Stent Fracture Research Articles

Lethal Complication of Postairway Stenting to Trachea and Left Main Bronchus: A Case Series with Discussion of the Diagnosis and Management

Abstract The insertion of a metallic airway stent is a valuable method for the treatment of benign and malignant airway stenosis and tracheoesophageal fistula. Although stenting for airway stenosis has become widely popular with favorable outcomes, several complications can arise after stenting, such as migration, tendency for stent fracture, and ingrowth of tumor or granulation tissue into the stent. Very few of these reports have described the complications of poststenting pneumothorax. We report the cases of three patients diagnosed with squamous cell carcinoma of the esophagus, complicated by tracheoesophageal fistula, and treated with a tracheal stent or bronchial stent, who developed poststenting pneumothorax.

Safety and efficacy assessment of the Inno-Xmart venous stent system in managing symptomatic iliofemoral venous obstruction: a 12-month outcome analysis.

This study aims to evaluate the safety and efficacy of the dedicated Inno-Xmart braided venous stent system (Suzhou Innomed Medical Device Co., Ltd., Jiangsu, China) in treating symptomatic iliofemoral venous obstruction. This clinical study followed a prospective, multicentre, single-arm design with the application of an objective performance goal. Patients diagnosed with symptomatic iliofemoral venous obstruction who met the eligibility criteria of this study were enrolled and treated with the Inno-Xmart venous stent system. The safety endpoints included the assessment of stent fracture, satisfaction of delivery system and 12-month incidence rate of major adverse events (MAEs). The primary efficacy endpoint focused on evaluating the 12-month primary patency rate through venography as determined by core laboratory. Secondary efficacy endpoints included surgical success rate, 6-month primary patency rate and the changes in quality of life from baseline to 6- and 12-month follow-up intervals. Between September 18, 2019, and April 26, 2021, 193 patients were successfully enrolled across 18 research institutions. The surgical success rate was 95.3% (184/193), the 12-month MAE rate was 5.1% (9/178) with no stent fractures or migrations. The 12-month primary patency rate for the participants was 96.1%, significantly surpassing the literature-derived objective performance of 80% (95% confidence interval [CI], 92.1-98.4; P < 0.0001). In addition, the mean venous clinical severity score (VCSS) and Chronic Venous Disease Quality of Life Questionnaire (CIVIQ) scores at the 6- and 12-month follow-ups were significantly lower than the preoperative scores (P < 0.001). The innovative, dedicated braided venous stent designed to address symptomatic iliofemoral venous obstruction demonstrates a high technical success rate, low complication rates, and impressive mid-term (12-month) patency. It effectively enhanced the quality of life for patients and holds promising prospects for a wide range of applications. The clinical study was officially registered in the "Chinese Clinical Trial Registry" (Registration number: ChiCTR2000040216, date of registration: November 25th, 2020).

Insights into the biocompatibility of biodegradable metallic molybdenum for cardiovascular applications-a critical review.

Atherosclerotic cardiovascular disease (ACD) is the leading cause of death worldwide. The gold standard of treatment is the implantation of a permanent stent implant that is often associated with complications such as thrombus formation, vascular neointimal response, and stent fracture, which altogether decrease the long-term safety and efficacy of the stent. Biodegradable metallic materials have become an attractive alternative because of the ability to facilitate a more physiological healing response while the metal degrades. Recently, Molybdenum (Mo) has been considered as a potential candidate due to its excellent mechanical and medical imaging properties. Moreover, the biomedical research studies performed to date have shown minimal adverse effects in vitro and in vivo. However, there are still concerns of toxicity at high doses, and the impact of the biochemical mechanisms of Mo on material performance especially in pathophysiological environments are yet to be explored. Mo is an essential co factor for enzymes such as xanthine oxidoreductase (XOR) that plays a critical role in vascular homeostasis and ACD progression. Herein, this review will focus on the biochemistry of Mo, its physiological and pathological effects with an emphasis on cardiovascular disease as well as the recent studies on Mo for cardiovascular applications and its advantages over other biodegradable metals. The limitations of Mo research studies will also be discussed and concluded with an outlook to move this revolutionary metallic biomaterial from the bench to the bedside.

Is Delayed Stent Fracture Possible?: A Combined Enhanced Stent Visualization and IVUS Diagnosis

Is Delayed Stent Fracture Possible?: A Combined Enhanced Stent Visualization and IVUS Diagnosis

Major Complications of Deep Venous Stenting.

Deep venous stent placement has developed into a primary treatment modality for venous obstruction in recent decades. Reported rates of complications are low in the literature and are based mainly on case reports and single-centre cohorts. Interventionalists performing these procedures must be aware of the occurrence of complications associated with stent placement to counsel patients adequately and promote avoidance through optimal procedural approach. This study aims to determine the incidence of serious complications associated with iliocaval and iliofemoral stent placement in a cohort of patients from 3 major tertiary deep venous referral centres. Data were collated from January 2014 to September 2023. The following major complications were included in the analysis: death, major bleeding requiring transfusion, massive pulmonary embolism, any complication which required endovascular or open surgical intervention, vessel rupture, acute kidney injury requiring dialysis, stent crushing, fracture, migration, involution or erosion. One thousand eight hundred fourteen (1814) patients were treated for acute or chronic deep venous pathology during the 9-year study period. Sixty-one patients (3.3%) experienced a major stent-related complication. The most frequently reported complication was stent crushing (n = 18, 29.5%), followed by stent fracture (n = 10, 16.4%) and erosion of the stent through the vessel wall (n = 8, 13.1%). Death was a rare event (0.2%). Deep venous stent placement is a safe procedure with low rates of major complications. It is incumbent upon operators to be aware of the risks associated with these procedures, however, rare, so that they may obtain fully informed consent from patients.

Ascending Aorta Anastomotic Aneurysm Exclusion with Double-Fenestrated PMEG after Open Repair

The objective of this case series is to investigate the outcomes of double-fenestrated physician-modified endografts (PMEGs) in patients with distal anastomotic aneurysms after open repair of the ascending aorta or proximal arch replacement. All consecutive patients with a distal anastomotic aneurysm after open ascending aorta surgery who underwent aortic arch repair with a homemade double-fenestrated stent-graft from 2017 to 2023 were reviewed. Study endpoints included technical success, 30-day, and long-term follow up analysis of mortality, morbidity, and reinterventions. 10 patients were treated with double-fenestrated PMEGs for anastomotic aneurysms after open surgery of the ascending aorta. Of these, 9 were male with a mean age of 58years. Nine patients were initially treated for acute dissection, and 2 had mechanical aortic valves. The mean time between open surgery and the treatment of the pseudoaneurysm was 4.15years. Technical success was 100%. The proximal landing zone was consistently in zone 0, and all endografts were deployed via femoral access. Early outcomes revealed one endoleak (type 1a), which was successfully treated by prompt reintervention. No deaths or strokes occurred during the early postoperative period. During long-term follow up (mean time 35months), no endoleaks requiring intervention occurred, and there were no reports of stent fractures or migrations. No patient died from an aortic-related cause. Aortic arch repair with double-fenestrated PMEGs for distal anastomotic aneurysms after open surgery is feasible and represents a promising alternative in patients ineligible for redo surgery.

Safety and efficacy of covered stent grafts in the treatment of emergent access related complications

BackgroundLarge bore percutaneous access is becoming increasingly common. Parallel to this, we observe an increase in vascular access site complications such as bleeding, dissection, thrombosis or pseudo-aneurysms. This study was aimed to evaluate safety and efficacy of covered stent grafts for fixing large bore vascular access injuries. MethodsA total of 147 Viabahn or Viabahn VBX (WL Gore) stent grafts which were placed across the inguinal ligament in emergent settings in 136 patients, were retrospectively analyzed. The two endpoints were the technical success rate, defined by complete arterial repair, and long-term stent graft patency. We also looked at the need for open conversion, wound infections, and in hospital and 30-day mortality. We followed the patients using duplex ultrasound and computed tomography angiogram to assess for arterial patency, freedom from intervention, stent kinking and clinical symptoms. Results30 Viabahn and 117 Viabahn VBX (WL Gore) stent grafts were placed in the distal external iliac artery and into the proximal common femoral artery of 136 patients. Indications for intervention were bleeding in 92 patients (68 %), flow limiting dissection in 41 patients (30 %) and symptomatic AVF in 3 patients (2 %). Primary technical success rate was 100 %. Limited 3-year follow up (101/136 patients) showed 99 % patency with no evidence of stent fracture, stenosis or kinking except in one patient who needed target lesion revascularization due to neointimal hyperplasia. ConclusionsCovered stent grafts can be placed safely, efficiently, and effectively in the distal external iliac and common femoral arteries across the inguinal ligament. These stent grafts can be used as an alternative therapeutic option to open surgery in patients with large bore vascular access injuries.

Investigating the Frequency of Stent Fracture and its Impact on in-Stent Restenosis in Patients Undergoing Carotid Artery Stenting

Investigating the Frequency of Stent Fracture and its Impact on in-Stent Restenosis in Patients Undergoing Carotid Artery Stenting

Reintervention Rate after Treatment with the INCRAFT AAA Ultra–Low-Profile Stent Graft System

ObjectiveThe INCRAFT stent graft system is an ultra-low profile endograft for the exclusion of infrarenal aortic aneurysms. In the market approval studies, an increased rate of device-related complications was observed and the endograft was approved with mandated postmarketing investigations. Our aim was to analyze midterm outcomes of a real-world patient cohort treated with the INCRAFT endograft. MethodsConsecutive patients treated with the INCRAFT endograft between February 2015 and December 2022 at a single institution were included. In accordance with the Society for Vascular Surgery reporting standards, safety endpoints were reported and outcome endpoints included reinterventions, technical success, aortic-related and overall-mortality, endoleak, stent fracture, and endograft migration >5 mm. ResultsEighty patients (85% male) with a mean age of 76 ± 7 years were included. Fifty-two patients (65%) were treated within the endograft’s instruction for use (IFU). Mean aortic diameter was 59 ± 10 mm and 91% of the procedures were performed percutaneously. Mean follow-up was 37 ± 25 months and there was no aortic- or procedure-related mortality. Reinterventions occurred in 25 patients (31%) with a freedom from reintervention at 1, 3 and 5 years of 84%, 66% and 55%. The most frequent reinterventions were limb graft stenting (23%) and type II endoleak embolization (14%). Limb occlusion rate was 9% and in three patients (4%) distal endograft migrations >5 mm occurred. Persisting type II endoleaks were observed in 29% and aneurysm diameter was stable in 41% and had shrunk in 38%. Three type III endoleaks (4%) developed during follow-up and four open conversions (5%) were necessary. No known risk factors, including treatment outside IFU, were predictive for reinterventions. ConclusionTreatment of infrarenal aortic aneurysms with the INCRAFT stent graft system was safe and successful. Nevertheless, a substantial rate of reinterventions was necessary during follow-up to maintain endograft patency and prevent aneurysm growth.

BeGraft Aortic Stents: A European Multi-Centre Experience Reporting Acute Safety and Efficacy Outcomes for the Treatment of Vessel Stenosis in Congenital Heart Diseases.

Stent implantation has become the preferred method of treatment for treating vessel stenosis in congenital heart diseases. The availability of covered stents may decrease complications and have an important role in the management of patients with complex anatomy. This study aims to evaluate the feasibility and safety of the pre-mounted cobalt-chromium stent-graft-covered ePTFE Aortic BeGraft in a broad spectrum of vascular lesions. This is a multicenter retrospective results analysis of 107 implanted BeGraft stents between 2016 and 2022 in six different European centers. One hundred and four patients with a mean age of thirteen years (range 1-70 years) and with the body weight of 56.5 kg (range 11-115 kg) underwent the BeGraft stent implantation. Stents were implanted in the following conditions: aortic coarctation (74 patients), RVOT dysfunction (12 patients), Fontan circulation (7 patients), and miscellaneous (11 subjects with complex CHD). All the stents were implanted successfully. The median stent diameter was 16 mm (range 7-24 mm), and the median length was 39 mm (range 19-49 mm). Major complications occurred in five subjects (4.7%). During a median follow-up of fourteen (1-70) months, stents' re-dilatation was performed in five patients. The BeGraft stent can be used safely and effectively in a wide spectrum of congenital heart diseases. Whether these good results will be stable in the longer term still needs to be investigated in a follow-up given its recent introduction into clinical practice, in particular regarding stent fracture or neointimal proliferation.

Fatigue Test Method to Evaluate the 50 Year Durability of Venous Stents

Iliofemoral venous obstructive disease can result in significant, potentially debilitating symptoms that can negatively affect quality of life. Unlike arterial disease, patients with deep venous disease have a significantly lower median age, therefore the need for long term stent patency becomes a matter of decades rather than years. Furthermore, iliofemoral lesions frequently require stent placement across the inguinal ligament. Such stents are subject to dynamic stress from leg movement and associated concerns for device fatigue, resulting in stent fracture. The aim of this study was to describe an invitro 50 year stent fatigue test method designed to assess durability against dynamic stress induced device fracture. Through literature review, cadaver studies, and computer modelling, the most challenging loading was confirmed to be hip flexion across the inguinal ligament. This occurs when the patient adjusts between a seated and standing position. Sit to stand hip flexion at the inguinal ligament was effectively simulated on the bench in this invitro experimental study. When tested under challenge parameters, hip flexion was reliably found to cause fractures in non-venous nitinol stents. However, a dedicated self expanding nitinol venous stent, engineered for improved durability, underwent up to 50 years of simulated loading on the bench with 15% (3/20) of stents experiencing fractures at 50 years, compared with fractures in 35% (14/40) of non-venous stents tested to 1.4 years; no statistical testing was performed as durations do not match and the objective was to demonstrate the test method. The presented fatigue test method is a suitable approach for evaluating the durability of stents intended for venous use. Venous stents demonstrated superior fatigue resistance compared with non-venous stents via invitro hip flexion testing.

Structural optimization of degradable polymer vascular stents based on surrogate models

The clinical performance of biodegradable polymer stents implanted in blood vessels is affected by uneven degradation. Stress distribution plays an important role in polymer degradation, and local stress concentration leads to the premature fracture of stents. Numerical simulations combined with in vitro experimental validation can accurately describe the degradation process and perform structural optimization. Compared with traditional design techniques, optimization based on surrogate models is more scientifically effective. Three stent structures were designed and optimized, with the effective working time during degradation as the optimization goal. The finite element method was employed to simulate the degradation process of the stent. Surrogate models were employed to establish the functional relationship between the design parameters and the degradation performance. The proposed function models accurately predicted the degradation performance of various stents. The optimized stent structures demonstrated improved degradation performance, with the kriging model showing a better optimization effect. This study provided a novel approach for optimizing the structural design of biodegradable polymer stents to enhance degradation performance.

Melody transcatheter pulmonary valve replacement: a single-center case series in Southeast Asia

BackgroundStudies of transcatheter pulmonary valve replacement (TPVR) with the Melody valve have demonstrated good clinical and hemodynamic outcomes. Our study analyzes the midterm clinical and hemodynamic outcomes for patients who underwent Melody valve implantation in Southeast Asia.MethodsPatients with circumferential conduits or bioprosthetic valves and experiencing post-operative right ventricular outflow tract (RVOT) dysfunction were recruited for Melody TPVR.ResultsOur cohort (n = 14) was evenly divided between pediatric and adult patients. The median age was 19 years (8–38 years), a male-to-female ratio of 6:1 with a median follow-up period of 48 months (16–79 months), and the smallest patient was an 8-year-old boy weighing 18 kg. All TPVR procedures were uneventful and successful with no immediate mortality or conduit rupture. The primary implant indication was combined stenosis and regurgitation. The average conduit diameter was 21 ± 2.3 mm. Concomitant pre-stenting was done in 71.4% of the patients without Melody valve stent fractures (MSFs). Implanted valve size included 22-mm (64.3%), 20-mm (14.3%), and 18-mm (21.4%). After TPVR, the mean gradient across the RVOT was significantly reduced from 41 mmHg (10–48 mmHg) to 16 mmHg (6–35 mmHg) at discharge, p < 0.01. Late follow-up infective endocarditis (IE) was diagnosed in 2 patients (14.3%). Overall freedom from IE was 86% at 79 months follow-up. Three patients (21.4%) developed progressive RVOT gradients.ConclusionFor patients in Southeast Asia with RVOT dysfunction, Melody TPVR outcomes are similar to those reported for patients in the US in terms of hemodynamic and clinical improvements. A pre-stenting strategy was adopted and no MSFs were observed. Post-implantation residual stenosis and progressive stenosis of the RVOT require long term monitoring and reintervention. Lastly, IE remained a concern despite vigorous prevention and peri-procedural bacterial endocarditis prophylaxis.

Five-year outcomes of endovascular treatment for aortic dissection from the Global Registry for Endovascular Aortic Treatment

ObjectiveThe Global Registry for Endovascular Aortic Treatment (GREAT) is an International prospective multicenter registry collecting real-world data on performance of Gore aortic endografts. The purpose was to analyze the long-term outcomes and patient survival rates, as well as device performance in patients undergoing thoracic endovascular aortic repair for acute and chronic and complicated or uncomplicated type B aortic dissection (TBAD). MethodsFrom August 2010 to October 2016, 5014 patients were enrolled in the GREAT registry. The study population were patients treated with thoracic endovascular aortic repair for TBAD through 5-year follow-up (days 0-2006). The primary outcomes for this analysis were all-cause and aortic-related mortality, stroke, aortic rupture, endoleaks, migration, fracture, compression, and any reintervention through 5 years. ResultsWe identified 265 patients. The mean age was 60.9 ± 11.9 years (range, 19-84 years; 211 males [79.6%]). Devices used were the Gore TAG and Conformable Gore TAG Thoracic Endoprosthesis. There were 228 patients (86.0%) who underwent primary endovascular treatment (144 off-label [54.3%]); 22 (8.3%) underwent reintervention after prior endovascular procedure and 15 (5.7%) underwent reintervention after prior open procedure. Kaplan-Meier estimated freedom from all-cause mortality at 5 years was 71.1%. Freedom from aortic-related mortality through 5 years was 95.8%. There was no significant difference in freedom from all-cause mortality during the follow-up period in complicated or uncomplicated disease. At 30 days and through 5 years, respectively, for all the following outcomes, the aortic rupture rate was 1.1% (n = 3) and 1.9% (n = 5). The stroke rate was 1.1% (n = 3) and 4.2% (n = 11). The spinal cord ischemic event rate was 1.5% (n = 4) and 2.6% (n = 7). Reinterventions were required in 6.4% (n = 17) and 21.1% (n = 56) of patients. The need for conversion to open repair was 0.4% (n = 1) and 2.6% (n = 7). Additional graft placement was required in 3 patients (1.1%) and 16 patients (6.0%). The endoleak rate at 30 days was 3.4% (n = 9); type IA (n = 1 [0.4%]), type IB (n = 4 [1.5%]), type II (n = 1 [0.4%]), type III (n = 1 [0.4%]), and unspecified (n = 4 [1.6%]). Through 5 years, the endoleak rate was 12.1% (n = 32); type IA (n = 7 [2.6%]), type IB (n = 10 [3.8%]), type II (n = 9 [3.4%]), type III (n = 2 [0.8%]), and unspecified (n = 12 [4.5%]). There were no cases of stent migration, compression or fracture through 5 years. ConclusionsResults at the 5-year follow-up demonstrate that the use of the Gore TAG and Conformable Gore TAG Thoracic Endoprosthesis can be supported in treatment of TBAD (acute, chronic, complicated, and uncomplicated). These data demonstrate strong device durability, beneficial patient outcomes, and support for the treatment of thoracic aortic dissection with an endovascular approach. Complete 10-year follow-up in GREAT as planned will be advantageous.

Femoropopliteal Pseudoaneurysms as a Complication of Self-Expanding Nitinol Stent Fracture: A Brief Report and Review

Femoropopliteal Pseudoaneurysms as a Complication of Self-Expanding Nitinol Stent Fracture: A Brief Report and Review

B-7 | Balloon Dilation Technique Influences Stent Shortening and Intentional Stent Fracture During Over-Expansion of Drug-Eluting Stents: A Bench Testing Study

B-7 | Balloon Dilation Technique Influences Stent Shortening and Intentional Stent Fracture During Over-Expansion of Drug-Eluting Stents: A Bench Testing Study

Safety and Efficacy of Overdilation of 10 mm Viatorr Transjugular Intrahepatic Portosystemic Shunt Stents Using 12 mm Balloons

Abstract Objective The aim of this study was to evaluate overdilation of 10-mm standard and 8–10 mm controlled-expansion Viatorr stents to 12 mm during transjugular intrahepatic portosystemic shunt (TIPS) placement when insufficient reduction (&lt;50%) in portosystemic gradient (PSG) is achieved with standard 10 mm dilation. Materials and Methods It is a single-institution, institutional review board-approved, retrospective review of TIPS (2013–2022) to identify patients in the overdilation group (12 mm dilation of a 10-mm stent) and a control group (10 mm dilation of a 10-mm stent) matched for age, indication, stent type, Model for End-Stage Liver Disease (MELD) score, pre-TIPS PSG, and variceal embolization. Stent diameter, technical success, clinical outcomes, and adverse events were assessed for both groups. Results TIPS was created for the overdilation group (n = 35, 57 ± 11 years, 69% male; MELD: 14 ± 5) and control group (n = 35, 57 ± 11 years, 83% male; MELD: 14 ± 5). Overdilation to 12 mm adequately reduced PSG by more than 50% (55 vs. 65% in the control group, p = 0.11). The stent diameter was larger in the overdilation group on cross-sectional imaging (9.8 ± 0.2 vs. 9.5 ± 0.4 mm, p &lt; 0.001), with an estimated 57% higher volume flow rate (p = 0.002). Patients were followed for a median of 11.3 months (range: 0.03–75) and 15.6 months (range: 0.03–106) in the overdilation and control groups, respectively. There was an equivalent rate of ascites resolution (56 vs. 63%, p = 0.68) and rebleeding (13 vs. 17%, p = 0.82) in the overdilation and control groups, with a similar risk of new-onset hepatic encephalopathy (41 vs. 33%, p = 0.51) and TIPS occlusion (11 vs. 9%, p = 0.69). Overdilation did not result in any instance of stent fracture. Conclusion Overdilation of 10-mm Viatorr stents with 12 mm balloons may provide benefit by potentially reducing PSG further for patients initially having inadequate PSG reduction with short-term safety.

Evaluation of the efficacy of combined device strategies for long femoropopliteal artery disease.

One of the major problems associated with bare nitinol stent implantation is stent fracture, particularly in the popliteal artery. The purpose of this study was to determine whether drug coated balloons (DCB), interwoven stents (IWS), or plain old balloon angioplasty (POBA) would be suitable for use in distal femoropopliteal (FP) long lesions when an Eluvia stent was implanted proximal to a lesion. This was a multi-center retrospective study enrolling patients undergoing concomitant use of Eluvia with DCB, IWS or POBA for symptomatic atherosclerotic femoropopliteal disease (lesion length > 15cm) [Rutherford category 2-6] between January 2018 and September 2021. 79 patients with 89 femoropopliteal lesions were enrolled in this study. The mean lesion length and the percentage of the popliteal artery involvement was 24.3 ± 6.4cm vs 24.0 ± 9.0cm vs 26.6 ± 6.2cm and 65.8% vs 89.4% vs 67.8% for the Eluvia + DCB, Eluvia + IWS, and Eluvia + POBA groups, respectively. The 1-year Kaplan-Meier estimates of primary patency and freedom from major adverse limb events (MALEs) were 53.3% vs 44.1% vs 24.2% and 62.4% vs 51.0% vs 28.1%, respectively. Eluvia + POBA was associated with a lower rate for 1-year primary patency (HR 2.49; 95% confidence interval (CI): 1.28-4.87; p = 0.007 and HR 2.38; 95% CI: 1.13-5.77; p = 0.04). In SFA long lesions with proximal Eluvia implantation, distal implantations of either a DCB or IWS were comparable, as opposed to POBA alone which generated worse results.

Long-term outcomes of endovascular therapy for right subclavian artery occlusive lesions: A multi-center experience.

To review our multi-institutional experience with endovascular therapy for right subclavian artery occlusive disease and to evaluate the long-term outcomes. We retrospectively evaluated all patients with right subclavian artery stenosis and occlusive disease who underwent endovascular therapy between March 2014 and September 2022 at two institutions. Patient baseline demographics, lesion characteristics, treatment strategies, and in-hospital and follow-up outcomes were prospectively collected and retrospectively analyzed. Between March 2014 and September 2022, 73 patients underwent endovascular treatment at the two institutions. The dominant cause of lesions in this cohort was atherosclerosis. Three different types of lesions were summarized, and the corresponding endovascular strategies were performed. 66 patients (90.4%) underwent successful endovascular treatment, and 62 patients (84.9%) underwent balloon-expandable stent deployment. The mean perioperative in-hospital stay was 4.0days (range, 3-6days). Two patients died due to myocardial infarction, and one died of cerebral hemorrhage resulting from a traffic accident within 30days of the intervention. The median follow-up time was 31.6months (range, 12-96 months). No complications, including death, stroke, stent fractures, or migration, were noted in any patient during the follow-up period. The overall complication rate was 7/73 (9.6%), and 5/7 (6.9%) of the complications required reintervention. Endovascular treatment of right subclavian artery lesions is safe, effective, and technically achievable. The reasonable use of balloon-expandable stents can achieve satisfactory outcomes with accurate orientation and promising patency.

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

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. 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. 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). 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. 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.