with poor lumen gain and significant strut malapposition. Oversizing ratios that were in the range 1.2 ≤ OS ≤ 1.4 provided the optimum biomechanical performance following implantation, with improved lumen gain, reduced incomplete stent apposition and favourable predicted long-term fatigue performance. Excessive oversizing, OS > 1.4, did not provide any further benefit in outcomes, showing limited increases in lumen gain and unfavourable long-term performance, with higher mean strain values predicted from the fatigue analysis. Therefore, our findings predict that the optimal oversizing ratio for self-expanding Nitinol stents is in the range of 1.2 ≤ OS ≤ 1.4, which is similar to clinical observations, with this study providing detailed insight into the biomechanical basis for this.

SUPERA Stenting in the Common Femoral Artery: Early Experience and Practical Considerations.

PURPOSE: Endovascular therapy in the management of de novo common femoral disease remains controversial. Considerable interest has been generated in recent years due to recent technological advancement in the design of vascular stents. In particular, SUPERA (Abbot Vascular Inc, Santa Clara USA) stents are designed to offer increased flexibility and less adverse interactions with the arterial wall, thus making it potentially better suited for common femoral lesions. However, despite such theoretical advantages, there is lack of data in its use in clinical practice. This study provides illustrative examples of SUPERA stents in different clinical settings and contributes to important clinical data for the overall efficacy and safety profile of endovascular interventions in common femoral artery (CFA) disease. MATERIALS AND METHODS: Retrospective analysis of all endovascular CFA procedures between January 1, 2011, and December 31, 2019, was conducted. Data collected included demographics, clinical symptoms, medical comorbidities, procedural characteristics, and immediate and short-term complications. Detailed analysis was performed on the stenting cohort. RESULTS: During our study period, a total of 69 patients underwent endovascular interventions involving the CFA at our institution, of which 16 patients had stenting procedures for a total of 18 stent deployments. Technical success was achieved in all stenting procedures. A total of 15 SUPERA stents were placed in 13 patients. No stent fractures were observed. Overall primary patency rate of SUPERA stents at the time of 12-month follow-up was 100% in patients who had a follow-up assessment (n = 12 stents). CONCLUSION: Endovascular intervention of the CFA is an evolving topic in the interventional radiology and vascular surgery community. Recent development of newer generation of devices such as SUPERA peripheral stents offers significant potential benefits given their inherent design. Despite the theoretically promising design of the SUPERA, there is a lack of data to support its use. This study contributes important patient-level data for SUPERA stent deployments.

Central airway obstruction treatment with self-expanding covered Y-carina nitinol stents: A single center retrospective analysis.

BACKGROUND: Central airway obstruction (CAO) is one of the most challenging, potentially lethal complications in malignant and benign respiratory diseases. Worsening dyspnea is also a relevant cause for reduced quality of life in such patients. Here, we present our data on the application of covered, self-expanding Y-carina nitinol stents due to benign and malignant diseases. METHODS: We retrospectively identified 27 patients who had undergone 31 rigid bronchoscopies with implantation of covered Y-carina nitinol stents over a period of 10 years in order to evaluate indication, clinical course, and outcome. RESULTS: Short-term survival of successfully stented patients with palliative and curative treatment goal did not differ, allowing for diagnosis independent indication. With respect to overall survival, patients with endoluminal obstruction benefited most compared to patients with fistula and/or external compression. Granulation tissue formation (61.3%) and mucus plugging (80.6%) were the most frequent complications. Material defect (6.5%) and migration (3.2%) were rare complications that could be handled by revisional rigid bronchoscopy and stent exchange in some cases. CONCLUSIONS: Implantation of self-expanding covered Y-carina nitinol stents via rigid bronchoscopy is a feasible and safe treatment option for benign and malignant central airway obstruction. Especially in palliative, malignant airway stenosis, stenting might facilitate additional treatment options and optimize dyspnea and eventually quality of life.

Exploiting the Transformation Temperature to Reform an Infolded Nitinol Self-Expanding Peripheral Stent.

PURPOSE: Nickel-titanium (nitinol) alloys possess a special set of properties that allow for a wide range of applications. Specifically, the transformation temperature for self-expanding nitinol peripheral stents allows for easy crimping at or below room temperature and reformation at body temperature becoming superelastic. CASE REPORT: We report the case of an elderly man with iliac stenting 1 month prior, who presented several weeks after recovering from coronavirus disease 2019 with recurrent anterior-wall ST-elevation myocardial infarction. This was complicated by deformation and infolding of the previously implanted nitinol self-expanding stent in his right common iliac artery (CIA). Understanding nitinol's specific properties, we proceeded with rapid injections of iced saline to cool the nitinol stent to its transformation temperature while nudging the distal end of the stent with a partially inflated balloon. This maneuver softened the nitinol stent, allowing us to "unfold" and reappose it against the wall of the right CIA, resulting in successful restoration of the original shape of the nitinol self-expanding stent. CONCLUSION: This represents the first reported case describing treatment of an infolded nitinol self-expanding peripheral stent by exploiting the transformation temperature of nitinol using iced cold saline to successfully restore the stent's original shape and structure.

BioMimics 3D vascular stent system for femoropopliteal interventions.

Background: The MIMICS-3D study aimed to assess the safety and effectiveness of the BioMimics 3D Vascular Stent System for the treatment of symptomatic femoropopliteal artery disease in a real-world patient population. Patients and methods: Consecutive participants who were scheduled for implantation of the BioMimics 3D stent were enrolled in the prospective, observational, multicenter study. The primary effectiveness outcome was freedom from clinically driven target lesion revascularization at 12 months and the primary safety outcome was a composite of major adverse events comprising death, major target limb amputation, or clinically driven target lesion revascularization at 30 days. Outcomes through 24 months are reported. Results: A total of 507 patients (70±10 years, 65.5% male sex) were enrolled and treated with the study stent. 24.0% had critical limb-threatening ischemia, lesion length was 127±92 mm, and 56.8% of lesions were totally occluded. The Kaplan-Meier (KM) estimate of freedom from clinically driven target lesion revascularization at twelve-months was 90.6% (95% CI: 87.9%-93.3%) and the 30-day primary safety outcome occurred in 1.2% (95% CI: 0.5%-2.7%) of participants. At 24 months, clinical improvement was achieved in 86.6% and the KM estimate of freedom from clinically driven target lesion revascularization was 82.8% (95% CI: 79.4%-86.4%). The KM estimate of freedom from loss of primary patency according to PSVR >2.4 was 78.6% (95% CI: 74.7%-82.4%). Survival distribution functions regarding primary patency were lower with long lesions (>150 mm; log-rank p<0.001) but did not differ significantly between participants with or without critical limb-threatening ischemia (log-rank p=0.07). Conclusions: Endovascular treatment of atherosclerotic femoropopliteal lesions with the BioMimics 3D Vascular Stent System is efficacious and safe in a real-world setting.

Experience in the management of neoplastic gastric outlet obstruction in patients at the Hospital Universitario San Ignacio in Bogotá, Colombia.

INTRODUCTION: Malignant gastric outlet obstruction is a condition that alters patient quality of life, conditioning progressive malnutrition. However, self-expanding metal stents (SEMSs) and surgical gastrojejunostomy (SGJ) are palliative options in patients with unresectable disease. AIM: To characterize patients diagnosed with malignant gastric outlet obstruction requiring SEMS placement or SGJ. MATERIALS AND METHODS: Sequential non-probability convenience sampling was conducted and included 68 patients, 40 of whom had SEMS placement and 28 of whom underwent SGJ. RESULTS: Patients sought medical consultations for the symptoms of vomiting, abdominal pain, weight loss, and upper gastrointestinal bleeding. Ninety-five percent of the patients in the SEMS group and 64.3% in the SGJ group presented with metastasis. Technical and clinical success, patency duration, and number of patients with no complications were greater in the SGJ group. Mean survival in days was 88 (SD ±â€¯21) in the SEMS group versus 501 (SD ±â€¯122) in the SGJ group. The log-rank test detected a statistically significant difference between subgroups (p = 0.00). CONCLUSION: SGJ has greater technical and clinical success rates but SEMS placement continues to be utilized in distal gastric cancer, especially in cases in which surgery is not an option.

Three-Year Clinical Outcomes of the Innova™ Self-Expanding Nitinol Stent for the Treatment of Femoropopliteal Lesions.

PURPOSE: To report the 3-year results of Innova™ stent implantation for the treatment of femoropopliteal (FP) lesions in a real-world setting. METHODS: This single-arm, retrospective, multicenter clinical study analyzed 481 lesions from 453 consecutive patients with symptomatic peripheral artery diseases (Rutherford category 1-6) who underwent endovascular therapy with implantation of Innova™ self-expanding nitinol stent for FP lesions. The primary outcome measure was the 3-year restenosis rate based on doppler-ultrasound or angiographic criteria. The secondary outcome measures included the rates of 3-year major amputation and major adverse limb events. RESULTS: Restenosis following Innova™ implantation was found in 61% of the cases at 3 years. At the end of 3 years, the rates of major amputations and major adverse limb events were 3 and 31%, respectively. In cases free from restenosis at 1 year, no predictive factors for restenosis at 3 years could be determined. CONCLUSION: The present study demonstrated mid-term clinical outcomes after Innova™ stent implantation for the treatment of FP lesions in a real-world population. The Innova™ stent demonstrated acceptable clinical outcomes in a real-world setting.

Comparative effectiveness of endovascular treatment modalities for de novo femoropopliteal lesions in intermittent claudication: A network meta-analysis of randomized controlled trials.

PURPOSE: To evaluate the most effective endovascular treatment modalities for de novo femoropopliteal lesions in intermittent claudication (IC) in terms of technical success, primary patency, target lesion revascularization (TLR) and all-cause mortality through network meta-analysis of randomized controlled trials. METHODS: Medical databases were searched on December 3, 2020. 16 studies (3265 patients) and 7 treatments were selected. Outcomes were technical success, primary patency, TLR and mortality at 6 and/or 12 months. RESULTS: Regarding 6-month primary patency, drug-eluting stents (DES) was better than balloon angioplasty (BA; odds ratio [OR], 23.27; 95% confidence interval [CI], 12.57-43.06), drug-coated balloons (DCB; OR, 5.63; 95% CI, 2.26-14.03) and directional atherectomy (DA; OR, 31.52; 95% CI, 7.81-127.28), and bare nitinol stents (BNS) was better than BA (OR, 17.91; 95% CI, 7.22-44.48), DCB (OR, 4.33; 95% CI, 1.40-13.45) and DA (OR, 24.27; 95% CI, 5.16-114.11). Regarding 12-month primary patency, DES was better than BA (OR, 10.05; 95% CI, 4.56-22.16), DCB (OR, 3.70; 95% CI, 1.54-8.89) and DA (OR, 29.54; 95% CI, 7.26-120.26). DCB and combination of balloon and atherectomy were the most effective treatment regarding 12-month TLR and technical success (residual stenosis <30%), respectively. DES, BNS and DA with DCB (DA-DCB) were included in the best cluster in the clustered ranking plot combining 12-month primary patency and TLR. CONCLUSIONS: Balloon and atherectomy may confer advantages over other treatments for technical success; DCB may for TLR. Stent technologies confer substantial advantages regarding primary patency. Stent technologies and DA-DCB should be given priority in treating femoropopliteal lesions in IC.