Stenting Procedure Research Articles

Distal Arch Aneurysm Repair Using Left Subclavian Artery Transposition With Stented Elephant Trunk in the Hybrid Repair Era

Hybrid aortic arch repair is an invasive approach to the surgical management of distal aortic arch aneurysm. The complications associated with hybrid aortic arch repair, such as stroke and endoleaks, are not uncommon and late reintervention is frequent. We retrospectively reviewed our experience of distal aortic arch aneurysm repair using the stented elephant trunk procedure with left subclavian artery (LSCA)-left common carotid artery (LCCA) transposition in the hybrid repair era. Between May 2009 and September 2016, 19 patients with distal aortic arch aneurysm underwent LSCA-LCCA transposition with stented elephant trunk implantation under hypothermic cardiopulmonary bypass with selective antegrade cerebral perfusion. All patients were males with a median age of 51±14 (range 20-69) years. There were no in-hospital deaths. Continuous renal replacement therapy was not required in patients with preoperative renal dysfunction after surgery. No neurologic deficits were observed in any patients prior to hospital discharge. One patient underwent concomitant thoracic endovascular aortic repair after this technique. One case required reoperation due to bleeding. One patient required debridement due to poor wound healing. During a mean follow-up of 33±21months, one patient died. Satisfactory results were obtained in suitable patients undergoing surgery for distal aortic arch aneurysm using LSCA-LCCA transposition with stented elephant trunk implantation in the hybrid repair era. The straightforward nature of the surgical approach, with avoidance of the complications related to hybrid aortic arch repair and reduction of late re-intervention favours this technique for treating distal aortic arch aneurysm.

Abstract No. 642 Does timing of radiation treatment affect endovascular stenting procedure parameters in the treatment of SVC syndrome?

Abstract No. 642 Does timing of radiation treatment affect endovascular stenting procedure parameters in the treatment of SVC syndrome?

The application of the screen-model based approach for stents in cerebral aneurysms

Numerical modeling of the blood flow through flow diverters in intracranial aneurysms is a crucial tool to personalize and optimize endovascular stenting procedures in the treatment of aneurysms. However, large computational meshes are needed to resolve the difference of scale between the struts of a flow diverter and the blood vessel leads, leading to a high computational cost. This article presents a screen-model based approach, a heuristic continuum method which can effectively reduce the computation time by avoiding to fully resolve the stent. We study the performance of the screen-model based stent model under various conditions, such as different stent placements inside an artery, varying homogeneous porosities, and pulsatile inlet velocities. The results show that the stent model can effectively prevent the blood from flowing into the aneurysm as a fully resolved stent does, but at a coarser resolution. The application range of the stent model is tested, and the validity of the model is assessed.

Ten-year experience of the thoraco-abdominal aortic aneurysm treatment using a hybrid thoracic endovascular aortic repair.

The treatment of thoraco-abdominal aortic aneurysm continues to have a high mortality and paraplegia rate. In superaging societies, the methods of performing less invasive operations remain a major issue. We reviewed our 10-year experience in the treatment of thoraco-abdominal aortic aneurysm using a hybrid procedure of combined visceral reconstruction and thoracic endovascular aortic repair. Sixty patients underwent a hybrid repair for the treatment of the thoraco-abdominal aortic aneurysm between 2007 and 2016. The mean age was 72.7 years. A true aneurysm was found in 43 (72%) patients and a chronic dissection in 17 (28%) patients. The standard operative procedure involved replacing the abdominal aorta with an artificial graft, and the visceral arteries were reconstructed using a quadrifurcated graft. Renovisceral debranching and stent grafting were performed as a 2-stage procedure. The hospital mortality rate was 5%. Two (3%) patients died due to an aneurysmal rupture in the hospital just after renovisceral debranching. The other 2 patients died due to an aneurysmal rupture in the long-term period after preventive renovisceral debranching. Two (3%) patients experienced spinal cord ischaemia after the stenting procedure. Four (7%) patients required additional treatment during the follow-up period. The overall survival was 75.9% at 2 years, 65.2% at 5 years and 43.5% at 8 years. The rates of freedom from aorta-related events were 92.9% at 2 years, 80.5% at 5 years and 72.5% at 8 years. The hybrid repair is considered to be a good option for elderly and high-risk patients. Further long-term follow-up is necessary to extend the indication in younger patients.

Model for pressure drop and flow deflection in the numerical simulation of stents in aneurysms.

The numerical simulation of flow diverters like stents contributes to the development and improvement of endovascular stenting procedures, leading ultimately to an improved treatment of intracranial aneurysms. Due to the scale difference between the struts of flow diverters and the full artery, it is common to avoid fully resolved simulations at the level of the stent porosity. Instead, the effect of stents on the flow is represented by a heuristic continuum model. However, the commonly used porous media models describe the properties of flow diverters only partially, because they do not explicitly account for the deflection of the flow direction by the stent. We show that this deficiency can be circumvented by adopting the theoretical framework of screen models. The article first reviews existing screen models. It then proposes an explicit formula for the drag and the deflection coefficient, as predicted by each model, for both perpendicular and inclined angles. The results of 2D numerical simulations are used to formulate a generalization of these formulas, to achieve best results in the case of stent modeling. The obtained model is then validated, again through 2D numerical simulation.

Safety and efficacy of oesophageal stenting with simultaneous percutaneous endoscopic gastrostomy as a supplementary feeding route in unresectable proximal oesophageal cancer.

IntroductionProximally located oesophageal cancer poses an especially difficult problem in terms of restoration of patency and the stenting procedure. Supplementary percutaneous endoscopic gastrostomy (PEG) may be useful in these patients.AimTo assess the safety of the stenting procedure in the proximal oesophagus in patients with unresectable upper oesophageal cancer, performed simultaneously with PEG insertion.Material and methodsPatients with obstructing upper oesophageal tumours were scheduled for an oesophageal stenting procedure and simultaneous PEG insertion. Degree of dysphagia, body weight loss, daily energy requirement, body mass index and performance status before and after the stenting procedure as well as complications were assessed.ResultsForty-five patients aged 19–88 years were included in the study. Six of them had a fistula to the trachea and underwent stenting of the oesophagus or both the oesophagus and the airway. The technical success rate was 100%. Following the procedure all patients were able to swallow fluids and semi-liquids, and PEG was used as the primary feeding route. Body mass index increased from 20.4 to 21.1 (p = 0.0001), body weight gain improved from –10.1 to +2.0 kg and metabolic requirements improved (p = 0.0001). Also, the Karnofsky score improved significantly (56.7 vs. 65.1, p = 0.0001). Mean survival time was 133 days (range: 36–378).ConclusionsStenting of the proximal oesophagus with simultaneous PEG is a safe procedure, allowing the patients to resume oral intake of liquids whilst improving nutritional status and general performance, with an acceptable rate of complications.

Carotid Near-Occlusion Stent Experiences.

Treatment strategy for near-occlusions (NO) of the internal carotid artery (ICA) is still controversial. In this study, we aimed to present the clinical results of stent placement in 50 patients with carotid artery (NO) stenosis that presented to our center, and upon which revascularization will be performed. Between 2014 and 2017, 50 patients with (NO) from 180 patients who had stents in the Interventional Vascular Neurology clinic were retrospectively studied. All the patients whether using or not using the proximal and distal protection device during the procedure were included. Patients had clinical neurologic evaluation, and underwent carotid artery radiologic imaging before the carotid artery stent (CAS) procedure. Balloon dilatation was applied before the stent procedure for patients that had advanced stenosis. Post-dilatation was applied with a balloon of appropriate size in case of residual narrowing. Findings such as bradycardia, hypotension, reperfusion hemorrhage during and after the stent placement procedure, as well as patients that developed restenosis within 12 months were recorded. This study includes 50 (30 males, 20 females) patients that underwent carotid stent placement. The mean age of patients was 65 (28-81). Reperfusion hemorrhage was seen in 1 (2%) patient and the patient died in week 3. Ten (20%) patients complained of chills and tremor lasting less than 3 hours after the procedure. One (2%) patient had encephalopathy and agitation for less than 24 hours. Two (4%) patients had hypotension, and 15 (30%) patients had a headache for less than 24 hours. Three patients developed local hematoma at the site of the sheath, and were treated by applying compression. Restenosis signs in the stent site was observed in 6 patients (12%) in color Doppler ultrasonography of the carotid performed in the 6th and 12th months. Although the innate process of ICA NO is not well known, it might be more frequent than currently considered. Especially after the diagnosis of ICA stenosis, it is important to make the right diagnosis in patients that have new ipsilateral symptoms. After the diagnosis is made, CAS, when performed by an experienced neuro-interventional team, seems beneficial with low complication rates.

An Unusual Cause of Acute Heart Failure: A Case Report of Iliocaval Venous Stent Migration.

Stent migration is an uncommon complication of endovascular stenting procedures. It could cause serious cardiovascular complications. In this article, we describe an interesting case of acute heart failure as a result of stent embolization from the left common iliac vein into the right ventricle and how it was identified and managed.

Transradial Stenting for Carotid Stenosis in Patients with Bovine Type and Type III Aortic Arch: Experience in 28 Patients.

The effects and safety of transradial access for stenting of carotid artery stenosis in patients with bovine-type and type III aortic arch are currently unknown and are the purpose of this study. Patients who were treated with stenting via transradial (n= 28) compared with transfemoral (n= 30) access of carotid artery stenosis complicated with bovine-type and type III aortic arch were enrolled. The clinical data were studied for comparison. The success rate of transradial access for carotid artery stenting was 100%. During the transradial access procedure, 3 patients experienced a temporary blood pressure drop and bradycardia that was resolved with atropine injection. No radial artery occlusion or severe cardiac or cerebral events occurred. The success rate of transfemoral access for carotid artery stenting was 90% with failure in 3 patients. No complications occurred during or after the stenting procedure. The irradiation duration was significantly (P= 0.001) smaller in transradial than in transfemoral access stenting (8.6 ± 0.87 vs. 11.4 ± 1.25 minutes). The arterial stenosis ranged 71.25%-96.50% (mean, 86.50% ± 10.15%) for transradial and 78%-97.75% (85.1% ± 10.42%) for transfemoral access groups before treatment, and the residual stenosis following treatment was significantly smaller in either the transradial (2.4%-17.75%; mean, 11.2% ± 6.03%) or transfemoral (4%-18.6%; mean, 12.4% ± 6.3%) groups compared with before treatment, respectively. The transradial access for stenting of patients with type III aortic arch plus left carotid artery stenosis or in the bovine-type aortic arch combined with right carotid artery stenosis can decrease the stenting difficulty, risks of embolization, and radiation time and increase the success rate.

The repair of a type Ia endoleak following thoracic endovascular aortic repair using a stented elephant trunk procedure

BackgroundType Ia endoleaks are not uncommon complications that occur after thoracic endovascular aortic repair (TEVAR). Because aortic arch vessels prevent extension of the landing zone, it is very difficult to manipulate a type Ia endoleak using an extension cuff or stent-graft, especially when the aortic arch is involved. Here, we retrospectively review our experience of surgical treatment of type Ia endoleak after TEVAR using a stented elephant trunk procedure. MethodsFrom July 2010 to August 2016, we treated 17 patients diagnosed with a type Ia endoleak following TEVAR using stented elephant trunk procedure. The mean age of our patients was 52 ± 8 years. The mean interval between TEVAR and the open surgical repair was 38 ± 43 months. ResultsAll cases of type Ia endoleak (100%) were repaired successfully. There were no in-hospital deaths. One case required reintubation and continuous renal replacement therapy due to renal failure; this patient recovered smoothly before discharge. One other patient suffered a stroke and renal failure and did not fully recover following discharge, or follow-up. During follow-up, there were 3 deaths. ConclusionsAcceptable results were obtained using a stented elephant trunk procedure in patients with a type Ia endoleak after TEVAR. This technique allowed us to repair the proximal aortic arch lesions, surgically correct the type Ia endoleak, and promote false lumen thrombosis in the distal aorta. Implantation of a stented elephant trunk, with or without a concomitant aortic arch procedure, is an alternative approach for this type of lesion.

Self-expandable metallic stent application for the management of upper gastrointestinal tract disease.

The aim of the present study was to share our experiences of the use of self-expandable metallic stent for the upper gastrointestinal tract disease. We retrospectively reviewed the medical records of 18 patients who underwent self-expandable metallic stent implantation procedure for anastomosis stricture, anastomosis leak, or spontaneous fistula of the upper gastrointestinal tract at two different surgery clinics. Self-expandable metallic stent implantation procedures were performed while keeping the patient under sedation and the correct stent localization was verified using fluoroscopy. The stent localization and possible stent migration were checked using X-ray films taken a few days after the stenting procedure. Overall, 25 self-expandable metallic stents were implanted in 18 patients (malignant, 13; benign, 5) aged between 19 and 89 years. The indications for self-expandable metallic stent implantation were as follows: malignant gastric stricture (inoperable; n=6), malignant esophageal stricture (inoperable; n=4), staple line leak (laparoscopic sleeve gastrectomy; n=4), esophagojejunostomy anastomotic leak (total gastrectomy+Roux-en-Yesophagojejunostomy; n=2), and stricture (total gastrectomy+Roux-en-Yesophagojejunostomy; n=1), and esophagopleural fistula (pulmonary tuberculosis; n=1). A favorable outcome was achieved in a single session in 15 patients, whereas more than two sessions of stenting were necessary in the remaining three patients. Among the patients who underwent esophagojejunal anastomosis (n=3), self-expandable metallic stents were successfully deployed in a single session in two patients to relieve anastomosis leak (n=1) and anastomosis stricture (n=1); the remaining patients underwent four self-expandable metallic stent implantation procedures to relieve anastomosis leak and subsequent recurrent strictures. No complications developed during the stenting procedure. Three of the four patients who developed mortality had advanced stage esophageal cancer, whereas one patient had morbid obesity and developed staple line leakage. Endoscopic self-expandable metallic stent implantation under fluoroscopic guidance is a low-morbidity and effective procedure for the management of advanced stage tumors of the gastrointestinal tract and the elimination of postoperative complications.

The Role of Hemodynamics in Intracranial Bifurcation Arteries after Aneurysm Treatment with Flow-Diverter Stents.

Treatment of intracranial bifurcation aneurysms with flow-diverter stents can lead to caliber changes of the distal vessels in a subacute phase. This study aims to evaluate whether local anatomy and flow disruption induced by flow-diverter stents are associated with vessel caliber changes in intracranial bifurcations. Radiologic images and demographic data were acquired for 25 patients with bifurcation aneurysms treated with flow-diverter stents. Whisker plots and Mann-Whitney rank sum tests were used to evaluate if anatomic data and caliber changes could be linked. Symmetry/asymmetry were defined as diameter ratio 1 = symmetric and diameter ratio <1 = asymmetric. Computational fluid dynamics was performed on idealized and patient-specific anatomies to evaluate flow changes induced by flow-diverter stents in the jailed vessel. Statistical analysis identified a marked correspondence between asymmetric bifurcation and caliber change. Symmetry ratios were lower for cases showing narrowing or subacute occlusion (medium daughter vessel diameter ratio = 0.59) compared with cases with posttreatment caliber conservation (medium daughter vessel diameter ratio = 0.95). Computational fluid dynamics analysis in idealized and patient-specific anatomies showed that wall shear stress in the jailed vessel was more affected when flow-diverter stents were deployed in asymmetric bifurcations (diameter ratio <0.65) and less affected when deployed in symmetric anatomies (diameter ratio ∼1.00). Anatomic data analysis showed statistically significant correspondence between caliber changes and bifurcation asymmetry characterized by diameter ratio <0.7 (P < .001). Similarly, computational fluid dynamics results showed the highest impact on hemodynamics when flow-diverter stents are deployed in asymmetric bifurcations (diameter ratio <0.65) with noticeable changes on wall sheer stress fields. Further research and clinical validation are necessary to identify all elements involved in vessel caliber changes after flow-diverter stent procedures.

Endoscopic ultrasound-guided gallbladder drainage for acute cholecystitis with a silicone-covered nitinol short bilaterally flared stent: a case series.

Background and study aim Gallbladder drainage in patients with cholecystitis who are unsuitable for surgery may be performed by endoscopic ultrasound (EUS)-guided placement of specifically designed fully covered metal stents. We describe the first case series of patients treated with a silicone-covered nitinol stent with bilateral anchor flanges. Patients and methods Data from consecutive patients with acute cholecystitis who were deemed unsuitable candidates for surgery were collected. The stent placement procedure was performed in two tertiary endoscopy centers by four experienced endoscopists. Technical and clinical success rates, as well as adverse events and clinical outcome at follow-up, were assessed. Results EUS-guided drainage for cholecystitis was performed in 16 patients (mean age 84 years; nine males). Technical and clinical success rates were 100 % (16/16) and 94 % (15/16), respectively; an early failure due to stone impaction occurred in the remaining case and required placement of a new stent. Symptom relief occurred in 11/15 cases (73 %) within 1 day, and within 2 days in the remaining 4 patients. Bleeding occurred in two patients (13 %): in one patient intraprocedural bleeding was successfully stopped during endoscopy; and delayed bleeding occurred in one patient requiring arterial embolization for catastrophic bleeding (patient died 10 days later). No cases of cholecystitis recurrence or biliary obstruction were observed during a median follow-up of 112 days (range 49 – 180 days). Conclusions Our data showed that EUS-guided gallbladder drainage with a specially designed stent is feasible and successful in patients with acute cholecystitis who are unfit for surgery.

Risk factors for urological complications following living donor renal transplantation in children.

The aim of this study was to detect possible risk factors for UC and UTI following pediatric renal Tx and effect of these complications on outcome. One hundred and eight children who underwent living donor Tx between 2009 and 2015 were retrospectively included. Extraperitoneal approach was used with stented tunneled extravesical procedure. Mean recipient age was 9.89±3.46years while mean weight was 25.22±10.43kg. Seventy-three (67.6%) recipients were boys while 92 (85.2%) were related to donors. Urological causes of ESRD were present in 33 (30.6%) recipients (14 [13%] posterior urethral valve, 16 [14.8%] VUR, and 3 [2.8%] neurogenic bladder). Augmentation ileocystoplasty was performed in 9 (8.3%) patients. Mean follow-up was 39.3±17.33months. UC were detected in 10 (9.3%) children (leakage 4 [3.7%], obstruction 3 [2.8%], and VUR 3 [2.8%]) while UTIs were reported in 40 (37%) children. After logistic regression analysis, UC were significantly higher in children with cystoplasty (44.4% vs 6.1%; P=.001). UTIs were significantly higher in girls (51.4% vs 30.1%; P=.001) and in children with urological causes of ESRD (51.5% vs 30.7%; P=.049). UC and UTI were not significantly associated with increased graft loss or mortality. UC were significantly higher in children with cystoplasty while UTIs were significantly higher in girls and children with urological causes of ESRD. Presence of UC did not affect the rate of graft loss or mortality due to its early detection and proper management.

Experimental Bench for Hemodynamic Study of Coronary Artery with Serial Stenoses: Fractional Flow Reserve Assessment

The measurement of Fractional Flow Reserve (FFR) becomes essential for an interventional cardiologist to decide whether or not an angioplasty or stenting procedure needs to be performed on his pati...

Stent boost enhancement compared to intravascular ultrasound in the evaluation of stent expansion in elective percutaneous coronary interventions

BackgroundStent underexpansion is a major risk factor for in-stent restenosis and acute in-stent thrombosis1Intravascular ultrasound (IVUS) is one of the standards for detection of stent underexpansion (de Feyter et al. 1999; Mintz et al., 2001). StentBoost (SB) enhancement allows an improved angiographic visualization of the stent (Koolen et al., 2005).Aim of workComparison of stent expansion by IVUS and SB enhancement and detection of value of SB to guide dilatation post stent deployment.MethodologyIVUS, SB enhancement and QCA were done in 30 patients admitted for elective stenting procedures .We compared measurements of mean ±standard deviations of (Max SD, Min SD, Mean SD, stent symmetry index) using IVUS, SB and QCA after stent deployment and after postdilatation whenever necessary to optimize stent deployment. The Stent symmetry index was calculated [(maximum stent diameter minus minimum stent diameter) divided by maximum stent diameter].ResultsThe Max SD was (3.45 ± 0.62 vs 3.55 ± 0.56 vs 2.97 ± 0.59) by IVUS vs SB vs QCA respectively. Max SD was significantly higher by IVUS vs QCA (p .009) and between SB vs QCA (p .001) while there was nonsignificant difference between IVUS vs SB (p .53). The Min SD was (2.77 ± 0.53 vs 2.58 ± 0.56 vs 1.88 ± 0.60) by IVUS vs SB vs QCA respectively. Min SD was significantly higher by IVUS vs QCA (p .001) and between SB vs QCA (p .001) while there was nonsignificant difference between IVUS vs SB (p .07). The stent symmetry index was (0.24 ±0.09 vs 0.34 ± 0.09 vs 0.14 ±0.27) by IVUS vs SB vs QCA respectively. It was significantly higher by IVUS vs QCA (p .001) and between SB vs QCA (p .001) while there was nonsignificant difference between IVUS vs SB (p .32). SB was positively correlated with IVUS measurements of Max SD (p < .0001 & r 0.74) and Min SD (p < .0001 & r 0.68). QCA was positively correlated with IVUS measurements of Max SD correlation (p < .0001 & r 0.69) and Min SD (p < .0001 & r 0.63). QCA was positively correlated with SB measurements of Max SD (p < .0001 & r 0.61) and Min SD (p .003 & r 0.49).ConclusionsStentBoost enhancement has superior correlations for stent expansion measured by IVUS when compared with QCA. SB enhancement improved stent visualization and identification of stent underexpansion to guide stent postdilatation.

Optical coherence tomography guided carotid artery stent procedure: technique and potential applications

To (1) present a guide on how to perform optical coherence tomography (OCT) in carotid artery stenting (CAS), to (2) highlight several instructive cases illustrating OCT-guidance as an interventional strategy, and to (3) present the largest case-series of OCT-guided CAS performed in North America, demonstrating its feasibility as an imaging modality in this setting. OCT is an intravascular imaging method that captures images with an axial resolution 10 times higher than intravascular ultrasound. OCT has proven to be a useful modality in coronary angiography and may have similar applications in evaluating carotid atherosclerotic disease. We compared our experience in CAS utilizing OCT (40 patients) versus that of CAS without OCT guidance (52 patients). No strokes or deaths occurred in either group postprocedurally or at 12 months. Fluoroscopy time was reduced in the OCT arm (14 ± 1 vs. 16 ± 1 min). Postprocedural creatinine levels were identical (1 ± 0 mg/dl, P = 0.96). Procedure time (96 ± 8 vs. 80 ± 3 min, P = 0.06) and contrast use (94 ± 4 vs. 83 ± 4 ml, P = 0.05) was slightly elevated in the OCT arm. We established a standardized protocol to consistently obtain OCT images that helped guide interventional decision-making during CAS. OCT imaging in the carotids requires a higher contrast load and prolongs procedure time. However, it can be performed without significant increases in fluoroscopy time or negatively affecting renal function. There were no negative safety signals in this pilot study.

Association of Quality Improvement Registry Participation With Appropriate Follow-up After Vascular Procedures

ImportanceEnsuring that patients undergo surveillance imaging after surgery is a key quality metric after many vascular procedures. It is unclear whether hospital participation in a national quality improvement registry such as the Vascular Quality Initiative (VQI) achieves this goal.ObjectiveTo determine if hospital participation in the VQI registry is associated with increased rates of surveillance imaging after vascular procedures.Design, Setting, and ParticipantsA quasi-experimental study used Medicare claims to study 2174 US hospitals in which 1 530 102 patients had undergone an endovascular abdominal aortic aneurysm repair (EVAR), 1 403 067 patients had undergone a lower extremity bypass (LEB) or peripheral vascular intervention (PVI), and 294 942 patients had undergone carotid endarterectomy (CEA) and carotid artery stenting (CAS) procedures between January 1, 2007, and December 31, 2012. For each hospital, VQI participation was assessed, and a difference-in-differences analysis was used to measure the change in follow-up surveillance for VQI hospitals compared with control (non-VQI) hospitals selected after propensity score matching. The data were analyzed between January and August of 2016.Main Outcomes and MeasuresThe proportion of patients who had imaging-based follow-up (computed tomography, duplex ultrasonography, or ankle-brachial index) within 1 year after their vascular procedure.ResultsA total of 1 830 928 patients (947 139 women and 883 789 men; mean [SD] age, 75.8 [7.1] years) were identified across 2174 hospitals. Of 3 228 111 total vascular procedures, 1 403 067 patients (43.5%) underwent LEB or PVI, 1 530 102 patients (47.4%) underwent EVAR, and 294 942 patients (9.1%) underwent CEA or CAS. During the 6-year period, follow-up imaging rates varied between 50% and 53% after EVAR, between 52% and 58% after LEB or PVI, and between 74% and 78% after CEA or CAS. A total of 68 VQI participating hospitals were propensity-matched to 68 hospitals, and 279 446 patients were studied across these 136 hospitals. In difference-in-differences analyses, there was no significant improvement in follow-up imaging after joining VQI during year 1 (relative risk, 0.99; 95% CI, 0.97-1.01), year 2 (relative risk, 0.98; 95% CI, 0.95-1.01), or year 3 (relative risk, 0.99; 95% CI, 0.96-1.03). This association was consistent for patients undergoing EVAR, LEB or PVI, and CEA or CAS procedures.Conclusions and RelevanceHospital participation in the VQI registry by itself does not increase rates of surveillance imaging after vascular procedures, suggesting that other strategies are needed to achieve this quality metric.

Biodegradable Magnesium Stent Treatment of Saccular Aneurysms in a Rat Model - Introduction of the Surgical Technique

The steady progess in the armamentarium of techniques available for endovascular treatment of intracranial aneurysms requires affordable and reproducable experimental animal models to test novel embolization materials such as stents and flow diverters. The aim of the present project was to design a safe, fast, and standardized surgical technique for stent assisted embolization of saccular aneurysms in a rat animal model. Saccular aneurysms were created from an arterial graft from the descending aorta.The aneurysms were microsurgically transplanted through end-to-side anastomosis to the infrarenal abdominal aorta of a syngenic male Wistar rat weighing >500 g. Following aneurysm anastomosis, aneurysm embolization was performed using balloon expandable magnesium stents (2.5 mm x 6 mm). The stent system was retrograde introduced from the lower abdominal aorta using a modified Seldinger technique. Following a pilot series of 6 animals, a total of 67 rats were operated according to established standard operating procedures. Mean surgery time, mean anastomosis time, and mean suturing time of the artery puncture site were 167 ± 22 min, 26 ± 6 min and 11 ± 5 min, respectively. The mortality rate was 6% (n=4). The morbidity rate was 7.5% (n=5), and in-stent thrombosis was found in 4 cases (n=2 early, n=2 late in stent thrombosis). The results demonstrate the feasibility of standardized stent occlusion of saccular sidewall aneurysms in rats - with low rates of morbidity and mortality. This stent embolization procedure combines the opportunity to study novel concepts of stent or flow diverter based devices as well as the molecular aspects of healing.

Biodegradable Magnesium Stent Treatment of Saccular Aneurysms in a Rat Model - Introduction of the Surgical Technique.

The steady progess in the armamentarium of techniques available for endovascular treatment of intracranial aneurysms requires affordable and reproducable experimental animal models to test novel embolization materials such as stents and flow diverters. The aim of the present project was to design a safe, fast, and standardized surgical technique for stent assisted embolization of saccular aneurysms in a rat animal model. Saccular aneurysms were created from an arterial graft from the descending aorta.The aneurysms were microsurgically transplanted through end-to-side anastomosis to the infrarenal abdominal aorta of a syngenic male Wistar rat weighing >500 g. Following aneurysm anastomosis, aneurysm embolization was performed using balloon expandable magnesium stents (2.5 mm x 6 mm). The stent system was retrograde introduced from the lower abdominal aorta using a modified Seldinger technique. Following a pilot series of 6 animals, a total of 67 rats were operated according to established standard operating procedures. Mean surgery time, mean anastomosis time, and mean suturing time of the artery puncture site were 167 ± 22 min, 26 ± 6 min and 11 ± 5 min, respectively. The mortality rate was 6% (n=4). The morbidity rate was 7.5% (n=5), and in-stent thrombosis was found in 4 cases (n=2 early, n=2 late in stent thrombosis). The results demonstrate the feasibility of standardized stent occlusion of saccular sidewall aneurysms in rats - with low rates of morbidity and mortality. This stent embolization procedure combines the opportunity to study novel concepts of stent or flow diverter based devices as well as the molecular aspects of healing.