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Sample records for culotte stenting procedure

  1. A Pilot Study on Culottes versus Crossover Single Stenting for True Coronary Bifurcation Lesions

    PubMed Central

    Zhang, Linlin; Zhong, Wenliang; Luo, Yukun; Chen, Lianglong

    2016-01-01

    Background The purpose of our study was to compare clinical and angiographic outcomes of planned culottes technique with that of provisional crossover single stenting in the treatment of true coronary bifurcation lesions (CBL) with drug-eluting stent (DES). Methods True CBL patients (n = 104) were randomly assigned to either the provisional stenting of the side branch (crossover group) or the culottes group. Additional side branch (SB) stenting in the crossover group was required if there was thrombolysis in myocardial infarction flow ≤ 1 flow). The primary end point was the occurrence of major adverse cardiac events (MACE) at nine months, including cardiac death, myocardial infarction, target lesion/vessel revascularization and in-stent thrombosis. The secondary end point was angiographic in-segment restenosis at nine months. Results The rate of MACE at nine months was similar between the crossover and culottes groups (7.7% vs. 7.7%, p = 1.000). Additional SB stenting in the crossover group was required in 3.8% of patients. There was one procedural occlusion of SB in the crossover group. At nine months, the rate of in-segment restenosis was similar in the parent main vessel (0% vs. 1.9%, p = 1.000), main branch (1.9% vs. 7.7%, p = 0.363) and SB (17.3% vs. 9.6%, p = 0.250) between the crossover and culottes groups, respectively. Conclusions This study demonstrated that there is no significant difference in cumulative MACE or in-segment restenosis between crossover and culottes groups. Larger randomized clinical trials are warranted to re-evaluate the outcomes of the provisional crossover stenting versus the culottes stenting techniques utilizing DES for true CBL. PMID:27471358

  2. Technical aspects of the culotte technique.

    PubMed

    Erglis, Andrejs; Lassen, Jens Flensted; Di Mario, Carlo

    2015-01-01

    The culotte technique provides near perfect coverage of the carina and side branch ostium at the expense of an excess of metal covering the proximal end. It can be used in almost all true bifurcation lesions, but should be avoided in bifurcations when there is a large mismatch between the proximal main branch and the side branch diameters. The main disadvantage of this technique is that rewiring of both branches through the stent struts is required, which can be difficult, technically demanding, and time-consuming.

  3. What to Expect After a Stent Procedure

    MedlinePlus

    ... insertion site Common Precautions After a Stent Procedure Blood Clotting Precautions After a stent procedure, your doctor will likely recommend that you take aspirin and another anticlotting medicine. These medicines help prevent blood clots from forming in the stent. A blood ...

  4. Stenting Procedure for Sinus Stenosis with Transverse-Sigmoid Dural Arteriovenous Fistulas

    PubMed Central

    Fukumoto, S.; Ueda, T.; Igase, K.; Ohue, S.; Kumon, Y.; Ohnishi, T.

    2006-01-01

    Summary We reported the dural AVF case with sinus stenosis, that was entirely treated through the stenting procedure. 61-year-old male had been realizing the attack which causes bilateral visual problem. He would have suffered from the intracranial hypertension caused by dural AVF in the right transverse sinus and left transverse sinus stenosis. We performed TVE and sinus stenting, then used the antiplatelet and the anticoagulant. However, six months later, he suffered from SAH due to recurrence of dural AVF. We performed TVE again, denser packing than usual. Two years later, he have no symptom, angiographically, there was no recurrence of dural AVF and patency of stented sinus. We think denser embolizations should have performed in case of dural AVF with sinus stenting. PMID:20569627

  5. Covered Stents in the Treatment of Peripheral Arterial Aneurysms: Procedural Results and Midterm Follow-Up

    SciTech Connect

    Beregi, Jean-Paul; Prat, Alain; Willoteaux, Serge; Vasseur, Marc-Antoine; Boularand, Valerie; Desmoucelle, Frederic

    1999-01-15

    Purpose: To evaluate initial and midterm results of percutaneous treatment of peripheral aneurysms using covered stents. Methods: Between June 1994 and December 1997 we used covered stents (EndoPro System or Passager) on 19 patients with peripheral aneurysms (7 iliac, 5 subclavian, 3 femoral, 3 popliteal, 1 carotid). Results: Successful aneurysm exclusion was achieved in 18 of 19 patients (95%). In the short term (<30 days), one patient died of puncture site hemorrhage complicated by myocardial infarction; two femoral stents were surgically removed because of leakage. At subsequent follow-up (mean 20 months) two further unrelated deaths occurred. At 1 year (intention-to-treat) the stent was patent in 13 of 19 patients (68%) and the aneurysm was excluded in 17 of 19 (89%). Conclusion: Treatment of peripheral aneurysms with covered stents has a high rate of immediate procedural success. Continued exclusion of the aneurysms is achieved in a large proportion of patients but there is a relatively high rate of stent thrombosis.

  6. Endoscopic multiple metal stenting for the treatment of enteral leaks near the biliary orifice: A novel effective rescue procedure

    PubMed Central

    Mutignani, Massimiliano; Dioscoridi, Lorenzo; Dokas, Stefanos; Aseni, Paolo; Carnevali, Pietro; Forti, Edoardo; Manta, Raffaele; Sica, Mariano; Tringali, Alberto; Pugliese, Francesco

    2016-01-01

    Between April 2013 and October 2015, 6 patients developed periampullary duodenal or jejunal/biliary leaks after major abdominal surgery. In all patients, percutaneous drainage of the collection or re-operation with primary surgical repair was attempted at first but failed. A fully covered enteral metal stent was placed in all patients to seal the leak. Subsequently, we cannulated the common bile duct and, in some cases, and the main pancreatic duct inserting hydrophilic guidewires through the stent after dilating the stent mesh with a dilatation balloon or breaking the meshes with Argon Plasma Beam. Finally, we inserted a fully covered biliary metal stent to drain the bile into the lumen of the enteral stent. In cases of normal proximal upper gastrointestinal anatomy, a pancreatic plastic stent was also inserted. Oral food intake was initiated when the abdominal drain outflow stopped completely. Stent removal was scheduled four to eight weeks later after a CT scan to confirm the complete healing of the fistula and the absence of any perilesional residual fluid collection. The leak resolved in five patients. One patient died two days after the procedure due to severe, pre-existing, sepsis. The stents were removed endoscopically in four weeks in four patients. In one patient we experienced stent migration causing small bowel obstruction. In this case, the stents were removed surgically. Four patients are still alive today. They are still under follow-up and doing well. Bilio-enteral fully covered metal stenting with or without pancreatic stenting was feasible, safe and effective in treating postoperative enteral leaks near the biliopancreatic orifice in our small series. This minimally invasive procedure can be implemented in selected patients as a rescue procedure to repair these challenging leaks. PMID:27606045

  7. Symptomatic stent cast.

    PubMed

    Keohane, John; Moore, Michael; O'Mahony, Seamus; Crosbie, Orla

    2008-02-01

    Biliary stent occlusion is a major complication of endoscopic stent insertion and results in repeat procedures. Various theories as to the etiology have been proposed, the most frequently studied is the attachment of gram negative bacteria within the stent. Several studies have shown prolongation of stent patency with antibiotic prophylaxis. We report the case of stent occlusion from a cast of a previously inserted straight biliary stent; a "stent cast" in an 86-year-old woman with obstructive jaundice. This was retrieved with the lithotrypter and she made an uneventful recovery. This is the first reported case of a biliary stent cast.

  8. iStent as a Solo Procedure for Glaucoma Patients: A Systematic Review and Meta-Analysis

    PubMed Central

    Malvankar-Mehta, Monali S.; Chen, Yufeng Nancy; Iordanous, Yiannis; Wang, Wan Wendy; Costella, John; Hutnik, Cindy M. L.

    2015-01-01

    Background Glaucoma is a leading cause of irreversible blindness. It is firmly entrenched in the traditional treatment paradigm to start with pharmacotherapy. However, pharmacotherapy is not benign and has been well documented to have a number of significant challenges. Minimally invasive glaucoma surgery (MIGS) that targets the outflow pathway with minimal to no scleral dissection has resulted in the need to reconsider the glaucoma treatment paradigm. Purpose To perform a systematic review and meta-analysis to evaluate and quantify the effect on post-operative intraocular pressure (IOP) and number of topical glaucoma medications, in patients receiving the iStent MIGS device as the solo procedure without concurrent cataract surgery. Methods A systematic review was conducted by searching various databases between January 1, 2000, and June 30, 2014. Studies reporting up to a maximum follow-up period of 24 months were retrieved and screened using the EPPI-Reviewer 4 gateway. Percentage reduction in IOP (IOPR%), and mean reduction in topical glaucoma medications after surgery were computed. Meta-analysis was performed using STATA v. 13.0. The standardized mean difference (SMD) was calculated as the effect size for continuous scale outcomes. Heterogeneity was determined using the I2 statistics, Z-value, and χ2 statistics. Fixed-effect and random-effect models were developed based on heterogeneity. Sub-group analysis was performed based on the number of iStents implanted and the follow-up period. The outcome measures were changes in the IOP and number of glaucoma medications. Results The search strategy identified 105 records from published literature and 9 records from the grey literature. Five studies with 248 subjects were included for quantitative synthesis. A 22% IOP reduction (IOPR%) from baseline occurred at 18-months after one iStent implant, 30% at 6-months after two iStents implantations, and 40% at 6-months after implantation of three iStents. A mean

  9. High coronary calcium score and post-procedural CK-MB are noninvasive predictors of coronary stent restenosis

    PubMed Central

    Lee, Jae-Beom; Choi, Yun-Seok; Chung, Woo-Baek; Kwon, Ami; Park, Chul-Soo; Lee, Man-Young

    2017-01-01

    Purpose High coronary calcium score (CCS) and post-procedural cardiac enzyme may be related with poor outcomes in patients with coronary stent implantation. Methods A total of 1,072 patients (63.2% male, mean age: 61.7±10.3 years) who underwent coronary multi-detect computed tomography at index procedure and follow-up coronary angiography (CAG) after drug-eluting stent (DES) were divided into two groups: those with and without target lesion revascularization (TLR; >50% reduction in luminal stent diameter or angina symptoms on follow-up CAG). The CCSs for predicting stent revascularization were elucidated. Results There were no significant differences between the two groups with regard to risk factors. The initial CCS was significantly higher in the TLR group (1,102.4±743.7 vs 345.8±51.05, P=0.04). After adjustment of significant factors for TLR, only CCS and post-procedural creatine kinase MB form (CK-MB) elevation were significant predictors of coronary artery TLR. Receiver operation curve revealed that >800 in CCS had 69% in sensitivity and 88% in specificity about predicting the TLR. Conclusion High CCS with post-procedural CK-MB might be the useful predictors for TLR after DES implantation. PMID:28255235

  10. Computational replication of the patient-specific stenting procedure for coronary artery bifurcations: From OCT and CT imaging to structural and hemodynamics analyses.

    PubMed

    Chiastra, Claudio; Wu, Wei; Dickerhoff, Benjamin; Aleiou, Ali; Dubini, Gabriele; Otake, Hiromasa; Migliavacca, Francesco; LaDisa, John F

    2016-07-26

    The optimal stenting technique for coronary artery bifurcations is still debated. With additional advances computational simulations can soon be used to compare stent designs or strategies based on verified structural and hemodynamics results in order to identify the optimal solution for each individual's anatomy. In this study, patient-specific simulations of stent deployment were performed for 2 cases to replicate the complete procedure conducted by interventional cardiologists. Subsequent computational fluid dynamics (CFD) analyses were conducted to quantify hemodynamic quantities linked to restenosis. Patient-specific pre-operative models of coronary bifurcations were reconstructed from CT angiography and optical coherence tomography (OCT). Plaque location and composition were estimated from OCT and assigned to models, and structural simulations were performed in Abaqus. Artery geometries after virtual stent expansion of Xience Prime or Nobori stents created in SolidWorks were compared to post-operative geometry from OCT and CT before being extracted and used for CFD simulations in SimVascular. Inflow boundary conditions based on body surface area, and downstream vascular resistances and capacitances were applied at branches to mimic physiology. Artery geometries obtained after virtual expansion were in good agreement with those reconstructed from patient images. Quantitative comparison of the distance between reconstructed and post-stent geometries revealed a maximum difference in area of 20.4%. Adverse indices of wall shear stress were more pronounced for thicker Nobori stents in both patients. These findings verify structural analyses of stent expansion, introduce a workflow to combine software packages for solid and fluid mechanics analysis, and underscore important stent design features from prior idealized studies. The proposed approach may ultimately be useful in determining an optimal choice of stent and position for each patient.

  11. Experimental Comparison of the Hemodynamic Effects of Bifurcating Coronary Stent Implantation Techniques

    NASA Astrophysics Data System (ADS)

    Brindise, Melissa; Vlachos, Pavlos; AETheR Lab Team

    2015-11-01

    Stent implantation in coronary bifurcations imposes unique effects to the blood flow patterns and currently there is no universally accepted stent deployment approach. Despite the fact that stent-induced changes can greatly alter clinical outcomes, no concrete understanding exists regarding the hemodynamic effects of each implantation method. This work presents an experimental evaluation of the hemodynamic differences between implantation techniques. We used four common stent implantation methods including the currently preferred one-stent provisional side branch (PSB) technique and the crush (CRU), Culotte (CUL), and T-stenting (T-PR) two-stent techniques, all deployed by a cardiologist in coronary models. Particle image velocimetry was used to obtain velocity and pressure fields. Wall shear stress (WSS), oscillatory shear index, residence times, and drag and compliance metrics were evaluated and compared against an un-stented case. The results of this study demonstrate that while PSB is preferred, both it and T-PR yielded detrimental hemodynamic effects such as low WSS values. CRU provided polarizing and unbalanced results. CUL demonstrated a symmetric flow field, balanced WSS distribution, and ultimately the most favorable hemodynamic environment.

  12. Hybrid procedure for celiac trunk aneurysm repair via left reno-splenic bypass and stent-graft deployment.

    PubMed

    Gabrielli, Roberto; Rosati, Maria Sofia; Siani, Andrea; Chiappa, Roberto; Caselli, Giovanni

    2012-01-01

    Celiac trunk aneurysm is one of the rarest forms of splanchnic artery aneurysm. Conventional open vascular surgery is associated with increased rates of morbidity and mortality and can require complex vascular reconstruction.We describe the case of a 42-year-old patient with celiac trunk aneurysm whom we treated by means of a hybrid surgical-endovascular procedure. We performed a left reno-splenic bypass, after which we used a direct splenic artery approach to deploy a self-expandable 6 × 50-mm stent-graft across the splenic and hepatic arteries. One year later, the stability of the repair was confirmed.

  13. Hybrid Procedure for Celiac Trunk Aneurysm Repair via Left Reno-Splenic Bypass and Stent-Graft Deployment

    PubMed Central

    Gabrielli, Roberto; Rosati, Maria Sofia; Siani, Andrea; Chiappa, Roberto; Caselli, Giovanni

    2012-01-01

    Celiac trunk aneurysm is one of the rarest forms of splanchnic artery aneurysm. Conventional open vascular surgery is associated with increased rates of morbidity and mortality and can require complex vascular reconstruction. We describe the case of a 42-year-old patient with celiac trunk aneurysm whom we treated by means of a hybrid surgical-endovascular procedure. We performed a left reno-splenic bypass, after which we used a direct splenic artery approach to deploy a self-expandable 6 × 50-mm stent-graft across the splenic and hepatic arteries. One year later, the stability of the repair was confirmed. PMID:22719156

  14. Heterogeneous Intravascular Ultrasound Findings of Stent Thrombosis

    PubMed Central

    Morofuji, Toru; Inaba, Shinji; Aisu, Hiroe; Takahashi, Kayo; Saito, Makoto; Higashi, Haruhiko; Yoshii, Toyofumi; Sumimoto, Takumi

    2017-01-01

    Objective The underlying mechanisms of stent thrombosis are not completely understood. Methods We experienced 12 definite stent thrombosis cases (1 early, 1 late, and 10 very late) at our hospital from July 2011 to April 2016 and evaluated the possible causes of stent thrombosis by intravascular ultrasound (IVUS). Results Five different potential morphological causes of stent thrombosis (neoatherosclerosis, stent malapposition, stent fracture, edge dissection, and stent underexpansion) were detected by IVUS in 10 cases (83.3%); in 1 of the remaining 2 cases, the discontinuation of antithrombotic drugs resulted in early stent thrombosis without abnormal IVUS findings. Of the 12 stent thrombosis cases, 4 occurred at a bare-metal stent (average time from stent implantation, 106 months); in all 12, significant neointimal hyperplasia was observed on IVUS, and 2 had plaque ruptures at an in-stent or proximal reference. Malapposed stent struts were observed in three very-late stent thromboses, and all of these underwent sirolimus-eluting stent implantation. Stent thrombosis due to mechanical (stent fracture) or procedure-related complications (edge dissection and stent underexpansion) was observed in three cases. Conclusion In patients with stent thrombosis, heterogeneous findings were observed in IVUS. This IVUS case series illustrates the possible mechanisms of stent thrombosis. PMID:28154268

  15. A Report of Successful Procedural, Clinical, and Angiographic Outcomes with a Tapered Stent of a Patient in Naturally Tapered Coronary Vessel

    PubMed Central

    Kumar, Yerra Shiv

    2017-01-01

    In cases involving stenosis or occlusions in major parts of a long vessel, natural tapering of coronary vessels may create dilemma in deciding the optimal stent size during percutaneous coronary intervention. In this regard, tapered stents have been developed recently. Herein, we present a case of 67-year-old male patient with triple vessel disease including two tandem lesions in naturally tapered Left Anterior Descending (LAD) artery. The patient received a 3.0–2.5x60 mm Sirolimus-eluting BioMime Morph stent (Meril life Sciences, Gujarat, India) in the mid-distal LAD lesion along with conventional stent implantations in other two lesions. The procedure was successful and good coronary flow was obtained after revascularization. The patient remained asymptomatic thereafter. At one year, angiographic follow-up revealed good flow and no restenosis in the LAD vessel. We are of opinion that using tapered stents with decremented diameter may offer the advantages of excellent adaptation to vessel size, vessel tapering, and good apposition in patients with long coronary lesions in tapered vessels. PMID:28273994

  16. Update in urethral stents.

    PubMed

    Bahouth, Z; Meyer, G; Yildiz, G; Nativ, O; Moskovitz, B

    2016-10-01

    Urethral stents were first introduced in 1988, and since then, they have undergone significant improvements. However, they did not gain a wide popularity and their use is limited to a small number of centers around the world. Urethral stents can be used in the entire urethra and for various and diverse indications. In the anterior urethra, it can be used to treat urethral strictures. In the prostatic urethra, they can be used for the treatment of prostatic obstruction, including benign, malignant and iatrogenic prostatic obstruction. Moreover, although not widely used, it can be also applied for the treatment of posterior urethral stricture and bladder neck contracture, usually resulting in urinary incontinence and the need for subsequent procedures. Our main experience are with Allium urethral stents, and as such, we provide the latest updates in urethral stents with special emphasis on the various types of Allium urethral stents: bulbar, prostatic and bladder neck stents.

  17. Gastrointestinal Stent Update

    PubMed Central

    2010-01-01

    The use of self-expanding metallic stents in the upper gastrointestinal tract, placed under radiologic imaging or endoscopic guidance, is the current treatment of choice for the palliation of malignant gastrointestinal outlet obstructions. Advances in metallic stent design and delivery systems have progressed to the stage where this treatment is now considered a minimally invasive therapy. Metallic stent placement will broaden further into the field of nonsurgical therapy for the gastrointestinal tract. To date, metallic stents placed in the esophagus, gastric outlet, colorectum, and bile ducts are not intended to be curative, but rather to provide a palliative treatment for obstructions. The evolution of metallic stent technology will render such procedures not only palliative but also therapeutic, by enabling local drug delivery, and the use of biodegradable materials will reduce procedure-related complications. PMID:21103290

  18. Future developments in biliary stenting

    PubMed Central

    Hair, Clark D; Sejpal, Divyesh V

    2013-01-01

    Biliary stenting has evolved dramatically over the past 30 years. Advancements in stent design have led to prolonged patency and improved efficacy. However, biliary stenting is still affected by occlusion, migration, anatomical difficulties, and the need for repeat procedures. Multiple novel plastic biliary stent designs have recently been introduced with the primary goals of reduced migration and improved ease of placement. Self-expandable bioabsorbable stents are currently being investigated in animal models. Although not US Food and Drug Administration approved for benign disease, fully covered self-expandable metal stents are increasingly being used in a variety of benign biliary conditions. In malignant disease, developments are being made to improve ease of placement and stent patency for both hilar and distal biliary strictures. The purpose of this review is to describe recent developments and future directions of biliary stenting. PMID:23837001

  19. The "Lantern" Procedure to Simplify Treatment of Retrograde Type A Dissection After Thoracic Endograft Stenting.

    PubMed

    Tsai, Chung-Lin

    2016-04-01

    The emergency repair of retrograde type A aortic dissection after thoracic endovascular aortic repair is a complex and challenging surgical procedure and carries a surgical challenge. Previous studies have reported a significant mortality in the complex repair of retrograde type A aortic dissection after thoracic endovascular aortic repair. We devised a simplified hybrid method-the "Lantern" procedure-to solve this retrograde type A aortic dissection complication.

  20. Percutaneous valved stent repair of a failed homograft: implications for the Ross procedure.

    PubMed

    Pretorius, Victor; Jones, Alan; Taylor, Dylan; Coe, Yashu; Ross, David B

    2008-08-01

    A case of percutaneous pulmonary valve implantation following a failed homograft in the pulmonary position is reported. A 16-year-old boy developed infective endocarditis of his pulmonary homograft, which was implanted four years earlier during a Ross procedure for congenital aortic stenosis. Following successful medical therapy, the boy was symptomatic due to pulmonary stenosis and regurgitation. A 22 mm Melody valve (Medtronic, USA) was successfully implanted percutaneously. His symptoms resolved and he was discharged home one day after the procedure. Echocardiography at the six-month follow-up demonstrated a normally functioning pulmonary valve. Percutaneous pulmonary valve replacement may make the Ross procedure a more attractive option for patients with aortic stenosis, particularly in the pediatric population.

  1. Overlap stenting for in-stent restenosis after carotid artery stenting

    PubMed Central

    Nishihori, Masahiro; Ohshima, Tomotaka; Yamamoto, Taiki; Goto, Shunsaku; Nishizawa, Toshihisa; Shimato, Shinji; Izumi, Takashi; Kato, Kyozo

    2016-01-01

    ABSTRACT Our aim was to assess the clinical safety and efficacy of overlap stenting for in-stent restenosis after carotid artery stenting. The study was conducted between July 2008 and February 2015. A database of consecutive carotid artery stenting procedures was retrospectively assessed to identify the cases of in-stent restenosis that were treated with overlap stenting under proximal or distal protection. The clinical and radiological records of the patients were then reviewed. Of the 155 CAS procedures in 149 patients from the database, 6 patients met the inclusion criteria. All the 6 patients were initially treated with moderate dilatation because of the presence of an unstable plaque. The technical success rate of the overlap stenting was 100%, with no 30-day mortality or morbidity. In addition, there was no further in-stent restenosis during a follow-up period of over 12 months. These results indicated that overlap stenting for in-stent restenosis after carotid artery stenting was both safe and effective in our cohort. PMID:27303101

  2. Stent Graft in Managing Juxta-Renal Aortoiliac Occlusion

    SciTech Connect

    Prabhudesai, V. Mitra, K.; West, D. J.; Dean, M. R. E.

    2003-09-15

    Endovascular procedures are frequently used as an alternative to surgical bypass in aortic and iliac occlusion. Stents have revolutionized the scope of such endovascular procedures, but there are few reports of stents or stent grafts in occlusive juxta-renal aortic occlusion. We present a case where such occlusion was managed by use of a stent graft with successful outcome.

  3. [Stent Grafting for Aortic Dissection].

    PubMed

    Uchida, Naomichi

    2016-07-01

    The purpose of stent graft for aortic dissection is to terminate antegrade blood flow into the false lumen through primary entry. Early intervention for primary entry makes excellent aortic remodeling and emergent stent grafting for complicated acute type B aortic dissection is supported as a class I. On the other hand stent grafting for chronic aortic dissection is controversial. Early stent grafting is considered with in 6 months after on-set if the diameter of the descending aorta is more than 40 mm. Additional interventions for residual false lumen on the downstream aorta are still required. Stent graft for re-entry, candy-plug technique, and double stenting, other effective re-interventions were reported. Best treatment on the basis of each anatomical and physical characteristics should be selected in each institution. Frozen elephant trunk is alternative procedure for aortic dissection without the need to take account of proximal anatomical limitation and effective for acute type A aortic dissection.

  4. iStent® Trabecular Microbypass Stent: An Update

    PubMed Central

    Resende, Arthur Fernandes; Patel, Neal Sanjay; Waisbourd, Michael; Katz, L. Jay

    2016-01-01

    Due to the high rates of complications and failure experienced with current glaucoma procedures, there is a continuous search for a safer and more effective glaucoma surgery. A new class of procedures termed minimally invasive glaucoma surgeries (MIGS) aim to fill this void by offering an alternative method of IOP reduction associated with markedly reduced complication rates and shorter recovery times. The iStent, a trabecular microbypass stent, is a MIGS device that has quickly gained popularity. The device allows aqueous humor to directly drain from the anterior chamber into Schlemm's canal by bypassing an obstructed trabecular meshwork. This review examines publications about the iStent, focusing on the device's efficacy, safety, and cost when a single iStent or multiple iStents are implanted in combination with cataract surgery or as a solo procedure. Current data suggest that the iStent is a safe and effective tool in the management of mild-to-moderate glaucoma, notable for its limited complications and absence of serious adverse events following implantation. As valuable experience is gained performing ab interno MIGS, increasing familiarity with angle anatomy and iStent placement, and as newer stent designs are developed, there is promise of continual improvement in the surgical management of glaucoma. PMID:27413541

  5. The need for stent-lesion matching to optimize outcomes of intracoronary stent implantation.

    PubMed

    Lanzer, Peter; Strupp, Gerhard; Schmidt, Wolfram; Topoleski, L D Timmie

    2013-11-01

    Intracoronary stents have markedly improved the outcomes of catheter-based coronary interventions. Intracoronary stent implantation rates of over 90% during coronary angioplasty are common. Stent implantations are associated with a small but statistically significant number of adverse outcomes including restenosis, thrombosis, strut malapposition, incomplete strut endothelialization, and various types of stenting failure. Better matching of biomechanical properties of stents and lesions could further improve the clinical outcome of intracoronary stenting. Thus, in this article, we assess the need for advanced intracoronary stent-lesion matching. We reviewed the data on biomechanics of coronary stents and lesions to develop knowledge-based rationale for optimum intracoronary stent selection. The available technical information on marketed intracoronary stents and the current understanding of the biomechanical properties of coronary lesions at rest and under stress are limited, preventing the development of knowledge-based rationale for optimum intracoronary stent selection at present. Development of knowledge-based selection of intracoronary stents requires standardization of mechanical stent testing, communication of the nonproprietary technical data on stents by the industry and dedicated research into procedural stent-lesion interactions.

  6. Renal Artery Stent Outcomes

    PubMed Central

    Murphy, Timothy P.; Cooper, Christopher J.; Matsumoto, Alan H.; Cutlip, Donald E.; Pencina, Karol M.; Jamerson, Kenneth; Tuttle, Katherine R.; Shapiro, Joseph I.; D’Agostino, Ralph; Massaro, Joseph; Henrich, William; Dworkin, Lance D.

    2016-01-01

    BACKGROUND Multiple randomized clinical trials comparing renal artery stent placement plus medical therapy with medical therapy alone have not shown any benefit of stent placement. However, debate continues whether patients with extreme pressure gradients, stenosis severity, or baseline blood pressure benefit from stent revascularization. OBJECTIVES The study sought to test the hypothesis that pressure gradients, stenosis severity, and/or baseline blood pressure affects outcomes after renal artery stent placement. METHODS Using data from 947 patients with a history of hypertension or chronic kidney disease from the largest randomized trial of renal artery stent placement, the CORAL (Cardiovascular Outcomes in Renal Atherosclerotic Lesions) study, we performed exploratory analyses to determine if subsets of patients experienced better outcomes after stent placement than the overall cohort. We examined baseline stenosis severity, systolic blood pressure, and translesion pressure gradient (peak systolic and mean) and performed interaction tests and Cox proportional hazards analyses for the occurrence of the primary endpoint through all follow-up, to examine the effect of these variables on outcomes by treatment group. RESULTS There were no statistically significant differences in outcomes based on the examined variables nor were there any consistent nonsignificant trends. CONCLUSIONS Based on data from the CORAL randomized trial, there is no evidence of a significant treatment effect of the renal artery stent procedure compared with medical therapy alone based on stenosis severity, level of systolic blood pressure elevation, or according to the magnitude of the transstenotic pressure gradient. (Benefits of Medical Therapy Plus Stenting for Renal Atherosclerotic Lesions [CORAL]; NCT00081731) PMID:26653621

  7. Safety, efficacy and costs associated with direct coronary stenting compared with stenting after predilatation

    PubMed Central

    IJsselmuiden, A.; Serruys, P.W.; Tangelder, G.J.; Slagboom, T.; van der Wieken, R.; Kiemeneij, F.; Laarman, G.J.

    2004-01-01

    Objectives Comparison of the in-hospital success rates, procedural costs and short-term clinical outcomes of direct stenting versus stenting after balloon predilatation. Methods Altogether, 400 patients with angina pectoris and/or myocardial ischaemia due to coronary stenoses in a single native vessel were randomised to either direct stenting or stenting after predilatation. Baseline characteristics were evenly distributed between the two groups. Results Procedural success rates were similar (96.0% direct stenting group vs. 94.5% predilatation) as well as final successful stent implantation (98.3 vs. 97.8%), while the primary success rate of direct stenting alone was 88.3%, p=0.01. In multivariate analysis, angiographic lesion calcification was an independent predictor of unsuccessful direct stenting (odds ratio 7.1, 95% confidence interval 2.8-18.2, p<0.0001). Rates of troponin I rises >0.15 μg/l, used as a measure of distal embolisation, were similar in both groups (17.8 vs. 17.1%). Rates of major adverse cardiac events at 30 days were 4.5% in the direct stenting group versus 5.5% in the predilated group (ns). Direct stenting was associated with savings in fluoroscopy time, and angiographic contrast agent use, and a reduction in utilisation of angioplasty balloons (0.4 vs. 1.17 balloons per patient, p<0.001). Mean per patient procedural costs associated with direct stenting versus predilatation were €2545±914 versus €2763±842 (p=0.01), despite the implantation of more stents in the directly stented group. Conclusion Compared with a strategy of stenting preceded by balloon predilatation, direct stenting was equally safe and effective, with similar in-hospital and 30-day clinical outcomes, and modest procedural cost-savings. A calcified lesion predicted unsuccessful direct stenting. PMID:25696356

  8. Safety and Efficacy of Two Trabecular Micro-Bypass Stents as the Sole Procedure in Japanese Patients with Medically Uncontrolled Primary Open-Angle Glaucoma: A Pilot Case Series

    PubMed Central

    Hosoda, Shingo; Yaguchi, Saori

    2017-01-01

    Purpose. To evaluate efficacy and safety of a trabecular micro-bypass stent system when used as the sole procedure in Japanese patients with medically uncontrolled primary open-angle glaucoma (POAG). Design. Prospective nonrandomized interventional pilot study. Methods. Ten eyes of 10 Japanese patients with medically uncontrolled POAG taking three ocular hypotensive medications were treated using only the implantation of two iStent trabecular micro-bypass stents. Each patient continued to take the same ocular hypotensive medications used preoperatively throughout the study. Intraocular pressure (IOP) and endothelial cell density (ECD) were determined at baseline and at 1, 3, and 6 months postoperatively. Best-corrected visual acuity (BCVA) was measured at baseline and 6 months after surgery. Results. Mean IOP was 22.0 ± 3.0 mmHg at baseline and 16.9 ± 3.6 mmHg at 6 months, which represented a mean reduction of 5.1 mmHg or 23.2%. No significant changes were observed in the ECD and BCVA. Complications that occurred during the early postoperative period included hyphema, peripheral anterior synechiae, and occlusion of the stent by the iris. Conclusion. Implantation of two trabecular micro-bypass stents as the sole procedure in Japanese POAG patients effectively reduced IOP and exhibited a favorable safety profile. Clinical Trials Registration number is UMIN000004002. PMID:28265466

  9. Stent graft implantation in an aortic pseudoaneurysm associated with a fractured Cheatham-Platinum stent in aortic coarctation.

    PubMed

    Kuhelj, Dimitrij; Berden, Pavel; Podnar, Tomaž

    2016-03-01

    We report a case of aortic pseudoaneurysm associated with a fractured bare Cheatham-Platinum stent following stenting for aortic coarctation. These complications were recognised 6 years after the implantation procedure and were successfully managed by percutaneous stent graft implantation. Staged approach for stent dilatation might prevent development of aortic pseudoaneurysms. In addition, careful follow-up is warranted after stenting for aortic coarctation, particularly in patients with recognised aortic wall injury.

  10. Carotid artery stenting: which stent for which lesion?

    PubMed

    Bosiers, Marc; Deloose, Koen; Verbist, Jürgen; Peeters, Patrick

    2005-01-01

    The different geometries and working principles of carotid stents (nitinol or cobalt chromium, open- or closed-cell configuration) provide each product with unique functional properties. The individual characteristics of each device may make it an attractive choice in one circumstance but render it less desirable in other situations. In approximately 75% of all procedures, all types of stents will achieve similar outcomes, making adequate device selection unnecessary. For the remaining quarter, careful preoperative screening is mandatory. In addition to eventual access issues, the choice of the optimal carotid stent depends mainly on arterial anatomy and lesion morphology. When treating a tortuous anatomy, stents with a flexible and comformable open-cell configuration are preferred. In arteries with a significant mismatch between common carotid artery and internal carotid artery diameter, cobalt chromium (Elgiloy) or tapered nitinol stents are selected. Lesions with suspected high emboligenicity are best covered with stents with a closed-cell configuration, whereas highly calcified lesions need treatment with nitinol stents. Thorough knowledge of the characteristics, advantages and disadvantages, and working principles of the different available stents is mandatory to optimally select the materials to be used for patients eligible for carotid revascularization.

  11. A new removable airway stent

    PubMed Central

    Amundsen, Tore; Sørhaug, Sveinung; Leira, Håkon Olav; Tyvold, Stig Sverre; Langø, Thomas; Hammer, Tommy; Manstad-Hulaas, Frode; Mattsson, Erney

    2016-01-01

    Background Malignant airway obstruction is a feared complication and will most probably occur more frequently in the future because of increasing cancer incidence and increased life expectancy in cancer patients. Minimal invasive treatment using airway stents represents a meaningful and life-saving palliation. We present a new removable airway stent for improved individualised treatment. Methods To our knowledge, the new airway stent is the world's first knitted and uncovered self-expanding metal stent, which can unravel and be completely removed. In an in vivo model using two anaesthetised and spontaneously breathing pigs, we deployed and subsequently removed the stents by unravelling the device. The procedures were executed by flexible bronchoscopy in an acute and a chronic setting – a ‘proof-of-principle’ study. Results The new stent was easily and accurately deployed in the central airways, and it remained fixed in its original position. It was easy to unravel and completely remove from the airways without clinically significant complications. During the presence of the stent in the chronic study, granulation tissue was induced. This tissue disappeared spontaneously with the removal. Conclusions The new removable stent functioned according to its purpose and unravelled easily, and it was completely removed without significant technical or medical complications. Induced granulation tissue disappeared spontaneously. Further studies on animals and humans are needed to define its optimal indications and future use. PMID:27608269

  12. [Absorbable coronary stents. New promising technology].

    PubMed

    Erbel, Raimund; Böse, Dirk; Haude, Michael; Kordish, Igor; Churzidze, Sofia; Malyar, Nasser; Konorza, Thomas; Sack, Stefan

    2007-06-01

    Coronary stent implantation started in Germany 20 years ago. In the beginning, the progress was very slow and accelerated 10 years later. Meanwhile, coronary stent implantation is a standard procedure in interventional cardiology. From the beginning of permanent stent implantation, research started to provide temporary stenting of coronary arteries, first with catheter-based systems, later with stent-alone technology. Stents were produced from polymers or metal. The first polymer stent implantation failed except the Igaki-Tamai stent in Japan. Newly developed absorbable polymer stents seem to be very promising, as intravascular ultrasound (IVUS) and optical coherence tomography have demonstrated. Temporary metal stents were developed based on iron and magnesium. Currently, the iron stent is tested in peripheral arteries. The absorbable magnesium stent (Biotronik, Berlin, Germany) was tested in peripheral arteries below the knee and meanwhile in the multicenter international PROGRESS-AMS (Clinical Performance and Angiographic Results of Coronary Stenting with Absorbable Metal Stents) study. The first magnesium stent implantation was performed on July 30, 2004 after extended experimental testing in Essen. The magnesium stent behaved like a bare-metal stent with low recoil of 5-7%. The stent struts were absorbed when tested with IVUS. Stent struts were not visible by fluoroscopy or computed tomography (CT) as well as magnetic resonance imaging (MRI). That means, that the magnesium stent is invisible and therefore CT and MRI can be used for imaging of interventions. Only using micro-CT the stent struts were visible. The absorption process could be demonstrated in a patient 18 days after implantation due to suspected acute coronary syndrome, which was excluded. IVUS showed a nice open lumen. Stent struts were no longer visible, but replaced by tissue indicating the previous stent location. Coronary angiography after 4 months showed an ischemia-driven target lesion

  13. Post-sialendoscopy ductoplasty by salivary duct stent placements.

    PubMed

    Su, Chin-Hui; Lee, Kuo-Sheng; Tseng, Te-Ming; Hung, Shih-Han

    2016-01-01

    With damage to a duct or papilla after sialendoscopy, a stent may be necessary to prevent re-stenosis and for maintaining the salivary duct open after complete sialendoscopy. However factors affecting outcomes and complications after stent placement remain unclear. This study aimed to report preliminary experiences in salivary duct stent placement after sialendoscopy. Data from 35 procedures in 33 patients who received sialendoscopy with salivary duct stent placements at Mackay Memorial Hospital between October 2013 and June 2014 were recorded and compared for clinical data, as well as procedural techniques, findings, and outcomes. In the 35 stent placement procedures, the hypospadias silastic stent tubes were used in 27 and the Fr. 5 pediatric feeding tubes were used in the remaining eight. When the hypospadias silastic stent tubes were used for stenting, the stent obstruction and irritation rates were higher compared to those who used the Fr. 5 pediatric feeding tube (100 vs. 0 % and 67 vs. 33 %, respectively). None of the stents secured by a 5-0 nylon suture were complicated by dislocation but when the stents were secured by 6-0 nylon sutures, the dislocation rate went as high as 47.4 %. The duration needed for salivary duct stent placement might be potentially shortened to only 2 weeks. If a salivary duct stent is intended to be placed for a certain period before its scheduled removal, a suture strength equivalent or stronger than the 5-0 nylon suture should be considered for stent fixation.

  14. Therapeutic efficacy and stent patency of transhepatic portal vein stenting after surgery

    PubMed Central

    Jeon, Ung Bae; Kim, Chang Won; Kim, Tae Un; Choo, Ki Seok; Jang, Joo Yeon; Nam, Kyung Jin; Chu, Chong Woo; Ryu, Je Ho

    2016-01-01

    AIM To evaluate portal vein (PV) stenosis and stent patency after hepatobiliary and pancreatic surgery, using abdominal computed tomography (CT). METHODS Percutaneous portal venous stenting was attempted in 22 patients with significant PV stenosis (> 50%) - after hepatobiliary or pancreatic surgery - diagnosed by abdominal CT. Stents were placed in various stenotic lesions after percutaneous transhepatic portography. Pressure gradient across the stenotic segment was measured in 14 patients. Stents were placed when the pressure gradient across the stenotic segment was > 5 mmHg or PV stenosis was > 50%, as observed on transhepatic portography. Patients underwent follow-up abdominal CT and technical and clinical success, complications, and stent patency were evaluated. RESULTS Stent placement was successful in 21 patients (technical success rate: 95.5%). Stents were positioned through the main PV and superior mesenteric vein (n = 13), main PV (n = 2), right and main PV (n = 1), left and main PV (n = 4), or main PV and splenic vein (n = 1). Patients showed no complications after stent placement. The time between procedure and final follow-up CT was 41-761 d (mean: 374.5 d). Twenty stents remained patent during the entire follow-up. Stent obstruction - caused by invasion of the PV stent by a recurrent tumor - was observed in 1 patient in a follow-up CT performed after 155 d after the procedure. The cumulative stent patency rate was 95.7%. Small in-stent low-density areas were found in 11 (55%) patients; however, during successive follow-up CT, the extent of these areas had decreased. CONCLUSION Percutaneous transhepatic stent placement can be safe and effective in cases of PV stenosis after hepatobiliary and pancreatic surgery. Stents show excellent patency in follow-up abdominal CT, despite development of small in-stent low-density areas. PMID:27956806

  15. Novel side branch ostial stent.

    PubMed

    Chen, Shao-Liang; Lv, Shu-Zheng; Kwan, Tak W

    2009-04-01

    Bifurcation lesions are technically challenging and plagued by a high incidence of restenosis, especially at the side branch orifice, which results in a more frequent need for revascularization during the follow-up period. This report discusses two clinical experiences with a novel side branch ostial stent, the BIGUARD stent, designed for the treatment of bifurcation lesions; procedural success with no in-hospital complications was observed in types IVb and Ia lesions.

  16. Predictive Factors of In-Stent Restenosis in Renal Artery Stenting: A Retrospective Analysis

    SciTech Connect

    Vignali, Claudio Bargellini, Irene; Lazzereschi, Michele; Cioni, Roberto; Petruzzi, Pasquale; Caramella, Davide; Pinto, Stefania; Napoli, Vinicio; Zampa, Virna; Bartolozzi, Carlo

    2005-04-15

    Purpose. To retrospectively evaluate the role of clinical and procedural factors in predicting in-stent restenosis in patients with renovascular disease treated by renal artery stenting. Methods. From 1995 to 2002, 147 patients underwent renal artery stenting for the treatment of significant ostial atherosclerotic stenosis. Patients underwent strict clinical and color-coded duplex ultrasound follow-up. Ninety-nine patients (111 stents), with over 6 months of continuous follow-up (mean 22{+-}12 months, range 6-60 months), were selected and classified according to the presence (group A, 30 patients, 32 lesions) or absence (group B, 69 patients, 79 lesions) of significant in-stent restenosis. A statistical analysis was performed to identify possible preprocedural and procedural predictors of restenosis considering the following data: sex, age, smoking habit, diabetes mellitus, hypertension, serum creatinine, cholesterol and triglyceride levels, renal artery stenosis grade, and stent type, length and diameter. Results. Comparing group A and B patients ({chi}{sup 2} test), a statistically significant relation was demonstrated between stent diameter and length and restenosis: the risk of in-stent restenosis decreased when the stent was {>=}6 mm in diameter and between 15 and 20 mm in length. This finding was confirmed by multiple logistic regression analysis. Stent diameter and length were proved to be significantly related to in-stent restenosis also when evaluating only patients treated by Palmaz stent (71 stents). Conclusion. Although it is based on a retrospective analysis, the present study confirms the importance of correct stent selection in increasing long-term patency, using stents of at least 6 mm in diameter and with a length of approximately 15-20 mm.

  17. Emerging Stent and Balloon Technologies in the Femoropopliteal Arteries

    PubMed Central

    Pastromas, Georgios; Katsanos, Konstantinos; Krokidis, Miltiadis; Karnabatidis, Dimitrios

    2014-01-01

    Endovascular procedures for the management of the superficial femoral (SFA) and popliteal artery disease are increasingly common. Over the past decade, several stent technologies have been established which may offer new options for improved clinical outcomes. This paper reviews the current evidence for SFA and popliteal artery angioplasty and stenting, with a focus on randomized trials and registries of nitinol self-expanding stents, drug-eluting stents, dug-coated balloons, and covered stent-grafts. We also highlight the limitations of the currently available data and the future routes in peripheral arterial disease (PAD) stent and balloon technology. PMID:24672355

  18. Subintimal Double-Barrel Restenting of an Occluded Primary Stented Superficial Femoral Artery

    PubMed Central

    Lohle, Paul N.M.; Lampmann, Leo E.H.

    2007-01-01

    In-stent re-stenosis is a frequent complication of endovascular stents, especially in the superficial femoral artery (SFA). Endovascular re-intervention of in- or peri-stent occlusive disease consists of recanilization through the occluded stent. In our case report, we describe the endovascular treatment of a previously placed stent in the SFA. We unintentionally passed the affected stent subintimally, in a double barrel fashion next to the first stent. The procedure was without any complications and with a successfull angiographic result. At one year follow-up the patient still has no complaints and the stent is still patent. PMID:17410397

  19. Preprocedural planning for endovascular stent-graft placement.

    PubMed

    Kicska, Gregory; Litt, Harold

    2009-03-01

    Endovascular stent grafts have become a viable treatment for aortic thoracic and abdominal aneurysms in both elective and emergent situations. Computed tomographic (CT) angiography is the primary tool for determining eligibility for this procedure. This article discuses the preprocedural evaluation of an endovascular stent candidate. Evaluation begins with identification of the aneurysm pathology and its relationship to treatment efficacy. The radiologist must evaluate the aneurysm geometry for compatibility with stent hardware. Aneurysm features that suggest a contraindication must be recognized. Procedures that involve a combination of endovascular stenting and surgical revascularization are discussed so that the reader understands the limits of stent eligibility. Vascular access for stent placement must also be evaluated for the ability to accommodate stent delivery. The radiologist also must be familiar with CT imaging protocols and alternative methods of imaging that can evaluate stent feasibility. The utility of three-dimensional processing is discussed.

  20. Review of stents for the carotid artery.

    PubMed

    Bosiers, M; Deloose, K; Verbist, J; Peeters, P

    2006-04-01

    The individual characteristics of a stent may make it an attractive choice in some circumstances, but render it a less desirable option in others. The applicability depends primarily on the arterial anatomy and the specific details of the lesion being treated. A careful assessment by the interventionalist is required to select the proper type of stent that is of appropriate size. Certainly, personal preferences and familiarity with a specific device may legitimately influence the decision to choose one stent over another. Finally, stent design can play a role in the selection procedure. Although carotid stents are often functionally equivalent in the clinical setting and have been used successfully to treat a wide variety of lesions, a basic knowledge of stent geometry can contribute to make up your mind in certain carotid cases.

  1. Treatment of Vertebro-Basilar Dissecting Aneurysms Using Intravascular Stents

    PubMed Central

    Yamasaki, S.; Hashimoto, K.; Kawano, Y.; Yoshimura, M.; Yamamoto, T.; Hara, M.

    2006-01-01

    Summary Endovascular surgery is an established primary therapeutic modality for dissecting aneurysms at vertebro-basilar arteries. Intravascular stents can be used to treat the dissecting aneurysms for which simple obliteration procedures cannot be used. In such cases, stent implantation alone or a combination of stents and coils need to be selected properly by taking into consideration the site and shape of dissections. In this report, three patterns of stent application are described and their method of selection is discussed. PMID:20569619

  2. Stenting of the Upper Gastrointestinal Tract: Current Status

    SciTech Connect

    Katsanos, Konstantinos; Sabharwal, Tarun Adam, Andreas

    2010-08-15

    Minimally invasive image-guided insertion of self-expanding metal stents in the upper gastrointestinal tract is the current treatment of choice for palliation of malignant esophageal or gastroduodenal outlet obstructions. A concise review is presented of contemporary stenting practice of the upper gastrointestinal tract, and the procedures in terms of appropriate patient evaluation, indications, and contraindications for treatment are analyzed, along with available stent designs, procedural steps, clinical outcomes, inadvertent complications, and future technology. Latest developments include biodegradable polymeric stents for benign disease and radioactive or drug-eluting stents for malignant obstructions.

  3. Clinical outcomes of compromised side branch (stent jail) after coronary stenting with the NIR stent.

    PubMed

    Bhargava, B; Waksman, R; Lansky, A J; Kornowski, R; Mehran, R; Leon, M B

    2001-11-01

    Acute side-branch (SB) compromise or occlusion stent jail after native coronary stenting is a matter of concern. Attempts at maintaining SB patency can be a technical challenge. The purpose of this study was to determine the clinical impact of SB compromise or occlusion in patients undergoing stenting of parent vessel lesions. We evaluated in-hospital and long-term clinical outcomes (death, Q-wave myocardial infarction, and repeat revascularization rates at 6 months) in 318 consecutive patients undergoing NIR stent implantation across an SB. Based on independent angiographic analysis, 218 (68.6%) patients had no poststent SB compromise, 85 (26.7%) patients had narrowed SB (> 70% narrowing, without total occlusion), and 15 (4.7%) patients had an occluded SB after stent implantation. The baseline patient and lesion characteristics were similar between the groups. Procedural success was 100%. Patients with SB occlusion had a higher stents/lesion ratio (P < 0.006). Side-branch occlusion was associated with higher in-hospital ischemic complications (Q-wave myocardial infarction, 7%; non-Q-wave myocardial infarction, 20%; P < 0.05) compared to patients with SB compromise or normal SB. At 6-month follow-up, there was a trend for more myocardial infarctions in the group with SB occlusion during the index procedure (Q-wave myocardial infarction, 7% vs. 1% in the narrowed and 0% in normal SB; P = 0.09). However, late target lesion revascularization and mortality were similar in the three groups (P = 0.91). SB occlusion after parent vessel stenting is associated with more frequent in-hospital Q-wave and non-Q-wave myocardial infarctions. However, with the NIR stent, side-branch compromise or occlusion does not influence late (6 month) major adverse events, including death, myocardial infarction, or need for repeat revascularization.

  4. Spontaneous Subcapsular Renal Hematoma: Strange Case in an Anticoagulated Patient with HWMH after Aortic and Iliac Endovascular Stenting Procedure

    PubMed Central

    Greco, Michele; Benedetto, Filippo; Spinelli, Francesco; Traxer, Olivier; Tefik, Tzevat; Pappalardo, Rosa

    2016-01-01

    Spontaneous subcapsular renal hematoma is a rare condition in clinical practice. It is caused by renal cysts, benign and malignant renal tumors, vascular lesions, and antiplatelet or anticoagulant therapy. In this paper we report an unusual case of rupture of a renal cyst of a 66-year-old male patient during an aortic and iliac endovascular procedure for a massive calcified atheroma above the iliac bifurcation. We suspected that the bolus of high weight molecular heparin given during the procedure caused the rupture of the cyst. According to the literature, this is the first case of renal cyst rupture during an endovascular aortic procedure after administering a high weight molecular heparin bolus. PMID:27579210

  5. A review of the iStent® trabecular micro-bypass stent: safety and efficacy

    PubMed Central

    Wellik, Sarah R; Dale, Elizabeth A

    2015-01-01

    There is a significant demand for procedures that can effectively treat glaucoma with low risk and good visual outcomes. To fill this void, procedures termed “minimally invasive glaucoma surgery”, are gaining in popularity. This review will focus on the safety and efficacy of one such minimally invasive glaucoma surgery procedure, the trabecular micro-bypass stent. This stent is intended to lower intraocular pressure by directly cannulating Schlemm’s canal and thereby enhancing aqueous outflow. Recent randomized controlled trials and case series have demonstrated the micro-bypass stent to be a relatively safe procedure, with limited complications and no serious adverse sequelae. The most common complication across all studies was stent obstruction or malposition, which generally did not result in any adverse outcome in vision or pressure control. In addition, increased rates of hypotony, choroidal hemorrhage, or infection were not seen with the micro-bypass stent in comparison to cataract surgery alone. PMID:25931808

  6. Drug-eluting versus bare-metal coronary stents: where are we now?

    PubMed

    Amoroso, Nicholas S; Bangalore, Sripal

    2012-11-01

    Drug-eluting stents have dramatically reduced the risk of restenosis, but concerns of an increased risk of stent thrombosis have provided uncertainty about their use. Recent studies have continued to show improved procedural and clinical outcomes with drug-eluting stents both in the setting of acute coronary syndromes and stable coronary artery disease. Newer generation drug-eluting stents (especially everolimus-eluting stents) have been shown to be not only efficacious but also safe with reduced risk of stent thrombosis when compared with bare-metal stents, potentially changing the benchmark for stent safety from bare-metal stents to everolimus-eluting stents. While much progress is being made in the development of bioabsorbable polymer stents, nonpolymer stents and bioabsorbable stent technology, it remains to be seen whether these stents will have superior safety and efficacy outcomes compared with the already much improved rates of revascularization and stent thrombosis seen with newer generation stents (everolimus-eluting stents and resolute zotarolimus-eluting stents).

  7. Angioplasty and Vascular Stenting

    MedlinePlus

    ... Drug-coated (also called drug-eluting) stents have recently been approved for clinical use by the U.S. ... you notify the MRI department that you have recently had a stent. Although stents used today may ...

  8. Percutaneous Stent-Graft Repair of Anastomotic Pseudoaneurysms following Vascular Bypass Procedures: A Report of Two Cases

    PubMed Central

    Rundback, John; Haug, James; Herman, Kevin; Manno, Joseph; Cerda, Martin

    2013-01-01

    Anastomotic pseudoaneurysms are common entities following vascular bypass procedures and, if left untreated, serious complications such as thromboses, infection, and rupture can frequently occur. Therefore, attempts to employ various methods of repair have been utilized in treating anastomotic pseudoaneurysms to maximize operational success and future risk reduction. Herein, the authors report two cases of anastomotic pseudoaneurysms which were repaired percutaneously utilizing a combination of strategies such as careful preoperational image planning, multiple commercially available devices, and secondary embolization techniques. PMID:23365781

  9. Nitinol Esophageal Stents: New Designs and Clinical Indications

    SciTech Connect

    Strecker, Ernst-Peter; Boos, Irene; Vetter, Sylvia; Strohm, Michael; Domschke, Sigurd

    1996-11-15

    Purpose: To evaluate the clinical use of covered and noncovered, knitted nitinol stents in patients presenting new stent indications. Methods: Self-expandable, knitted nitinol stents were implanted in four patients for treatment of dysphagia. In two patients who had malignant strictures and had esophago-respiratory fistulae and in one patient with an esophagocutaneous fistula, polytetrafluoroethylene (PTFE)-covered stents were implanted. One patient received a noncovered stent, but a retrograde approach through a percutaneous endoscopic gastrostomy (PEG) fistula had to be chosen for recanalization of an esophageal occlusion. Two patients received stents for treatment of benign strictures. Results: Recanalization of the stricture and stent implantation were performed under fluoroscopic control without any procedure-related morbidity or mortality. Dysphagia improved in all patients and the esophageal fistulae could be sealed off by covered stents. During a maximum follow-up of 18 months, there was no stent migration or esophageal perforation. Complications observed were stent stenosis due to food impaction (1/4) and benign stent stenosis (2/2). Most complications could be treated by the interventional radiologist. Conclusion: Self-expandable, covered Nitinol stents provide an option for the treatment of dysphagia combined with esophageal fistulae. In combination with interventional radiology techniques, even complex strictures are accessible. For benign strictures, the value of stent treatment has not yet been proven.

  10. Long-term follow-up of stent implantation versus stent-like angioplasty in unstable angina.

    PubMed

    Marzocchi, A; Ortolani, P; Piovaccari, G; Marrozzini, C; Palmerini, T; Marinucci, L; Saia, F; Bacchi-Reggiani, M L; Branzi, A; Magnani, B

    1999-03-01

    Stent-like plain old balloon angioplasty (POBA, < or = 30% residual diameter stenosis) in patients with stable angina resulted in a clinical and angiographic long-term outcome equivalent to stenting. In unstable angina POBA showed lower acute and long-term efficacy than in the stable setting. Data comparing stent-like POBA and coronary stenting in unstable angina are lacking in the literature. The aim of this retrospective single-center study was to compare the long-term effectiveness of stent-like POBA and coronary stenting in unstable angina. From January 1996 to December 1996 we retrospectively examined 187 consecutive patients with unstable angina who underwent coronary angioplasty on a native vessel: 135 had coronary stenting in addition to POBA and 50 achieved a stent-like result with POBA. Two patients, with major contraindication to coronary stenting, who did not reach a stent-like angiographic result, were also treated with only POBA but were excluded from the study. Stent implantation indications were: elective (54 stents, 30%), suboptimal angiographic result (104 stents, 58%), and bail-out situation (21 stents, 12%). Stent implantation showed high angiographic (98.5%) and clinical (95.5%) success. Stent thrombosis occurred only in 2 patients (1.5%). At quantitative coronary angiography the stent group showed a higher post-procedure minimal lumen diameter (2.74 +/- 1.25 vs 2.27 +/- 0.58 mm, p = 0.025), acute gain (1.95 +/- 1.28 vs 1.43 +/- 0.57 mm, p = 0.007) and lower residual stenosis diameter (13.89 +/- 7.43 vs 20.4 +/- 7.28%, p = 0.001) than the stent-like POBA group. At 1-year follow-up the stent group showed a higher event-free survival rate (77.9 vs 64.6%, p = 0.009) mainly due to lower recurrence of angina and repetition of percutaneous procedures. Stent-like POBA procedure and baseline lesion length > or = 10 mm proved to be the only independent predictors of long-term ischemic event occurrence. In conclusion, in unstable angina, stent

  11. Gastroesophageal stenting for the management of post sleeve gastrectomy leak

    PubMed Central

    Guzaiz, Noha; Arabi, Mohammad; Khankan, Azzam; Salman, Refaat; Al-Toki, Mohammed; Qazi, Shahbaz; Alzakari, Abdulmohsin; Al-Moaiqel, Mohammad

    2016-01-01

    Objectives To retrospectively evaluate the effectiveness of gastroesophageal stenting for post sleeve gastrectomy staple line leaks using removable self-expandable stents. Methods Between April 2012 and June 2015, 12 consecutive patients (6 males) with mean age of 34 years: (21-38 years) presented with staple line leak 1-8 weeks after the operation (mean 2.8 weeks). Patients underwent gastroesophageal stenting by interventional radiology. A total of 23 stents were deployed with mean length of 17.8 cm (7-24 cm) and mean diameter 25.6 mm (18-36 mm). Stent re-insertion was needed in 7 patients (9 procedure), while 6 patients required percutaneous collection drainage and 3 patients required endoscopic glue injection with clipping. Two stent removal procedures were carried out under endoscopic visualization after failed stent capture under fluoroscopy, while the remaining stents were successfully removed by interventional radiology. Results Stent placement was technically successful in all patients. Stent migration occurred in 6 patients (50%). There is a tendency for stent migration with shorter stent length (R= -0.557, p=0.008). The mean duration of stenting was 60.5 days (14-137 days). All patients underwent stent removal and resumed oral intake with no recurrence of leak at a mean follow up time of 190 days (14-410 days). Complications included gastrointestinal bleeding (n=1), proximal esophageal stricture (n=1) and stent occlusion (n=1). Conclusion Gastroesophageal stenting as a primary measure after diagnosis of early post sleeve gastrectomy leak appears to offer a safe and effective alternative option in obviating repeat surgical interventions. Minimally invasive interventions may still be required for the management of persistent leak. PMID:27874149

  12. Evaluation of Polyurethane Nasolacrimal Duct Stents: In Vivo Studies in New Zealand Rabbits

    SciTech Connect

    Wilhelm, K.E. Grabolle, B.; Urbach, H.; Tolba, R.; Schild, H.; Paulsen, F.

    2006-10-15

    The purpose of this study was to evaluate the radiographic and biological effects of different polyurethane nasolacrimal duct stents in an animal model. Fifteen polyurethane nasolacrimal duct stents (n = 5 mushroom-type stents, n = 5 newly designed S-shaped TearLeader stents without hydrophilic coating, and n = 5 S-shaped TearLeader stents with hydrophilic coating) were implanted in the nasolacrimal ducts of eight unaffected New Zealand rabbits. One nasolacrimal system served as control. Clinical and radiographic follow-up was performed at 1-, 2-, and 4-week intervals, then after a 3-month interval, after which the animals were euthanized. All stents were implanted without major periprocedural complications. The stents proved to be patent by the end of the procedure. During follow-up, all mushroom-type stents were occluded at 4 weeks. None of these stents opened to forced irrigation. Clinically, all rabbits demonstrated severe dacryocystitis. Three out of five TearLeader stents without hydrophilic coating were blocked at 4 weeks; one out of five was open to irrigation. Best results were observed in the stent group with hydrophilic coating. Follow-up dacryocystography demonstrated patent stents in nasolacrimal ducts of all animals after 4 weeks. In only one of five cases, the coated stent became partially occluded after 2 months. These animals were free of clinical symptoms. After 3 months, at least three out of five stents still opened to forced irrigation and only one stent was completely blocked. Dislocation of the stents was not observed. Refinement of the stent surface and stent design improves the results of nasolacrimal duct stenting in this animal model. Implantation of hydrophilic-coated S-shaped stents is highly superior to conventional mushroom-type stents and noncoated stent types. Hydrophilic coating seems to prevent foreign-body reactions, resulting in maximized stent patency.

  13. A Comparison of Peri-Procedural Myocardial Infarction between Paclitaxel-Coated Balloon and Drug-Eluting Stent on De Novo Coronary Lesions

    PubMed Central

    Her, Ae-Young; Cho, Kyoung-Im; Singh, Gillian Balbir; Garg, Scot; Kim, Yong Hoon; Koo, Bon-Kwon

    2017-01-01

    Purpose This study compared the impact of paclitaxel-coated balloons (PCB) or drug eluting stents (DES) on peri-procedural myocardial infarction (PMI) on de novo coronary lesion in stable patients. Materials and Methods In this observational study, we compared the incidence of PMI amongst patients with single vessel de novo coronary lesions who underwent treatment with a PCB or DES. Propensity score-matching analysis was used to assemble a cohort of patients with similar baseline characteristics. PMI was classified as myocardial infarction occurring within 48 hours after percutaneous coronary intervention with a threshold of 5 x the 99th percentile upper reference limit of normal for creatine kinase-myocardial band (CK-MB) or troponin T (TnT). Results One hundred four patients (52 receiving PCB and 52 receiving DES) were enrolled in this study. The peak mean values of CK-MB and TnT were significantly higher in the DES group. There was a significantly higher rate of PMI in the DES group (23.1% vs. 1.9%, p=0.002). Total occlusion of the side-branch occurred in two patients treated with DES, while no patients treated with PCB. In multivariable analysis, DES was the only independent predictor of PMI compared with PCB (odds ratio 42.85, 95% confidence interval: 3.44–533.87, p=0.004). Conclusion Treatment with a PCB on de novo coronary lesion might be associated with a significant reduction in the risk of PMI compared to DES. PMID:27873501

  14. The burden of chronic ureteral stenting in cervical cancer survivors

    PubMed Central

    Fan, Yunhua; Jarosek, Stephanie; Elliott, Sean P.

    2017-01-01

    ABSTRACT Purpose Ureteral obstruction in cervical cancer occurs in up to 11% of patients, many of whom undergo ureteral stenting. Our aim was to describe the patient burden of chronic ureteral stenting in a population-based cohort by detailing two objectives: (1) the frequency of repeat procedures for ureteral obstruction; and, (2) the frequency of urinary adverse effects (UAEs) (e.g., lower urinary tract symptoms, flank pain). Materials and Methods From SEER-Medicare, we identified 202 women who underwent ureteral stent placement prior to or following cervical cancer treatment. The frequency of repeat procedures and rate ratios were compared between treatment modalities. The rates and rate ratios of UAEs were compared between our primary cohort (stent + cervical cancer) and the following groups: no stent + cervical cancer, stent + no cancer, and no stent + no cancer. The “no cancer” group was drawn from the 5% Medicare sample. Results 117/202 women (58%) underwent >1 stent procedure. The frequency of additional procedures was significantly higher in patients who received radiation as part of their treatment. UAEs were very common in women with stent + cancer. The rate of UTI was 190 (per 100 person-years), 67 for LUTS, 42 for stones, and 6 for flank pain. These rates were 3-10 fold higher than in the no stent + no cancer control group; rates were also higher than in the no stent + cancer and the stent + no cancer women. Conclusions The burden of disease associated with ureteral stents is higher than expected and urologists should be actively involved in stent management, screening for associated symptoms and offering definitive reconstruction when appropriate. PMID:27649113

  15. Carotid Artery Stenting versus Endarterectomy

    PubMed Central

    Gahremanpour, Amir; Perin, Emerson C.; Silva, Guilherme

    2012-01-01

    For about 2 decades, investigators have been comparing carotid endarterectomy with carotid artery stenting in regard to their effectiveness and safety in treating carotid artery stenosis. We conducted a systematic review to summarize and appraise the available evidence provided by randomized trials, meta-analyses, and registries comparing the clinical outcomes of the 2 procedures. We searched the MEDLINE, SciVerse Scopus, and Cochrane databases and the bibliographies of pertinent textbooks and articles to identify these studies. The results of clinical trials and, consequently, the meta-analyses of those trials produced conflicting results regarding the comparative effectiveness and safety of carotid endarterectomy and carotid stenting. These conflicting results arose because of differences in patient population, trial design, outcome measures, and variability among centers in the endovascular devices used and in operator skills. Careful appraisal of the trials and meta-analyses, particularly the most recent and largest National Institutes of Healthsponsored trial (the Carotid Revascularization Endarterectomy vs Stenting Trial [CREST]), showed that carotid stenting and endarterectomy were associated with similar rates of death and disabling stroke. Within the 30-day periprocedural period, carotid stenting was associated with higher risks of stroke, especially for patients aged >70 years, whereas carotid endarterectomy was associated with a higher risk of myocardial infarction. The slightly higher cost of stenting compared with endarterectomy was within an acceptable range by cost-effectiveness standards. We conclude that carotid artery stenting is an equivalent alternative to carotid endarterectomy when patient age and anatomy, surgical risk, and operator experience are considered in the choice of treatment approach. PMID:22949763

  16. Iliocaval Confluence Stenting for Chronic Venous Obstructions

    SciTech Connect

    Graaf, Rick de; Wolf, Mark de; Sailer, Anna M.; Laanen, Jorinde van Wittens, Cees; Jalaie, Houman

    2015-10-15

    PurposeDifferent techniques have been described for stenting of venous obstructions. We report our experience with two different confluence stenting techniques to treat chronic bi-iliocaval obstructions.Materials and MethodsBetween 11/2009 and 08/2014 we treated 40 patients for chronic total bi-iliocaval obstructions. Pre-operative magnetic resonance venography showed bilateral extensive post-thrombotic scarring in common and external iliac veins as well as obstruction of the inferior vena cava (IVC). Stenting of the IVC was performed with large self-expandable stents down to the level of the iliocaval confluence. To bridge the confluence, either self-expandable stents were placed inside the IVC stent (24 patients, SECS group) or high radial force balloon-expandable stents were placed at the same level (16 patients, BECS group). In both cases, bilateral iliac extensions were performed using nitinol stents.ResultsRecanalization was achieved for all patients. In 15 (38 %) patients, a hybrid procedure with endophlebectomy and arteriovenous fistula creation needed to be performed because of significant involvement of inflow vessels below the inguinal ligament. Mean follow-up was 443 ± 438 days (range 7–1683 days). For all patients, primary, assisted-primary, and secondary patency rate at 36 months were 70, 73, and 78 %, respectively. Twelve-month patency rates in the SECS group were 85, 85, and 95 % for primary, assisted-primary, and secondary patency. In the BECS group, primary patency was 100 % during a mean follow-up period of 134 ± 118 (range 29–337) days.ConclusionStenting of chronic bi-iliocaval obstruction shows relatively high patency rates at medium follow-up. Short-term patency seems to favor confluence stenting with balloon-expandable stents.

  17. Use of a New Hybrid Heparin-Bonded Nitinol Ring Stent in the Popliteal Artery: Procedural and Mid-term Clinical and Anatomical Outcomes

    SciTech Connect

    Parthipun, Aneeta; Diamantopoulos, Athanasios; Kitrou, Panagiotis; Padayachee, Soundrie; Karunanithy, Narayan; Ahmed, Irfan; Zayed, Hany; Katsanos, Konstantinos E-mail: katsanos@med.upatras.gr

    2015-08-15

    PurposeTo report the immediate and mid-term clinical and anatomical outcomes of a novel, hybrid, heparin-bonded, nitinol ring stent (TIGRIS; Gore Medical) when used for the treatment of lesions located in the popliteal artery.Materials and MethodsThis was a prospective single-centre registry. Patients eligible for inclusion were individuals suffering from symptomatic popliteal arterial occlusive disease (Rutherford–Becker stage 3–6; P1–P3 segments) and treated with placement of the TIGRIS stent(s). Patients were prospectively scheduled for clinical review and duplex ultrasound follow-up after 6 and 12 months. Outcome measures included immediate technical success, primary vessel patency, in-stent binary restenosis (evaluable by Duplex at 50 % threshold; PSVR > 2.0), freedom from target lesion revascularization (TLR) and amputation-free survival (AFS) estimated by Kaplan–Meier (K–M) survival analysis. Cox proportional-hazards regression analysis was also performed to adjust for confounders and search for independent predictors of outcomes.ResultsFrom August 2012 to March 2014, a total of 54 popliteal TIGRIS stents were implanted in 50 limbs of 48 patients (27 men and 21 women; mean age 76.0 ± 1.7 years). Median Rutherford–Becker stage was five at baseline and 37/50 (74.0 %) were chronic total occlusions. Technical success was achieved in all cases (100 %). Stented lesion length was 114.2 ± 36.9 mm (range 6–20 cm). Median follow-up was 11.8 ± 0.8 months. After 12 months, primary patency of the TIGRIS stent was 69.5 ± 10.2 % with an 86.1 ± 5.9 % freedom from TLR and 87 ± 5.0 % AFS (K–M estimates).ConclusionThe TIGRIS hybrid heparin-bonded nitinol ring stent is a safe and effective endovascular option for complex occlusive disease of the popliteal artery.

  18. A Case of Late Femoral Pseudoaneurysm Caused by Stent Disconnection

    SciTech Connect

    Rivolta, Nicola; Fontana, Federico; Piffaretti, Gabriele Tozzi, Matteo; Carrafiello, Gianpaolo

    2010-10-15

    We present the case of a late superficial femoral artery stent disconnection causing an asymptomatic pseudoaneurysm successfully treated with a stent-graft. A 67-year-old female was referred to our department for evaluation of claudication of the left lower limb and was diagnosed to have a total occlusion of the superficial femoral artery. Three nitinol stents were used to revascularize this artery. At 48 months, duplex-ultrasonography control revealed the presence of a 45-mm saccular femoral dilatation; X-rays and CT angiography showed fractures of the proximal stents and the presence of a pseudoaneurysm at the site of the distal stents disconnection. The pseudoaneurysm was excluded using two stent-grafts. We conclude that patients and surgeons should be aware of structural complications with all stents. Rigorous follow-up controls should be mandatory. Endovascular repair proved to be feasible and durable to manage a previous endovascular procedure.

  19. Direct coronary stenting by transradial approach: rationale and technical issues.

    PubMed

    Burzotta, Francesco; Hamon, Martial; Trani, Carlo; Kiemeneij, Ferdinand

    2004-10-01

    Direct stent implantation using radial approach represents to date the less invasive, less traumatic strategy to perform a percutaneous coronary intervention, rendering its adoption an attraction for many interventional cardiologists. A growing series of reports suggests the feasibility of transradial direct stenting in a variety of clinical situations. Here we discuss the main advantages of the adoption of this technique. Moreover, a detailed analysis of the technical issues specifically related with each phase of transradial direct stenting procedures is reported.

  20. Subacute Drug-Eluting Stent Thrombosis Caused by Stent Underexpansion: Evaluation by Optical Coherence Tomography

    PubMed Central

    Martín-Reyes, Roberto; Jiménez-Valero, Santiago; Navarro, Felipe; Moreno, Raúl

    2011-01-01

    We present the case report of a patient presenting with ST segment elevation myocardial infarction due to a subacute drug-eluting stent trombosis within the proximal segment of the left circumflex artery (LCX). Six days before a total chronic occlusion was treated at the mid segment of the LCX by overlapping two drug-eluting stents. Optical coherence tomography (OCT) was helpful to demonstrate stent underexpansion of the overlaping segment as the main mechanism of early stent thrombosis. This case is illustrative about the potential role of OCT to identify the mechanisms of ST and thus guiding the PCI procedure. Moreover, our case shows the capability of the Imagewire to cross a severe stenosis due to stent underexpansion that could not be crossed by the IVUS catheter. PMID:21423540

  1. Palliation of Pyloric Stenosis Caused by Gastric Cancer Using an Endoscopically Placed Covered Ultraflex Stent: Covered Stent Inside an Occluded Uncovered Stent

    SciTech Connect

    Nakamura, Toshifumi; Kitagawa, Mutsuo; Takehira, Yasunori; Yamada, Masami; Nishiwaki, Yoshiro; Nakamura, Hirotoshi

    2000-07-15

    A 71-year-old man developed pyloric stenosis caused by gastric cancer. Vomiting and nausea resolved after the insertion of an uncovered Ultraflex stent (length 10 cm, inner diameter 18u23 mm) through a 7-cm-long stenosis, and the patient was able to eat a soft diet. After 6 weeks, stent occlusion occurred due to tumor ingrowth and accumulation of food residue. Endoscopic observation showed a very narrow residual lumen. A covered Ultraflex stent (length 10 cm, inner diameter 18u23 mm) was inserted through the first stent and expanded to its maximum diameter over the next 2 days. The patient's vomiting and nausea improved rapidly. He died 6 months after the second stenting procedure, from metastatic tumor spread, having remained free of nausea and vomiting. In this case, a covered metallic stent prevented tumor ingrowth and maintained gastrointestinal patency.

  2. Procedural and follow-up outcomes among patients undergoing successful recanalisation of coronary chronic total occlusions using biolimus drug-eluting stents.

    PubMed

    Saraf, S; Cockburn, J; Ferreira, I; Hopkins, S; Hildick-Smith, D

    2014-07-01

    This study aimed at evaluating the outcome of Biolimus eluting stent (BES) implantation in the treatment of chronic total coronary occlusions (CTO). We identified patients who underwent successful angioplasty for a CTO lesion with ≥1 BES between June 2008 and March 2012. All patients were followed up for major adverse cardiac events (MACE), which comprised death, non-fatal myocardial infarction (MI), cerebrovascular accident, target vessel revascularization (TVR), target lesion revascularization (TLR) and stent thrombosis. 125 patients underwent successful CTO angioplasty with ≥1 Biolimus-eluting stents. Mean age was 63.8 ± 12.0 years, and 82.4 % were males. Lesion location was right coronary artery (n = 80, 64 %), left anterior descending artery (n = 35, 28 %) and left circumflex artery (n = 10, 8 %). During follow-up of 579 ± 293 days, all cause mortality was n = 8 (6.4 %) patients, non-fatal MI was n = 3 (2.4 %), TVR was n = 3 (2.4 %) and TLR was n = 1 (0.8 %). Overall MACE was, therefore, n = 15 (12 %). BES is safe and effective in treatment of CTO lesions, with a low rate of major adverse cardiovascular events during follow-up.

  3. Simultaneous Thrombosis of Two Drug-Eluting Stents After Discontinuation of Dual Antiplatelet Therapy for a Day

    PubMed Central

    Chen, Hung Yi

    2012-01-01

    Stent thrombosis is rare but can lead to potential severe consequence. The incidence is relative higher in drug-eluting sent than bare-metal stent implantation. Dual antiplatelet therapy is the major treatment to avoid early and late stent thrombosis. Simultaneous two stents thrombosis is rare. Although mechanical or/and procedure factors may predispose to stent thrombosis occurred, simultaneous two stents thrombosis implies possibly ineffective antiplatelet therapy. We report a case with simultaneous two stent thrombosis and complicated with cardiogenic shock after lost antiplatelet therapy for one day. We try to emphasize to properly educate patients about the importance of continuous drug use to avoid catastrophic tragedy.

  4. Complications during renal artery stent placement for atherosclerotic ostial stenosis

    SciTech Connect

    Beek, Frederik J. A.; Kaatee, Robert; Beutler, Jaap J.; Ven, Peter J. van der; Mali, Willem P. T. M.

    1997-05-15

    Purpose. To describe short-term complications during stent placement for atherosclerotic renal artery ostial stenosis. Methods. Sixty-one arteries in 50 patients were treated with Palmaz stents. Nineteen patients had a single functioning kidney, 23 had a bilateral stenosis, which was stented bilaterally in 11, and 8 had a unilateral stenosis. The complications were grouped as those related to the catheterization procedure, those related to stent placement, and those possibly related to either category. The complications were divided into those with severe clinical significance (SCS), those with minor clinical significance (MCS), and radiological-technical complications (RTC). The stent placement procedures were ordered chronologically according to examination date and the complications were tabulated per group of 10 patients. Results. Five (10%) SCS, 5 (10%) MCS, and 8 (16%) RTC occurred in 50 patients. The catheterization procedure led to 2 SCS, 3 MCS, and 1 RTC. Stent placement gave rise to 7 RTC. Three SCS and 2 MCS could have been related to either catheterization or stent placement. More SCS occurred in the first group of 10 patients than in the following groups. Conclusion. Renal artery stent placement for atherosclerotic ostial stenosis has a considerable complication rate and a learning curve is present. The complications related to the actual stent placement were without clinical consequences.

  5. iStent trabecular micro-bypass stent for open-angle glaucoma

    PubMed Central

    Le, Kim; Saheb, Hady

    2014-01-01

    Trabecular micro-bypass stents, commonly known as iStents, are micro-invasive glaucoma surgery (MIGS) devices used to treat open-angle glaucoma. Like other MIGS procedures that enhance trabecular outflow, the iStent lowers intraocular pressure (IOP) by creating a direct channel between the anterior chamber and Schlemm’s canal. iStents are typically implanted at the time of phacoemulsification for patients with open-angle glaucoma and visually significant cataracts. This review summarizes the published data regarding the efficacy, safety, and cost considerations of trabecular micro-bypass stents. Most studies found statistically significant reductions in mean IOP and ocular medication use after combined phacoemulsification with single or double iStent implantation. The devices were found to be very safe, with a safety profile similar to that of cataract surgery. Complications were infrequent, with the most common complications being temporary stent obstruction or malposition, which resolved with observation or secondary procedures. Future studies are needed to evaluate long-term outcomes, patient satisfaction, cost effectiveness, and expanded indications. PMID:25284980

  6. Pulmonary Arterial Stent Implantation in an Adult with Williams Syndrome

    SciTech Connect

    Reesink, Herre J.; Henneman, Onno D. F.; Delden, Otto M. van; Biervliet, Jules D.; Kloek, Jaap J.; Reekers, Jim A.; Bresser, Paul

    2007-07-15

    We report a 38-year-old patient who presented with pulmonary hypertension and right ventricular dysfunction due to pulmonary artery stenoses as a manifestation of Williams syndrome, mimicking chronic thromboembolic pulmonary hypertension. The patient was treated with balloon angioplasty and stent implantation. Short-term follow-up showed a good clinical result with excellent patency of the stents but early restenosis of the segments in which only balloon angioplasty was performed. These stenoses were subsequently also treated successfully by stent implantation. Stent patency was observed 3 years after the first procedure.

  7. Radiological Management of Superior Vena Caval Stent Migration and Infection

    SciTech Connect

    Srinathan, Sadeesh McCafferty, Ian; Wilson, Ian

    2005-01-15

    We report a case of venous obstruction secondary to Hodgkin's lymphoma. Multiple Wallstents were inserted into the superior vena cava to relieve obstructive symptoms secondary to tumor. This procedure was complicated by stent migration into the right ventricle and a presumed stent infection. We describe the percutaneous management of these complications and discuss the issues surrounding the use of stents in this setting. We conclude that these complications can be managed percutaneously. However, the technical details of stent placement are essential in minimizing complications of this type.

  8. Insulin-treated diabetes mellitus: An important, actionable risk marker after coronary stenting.

    PubMed

    Hillegass, William B

    2016-01-01

    Insulin treatment for diabetes is a simple but important risk marker for doubled adjusted death and myocardial infarction rates and tripled stent thrombosis risk after coronary stenting. Insulin treatment does not predict meaningfully increased major bleeding or additional revascularization procedures after drug eluting coronary stent implantation. Third generation P2 Y12 receptor antagonists substantially lower risk of events in diabetics after stenting with insulin treated diabetics having twice the magnitude of benefit of diabetics not needing insulin.

  9. Nasolacrimal Stenting: Toward Improving Outcomes with a Simple Modification of the Song Stent

    SciTech Connect

    Lanciego, Carlos Miguel, Silvia De; Padilla, Manuel; Perea, Miguel; Rodriguez-Merlo, Rufo; Garcia-Garcia, Lorenzo

    2006-08-15

    The purpose of this study was to evaluate, in a prospective, single-center study, the effectiveness of Song's polyurethane stents, modified 'in-house,' in the percutaneous management of epiphora. Patients (n = 170; age range 18-83, mean = 64; 50 male, 120 female) with severe epiphora had the modified stents inserted (183 eyes/195 stents) to treat unilateral/bilateral and complete/partial obstruction of the nasolacrimal system. The etiology of the obstruction was idiopathic in 119 cases (61%) and chronic dacryocystitis in 76 (39%). The set designed by Song was used in all patients but modified by us such that the extreme end is cone-shaped. The original technique was slightly modified by us and the procedure was conducted on an outpatient basis. The initial technical success rate of stent placement was 97%. Resolution of epiphora was complete in 180 eyes and partial in 3. On follow-up (mean = 18 months; range: 2 days to 24 months), 165 of 195 stents (85%) remained patent. Primary patency rates at follow-up were 86%, 84%, 84%, and 79% in the first 6 months, second and third 6 months, and the present (24 months), respectively. Stents became obstructed in 30 patients, but all but 2 were easily withdrawn and 20 of these patients remained asymptomatic for a mean of 14 months (secondary patency of 67%). Following stent removal, the withdrawn stent was replaced with a new stent in the same intervention on 14 occasions. In another six cases, patency was re-established without the need of a second stent. The procedure is simple and safe, both in stent insertion as well as in mechanical de-blocking and withdrawal when occluded. Success was >80 % in the short term (1-year follow-up). Stenting failure does not preclude other treatment because with the modification that we had introduced, the extreme end of the stent becomes more accessible to mechanical de-blocking, withdrawal, and relocation. The levels of primary and secondary patencies are promising and warrant more

  10. Flexible ureteroscopy for renal stone without preoperative ureteral stenting shows good prognosis

    PubMed Central

    Zhang, Jiaqiao; Xu, Chuou; He, Deng; Lu, Yuchao; Hu, Henglong; Qin, Baolong; Wang, Yufeng; Wang, Qing; Li, Cong; Liu, Jihong

    2016-01-01

    Purpose To clarify the outcome of flexible ureteroscopy (fURS) for management of renal calculi without preoperative stenting. Methods A total of 171 patients who received 176 fURS procedures for unilateral renal stones were reviewed. All procedures were divided into two groups depending on whether they received ureteral stenting preoperatively. Baseline characteristics of patients, stone burden, operation time, stone-free rates, and complications were compared between both groups. Results Successful primary access to the renal pelvis was achieved in 104 of 114 (91.2%) patients without preoperative stenting, while all procedures with preoperative stenting (n = 62) were successfully performed. A total of 156 procedures were included for further data analysis (56 procedures in stenting group and 100 in non-stenting group). No significant differences was found regardless of a preoperative stent placement in terms of stone-free rate (73.2% with stenting vs. 71.0% without, P = 0.854), operative time (70.4 ± 32.8 with stenting vs. 70.2 ± 32.1 without, P = 0.969). Conclusions fURS for management of renal stone without preoperative ureteral stenting are associated with well outcome in short term follow-up. Our study may help patients and doctors to decide if an optional stent is placed or not. PMID:27917317

  11. Impact of Coronary Plaque Characteristics on Late Stent Malapposition after Drug-Eluting Stent Implantation

    PubMed Central

    Hong, Sung-Jin; Kim, Byeong-Keuk; Shin, Dong-Ho; Kim, Jung-Sun; Ko, Young-Guk; Choi, Donghoon; Jang, Yangsoo

    2015-01-01

    Purpose To evaluate the impact of pre-procedural coronary plaque composition assessed by virtual histology intravascular ultrasound (VH-IVUS) on late stent malapposition assessed by optical coherence tomography (OCT) following drug-eluting stent (DES) implantation. Materials and Methods The study population consisted of 121 patients (121 lesions) who underwent both pre-procedural VH-IVUS and follow-up OCT after DES implantation. The association between pre-procedural plaque composition [necrotic core (NC), dense calcium (DC), fibrotic (FT), and fibro-fatty (FF) volumes] assessed by VH-IVUS and late stent malapposition (percent malapposed struts) or strut coverage (percent uncovered struts) assessed by follow-up OCT was evaluated. Results Pre-procedural absolute total NC, DC, FT, and FF plaque volumes were 22.9±19.0, 7.9±9.6, 63.8±33.8, and 16.5±12.4 mm3, respectively. At 6.3±3.1 months post-intervention, percent malapposed and uncovered struts were 0.8±2.5% and 15.3±16.7%, respectively. Pre-procedural absolute total NC and DC plaque volumes were positively correlated with percent malapposed struts (r=0.44, p<0.001 and r=0.45, p<0.001, respectively), while pre-procedural absolute total FT plaque volume was weakly associated with percent malapposed struts (r=0.220, p=0.015). Pre-procedural absolute total DC plaque volume was the only independent predictor of late stent malapposition on multivariate analysis (β=1.12, p=0.002). There were no significant correlations between pre-intervention plaque composition and percent uncovered struts. Conclusion Pre-procedural plaque composition was associated with late stent malapposition but not strut coverage after DES implantation. Larger pre-procedural absolute total DC plaque volumes were associated with greater late stent malapposition. PMID:26446634

  12. Direct coronary stent implantation: safety, feasibility, and predictors of success of the strategy of direct coronary stent implantation.

    PubMed

    Laarman, G; Muthusamy, T S; Swart, H; Westendorp, I; Kiemeneij, F; Slagboom, T; van der Wieken, R

    2001-04-01

    This prospective study was designed to evaluate the feasibility, safety, predictive factors of success, and 6-month follow-up of stent implantation without balloon predilatation (direct stenting) in 250 patients undergoing elective stent implantation. Balloon dilatation prior to stent implantation was a prerequisite to facilitate passage and deployment of the stent. Stent technology has changed tremendously, resulting in stents with improved properties, which may allow stent placement without prior balloon dilatation. Patients with coronary lesions suitable for elective stent implantation were included in this trial. Coronary interventions were undertaken predominantly via the transradial route using 6 Fr guiding catheters. Direct stent implantation was attempted using AVE GFX II coronary stent delivery systems. Upon failure, predilatation was undertaken before reattempting stent implantation. Patient data and ECGs were obtained from case records and from personal or telephone interviews 6 months after the procedure. Values were presented as mean +/- standard deviation. Student's t-test, two-tailed at 5% level of significance, was used to compare the difference of two means. Multivariate logistic regression analysis was performed to establish predictive factors for failure of direct stenting. Two hundred and sixty-six direct stent implantations were attempted in 250 patients. Direct stenting was successful in 226 (85%) cases. Out of 40(15%) cases where direct stenting failed, balloon predilatation facilitated stent implantation in 39. In one lesion, stent implantation was not possible despite adequate predilatation. Predictive factors for failure of direct stenting on multivariate analysis were LCx lesions (P < 0.01), complex lesions (P < 0.01), and longer stents (P < 0.001). Minimal luminal diameter and percentage diameter stenosis of lesions in the successful and the failure group were not significantly different (0.94 +/- 0.39 mm vs. 0.84 +/- 0.41 mm, P = NS

  13. Stenting of the Lower Gastrointestinal Tract: Current Status

    SciTech Connect

    Katsanos, Konstantinos; Sabharwal, Tarun Adam, Andreas

    2011-06-15

    Colon obstruction due to colorectal cancer is a major surgical emergency. Patients with acute bowel obstruction are usually poor surgical candidates with 10-20% operative mortality and 40-50% operative morbidity rates. Colorectal stenting is an image-guided, minimally invasive procedure, and typical indications include either palliation of inoperable malignant disease or temporary bowel decompression as a bridge to surgery. Colorectal stenting allows the patient to recover before definite elective surgical resection, reducing perioperative morbidity and mortality, overall hospital stay, and associated health care costs. Palliative stenting improves quality of life compared to surgery. A concise review is provided of contemporary stenting practice of the lower gastrointestinal tract, the colon in particular, and both palliative and preoperative adjuvant procedures are evaluated in terms of relevant patient oncology, insertion technique, available stent designs, technical and clinical outcomes, associated complications, and cost-benefit analysis.

  14. Residual stresses in coronary artery stents.

    PubMed

    Möller, D; Reimers, W; Pyzalla, A; Fischer, A

    2001-01-01

    In western industrial countries, coronary heart disease is the most common cause of death. The reason is a coronary sclerosis, which by the generation of plaques narrows the inner lumen of an artery and, thus, deteriorates the blood supply. This leads to symptoms like burning pain or increased pressure in the chest, and finally to an under supply and damage of the heart muscle. In order to keep those portions of arteries that are covered by a plaque open, the stent technique was developed in the 1980s and is increasingly used since about 13 years. These stents are usually made of wires or of a slotted tube and are of two kinds: self-expanding and balloon expanding. Both types are implanted after being mounted on a catheter and expanded in the desired position. Self-expanding stents make use of the elastic deformation, while the other group of stents are expanded by a balloon, which brings about a plastic deformation of certain regions of the stent structure. Thus, after implantation, parts of these stents undergo two steps of distinct plastic deformation. First during compression, which is necessary for the mounting procedure on the catheter (crimping), and second during expansion for implantation. In this article, the residual stresses generated during crimping and expansion are presented and discussed. These stresses are stored in the structure of a portion of a stent after implantation and are superimposed on those stresses generated by the more than 700 million cyclic heart beats during the patient's life. This work is a part of several interdisciplinary research projects by the authors in order to gain reliable fail-safe criteria for the static and cyclic mechanical properties of coronary stents.

  15. Angiographic restenosis in ephesos coronary stents: experience from a large medical center in Ankara, Turkey.

    PubMed

    Altin, Timucin; Berkalp, Berkten; Ozdol, Cagdas; Akyurek, Omer; Sayin, Tamer; Kervancioglu, Celal; Oral, Dervis; Erol, Cetin

    2008-01-01

    Coronary stent restenosis, which emerges in late periods after implantation, has not been completely abolished. Our aim was to investigate the restenosis rates of Ephesos coronary stents. In all, 96 patients (66 men) with 135 Ephesos coronary stents were included. Control angiograms were performed after 160 +/- 60 days. Quantitative coronary analysis was performed during the procedure and control angiogram. The stents were divided into 2 groups according to the presence or absence of restenosis. Groups were compared with clinical and angiographic variables. Restenosis was observed in 31 (23%) of 135 stents. Preprocedure percent diameter stenosis was higher (P = .02), whereas minimum lumen diameter ( P = .02), mean age (P < .001), and hypertension incidence ( P = .043) was less, and there was a trend toward smaller stent size ( P = .054) in the restenosis group. By multivariate analysis, age <50 years (P < .001) and stent size <3.0 mm (P = .016) were independent predictors of restenosis. Ephesos coronary stents seems to have acceptable restenosis rates.

  16. Patient-specific modeling of intracranial aneurysmal stenting

    NASA Astrophysics Data System (ADS)

    Appanaboyina, Sunil; Mut, Fernando; Löhner, Rainald; Putman, Christopher M.; Cebral, Juan R.

    2007-03-01

    Simulating blood flow around stents in intracranial aneurysms is important for designing better stents and to personalize and optimize endovascular stenting procedures in the treatment of these aneurysms. However, the main difficulty lies in the generation of acceptable computational grids inside the blood vessels and around the stents. In this paper, a hybrid method that combines body-fitted grid for the vessel walls and adaptive embedded grids for the stent is presented. Also an algorithm to map a particular stent to the parent vessel is described. These approaches tremendously simplify the simulation of blood flow past these devices. The methodology is evaluated with an idealized stented aneurysm under steady flow conditions and demonstrated in various patient-specific cases under physiologic pulsatile flow conditions. These examples show that the methodology can be used with ease in modeling any patient-specific anatomy and using different stent designs. This paves the way for using these techniques during the planning phase of endovascular stenting interventions, particularly for aneurysms that are difficult to treat with coils or by surgical clipping.

  17. Prophylactic stenting for esophageal stricture prevention after endoscopic submucosal dissection

    PubMed Central

    Shi, Ke-Da; Ji, Feng

    2017-01-01

    Endoscopic submucosal dissection (ESD) of superficial esophageal cancer has been increasingly used as an alternative to surgery because it is minimally invasive and has a high rate of en bloc resection. However, a high rate of esophageal stricture is observed after ESD for large lesions, which can dramatically decrease the patient’s quality of life. Stricture prevention is necessary to allow for endoscopic therapy to expand. We, herein, review the most recent evidence and discuss the role of the metallic self-expandable stent and the biodegradable stent in esophageal stricture prevention. Limited studies suggested that prophylactic stenting could reduce the stricture rate without increasing the number of complications. In addition, the number of bougie dilation procedures was significantly lower with stent placement. Esophageal stenting is a promising option for post-ESD stricture prevention. However, current evidence is too preliminary to formulate practice standards. Future studies are needed to further validate the efficacy and safety of prophylactic stenting and determine the best strategy for stricture prevention. Stent migration is the most common complication. A new stent that has advantages of a low migration rate and minimal tissue reaction will need to be developed. Therefore, randomized controlled trials with long-term follow-up periods are required before prophylactic stenting could be considered a valid option to prevent post-ESD stricture. PMID:28246466

  18. Treatment of Intra- and Extracranial Arterial Dissections Using Stents and Embolization

    SciTech Connect

    Joo, Jin Yang; Ahn, Jung Yong Chung, Young Sun; Han, In Bo; Chung, Sang Sup; Yoon, Pyeong Ho; Kim, Sang Heum; Choi, Eun Wan

    2005-06-15

    Purpose. To evaluate the safety and efficacy of stent placement for extracranial and intracranial arterial dissections. Methods. Eighteen patients underwent endovascular treatment of carotid and vertebral dissections using intraluminal stent placement. Five patients with arterial dissection were treated, 2 using one insertion of a single stent and 3 using placement of two stents. Patients with a dissecting aneurysm were treated as follows: 7 patients with insertion of one stent, 4 with placement of two stents, and 2 by stent-assisted Guglielmi detachable coil embolization. In the 18 patients in whom stenting was attempted, the overall success in reaching the target lesion was 94.4%. Of the 17 patients treated with stents, stent release and positioning were considered optimal in 16 (94%) and suboptimal in one (6%). In patients who underwent a successful procedure, all parent arteries were preserved. There were no instances of postprocedural ischemic attacks, new neurologic deficits, or new minor or major strokes prior to patient discharge. In follow up, all patients were assessed, using the modified Rankin scale, as functionally improved or of stable clinical status. The reduction in dissection-induced stenosis or pseudoaneurysm, the patency rate obtained at follow-up, and the lack of strokes (ischemic or hemorrhagic) suggest that stent placement offers a viable alternative to complex surgical bypass or reconstructive procedures. The long-term efficacy and durability of stent placement for arterial dissection remain to be determined in a larger series.

  19. Metallic Stents for Tracheobronchial Pathology Treatment

    SciTech Connect

    Serrano, Carolina; Laborda, Alicia; Lozano, Juan M.; Caballero, Hugo; Sebastian, Antonio; Lopera, Jorge; Gregorio, Miguel Angel de

    2013-12-15

    Purpose: To present the 7-year experience of the treatment of benign and malignant tracheobronchial stenoses using metallic stents. Patients and Methods: One hundred twenty-three stents were inserted in 86 patients (74 benign and 12 malignant stenoses). Ninety-seven stents were placed in the trachea and 26 in the bronchi. The procedures were performed under fluoroscopic and flexible bronchoscopic guidance with the patient under light sedation. In cases of severe stenotic lesions or obstructions, laser resection was performed before stent placement. Clinical and functional pulmonary data were recorded before and 3 months after the procedure. Follow-up involved clinical data and radiographic techniques at 48 h and at 1-, 3-, 6-, and 12-month intervals. Results: The technical success was 100 %. Dyspnea disappearance, forced expiratory volume in the first second, and pulmonary functional data improvement was observed in all patients (p < 0.001). Complications were detected in 23 patients (26.7 %). Mean follow-up time was 6.3 {+-} 1.2 months in patients with malignant lesions and 76.2 {+-} 2.3 months patients with in benign lesions. By the end of the study, 100 % of patients with malignant pathology and 6.7 % of patients with benign lesions had died. Conclusion: Endoluminal treatment of tracheobronchial stenosis with metallic stents is a therapeutic alternative in patients who are poor candidates for surgery. In unresectable malignant lesions, the benefit of metallic stenting is unquestionable. In benign lesions, the results are satisfactory, but sometimes other interventions are required to treat complications. New stent technology may improve these results.

  20. Double-Layered PTFE-Covered Nitinol Stents: Experience in 32 Patients with Malignant Esophageal Strictures

    SciTech Connect

    Park, Jung Gu; Jung, Gyoo-Sik Oh, Kyung Seung; Park, Seon-Ja

    2010-08-15

    We evaluated the effectiveness of a double-layered polytetrafluoroethylene (PTFE)-covered nitinol stent in the palliative treatment of malignant esophageal strictures. A double-layered PTFE-covered nitinol stent was designed to reduce the propensity to migration of conventional covered stent. The stent consists of an inner PTFE-covered stent and an outer uncovered nitinol stent tube. With fluoroscopic guidance, the stent was placed in 32 consecutive patients with malignant esophageal strictures. During the follow-up period, the technical and clinical success rates, complications, and cumulative patient survival and stent patency were evaluated. Stent placement was technically successful in all patients, and no procedural complications occurred. After stent placement, the symptoms of 30 patients (94%) showed improvement. During the mean follow-up of 103 days (range, 9-348 days), 11 (34%) of 32 patients developed recurrent symptoms due to tumor overgrowth in five patients (16%), tumor ingrowth owing to detachment of the covering material (PTFE) apart from the stent wire in 3 (9%), mucosal hyperplasia in 2 (6%), and stent migration in 1 (3%). Ten of these 11 patients were treated by means of placing a second covered stent. Thirty patients died, 29 as a result of disease progression and 1 from aspiration pneumonia. The median survival period was 92 days. The median period of primary stent patency was 190 days. The double-layered PTFE-covered nitinol stent seems to be effective for the palliative treatment of malignant esophageal strictures. We believe that the double-layer configuration of this stent can contribute to decreasing the stent's migration rate.

  1. Palliative stent implantation for coarctation in neonates and young infants

    PubMed Central

    Sreeram, Isabel; Sreeram, Narayanswami; Bennink, Gerardus

    2012-01-01

    Background: In selected neonates and infants, primary palliative stent implantation may be indicated for coarctation of the aorta. We describe our experience with this approach in five consecutive patients. Methods: Five neonates and infants (age range 6 to 68 days, gestation 33 to 38 weeks, weight range at procedure of between 1650 to 4000 g) underwent palliative stent implantation as primary therapy for coarctation of the aorta. Indications for primary stent implantation were varied. All procedures were performed by elective surgical cut down of the axillary artery. Standard coronary stents (diameter 4.5 to 5 mm, length 12 to 16 mm) were delivered via a 4F sheath. The axillary artery was repaired after removal of the sheath. Results: All procedures were acutely successful, and without procedural complications. All patients survived to hospital discharge. Four patients have subsequently undergone elective stent removal and surgical repair of the arch, at between 38 and 83 days following stent implantation. Complete stent removal was achieved in three patients. Over a follow-up ranging between 8 weeks and 36 months, none of the patients has had any further complications. Conclusions: This palliative approach is warranted in carefully selected patients. Long-term follow-up is required. PMID:23129903

  2. Esophagojejunal Anastomosis Fistula, Distal Esophageal Stenosis, and Metalic Stent Migration after Total Gastrectomy

    PubMed Central

    Al Hajjar, Nadim; Popa, Calin; Al-Momani, Tareg; Margarit, Simona; Graur, Florin; Tantau, Marcel

    2015-01-01

    Esophagojejunal anastomosis fistula is the main complication after a total gastrectomy. To avoid a complex procedure on friable inflamed perianastomotic tissues, a coated self-expandable stent is mounted at the site of the anastomotic leak. A complication of stenting procedure is that it might lead to distal esophageal stenosis. However, another frequently encountered complication of stenting is stent migration, which is treated nonsurgically. When the migrated stent creates life threatening complications, surgical removal is indicated. We present a case of a 67-year-old male patient who was treated at our facility for a gastric adenocarcinoma which developed, postoperatively, an esophagojejunostomy fistula, a distal esophageal stenosis, and a metallic coated self-expandable stent migration. To our knowledge, this is the first reported case of an esophagojejunostomy fistula combined with a distal esophageal stenosis as well as with a metallic coated self-expandable stent migration. PMID:25945277

  3. Esophagojejunal anastomosis fistula, distal esophageal stenosis, and metalic stent migration after total gastrectomy.

    PubMed

    Al Hajjar, Nadim; Popa, Calin; Al-Momani, Tareg; Margarit, Simona; Graur, Florin; Tantau, Marcel

    2015-01-01

    Esophagojejunal anastomosis fistula is the main complication after a total gastrectomy. To avoid a complex procedure on friable inflamed perianastomotic tissues, a coated self-expandable stent is mounted at the site of the anastomotic leak. A complication of stenting procedure is that it might lead to distal esophageal stenosis. However, another frequently encountered complication of stenting is stent migration, which is treated nonsurgically. When the migrated stent creates life threatening complications, surgical removal is indicated. We present a case of a 67-year-old male patient who was treated at our facility for a gastric adenocarcinoma which developed, postoperatively, an esophagojejunostomy fistula, a distal esophageal stenosis, and a metallic coated self-expandable stent migration. To our knowledge, this is the first reported case of an esophagojejunostomy fistula combined with a distal esophageal stenosis as well as with a metallic coated self-expandable stent migration.

  4. Status and Literature Review of Self-Expandable Metallic Stents for Malignant Colorectal Obstruction

    PubMed Central

    Cheung, Dae Young; Lee, Yong Kook

    2014-01-01

    Use of colorectal stents has increased dramatically over the last decades. Colorectal stents offer an alternative way to relieve fatal intestinal obstruction and can take place of emergency surgery, which associated with significant morbidity and mortality and a high incidence of stoma creation, to elective resection. Although there remain a few concerns regarding the use of stents as a bridge to surgical resection, use of self-expandable metallic stents for palliation in patients with unresectable disease has come to be generally accepted. Advantages of colorectal stents include acute restoration of luminal patency and allowance of time for proper staging and surgical optimization, and the well-known disadvantages are procedure-related complications including perforation, migration, and stent failure. General indications, procedures, and clinical outcomes as well as recent evidences regarding the use of colorectal stents will be discussed in this review. PMID:24570885

  5. High-Resolution CT and Angiographic Evaluation of NexStent Wall Adaptation

    SciTech Connect

    Nemes, Balazs Lukacs, Levente; Balazs, Gyoergy; Dosa, Edit; Berczi, Viktor; Huettl, Kalman

    2009-05-15

    Carotid stenting is a minimally invasive treatment for extracranial carotid artery stenosis. Stent design may affect technical success and complications in a certain subgroup of patients. We examined the wall adaptability of a new closed-cell carotid stent (NexStent), which has a unique rolled sheet design. Forty-one patients had 42 carotid arteries treated with angioplasty and stenting for internal carotid artery stenosis. The mean patient age was 65 {+-} 10 years. All patients underwent high-resolution computed tomographic angiography after the stent implantation. Data analysis included pre- and postprocedural stenosis, procedure complications, plaque calcification, and stent apposition. We reviewed the angiographic and computed tomographic images for plaque coverage and stent expansion. All procedures were technically successful. Mean stenosis was reduced from 84 {+-} 8% before the procedure to 15.7 {+-} 7% after stenting. Two patients experienced transient ischemic attack; one patient had bradycardia and hypotension. Stent induced kinking was observed in one case. Good plaque coverage and proper overlapping of the rolled sheet was achieved in all cases. There was weak correlation between the residual stenosis and the amount of calcification. The stent provides adequate expansion and adaptation to the tapering anatomy of the bifurcation.

  6. A direct nitinol stent delivery technique for endovascular treatment: a sheath-less stenting technique.

    PubMed

    Shintani, Yoshiaki; Kawasaki, Tomohiro; Fujimura, Takashi; Ishida, Kouichirou; Higuchi, Takanori; Kajiwara, Masataka; Fukuoka, Ryota; Orita, Yoshiya; Umeji, Kyoko; Koga, Hisashi; Koga, Nobuhiko

    2015-04-01

    Access site problems often cause serious complications in endovascular treatment. The aim of this study is to investigate whether a sheath-less nitinol stenting technique leads to reduce access site complications. This study was a single-center retrospective analysis of a prospectively maintained database. The study enrolled consecutive 98 patients with 111 lesions undergoing provisional stenting for de novo iliac artery or femoro-popliteal artery stenosis between August 2010 and November 2011. The patients were divided into two groups, a conventional procedure group and a sheath-less procedure group. The outcomes of this study were peri-procedural access site complications, initial success rate, procedure time, hemostatic time and bed-rest time. Forty-four lesions in 39 patients that treated using the sheath-less nitinol stent delivery technique were compared with 67 lesions in 59 patients treated using the conventional procedure. All procedures were successful. The incidence of pseudoaneurysm was significantly lower in the sheath-less procedure group than in the conventional procedure group (p = 0.043). However, there were no significant differences in any other complications. No significant difference was observed in the procedural time (p = 0.309). However, hemostatic time and bed-rest time were significantly shorter in the sheath-less procedure than in the conventional procedure (p < 0.0001). A sheath-less stenting technique reduced the access site incidence of pseudoaneurysm and did not increase other access site complications. Besides, this technique shortened hemostatic time and bed-rest time. The sheath-less stenting technique is considered to be a useful method for endovascular treatment.

  7. Meta-Analysis of Stenting versus Non-Stenting for the Treatment of Ureteral Stones

    PubMed Central

    Wang, Hai; Man, Libo; Li, Guizhong; Huang, Guanglin; Liu, Ning; Wang, Jianwei

    2017-01-01

    Background and aim Ureteroscopic lithotripsy (URL) and extracorporeal shock wave lithotripsy (ESWL) are two widely used methods for the treatment of ureteral stones. The need for ureteral stenting during these procedures is controversial. In this meta-analysis, we evaluated the benefits and disadvantages of ureteral stents for the treatment of ureteral stones. Methods Databases including PubMed, Embase and Cochrane library were selected for systematic review of randomized controlled trials (RCTs) comparing outcomes with or without stenting during URL and ESWL. Meta-analysis was performed using RevMan 5.3 and STATA 13.0 software. Results We identified 22 RCTs comparing stenting and non-stenting. The stented group was associated with longer operation time (WMD: 4.93; 95% CI: 2.07 to 7.84; p < 0.001), lower stone-free rate (OR: 0.55; 95% CI: 0.34 to 0.89; p = 0.01). In terms of complications, the incidence of hematuria (OR: 3.68; 95% CI: 1.86 to 7.29; p < 0.001), irritative urinary symptoms (OR: 4.40; 95% CI: 2.19 to 9.10; p < 0.001), urinary infection (OR: 2.23; 95% CI: 1.57 to 3.19; p < 0.001), and dysuria (OR: 3.90; 95% CI: 2.51 to 6.07; p < 0.001) were significantly higher in the stented group. No significant differences in visual analogue score (VAS), stricture formation, fever, or hospital stay were found between stenting and non-stenting groups. The risk of unplanned readmissions (OR: 0.63; 95% CI: 0.41 to 0.97; p = 0.04) was higher in the non-stented group. Conclusions Our analysis showed that stenting failed to improve the stone-free rate, and instead, it resulted in additional complications. However, ureteral stents are valuable in preventing unplanned re-hospitalization. Additional randomized controlled trials are still required to corroborate our findings. PMID:28068364

  8. Cost comparison between two modes of Palmaz Schatz coronary stent implantation: transradial bare stent technique vs. transfemoral sheath-protected stent technique.

    PubMed

    Kiemeneij, F; Hofland, J; Laarman, G J; van der Elst, D H; van der Lubbe, H

    1995-08-01

    Coronary Palmaz Schatz stent implantation is usually performed by using the sheath protected stent delivery system (SDS) via the percutaneous transfemoral route. However, downsizing of PTCA equipment made transradial coronary stenting feasible. Bare stent implantation, 6F technique, increased patient mobility, reduced vascular complications and reduced hospital stay may increase cost effectiveness of this novel technique. Two well-documented patient groups selected for elective single vessel and single lesion Palmaz Schatz stent implantation were retrospectively compared. Group A (transradial stenting; n = 35) was compared to Group B (transfemoral stenting; n = 25) derived from the Benestent population, included in our hospital. A comparison was made for three areas of interest: (1) procedural consumption of material (the number of guiding catheters, guidewires, balloon catheters and stents), (2) postprocedural need for diagnostic and therapeutic procedures for stent-related complications, and (3) duration of hospital stay. Differences between these subjects in Group A and B were translated to hospital costs. Although more guiding catheters were used in group A (1.69 +/- 0.87 vs. 1.08 +/- 0.28; P = 0.001), the use of the SDS contributed importantly to higher material costs in group B (cost reduction in group A; 13%). Less patients in group A required diagnostic (2 vs. 7; P = 0.027) and therapeutic (0 vs. 5; P = 0.01) procedures for bleeding complications (cost reduction; 93%). Hospitalization in Group A was shorter (6.4 +/- 4.7 vs. 11.6 +/- 9.9 days; P = 0.005), caused by early and safe mobilization, less vascular complications, and preprocedural adjustment on coumadin (cost reduction; 45%).(ABSTRACT TRUNCATED AT 250 WORDS)

  9. Outcomes of Prosthetic Hemodialysis Grafts after Deployment of Bare Metal versus Covered Stents at the Venous Anastomosis

    SciTech Connect

    Kim, Charles Y. Tandberg, Daniel J.; Rosenberg, Michael D.; Miller, Michael J.; Suhocki, Paul V.; Smith, Tony P.

    2012-08-15

    Purpose: To compare postintervention patency rates after deployment of bare metal versus covered stents across the venous anastomosis of prosthetic arteriovenous (AV) grafts. Methods: Review of our procedural database over a 6 year period revealed 377 procedures involving stent deployment in an AV access circuit. After applying strict inclusion criteria, our study group consisted of 61 stent deployments in 58 patients (median age 58 years, 25 men, 33 women) across the venous anastomosis of an upper extremity AV graft circuit that had never been previously stented. Both patent and thrombosed AV access circuits were retrospectively analyzed. Within the bare metal stent group, 20 of 32 AV grafts were thrombosed at initial presentation compared to 18 of 29 AV grafts in the covered stent group. Results: Thirty-two bare metal stents and 29 covered stents were deployed across the venous anastomosis. The 3, 6, and 12 months primary access patency rates for bare metal stents were not significantly different than for covered stents: 50, 41, and 22 % compared to 59, 52, and 29 %, respectively (p = 0.21). The secondary patency rates were also not significantly different: 78, 78, and 68 % for bare metal stents compared to 76, 69, and 61 % for covered stents, respectively (p = 0.85). However, covered stents demonstrated a higher primary stent patency rate than bare metal stents: 100, 85, and 70 % compared to 75, 67, and 49 % at 3, 6, and 12 months (p < 0.01). Conclusion: The primary and secondary access patency rates after deployment of bare metal versus covered stents at the venous anastomosis were not significantly different. However, bare metal stents developed in-stent stenoses significantly sooner.

  10. Coronary artery stent (image)

    MedlinePlus

    ... with a balloon catheter and expands when the balloon is inflated. The stent is then left there to help keep the artery open. ... with a balloon catheter and expands when the balloon is inflated. The stent is then left there to help keep the artery open.

  11. Palliative Airway Stenting Performed Under Radiological Guidance and Local Anesthesia

    SciTech Connect

    Profili, Stefano; Manca, Antonio; Feo, Claudio F. Padua, Guglielmo; Ortu, Riccardo; Canalis, Giulio C.; Meloni, Giovanni B.

    2007-02-15

    Purpose. To assess the effectiveness of airway stenting performed exclusively under radiological guidance for the palliation of malignant tracheobronchial strictures. Methods. We report our experience in 16 patients with malignant tracheobronchial stricture treated by insertion of 20 Ultraflex self-expandable metal stents performed under fluoroscopic guidance only. Three patients presented dysphagia grade IV due to esophageal malignant infiltration; they therefore underwent combined airway and esophageal stenting. All the procedures were performed under conscious sedation in the radiological room; average procedure time was around 10 min, but the airway impediment never lasted more than 40 sec. Results. We obtained an overall technical success in 16 cases (100%) and clinical success in 14 patients (88%). All prostheses were successfully placed without procedural complications. Rapid clinical improvement with symptom relief and normalization of respiratory function was obtained in 14 cases. Two patients died within 48 hr from causes unrelated to stent placement. Two cases (13%) of migration were observed; they were successfully treated with another stent. Tumor overgrowth developed in other 2 patients (13%); however, no further treatment was possible because of extensive laryngeal infiltration. Conclusions. Tracheobronchial recanalization with self-expandable metal stents is a safe and effective palliative treatment for malignant strictures. Airway stenting performed exclusively under fluoroscopic view was rapid and well tolerated.

  12. Treatment of Carotid Siphon Aneurysms with a Microcell Stent

    PubMed Central

    Leonardi, M.; Dall’Olio, M.; Princiotta, C.; Simonetti, L.

    2008-01-01

    Summary The treatment of giant, large, multiple or wide-necked carotid siphon aneurysms has always represented a challenge for neurosurgeons and neuroradiologists. Very recently the use of stents with tiny holes has been proposed by two companies: Balt Silk Stent in Europe and Pi-peline in America. We have used the Silk stent on a few patients and describe our first case who now has an eleven month follow-up. The carotid siphon presented three converging aneurysms sharing a very large common neck. The Silk stent (Balt Extrusion, Montmorency, France) was deployed through a 4F Balt introducer. The procedure was uneventful and very quick. As soon as the stent was positioned contrast medium stagnation was displayed within the aneur-ysm. The patient’s post-operative course was normal and she was discharged three days later in good health. PMID:20557742

  13. [Problems with Ureteral Stents – a Never-Ending Story].

    PubMed

    Betschart, Patrick; Schmid, Hans-Peter; Abt, Dominik

    2016-03-16

    Temporary drainage of the upper urinary tract by internal ureteral stents is a common procedure to assure renal function and to treat pain caused by ureteral obstruction. Ureteral stents are frequently associated with side effects like urinary symptoms, pain or hematuria resulting in frequent medical consultations. In addition to good patient education, symptomatic drug therapy of stent-associated symptoms is often indicated and sufficient. However, complications like stent dysfunction or significant urinary tract infections have to be kept in mind, as they require further diagnostics and treatment. Therefore, especially general practitioners as a primary point of contact for the patients should be familiar with common ureteral stent-associated problems, their treatment and indications for patient referrals.

  14. Open stent grafting for complex diseases of the thoracic aorta: clinical utility.

    PubMed

    Uchida, Naomichi

    2013-03-01

    Open stent grafting is an alternative treatment for extensive thoracic aortic replacement. However, this procedure is associated with a high incidence of spinal cord injury, which has limited its application. Multiple factors have been suggested to explain the risk of spinal cord injury, including deep delivery of the stent graft, history of operation of the downstream aorta, and postoperative low blood pressure. Cerebrospinal fluid drainage or a hybrid operation in combination with trans-femoral thoracic stent grafting is useful for preventing spinal cord injury. Open stent grafting remains an alternative treatment for atherosclerotic aneurysms with dilatation of the ascending aorta. Open stent grafting for acute aortic dissection is effective for remodeling of the false lumen. The graft diameter for aortic dissection should be 90 % of the total diameter of the aorta, and the distal landing zone should be limited to the T7 vertebral level to prevent new intimal tears or spinal cord injury. Open stent grafting seems a feasible bailout strategy for the treatment of retrograde aortic dissection after TEVAR for type B aortic dissection. Newly designed devices for open stent grafts include the Matsui-Kitamura stent graft or branched open stent graft, which is produced in Japan. The effectiveness of open stent grafting in the treatment of Marfan syndrome remains unclear. A commercially available device for open stent grafting would be desired in Japan. In conclusion, an open stent graft remains an alternative treatment for complex thoracic aortic pathologies.

  15. Extracorporeal shock wave lithotripsy in the primary treatment of encrusted ureteral stents.

    PubMed

    Irkilata, Lokman; Ozgur, Berat Cem; Sancaktutar, Ahmet Ali; Akdeniz, Ekrem; Aydin, Mustafa; Demirel, Huseyin Cihan; Aydin, Hasan Riza; Doluoglu, Omer Gokhan; Resorlu, Berkan; Atilla, Mustafa Kemal

    2015-08-01

    Double pigtail (JJ) ureteral stents, are the most commonly used method of urinary diversion in the ureteral obstructions. Encrustations may occur as a result of prolonged exposure due to forgetting these stents in the body. Removing these materials might be an annoyance. Forty-four patients from three tertiary referral centres with forgotten JJ stents left in them between the years 2007 and 2014 were included in the study. Stents could not be removed by attempted cystoscopy. As an alternative approach, extracorporeal shock wave lithotripsy (ESWL) was the first choice since it is minimally invasive. The results of that treatment are presented along with the relevant demographic data. JJ stenting for urolithiasis was performed in 36 patients, after open surgery in five patients, and for oncological reasons in three patients. ESWL was applied to stents or to any suspicious region adjacent to the stent. In 29 of 44 patients, the stents were easily removed under cystoscopic procedures while in one patient the fragmented residual stent was spontaneously excreted. In eight patients, ureteroscopy was required; in five patients, percutaneous nephrolithotripsy was required; and in one patient, open surgery was required in order to remove stents. ESWL can be considered as a first-line treatment when a forgotten JJ stent is detected despite all precautions after any kind of urological intervention involving insertion of ureteral stents.

  16. Role of metallic stents in benign esophageal stricture

    NASA Astrophysics Data System (ADS)

    Shim, Chan Sup

    2012-10-01

    Simple esophageal strictures, which are focal, straight, and large in diameter, usually require 1 - 3 dilation sessions to relieve symptoms. However, complex strictures, which are long, tortuous, or associated with a severely compromised luminal diameter, are usually more difficult to treat with conventional bougie or balloon dilation techniques, and often have high recurrence rates. Although the permanent placement of self-expandable metal stents (SEMS) has been used to manage refractory benign esophageal strictures, this procedure is associated with additional problems, such as stricture from tissue hyperplasia, stent migration, and fistula formation. Thus, several new types of stents have been developed, including temporary SEMS, self-expandable plastic stents (SEPS), and biodegradable stents. The use of these new products has produced varied results. Temporary SEMS that have been used to relieve benign esophageal conditions have caused granulation tissue at both ends of the stent because of contact between the mucosa and the exposed metal components of the stent, thus hindering stent removal. We examined the tissue response to two new types of SEMS, a flange-type and a straighttype, each coated with a silicone membrane on the outside of the metal mesh. These two SEMS were evaluated individually and compared with a conventional control stent in animal experiments. Although the newly designed stents resulted in reduced tissue hyperplasia, and were thus more easily separated from the esophageal tissue, some degree of tissue hyperplasia did occur. We suggest that newly designed DES (drug-eluting stents) may provide an alternative tool to manage refractory benign esophageal stricture.

  17. Intraarterial Pressure Gradients After Randomized Angioplasty or Stenting of Iliac Artery Lesions

    SciTech Connect

    Tetteroo, Eric; Haaring, Cees; Graaf, Yolanda van der; Schaik, Jan P.J. van; Engelen, A.D. van; Mali, Willem P.T.M.

    1996-11-15

    Purpose: To determine initial technical results of percutaneous transluminal angioplasty (PTA) and stent procedures in the iliac artery, mean intraarterial pressure gradients were recorded before and after each procedure. Methods: We randomly assigned 213 patients with typical intermittent claudication to primary stent placement (n= 107) or primary PTA (n= 106), with subsequent stenting in the case of a residual mean pressure gradient of > 10 mmHg (n= 45). Eligibility criteria included angiographic iliac artery stenosis (> 50% diameter reduction) and/or a peak systolic velocity ratio > 2.5 on duplex examination. Mean intraarterial pressures were simultaneously recorded above and below the lesion, at rest and also during vasodilatation in the case of a resting gradient {<=} 10 mmHg. Results: Pressure gradients in the primary stent group were 14.9 {+-} 10.4 mmHg before and 2.9 {+-} 3.5 mmHg after stenting. Pressure gradients in the primary PTA group were 17.3 {+-} 11.3 mmHg pre-PTA, 4.2 {+-} 5.4 mmHg post-PTA, and 2.5 {+-} 2.8 mmHg after selective stenting. Compared with primary stent placement, PTA plus selective stent placement avoided application of a stent in 63% (86/137) of cases, resulting in a considerable cost saving. Conclusion: Technical results of primary stenting and PTA plus selective stenting are similar in terms of residual pressure gradients.

  18. Differences in Endothelial Injury After Balloon Angioplasty, Insertion of Balloon-Expanded Stents or Release of Self-Expanding Stents: An Electron Microscopic Experimental Study

    SciTech Connect

    Harnek, Jan; Zoucas, Evita; Carlemalm, Erik; Cwikiel, Wojciech

    1999-01-15

    Purpose: To evaluate which of six different commonly available stents inserted into an artery without percutaneous transluminal angioplasty (PTA) causes the least endothelial damage. To compare the degree of endothelial injury after insertion of such a stent with injury caused by PTA. Methods: Twelve healthy pigs were used in the experiments. In the first part of the study six different types of stents were inserted into the common iliac arteries. In the second part of the study self-expanding stents with large spaces between the wires were used. PTA was performed in the contralateral iliac artery. The pigs were killed immediately after the procedure and resected specimens examined after fixation, using scanning electron microscopy. Results: All procedures but two were accomplished successfully. More endothelium was preserved after insertion of self-expanding stents with large spaces between the wires, compared with stents with small spaces and balloon-expanded stents. After insertion of self-expanding stents with large spaces, 50.1% {+-} 16.4% of the endothelium remained intact, compared with only 5.6% {+-} 7.7% after PTA. The difference was statistically significant (p < 0.001). Conclusion: Self-expanding stents with large spaces between the wires, inserted without PTA, cause less damage to the endothelium than other stents and significantly less damage than PTA.

  19. Primary Stenting in Infrarenal Aortic Occlusive Disease

    SciTech Connect

    Nyman, Ulf; Uher, Petr; Lindh, Mats; Lindblad, Bengt; Ivancev, Krasnodar

    2000-03-15

    Purpose: To evaluate the results of primary stenting in aortic occlusive disease.Methods: Thirty patients underwent primary stenting of focal concentric (n = 2) and complex aortic stenoses (n = 19), and aortic or aorto-iliac occlusions (n = 9). Sixteen patients underwent endovascular outflow procedures, three of whom also had distal open surgical reconstructions. Median follow-up was 16 months (range 1-60 months).Results: Guidewire crossing of two aorto-biiliac occlusions failed, resulting in a 93% (28/30) technical success. Major complications included one access hematoma, one myocardial infarction, one death (recurrent thromboembolism) in a patient with widespread malignancy, and one fatal hemorrhage during thrombolysis of distal emboli from a recanalized occluded iliac artery. One patient did not improve his symptoms, resulting in a 1-month clinical success of 83% (25/30). Following restenting the 26 stented survivors changed their clinical limb status to +3 (n = 17) and +2 (n = 9). During follow-up one symptomatic aortic restenosis occurred and was successfully restented.Conclusions: Primary stenting of complex aortic stenoses and short occlusions is an attractive alternative to conventional surgery. Larger studies with longer follow-up and stratification of lesion morphology are warranted to define its role relative to balloon angioplasty. Stenting of aorto-biiliac occlusions is feasible but its role relative to bypass grafting remains to be defined.

  20. Stent intussusception after thromboaspiration through a platinum chrome stent: a particular case of longitudinal stent deformation.

    PubMed

    Mila, Rafael; Vignolo, Gustavo; Trujillo, Pedro

    2015-04-01

    The need to improve stent deliverability has led to the development of thinner and more flexible stents. However, there is concern about decreased longitudinal strength. The number of longitudinal stent deformation reports has dramatically increased. We report a case of stent longitudinal deformation after thromboaspiration through a new generation platinum chrome bare metal stent. Images show an "intussusception effect," an extreme form of the previously described "concertina deformation," as the mechanism of shortening. Since stent technology is constantly evolving, newer devices will probably be designed to have less susceptibility to longitudinal stent deformation.

  1. Inadvertent intracoronary stent extraction 10 months after implantation complicating cutting balloon angioplasty for in-stent restenosis

    SciTech Connect

    Almeda, Francis Q.; Billhardt, Roger A

    2003-09-01

    We report the case of an unusual complication for Cutting Balloon Angioplasty (CBA) during treatment for instent restenosis (ISR), which resulted in inadvertent intracoronary stent extraction 10 months after implantation. In this case report, CBA was utilized to treat an ISR lesion in the distal right coronary artery (RCA). Due to difficulty in withdrawing the cutting balloon into the guide after treatment of the lesion, the entire system (guide, cutting balloon, and guidewire) was removed as a unit from the body. Upon examination of the system, the previously placed stent in the distal RCA was attached to the microtomes of the cutting balloon. Although the precise mechanisms for stent extraction in this case remain speculative, the initial stent used in the distal RCA may have been undersized, and this may have played a major role in this complication. Although there is limited data regarding the optimal strategy to treat the site of the inadvertent stent extraction, we opted to re-stent the area with a properly-sized coronary stent. Following the intervention, there was no residual stenosis with TIMI 3 flow through the vessel. The patient remained asymptomatic and a serum troponin drawn 18 hours after the procedure was normal, and he was discharged the next day. The interventionist must be vigilant about this rare but serious complication when applying CBA in the treatment of ISR, particularly when an undersized or underdeployed stent is suspected.

  2. Endovascular Gene Delivery from a Stent Platform: Gene- Eluting Stents.

    PubMed

    Fishbein, Ilia; Chorny, Michael; Adamo, Richard F; Forbes, Scott P; Corrales, Ricardo A; Alferiev, Ivan S; Levy, Robert J

    A synergistic impact of research in the fields of post-angioplasty restenosis, drug-eluting stents and vascular gene therapy over the past 15 years has shaped the concept of gene-eluting stents. Gene-eluting stents hold promise of overcoming some biological and technical problems inherent to drug-eluting stent technology. As the field of gene-eluting stents matures it becomes evident that all three main design modules of a gene-eluting stent: a therapeutic transgene, a vector and a delivery system are equally important for accomplishing sustained inhibition of neointimal formation in arteries treated with gene delivery stents. This review summarizes prior work on stent-based gene delivery and discusses the main optimization strategies required to move the field of gene-eluting stents to clinical translation.

  3. Endovascular Gene Delivery from a Stent Platform: Gene- Eluting Stents

    PubMed Central

    Fishbein, Ilia; Chorny, Michael; Adamo, Richard F; Forbes, Scott P; Corrales, Ricardo A; Alferiev, Ivan S; Levy, Robert J

    2015-01-01

    A synergistic impact of research in the fields of post-angioplasty restenosis, drug-eluting stents and vascular gene therapy over the past 15 years has shaped the concept of gene-eluting stents. Gene-eluting stents hold promise of overcoming some biological and technical problems inherent to drug-eluting stent technology. As the field of gene-eluting stents matures it becomes evident that all three main design modules of a gene-eluting stent: a therapeutic transgene, a vector and a delivery system are equally important for accomplishing sustained inhibition of neointimal formation in arteries treated with gene delivery stents. This review summarizes prior work on stent-based gene delivery and discusses the main optimization strategies required to move the field of gene-eluting stents to clinical translation. PMID:26225356

  4. Comparison of Open-Cell Stent and Closed-Cell Stent for Treatment of Central Vein Stenosis or Occlusion in Hemodialysis Patients

    PubMed Central

    Kang, Chae Hoon; Yang, Seung Boo; Lee, Woong Hee; Ahn, Jae Hong; Goo, Dong Erk; Han, Nae Jin; Ohm, Joon Young

    2016-01-01

    Background Central vein stenosis or occlusion is a common complication that can lead to significant morbidity and dysfunction of access in the hemodialysis patient. More lesions can develop over time, and preserving access becomes a challenge as life expectancy of the hemodialysis patient increases. Objectives The goal was to compare long-term results and determine the outcomes of open-cell stent versus closed-cell stent for central vein stenosis or occlusion in hemodialysis patients. Patients and Methods From 1997 to 2015, in 401 hemodialysis patients, stent placement for central vein stenosis or occlusion was performed if balloon angioplasty was unsatisfactory, due to elastic recoil or occurrence of restenosis within 3 months. When thrombus was present, primary stenting was performed. A total of 257 open-cell stents and 144 closed-cell stents were used. Angiographic findings including lesion site, central vein stenosis or occlusion, and presence of thrombosis and complication were evaluated. Primary patency rate and mean patency rate of the stent were compared between two stent groups by Kaplan-Meier survival analysis. Results For the open-cell stent group, 159 patients were diagnosed as central vein stenosis and 98 were occlusion. For the closed-cell stent group, 78 were stenosis and 66 were occlusion. There were two complications for central migration and two for procedure-related vein rupture. Open-cell stents and closed-cell stents had mean patency rates of 10.9 ± 0.80 months and 8.5 ± 10.87 months, respectively (P = 0.002). Conclusion The open-cell stent is effective and its performance is higher than that obtained with the closed-cell stent for treating central vein stenosis or occlusion in hemodialysis patients. PMID:27895880

  5. Hybrid procedure combining clip on wrapping and stent placement for ruptured supraclinoid blood blister-like aneurysm of the internal carotid artery.

    PubMed

    Nagasaki, Hirokazu; Narikiyo, Michihisa; Nagayama, Gota; Nagao, Seiya; Tsuboi, Yoshifumi; Kambayashi, Chisaku

    2017-03-01

    Blood blister-like aneurysms of the supraclinoid portion of the internal carotid artery are rare, fragile, and thin-walled lesions with a higher rate of rebleeding. Our case underwent a hybrid procedure combining direct surgical and endovascular approach.

  6. Bare Metal Stenting for Endovascular Exclusion of Aortic Arch Thrombi

    SciTech Connect

    Mahnken, Andreas H.; Hoffman, Andras; Autschbach, Ruediger; Damberg, Anneke L. M.

    2013-08-01

    BackgroundAortic thrombi in the ascending aorta or aortic arch are rare but are associated with a relevant risk of major stroke or distal embolization. Although stent grafting is commonly used as a treatment option in the descending aorta, only a few case reports discuss stenting of the aortic arch for the treatment of a thrombus. The use of bare metal stents in this setting has not yet been described.MethodsWe report two cases of ascending and aortic arch thrombus that were treated by covering the thrombus with an uncovered stent. Both procedures were performed under local anesthesia via a femoral approach. A femoral cutdown was used in one case, and a total percutaneous insertion was possible in the second case.ResultsBoth procedures were successfully performed without any periprocedural complications. Postoperative recovery was uneventful. In both cases, no late complications or recurrent embolization occurred at midterm follow-up, and control CT angiography at 1 respectively 10 months revealed no stent migration, freely perfused supra-aortic branches, and no thrombus recurrence.ConclusionTreating symptomatic thrombi in the ascending aorta or aortic arch with a bare metal stent is feasible. This technique could constitute a minimally invasive alternative to a surgical intervention or complex endovascular therapy with fenestrated or branched stent grafts.

  7. [Advantages of endoscopic stenting for malignant gastrointestinal obstructions].

    PubMed

    Meier, P N; Manns, M P

    2006-03-01

    Self-expanding stents play a major role in the interdisciplinary treatment of gastrointestinal obstructions in patients with local nonresectable tumors, advanced metastasis, and pronounced comorbidity. Reinstenting the passage and sealing esophagotracheal fistulae is very effective as palliative treatment for esophageal tumor complications. In hepatobiliary occlusions, the success rate against cholestasis is also high. Enteral and colorectal stents are gaining favor. Required are an experienced endoscopy team and adequate equipment. The rate of procedural complications is generally low, but rare and severe complications such as perforation must be considered. Further improvements in the materials and construction of stents can be expected.

  8. Dedicated bifurcation stents - Mechanistic, hardware, and technical aspects.

    PubMed

    Mishra, Sundeep

    Percutaneous coronary intervention (PCI) in bifurcation lesions is associated with lower success rate, higher acute complication rates and higher event rates in follow-up. The reason for this higher than usual complication rate relates to the relationship between anatomy, flow, and atheroma distribution in bifurcation lesions. Further, stenting these lesions can be a prolonged procedure and can be technically more demanding. The most common complication is the loss of significant side branch (SB). Main vessel (MV) stenting may enhance the carina displacement and atheroma shift across the SB ostium leading to SB ostium narrowing. Finally, complications, if they occur, are more difficult to manage. Dedicated bifurcation stent has been developed to overcome the number of limitations associated with conventional bifurcation PCI. The main advantage of most dedicated bifurcation stents is to allow the operator to perform the procedure on a bifurcation lesion without the need to rewire the SB.

  9. Influence of stent configuration on cerebral aneurysm fluid dynamics.

    PubMed

    Babiker, M Haithem; Gonzalez, L Fernando; Ryan, Justin; Albuquerque, Felipe; Collins, Daniel; Elvikis, Arius; Frakes, David H

    2012-02-02

    Embolic coiling is the most popular endovascular treatment available for cerebral aneurysms. Nevertheless, the embolic coiling of wide-neck aneurysms is challenging and, in many cases, ineffective. Use of highly porous stents to support coiling of wide-neck aneurysms has become a common procedure in recent years. Several studies have also demonstrated that high porosity stents alone can significantly alter aneurysmal hemodynamics, but differences among different stent configurations have not been fully characterized. As a result, it is usually unclear which stent configuration is optimal for treatment. In this paper, we present a flow study that elucidates the influence of stent configuration on cerebral aneurysm fluid dynamics in an idealized wide-neck basilar tip aneurysm model. Aneurysmal fluid dynamics for three different stent configurations (half-Y, Y and, cross-bar) were first quantified using particle image velocimetry and then compared. Computational fluid dynamics (CFD) simulations were also conducted for selected stent configurations to facilitate validation and provide more detailed characterizations of the fluid dynamics promoted by different stent configurations. In vitro results showed that the Y stent configuration reduced cross-neck flow most significantly, while the cross-bar configuration reduced velocity magnitudes within the aneurysmal sac most significantly. The half-Y configuration led to increased velocity magnitudes within the aneurysmal sac at high parent-vessel flow rates. Experimental results were in strong agreement with CFD simulations. Simulated results indicated that differences in fluid dynamic performance among the different stent configurations can be attributed primarily to protruding struts within the bifurcation region.

  10. Bioabsorbable Stent Quo Vadis: A Case for Nano-Theranostics

    PubMed Central

    Gundogan, Buket; Tan, Aaron; Farhatnia, Yasmin; Alavijeh, Mohammad S.; Cui, Zhanfeng; Seifalian, Alexander M.

    2014-01-01

    Percutaneous coronary intervention (PCI) is one of the most commonly performed invasive medical procedures in medicine today. Since the first coronary balloon angioplasty in 1977, interventional cardiology has seen a wide array of developments in PCI. Bare metal stents (BMS) were soon superseded by the revolutionary drug-eluting stents (DES), which aimed to address the issue of restenosis found with BMS. However, evidence began to mount against DES, with late-stent thrombosis (ST) rates being higher than that of BMS. The bioabsorbable stent may be a promising alternative, providing vessel patency and support for the necessary time required and thereafter degrade into safe non-toxic compounds which are reabsorbed by the body. This temporary presence provides no triggers for ST, which is brought about by non-endothelialized stent struts and drug polymers remaining in vivo for extended periods of time. Likewise, nano-theranostics incorporated into a bioabsorbable stent of the future may provide an incredibly valuable single platform offering both therapeutic and diagnostic capabilities. Such a stent may allow delivery of therapeutic particles to specific sites thus keeping potential toxicity to a minimum, improved ease of tracking delivery in vivo by embedding imaging agents, controlled rate of therapy release and protection of the implanted therapy. Indeed, nanocarriers may allow an increased therapeutic index as well as offer novel post-stent implantation imaging and diagnostic methods for atherosclerosis, restenosis and thrombosis. It is envisioned that a nano-theranostic stent may well form the cornerstone of future stent designs in clinical practice. PMID:24672583

  11. Double stenting for malignant oesophago-respiratory fistula

    PubMed Central

    Kużdżał, Jarosław

    2016-01-01

    Introduction The close anatomical relationship between the oesophagus and bronchial tree results in formation of an oesophago-respiratory fistula in a subset of patients with advanced oesophageal or lung cancer. In those patients stenting of both the oesophagus and tracheobronchial tree is a valid option of palliative treatment. Aim To determine the effectiveness, tolerance, quality of life, safety and survival after double stenting procedures. Material and methods Retrospective analysis of a prospectively collected database was performed, concerning consecutive patients with oesophago-respiratory fistulas treated with double stenting. In all patients the degree of dysphagia, respiratory function before and after the procedure, and quality of life were evaluated. Partially covered oesophageal self-expanding metallic stents (PCESEMS) were used for oesophageal stenting, and silicone Y-type or partially covered self-expanding bronchial and tracheal stents (PCASEMS) were used to restore airway patency. Results Between 2003 and 2015, 31 patients underwent double stenting due to oesophago-respiratory fistulas. Twenty-nine patients were diagnosed with oesophageal squamous cell carcinoma and 2 with bronchial carcinoma. In all patients, improvement in the general condition and quality of life was observed after airway patency restoration. Two patients required mechanical ventilation due to respiratory failure immediately after the procedure. Seven patients with oesophageal fistulas died because of bleeding in the long-term follow-up. Four patients required endoscopic re-intervention. Mean survival time was 67.1 days. Conclusions Double stenting is an effective procedure improving patients’ quality of life. However, life-threatening complications can occur. PMID:27829946

  12. Elastic Deformation Properties of Implanted Endobronchial Wire Stents in Benign and Malignant Bronchial Disease: A Radiographic In Vivo Evaluation

    SciTech Connect

    Hautmann, Hubert; Rieger, Johannes; Huber, Rudolf M.; Pfeifer, Klaus J.

    1999-03-15

    Purpose: To evaluate the long-term mechanical behavior in vivo of expandable endobronchial wire stents, we imaged three different prostheses in the treatment of tracheobronchial disease. Methods: Six patients with bronchial stenoses (three benign, three malignant) underwent insertion of metallic stents. Two self-expandable Wallstents, two balloon-expandable tantalum Strecker stents and two self-expandable nitinol Accuflex stents were used. Measurements of deformation properties were performed during voluntary cough by means of fluoroscopy, at 1 month and 7-10 months after implantation. The procedures were videotaped, their images digitized and the narrowing of stent diameters calculated at intervals of 20 msec. Results: After stent implantation all patients improved with respect to ventilatory function. Radial stent narrowing during cough reached 53% (Wallstent), 59% (tantalum Strecker stent), and 52% (nitinol Accuflex stent) of the relaxed post-implantation diameter. Stent compression was more marked in benign compared with malignant stenoses. In the long term permanent deformation occurred with the tantalum Strecker stents; the other stents were unchanged. Conclusion: Endobronchial wire stents can be helpful in the treatment of major airway collapse and obstructing bronchial lesions. However, evidence of material fatigue as a possible effect of exposure to recurrent mechanical stress on the flexible mesh tube may limit their long-term use. This seems to be predominantly important in benign bronchial collapse.

  13. Migrated biliary stent causing perforation of sigmoid colon and pelvic abscess

    PubMed Central

    Mady, Raafat Fadly; Niaz, Osamah Saad; Assal, Mohamed Moustafa

    2015-01-01

    Endoscopically placed biliary stents are a well-established procedure for the treatment of benign and malignant causes of obstructive jaundice. A plastic stent is usually inserted in patients with obstructive jaundice due to pancreatic cancer as a short-term procedure. Stent migration has been reported as a complication, although in most cases the stent will pass through or remain in the bowel lumen for a period of time. In rare cases, the stent may cause sigmoid perforation and pelvic abscess formation, especially in patients with sigmoid diverticulae or abdominal adhesions due to previous surgery. We present a patient with sigmoid perforation and pelvic abscess due to distal migration of a biliary stent placed to decompress a pancreatic head carcinoma. PMID:25870211

  14. Transradial approach for vertebral artery stenting

    PubMed Central

    Tekieli, Łukasz; Kabłak-Ziembicka, Anna; Paluszek, Piotr; Trystuła, Mariusz; Wójcik-Pędziwiatr, Magdalena; Machnik, Roman; Pieniążek, Piotr

    2015-01-01

    Introductuion Symptomatic severe vertebral artery (VA) stenosis may be treated safely with stent supported angioplasty via femoral access. There is limited clinical data on transradial approach for VA angioplasty in case of peripheral artery disease. Aim To evaluate the safety and efficacy of transradial angioplasty of symptomatic VA stenosis. Material and methods Fifteen patients (age 66 ±7.4 years, 73% men, with VA > 80% stenosis, 11 right-side, all symptomatic from posterior circulation (history of stroke, TIA, or chronic ischaemia symptoms)) with peripheral artery disease (PAD) or unsuccessful attempt via femoral approach were scheduled for VA angioplasty by radial access. Clinical and duplex ultrasound (DUS) follow-up were performed before discharge and 1, 12, and 24 months after VA angioplasty. Results The technical success rate was 100%. In all cases VA angioplasty was performed with the use of single balloon-mounted stent (9 bare metal stents, 6 drug-eluting stents). The mean NASCET VA stenosis was reduced from 85.3% to 5.3% (p < 0.001). No periprocedural death, stroke, myocardial infarction, or transient ischaemic attack occurred. During 24-months follow-up, in 12 of 15 patients chronic ischaemia symptoms release was observed, and no new acute ischaemic neurological symptoms were diagnosed in all patients. One patient died 20 months after intervention from unknown causes. There was one symptomatic borderline VA in-stent stenosis 12 months after angioplasty. Conclusions Transradial VA stenting may be a very effective and safe procedure, and it may constitute an alternative to the femoral approach in patients with symptomatic VA stenosis. PMID:25848368

  15. Stent-Protected Carotid Angioplasty Using a Membrane Stent: A Comparative Cadaver Study

    SciTech Connect

    Mueller-Huelsbeck, Stefan Guehne, Albrecht; Tsokos, Michael; Huesler, Erhard J.; Schaffner, Silvio R.; Paulsen, Friedrich; Hedderich, Juergen; Heller, Martin; Jahnke, Thomas

    2006-08-15

    Purpose. To evaluate the performance of a prototype membrane stent, MembraX, in the prevention of acute and late embolization and to quantify particle embolization during carotid stent placement in human carotid explants in a proof of concept study. Methods. Thirty human carotid cadaveric explants (mild stenoses 0-29%, n = 23; moderate stenoses 30-69%, n = 3; severe stenoses 70-99%, n = 2) that included the common, internal and external carotid arteries were integrated into a pulsatile-flow model. Three groups were formed according to the age of the donors (mean 58.8 years; sample SD 15.99 years) and randomized to three test groups: (I) MembraX, n 9; (II) Xpert bare stent, n = 10; (III) Xpert bare stent with Emboshield protection device, n = 9. Emboli liberated during stent deployment (step A), post-dilatation (step B), and late embolization (step C) were measured in 100 {mu}m effluent filters. When the Emboshield was used, embolus penetration was measured during placement (step D) and retrieval (step E). Late embolization was simulated by compressing the area of the stented vessel five times. Results. Absolute numbers of particles (median; >100 {mu}m) caught in the effluent filter were: (I) MembraX: A = 7, B = 9, C = 3; (II) bare stent: A 6.5, B = 6, C = 4.5; (III) bare stent and Emboshield: A = 7, B = 7, C.=.5, D = 8, E = 10. The data showed no statistical differences according to whether embolic load was analyzed by weight or mean particle size. When summing all procedural steps, the Emboshield caused the greatest load by weight (p 0.011) and the largest number (p = 0.054) of particles. Conclusions. On the basis of these limited data neither a membrane stent nor a protection device showed significant advantages during ex vivo carotid angioplasty. However, the membrane stent seems to have the potential for reducing the emboli responsible for supposed late embolization, whereas more emboli were observed when using a protection device. Further studies are necessary

  16. Coronary Stent Infection Presented as Recurrent Stent Thrombosis

    PubMed Central

    Lai, Chih-Hung; Lin, Yung-Kai; Lee, Wen-Lieng

    2017-01-01

    Percutaneous transluminal coronary angioplasty with metal stent placement has become a well-developed treatment modality for coronary stenotic lesions. Although infection involving implanted stents is rare, it can, however, occur with high morbidity and mortality. We describe herein a case of an inserted coronary stent that was infected and complicated with recurrent stent thrombosis, pseudoaneurysm formation and severe sepsis. Despite repeated intervention and bypass surgery, the patient died from severe sepsis. PMID:28120580

  17. Influence of Vessel Size and Tortuosity on In-stent Restenosis After Stent Implantation in the Vertebral Artery Ostium

    SciTech Connect

    Zhou Zhiming; Yin Qin; Xu Gelin; Yue Xuanye; Zhang Renliang; Zhu Wusheng; Fan Xiaobing; Ma Minmin; Liu Xinfeng

    2011-06-15

    Purpose: Percutaneous transluminal angioplasty and stenting is emerging as an alternative for treating atherosclerotic stenosis in the vertebral artery ostium. However, in-stent restenosis (ISR) still remains a critical issue to be addressed. Little is known about the relationship between anatomic characteristics of the artery and ISR after stent implantation. In this study, we have evaluated influential factors for ISR in a cohort of the patients with stenting in the vertebral artery ostium. Methods: Sixty-one patients with 63 symptomatic lesions in vertebral artery ostium treated with stenting were enrolled onto this study. An average of 12.5 months' clinical and angiographic follow-up results were analyzed retrospectively. The possible influential factors for ISR, including conventional risk factors of cerebrovascular diseases and morphological characteristics of target lesions, were evaluated by univariate and multivariate regression analysis. Results: Technical success was achieved in all 63 interventional procedures. Stenosis was reduced from (mean {+-} standard deviation) 75.5 {+-} 12% before to 1 {+-} 3.6% after the procedure. During the mean 12.5-month angiographic follow-up, ISR was detected in 17 treated vessels (27.0%), with 2 treated arteries (3.2%) resulting in occlusion, and a stent fracture in 1 case (1.6%). Multivariate Cox regression analysis showed that the tortuosity of V1 (hazard ratio 3.54, P = 0.01) and smaller diameter of the stent (hazard ratio 3.8, P = 0.04) were independent predictors of ISR. Conclusions: Angioplasty and stenting for symptomatic stenosis in the vertebral artery ostium stenosis seem to be feasible and effective. Tortuosity and smaller diameter may affect ISR after stent implantation.

  18. The role of endovascular stents in dialysis access maintenance

    PubMed Central

    Kassem, Mohamad El; Alghamdi, Issam; Vazquez-Padron, Roberto I; Asif, Arif; Lenz, Oliver; Sanjar, Tina; Fayad, Fadi; Salman, Loay

    2015-01-01

    Vascular stenosis is most often the culprit behind hemodialysis vascular access dysfunction, and while percutaneous transluminal angioplasty (PTA) remains the gold standard treatment for vascular stenosis, over the past decade the use of stents as a treatment option has been on the rise. Aside from the two FDA approved stent-grafts for the treatment of venous graft anastomosis (VGA) stenosis, use of all other stents in vascular access dysfunction is off-label. KDOQI recommends limiting stent use to specific conditions, such as elastic lesions and recurrent stenosis; otherwise, additional adapted indications are in procedure-related complications, such as grade 2 and 3 hematomas. Published reports have shown the potential use of stents in a variety of conditions leading to vascular access dysfunction; such as VGA stenosis, cephalic arch stenosis, central venous stenosis, dialysis access aneurysmal elimination, Cardiac Implantable Electronic Device induced stenosis, and thrombosed arteriovenous grafts (AVG). While further research is needed for many of these conditions, evidence for recommendations has been clear in some; for instance, we know now that stents should be avoided along cannulations sites and should not be used in eliminating dialysis access aneurysms. In this review article, we evaluate the available evidence for the use of stents in each of the aforementioned conditions leading to hemodialysis vascular access dysfunctions. PMID:26524950

  19. [Results of the upper digestive tract stenting with self-expanding stents].

    PubMed

    Fedorov, A G; Davydova, S V; Klimov, A E; Lebedev, N V

    2013-01-01

    The work is based on the analysis of the palliative treatment of 66 patients with malignant upper digestive tract obstruction who underwent implantation of 75 self-expanding metallic stents in the period of 2003-2012 yy. Early postoperative complications developed in 10 (15.2%) cases. Procedure-related complications were observed in 8 (12.1%) patients, non-specific complications occurred in 2 (3.0%) patients. In-hospital lethality was 4.5% (3 patients). 51 patients were followed until death. Symptomatic relapse of obstruction was observed in 4 cases. Median survival was 97 days. Stenting with self-expanding metal stents was concluded to be an effective and safe method of palliation of malignant upper digestive tract stenosis.

  20. Partially uncovered Cheatham platinum-covered stent to treat complex aortic coarctation associated with aortic wall aneurysm.

    PubMed

    Butera, Gianfranco; Piazza, Luciane

    2015-04-01

    Percutaneous treatment of aortic coarctation is a widely used option. Covered stents have increased the profile of efficacy and safety of this procedure. Here we report on a 32-year-old woman with significant aortic recoarctation associated with aortic wall aneurysm and close proximity of both lesions to the origin of both the subclavian arteries. It was decided to manually and partially uncover the proximal part of the stent to have a hybrid stent that could act as a bare stent at the level of the origin of the subclavian arteries and as a covered stent at the level of the aneurysm.

  1. Will absorbable metal stent technology change our practice?

    PubMed

    Bosiers, M; Deloose, K; Verbist, J; Peeters, P

    2006-08-01

    Peripheral stents aim to support revascularization procedures of intravascular stenoses by mechanically preventing vessel recoil and counteracting pathophysiologic processes of luminal re-narrowing triggered by procedural injury of the vessel wall. Despite improvements in stenting techniques and concomitant medication, repeated intervention due to target lesion re-stenosis is necessary on a significant percentage of patients. The permanent presence of an artificial implant plays a prominent role in the discussion of mechanisms causing in-stent restenosis. Permanent metallic implants pose the risk of a continuous interaction between non-absorbable stent and surrounding tissue, leading to physical irritation, long-term endothelial dysfunction, or chronic inflammatory reactions. In addition, there is a risk of stent fracture due to external mechanical forces. To overcome these shortcomings, technology of stenting has moved towards the development of temporary implants composed of biocompatible materials which mechanically support the vessel during the period of high risk for recoil and then completely degrade in the long-term perspective. This removes a potential trigger for late restenosis.

  2. Expandable polyester silicon-covered stent for malignant esophageal strictures before neoadjuvant chemoradiation: a pilot study.

    PubMed

    Siddiqui, Ali A; Loren, David; Dudnick, Robert; Kowalski, Thomas

    2007-03-01

    Patients with resectable esophageal cancer often require placement of a surgical jejunostomy tube prior to receiving chemoradiation so as to maintain adequate nutrition due to their inability to swallow and eat. This study reports a single institutional experience with the Polyflex self-expanding silicone stent (Riisch; Kernen. Germany) in patients with malignant stenosis receiving chemoradiation prior to esophagectomy. This was a retrospective, nonrandomized study of 6 patients who underwent Polyflex esophageal stent placement across a malignant stricture prior to receiving neoadjuvant chemoradiation. The study assessed procedural success, restoration of oral nutrition, migration, and removal of the Polyflex stent. The outcomes measured were the efficacy of treatment, stent-related complications, and changes in the nutritional status of the patient after stent placement. Stent placement was successful in 5 of 6 patients (83%). Restoration of oral nutrition after stent placement occurred in 5 of 5 patients (100%). Migration of the stent into the stomach occurred in 3 patients (60%) without occurrence of gastric outlet obstruction; there was no proximal migration. Stents were successfully removed endoscopically or at the time of esophagectomy. This early experience suggests that the removable silicone Polyflex stent is an effective alternative to a surgical jejunostomy tube for the management of malignant esophageal stenosis in patients for whom neoadjuvant chemoradiation is planned prior to esophagectomy.

  3. Simulation of bifurcated stent grafts to treat abdominal aortic aneurysms (AAA)

    NASA Astrophysics Data System (ADS)

    Egger, J.; Großkopf, S.; Freisleben, B.

    2007-03-01

    In this paper a method is introduced, to visualize bifurcated stent grafts in CT-Data. The aim is to improve therapy planning for minimal invasive treatment of abdominal aortic aneurysms (AAA). Due to precise measurement of the abdominal aortic aneurysm and exact simulation of the bifurcated stent graft, physicians are supported in choosing a suitable stent prior to an intervention. The presented method can be used to measure the dimensions of the abdominal aortic aneurysm as well as simulate a bifurcated stent graft. Both of these procedures are based on a preceding segmentation and skeletonization of the aortic, right and left iliac. Using these centerlines (aortic, right and left iliac) a bifurcated initial stent is constructed. Through the implementation of an ACM method the initial stent is fit iteratively to the vessel walls - due to the influence of external forces (distance- as well as balloonforce). Following the fitting process, the crucial values for choosing a bifurcated stent graft are measured, e.g. aortic diameter, right and left common iliac diameter, minimum diameter of distal neck. The selected stent is then simulated to the CT-Data - starting with the initial stent. It hereby becomes apparent if the dimensions of the bifurcated stent graft are exact, i.e. the fitting to the arteries was done properly and no ostium was covered.

  4. Chimney stent technique for treatment of severe abdominal aortic atherosclerotic stenosis.

    PubMed

    Ritter, Jens C; Ghosh, Jonathan; Butterfield, John S; McCollum, Charles N; Ashleigh, Raymond

    2011-03-01

    Application of the "chimney" stent technique is described in a case of complex multilevel atherosclerotic disease involving the juxtarenal aorta. A patient with significant comorbidities was unsuitable for major open reconstructive surgery. He was treated with a combined procedure consisting of chimney stent placement in the juxtarenal aorta, iliac "kissing" stent placement, and right-sided common femoral artery (CFA) replacement. This case shows that the chimney stent technique can be a feasible alternative to leaving a safety wire in the renal arteries and observation during primary angioplasty in complex atherosclerotic lesions of the abdominal aorta.

  5. [Stents in iliac vascular changes].

    PubMed

    Gross-Fengels, W; Friedmann, G; Fischbach, R; Erasmi, H; Bulling, B

    1991-01-01

    The results of 79 iliac stent placements in 64 patients are reported. The technical success rate was 96%. The systolic pressure gradient dropped from 44 mmHg before to 2.8 mmHg after stent placement. This differed significantly as compared to a group treated by conventional PTA (gradient 5.8 mmHg). The cumulative patency after 18-20 months was 90%. Angiographic controls up to 19 months after "stenting" demonstrated only one secondary stent occlusion. Iliac stents therefore are a very valuable supplement to classic PTA.

  6. A double J stent misplaced in the inferior vena cava during Boari flap repair

    PubMed Central

    Maheshwari, Pankaj N.; Oswal, Ajay T.; Wagaskar, Vinayak G.

    2016-01-01

    A 30-year-old lady underwent a Boari flap repair for post-hysterectomy mid-ureteric stricture. The upper end of the double J stent inserted during the procedure was misplaced in the supra-renal inferior venal cava. Cystoscopic stent removal could be performed uneventfully, while the stricture was managed by endoureterotomy. PMID:26941499

  7. Nitinol Stent Oversizing in Patients Undergoing Popliteal Artery Revascularization: A Finite Element Study.

    PubMed

    Gökgöl, Can; Diehm, Nicolas; Nezami, Farhad Rikhtegar; Büchler, Philippe

    2015-12-01

    Nitinol stent oversizing is frequently performed in peripheral arteries to ensure a desirable lumen gain. However, the clinical effect of mis-sizing remains controversial. The goal of this study was to provide a better understanding of the structural and hemodynamic effects of Nitinol stent oversizing. Five patient-specific numerical models of non-calcified popliteal arteries were developed to simulate the deployment of Nitinol stents with oversizing ratios ranging from 1.1 to 1.8. In addition to arterial biomechanics, computational fluid dynamics methods were adopted to simulate the physiological blood flow inside the stented arteries. Results showed that stent oversizing led to a limited increase in the acute lumen gain, albeit at the cost of a significant increase in arterial wall stresses. Furthermore, localized areas affected by low Wall Shear Stress increased with higher oversizing ratios. Stents were also negatively impacted by the procedure as their fatigue safety factors gradually decreased with oversizing. These adverse effects to both the artery walls and stents may create circumstances for restenosis. Although the ideal oversizing ratio is stent-specific, this study showed that Nitinol stent oversizing has a very small impact on the immediate lumen gain, which contradicts the clinical motivations of the procedure.

  8. Antiplatelet therapy in patients undergoing coronary stenting

    PubMed Central

    ten Berg, J.M.; van Werkum, J.W.; Heestermans, A.A.C.M.; Jaarsma, W.; Hautvast, R.M.A.; den Heijer, P.; de Boer, M.J.

    2006-01-01

    Background Anticoagulation after coronary stenting is essential to prevent stent thrombosis. Drug-eluting stents, which are the preferred therapy, may be associated with a higher tendency for stent thrombosis. Methods Patients who underwent coronary stent placement and presented with late stent thrombosis are described. Results Eight patients with stent thrombosis are presented. Early discontinuation of the antithrombotic medication is associated with the occurrence of these complications. Conclusion Long-term antithrombotic therapy seems essential to prevent stent thrombosis, especially for patients treated with drug-eluting stents. PMID:25696663

  9. Long-term effects of forgotten biliary stents: a case series and literature review.

    PubMed

    Odabasi, Mehmet; Arslan, Cem; Akbulut, Sami; Abuoglu, Haci Hasan; Ozkan, Erkan; Yildiz, Mehmet Kamil; Eris, Cengiz; Gunay, Emre; Tekesin, Kemal; Muftuoglu, Tolga

    2014-01-01

    There are many studies about the biliary stents, however there is a little information about the long-term stayed forgotten biliary stents except a few case reports. We have reported the results of a number of cases with biliary stents that were forgotten or omitted by the patient and the endoscopist. During February 2010 to May 2013, five patients were referred to the general surgery clinic of Haydarpasa Numune Training and Research Hospital, Istanbul Turkey. Past history and medical documents submitted by the patient did not indicate a replacement of the biliary stent in 3 patients. Two patients knew that they had biliary stents. We also conducted a literature review via the PubMed and Google Scholar databases of English language studies published until March 2014 on forgotten biliary stent. There were 3 men and 2 women ranging in age from 22 to 68 years (mean age 41.6 years). Patients presented with pain in the upper abdomen, jaundice, fever, abnormal liver function tests or dilatation of the biliary tract alone or in combination. Patients' demographic findings are presented in Table 1. A review of three cases reported in the English medical literature also discussed. The mean duration of the patency of the stent is about 12 months. The biliary stenting is performed either with plastic or metal stents, studies recommending their replacement after 3-6 months. Patients with long stayed forgotten biliary stents are inevitably treated with surgical intervention. We recommend for all endoscopic retrograde cholangiopancreatography units provide a stent registry system that the stents placed for various therapeutic procedures are not forgotten both by the patient as well as the physician. There should be a deadline for biliary stents in the registry system for each patient.

  10. Prevention and treatment of symptoms associated with indwelling ureteral stents: A systematic review.

    PubMed

    Betschart, Patrick; Zumstein, Valentin; Piller, Alberto; Schmid, Hans-Peter; Abt, Dominik

    2017-02-25

    Temporary drainage of the upper urinary tract by internal ureteral stents is a routine procedure in endourology. However, it is associated with a clear side-effect profile. Our aim was to evaluate prevention and treatment options of stent-related symptoms. We carried out a systematic review according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines using MEDLINE and SCOPUS, and identified 107 appropriate records. A high number of these studies showed clear methodological limitations. Available data clearly support the use of α1 -blockers in patients suffering from stent-related symptoms. It seems that antimuscarinic monotherapy or combination with α1 -blockers might also play an important role, whereas the use of classical analgesics in the treatment of stent-related symptoms has not been assessed systematically within clinical trials so far. Improvements in stent design and material seem to have the potential to reduce stent-related symptoms. However, so far there is no type of stent with outstanding characteristics and clear evidence suggesting fundamental advantages compared with a standard double pigtail stent. Although stent diameter does not seem to influence patients' comfort, it seems to be beneficial to choose a proper stent-length. Coated and drug-eluting stents, as well as intravesical drug application, seem to be promising concepts to prevent stent-related symptoms, but still have to be considered as experimental approaches. Furthermore, thorough patient education has the potential to reduce the morbidity associated with ureteral stenting. Further research in the field seems to be mandatory.

  11. Coronary covered stents.

    PubMed

    Kilic, Ismail Dogu; Fabris, Enrico; Serdoz, Roberta; Caiazzo, Gianluca; Foin, Nicolas; Abou-Sherif, Sara; Di Mario, Carlo

    2016-11-20

    Covered stents offer an effective bail-out strategy in vessel perforations, are an alternative to surgery for the exclusion of coronary aneurysms, and have a potential role in the treatment of friable embolisation-prone plaques. The aim of this manuscript is to offer an overview of currently available platforms and to report results obtained in prior studies.

  12. Recent developments of imaging modalities of carotid artery stenting.

    PubMed

    Umemoto, Tomoyuki; Pacchioni, Andrea; Nikas, Dimitrios; Reimers, Bernhard

    2017-02-01

    Compared with conventional angiogram-guided procedure, intravascular imaging modalities give us a lot of useful information to make the procedure better. Intravascular imaging modalities give us the information about lesion characters, reference vessel diameter and the interaction between the stent strut and the plaque such as stent strut malapposition or plaque prolapse in real time during the procedure. We can change our strategy according to this information. Intravascular ultrasound (IVUS) is a most common intravascular imaging modality during carotid artery stenting (CAS) in these days. Its advantage is easy to use compared with optical coherence tomograpy (OCT) which has been reported recently in some case reports or case series. However, due to its high resolution, OCT provides more detailed information especially about plaque prolapse and strut malapposition. IVUS and OCT have a potential to improve acute result and reduce the procedural complication by providing the data of lesion character, reference vessel diameter and the interaction of stent strut and vessel wall. Interventionalists who perform CAS procedure should acquire proficiency in imaging modalities during CAS procedure.

  13. Postcatheterization Femoral Arteriovenous Fistulas: Endovascular Treatment with Stent-Grafts

    SciTech Connect

    Onal, Baran Kosar, Sule; Gumus, Terman; Ilgit, Erhan T.; Akpek, Sergin

    2004-09-15

    Purpose: To report our results of stent-graft implantation for the endovascular treatment of postcatheterization femoral arteriovenous fistulas (AVFs) occurring between the deep femoral artery and the femoral vein.Methods: Endovascular treatment of iatrogenic femoral AVFs as a result of arterial puncture for coronary angiography and/or angioplasty was attempted in 10 cases. Balloon-expandable stent-grafts, one for each lesion, were used to repair the fistulas, which were between the deep femoral artery and the femoral vein in all cases. Stent-graft implantation to the deep femoral artery was performed by a contralateral retrograde approach.Results: All stent-grafts were deployed successfully. Complete closure of the fistulas was accomplished immediately in nine of 10 cases. In one case, complete closure could not be obtained but the fact that the complaint subsided was taken to indicate clinical success. In three cases, side branch occlusion of the deep femoral artery occurred. No complications were observed after implantation. Follow-up for 8-31 months (mean 18.5 months) with color Doppler ultrasonography revealed patency of the stented arterial segments without recurrent arteriovenous shunting in those nine patients who had successful immediate closure of their AVFs.Conclusion: Our results with a mean follow-up 18.5 months suggest that stent-graft implantation for the closure of postcatheterization femoral AVFs originating from the deep femoral artery is an effective, minimally invasive alternative procedure.

  14. Design Optimisation of Coronary Artery Stent Systems.

    PubMed

    Bressloff, Neil W; Ragkousis, Giorgos; Curzen, Nick

    2016-02-01

    In recent years, advances in computing power and computational methods have made it possible to perform detailed simulations of the coronary artery stenting procedure and of related virtual tests of performance (including fatigue resistance, corrosion and haemodynamic disturbance). Simultaneously, there has been a growth in systematic computational optimisation studies, largely exploiting the suitability of surrogate modelling methods to time-consuming simulations. To date, systematic optimisation has focussed on stent shape optimisation and has re-affirmed the complexity of the multi-disciplinary, multi-objective problem at hand. Also, surrogate modelling has predominantly involved the method of Kriging. Interestingly, though, optimisation tools, particularly those associated with Kriging, haven't been used as efficiently as they could have been. This has especially been the case with the way that Kriging predictor functions have been updated during the search for optimal designs. Nonetheless, the potential for future, carefully posed, optimisation strategies has been suitably demonstrated, as described in this review.

  15. Acute Cholecystitis Caused by Malignant Cystic Duct Obstruction: Treatment with Metallic Stent Placement

    SciTech Connect

    Miyayama, Shiro Yamashiro, Masashi; Takeda, Taro; Aburano, Hiroyuki; Komatsu, Tetsuya; Sanada, Taku; Kosaka, Shotaro; Toya, Daisyu; Matsui, Osamu

    2008-07-15

    We report the successful management of acute cholecystitis using cystic duct stent placement in 3 patients with inoperable malignant cystic duct obstruction (2 cholangiocarcinoma and 1 pancreatic carcinoma). All patients underwent stent placement in the bile duct, using an uncovered stent in 2 and a covered stent in 1, to relieve jaundice occurring 8-184 days (mean 120 days) before the development of acute cholecystitis. The occluded cystic duct was traversed by a microcatheter and a stent was implanted 4-17 days (mean 12 days) after cholecystostomy. Acute cholecystitis was improved after the procedure in all patients. Two patients died 3 and 10 months later, while 1 has survived without cholecystitis for 22 months after the procedure to date.

  16. Direct Primary or Secondary Percutaneous Ureteral Stenting: What Is the Most Compliant Option in Patients with Malignant Ureteral Obstructions?

    SciTech Connect

    Carrafiello, Gianpaolo Lagana, Domenico; Lumia, Domenico; Giorgianni, Andrea; Mangini, Monica; Santoro, Domenico; Cuffari, Salvatore; Marconi, Alberto; Novario, Raffaele; Fugazzola, Carlo

    2007-09-15

    The objective of this study was to analyze three ureteral stenting techniques in patients with malignant ureteral obstructions, considering the indications, techniques, procedural costs, and complications. In the period between June 2003 and June 2006, 45 patients with bilateral malignant ureteral obstructions were evaluated (24 males, 21 females; average age, 68.3; range, 42-87). All of the patients were treated with ureteral stenting: 30 (mild strictures) with direct stenting (insertion of the stent without predilation), 30 (moderate/severe strictures) with primary stenting (insertion of the stent after predilation in a one-stage procedure), and 30 (mild/moderate/severe strictures with infection) with secondary stenting (insertion of the stent after predilation and 2-3 days after nephrostomy). The incidence of complications and procedural costs were compared by a statistical analysis. The primary technical success rate was 98.89%. We did not observe any major complications. The minor complication rate was 11.1%. The incidence of complications for the various techniques was not statistically significantly. The statistical analysis of costs demonstrated that the average cost of secondary stenting ( Euro 637; SD, Euro 115) was significantly higher than that of procedures which involved direct or primary stenting ( Euro 560; SD, Euro 108). We conclude that one-step stenting (direct or primary) is a valid option to secondary stenting in correctly selected patients, owing to the fact that when the procedure is performed by expert interventional radiologists there are high technical success rates, low complication rates, and a reduction in costs.

  17. Mechanical Characteristics of Composite Knitted Stents

    SciTech Connect

    Tokuda, Takanori Shomura, Yuzo; Tanigawa, Noboru; Kariya, Shuji; Komemushi, Atsushi; Kojima, Hiroyuki; Sawada, Satoshi

    2009-09-15

    We used metal wires and fibers to fabricate a composite knitted stent and then compare the mechanical characteristics of this stent with those of a pure metallic stent of the same construction in order to develop a stent that offers a comparable degree of expandability as metallic stents but can be used for highly curved lesions that cannot be treated using metallic stents. We fabricated two types of composite knitted stent (N-Z stents), using nitinol wire with a diameter of 0.12 mm and polypara-phenylene-benzobisoxazole (PBO) multifilament fiber (Zyron AS; Toyobo, Osaka, Japan). Stents were knitted into a cylindrical shape using the same textile pattern as a Strecker stent. Two loop lengths (L) of nitinol wire were used in the N-Z stents: L = 1.84 mm (N-Z stent L = 1.84) and L = 2.08 mm (N-Z stent L = 2.08). For the sake of comparison, we fabricated a metallic stent of nitinol using the same textile pattern (N-N stent L = 1.92). We applied a radial compression force diametrically to each stent and applied a bending force diametrically at the free end of a stent with one end fixed in order to evaluate the relationship between stent elasticity and load values. In addition, we macroscopically evaluated the generation of kinks when the stent was bent 180{sup o}. The radial compressive force when the stent diameter was reduced by 53% was 6.44 N in the case of N-Z stent L = 1.84, 6.14 N in the case of N-Z stent L = 2.08, and 4.96 N in the case of N-N stent L = 1.92 mm. The composite stent had a radial compressive force higher than that of a metallic stent. The restoring force to longitudinal direction at a 90{sup o} bending angle was 0.005 N for N-Z stent L = 1.84, 0.003 N for N-Z stent L = 2.08, and 0.034 N for N-N stent L = 1.92. The restoring force of the composite stent was significantly lower. Finally, the composite stent generated no definitive kinks at a bending angle of 180{sup o}, regardless of loop length. However, the N-N stent clearly produced kinks, causing

  18. Antireflux Metal Stent as a First-Line Metal Stent for Distal Malignant Biliary Obstruction: A Pilot Study

    PubMed Central

    Hamada, Tsuyoshi; Isayama, Hiroyuki; Nakai, Yousuke; Togawa, Osamu; Takahara, Naminatsu; Uchino, Rie; Mizuno, Suguru; Mohri, Dai; Yagioka, Hiroshi; Kogure, Hirofumi; Matsubara, Saburo; Yamamoto, Natsuyo; Ito, Yukiko; Tada, Minoru; Koike, Kazuhiko

    2017-01-01

    Background/Aims In distal malignant biliary obstruction, an antireflux metal stent (ARMS) with a funnel-shaped valve is effective as a reintervention for metal stent occlusion caused by reflux. This study sought to evaluate the feasibility of this ARMS as a first-line metal stent. Methods Patients with nonresectable distal malignant biliary obstruction were identified between April and December 2014 at three Japanese tertiary centers. We retrospectively evaluated recurrent biliary obstruction and adverse events after ARMS placement. Results In total, 20 consecutive patients were included. The most common cause of biliary obstruction was pancreatic cancer (75%). Overall, recurrent biliary obstruction was observed in seven patients (35%), with a median time to recurrent biliary obstruction of 246 days (range, 11 to 246 days). Stent occlusion occurred in five patients (25%), the causes of which were sludge and food impaction in three and two patients, respectively. Stent migration occurred in two patients (10%). The rate of adverse events associated with ARMS was 25%: pancreatitis occurred in three patients, cholecystitis in one and liver abscess in one. No patients experienced non-occlusion cholangitis. Conclusions The ARMS as a first-line biliary drainage procedure was feasible. Because the ARMS did not fully prevent stent dysfunction due to reflux, further investigation is warranted. PMID:27282268

  19. Delayed complications after flow-diverter stenting: reactive in-stent stenosis and creeping stents.

    PubMed

    Cohen, José E; Gomori, John Moshe; Moscovici, Samuel; Leker, Ronen R; Itshayek, Eyal

    2014-07-01

    We assessed the frequency and severity of changes in stent configuration and location after the treatment of intracranial aneurysms, and patterns of in-stent stenosis. We retrospectively reviewed data for consecutive aneurysm patients managed with endovascular implantation of flow-diverter stents (Silk Flow Diverter [Balt Extrusion, Montmorency, France] and Pipeline Embolization Device [ev3/Coviden, Minneapolis, MN, USA]) from October 2011 to July 2012. Routine 2, 6, 9-12, and 16-20 month follow-up angiograms were compared, with a focus on changes in stent configuration and location from immediately after deployment to angiographic follow-up, and the incidence and development of in-stent stenosis. Thirty-four patients with 42 aneurysms met inclusion criteria. The Silk device was implanted in 16 patients (47%, single device in 15), the Pipeline device in 18 (53%, single device in 16). On first follow-up angiography, in-stent stenosis was observed in 38% of Silk devices and 39% of Pipeline devices. In-stent stenosis was asymptomatic in 12 of 13 patients. One woman presented with transient ischemic attacks and required stent angioplasty due to end tapering and mild, diffuse in-stent stenosis. Configuration and location changes, including stent creeping and end tapering were seen in 2/16 patients (13%) with Silk devices, and 0/18 patients with Pipeline devices. We describe stent creeping and end tapering as unusual findings with the potential for delayed clinical complications. In-stent stenosis, with a unique behavior, is a frequent angiographic finding observed after flow-diverter stent implant. The stenosis is usually asymptomatic; however, close clinical and angiographic monitoring is mandatory for individualized management.

  20. Wave reflection at a stent.

    PubMed

    Crespo, Antonio; García, Javier; Manuel, Fernando

    2013-01-01

    A simple analytical expression has been derived to calculate the characteristics of a wave that reflects at a stent implanted in a uniform vessel. The stent is characterized by its length and the wave velocity in the stented region. The reflected wave is proportional to the time derivative of the incident wave. The reflection coefficient is a small quantity of the order of the length of the stent divided by the wavelength of the unstented vessel. The results obtained coincide with those obtained numerically by Charonko et al. The main simplifications used are small amplitude of the waves so that equations can be linearized and that the length of the stent is small enough so that the values of the wave functions are nearly uniform along the stent. Both assumptions hold in typical situations.

  1. Common femoral endovenectomy in conjunction with iliac vein stenting to improve venous inflow in severe post-thrombotic obstruction.

    PubMed

    Verma, Himanshu; Tripathi, Ramesh K

    2017-01-01

    Post-thrombotic syndrome secondary to iliofemoral deep venous thrombosis is a significant contributor to advanced chronic venous insufficiency. Iliac vein stenting is a standard procedure to treat iliocaval obstruction. In cases with obstruction extending across the groin, venous inflow for an iliac vein stent may be poor and compromise results of iliac vein stenting. Treatment options include extension of stents across the inguinal ligament that may have limitations in improving inflow only from only one vessel. Endovenectomy in this scenario becomes an attractive option with or without iliac vein stenting to provide outflow to the profunda vein, which otherwise is "axially transformed" in chronic iliofemoral deep venous thrombosis. We describe a technique of endovenectomy in combination with iliac vein stenting to establish a patent outflow tract for profunda and femoral veins. Accompanying also is a video demonstration of endovenectomy that will help viewers understand more technical aspects of the procedure.

  2. [Carotid stenosis: the technic for PTA and stent implantation].

    PubMed

    Thurnher, S

    2000-09-01

    Percutaneous transluminal angioplasty and stenting of carotid artery stenosis represents an innovative experimental modality which has been increasingly employed in high-risk patients. Currently, results from prospective randomized trials are not available; thus, guidelines with regard to indications and technique are preliminary. Numerous technical innovations to avoid associated complications have evolved in neurointerventional procedures. Dedicated guiding catheters and stents using a transfemoral approach have been introduced for treatment of carotid artery disease. Low-profile stent delivery systems may decrease risk of releasing embolic load when crossing high-grade stenosis or kinking of the vessel. The introduction of a cerebral protection with the use of temporary occlusion balloons or filter systems has resulted in a reduction of procedure-related neurological complications, and is strongly recommended by leading experts in the field.

  3. Percutaneous intraductal radiofrequency ablation for treatment of biliary stent occlusion: A preliminary result

    PubMed Central

    Xia, Ning; Gong, Ju; Lu, Jian; Chen, Zhi-Jin; Zhang, Li-Yun; Wang, Zhong-Min

    2017-01-01

    AIM To assess the feasibility and effectiveness of a novel application of percutaneous intraductal radiofrequency (RF) for the treatment of biliary stent obstruction. METHODS We specifically report a retrospective study presenting the results of percutaneous intraductal RF in patients with biliary stent occlusion. A total of 43 cases involving biliary stent obstruction were treated by placing an EndoHPB catheter and percutaneous intraductal RF was performed to clean stents. The stent patency was evaluated by cholangiography and follow-up by contrast enhanced computed tomography or ultrasound after the removal of the drainage catheter. RESULTS Following the procedures, of the 43 patients, 40 survived and 3 died with a median survival of 80.5 (range: 30-243) d. One patient was lost to follow-up. One patient had the stent patent at the time of last follow-up. Two patients with stent blockage at 35 d and 44 d after procedure underwent percutaneous transhepatic drain insertion only. The levels of bilirubin before and after the procedure were 128 ± 65 μmol/L and 63 ± 29 μmol/L, respectively. There were no related complications (haemorrhage, bile duct perforation, bile leak or pancreatitis) and all patients’ stent patency was confirmed by cholangiography after the procedure, with a median patency time of 107 (range: 12-180) d. CONCLUSION This preliminary clinical study demonstrated that percutaneous intraductal RF is safe and effective for the treatment of biliary stent obstruction, increasing the duration of stent patency, although randomized controlled trials are needed to confirm the effectiveness of this approach. PMID:28348491

  4. Image-based dosimetry of an implanted radioactive stent using intravascular ultrasound

    NASA Astrophysics Data System (ADS)

    Peterson, Stephen W.

    Angioplasty has become an increasingly popular and effective treatment for heart disease. Unfortunately, restenosis, a cellular and biological reaction to the procedure, has hindered its effectiveness. Two of the most successful methods of inhibiting restenosis are radiation and stents. The combination of these two components, radioactive stents, is not as common as some of the other methods, yet still has potential of slowing restenosis. Investigation into source characteristics and artery wall radiobiology may illuminate some possible solutions to the problems of restenosis. This work has developed a calculational method to look at in-vivo images of implanted stents and determine the dose to the artery walls in order to test different source characteristics. The images are Intravascular Ultrasound (IVUS) cross-sectional slices of the stent and the artery. From these images, it is possible to determine the implanted stent structure. The pieces of the stent are identified in the images and modeled in a Monte Carlo simulation, using MCNP4c3. The simulation results were combined with the images to give three-dimensional absolute dose contours of the stent. The absolute dose values were verified using radiochromic film and 198Au-plated stents. This work was able to successfully verify the dose results and create a three-dimensional dose map of the implanted stent.

  5. Primary Stenting for Complex Atherosclerotic Plaques in Aortic and Iliac Stenoses

    SciTech Connect

    Onal, Baran; Ilgit, Erhan T.; Yuecel, Cem; Ozbek, Erdal; Vural, Murat; Akpek, Sergin

    1998-09-15

    Purpose: To evaluate the efficacy of primary stenting for complex atherosclerotic plaques in aortic and iliac stenoses that are not amenable to balloon angioplasty alone. Methods: Nineteen patients with complex atherosclerotic plaques were treated with a Palmaz stent (n= 19), Wallstent (n= 1), Strecker stent (n= 1), or Memotherm stent (n= 1). A total of 22 stenoses presenting with complex plaque morphology including ulcerated plaques, ulcerated plaques with focal aneurysms, plaques with heavy calcification, severely eccentric plaques, plaques with overhanging edge, and plaques with spontaneous dissection were stented. The lesions were in the aorta (n= 1), common iliac artery (n= 19), or external iliac artery (n= 2). Results: Immediate angiography after stent placement revealed restoration of patency of the stented segment. Focal aneurysms and ulcerated areas were occluded in the follow-up angiographies obtained 4-12 weeks after the procedure. In one case with poor distal runoff and multiple complex lesions of the iliac artery, subacute occlusion occurred. Clinical and angiographic follow-up (3-46 months) revealed patency of all other stented segments. Conclusion: Primary stenting is an effective and reliable approach for complex plaques in stenoses. Patency of the arterial segment with a smooth lumen can be created without the risk of acute complications such as distal embolization, dissection, or occlusion.

  6. Increased artery wall stress post-stenting leads to greater intimal thickening.

    PubMed

    Timmins, Lucas H; Miller, Matthew W; Clubb, Fred J; Moore, James E

    2011-06-01

    Since the first human procedure in the late 1980s, vascular stent implantation has been accepted as a standard form of treatment of atherosclerosis. Despite their tremendous success, these medical devices are not without their problems, as excessive neointimal hyperplasia can result in the formation of a new blockage (restenosis). Clinical data suggest that stent design is a key factor in the development of restenosis. Additionally, computational studies indicate that the biomechanical environment is strongly dependent on the geometrical configuration of the stent, and, therefore, possibly involved in the development of restenosis. We hypothesize that stents that induce higher stresses on the artery wall lead to a more aggressive pathobiologic response, as determined by the amount of neointimal hyperplasia. The aim of this investigation was to examine the role of solid biomechanics in the development of restenosis. A combination of computational modeling techniques and in vivo analysis were employed to investigate the pathobiologic response to two stent designs that impose greater or lesser levels of stress on the artery wall. Stent designs were implanted in a porcine model (pigs) for approximately 28 days and novel integrative pathology techniques (quantitative micro-computed tomography, histomorphometry) were utilized to quantify the pathobiologic response. Concomitantly, computational methods were used to quantify the mechanical loads that the two stents place on the artery. Results reveal a strong correlation between the computed stress values induced on the artery wall and the pathobiologic response; the stent that subjected the artery to the higher stresses had significantly more neointimal thickening at stent struts (high-stress stent: 0.197±0.020 mm vs low-stress stent: 0.071±0.016 mm). Therefore, we conclude that the pathobiologic differences are a direct result of the solid biomechanical environment, confirming the hypothesis that stents that impose

  7. The Use of Solitaire AB Stents in Coil Embolization of Wide-Necked Cerebral Aneurysms

    PubMed Central

    Han, Xin-Wei; Yan, Lei; Ma, Ji; Guo, Dong; Zhu, Hong-Can; Wang, Shu-Kai; He, Yuan-Hong; Chen, Wen-Wu; Wei, Li-Ping; Wang, Ming-Ke; Song, Tai-Min

    2015-01-01

    Background The Solitaire AB stent is one of many assistant stents used for treating wide-necked cerebral aneurysm, and has been used since 2003. However, large sample studies on its safety and effectiveness are lacking. The objective of this study was to evaluate the effectiveness and safety of the Solitaire AB stent in the coil embolization of wide-necked cerebral aneurysms. Methods Retrospective review of the clinical and image data of 116 patients with wide-necked cerebral aneurysms who had been enrolled at six interventional neuroradiology centers from February 2010 to February 2014 and had been treated by coil embolization; in total, 120 Solitaire AB stents were used. The degree of aneurysm occlusion was examined using digital subtraction angiography (DSA) immediately after the procedure and during follow-up, and was graded using the modified Raymond classification. We also observed complications to evaluate the safety and effectiveness of this therapy. Results The 120 Solitaire AB stents (4 mm × 15 mm, four stents; 4 mm × 20 mm, 16 stents; 6 mm × 20 mm, 36 stents; 6 mm × 30 mm, 64 stents) were inserted to treat 120 wide-necked cerebral aneurysms. All stents were inserted successfully. DSA immediately post-surgery revealed 55 cases of complete occlusion, 59 cases of neck remnant, and six cases of aneurysm remnant. Perioperatively, there were four cases of hemorrhage and four cases of stent thrombosis. The follow-up spanned 3–37 months; of 92 patients examined by DSA at the 6-month follow up, 12 had disease recurrence. Conclusions The Solitaire AB stent is effective with a good technical success rate and short-term effect for assisting coil embolization of wide-necked cerebral aneurysms. PMID:26426804

  8. Stent-assisted coiling strategies for the treatment of wide-necked basilar artery bifurcation aneurysms.

    PubMed

    Zhang, Jian-Zhong; Yang, Peng-Fei; Huang, Qing-Hai; Xu, Yi; Hong, Bo; Zhao, Wen-Yuan; Liu, Jian-Min

    2014-06-01

    Stent-assisted coiling is now the preferred treatment option for wide-necked basilar artery bifurcation aneurysms (BABA). However, the optimal choice of specific treatment strategies is still not well documented. In this paper, based on the "two-neck" theory of BABA, we classified the stent-assisted coiling treatment of BABA into three types: unilateral stent-assisted coiling, unilateral stent plus contralateral microcatheter or microwire-assisted coiling, and bilateral stent-assisted coiling. We assessed the feasibility and effectiveness of different stent-assisted coiling strategies for the treatment of BABA. Twenty-three BABA patients treated with stent-assisted coiling between May 2003 and September 2012 were included. Of the 23 aneurysms, 16 were treated with unilateral stent-assisted coiling, two were treated with unilateral stent and microcatheter or microwire-assisted coiling, and five were treated with bilateral stent-assisted coiling. All 23 BABA were successfully embolized, with a technical success rate of 100%. According to the Raymond classification, the immediate procedural outcome was grade I in nine patients, grade II (neck residue) in four patients and grade III (body filling) in 10 patients. The rate of procedure-related complications was 4.3% (1/23), where intra-operative hemorrhage occurred during coiling due to rupture of the aneurysm. Of the 23 patients, 16 (69.6%) had angiographic follow-up. The mean follow-up duration was 13.5 months (range 1-46 months). Angiographic follow-up showed complete occlusion in 10 patients (62.5%), improvement in two patients (12.5%), stability in three patients (18.7%), and recanalization in one patient (6.25%). The various stent-assisted coiling strategies available at present are feasible and effective for the treatment of wide-necked BABA.

  9. Carotid stenting using tapered and nontapered stents: associated neurological complications and restenosis rates.

    PubMed

    Brown, Katherine E; Usman, Asad; Kibbe, Melina R; Morasch, Mark D; Matsumura, Jon S; Pearce, William H; Amaranto, Daniel J; Eskandari, Mark K

    2009-01-01

    Self-expanding stent design systems for carotid artery stenting (CAS) have morphed from nontapered (NTS) to tapered (TS); however, the impact of this change is unknown. We reviewed the outcomes of CAS with these two broad categories of stents in a single-center retrospective review of 308 CAS procedures from May 2001 to July 2007. Nitinol self-expanding TS or NTS coupled with cerebral embolic protection devices were used to treat extracranial carotid occlusive disease. Data analysis included demographics, procedural records, duplex exams, and conventional arteriography. Mean follow-up was 18 months (range 1-69). Restenosis was defined as >or=80% in-stent carotid artery stenosis by angiography. The mean age of the entire cohort was 71.3 years (75% men, 25% women). Of the 308 cases, 233 were de novo lesions and 75 had a prior ipsilateral carotid endarterectomy (n = 44) or external beam radiation exposure (n = 31). Preprocedure neurological symptoms were present in 30% of patients. TS were used in 156 procedures and NTS in 152 procedures. The 30-day ipsilateral stroke and death rates were 1.3% and 0.3%, respectively. An additional three (1.0%) posterior circulation strokes occurred. There was no statistically significant difference in the 30-day total stroke rates between TS (3.2%, n = 5) and NTS (1.3%, n = 2) (p = 0.5). At midterm follow-up, restenosis or asymptomatic occlusion was detected in eight cases (2.6%). All occurred in arteries treated with NTS, and this was statistically different when compared to arteries treated with TS (p = 0.03). Furthermore, a post-hoc subgroup analysis revealed significant correlation (chi(2) = 0.02) for restenosis in "hostile necks" when separated by TS vs. NTS. Early CAS outcomes between TS and NTS are comparable. In contrast, self-expanding nitinol TS may have a lower incidence of significant restenosis or asymptomatic occlusion when compared to NTS.

  10. Management of cervical esophageal strictures with self-expanding metalic stents.

    PubMed

    Cindoruk, Mehmet; Karakan, Tarkan

    2006-12-01

    Esophageal strictures due to malignant diseases are treated with self-expanding metalicic stents. However, experience is limited with these metalic stents in the cervical esophagus. Due to technical difficulties and procedure-related complications, the cervical esophagus has been assigned as a risky area for stenting procedures. Another encountered problem is patient discomfort after the procedure. In this case report, we present three patients with cervical esophageal strictures who were successfully treated with self-expandable metalic stents. Two of these patients had inoperable esophageal carcinoma and the third had benign stenosis due to radiotherapy of larynx carcinoma. The two patients with malignant disease survived four and six months, respectively, after the procedure. The last patient with benign disease is still alive and has been without dysphagia symptom for six months.

  11. Palliative Treatment of Malignant Colorectal Strictures with Metallic Stents

    SciTech Connect

    Paul Diaz, Laura; Pinto Pabon, Isabel; Fernandez Lobato, Rosa; Montes Lopez, Carmen

    1999-01-15

    Purpose: To assess the effectiveness and safety of self-expanding metallic stents as a primary palliative treatment for inoperable malignant colorectal strictures. Methods: Under radiological guidance 20 self-expanding metallic Wallstents were implanted in 16 consecutive patients with colorectal stenoses caused by malignant neoplasms, when surgical treatment of the condition had been ruled out. The patients were followed up clinically for 1-44 months, until death or termination of this study. Results: The stents were successfully implanted in all cases and resolved the clinical obstruction in all the patients except one, who underwent subsequent colostomy. During follow-up of the remaining 15 patients, clinical complications arising from the procedure were pain (two patients), minor rectal bleeding (one patient), and severe rectal bleeding (one patient) (26%). There were three cases of stent migration and three cases of stent occlusion, and reintervention by us was necessary in 20% of cases (3/15). The mean life span following the procedure was 130 days, and none of the patients exhibited clinical symptoms of obstruction at the time of death (12 patients) or termination of the study (3 patients). Conclusion: Deployment of metallic stents under radiologic guidance is an effective alternative as a primary palliative measure in malignant colorectal obstruction, though the possible clinical complications and need for repeat intervention during follow-up should be taken into account.

  12. Nasal packing and stenting

    PubMed Central

    Weber, Rainer K.

    2011-01-01

    Nasal packs are indispensable in ENT practice. This study reviews current indications, effectiveness and risks of nasal packs and stents. In endoscopic surgery, nasal packs should always have smooth surfaces to minimize mucosal damage, improve wound healing and increase patient comfort. Functional endoscopic endonasal sinus surgery allows the use of modern nasal packs, since pressure is no longer required. So called hemostatic/resorbable materials are a first step in this direction. However, they may lead to adhesions and foreign body reactions in mucosal membranes. Simple occlusion is an effective method for creating a moist milieu for improved wound healing and avoiding dryness. Stenting of the frontal sinus is recommended if surgery fails to produce a wide, physiologically shaped drainage path that is sufficiently covered by intact tissue. PMID:22073095

  13. Leo Stent for Endovascular Treatment of Broad-Necked and Fusiform Intracranial Aneurysms

    PubMed Central

    Juszkat, R.; Nowak, S.; Smól, S.; Kociemba, W.; Blok, T.; Zarzecka, A.

    2007-01-01

    Summary The advent of intracranial stents has widened the indications for endovascular treatment of broad-necked and fusiform aneurysms. Leo stent is a self-expandable, nitinol, braided stent dedicated to intracranial vessels. The aim of this study is to present our experience in endovascular treatment of broad-necked and fusiform intracranial aneurysms using self-expanding, nitinol Leo stents. Between February 2004 and November 2006, 25 broad-necked and three fusiform aneurysms in 28 patients were treated using Leo stents in our centre. There were 18 patients who experienced acute subarachnoid haemorrhage due to aneurysm rupture, two patients who experienced SAH at least 12 months ago and in eight patients aneurysms were found incidentally. Aneurysms were located as follows: internal carotid artery15, basilar artery5, basilar tip3, posterior inferior cerebral artery2, M1/M2 segment1, A2 segment1 and vertebral artery1. There were no difficulties with stent deployment and delivery. All patients after acute SAH (n=18) underwent stent implantation and coil embolization in one procedure. The remaining patients underwent coil embolization in a staged procedure. Immediate aneurysm occlusion of more than 95% was achieved in all patients who underwent stent placement and coil embolization in one procedure. There were three thromboembolic complications encountered in patients in an acute setting of SAH, preloaded only on acetylsalicylic acid. Use of abciximab led to patency within the stent and parent vessel. However, one of these patients presented rebleeding from the aneurysm during administration of abciximab and died. Application of Leo stents in cases of broadnecked and fusiform intracranial aneurysms is safe and effective with a low complication rate. PMID:20566117

  14. “Bendy” stents help negotiate hairpin intracardiac curves

    PubMed Central

    Grech, V; DeGiovanni, JV

    2015-01-01

    Simple transposition of the great arteries (TGA) occurs in 0.2 per 1000 live births. The condition is surgically repaired in the neonatal period by the arterial switch procedure (ASO) sometimes preceded by an atrial septostomy. The ASO involves transecting the great arteries and relocating them to the appropriate ventriculo-arterial (VA) connection with attachment of the disconnected coronary arteries to the aorta. In the process, the attachment of the pulmonary artery to the right ventricle involves the Le Compte manoeuvre and to achieve this the pulmonary arteries must be fully mobilised and sometimes the main pulmonary artery may require patch augmentation as well. Nevertheless, pulmonary artery stenosis (PAS) is one of the potential problems with the ASO. However, with improved surgical techniques, this has dropped from around 15% in the 1980s to less than 3%. Apart from surgical revision when PAS occurs, there are interventional options which include angioplasty and/or stent insertion. The latter is preferred in small children and works well in around 60% but may require repeat procedures. In older patients or when angioplasty fails, stent insertion can be considered. These procedures may involve negotiating tight bends in order to reach the site of stenosis. The passage of non-premounted stents may be problematic in such situations, especially with longer stents and tighter bends as they tend to slip off balloon. We describe several techniques that may facilitate such interventions, and these were utilised in an adolescent patient who had had ASO for TGA in the neonatal period. These included manually giving the mounted stent a slight bend in order to help the balloon-stent assembly negotiate hairpin bends. PMID:26865851

  15. Mechanical thrombectomy using Rotarex system and stent-in-stent placement for treatment of distal femoral artery occlusion secondary to stent fracture – a case report and literature review

    PubMed Central

    Dys, Krzysztof; Drelichowska-Durawa, Justyna; Dołega-Kozierowski, Bartosz; Lis, Michał; Sokratous, Kyriakos; Iwanowski, Wojciech; Drelichowski, Stanisław; Witkiewicz, Wojciech

    2013-01-01

    Summary Background: Treatment of peripheral arterial diseases may be distinguished into conservative and interventional management; the latter is divided into surgical and endovascular procedures. Management of peripheral artery stenosis and occlusion with vascular stents is associated with the risk of late complications such as restenosis, stent fracture or dislocation. Case Report: A 62-year-old woman with generalized atherosclerosis, particularly extensive in lower limb arteries, was admitted to the Department of Angiology 11 months after having an endovascular procedure performed due to critical ischemia of left lower limb. Because of stent occlusion, a decision to perform angiographic examination of lower limb arteries was made. Examination revealed occlusion of the superficial femoral artery along its entire length, including previously implanted stents. Distal stent was fractured with slight dislocation of the proximal segment. A decision was made to perform mechanical thrombectomy using a Rotarex system followed by a stent-in-stent placement procedure. Follow-up angiography and ultrasound scan performed 24 hours after the procedure revealed a patent vessel with satisfactory blood flow. Discussion: Nowadays, imaging diagnostics of peripheral artery stenosis involves non-invasive examinations such as ultrasound, minimally invasive examinations such as angio-MRI and MDCT, or invasive examinations such as DSA and IVUS. DSA examinations are used to confirm significant stenosis or occlusion of a vessel, particularly when qualifying a patient for endovascular treatment. Due to their anatomic location, the superficial femoral artery and the popliteal artery are subject to various forces e.g. those exerted by the working muscles. Mechanical thrombectomy and atherectomy are efficient methods of arterial recanalization used in the treatment of acute, subacute or even chronic occlusions or stenosis of peripheral vessels. Conclusions: Frequency of angioplasty and

  16. Heparin-Coated Coronary Stents.

    PubMed

    van Der Giessen WJ; van Beusekom HM; Larsson; Serruys

    1999-09-01

    The development of the heparin-coated (HC)-stent should be viewed against the backdrop of the early unfavorable results with noncoated stents in the pre-intravascular ultrasound and pre-ticlopidine era. Notwithstanding, results of pilot and randomized trials show a surprisingly low incidence of (sub)acute stent thrombosis under challenging circumstances, such as acute coronary syndromes. Considering the quite low incidence of early complications with noncoated second-generation stents, it may require large trials to prove the clinical efficacy of the heparin- coating against noncoated devices. However, even if the "added value" of the heparin-coating will never be clinically proven, it has helped to enhance the penetration of stent therapy in interventional cardiology. Unlike the situation in 1992, very few cardiologists will now disagree with the statement that stents contribute to the state-of-the-art treatment of patients with angina pectoris or acute myocardial infarction. A preliminary comparison of available trials also suggests that the heparin-coated Palmaz-Schatz stent (Cordis Corp., Waterloo, Belgium) is as effective as the noncoated stent plus abciximab treatment.

  17. Are Aortic Stent Grafts Safe in Pregnancy?

    PubMed Central

    Khandanpour, Nader; Mehta, Tapan A.; Adiseshiah, M.; Meyer, Felicity J.

    2015-01-01

    Aortic stent grafts are increasingly used to treat aortic aneurysms and also other aortic pathologies. The safety of aortic stent grafts in pregnancy has never been studied or reported. We report on two cases of aortic stent grafts in pregnant women and discuss the effect of pregnancy on these aortic stent grafts. PMID:26229702

  18. Developments in metallic biodegradable stents.

    PubMed

    Hermawan, H; Dubé, D; Mantovani, D

    2010-05-01

    Interest in metallic degradable biomaterials research has been growing in the last decade. Both scientific journals and patent databases record a high increase in publications in this area. Biomedical implants with temporary function, such as coronary stents, are the targeted applications for this novel class of biomaterials. It is expected that stents made of degradable biomaterials, named biodegradable stents, will provide a temporary opening into a narrowed arterial vessel until the vessel remodels and will progressively disappear thereafter. Biodegradable stents made of metal have recently been progressed into preclinical tests in humans after their first introduction in early 2000s. By referring to patents and journal publications, this paper reviews the developments in biodegradable stents, with emphasis on those made of metals, starting from the first design ideas to validation testing.

  19. Carotid Artery Stenting: Single-Center Experience Over 11 Years

    SciTech Connect

    Nolz, Richard Schernthaner, Ruediger Egbert; Cejna, Manfred; Schernthaner, Melanie Lammer, Johannes Schoder, Maria

    2010-04-15

    This article reports the results of carotid artery stenting during an 11-year period. Data from 168 carotid artery stenting procedures (symptomatic, n = 55; asymptomatic, n = 101; symptoms not accessible, n = 12) were retrospectively collected. Primary technical success rate, neurological events in-hospital, access-site complications, and contrast-induced nephropathy (n = 118) were evaluated. To evaluate the influence of experience in carotid artery stenting on intraprocedural neurologic complications, patients were divided into two groups. Group 1 included the first 80 treated patients, and group 2 the remainder of the patients (n = 88). In-stent restenoses at last-follow-up examinations (n = 89) were assessed. The overall primary technical success rate was 95.8%. The in-hospital stroke-death rate was 3.0% (n = 5; symptomatic, 5.4%; asymptomatic, 2.0%; p = 0.346). Neurologic complications were markedly higher in group 1 (4.2%; three major strokes; symptomatic, 2.8%, asymptomatic, 1.4%) compared to group 2 (2.4%; one major and one minor stroke-symptomatic, 1.2%, asymptomatic 1.2%), but this was not statistically significant. Further complications were access-site complications in 12 (7.1%), with surgical revision required in 1 (0.6%) and mild contrast-induced nephropathy in 1 (0.85%). Twenty-one (23.6%) patients had >50% in-stent restenosis during a mean follow-up of 28.2 months. In conclusion, advanced experience in carotid artery stenting leads to an acceptable periprocedural stroke-death rate. In-stent restenosis could be a critical factor during the follow-up course.

  20. Mechanisms of Stroke after Intracranial Angioplasty and Stenting in the SAMMPRIS Trial

    PubMed Central

    Derdeyn, Colin P; Fiorella, David; Lynn, Michael J; Rumboldt, Zoran; Cloft, Harry J.; Gibson, Daniel; Turan, Tanya N.; Lane, Bethany F.; Janis, L. Scott; Chimowitz, Marc I.

    2013-01-01

    Background Enrollment in the Stenting and Aggressive Medical Management for the Prevention of stroke in Intracranial Stenosis (SAMMPRIS) trial was halted owing to higher than expected 30-day stroke rates in the stenting arm. Improvement in peri-procedural stroke rates from angioplasty and stenting for intracranial atherosclerotic disease (ICAD) requires an understanding of the mechanisms of these events. Objective To identify the types and mechanisms of peri-procedural stroke after angioplasty and stenting for ICAD. Methods Patients that suffered a hemorrhagic or ischemic stroke or a cerebral infarct with temporary signs (CITS) within 30 days of attempted angioplasty and stenting in SAMMPRIS were identified. Study records, including case report forms, procedure notes, and imaging were reviewed. Strokes were categorized as ischemic or hemorrhagic. Ischemic strokes were categorized as perforator territory, distal embolic, or delayed stent thrombosis. Hemorrhagic strokes were categorized as subarachnoid or intraparenchymal. Causes of hemorrhage (wire perforation, vessel rupture) were recorded. Results Three patients suffered an ischemic stroke after diagnostic angiography. Two were unrelated to the procedure. Twenty-one patients suffered an ischemic stroke (n= 19) or CITS (n=2) within 30 days of angioplasty and stenting. Most (n=15) were perforator territory and many of these occurred after angiographically successful angioplasty and stenting of the basilar artery (n = 8). Six patients suffered subarachnoid hemorrhage (three from wire perforation) and seven a delayed intraparenchymal hemorrhage. Conclusion Efforts at reducing complications from angioplasty and stenting for ICAD must focus on reducing the risks of regional perforator infarction, delayed intraparenchymal hemorrhage, and wire perforation. PMID:23328689

  1. Combined Arterial Infusion and Stent Implantation Compared with Metal Stent Alone in Treatment of Malignant Gastroduodenal Obstruction

    SciTech Connect

    Wang Zhongmin; Chen Kemin; Gong Ju; Zheng Yunfeng; Wang Tianxiang

    2009-09-15

    .38 to 1.48 (p < 0.01). There were no short-term complications. Late complications including hematemesis (n = 3), migration (n = 12), and stent occlusion due to tumor overgrowth (n = 5) were evenly distributed between the groups. In the DIT group chemotherapy-induced neutropenia and transient renal dysfunction were detected in six patients, which improved after symptomatic management. Mean survival time after the procedure was 5.9 and 11.1 months for MSI and DIT, respectively (P < 0.001). In conclusion, both MSI and DIT offer effective palliation for malignant gastroduodenal obstruction, but DIT appears to offer superior survival over MSI alone. Ideally, a prospective randomized trial comparing these two techniques should be carried out to validate this result.

  2. Ureteral stents: new ideas, new designs

    PubMed Central

    Al-Aown, Abdulrahman; Kyriazis, Iason; Kallidonis, Panagiotis; Kraniotis, Pantelis; Rigopoulos, Christos; Karnabatidis, Dimitrios; Petsas, Theodore; Liatsikos, Evangelos

    2010-01-01

    Ureteral stents represent a minimally invasive alternative to preserve urinary drainage whenever ureteral patency is deteriorated or is under a significant risk to be occluded due to extrinsic or intrinsic etiologies. The ideal stent that would combine perfect long-term efficacy with no stent-related morbidity is still lacking and stent usage is associated with several adverse effects that limit its value as a tool for long-term urinary drainage. Several new ideas on stent design, composition material and stent coating currently under evaluation, foreseen to eliminate the aforementioned drawbacks of ureteral stent usage. In this article we review the currently applied novel ideas and new designs of ureteral stents. Moreover, we evaluate potential future prospects of ureteral stent development adopted mostly by the pioneering cardiovascular stent industry, focusing, however, on the differences between ureteral and endothelial tissue. PMID:21789086

  3. Recommendations for Carotid Stenting in Korea

    PubMed Central

    Chang, Hyuk Won; Suh, Sang-il; Jeong, Hae Woong; Suh, Dae Chul

    2015-01-01

    Carotid artery angioplasty with stenting (CAS) is being performed in many hospitals in Korea. Most of the guidelines which are being used are similar, but the practical aspects such as techniques are different between hospitals. For example, usage of various protective devices, the oral antiplatelet regimen prior to procedure and placing of temporary pacemaker to prevent bradycardia are different between hospitals. In this article, we summarize and propose the guidelines for CAS which is currently being accepted in Korea. These guidelines may be helpful in providing protocol to neurointerventionalist who perform CAS and to standardize the process including reporting of CAS in the future comparative trials in Korea. PMID:25763292

  4. Encrustation of the Ureteral Double J Stent in Patients with a Solitary Functional Kidney – a Case Report

    PubMed Central

    Milicevic, Snjezana; Bijelic, Radojka; Jakovljevic, Branislava

    2015-01-01

    Introduction: The efficacy of ureteric stents in the management of various urological conditions causing the upper urinary tract obstruction has been extensively proven, and their contribution to urology remains enormous. The clinical use of ureteric stents is associated with several complications. “Stent syndrome,” encrustation, migration and urothelial hyperplasia are the most common problems related to long-term ureteral stenting. Case report: This work presents an interesting case from our practice: a complete encrustation of a classical polyurethane double J stent two and a half months after its initial instillation, in a 70 year old man, with a solitary functioning kidney, as well as successful removal of it by using a simultaneous treatment of extracorporeal lithotripsy and ureteroscopy with a contact disintegration of encrustations and with percutaneous nephrostomy, as an auxiliary procedure for providing of additional urine derivation. Conclusion: These problems can be overcome by the introduction of new advanced ureteral stent designs and biomaterials. PMID:26543316

  5. Endosonography-guided drainage of malignant fluid collections using lumen-apposing, fully covered self-expanding metal stents.

    PubMed

    Musumba, Crispin; Tutticci, Nicholas; Nanda, Kavinderjit; Kwan, Vu

    2014-08-01

    Endosonography (EUS)-guided drainage of paragastric fluid collections using fully covered self-expanding metal stents (FCSEMS) is now a well-established procedure. Recently, new and specially designed lumen-apposing, fully-covered metal cystgastrostomy stents have been employed for this indication. In this case series, the use of these new stents for the drainage of malignant fluid collections in three symptomatic patients is described. Cases included a large pancreatic pseudocyst, secondary to underlying acute lymphoblastic leukemia, and two large collections of loculated ascites due to metastatic ovarian and cervical cancer, respectively. Technical success in inserting the new stents was achieved in all three patients, and resulted in symptomatic relief. There were no clinically significant complications directly attributed to the stents. These new lumen-apposing cystgastrostomy stents may provide a viable, minimally invasive, and effective alternative for drainage of malignant fluid collections, either for definitive treatment or for palliation of symptoms.

  6. Plastic biliary stents for malignant biliary diseases.

    PubMed

    Huibregtse, Inge; Fockens, Paul

    2011-07-01

    Plastic biliary endoprostheses have not changed much since their introduction more than 3 decades ago. Although their use has been challenged by the introduction of metal stents, plastic stents still remain commonly used. Much work has been done to improve the problem of stent obstruction but without substantial clinical success. In this review, the authors discuss the history of plastic biliary stent development and the current use of plastic stents for malignant biliary diseases.

  7. Juxtarenal Modular Aortic Stent Graft Infection Caused by Staphylococcus aureus

    PubMed Central

    Novotný, Róbert; Mitáš, Petr; Hlubocký, Jaroslav; Hrubý, Ján; Slautin, Andrey; Špunda, Rudolf; Lindner, Jaroslav

    2016-01-01

    Introduction. We are presenting a case report of an infected modular abdominal stent graft. Case Presentation. A 67-year-old male patient three years after Cook's modular abdominal aortic aneurysm (AAA) graft implantation for juxtarenal AAA with an implantation of a stent extension into the right common iliac artery for type Ib endoleak. The patient was admitted into our center in severe condition with suspected retroperitoneal bleeding. Computed tomography angiography (CTAG) confirmed retroperitoneal bleeding in the right common iliac artery. An urgent surgical revision was indicated; destructed arterial wall around the stent extension in the right common iliac artery was discovered. Due to the severe state of health of the patient, a resection of the infected stent and affected arterial wall was performed, followed by an iliac-femoral crossover bypass. The patient was transported to the intensive care unit with hepatic and renal failure, with maximal catecholamine support. Combined antibiotic treatment was started. The patient died five hours after the procedure. The cause of death was multiorgan failure caused by sepsis. Hemocultures and perioperative microbiological cultures showed the infection agent to be Staphylococcus aureus methicillin sensitive. Conclusion. Stent graft infection is a rare complication. Treatment is associated with high mortality and morbidity. PMID:26904354

  8. Treatment of acquired nasopharyngeal stenosis using a removable silicone stent.

    PubMed

    De Lorenzi, Davide; Bertoncello, Diana; Comastri, Stefano; Bottero, Enrico

    2015-02-01

    The aim of this prospective study was to characterise patient characteristics and the histories of cats with acquired nasopharyngeal stenosis (ANS), and to describe the use of a removable silicone stent for treatment. ANS was diagnosed in 15 cats with clinical signs present for a median of 4 months. Clinical signs included stertor and inspiratory difficulty, nasal discharge, sneezing, dysphagia, regurgitation, vomiting and anorexia. Radiographs revealed a dorsal deviation or deformation of the caudal part of the soft palate in 10 of the cats, a soft tissue density across the cranial nasopharynx in four and no abnormality in one. The stenosis was initially dilated with a Kelly forceps in 10 of the cats and by balloon dilatation in five. A segment of a 24 Fr silicone thoracic catheter was used for the stent in five cats; in the other 10 cats a segment of a 28 Fr catheter was used. The stent was removed after 3 weeks in 12 cats and after 4 weeks in the other three. Endoscopy revealed an adequate nasopharyngeal diameter in all of the cats. At both 3 and 10 months after surgery the response was considered to be satisfactory, with complete resolution of clinical signs in 14 cats and improvement in the remaining cat. The treatment of ANS by stenosis dilatation followed by temporary stenting with a silicone stent is a rapid, safe, economical and effective procedure.

  9. Temporary endoscopic metallic stent for idiopathic esophageal achalasia.

    PubMed

    Coppola, Franco; Gaia, Silvia; Rolle, Emanuela; Recchia, Serafino

    2014-02-01

    Idiopathic achalasia is a motor disorder of the esophagus of unknown etiology caused by loss of motor neurons determining an altered motility. It may determine severe symptoms such as progressive dysphagia, regurgitations, and pulmonary aspirations. Many therapeutic options may be offered to patients with achalasia, from surgery to endoscopic treatments such as pneumatic dilation, botulinum injection, peroral endoscopic myotomy, or endoscopic stenting. Recently, temporary placement of a stent was proposed by Cheng as therapy for achalasia disorders, whereas no Western authors have dealt with it up to date. The present study reports our preliminary experience in 7 patients with achalasia treated with a temporary stent. Partially covered self-expanding metallic stents (Micro-Tech, Nanjin, China) 80 mm long and 30 mm wide were placed under fluoroscopic control and removed after 6 days. Clinical follow-up was scheduled to check endoscopic success, symptoms release, and complications. The placement and the removal of the stents were obtained in all patients without complications. Mean clinical follow-up was 19 months. Five out of 7 patients referred total symptoms release and 2 experienced significant improvement of dysphagia. The procedure was not time consuming and was safe; no mild or severe complications were registered. In conclusion, our results may suggest a possible safe and effective endoscopic alternative treatment in patients with achalasia; however, further larger studies are necessary to confirm these promising, but very preliminary, data.

  10. Angioplasty or Primary Stenting for Infrapopliteal Lesions: Results of a Prospective Randomized Trial

    SciTech Connect

    Randon, C. Jacobs, B.; De Ryck, F.; Vermassen, F.

    2010-04-15

    Excellent results with small stents in coronary arteries have led endovascular therapists to their use in infrapopliteal vessels. However, to date no level I evidence exists to recommend primary stenting over infrapopliteal angioplasty alone. The aim of this randomized single-center trial was to compare their 1-year outcome. A total of 38 limbs in 35 patients with critical limb ischemia were randomized to angioplasty (22 pts) or primary stenting (16 pts). Target lesions were infrapopliteal occluded (36) or stenotic (20) lesions ranging from <2 to >15 cm in length. The mean age was 72 years. At 12 months, there was no statistical difference in survival (angioplasty, 69.3%; primary stenting, 74.7%), in limb salvage (angioplasty, 90%; primary stenting, 91.7%), or in primary and secondary patency (angioplasty, 66 and 79.5%; primary stenting, 56 and 64%) between the groups Renal insufficiency was the only significant negative predicting factor for limb salvage in both groups. In conclusion, the 1-year results for both groups were broadly similar. Stenting has its place in infrapopliteal angioplasty if the procedure is jeopardized by a dissection or recoil, but our results do not support primary stenting in all cases.

  11. Safety and efficacy of AVE gfx stent implantation via 6 Fr guiding catheters.

    PubMed

    Kiemeneij, F; Laarman, G J; Odekerken, D; Slagboom, T; van der Wieken, R

    1999-08-01

    This prospective study was designed to determine the feasibility of AVE gfx premounted stent systems in combination with 6 Fr guides. Between 1 April and 12 August 1997, 230 patients underwent AVE gfx coronary stent implantation via 6 Fr guides. The radial approach was used in 146 patients (63.5%). In 230 procedures (293 lesions), 237 guiding catheters were used. A total of 331 AVE gfx stents were implanted, 1.4 per patient. Backup, opacification, and friction were considered good in 85.8%, 96.4%, and 76.7%, respectively. Slight and severe friction was felt during combined use of long (> or = 18 mm), large-sized (3.5 mm) stents and small-sized guiding catheters (inner diameter, 0.061-0.062"). The presence of a second protecting guidewire impaired passage of the AVE gfx stent, also in large 6 Fr guides (ID 0.064"). Of 331, 320 (96.7%) stents were successfully deployed at the initial attempt. Ten stents (3%) had to be retrieved. Six of these were successfully placed at a second attempt and three slipped off the balloon, all successfully retrieved from the patient's circulation. At 1 month, 217 patients (94.4%) were free of events. The AVE gfx stent is compatible with 6 Fr guiding catheters. Use of new-generation, large-bore 6 Fr gc (> or = 0.064") is recommended.

  12. [Finite Element Analysis of Effect of Key Dimension of Nitinol Stent on Its Fatigue Behaviour].

    PubMed

    Li, Jianjun; Wang, Shengzhang

    2015-04-01

    To evaluate the fatigue behavior of nitinol stents, we used the finite element method to simulate the manufacture processes of nitinol stents, including expanding, annealing, crimping, and releasing procedure in applications of the clinical treatments. Meanwhile, we also studied the effect of the crown area dimension of stent on strain distribution. We then applied a fatigue diagram to investigate the fatigue characteristics of nitinol stents. The results showed that the maximum strain of all three stent structures, which had different crown area dimensions under vessel loads, located at the transition area between the crown and the strut, but comparable deformation appeared at the inner side of the crown area center. The cause, of these results was that the difference of the area moment of inertia determined by the crown dimension induced the difference of strain distribution in stent structure. Moreover, it can be drawn from the fatigue diagrams that the fatigue performance got the best result when the crown area dimension equaled to the intermediate value. The above results proved that the fatigue property of nitinol stent had a close relationship with the dimension of stent crown area, but there was no positive correlation.

  13. [Perioperative management of patients with coronary stents in non-cardiac surgery].

    PubMed

    Jámbor, C; Spannagl, M; Zwissler, B

    2009-10-01

    In patients with coronary stents scheduled for surgery the question arises whether and how antiplatelet therapy should be continued. Risks of perioperative bleeding and of acute stent thrombosis have to be considered simultaneously. The bleeding risk depends primarily on the kind of surgery and on patient comorbidity. The risk of stent thrombosis is increased in these patients due to the thrombogenic surface of the stents. The main determinants are hereby the time duration after stent implantation, the kind of the stent [uncoated (bare-metal stent, BMS) or coated (drug-eluting stent, DES)], as well as angiographic and clinical patient factors. Therefore, perioperative antiplatelet therapy has to be individually adapted for each patient. Bridging with heparin is ineffective. Bridging with intravenous antiplatelet drugs during the perioperative interruption of oral antiplatelet therapy might be a potential procedure in high-risk patients. Whether bedside monitoring of antiplatelet therapy improves the perioperative management of these patients and reduces adverse outcome is object of current studies.

  14. Helical CT Angiography of Abdominal Aortic Aneurysms Treated with Suprarenal Stent Grafting: A Pictorial Essay

    SciTech Connect

    Sun Zhonghua

    2003-06-15

    The endovascular repair of abdominal aorticaneurysm (AAA) with stent grafts is rapidly becoming an important alternative to open repair. Suprarenal stent grafting, recently modified from conventional infrarenal stent grafting, is a technique for the purpose of treating patients with inappropriate aneurysm necks.Unlike open repair, the success of endoluminal repair cannot be ascertained by means of direct examination and thus relies on imaging results. The use of conventional angiography for arterial imaging has become less dominant, while helical computed tomography angiography(CTA) has become the imaging modality of choice for both preoperative assessment and postoperative followup after treatment with stent graft implants. There is an increasing likelihood that radiologists will become more and more involved in the procedure of aortic stent grafting and in giving the radiological report on these patients treated with stent grafts. It is necessary for radiologists to be familiar with the imaging findings, including common and uncommon appearances following aortic stent grafting. The purpose of this pictorial essay is to describe and present normal and abnormal imaging appearances following aortic stent grafting based on helical CTA.

  15. Clinical features and patency rates of Remedy® biodegradable peripheral stents

    PubMed Central

    Tiryakioglu, Selma Kenar; Tiryakioglu, Osman; Karahan, Oguz; Demirtas, Sinan; Gokalp, Fatih; Erkoc, Kamuran; Özkan, Hakan; Ozyazicioglu, Ahmet

    2016-01-01

    Summary Objective: The aim of this study was to investigate the mid-term results of Remedy® biodegradable stents, which have recently come into use for lower-extremity arterial occlusive disease. Methods: Sixty-five patients, who underwent surgical intervention in various cardiovascular surgery clinics throughout Turkey, were included in the study. The total number of stents used was 92. The mean age of the patients was 64.11 ± 24.13 years (20–82), and 16 (24.6%) were female. The mean number of stents per patient was 1.42, and 70.7% of the lesions were TASC type A. Patients were followed for a mean of 32 months. Sixty-five patients underwent a control examination using either digital subtraction angiography or colour Doppler ultrasonography. In-stent restenosis was defined as ≥ 50% stenosis in the stent area in asymptomatic patients. The procedure was repeated if the degree of stenosis was ≥ 70%. Results During the follow-up period, restenosis (≥ 50% stenosis) was observed in seven patients (10.7%). The patency rate after secondary intervention was 100%, and there was no loss of limbs in any patient. Restenosis was observed in six patients with superficial femoral artery stents, and in one patient with a popliteal arterial stent. Conclusion Our experience shows that Remedy® biodegradable peripheral stents were safe and effective in our cohort of patients, with acceptable patency rates. PMID:26813981

  16. The role of stents in the treatment of congenital heart disease: Current status and future perspectives

    PubMed Central

    Peters, Bjoern; Ewert, Peter; Berger, Felix

    2009-01-01

    Intravascular or intracardiac stenoses occur in many forms of congenital heart disease (CHD). Therefore, the implantation of stents has become an accepted interventional procedure for stenotic lesions in pediatric cardiology. Furthermore, stents are know to be used to exclude vessel aneurysm or to ensure patency of existing or newly created intracardiac communications. With the further refinement of the first generation of devices, a variety of “modern” stents with different design characteristics have evolved. Despite the tremendous technical improvement over the last 20 years, the “ideal stent” has not yet been developed. Therefore, the pediatric interventionalist has to decide which stent is suitable for each lesion. On this basis, currently available stents are discussed in regard to their advantages and disadvantages for common application in CHD. New concepts and designs developed to overcome some of the existing problems, like the failure of adaptation to somatic growth, are presented. Thus, in the future, biodegradable or growth stents might replace the currently used generation of stents. This might truly lead to widening indications for the use of stents in the treatment of CHD. PMID:20300265

  17. Efficacy of a dual-ring wound protector for prevention of incisional surgical site infection after Whipple's procedure (pancreaticoduodenectomy) with preoperatively-placed intrabiliary stents: protocol for a randomised controlled trial

    PubMed Central

    Bressan, Alexsander K; Roberts, Derek J; Edwards, Janet P; Bhatti, Sana U; Dixon, Elijah; Sutherland, Francis R; Bathe, Oliver; Ball, Chad G

    2014-01-01

    Introduction Among surgical oncology patients, incisional surgical site infection is associated with substantially increased morbidity, mortality and healthcare costs. Moreover, while adults undergoing pancreaticoduodenectomy with preoperative placement of an intrabiliary stent have a high risk of this type of infection, and wound protectors may significantly reduce its risk, no relevant studies of wound protectors yet exist involving this patient population. This study will evaluate the efficacy of a dual-ring wound protector for prevention of incisional surgical site infection among adults undergoing pancreaticoduodenectomy with preoperatively-placed intrabiliary stents. Methods and analysis This study will be a parallel, dual-arm, randomised controlled trial that will utilise a more explanatory than pragmatic attitude. All adults (≥18 years) undergoing a pancreaticoduodenectomy at the Foothills Medical Centre in Calgary, Alberta, Canada with preoperative placement of an intrabiliary stent will be considered eligible. Exclusion criteria will include patient age <18 years and those receiving long-term glucocorticoids. The trial will employ block randomisation to allocate patients to a commercial dual-ring wound protector (the Alexis Wound Protector) or no wound protector and the current standard of care. The main outcome measure will be the rate of surgical site infection as defined by the Centers for Disease Control and Prevention criteria within 30 days of the index operation date as determined by a research assistant blinded to treatment allocation. Outcomes will be analysed by a statistician blinded to allocation status by calculating risk ratios and 95% CIs and compared using Fisher's exact test. Ethics and dissemination This will be the first randomised trial to evaluate the efficacy of a dual-ring wound protector for prevention of incisional surgical site infection among patients undergoing pancreaticoduodenectomy. Results of this study are expected

  18. Present and future of endovascular SFA treatment: stents, stent-grafts, drug coated balloons and drug coated stents.

    PubMed

    Bosiers, M; Deloose, K; Verbist, J; Peeters, P

    2008-04-01

    The current evolution towards treating more complex femoropopliteal lesions as seen in the renewed TASC II recommendations clearly reflects the continuous evolutions in femoropopliteal stent design. Recent stent design improvements focus on decreasing stent fractures rates which can negatively impact patency rates. By rearranging strut alignment towards helical connecting bridges or full helical stent designs, stent designers have successfully improved the fracture resistance of their stents. The superior fracture resistance of the latest stent generation in combination with the production of long nitinol stents of up to 20 cm in length allow that more difficult and complex lesions can be treated endovascularly. The continuous perfection of nitinol stent platforms followed by the transfer of coronary technologies (e.g. active coatings) towards peripheral devices might broaden the indications for the minimal invasive strategy towards TransAtlantic Inter-Society Consensus (TASC) II C&D lesions.

  19. Clinical results of carotid artery stenting versus carotid endarterectomy

    PubMed Central

    Akinci, Tuba; Derle, Eda; Kibaroğlu, Seda; Harman, Ali; Kural, Feride; Cınar, Pınar; Kilinc, Munire; Akay, Hakki T.; Can, Ufuk; Benli, Ulku S.

    2016-01-01

    Objective: To review our results of carotid artery stenting (CAS) and carotid endarterectomy (CEA). Methods: We evaluated the medical records of patients undergoing carotid artery revascularization procedure, between 2001 and 2013 in Baskent University Hospital, Ankara, Turkey. Carotid artery stenting or CEA procedures were performed in patients with asymptomatic carotid stenosis (≥70%) or symptomatic stenosis (≥50%). Demographic data, procedural details, and clinical outcomes were recorded. Primary outcome measures were in 30-day stroke/transient ischemic attacks (TIA)/amaurosis fugax or death. Secondary outcome measures were nerve injury, bleeding complications, length of stay in hospital, stroke, restenosis (ICA patency), and all-cause death during long-term follow-up. Results: One hundred ninety-four CEA and 115 CAS procedures were performed for symptomatic and/or asymptomatic carotid artery stenosis. There is no significant differences 30-day mortality and neurologic morbidity between CAS (13%) and CEA procedures (7.7%). Length of stay in hospital were significantly longer in CEA group (p=0.001). In the post-procedural follow up, only in symptomatic patients, restenosis rate was higher in the CEA group (p=.045). The other endpoints did not differ significantly. Conclusions: Endovascular stent treatment of carotid artery atherosclerotic disease is an alternative for vascular surgery, especially for patients that are high risk for standard CEA. The increasing experience, development of cerebral protection systems and new treatment protocols increases CAS feasibility. PMID:27744460

  20. [Larynx: implants and stents].

    PubMed

    Sittel, C

    2009-05-01

    There is a wide variety of devices and materials to be implanted into the human larynx. Some are intended to remain only for a period of time, like laryngeal stents. If removal is not intended the device meets the definition for a medical implant. The majority of implants is used for the treatment of unilateral vocal fold immobility. There a 2 types of implants serving this purpose: Implants in a stricter sense are devices of solid material, which are brought into the paraglottic space through a window in the laryngeal framework (medialization thyroplasty). Several different products are presented in this review. In contrast, there are different substances available for endoscopic injection into the paralyzed vocal fold (injection laryngoplasty). Since some of these substances show a corpuscular consistency and a high viscosity they need to be deposited into the lateral paraglottic space. Therefore, the term "injectable implants" has been coined for these materials. The different substances available are discussed in detail in this review. Laryngeal stents are primarily used in the early postoperative phase after open reconstruction of the larynx. The different devices available on the market are described with their specific characteristics and intended use.

  1. Successful percutaneous stent implantation for isolated dismal transverse aortic arch kinking

    PubMed Central

    Zuo, Zhi-Liang; Tsauo, Jia-Yu; Chen, Mao; Feng, Yuan

    2017-01-01

    Abstract Rationale: Isolated dismal transverse aortic arch kinking in adults is rare, and there is no recommended therapy at present. Percutaneous stent implantation may be an effective method to correct it and could be considered. Patient concerns: We report a 46-year-old woman who suffered from recurrent migraine and refractory hypertension with a significant systolic blood pressure difference between upper limbs. Diagnoses: The woman was diagnosed with isolated dismal transverse aortic arch kinking with refractory hypertension. Interventions: Percutaneous stent implantation was performed. Due to the kinking nature of the diseased transverse aortic arch, the first covered stent moved forward to the proximal transverse aortic arch during deploying without the left common carotid artery occlusion. And then, a second stent was placed to cover the residual kinked part of the dismal transverse arch. Outcomes: Angiography and post-procedural computed tomography angiography revealed fully corrected of the diseased segment. At 6-month follow-up after procedure, the patient was free of any symptoms and had a normal blood pressure under antihypertensive treatment. Lessons: This case indicates that transverse aortic arch kinking in isolation can be well treated by percutaneous stent implantation in adult patients. Unlike pure aortic coarctation, elongation and bucking give the rise to the occurrence rate of stent sliding and migration and sometimes a second stent is needed. PMID:28272200

  2. Endoscopic Removal of a Nitinol Mesh Stent from the Ureteropelvic Junction after 15 Years

    PubMed Central

    Smrkolj, Tomaž; Šalinović, Domagoj

    2015-01-01

    We report a rare case of a patient with a large stone encrusted on a nitinol mesh stent in the ureteropelvic junction. The stent was inserted in the year 2000 after failure of two pyeloplasty procedures performed due to symptomatic ureteropelvic junction stenosis. By combining minimally invasive urinary stone therapies—extracorporeal shock wave lithotripsy, semirigid ureterorenoscopy with laser lithotripsy, and percutaneous nephrolithotomy—it was possible to completely remove the encrusted stone and nitinol mesh stent that was implanted for 15 years, rendering the patient symptom and obstruction free. PMID:26697258

  3. Bare metal or drug-eluting stent implantation in last remaining vessel PCI? A serious dilemma.

    PubMed

    Zhang, Lei; Zhu, Jianhua; Kiemeneij, Ferdinand

    2009-04-01

    This case report describes the treatment of an old male diabetic patient with last remaining vessel coronary artery disease and poor left ventricular function. In presence of an old occlusion of the left main coronary artery, a subtotal stenosis of a dominant right coronary artery required angioplasty. After ample consideration it was decided to implant a bare metal stent (BMS) instead of a drug-eluting stent (DES). The major reason was the fear for early discontinuation of clopidogrel in case a drug-eluting stent was placed. The procedure and follow-up are described followed by an overview of current literature concerning similar pathology.

  4. Stent graft exclusion of a pseudoaneurysm in a Blalock-Taussig shunt.

    PubMed

    Sanchez-Recalde, Angel; Garzón, Gonzalo; Oliver, José M

    2010-08-01

    This case is the first report of slow-growing pseudoaneurysm after vessel dissection secondary to two stents implantation into classic Blalock Taussig shunt in a patient with pulmonary atresia and ventricular septal defect. Pseudoaneurysm was successfully excluded by a percutaneous approach with self-expandable stent graft deployment from the aorta to the middle of the Blalock Taussig shunt. Nearly 3 years after the procedure, the classic BT is patent, and there were no restenosis or thrombosis in spite of the very long length of the stented segment.

  5. Retrieval of the Protection Filter with a Soft Coaxial Catheter After Carotid Stenting

    SciTech Connect

    Mayer, Thomas E.; Holtmannspoetter, Markus; Mueller-Schunk, Stefanie

    2009-01-15

    The purpose of this study was to shorten and simplify the procedure of filter retrieval after carotid stenting with cerebral protecting devices. We propose a retrieval method with a soft-tip guiding catheter, which eliminates the step of balloon exchange and introduction of a retriever catheter for the protection filter. The technique was successfully used in our last 60 consecutive patients. One transient deficit occurred. In conclusion, retrieval of the filter with a soft coaxial catheter after carotid stenting is a feasible and safe method and may simplify cerebrovascular protection during stenting.

  6. Percutaneous Placement of Permanent Metallic Stents in the Cystic Duct to Treat Obstructive Cholecystitis.

    PubMed

    Brown, Nicholas I; Jhamb, Ashu; Brooks, Duncan M; Little, Andrew F

    2015-12-01

    This report presents a series of five patients unsuitable for surgery who had nonretrievable self-expanding metallic stents deployed along the cystic duct as treatment for benign and malignant causes of gallbladder obstruction. Techniques are described for draining cholecystitis, removing gallstones, bypassing gallbladder obstructions, and inserting metallic stents across the cystic duct to restore permanent antegrade gallbladder drainage in acute and chronic cholecystitis. Symptoms resolved in all cases, and stents remained patent for as long as 22 months. This procedure may be an effective alternative to cholecystectomy or long-term gallbladder drainage for patients in inoperable condition.

  7. Limitations of Endovascular Treatment with Stent-Grafts for Active Mycotic Thoracic Aortic Aneurysm

    SciTech Connect

    Ishida, Masaki; Kato, Noriyuki; Hirano, Tadanori; Shimono, Takatsugu; Yasuda, Fuyuhiko; Tanaka, Kuniyoshi; Yada, Isao; Takeda, Kan

    2002-06-15

    An 81-year-old woman with ruptured mycotic thoracic aortic aneurysm was treated with endovascular placement of stent-grafts fabricated from expanded polytetrafluoroethylene and Z-stents. Although exclusion of the aneurysm was achieved at the end of the procedure, a type I endoleak developed on the following day.Despite emergent surgical resection of the aneurysm and extra-anatomical reconstruction, the patient died 2 days later. Stent-graft repair may not be a suitable method for the treatment of ruptured mycotic aneurysm in the presence of active infection.

  8. Enteral metallic stenting by balloon enteroscopy for obstruction of surgically reconstructed intestine.

    PubMed

    Nakahara, Kazunari; Okuse, Chiaki; Matsumoto, Nobuyuki; Suetani, Keigo; Morita, Ryo; Michikawa, Yosuke; Ozawa, Shun-ichiro; Hosoya, Kosuke; Kobayashi, Shinjiro; Otsubo, Takehito; Itoh, Fumio

    2015-06-28

    We present three cases of self-expandable metallic stent (SEMS) placement using a balloon enteroscope (BE) and its overtube (OT) for malignant obstruction of surgically reconstructed intestine. A BE is effective for the insertion of an endoscope into the deep bowel. However, SEMS placement is impossible through the working channel, because the working channel of BE is too small and too long for the stent device. Therefore, we used a technique in which the BE is inserted as far as the stenotic area; thereafter, the BE is removed, leaving only the OT, and then the stent is placed by inserting the stent device through the OT. In the present three cases, a modification of this technique resulted in the successful placement of the SEMS for obstruction of surgically reconstructed intestine, and the procedures were performed without serious complications. We consider that the present procedure is extremely effective as a palliative treatment for distal bowel stenosis, such as in the surgically reconstructed intestine.

  9. Stenting of vertical vein in an infant with obstructed supracardiac total anomalous pulmonary venous drainage

    PubMed Central

    Lim, WK; Leong, MC; Samion, H

    2016-01-01

    A 1.7 kg infant with obstructed supracardiac total anomalous pulmonary venous drainage (TAPVD) presented with severe pulmonary hypertension secondary to vertical vein obstruction. The child, in addition, had a large omphalocele that was being managed conservatively. The combination of low weight, unoperated omphalocele, and severe pulmonary hypertension made corrective cardiac surgery very high-risk. Therefore, transcatheter stenting of the stenotic vertical vein, as a bridge to corrective surgery was carried out. The procedure was carried out through the right internal jugular vein (RIJ). The stenotic segment of the vertical vein was stented using a coronary stent. After procedure, the child was discharged well to the referred hospital for weight gain and spontaneous epithelialization of the omphalocele. Stenting of the vertical vein through the internal jugular vein can be considered in very small neonates as a bridge to repair obstructed supracardiac total anomalous venous drainage. PMID:27212859

  10. Magnetic Nanoparticle-Mediated Targeting of Cell Therapy Reduces In-Stent Stenosis in Injured Arteries.

    PubMed

    Polyak, Boris; Medved, Mikhail; Lazareva, Nina; Steele, Lindsay; Patel, Tirth; Rai, Ahmad; Rotenberg, Menahem Y; Wasko, Kimberly; Kohut, Andrew R; Sensenig, Richard; Friedman, Gary

    2016-09-19

    Although drug-eluting stents have dramatically reduced the recurrence of restenosis after vascular interventions, the nonselective antiproliferative drugs released from these devices significantly delay reendothelialization and vascular healing, increasing the risk of short- and long-term stent failure. Efficient repopulation of endothelial cells in the vessel wall following injury may limit complications, such as thrombosis, neoatherosclerosis, and restenosis, through reconstitution of a luminal barrier and cellular secretion of paracrine factors. We assessed the potential of magnetically mediated delivery of endothelial cells (ECs) to inhibit in-stent stenosis induced by mechanical injury in a rat carotid artery stent angioplasty model. ECs loaded with biodegradable superparamagnetic nanoparticles (MNPs) were administered at the distal end of the stented artery and localized to the stent using a brief exposure to a uniform magnetic field. After two months, magnetic localization of ECs demonstrated significant protection from stenosis at the distal part of the stent in the cell therapy group compared to both the proximal part of stent in the cell therapy group and the control (stented, nontreated) group: 1.7-fold (p < 0.001) less reduction in lumen diameter as measured by B-mode and color Doppler ultrasound, 2.3-fold (p < 0.001) less reduction in the ratios of peak systolic velocities as measured by pulsed wave Doppler ultrasound, and 2.1-fold (p < 0.001) attenuation of stenosis as determined through end point morphometric analysis. The study thus demonstrates that magnetically assisted delivery of ECs is a promising strategy for prevention of vessel lumen narrowing after stent angioplasty procedure.

  11. Palliation of Malignant Biliary and Duodenal Obstruction with Combined Metallic Stenting

    SciTech Connect

    Akinci, Devrim Akhan, Okan; Ozkan, Fuat; Ciftci, Turkmen; Ozkan, Orhan S.; Karcaaltincaba, Musturay; Ozmen, Mustafa N.

    2007-11-15

    Purpose. The purpose of this study is to evaluate the efficacy of palliation of malignant biliary and duodenal obstruction with combined metallic stenting under fluoroscopy guidance. Materials and Methods. A retrospective analysis of 9 patients (6 men and 3 women) who underwent biliary and duodenal stenting was performed. The mean age of patients was 61 years (range: 42-80 years). The causes of obstruction were pancreatic carcinoma in 7 patients, cholangiocellular carcinoma in one, and duodenal carcinoma in the other. Biliary and duodenal stents were placed simultaneously in 4 patients. In other 5 patients dudodenal stents were placed after biliary stenting when the duodenal obstruction symptoms have developed. In two patients duodenal stents were advanced via transgastric approach. Results. Technical success rate was 100 %. After percutaneous biliary drainage and stenting bilirubin levels decreased to normal levels in 6 patients and in remaining 3 patients mean reduction of 71% in bilirubin levels was achieved. Tumoral ingrowth occurred in one patient and percutaneous biliary restenting was performed 90 days after the initial procedure. Of the 9 patients, 6 patients were able to tolerate solid diet, whereas 2 patients could tolerate liquid diet and one patient did not show any improvement. Mean survival periods were 111 and 73 days after biliary and duodenal stenting, respectively. Conclusion. Combined biliary and duodenal stent placement which can be performed under fluoroscopic guidance without assistance of endoscopy is feasible and an effective method of palliation of malignant biliary and duodenal obstructions. If transoral and endoscopic approaches fail, percutaneous gastrostomy route allows duodenal stenting.

  12. Nonstented versus routine stented ureteroscopic holmium laser lithotripsy: a prospective randomized trial.

    PubMed

    Shao, Yi; Zhuo, Jian; Sun, Xiao-Wen; Wen, Wei; Liu, Hai-Tao; Xia, Shu-Jie

    2008-10-01

    We conducted a prospective, randomized study to evaluate whether postoperative ureteral stenting is necessary after ureteroscopic holmium laser lithotripsy. A total of 115 consecutive patients with distal or middle ureteral calculi amenable to ureteroscopic holmium laser lithotripsy were prospectively randomized into stented group (n = 58) and nonstented group (n = 57). The stent was routinely placed in the treated ureter for 2 weeks. The outcomes were measured with postoperative patient symptoms, stone-free rates, early and late postoperative complications, and cost-effectiveness. The postoperative symptoms were measured with Ureteral Stent Symptom Questionnaire (USSQ). All patients completed a 12-week follow-up. There was no significant difference between two groups with respect to the patient age, stone size, stone location and mean operative time. According to the USSQ, the symptoms of the stented group were significantly worse compared to the nonstented group (P = 0.0001). In the stented group, two patients had high fever for 1 week after the operation, stent migration was found in two patients, and the stents had to be removed earlier in five patients because of severe pain or hematuria. The cost of the stented group was significantly higher than the nonstented group. The stone-free rate was 100% in both groups. No hydronephrosis or ureteral stricture was detected by intravenous pyelogram in the 12th week postoperative follow-up. In conclusion, we believe that routine stenting after ureteroscopic intracorporeal lithotripsy with the holmium laser is not necessary as long as the procedure is uncomplicated for distal or middle ureteral calculis less than 2 cm.

  13. Long-term tolerance of airway silicone stent in patients with post-tuberculosis tracheobronchial stenosis.

    PubMed

    Verma, Akash; Um, Sang-Won; Koh, Won-Jung; Suh, Gee Young; Chung, Man Pyo; Kwon, O Jung; Kim, Hojoong

    2012-01-01

    Surgery is a well-recognized modality of treatment for benign tracheobronchial stenosis. However, in some benign disease groups, such as tuberculosis, sarcoidosis, war gas exposure, and inhalation burns, multiplicity of involvement or long length of stenosed segment heightens surgical challenge. We investigated the outcomes and long-term tolerability of the Natural stent (N-stent) in such patients with post-tuberculosis tracheobronchial stenosis. A retrospective review was done for 17 patients who underwent silicone stenting (N-stent) for post-tuberculosis tracheobronchial stenosis during January 2000-December 2003 but needed persistent stent placement and still require the stent. Significant increase in the ratio of forced expiratory volume in 1 second (FEV1) to forced vital capacity (FVC), expressed as FEV1%, as well as in forced percentual vital capacity (FVC%) (Δ24% and Δ11%, respectively) in the short term and sustained increase in the FEV1% and FVC% (Δ26.5% and Δ16.5%, respectively) in the long term were noted at a median (range) interval of 1 (0.5-72) month and 72 (12-114) months, respectively, along with symptomatic relief. No procedure-related death occurred. Stent-related late complications included granulation tissue formation (76%), migration (70%), and mucostasis (17%). The median duration for which N-stents were tolerated was 7.9 (range, 3-11) years. N-stents are well-tolerated for a prolonged period. Stent-related complications occur, but are easily managed. These results might carry medical implications for those who have airway lesions difficult to correct surgically.

  14. Advances in Ureteral Stent Design

    NASA Astrophysics Data System (ADS)

    Denstedt, John D.

    2007-04-01

    Ureteral stents are commonly used in urolithiasis patients for relief of obstruction or in association with stone treatments such as ureteroscopy and extracorporeal shock wave lithotripsy. There are currently many different bulk materials and coatings available for the manufacture of ureteral stents, however the ideal material has yet to be discovered. All potential biomaterials must undergo rigorous physical and biocompatibility testing before commercialization and use in humans. Despite significant advances in basic science research involving biocompatibility issues and biofilm formation, infection and encrustation remain associated with the use of biomaterials in the urinary tract. There have been many significant advances in the design of ureteral stents in recent years and these will be highlighted along with a discussion of future aspects of biomaterials and use of stents in association with urolithiasis.

  15. Emergency cricothyroidotomy following tracheobronchial stenting.

    PubMed

    Cavinato, Simon Robert; Denning, Mike; Madden, Brendan P

    2017-02-24

    A man aged 51 years was referred for tracheobronchial stenting after a poorly differentiated oesophageal carcinoma had progressed to cause stridor. Bronchoscopy revealed a left vocal cord palsy and tumour infiltration into the trachea. A tracheobronchial stent was placed, and after distal migration was endoscopically resited. Returning from theatre, the patient developed severe upper airway obstruction that progressed to cause CO2 narcosis and loss of consciousness. A rapid sequence induction was initiated, and a Glidescope revealed bilateral vocal cord palsy with severe oedema causing an inability to pass a tube or stylet. Tracheostomy was attempted above the suprasternal notch but was obstructed by the stent. Oxygen saturations dropped steadily, reaching as low as 38%. Emergency cricothyroidotomy was performed, compliant with DAS guidelines, that proved successful. The stent was removed, which was blocked with blood and secretions, and tracheostomy was placed 2 days later. The patient made a full neurological recovery.

  16. Clinical and angiographic results with the NIR stent: First International NIR Endovascular Stent Study (FINESS-II).

    PubMed

    Rutsch, Wolfgang; Kiemeneij, Ferdinand; Colombo, Antonio; Macaya, Carlos; Guermonprez, Jean-Leon; Grip, Lars; Hamburger, Jaap; Umans, Victor; Gotsman, Mervyn; Almagor, Yaron; Morice, Marie-Claude; Garcia, Eulogio; Chevalier, Bernard; Erbel, Raimund; Cobaugh, Michael; Morel, Marie-Angèle; Serruys, Patrick W

    2000-09-01

    BACKGROUND: Although safety and efficacy of the NIR trade mark stent have been reported, the long-term angiographic and clinical outcomes have yet to be investigated. The FINESS-II study (First International NIR Endovascular Stent Study) was designed to assess the procedural safety of single 9 and 16 mm NIR stent implantation, the six-month restenosis rate and finally the six- and 12-month clinical outcome of patients treated with this novel coronary stent. METHODS: Patients with angina and a single de novo lesion in a native coronary artery of >3 and <5 mm diameter were included in this multicentre, prospective, observational trial. Clinical follow-up was obtained at one, six and 12 months. Angiography was performed before and after the stent implantation and at six months. The primary endpoint included major adverse cardiac events (death, myocardial infarction and target lesion revascularization) within 30 days after the procedure. Major bleeding complications and subacute stent thrombosis within the first 30 days were also reported as specific endpoints. Secondary endpoints were major cardiac-event-free survival at six- and 12-month follow-up and angiographic restenosis at six months. RESULTS: A total of 156 patients (81% male, mean age 60 +/- 10 years), with stable (54%), unstable (40%) angina pectoris or silent ischemia (6%) were enrolled. The target vessel diameter was 2.94 +/- 0.54 mm. The minimal lumen diameter pre, post and at follow-up was 1.04 +/- 0.32 mm, 2.64 +/- 0.42 mm and 1.88 +/- 0.63 mm, respectively. Restenosis rate according to the >50% diameter stenosis criterion at six month follow-up was 19% (26/136). At 12 months, the event-free survival rate was 83% (two deaths, one Q-wave and three non-Q-wave myocardial infarctions, four bypass surgery and 17 target lesion revascularizations), while 87% of the patients were free of angina pectoris. CONCLUSION: the outcome of the FINESS-II trial is comparable to those observed in previous stent trials

  17. Rescue Stenting in Endovascular Treatment of Acutely Ruptured Cerebral Aneurysms

    PubMed Central

    Mahmoud, M.

    2013-01-01

    Summary Thromboembolic events and major artery occlusion following cerebral aneurysm coiling may lead to serious complications and even death if not treated. The use of an intracranial stent in the setting of subarachnoid hemorrhage (SAH) is risky due to the need for antiplatelet therapy. However in some conditions it could be an effective solution for this major problem. This study describes a revascularization technique using a Solitaire stent for treatment of anterior cerebral artery (ACA) occlusion following coiling of anterior communicating artery (Acom) aneurysms. Three cases of ruptured Acom aneurysms treated during the course of SAH underwent unplanned deployment of an intracranial stent. Complete occlusion of the ACA at the origin of the A2 segment developed during or shortly after coiling. Emergent CT brain scan was done in two cases to exclude rebleeding. Follow-up CT or MRI scans were performed 24 hours after stenting. Technical success was achieved in all cases. Complete revascularization of the Acom was achieved post stent deployment (TIMI grade 3). Time from onset of symptoms to full revascularization in the three cases was 35 minutes, one hour 50 minutes and two hours 40 minutes respectively. No intracranial bleeding occurred in any case following the procedure. No neurological changes occurred in case 1; mild neurological and radiological changes occurred in cases 2 and 3. Deployment of an intracranial stent achieved complete revascularization of the occluded Acom. Its use in a context of SAH is relatively risky but the technique resulted in a significant improvement of symptoms following flow restoration and probably helped prevent symptoms worsening, major disability or even death. A study on a larger patient sample with long-term follow-up will be of value. PMID:23472719

  18. Modification of an endovascular stent graft for abdominal aortic aneurysm

    NASA Astrophysics Data System (ADS)

    Moloye, Olajompo Busola

    Endovascular surgery is currently used to treat abdominal aortic aneurysms (AAA). A stent graft is deployed to exclude blood flow from the aneurysm sac. It is an effective procedure used in preventing aneurysm rupture, with reduced patient morbidity and mortality compared to open surgical repair. Migration and leakage around the device ("endoleak") due to poor sealing of the stent graft to the aorta have raised concerns about the long-term durability of endovascular repair. A preliminary study of cell migration and proliferation is presented as a prelude to a more extensive in vivo testing. A method to enhance the biological seal between the stent graft and the aorta is proposed to eliminate this problem. This can be achieved by impregnating the stent graft with 50/50 poly (DL-lactide co glycolic acid) (PLGA) and growth factors such as basic fibroblast growth factor (bFGF) or connective tissue growth factor (CTGF), at the proximal and distal ends. It is hypothesized that as PLGA degrades it will release the growth factors that will promote proliferation and migration of aortic smooth muscle cells to the coated site, leading to a natural seal between the aorta and the stent graft. In addition, growth factor release should promote smooth muscle cell (SMC) contraction that will help keep the stent graft in place at the proximal and distal ends. It is shown that a statistically significant effect of increased cell proliferation and migration is observed for CTGF release. Less of an effect is noted for bFGF or just the PLGA. The effect is estimated to be large enough to be clinically significant in a future animal study. The long term goal of this study is to reduce migration encounter after graft deployment and to reduce secondary interventions of EVAR especially for older patients who are unfit for open surgical treatment.

  19. Ketoprofen-eluting biodegradable ureteral stents by CO2 impregnation: In vitro study.

    PubMed

    Barros, Alexandre A; Oliveira, Carlos; Reis, Rui L; Lima, Estevão; Duarte, Ana Rita C

    2015-11-30

    Ureteral stents are indispensable tools in urologic practice. The main complications associated with ureteral stents are dislocation, infection, pain and encrustation. Biodegradable ureteral stents are one of the most attractive designs with the potential to eliminate several complications associated with the stenting procedure. In this work we hypothesize the impregnation of ketoprofen, by CO2-impregnation in a patented biodegradable ureteral stent previously developed in our group. The biodegradable ureteral stents with each formulation: alginate-based, gellan gum-based were impregnated with ketoprofen and the impregnation conditions tested were 100 bar, 2 h and three different temperatures (35 °C, 40 °C and 50 °C). The impregnation was confirmed by FTIR and DSC demonstrated the amorphization of the drug upon impregnation. The in vitro elution profile in artificial urine solution (AUS) during degradation of a biodegradable ureteral stent loaded with ketoprofen was evaluated. According to the kinetics results these systems have shown to be very promising for the release ketoprofen in the first 72 h, which is the necessary time for anti-inflammatory delivery after the surgical procedure. The in vitro release studied revealed an influence of the temperature on the impregnation yield, with a higher impregnation yield at 40 °C. Higher yields were also obtained for gellan gum-based stents. The non-cytotoxicity characteristic of the developed ketoprofen-eluting biodegradable ureteral stents was evaluated in L929 cell line by MTS assay which demonstrated the feasibility of this product as a medical device.

  20. Vascular gene transfer from metallic stent surfaces using adenoviral vectors tethered through hydrolysable cross-linkers.

    PubMed

    Fishbein, Ilia; Forbes, Scott P; Adamo, Richard F; Chorny, Michael; Levy, Robert J; Alferiev, Ivan S

    2014-08-12

    In-stent restenosis presents a major complication of stent-based revascularization procedures widely used to re-establish blood flow through critically narrowed segments of coronary and peripheral arteries. Endovascular stents capable of tunable release of genes with anti-restenotic activity may present an alternative strategy to presently used drug-eluting stents. In order to attain clinical translation, gene-eluting stents must exhibit predictable kinetics of stent-immobilized gene vector release and site-specific transduction of vasculature, while avoiding an excessive inflammatory response typically associated with the polymer coatings used for physical entrapment of the vector. This paper describes a detailed methodology for coatless tethering of adenoviral gene vectors to stents based on a reversible binding of the adenoviral particles to polyallylamine bisphosphonate (PABT)-modified stainless steel surface via hydrolysable cross-linkers (HC). A family of bifunctional (amine- and thiol-reactive) HC with an average t1/2 of the in-chain ester hydrolysis ranging between 5 and 50 days were used to link the vector with the stent. The vector immobilization procedure is typically carried out within 9 hr and consists of several steps: 1) incubation of the metal samples in an aqueous solution of PABT (4 hr); 2) deprotection of thiol groups installed in PABT with tris(2-carboxyethyl) phosphine (20 min); 3) expansion of thiol reactive capacity of the metal surface by reacting the samples with polyethyleneimine derivatized with pyridyldithio (PDT) groups (2 hr); 4) conversion of PDT groups to thiols with dithiothreitol (10 min); 5) modification of adenoviruses with HC (1 hr); 6) purification of modified adenoviral particles by size-exclusion column chromatography (15 min) and 7) immobilization of thiol-reactive adenoviral particles on the thiolated steel surface (1 hr). This technique has wide potential applicability beyond stents, by facilitating surface engineering of

  1. Colorectal Stents: Current Status

    PubMed Central

    Lee, Jeong-Mi

    2015-01-01

    A self-expandable metal stent (SEMS) is an effective and safe method for the decompression of colon obstruction. Based on recent evidence, colorectal SEMS is now recommended for the palliation of patients with colonic obstruction from incurable colorectal cancer or extracolonic malignancy and also as a bridge to surgery in those who are a high surgical risk. Prophylactic SEMS insertion in patients with no obstruction symptoms is not recommended. Most colorectal SEMS are inserted endoscopically under fluoroscopic guidance. The technical and clinical success rates of colorectal SEMS are high, and the complication rate is acceptable. Advances in this technology will make the insertion of colorectal SEMS better and may expand the indications of colorectal SEMS in the future. PMID:26064818

  2. Intra-channel stent release technique for fluoroless endoscopic ultrasound-guided lumen-apposing metal stent placement: changing the paradigm

    PubMed Central

    Anderloni, Andrea; Attili, Fabia; Carrara, Silvia; Galasso, Domenico; Di Leo, Milena; Costamagna, Guido; Repici, Alessandro; Kunda, Rastislav; Larghi, Alberto

    2017-01-01

    Background Recently, a novel lumen-apposing fully covered self-expanding metal stent (LA-FCSEMS) mounted on an electrocautery-enhanced delivery system has been developed to perform endoscopic ultrasound (EUS)-guided transluminal drainage. From early experience, however, release of the proximal flange of the stent has mostly been done using endoscopic view guidance to ensure proper positioning. Aim We describe a new technique that we have named the Intra-Channel Stent Release Technique (ICSRT) to perform stent placement under complete EUS control, without the use of either fluoroscopic or endoscopic views. Material and methods Data on all consecutive patients who underwent EUS-guided drainage using the new ICSRT between June 2014 and April 2016 were retrospectively retrieved from two institution databases. All EUS procedures were performed by experienced endoscopists with the patient under conscious or deep sedation. The total procedure and stent deployment time, and adverse events related to stent positioning with the ICSRT were evaluated. Results One hundred consecutive patients (51 women; mean age ± SD, 66 ± 15.2 years, range 34 – 95) underwent EUS-guided transluminal drainage with the Hot AXIOS™ device using the new ICSRT. The procedure was technically successful in all but one patient (1 %). The mean total procedural time was 21.9 minutes (range 7 – 50), while the mean time for stent placement was 3.2 minutes (range 1 – 15). No major adverse events occurred. Discussion The ICSRT has been used to deploy the newly developed lumen-apposing FCSEMS under complete EUS guidance without fluoroscopic and/or endoscopic assistance. The technique appears to be safe and highly effective and should be learned by all interventional endosonographers in order to be able to perform drainage in all clinical scenarios.

  3. Mechanical Interaction of an Expanding Coiled Stent with a Plaque-Containing Arterial Wall: A Finite Element Analysis.

    PubMed

    Welch, Tré R; Eberhart, Robert C; Banerjee, Subhash; Chuong, Cheng-Jen

    2016-03-01

    Wall injury is observed during stent expansion within atherosclerotic arteries, related in part to stimulation of the inflammatory process. Wall stress and strain induced by stent expansion can be closely examined by finite element analysis (FEA), thus shedding light on procedure-induced sources of inflammation. The purpose of this work was to use FEA to examine the interaction of a coiled polymer stent with a plaque-containing arterial wall during stent expansion. An asymmetric fibrotic plaque-containing arterial wall model was created from intravascular ultrasound (IVUS) images of a diseased artery. A 3D model for a coil stent at unexpanded state was generated in SolidWorks. They were imported into ANSYS for FEA of combined stent expansion and fibrotic plaque-distortion. We simulated the stent expansion in the plaqued lumen by increasing balloon pressure from 0 to 12 atm in 1 atm step. At increasing pressure, we examined how the expanding stent exerts forces on the fibrotic plaque and vascular wall components, and how the latter collectively resist and balance the expansive forces from the stent. Results show the expanding coiled stent creates high stresses within the plaque and the surrounding fibrotic capsule. Lower stresses were observed in adjacent medial and adventitial layers. High principal strains were observed in plaque and fibrotic capsule. The results suggest fibrotic capsule rupture might occur at localized regions. The FEA/IVUS method can be adapted for routine examination of the effects of the expansion of selected furled stents against IVUS-reconstructed diseased vessels, to improve stent deployment practices.

  4. Percutaneous cholangioscopy in obstructed biliary metal stents

    SciTech Connect

    Hausegger, Klaus A.; Mischinger, Hans J.; Karaic, Radenko; Klein, Guenther E.; Kugler, Cristian; Kern, Robert; Uggowitzer, Martin; Szolar, Dieter

    1997-05-15

    Purpose. To reevaluate the reasons for the occlusion of self-expanding biliary metal stents, on the basis of cholangioscopic findings. Methods. Percutaneous transhepatic cholangioscopy (PTCS) was performed in 15 patients with obstructed biliary Wallstents. The reason for stent insertion was a malignant obstruction in 14 patients; 1 had a benign biliary stricture. Conventional noncovered stents had been inserted in 12 patients; in 3 cases a polyurethane-covered prototype Wallstent had been used. Stent occlusions occurred after 1-55 months. PTCS was performed with a 2.3-mm endoscope through an 11 Fr sheath. Biopsies were taken via the working channel of the endoscope. Results. In all patients with noncovered stents the inner surface of the stent was highly irregular with seaweed-like protrusions (biopsy-proven granulation tissue). Stent incorporation varied from absent (n=1) to subtotal (n=8), but was always incomplete, no matter how long the stent had been in place. Tumor ingrowth was histologically proven in 2 patients. One patient had a large occluding concrement at the proximal end of the stent. In patients with covered stents, the inner surface appeared more regular; however, viable granulation tissue was found inside two stents and tumor ingrowth in one of them. Conclusion. PTCS showed that incorporation of the stent is virtually always incomplete. The factors contributing most to stent occlusion are the buildup of granulation tissue, bile sludge, and tumor overgrowth. Stone formation and tumor ingrowth can also be important, although less common causes of occlusion. A polyurethane stent covering could not prevent tumor ingrowth in one patient and the buildup of viable granulation tissue inside the stent in two further patients; mean stent patency in the three patients with such a stent was 3 months.

  5. Randomized clinical trial comparing abluminal biodegradable polymer sirolimus-eluting stents with durable polymer sirolimus-eluting stents

    PubMed Central

    Zhang, Haijun; Wang, Xiangfei; Deng, Wei; Wang, Shenguo; Ge, Junbo; Toft, Egon

    2016-01-01

    Abstract Background: The biodegradable polymer drug-eluting stents (DES) were developed to improve vascular healing. However, further data and longer-term follow-up are needed to confirm safety and efficacy of these stents. This randomized clinical trial aimed to compare safety and efficacy of 2 sirolimus-eluting stents (SES): Cordimax—a novel abluminal biodegradable polymer SES and Cypher Select—a durable polymer SES, at 9 months angiographic and 5-year clinical follow-up. Methods: We randomized 402 patients with coronary artery disease to percutaneous coronary intervention with Cordimax (n = 202) or Cypher select (n = 200). Angiographic follow-up was performed at 9 months after the index procedure and clinical follow-up annually up to 5 years. The primary endpoint was angiographic in-stent late luminal loss (LLL). Secondary endpoints included angiographic restenosis rate, target vessel revascularization (TVR), and major adverse cardiac events (MACEs; defined as cardiac death, myocardial infarction, or TVR) at 5-year follow-up. Results: Cordimax was noninferior to Cypher select for in-stent LLL (0.25 ± 0.47 vs 0.18 ± 0.49 mm; P = 0.587) and in-stent mean diameter stenosis (22.19 ± 12.21% vs 19.89 ± 10.79%; P = 0.064) at 9 months angiographic follow-up. The MACE rates were not different at 1 year (5.9% vs 4.0%, P = 0.376); however, MACE rates from 2 to 5 years were lower in the Cordimax group (6.8% vs 13.1%; P = 0.039). Conclusion: Abluminal biodegradable polymer SES is noninferior to durable polymer SES at 9-month angiographic and 1-year clinical follow-up. However, MACE rates from 2 to 5 years were less in the abluminal biodegradable polymer group. PMID:27661023

  6. Development of a dynamic in vitro model of a stented blood vessel to evaluate the effects of stent strut material selection and surface coating on smooth muscle cell response

    NASA Astrophysics Data System (ADS)

    Winn, Bradley Huegh

    Cardiovascular disease is the leading cause of mortality in The United States and Europe, accounting for approximately half of all deaths. The most common form of cardiovascular disease is atherosclerosis, which is characterized by the formation of fatty atheromatous plaques that can grow to occlude the vessel lumen, thus causing ischemia distal to the occlusion. This is commonly treated using balloon angioplasty, which is usually done in conjunction with the deployment of a stent. Stent deployment helps hold the vessel open following the local injury caused by balloon inflation and prevents elastic recoil and subsequent negative remodeling. Stenting has been shown to significantly reduce restenosis rates from approximately 20-50% without a stent to about 10-30% with stent deployment. However, restenosis still remains the main cause of long-term stent failure. In basic terms, a balloon angioplasty procedure is a forceful displacement of an atherosclerotic lesion serving to widen the vessel lumen to increase blood flow. This procedure causes stretching of the vessel wall, tears in the atherosclerotic plaques, and general damage to the vessel in turn signaling a complex cascade of thrombosis, inflammation, intimal thickening, and vascular remodeling. Stent deployment also further complicates the immunological response by triggering a foreign body response from the implantation of a biomaterial into the body. When performing an angioplasty procedure, particularly in conjunction with stent deployment, a certain degree of vascular injury is inevitable. However, the initial injury can be further complicated by the body's local reaction to the implanted biomaterial, the severity of which can ultimately dictate the degree of restenosis and subsequently affect procedural success. The proliferative response of VSMCs to the various afore mentioned stimuli results in the formation of often copious amounts of neointimal tissue, generally known as intimal hyperplasia. The

  7. Stent-in-stent through a side hole to prevent biliary metallicstent migration.

    PubMed

    Ridtitid, Wiriyaporn; Rerknimitr, Rungsun; Amornsawadwattana, Surachai; Ponauthai, Yuwadee; Kullavanijaya, Pinit

    2011-03-16

    The covered self-expandable metallic stent (SEMS) has been developed to overcome the problem of tissue in-growth, However, stent migration is a well-known com--plication of covered SEMS placement. Use of a double pigtail stent to lock the movement of the SEMS and prevent migration has been advised by many ex-perts. Unfortunately, in our case this technique led to an in-cidental upward migration of the SEMS. We used APC to create a side hole in the SEMS for plastic stent insertion as stent-in-stent. This led to a successful pre-ven-tion of stent migration.

  8. Two Cases of Immediate Stent Fracture after Zotarolimus-Eluting Stent Implantation

    PubMed Central

    Lee, Pil Hyung; Lee, Seung-Whan; Lee, Jong-Young; Kim, Young-Hak; Lee, Cheol Whan; Park, Duk-Woo; Park, Seong-Wook

    2015-01-01

    Drug-eluting stent (DES) implantation is currently the standard treatment for various types of coronary artery disease. However, previous reports indicate that stent fractures, which usually occur after a period of time from the initial DES implantation, have increased during the DES era; stent fractures can contribute to unfavorable events such as in-stent restenosis and stent thrombosis. In our present report, we describe two cases of zotarolimus-eluting stent fracture: one that was detected six hours after implementation, and the other case that was detected immediately after deployment. Both anatomical and technical risk factors contributed to these unusual cases of immediate stent fracture. PMID:25653706

  9. Cocaine-induced very late stent thrombosis.

    PubMed

    Shah, Priyank; Vasudev, Rahul; Abuarqoub, Ahmad Hisham; Shamoon, Fayez

    2016-10-12

    Cocaine misuse is a known cause of acute coronary syndrome (ACS). Management of these patients has always been a challenge due to medication compliance and eventual risk of stent thrombosis. However, even cocaine misusers who are compliant with dual antiplatelet therapy have been reported to have stent thrombosis. All cases of cocaine-induced stent thrombosis reported in the literature have occurred within first year of stent placement (acute, subacute or late). We report a first case of very late stent thrombosis in a 54-year-old active cocaine misuser who presented with ST segment elevation myocardial infarction, which was successfully managed with percutaneous transluminal coronary angioplasty. A review of all the reported cases of cocaine-induced stent thrombosis is also discussed. Given the high mortality associated with stent thrombosis, treatment option for cocaine misusers presenting with ACS should be conservative when possible. If percutaneous coronary intervention is needed, bare metal stent should be preferred.

  10. Use of Micropatterned Thin Film Nitinol in Carotid Stents to Augment Embolic Protection

    PubMed Central

    Shayan, Mahdis; Jankowitz, Brian T.; Shridhar, Puneeth; Chun, Youngjae

    2016-01-01

    Stenting is an alternative to endarterectomy for the treatment of carotid artery stenosis. However, stenting is associated with a higher risk of procedural stroke secondary to distal thromboembolism. Hybrid stents with a micromesh layer have been proposed to address this complication. We developed a micropatterned thin film nitinol (M-TFN) covered stent designed to prevent thromboembolism during carotid intervention. This innovation may obviate the need or work synergistically with embolic protection devices. The proposed double layered stent is low-profile, thromboresistant, and covered with a M-TFN that can be fabricated with fenestrations of varying geometries and sizes. The M-TFN was created in multiple geometries, dimensions, and porosities by sputter deposition. The efficiency of various M-TFN to capture embolic particles was evaluated in different atherosclerotic carotid stenotic conditions through in vitro tests. The covered stent prevented emboli dislodgement in the range of 70%–96% during 30 min duration tests. In vitro vascular cell growth study results showed that endothelial cell elongation, alignment and growth behaviour silhouettes significantly enhance, specifically on the diamond-shape M-TFN, with the dimensions of 145 µm × 20 µm and a porosity of 32%. Future studies will require in vivo testing. Our results demonstrate that M-TFN has a promising potential for carotid artery stenting. PMID:27983574

  11. Usefulness of biodegradable polydioxanone stents in the treatment of postsurgical colorectal strictures and fistulas.

    PubMed

    Pérez Roldán, F; González Carro, P; Villafáñez García, M C; Aoufi Rabih, S; Legaz Huidobro, M L; Sánchez-Manjavacas Múñoz, N; Roncero García-Escribano, O; Ynfante Ferrús, M; Bernardos Martín, E; Ruiz Carrillo, F

    2012-03-01

    Benign colonic strictures and fistulas are a growing problem presenting most commonly after bowel resection. Standard treatment is with endoscopic bougies or, more usually, balloon dilation. When these approaches are not successful, other solutions are available and different endoscopic and surgical approaches have been used to treat fistulas. We present an additional option--biodegradable stents--for the treatment of colonic strictures and fistulas that have proven refractory to other endoscopic interventions. We analyzed the results from 10 patients with either a postsurgical colorectal stricture (n =7) or rectocutaneous fistula (n =3) treated with the biodegradable SX-ELLA esophageal stent (covered or uncovered). Stents were successfully placed in nine patients, although early migration subsequently occurred in one. Placement was impossible in one patient due to deformity of the area and the fact that the stricture was approximately 30cm from the anus. The fistulas were successfully closed in all patients, although symptoms reappeared in one patient. In the six patients who received stents for strictures, symptoms resolved in five; in the remaining patient, the stent migrated shortly after the endoscopy. Treatment of colonic strictures and rectocutaneous fistulas with biodegradable stents is an effective alternative in the short-to-medium term. The stent does not have to be removed and is subject to very few complications. The drawbacks of this approach are the need to repeat the procedure in some patients and the lack of published series on efficacy.

  12. Evolution of covered stents in the contemporary era: clinical application, materials and manufacturing strategies using nanotechnology.

    PubMed

    Farhatnia, Yasmin; Tan, Aaron; Motiwala, Aamir; Cousins, Brian G; Seifalian, Alexander M

    2013-01-01

    Endovascular stents have revolutionised the field of interventional cardiology. Despite their excellent clinical outcome complications associated with percutaneous stent implantation following the procedure have remained a major drawback in their widespread use. To overcome such limitations, a number of novel endovascular stents have emerged including a covered stent wrapped in a thin membrane sleeve. As well as prevention of complications associated with stenting, covered stents owing to their physical barrier are used as the treatment option of choice for trauma devices during emergency situations and to treat a number of pathological disease states. The aim of this review is to provide the reader with an overall objective outlook in the use of covered stents as a treatment option in a number of vascular complications and addresses their design and materials used in the manufacturing process. In addition, new strategies are highlighted and future prospects with the emergence of novel smart alloys for 3D scaffolds and the use of nanotechnology in the development of nanocomposite materials.

  13. Heating stents with radio frequency energy to prevent tumor ingrowth: modeling and experimental results

    NASA Astrophysics Data System (ADS)

    Ryan, Thomas P.; Lawes, Kate; Goldberg, S. Nahum

    1998-04-01

    Stents are often inserted into internal orifices to treat blockage due to tumor ingrowth. Stents are favored due to their minimally invasive nature, possible avoidance of a surgical procedure, and their ability to palliate surgically non-resectable disease. Because of rapid tumor growth however, a treatment means to prevent overgrowth through the stent and resultant blockage is required. To further this goal, experiments were performed in which a stent was placed in tissue and heated with radiofrequency (RF) energy to coagulate a cylinder of tissue, thereby eradicating viable tissue in the proximity of the stent. Temperatures were measured at the central stent surface and edges over time during a 5 - 10 minute heating in phantom and in fresh tissue. In addition, a finite element model was used to simulate the electric field and temperature distribution. Blood flow was also introduced in the model by evaluating RF application to stents to determine effectiveness of the energy applications. Changing perfusion and tissue electrical conductivity as a function of temperature was applied as the tissue was heated to 100 degree(s)C. Results from the electric field model will be shown as well as the thermal distribution over time from the simulations. Lastly, results from the damage integral will be discussed.

  14. Mechanical properties and biocompatibility of plasma-nitrided laser-cut 316L cardiovascular stents.

    PubMed

    Arslan, Erdem; Iğdil, Mustafa C; Yazici, Hilal; Tamerler, Candan; Bermek, Hakan; Trabzon, Levent

    2008-05-01

    The effect of surface modification of laser-cut 316L cardiovascular stents by low-T plasma nitriding was evaluated in terms of mechanical properties and biocompatibility of the stents. The plasma nitriding was performed at 400, 450 or 500 degrees C using various ratios of nitrogen-hydrogen gas mixtures. The flexibility and radial strength were measured in crimped and expanded state of the stents, respectively. The mechanical properties could be adjusted and improved by plasma nitriding conducted at temperatures lower than 450 degrees C and/or nitrogen content less than 10% in the treatment gas. An osteoblast cell culture model system was utilized to investigate the effect of plasma nitriding of the stents on the biological response towards the stents, using biological criteria such as cell viability, alkaline phosphatase and nitric oxide production. In terms of cell viability and alkaline phosphatase production, the plasma nitriding procedure did not appear to negatively affect the biocompatibility of the 316L steel stents. However, in terms of nitric oxide production that was slightly increased in the presence of the plasma-nitrided stents, an indirect improvement in the biocompatibility could possibly be expected.

  15. Image-based analysis of blood flow modification in stented aneurysms

    NASA Astrophysics Data System (ADS)

    Cebral, Juan; Mut, Fernando; Appanaboyina, Sunil; Löhner, Rainald; Miranda, Carlos; Escrivano, Esteban; Lylyk, Pedro; Putman, Christopher

    2009-02-01

    Currently there is increased interest in the use of stents as flow diverters for the treatment of intracranial aneurysms, especially wide necked aneurysms that are difficult to treat by coil embolization or surgical clipping. This paper presents image-based patient-specific computational models of the hemodynamics in cerebral aneurysms before and after treatment with a stent alone, with the goal of better understanding the hemodynamic effects of these devices and their relation to the outcome of the procedures. Stenting of cerebral aneurysms is a feasible endovascular treatment option for aneurysms with wide necks that are difficult to treat with coils or by surgical clipping. However, this requires stents that are capable of substantially modifying the intra-aneurysmal flow pattern in order to cause thrombosis of the aneurysm. The results presented in this paper show that the studied stent was able to change significantly the hemodynamic characteristics of the aneurysm. In addition, it was shown that patient-specific computational models constructed from medical images are capable of realistically representing the in vivo hemodynamic characteristics observed during conventional angiography examinations before and after stenting. This indicates that these models can be used to better understand the effects of different stent designs and to predict the alteration in the hemodynamic pattern of a given aneurysm produced by a given flow diverter. This is important for improving current design of flow diverting devices and patient treatment plans.

  16. Anatomic Results and Complications of Stent-Assisted Coil Embolization of Intracranial Aneurysms

    PubMed Central

    Kim, S.-R.; Vora, N.; Jovin, T.G.; Gupta, R.; Thomas, A.; Kassam, A.; Lee, K.; Gologorsky, Y.; Jankowitz, B.; Panapitiya, N.; Aleu, A.; Sandhu, E.; Crago, E.; Hricik, A.; Gallek, M.; Horowitz, M.B.

    2008-01-01

    Summary The purpose of this study was to evaluate and report our anatomic results and complications associated with stent-assisted coil embolization of intracranial aneurysms using the Neuroform stent. From September 2003 to August 2007, 127 consecutive patients (ruptured 50, 39.4%; unruptured 77, 60.6%) underwent 129 stent-assisted coil embolization procedures to treat 136 aneurysms at our institution. Anatomic results at follow-up, procedure-related complications, and morbidity/mortality were retrospectively reviewed. Stent deployment was successful in 128 out of 129 procedures (99.2%). Forty-seven patients presented with 53 procedure-related complications (37.0%, 47/127). Thromboembolic events (n=17, 13.4%) were the most common complications, followed by intraoperative rupture (n=8, 6.3%), coil herniation (n=5, 3.9%), and postoperative rupture (n=4, 3.1%). For thromboembolic events, acute intra-procedural in-stent thromboses were observed in two patients and subacute or delayed in-stent thromboses in three patients. Overall mortality rate was 16.5% (21/127) and procedure-related morbidity and mortality rates were 5.5% (7/127) and 8.7% (11/127) retrospectively. Patients with poor grade subarachnoid hemorrhage (Hunt and Hess grade IV or V; 25/127, 19.7%) exhibited 56% (14/25) overall mortality rate and 24% (6/25) procedure-related mortality rate. Immediate angiographic results showed complete occlusion in 31.7% of aneurysms, near-complete occlusion in 45.5%, and partial occlusion in 22.8%. Sixty nine patients in 70 procedures with 77 aneurysms underwent angiographic follow-up at six months or later. Mean follow-up period was 13.7 months (6 to 45 months). Complete occlusion was observed in 57 aneurysms (74.0%) and significant in-stent stenosis was not found. Thromboembolism and intra/postoperative aneurysm ruptures were the most common complications and the main causes of procedure-related morbidity and mortality. Patients with poor grade subarachnoid hemorrhage

  17. Organ transplantation and drug eluting stents: Perioperative challenges

    PubMed Central

    Dalal, Aparna

    2016-01-01

    Patients listed for organ transplant frequently have severe coronary artery disease (CAD), which may be treated with drug eluting stents (DES). Everolimus and zotarolimus eluting stents are commonly used. Newer generation biolimus and novolimus eluting biodegradable stents are becoming increasingly popular. Patients undergoing transplant surgery soon after the placement of DES are at increased risk of stent thrombosis (ST) in the perioperative period. Dual antiplatelet therapy (DAPT) with aspirin and a P2Y12 inhibitor such as clopidogrel, prasugrel and ticagrelor is instated post stenting to decrease the incident of ST. Cangrelor has recently been approved by Food and Drug Administration and can be used as a bridging antiplatelet drug. The risk of ischemia vs bleeding must be considered when discontinuing or continuing DAPT for surgery. Though living donor transplant surgery is an elective procedure and can be optimally timed, cadaveric organ availability is unpredictable, therefore, discontinuation of antiplatelet medication cannot be optimally timed. The type of stent and timing of transplant surgery can be of utmost importance. Many platelet function point of care tests such as Light Transmittance Aggregrometry, Thromboelastography Platelet Mapping, VerifyNow, Multiple Electrode Aggregrometry are used to assess bleeding risk and guide perioperative platelet transfusion. Response to allogenic platelet transfusion to control severe intraoperative bleeding may differ with the antiplatelet drug. In stent thrombosis is an emergency where management with either a drug eluting balloon or a DES has shown superior outcomes. Post-transplant complications often involved stenosis of an important vessel that may need revascularization. DES are now used for endovascular interventions for transplant orthotropic heart CAD, hepatic artery stenosis post liver transplantation, transplant renal artery stenosis following kidney transplantation, etc. Several antiproliferative drugs

  18. Safety and efficacy of self-expandable metallic stents in malignant small bowel obstructions

    PubMed Central

    Tsuboi, Akiyoshi; Kuwai, Toshio; Nishimura, Tomoyuki; Iio, Sumio; Mori, Takeshi; Imagawa, Hiroki; Yamaguchi, Toshiki; Yamaguchi, Atsushi; Kouno, Hirotaka; Kohno, Hiroshi

    2016-01-01

    In this report, we present 3 cases of malignant small bowel obstruction, treated with palliative care using endoscopic self-expandable metallic stent (SEMS) placement, with the aim to identify the safety and efficacy of this procedure. Baseline patient characteristics, procedure methods, procedure time, technical and clinical success rates, complications, and patient outcomes were obtained. All 3 patients had pancreatic cancer with small bowel strictures. One patient received the SEMS using colonoscopy, while the other 2 patients received SEMS placement via double balloon endoscopy using the through-the-overtube technique. The median procedure time was 104 min. The technical and clinical success rates were 100%. Post-treatment, obstructive symptoms in all patients improved, and a low-residue diet could be tolerated. All stents remained within the patients until their deaths. The median overall survival time (stent patency time) was 76 d. SEMS placement is safe and effective as a palliative treatment for malignant small bowel obstruction. PMID:27833393

  19. Acute and long-term outcome after Palmaz-Schatz stenting: analysis from the New Approaches to Coronary Intervention (NACI) registry.

    PubMed

    Carrozza, J P; Schatz, R A; George, C J; Leon, M B; King, S B; Hirshfeld, J W; Curry, R C; Ivanhoe, R J; Buchbinder, M; Cleman, M W; Goldberg, S; Ricci, D; Popma, J J; Safian, R D; Baim, D S

    1997-11-20

    The randomized Stent Restenosis Study (STRESS) and Belgium Netherlands Stent (Benestent) trials established that elective use of Palmaz-Schatz stents (PSSs) in native coronary arteries with de novo lesions is associated with increased procedural success and reduced restenosis. However there are other clinical indications for which stents are commonly used (unplanned use, vein grafts, restenosis lesions) that are not addressed in these studies. From 1990-1992, 688 lesions in 628 patients were treated with PSSs in the New Approaches to Coronary Intervention (NACI) registry. Angiographic core laboratory readings were available for 543 patients (595 lesions, of which 106 were stented for unplanned indications, 239 were in saphenous vein bypass grafts, and 296 were previously treated). The cohort of patients in whom stents were placed for unplanned indications had more women, current smokers, and had a higher incidence of recent myocardial infarction (MI). Patients who underwent stenting of saphenous vein grafts were older, had a higher incidence of diabetes mellitus, unstable angina, prior MI, and congestive heart failure. Lesion success was similar in all cohorts (98%), but procedural success was significantly higher for planned stenting (96% vs 87%; p < 0.01). Predictors of adverse events in-hospital were presence of a significant left main stenosis and stenting for unplanned indication. The incidence of target lesion revascularization by 30 days was significantly higher for patients undergoing unplanned stenting due to a higher risk for stent thrombosis. Recent MI, stenting in native lesion, and small postprocedural minimum lumen diameter independently predicted target lesion revascularization at 30 days. Independent predictors of death, Q-wave myocardial infarction, or target lesion revascularization at 1 year included severe concomitant disease, high risk for surgery, left main disease, stenting in the left main coronary artery, and low postprocedure minimum lumen

  20. Impact of Stent Design on In-Stent Stenosis in a Rabbit Iliac Artery Model

    SciTech Connect

    Sommer, C. M. Grenacher, L.; Stampfl, U.; Arnegger, F. U.; Rehnitz, C.; Thierjung, H.; Stampfl, S.; Berger, I.; Richter, G. M.; Kauczor, H. U.; Radeleff, B. A.

    2010-06-15

    The purpose of this study was to evaluate the impact of stent design on in-stent stenosis in rabbit iliac arteries. Four different types of stent were implanted in rabbit iliac arteries, being different in stent design (crown or wave) and strut thickness (50 or 100 {mu}m). Ten stents of each type were implanted. Each animal received one crown and one wave stent with the same strut thickness. Follow-up was either 12 weeks (n = 10 rabbits) or 24 weeks (n = 10 rabbits). Primary study end points were angiographic and microscopic in-stent stenosis. Secondary study end points were vessel injury, vascular inflammation, and stent endothelialization. Average stent diameter, relative stent overdilation, average and minimal luminal diameter, and relative average and maximum luminal loss were not significantly different. However, a trend to higher relative stent overdilation was recognized in crown stents compared to wave stents. A trend toward higher average and minimal luminal diameter and lower relative average and maximum luminal loss was recognized in crown stents compared to wave stents with a strut thickness of 100 {mu}m. Neointimal height, relative luminal area stenosis, injury score, inflammation score, and endothelialization score were not significantly different. However, a trend toward higher neointimal height was recognized in crown stents compared to wave stents with a strut thickness of 50 {mu}m and a follow-up of 24 weeks. In conclusion, in this study, crown stents seem to trigger neointima. However, the optimized radial force might equalize the theoretically higher tendency for restenosis in crown stents. In this context, also more favorable positive remodeling in crown stents could be important.

  1. Late stent thrombosis after implantation of a sirolimus-eluting stent.

    PubMed

    Kerner, Arthur; Gruberg, Luis; Kapeliovich, Michael; Grenadier, Ehud

    2003-12-01

    Late stent thrombosis in the era of routine high-pressure stent deployment and combined antiplatelet therapy with thienopyridines and aspirin has become a rare but feared complication. We describe a patient with acute myocardial infarction due to late stent thrombosis 6 weeks after deployment of a sirolimus-eluting stent and 2 weeks after the discontinuation of clopidogrel. This is the first report of late thrombosis of a sirolimus-eluting stent.

  2. Fluid mechanics in stented arterial model

    NASA Astrophysics Data System (ADS)

    Bernad, S. I.; Totorean, A.; Bosioc, A.; Crainic, N.; Hudrea, C.; Bernad, E. S.

    2015-12-01

    Local hemodynamic factors are known affect the natural history of the restenosis critically after coronary stenting of atherosclerosis. Stent-induced flows disturbance magnitude dependent directly on the strut design. Strut shape, strut thickness and the distance between consecutive struts have been associated clinically with the with post-intervention clinical outcomes. Hemodynamically favorable designs according to computational modeling can reduced in-stent restenosis after coronary stenting intervention.

  3. Impact of Clinical Trial Results on the Temporal Trends of Carotid Endarterectomy and Stenting From 2002 to 2014

    PubMed Central

    Hussain, Mohamad A.; Mamdani, Muhammad; Tu, Jack V.; Saposnik, Gustavo; Khoushhal, Zeyad; Aljabri, Badr; Verma, Subdoh

    2016-01-01

    Background and Purpose— Randomized trials provide conflicting data for the efficacy of carotid-artery stenting compared with endarterectomy. The purpose of this study was to examine the impact of conflicting clinical trial publications on the utilization rates of carotid revascularization procedures. Methods— We conducted a population-level time-series analysis of all individuals who underwent carotid endarterectomy and stenting in Ontario, Canada (2002–2014). The primary analysis examined temporal changes in the rates of carotid revascularization procedures after publications of major randomized trials. Secondary analyses examined changes in overall and age, sex, carotid-artery symptom, and operator specialty–specific procedure rates. Results— A total of 16 772 patients were studied (14 394 endarterectomy [86%]; 2378 stenting [14%]). The overall rate of carotid revascularization decreased from 6.0 procedures per 100 000 individuals ≥40 years old in April 2002 to 4.3 procedures in the first quarter of 2014 (29% decrease; P<0.001). The rate of endarterectomy decreased by 36% (P<0.001), whereas the rate of carotid-artery stenting increased by 72% (P=0.006). We observed a marked increase (P=0.01) in stenting after publication of the SAPPHIRE trial (Stenting and Angioplasty With Protection in Patients at High Risk for Endarterectomy) in 2004, whereas stenting remained relatively unchanged after subsequent randomized trials published in 2006 (P=0.11) and 2010 (P=0.34). In contrast, endarterectomy decreased after trials published in 2006 (P=0.04) and 2010 (P=0.005). Conclusions— Although the overall rates of carotid revascularization and endarterectomy have fallen since 2002, the rate of carotid-artery stenting has risen since the publication of stenting-favorable SAPPHIRE trial. Subsequent conflicting randomized trials were associated with a decreasing rate of carotid endarterectomy. PMID:27834754

  4. Outcome of intracranial arterial stenting of symptomatic atherosclerotic disease: A single center experience from Saudi Arabia

    PubMed Central

    Said, Youssef Al; Kurdi, Khalil; Baeesa, Saleh S.; Najjar, Ahmed; Almekhlafi, Mohammed; Hassan, Ahmed

    2016-01-01

    Objectives: To present our local experience with intracranial angioplasty and stenting used for the treatment of symptomatic intracranial stenosis to assess its safety, efficacy, and outcome. Methods: This is a retrospective review of all the patients with symptomatic intracranial atherosclerotic disease who underwent endovascular treatment in King Faisal Specialist Hospital and research center, Jeddah, Kingdom of Saudi Arabia from January 2003 to December 2014. Clinical, procedural, and outcome variables were gathered. Results: We identified 22 patients who were referred for stenting of symptomatic intracranial atherosclerotic stenosis. In all but 3, the stents were deployed successfully (86% procedural success rate). The procedure was carried out under conscious sedation in 32%. Excellent flow was restored immediately in all successfully-stented cases. Post procedural strokes occurred in 4 patients (17.4%). One non-neurological death was identified in a patient who suffered a major post procedural stroke (4.3%). Conclusion: Intracranial atherosclerotic disease is not uncommon in our population. Angioplasty and stenting might be a valid option for the treatment of patients with recurrent symptoms despite optimal medical treatment. PMID:27744470

  5. Impact of stent design on the outcome of intervention for carotid bifurcation stenosis.

    PubMed

    Hart, J P; Bosiers, M; Deloose, K; Uflacker, R; Schönholz, C J

    2010-12-01

    Over the past several years, there has been continued significant interest in refinement of patient selection, devices, procedures and protocols in an effort to optimize the outcome of percutaneous intervention for carotid bifurcation stenosis, including: ongoing National Institutes of Health and manufacturer trials and registries; the further refinement of existing devices and emergence of new platforms to attain distal embolic protection; ongoing study of what really constitutes a high-risk carotid surgery or stenting patient; and attention to device characteristics and patient-device matching. Within the latter area, considerable interest has focused on stent characteristics that have the potential to impact short and long-term outcome when compared with other stent design strategies when studied in large series. The stent in carotid artery intervention occupies a unique role in that after the embolic protection system has been removed, it is the main line of defense (in concert with aggressive dual antiplatelet therapy) from embolic and thromboembolic complications that may arise from the newly remodeled plaque after post-stent angioplasty. In this review, we aim to update the current status of efforts to relate stent design strategy to outcome in intervention for extracranial carotid artery disease with a focus primarily on the function of "free cell area" (typically lower with closed-cell stents and higher with open-cell stents) in analyses of outcome in carotid artery stenting. Also, the potential role of closed-cell vs. open-cell stent selection in other reports related to carotid artery stenting outcome or complications is reviewed. Rigorous studies have examined the issue of free cell area and arrived at disparate conclusions. Randomized data on the impact of free cell area and cell design strategy on carotid intervention are presently lacking. However, we believe sufficient data and rationale exist 1) to warrant ongoing study of the impact of stent

  6. 21 CFR 884.3900 - Vaginal stent.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Vaginal stent. 884.3900 Section 884.3900 Food and... OBSTETRICAL AND GYNECOLOGICAL DEVICES Obstetrical and Gynecological Prosthetic Devices § 884.3900 Vaginal stent. (a) Identification. A vaginal stent is a device used to enlarge the vagina by stretching, or...

  7. 21 CFR 884.3900 - Vaginal stent.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Vaginal stent. 884.3900 Section 884.3900 Food and... OBSTETRICAL AND GYNECOLOGICAL DEVICES Obstetrical and Gynecological Prosthetic Devices § 884.3900 Vaginal stent. (a) Identification. A vaginal stent is a device used to enlarge the vagina by stretching, or...

  8. 21 CFR 884.3900 - Vaginal stent.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Vaginal stent. 884.3900 Section 884.3900 Food and... OBSTETRICAL AND GYNECOLOGICAL DEVICES Obstetrical and Gynecological Prosthetic Devices § 884.3900 Vaginal stent. (a) Identification. A vaginal stent is a device used to enlarge the vagina by stretching, or...

  9. 21 CFR 884.3900 - Vaginal stent.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Vaginal stent. 884.3900 Section 884.3900 Food and... OBSTETRICAL AND GYNECOLOGICAL DEVICES Obstetrical and Gynecological Prosthetic Devices § 884.3900 Vaginal stent. (a) Identification. A vaginal stent is a device used to enlarge the vagina by stretching, or...

  10. 21 CFR 884.3900 - Vaginal stent.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Vaginal stent. 884.3900 Section 884.3900 Food and... OBSTETRICAL AND GYNECOLOGICAL DEVICES Obstetrical and Gynecological Prosthetic Devices § 884.3900 Vaginal stent. (a) Identification. A vaginal stent is a device used to enlarge the vagina by stretching, or...

  11. Refining stent technologies for femoral interventions.

    PubMed

    Bosiers, M; Deloose, K; Callaert, J; Maene, L; Keirse, K; Verbist, J; Peeters, P

    2012-08-01

    Stents were created as a mechanical scaffold to prevent vessel recoil and luminal renarrowing after percutaneous transluminal angioplasty (PTA). In femoropopliteal arteries, indication for stent implantation remains a topic much debated on, especially in long lesion configurations. Ever since the first stents were introduced on the market, in-stent restenosis (ISR) has been an important issue. The evolution in stent design has known a major progression in the last decades from the first generation of stents, plagued with high fracture rates and low primary patency rates, to the design of newer stents to tackle these outcomes. More flexible and longer stents decreased the high fracture rates and drug-eluting stents offered a solution to the restenosis rates by local drug application. The difficult recrossibility of the lesion because of the presence of a permanent vascular scaffold is an obstacle that the drug-coated balloon (DCB) overcomes. Future perspectives in the treatment of femoropopliteal lesions are found in the bioresorbable stent implantation. The bioresorbable stent combines the advantages of a drug-eluting scaffolding stent without the remainder of a foreign object in the long-term. Further investigations in this area will eventually evolve in the creation of a superior endovascular treatment modality with high long-term patency rates and minimal detriments.

  12. Dacron Graft Aneurysm Treated by Endovascular Stent-Graft

    SciTech Connect

    Ofer, Amos; Nitecki, Samy; Hoffman, Aaron; Engel, Ahuva

    2001-01-15

    A 72-year old man who underwent aorto-bifemoral bypass with insertion of a Dacron graft 18 years previously presented with an aneurysm in the left limb of his graft. Angiography also demonstrated a bilateral occlusion of the popliteal arteries. Computed tomography (CT) angiography was performed and showed a localized dilation of 3 cm in the left limb of the graft, which had a diameter of 14 mm throughout. In view of the technical difficulties of a surgical procedure, an endovascular stent was considered. Through a left femoral arteriotomy, a stent graft was inserted and deployed in the left limb of the graft. This resulted in total exclusion of the Dacron graft aneurysm. To the best of our knowledge, this is the first report of such a procedure.

  13. Biodegradable stents: they do their job and disappear.

    PubMed

    Waksman, Ron

    2006-02-01

    Despite the development and progression of metallic stents, many concerns still remain because of their permanent nature. Although metallic stents are effective in preventing recoil and late restenosis after coronary angioplasty, they continue to have limitations such as stent thrombosis and mismatch of the stent to the vessel size. Thus, the concept of bioabsorbable stents has emerged as an alternative to permanent metal stents. This review will outline concepts, material designs, preclinical, and initial clinical experimental studies with bioabsorbable stents.

  14. Renal Stenting from the Radial Artery: A Novel Approach

    SciTech Connect

    Kessel, David O.; Robertson, Iain; Taylor, Edward J.; Patel, Jai V.

    2003-04-15

    Purpose: To describe the technique and feasibility of renal artery angioplasty and stenting from the radial artery. Methods: A series of 19 patients were evaluated for transradial renal artery intervention. Procedures were performed using carbon dioxide gas (CO{sub 2}) as the preferred angiographic contrast agent. Intervention was performed through a 5 Fr radial artery sheath using low-profile balloons and balloon-expandable stents. Results: Nineteen patients with 26 stenosed renal arteries were considered for treatment via the radial route. A negative Allen's test precluded radial puncture in two (11%). In one patient the descending aorta could not be catheterized. Stenting from the radial route was successful in 22 renal arteries in 16 patients. On an intention-to-treat basis 16 of the 19 (84%) were treatable from the radial route. In the 17 patients with radial access technical success was 94% (16 of 17) patients and 91% (21 of 23) of renal arteries. One patient experienced a cerebrovascular event during intervention. Conclusion: Transradial renal artery intervention is technically feasible using low-profile angioplasty balloons and stents.This route offers advantages in renal arteries with a caudal angulation and in patients with diseases or tortuous iliac arteries.

  15. Automatic detection of coronary stent struts in intravascular OCT imaging

    NASA Astrophysics Data System (ADS)

    Tung, Kai Pin; Shi, Wen Zhe; Pizarro, Luis; Tsujioka, Hiroto; Wang, Hai-Yan; Guerrero, Ricardo; De Silva, Ranil; Edwards, Philip E.; Rueckert, Daniel

    2012-03-01

    Optical coherence tomography (OCT) is a light-based, high resolution imaging technique to guide stent deployment procedure for stenosis. OCT can accurately differentiate the most superficial layers of the vessel wall as well as stent struts and the vascular tissue surrounding them. In this paper, we automatically detect the struts of coronary stents present in OCT sequences. We propose a novel method to detect the strut shadow zone and accurately segment and reconstruct the strut in 3D. The estimation of the position of the strut shadow zone is the key requirement which enables the strut segmentation. After identification of the shadow zone we use probability map to estimate stent strut positions. This method can be applied to cross-sectional OCT images to detect the struts. Validation is performed using simulated data as well as in four in-vivo OCT sequences and the accuracy of strut detection is over 90%. The comparison against manual expert segmentation demonstrates that the proposed strut identification is robust and accurate.

  16. Clinical outcomes following stent implantation in internal mammary artery grafts.

    PubMed

    Sharma, Arvind K; McGlynn, Scott; Apple, Sue; Pinnow, Ellen; Canos, Daniel A; Gevorkian, Natalie; Tebeica, Mihaela; Gruberg, Luis; Pichard, Augusto D; Lindsay, Joseph

    2003-08-01

    We evaluated our experience with percutaneous coronary intervention (PCI) of internal mammary artery (IMA) grafts. From the institution's database we identified 288 patients with 311 IMA lesions. Of these, 82 (26.4%) had stents placed during PCI. Angiographic success was 92%. Mortality at 1 month was 1.7%, myocardial infarction (MI) 15.7%, and target lesion revascularization (TLR) 0.4%. Cumulative 1-year event rates were mortality 6.4%, MI 20.4%, and TLR 8.0%. TLR rates were significantly higher in the stented lesions than lesions treated with angioplasty alone (19.2% vs. 4.9%; P = 0.004). The higher TLR rate in stented lesions was most apparent at the anastomotic site (25.0% vs. 4.2%; P = 0.006). Percutaneous revascularization of IMA grafts can be performed safely with high procedural success and excellent short- and long-term results. Stenting, particularly at the anastomotic site, was associated with significantly greater rates of TLR than angioplasty alone.

  17. A fully covered self-expandable metal stent anchored by a 10-Fr double pigtail plastic stent: an effective anti-migration technique

    PubMed Central

    Katsinelos, Panagiotis; Lazaraki, Georgia; Gkagkalis, Stergios; Chatzimavroudis, Grigoris; Anastasiadou, Kiriaki; Georgakis, Nikos; Giouleme, Olga; Zavos, Christos; Kountouras, Jannis

    2017-01-01

    Background Fully covered self-expandable metal stents (FCSEMS) have been used successfully in the treatment of malignant and benign biliary strictures. However, stent migration is a major complication. We investigated the efficacy of anchoring FCSEMS with a 10-Fr double-pigtail plastic stent to prevent migration in patients with biliary strictures. Methods Between January 2012 and May 2013, 10 patients with malignant biliary strictures and one patient with a suprapapillary benign biliary stenosis were enrolled in the study. The primary endpoint of the study was to record the migration rate of FCSEMS. Results The placement of FCSEMSs and the anchoring with a 10-Fr double-pigtail plastic stent were successful in all patients. During a median follow-up period of eight months, proximal or distal migration of FCSEMS was not observed. No procedural complications related to the placement of FCSEMS and/or the anchoring plastic stent were recorded. Conclusions The placement of an anchoring 10-Fr double-pigtail stent is a simple and effective anti-migration technique for FCSEMS in patients with malignant biliary strictures. PMID:28042247

  18. Prospective, randomized study of one, two, or three trabecular bypass stents in open-angle glaucoma subjects on topical hypotensive medication

    PubMed Central

    Katz, L Jay; Erb, Carl; Carceller, Guillamet Amadeu; Fea, Antonio M; Voskanyan, Lilit; Wells, Jeffrey M; Giamporcaro, Jane Ellen

    2015-01-01

    Purpose To assess the safety and efficacy of one, two, or three trabecular microbypass stents in eyes with primary open-angle glaucoma (OAG) not controlled on ocular hypotensive medication. A total of 119 subjects were followed for 18 months postoperatively. Materials and methods Subjects with medicated intraocular pressure (IOP) 18–30 mmHg and postmedication-washout baseline IOP 22–38 mmHg were randomized to implantation of one, two, or three stents. Ocular hypotensive medication was to be used if postoperative IOP exceeded 18 mmHg. Results A total of 38 subjects were implanted with one stent, 41 subjects with two stents, and 40 subjects with three stents. Both month 12 IOP reduction ≥20% without ocular hypotensive medication vs baseline unmedicated IOP and month 12 unmedicated IOP ≤18 mmHg were achieved by 89.2%, 90.2%, and 92.1% of one-, two-, and three-stent eyes, respectively. Furthermore, 64.9%, 85.4%, and 92.1% of the three respective groups achieved unmedicated IOP ≤15 mmHg. Over the 18-month follow-up period, medication was required in seven one-stent subjects, four two-stent subjects, and three three-stent subjects. At 18 months, mean unmedicated IOP was 15.9±0.9 mmHg in one-stent subjects, 14.1±1.0 mmHg in two-stent subjects, and 12.2±1.1 mmHg in three-stent subjects. Month 18 IOP reduction was significantly greater (P<0.001) with implantation of each additional stent, with mean differences in reduction of 1.84 mmHg (95% confidence interval 0.96–2.73) for three-stent vs two-stent groups and 1.73 mmHg (95% confidence interval 0.83–2.64) for two-stent vs one-stent groups. Adverse events through 18 months were limited to cataract progression with best-corrected visual acuity loss and subsequent cataract surgery. Conclusion In this series, implantation of each additional stent resulted in significantly greater IOP reduction with reduced medication use. Titratability of stents as a sole procedure was shown to be effective and safe, with

  19. Enhancing Stent Effectiveness with Nanofeatures

    PubMed Central

    Bassous, Nicole; Cooke, John P.; Webster, Thomas J.

    2016-01-01

    Drug-eluting stents are an effective therapy for symptomatic arterial obstructions, substantially reducing the incidence of restenosis by suppressing the migration and proliferation of vascular smooth muscle cells into the intima. However, current drug-eluting stents also inhibit the growth of endothelial cells, which are required to cover the vascular stent to reduce an excessive inflammatory response. As a result, the endothelial lining of the lumen is not regenerated. Since the loss of this homeostatic monolayer increases the risk of thrombosis, patients with drug-eluting stents require long-term antithrombotic therapy. Thus, there is a need for improved devices with enhanced effectiveness and physiological compatibility towards endothelial cells. Current developments in nanomaterials may enhance the function of commercially available vascular devices. In particular, modified design schemes might incorporate nanopatterns or nanoparticle-eluting features that reduce restenosis and enhance re-endothelialization. The intent of this review is to discuss emerging nanotechnologies that will improve the performance of vascular stents. PMID:27826371

  20. Non-polymeric coatings to control drug release from metallic coronary stents

    NASA Astrophysics Data System (ADS)

    Gupta, Celia Edith Macias

    Percutaneous transluminal coronary angiography (PTCA) is a procedure used to re-open narrowed coronary arteries. During PTCA, a coronary stent is expanded inside a diseased vessel and serves as a scaffold to keep the artery open. The major drawback of stenting is restenosis---a re-narrowing of the vessel resulting from the hyperproliferation of smooth muscle cells. Drug eluting stents (DES) reduce the rate of restenosis compared to bare metal stents. Paclitaxel (PAT) is commonly used in DES for its ability to prevent restenosis. However, DES have been associated with thrombosis due to the polymer carrier that controls drug delivery. Therefore, there is a need to change the drug delivery mechanisms to eliminate the need of polymers. The goal of this dissertation is to develop a novel polymer-free drug eluting stent that controls drug release using nanoscale metal coatings. The coating was designed to release PAT as the metal slowly degrades in biological conditions. Once all the Paclitaxel has eluted from the surface, the coating will continue to degrade until the final result is a bare metal stent. The results of this study include a novel non-polymeric drug delivery system using nanoscale coatings that release Paclitaxel at a rate similar to commercial stents, as well as the biocompatibility and efficacy of these coatings. The non-polymeric drug delivery system described here achieved a Paclitaxel release profile equivalent to clinically available Paclitaxel-eluting stents and effectively inhibits smooth muscle cell proliferation, thereby completely eliminating the need for polymers to control drug release from coronary stents.

  1. Efficacy of multiple biliary stenting for refractory benign biliary strictures due to chronic calcifying pancreatitis

    PubMed Central

    Ohyama, Hiroshi; Mikata, Rintaro; Ishihara, Takeshi; Sakai, Yuji; Sugiyama, Harutoshi; Yasui, Shin; Tsuyuguchi, Toshio

    2017-01-01

    AIM To investigate endoscopic therapy efficacy for refractory benign biliary strictures (BBS) with multiple biliary stenting and clarify predictors. METHODS Ten consecutive patients with stones in the pancreatic head and BBS due to chronic pancreatitis who underwent endoscopic therapy were evaluated. Endoscopic insertion of a single stent failed in all patients. We used plastic stents (7F, 8.5F, and 10F) and increased stents at intervals of 2 or 3 mo. Stents were removed approximately 1 year after initial stenting. BBS and common bile duct (CBD) diameter were evaluated using cholangiography. Patients were followed for ≥ 6 mo after therapy, interviewed for cholestasis symptoms, and underwent liver function testing every visit. Patients with complete and incomplete stricture dilations were compared. RESULTS Endoscopic therapy was completed in 8 (80%) patients, whereas 2 (20%) patients could not continue therapy because of severe acute cholangitis and abdominal abscess, respectively. The mean number of stents was 4.1 ± 1.2. In two (20%) patients, BBS did not improve; thus, a biliary stent was inserted. BBS improved in six (60%) patients. CBD diameter improved more significantly in the complete group than in the incomplete group (6.1 ± 1.8 mm vs 13.7 ± 2.2 mm, respectively, P = 0.010). Stricture length was significantly associated with complete stricture dilation (complete group; 20.5 ± 3.0 mm, incomplete group; 29.0 ± 5.1 mm, P = 0.011). Acute cholangitis did not recur during the mean follow-up period of 20.6 ± 7.3 mo. CONCLUSION Sequential endoscopic insertion of multiple stents is effective for refractory BBS caused by chronic calcifying pancreatitis. BBS length calculation can improve patient selection procedure for therapy. PMID:28101303

  2. Risk factors for the development of restenosis following stent implantation of venous bypass grafts

    PubMed Central

    Heidland, U; Heintzen, M; Michel, C; Strauer, B

    2001-01-01

    OBJECTIVE—To analyse the variables involved in the high restenosis rate following stent implantation in coronary artery bypass grafts.
DESIGN—A retrospective analysis of a consecutive group of patients attending a tertiary centre.
PATIENTS—The long term angiographic outcome of 219 stent implantations for individual lesions performed in 191 patients was investigated. Multivariate analysis correlated clinical, procedural, and angiographic variables with the incidence of angiographic restenosis, defined as diameter stenosis > 50% at follow up.
RESULTS—Angiographic restenosis was observed in 34% of lesions treated. Multiple logistic regression analysis defined diabetes mellitus (odds ratio 6.91, 95% confidence interval (CI) 2.43 to 9.69), graft recanalisation (2.89, 95% CI 1.18 to 6.63), lesion at the aortic anastomosis (6.98, 95% CI 2.77 to 21.31), lesion at the coronary anastomosis (3.01, 95% CI 1.19 to 7.69), high diameter stenosis after stent placement (7.21, 95% CI 2.66 to 16.81), placement of long stents (2.73, 95% CI 1.09 to 7.39), and implantation of more than one stent (7.31, 95% CI 2.08 to 19.96) as independent predictors of graft in-stent restenosis.
CONCLUSIONS—There appears to be a specific risk factor constellation contributing to the high restenosis rate following stent implantation in venous bypass grafts. Critical consideration of these variables may help identify patients who are poor candidates for stent implantation and who may benefit from a different approach.


Keywords: coronary artery bypass graft; stent; restenosis PMID:11179274

  3. Changes in the Distribution of Hepatic Arterial Blood Flow Following TIPS with Uncovered Stent and Stent-Graft: An Experimental Study

    SciTech Connect

    Keussen, Inger; Song, Ho-Young; Bajc, Marika; Cwikiel, Wojciech

    2002-08-15

    Purpose: To evaluate changes in distribution of hepatic arterial blood flow in the liver following insertion of an uncovered stent and subsequently a stent-graft in the transjugular intrahepatic portosystemic shunt (TIPS) channel.Methods: The experiments were performed in eight healthy pigs under general anesthesia. In a pilot study in one pig, scintigraphic evaluation of arterial perfusion to the liver was done before and after inflation of a balloon in the right hepatic vein. In the other pigs, outflow from the right liver vein was checked repeatedly by contrast injection through a percutaneously inserted catheter. The arterial perfusion through the liver was examined by scintigraphy, following selective injection of macro-aggregate of 99Tcm-labeled human serum albumin 99Tcm-HSA) into the hepatic artery. This examination was done before and after creation of a TIPS with an uncovered stent and subsequently after insertion of a covered stent-graft into the cranial portion of the shunt channel. Results: In the pilot study changes in the arterial perfusion to the liver were easily detectable by scintigraphy. One pig died during the procedure and another pig was excluded due to dislodgement of the hepatic artery catheter. The inserted covered stent obstructed venous outflow from part of the right liver lobe. The 99Tcm-HSA activity in this part remained unchanged after TIPS creation with an uncovered stent. A reduction in activity was seen after insertion of a stent-graft (p0.06).Conclusion: The distribution of the hepaticarterial blood flow is affected by creation of a TIPS with a stent-graft, in the experimental pig model.

  4. Stenting of the arterial duct: a new approach to palliation for pulmonary atresia.

    PubMed Central

    Gibbs, J L; Rothman, M T; Rees, M R; Parsons, J M; Blackburn, M E; Ruiz, C E

    1992-01-01

    OBJECTIVE--To assess the possibility of maintaining ductal patency in neonates with complex pulmonary atresia by percutaneous implantation of balloon expandable stents. PATIENTS--Two duct-dependent neonates with long segment pulmonary atresia, right sided aortic arch, and left sided arterial duct. RESULTS--Stents with final diameter of 3.5 or 4 mm and initial length of 7 or 15 mm were successfully positioned in the arterial duct. Two stents were required in one child and four in the other in order to stent the entire length of the duct. After the procedures the ducts remained widely patent and arterial oxygen saturations remained above 80%. Complications of the procedures included perforation of a peripheral pulmonary artery and cardiac perforation, both caused by guide wire manipulation. Both babies died suddenly, one at five weeks, and the other at nine days after successful stenting of the duct. Both ducts were patent at necropsy; the exact cause of one death was not clearly defined, but the second seemed to be caused by pneumococcal septicaemia. CONCLUSIONS--Stenting of the arterial duct is technically feasible. It provides adequate palliation for neonates with pulmonary atresia at least in the short term and it seems to result in balanced, central perfusion of both pulmonary arteries. This preliminary report suggests that this previously untried technique may prove to be a promising and attractive alternative to neonatal aortopulmonary shunt operation. Images PMID:1372815

  5. Clinical Results of Percutaneous Transluminal Angioplasty and Stenting for Intracranial Vertebrobasilar Atherosclerotic Stenoses and Occlusions

    PubMed Central

    Tsuura, M.; Terada, T.; Masuo, O.; Tsumoto, T.; Yamaga, H.; Itakura, T.; Matsumoto, H.; Hyoutani, G.; Hayashi, S.

    2004-01-01

    Summary Eighteen patients with intracranial vertebrobasilar stenosis and occlusion were treated by PTA or stenting. In 11 of 18 cases, only PTA was performed and in seven of 18 cases, we used stents. The mean stenosis before and after PTA/stenting was 82.8% and 22.3%, respectively. In 11 cases of PTA only, the stenotic rate decreased from 81.8% to 29.6%, while 85.0% of the stenotic rate remarkably reduced to 6.0% in seven cases of stenting. The 30 days morbidity and 30 days mortality rate were 5.5% and 5.5%, respectively. There was only one haemorrhagic complication (cerebellar haemorrhage) in cases of stenting, and no ischemic events during or after the procedures. Restenosis (more than 50% stenosis) occurred in four of 18 cases(22.2%) during mean follow-up period of 12 months. Two patients with VA occlusion before treatment, developed restenosis and reocclusion. Complete total occlusion seems to be a high-risk lesion and strict follow-up is required. In this study, PTA/stenting for intracranial vertebrobasilar artery stenosis or occlusion is an effective treatment, but strict indications may be required because procedure-related 30 days morbidity rate was 5.5% in addition to unclear natural history. PMID:20587244

  6. Aortic Stent-Graft Infection Following Septic Complications of a Kidney Stone

    SciTech Connect

    Berg, H. Rogier van den Leijdekkers, Vanessa J.; Vahl, Anco

    2006-06-15

    A 73-year-old man was treated because of a renal pelvis blowout of the left kidney for which he received a nephrostomy catheter without antibiotic prophylaxis. Almost a year previously this patient had undergone endovascular repair of a symptomatic infrarenal abdominal aorta aneurysm. Four weeks after the diagnosis and treatment of the ruptured renal pelvis, a new computed tomography scan and ultrasound-guided fine needle aspiration confirmed the diagnosis of infected aortic stent-graft. An extra-anatomic axillo-uniiliac bypass and graft excision was performed. Two weeks after discharge the patient returned to the hospital with an occlusion of his left renal artery and died of renal failure. This is the first time an infected aortic stent-graft after a renal pelvis blowout has been reported. Although infections of aortic stent-grafts occur rarely, one should be aware of the possibility in aortic stent-graft patients undergoing abdominal procedures without antibiotic prophylaxis.

  7. [Stent dilatation of pulmonary artery stenosis in the adult patient with congenital heart disease].

    PubMed

    Benito, F; Oliver, J M

    2000-04-01

    Stents have been previously used to resolve stenoses of branch pulmonary arteries in children. We report 3 patients, with mean age of 22.7 +/- 4.7 years and pulmonary artery stenosis after palliative surgery in whom we implanted seven stents in four procedures. Six P308 Palmaz, overlapped two by two, were implanted by venous femoral approach in two patients, receiving four in the first case and the other two in the third case. In the second case, a NIR type stent was implanted through femoral artery in the right pulmonary artery. Stenosis diameter enlarged from 5.3 +/- 2.3 to 14.4 +/- 4.2 mm and the pressure gradient through stenosis fell from 40.6 +/- 15.3 to 6. 5 +/- 5 mmHg. All stents are well deployed and there are two patients waiting for total correction (previously not feasible) during a follow-up of 30.6 +/- 6.1 months.

  8. Alpha horizontal stent delivery for coil embolization of a broad-necked large basilar apex aneurysm: a case report

    PubMed Central

    Ohshima, Tomotaka; Nagakura, Masamune; Nishizawa, Toshihisa; Kato, Kyozo

    2015-01-01

    ABSTRACT Here we describe a novel technique for single stent horizontal reconstruction and coil embolization for a broad-necked large basilar artery (BA) apex aneurysm. A previously healthy 77-year-old woman presented with a broad-necked large BA apex aneurysm. Due to difficulty accessing the right posterior cerebral artery (PCA), we abandoned the Y-stent technique. Instead, we decided to navigate the stent through the BA to the left PCA making a loop of the stent delivery catheter inside the aneurysm in an "alpha" fashion. The procedure outcome was excellent without any complications. Alpha horizontal stent delivery via an antegrade approach for coil embolization of broad-necked large BA apex aneurysms may provide an effective therapeutic alternative, if other techniques are not feasible. PMID:26663945

  9. Three-dimensional reconstruction of coronary stents in vivo based on motion compensated X-ray angiography

    NASA Astrophysics Data System (ADS)

    Schäfer, Dirk; Movassaghi, Babak; Grass, Michael; Schoonenberg, Gert; Florent, Raoul; Wink, Onno; Klein, Andrew J. P.; Chen, James Y.; Garcia, Joel; Messenger, John C.; Carroll, John D.

    2007-03-01

    The complete expansion of the stent during a percutaneous transluminal coronary angioplasty (PTCA) procedure is essential for treatment of a stenotic segment of a coronary artery. Inadequate expansion of the stent is a major predisposing factor to in-stent restenosis and acute thrombosis. Stents are positioned and deployed by fluoroscopic guidance. Although the current generation of stents are made of materials with some degree of radio-opacity to detect their location after deployment, proper stent expansion is hard to asses. In this work, we introduce a new method for the three-dimensional (3D) reconstruction of the coronary stents in-vivo utilizing two-dimensional projection images acquired during rotational angiography (RA). The acquisition protocol consist of a propeller rotation of the X-ray C-arm system of 180°, which ensures sufficient angular coverage for volume reconstruction. The angiographic projections were acquired at 30 frames per second resulting in 180 projections during a 7 second rotational run. The motion of the stent is estimated from the automatically tracked 2D coordinates of the markers on the balloon catheter. This information is used within a motion-compensated reconstruction algorithm. Therefore, projections from different cardiac phases and motion states can be used, resulting in improved signal-to-noise ratio of the stent. Results of 3D reconstructed coronary stents in vivo, with high spatial resolution are presented. The proposed method allows for a comprehensive and unique quantitative 3D assessment of stent expansion that rivals current X-ray and intravascular ultrasound techniques.

  10. Undersized angioplasty and stenting of symptomatic intracranial tight stenosis with Enterprise: Evaluation of clinical and vascular outcome

    PubMed Central

    Lee, Kun-Yu; Chen, David Yen-Ting; Hsu, Hui-Ling; Chen, Chi-Jen

    2015-01-01

    Background Severe intracranial arterial stenosis results in more than 10% incidence of stroke and transient ischemic attack. Using undersized angioplasty with off-label closed-cell Enterprise stent may be a feasible alternative option for treating patients with intracranial atherosclerotic disease who fail dual-antiplatelet medical therapy. The results of the authors’ study are presented in this paper. Materials and methods Between January 2013 and July 2014, 24 symptomatic patients with a total of 30 intracranial arterial stenotic lesions refractory to medical therapy, who underwent undersized angioplasty and Enterprise stenting, were retrospectively reviewed in the authors’ institution. The results evaluated include technical success rate, clinical outcome measured as modified Rankin Scale at presentation and follow-up, peri-procedural morbidity within 30 days and 1 year, and follow-up vessel patency. Results Stent deployment was successfully achieved in all stenotic lesions (30/30). Mean pre-stent and post-stent diameter residual stenosis was 81% and 18%, respectively. The peri-procedural complication rate during 30 days after stenting was 10% per lesion (3/30), including intracranial hemorrhage, in-stent thrombosis and ischemic stroke. No further thromboembolic event or complication occurred in any patient more than 30 days after stenting. Modified Rankin scale ≤ 2 was observed in 64% and 83% of patients at initial presentation and follow-up (mean 15.8 months), respectively. Imaging follow-up was available in 17 of 24 patients (70.8%) and 20 of 30 treated lesions (66.6%) with a mean follow-up period of 15.4 months. Only one asymptomatic in-stent restenosis occurred in 20 available lesions (5.0%). Conclusion This preliminary study suggests that using undersized angioplasty and Enterprise stenting may effectively treat high-degree symptomatic intracranial arterial stenosis with favorable clinical and angiographic outcome. PMID:26542728

  11. Long Term Outcome in Patients with Esophageal Stenting for Cancer Esophagus - Our Experience at a Rural Hospital of Punjab, India

    PubMed Central

    Singh, Abhitesh; Singh, Anantbir; Sharma, Ghansham; Bhatia, Parmod Kumar; Grover, Amarjeet Singh

    2016-01-01

    Introduction Cancer of the esophagus is among the leading cause of cancer deaths in Punjab, India. Patients generally present with dysphagia as their first symptom and more often they have advanced disease at the time of presentation to a tertiary care centre. Palliative procedures have important roles in this setting. Stenting is the best option to palliate the symptoms of dysphagia, from which patient is suffering the most. Aim To know the success rate, early and long term complications and mortality in esophageal stenting, when it was done in malignant esophageal stricture patients. Materials and Methods One hundred patients, who had undergone esophageal stenting from January 2012 to January 2015, were included in the study. We retrospectively analysed the data for patient characteristics, causes of non-operability, early and long term complications, re-interventions, efficacy and mortality. Results Out of 100 patients, indications for stenting were locally advanced disease not amenable to surgery (52%), metastatic disease (35%), CVA (1%), cardiac and respiratory problem (8%), un-willing for surgery in 5% of patients. Majority of patients (94%) had squamous cell carcinoma, while only 6% had adenocarcinoma. 84% of patients presented with dysphagia with or without chest pain and recurrent cough while 16% had recurrent vomiting. 58% had dysphagia to liquids and solids and 17% had complete dysphagia. After stenting 93% had significant improvement in dysphagia score from median of 3 to 1. Post procedure stay was 3.61±1.0 days. One patient had procedure related major complication in the form of post procedural bleed (after 16 days of stenting) leading to death of that patient. Minor complications were present in 52 patients treated conservatively not affecting the efficacy of procedure. These include pain after stenting (38%), stent obstruction (23%) and stent migration (6%). All the minor complications were treated conservatively except in six patients in whom re-stenting

  12. Prevention of Intracranial In-stent Restenoses: Predilatation with a Drug Eluting Balloon, Followed by the Deployment of a Self-Expanding Stent

    SciTech Connect

    Vajda, Zsolt Guethe, Thomas Perez, Marta Aguilar Kurre, Wiebke; Schmid, Elisabeth Baezner, Hansjoerg; Henkes, Hans

    2013-04-15

    Stenting in intracranial atherosclerotic disease (ICAD) is increasingly debated, due to issues of procedural safety, technical efficacy, and in-stent recurrent stenoses (ISR). In the present study, feasibility, safety, and efficacy of angioplasty using a drug-eluting balloon (DEB) followed by the implantation of a self-expanding stent (Enterprise) were evaluated for the treatment of ICAD lesions. Fifty-two patients (median age: 71 years; range: 54-86 years; male/female ratio 37:15) underwent stenting of high-grade ICAD lesions between February 2010 and November 2011 in a single center. Angioplasty using a paclitaxel coated SeQuent Please (B. Braun, Germany) or DIOR (Eurocor, Germany) coronary PTCA balloon, followed by the implantation of a self-expanding stent (Enterprise, Codman, USA) was performed in 54 lesions. Angiographic and clinical follow-up was performed at 6 and 12 weeks, 6 and 12 months, and yearly thereafter. Technical success rate, periprocedural complications, occurrence of recurrent ischemic symptoms, and the development of an ISR were analyzed. Angioplasty using a DEB followed by stent implantation was successfully performed in 44 (81 %) cases. DEB insertion failed in 19 % of the cases and angioplasty was finally performed using a conventional PTCA balloon. The combined procedure related permanent neurologic morbidity and mortality rate (stroke, ICH, and subarachnoid hemorrhage) at 30 days and beyond was 5 %. Angiographic and clinical follow-up were obtained in 33 (61 %) lesions in 32 patients. Recurrent stenosis was seen in one (3 %) lesion. Angioplasty and stenting using a DEB is safe and yields encouragingly low ISR rates. Further technical developments to improve lesion accessibility are, nevertheless, mandatory.

  13. Quantitative analysis of 3D stent reconstruction from a limited number of views in cardiac rotational angiography

    NASA Astrophysics Data System (ADS)

    Perrenot, Béatrice; Vaillant, Régis; Prost, Rémy; Finet, Gérard; Douek, Philippe; Peyrin, Françoise

    2007-03-01

    Percutaneous coronary angioplasty consists in conducting a guidewire carrying a balloon and a stent through the lesion and deploying the stent by balloon inflation. A stent is a small 3D complex mesh hardly visible in X-ray images : the control of stent deployment is difficult although it is important to avoid post intervention complications. In a previous work, we proposed a method to reconstruct 3D stent images from a set of 2D cone-beam projections acquired in rotational acquisition mode. The process involves a motion compensation procedure based on the position of two markers located on the guidewire in the 2D radiographic sequence. Under the hypothesis that the stent and markers motions are identical, the method was shown to generate a negligible error. If this hypothesis is not fulfilled, a solution could be to use only the images where motion is weakest, at the detriment of having a limiter number of views. In this paper, we propose a simulation based study of the impact of a limited number of views in our context. The chain image involved in the acquisition of X-ray sequences is first modeled to simulate realistic noisy projections of stent animated by a motion close to cardiac motion. Then, the 3D stent images are reconstructed using the proposed motion compensation method from gated projections. Two gating strategies are examined to select projection in the sequences. A quantitative analysis is carried out to assess reconstruction quality as a function of noise and acquisition strategy.

  14. Drug eluting biliary stents to decrease stent failure rates: A review of the literature

    PubMed Central

    Shatzel, Joseph; Kim, Jisoo; Sampath, Kartik; Syed, Sharjeel; Saad, Jennifer; Hussain, Zilla H; Mody, Kabir; Pipas, J Marc; Gordon, Stuart; Gardner, Timothy; Rothstein, Richard I

    2016-01-01

    Biliary stenting is clinically effective in relieving both malignant and non-malignant obstructions. However, there are high failure rates associated with tumor ingrowth and epithelial overgrowth as well as internally from biofilm development and subsequent clogging. Within the last decade, the use of prophylactic drug eluting stents as a means to reduce stent failure has been investigated. In this review we provide an overview of the current research on drug eluting biliary stents. While there is limited human trial data regarding the clinical benefit of drug eluting biliary stents in preventing stent obstruction, recent research suggests promise regarding their safety and potential efficacy. PMID:26839648

  15. Cost-Effectiveness Analysis of Infrapopliteal Drug-Eluting Stents

    SciTech Connect

    Katsanos, Konstantinos Karnabatidis, Dimitris; Diamantopoulos, Athanasios; Spiliopoulos, Stavros; Siablis, Dimitris

    2013-02-15

    IntroductionThere are no cost-utility data about below-the-knee placement of drug-eluting stents. The authors determined the cost-effectiveness of infrapopliteal drug-eluting stents for critical limb ischemia (CLI) treatment. The event-free individual survival outcomes defined by the absence of any major events, including death, major amputation, and target limb repeat procedures, were reconstructed on the basis of two published infrapopliteal series. The first included spot Bail-out use of Sirolimus-eluting stents versus bare metal stents after suboptimal balloon angioplasty (Bail-out SES).The second was full-lesion Primary Everolimus-eluting stenting versus plain balloon angioplasty and bail-out bare metal stenting as necessary (primary EES). The number-needed-to-treat (NNT) to avoid one major event and incremental cost-effectiveness ratios (ICERs) were calculated for a 3-year postprocedural period for both strategies. Overall event-free survival was significantly improved in both strategies (hazard ratio (HR) [confidence interval (CI)]: 0.68 [0.41-1.12] in Bail-out SES and HR [CI]: 0.53 [0.29-0.99] in Primary EES). Event-free survival gain per patient was 0.89 (range, 0.11-3.0) years in Bail-out SES with an NNT of 4.6 (CI: 2.5-25.6) and a corresponding ICER of 6,518 Euro-Sign (range 1,685-10,112 Euro-Sign ). Survival gain was 0.91 (range 0.25-3.0) years in Primary EES with an NNT of 2.7 (CI: 1.7-5.8) and an ICER of 11,581 Euro-Sign (range, 4,945-21,428 Euro-Sign ) per event-free life-year gained. Two-way sensitivity analysis showed that stented lesion length >10 cm and/or DES list price >1000 Euro-Sign were associated with the least economically favorable scenario in both strategies. Both strategies of bail-out SES and primary EES placement in the infrapopliteal arteries for CLI treatment exhibit single-digit NNT and relatively low corresponding ICERs.

  16. Subintimal Recanalization of Occluded Stents: The Substent Technique

    SciTech Connect

    Diamantopoulos, Athanasios Katsanos, Konstantinos; Spiliopoulos, Stavros; Karnabatidis, Dimitris; Siablis, Dimitris

    2013-08-01

    PurposeApplication of metal stents is complicated by neointimal hyperplasia leading to vessel restenosis and reocclusion. Treatment options in cases presenting with complete occlusion of the stented segment and recurrent critical limb ischemia (CLI) are limited. We present the option of the subintimal/substent technique in dealing with occluded stents.MethodsThe study included patients presenting with recurrent CLI due to impaired blood flow as a result of complete occlusion of previously inserted metal stents and unsuccessful intraluminal crossing of the lesion via either the antegrade or retrograde approach. In these cases, crossing the occlusion through the subintimal/substent plane was attempted. Primary end points included technical success, safety of the procedure, clinical improvement, and limb salvage, while secondary end points were patient survival, primary patency, and vessel restenosis rates at 1-year follow-up. Study end points were calculated by Kaplan-Meier survival analysis.ResultsBetween July 2006 and October 2011, a total of 14 patients (mean age 69.14 {+-} 12.59 years, 12 men) were treated with the substent technique and included in the analysis. Technical success rate was 85.71 % (12 of 14), with a total lesion length of 193.57 {+-} 90.78 mm. The mean occluded stented segment length was 90.21 {+-} 44.34 mm. In 10 (83.33 %) of 12 cases, a new stent had to be placed by the side of the old occluded one, while the remaining two cases (16.67 %) were treated only with balloon angioplasty. No serious adverse events were noted during the immediate postprocedural period. All successfully treated patients improved clinically. Estimated limb salvage was 90.9 %, and patient survival rate was 90.0 % at 1 year's follow-up. Primary patency was 45.50 % and vessel restenosis 77.30 %.ConclusionSubintimal recanalization of occluded metal stents through the substent plane is a valuable alternative treatment option, especially in patients with recurrent CLI with few

  17. Stent-grafts placement for treatment of massive hemorrhage from ruptured hepatic artery after pancreaticoduodenectomy

    PubMed Central

    Wang, Mao-Qiang; Liu, Feng-Yong; Duan, Feng; Wang, Zhi-Jun; Song, Peng; Fan, Qing-Sheng

    2010-01-01

    AIM: To present a series of cases with life-threatening hemorrhage from ruptured hepatic artery pseudoaneurysm after pancreaticoduodenectomy (PD) treated with placement of stent-grafts. METHODS: Massive hemorrhage from ruptured hepatic artery pseudoaneurysm after PD in 9 patients (6 men, 3 women) at the age of 23-75 years (mean 48 years), were treated with placement of percutaneous endovascular balloon-expandable coronary stent-grafts. All patients were not suitable for embolization because of a non-patent portal vein. One or more stent-grafts, ranging 3-6 mm in diameter and 16-55 mm in length, were placed to exclude ruptured pseudoaneurysm. Follow-up data, including clinical condition, liver function tests, and Doppler ultrasound examination, were recorded at the outpatient clinic. RESULTS: Immediate technical success was achieved in all the 9 patients. All stent-grafts were deployed in the intended position for immediate cessation of bleeding and preservation of satisfactory hepatic arterial blood flow. No significant procedure-related complications occurred. Recurrent bleeding occurred in 2 patients at 16 and 24 h, respectively, after placement of stent-grafts and treated with surgical revision. One patient died of sepsis 12 d after the interventional procedure. The remaining 6 patients were survived when they were discharged. The mean follow-up time was 10.5 mo (range 4-16 mo). No patient had recurrent bleeding after discharge. Doppler ultrasound examination verified the patency of hepatic artery and stent-grafts during the follow-up. CONCLUSION: Placement of stent-grafts is an effective and safe procedure for acute life-threatening hemorrhage from ruptured hepatic artery pseudoaneurysm. PMID:20677346

  18. Comparison of a New Polytetrafluoroethylene-Covered Metallic Stent to a Noncovered Stent in Canine Ureters

    SciTech Connect

    Chung, Hwan-Hoon Lee, Seung Hwa; Cho, Sung Bum; Park, Hong Suk; Kim, Young Sik; Kang, Byung Chul; Frisoli, Joan K.; Razavi, Mahmood K.

    2008-05-15

    The aim of this study was to determine the feasibility of using a newly designed polytetrafluoroethylene (PTFE)-covered metallic stent in the ureter by comparing its effectiveness with that of the noncovered stent in a canine model. We placed 14 stents in the ureters of seven mongrel dogs that weighed 30-40 kg each. The covered and noncovered stents were deployed in the right and left ureters, respectively, of six dogs. In the seventh dog, a covered stent and a double-J catheter were inserted in the right ureter, and a covered stent only was inserted in the left ureter. The first six dogs were sacrificed at 5, 10, and 15 weeks after deployment of the stents (two for each follow-up period), and the seventh dog was sacrificed at 30 weeks. There was no migration or poor expansion of any of the stents observed on plain radiography. On intravenous pyelogram and retrograde pyelogram, all of the covered stents at each follow-up period had patent lumens at the stented segments without hydronephrosis, and the passage of contrast material through it was well preserved. The noncovered stents in the dogs sacrificed at 5 and 10 weeks and one of the two dogs sacrificed at 15 weeks showed near-complete occlusion of the stent lumen due to ingrowth of the soft tissue, and severe hydronephrosis was also noted. The noncovered stent in the other dog sacrificed at 15 weeks showed the passage of contrast material without hydronephrosis, but the lumen of the stent was still nearly occluded by the soft tissue. There was no evidence of hydronephrosis or passage disturbance of the contrast material in both ureters of the dog sacrificed at 30 weeks. We conclude that the newly designed PTFE-covered stent effectively prevented the luminal occlusion caused by urothelial hyperplasia compared to the near-total occlusion of the noncovered stents, and no migration of the covered stents was noted.

  19. Emergency Renal Ablation for Life-Threatening Hemorrhage from Multiple Capsular Branches During Renal Artery Stenting

    SciTech Connect

    Aytekin, Cuneyt Yildirim, Utku M.; Ozyer, Umut; Harman, Ali; Boyvat, Fatih

    2010-06-15

    A 55-year-old woman underwent bilateral renal artery stent placement with good angiographic result. After the procedure, the patient complained of left flank pain secondary to subcapsular hematoma. Retrospective evaluation of images taken during stent implantation favored the diagnosis of guidewire perforation. Three hours after the procedure, contrast-enhanced computed tomography and subsequent renal angiography showed multifocal extravasations. We performed emergent renal ablation for the treatment of massive bleeding. To our knowledge, this is the first use of transcatheter renal ablation technique for this purpose.

  20. Stent-Assisted Clip Placement for Complex Internal Carotid Artery Intracranial Aneurysms

    PubMed Central

    Qureshi, Adnan I.; Chughtai, Morad; Khan, Asif A.; Suri, M. Fareed K.; Sherr, Gregory T.

    2016-01-01

    BACKGROUND We report two procedures using a stent-assisted microsurgical clip placement to treat complex intracranial aneurysms originating from supraclinoid segment of the internal carotid artery. CASE DESCRIPTIONS In both procedures, primary clip placement was considered technically difficult due to either complex morphology or inferior protrusion of aneurysm fundus within the interclinoid space. A nitinol self-expanding stent was placed across the neck of the aneurysm either preoperatively or intraoperatively. Obliteration of aneurysm and patency of the artery was confirmed by angiography after clip placement. CONCLUSION Description of an integrated open microsurgical and endovascular approach and review of literature pertaining to considerations for treatment approach are discussed. PMID:26958150

  1. Impact of bifurcation dual stenting on endothelial shear stress

    PubMed Central

    Chen, Henry Y.; Koo, Bon-Kwon

    2015-01-01

    Despite advances in percutaneous coronary interventions and the introduction of drug eluding stents, in-stent restenosis and stent thrombosis remain a clinically significant problem for bifurcations. The aim of this study is to determine the effect of dual bifurcation stenting on hemodynamic parameters known to influence restenosis and thrombosis. We hypothesized that double stenting, especially with a longer side branch (SB) stent, likely has a negative effect on wall shear stress (WSS), WSS gradient (WSSG), and oscillatory shear index (OSI). To test this hypothesis, we developed computational models of dual stents at bifurcations and non-Newtonian blood simulations. The models were then interfaced, meshed, and solved in a validated finite-element package. Longer and shorter stents at the SB and provisional stenting were compared. It was found that stents placed in the SB at a bifurcation lowered WSS, but elevated WSSG and OSI. Dual stenting with longer SB stent had the most adverse impact on SB endothelial WSS, WSSG, and OSI, with low WSS region up to 50% more than the case with shorter SB stent. The simulations also demonstrated flow disturbances resulting from SB stent struts protruding into the main flow field near the carina, which may have implications on stent thrombosis. The simulations predict a negative hemodynamic role for SB stenting, which is exaggerated with a longer stent, consistent with clinical trial findings that dual-stenting is comparable or inferior to provisional stenting. PMID:26183473

  2. Stent-Grafts for Unruptured Abdominal Aortic Aneurysms: Current Status

    SciTech Connect

    Rose, John

    2006-06-15

    Aortic stent-grafts were introduced at the beginning of the 1990s as a less invasive method of dealing with aortic aneurysms in patients with poor cardiovascular reserve. The numbers of procedures performed worldwide has increased exponentially despite the current lack of any substantial evidence for long-term efficacy in comparison with the gold standard of open surgical grafting. This review summarizes the evolution of the abdominal aortic stent-graft, the techniques used for assessment and deployment, and the effect of the procedure on both the patient and the device. The recent publication of two national multicenter trials has confirmed that the endovascular technique confers a 2.5-fold reduction in 30-day mortality in comparison with open surgery. However, over 4 years of follow-up, there is a 3-fold increase in the risk of reintervention and the overall costs are 30% greater with endovascular repair. Although the improvement in aneurysm-related mortality persists in the mid-term, because of the initial reduction in perioperative mortality, the all-cause mortality rate at 4 years is actually no better than for open surgery. Longer-term data from the randomized trials are awaited as well as results from the latest trials utilizing state-of-the-art devices. Whilst the overall management of abdominal aortic aneurysms has undoubtedly benefited from the introduction of stent-grafts, open repair currently remains the gold standard treatment.

  3. Covered stent in the superior gluteal artery in a hybrid approach to treat internal iliac artery aneurysm: a technical note.

    PubMed

    Noël-Lamy, Maxime; Teng Tan, Kong; Lindsay, Thomas

    2015-07-01

    This brief report describes a hybrid endovascular and open procedure to treat internal iliac artery (IIA) aneurysms and preserve pelvic blood flow. A covered stent was deployed before surgery in the superior gluteal artery, extending across the IIA aneurysm, with the proximal end in the common iliac artery lumen. During open aortoiliac aneurysm repair, the stent graft was anastomosed in an end-to-side manner to the surgical graft. Four aneurysms were treated in 3 patients. Technical success was achieved in all cases. There were no complications or repeat interventions. Stents were all patent at imaging follow-up (range, 6-25 mo). Patients were free from buttock claudication.

  4. Endoscopic stenting for laparoscopic sleeve gastrectomy leaks

    PubMed Central

    Aydın, Mehmet Timuçin; Alahdab, Yeşim Özen; Aras, Orhan; Karip, Bora; Onur, Ender; İşcan, Yalın; Memişoğlu, Kemal

    2016-01-01

    Objective Laparoscopic sleeve gastrectomy is a widely accepted and effective bariatric surgery method. The rate of leakage at the staple-line has been reported to be between 1.5 and 5%. Aside from the use of percutaneous drainage, re-laparoscopy, or abdominal sepsis control by laparotomy, endoscopic esophagogastric stent placement is increasingly preferred as a treatment method. Because laparoscopic sleeve gastrectomy is a widely used modality in our hospital, we aimed to evaluate the rate of leaks and the results of stent placements in our patients. Material and Methods Between January 1st 2010 and August 31st 2014, laparoscopic sleeve gastrectomy was performed on 236 patients by three surgeons. The demographic information and postoperative discharge summaries were collected and analyzed with the permission of the hospital ethics committee. Information about leak treatment management was also collected. Results Leaks after laparoscopic sleeve gastrectomy in four patients were stented in the first postoperative month. Short (12 cm) Hanora® (M.I.Tech, Gyeonggi-do, Korea) self-expandable coated stents were placed in two patients, and long (24 cm) Hanora® self-expandable coated stents were placed in the other two. The stents were removed after one month in two patients, two and a half months later in one, and five months later in another patient. The leaks were demonstrated to be healed in all patients after stent removal. Endoscopic stent revision was performed in one patient due to migration of the stent and in another for stent breakage. Conclusion The success rate of treatment of leaks after laparoscopic sleeve gastrectomy by stent placement has been variable in the literature. The success in early stent placement has been shown to be related to physician expertise. According to the results of our patients, we suggest that endoscopic stent placement in the early stage after controlling sepsis is an effective method in the management of leaks. PMID:28149125

  5. [Drug-eluting stents do they make the difference? ].

    PubMed

    Presbitero, P; Asioli, M

    2002-10-01

    The main limitation to further expansion of PTCI (percutaneous transluminal coronary intervention) is restenosis that occurs in 30% of the patients within 6-months after the procedure. Coronary stenting decreases the percent of restenosis due to arterial remodeling after PTCI but proliferation of smooth muscle cells due to vascular injury still remains. A mechanical approach the only treatment up to now (further balloon expansion, plaque removal with rotablator or directional atherectomy) failed. Because the restenotic process is due to a complex series of biological events which start with platelet aggregation, grow-factors and cytochine release, the use of antiflammatory, antithrombotic and antiproliferative drugs were attempted. Cortisone and heparin showed low benefits in clinical trial. New drugs (rapamycin, taxol, actinomycin D, tacrolimus, estradiol, dexamethazone) with antiproliferative and antiflammatory activities are under evaluation. They act as inhibitors of the cell migration and of the cell cicle progression with different specific molecular mechanisms. The first pilot study performed in 45 patients with sirolimus-eluting stents has shown a sustained suppression (25% in the fast release group and 23% in the slow release group) of neointimal formation at 12 months after procedure with absence of restenosis. The Ravel study, a randomized trial, has enrolled 238 patients treated with sirolimus coated stent vs a control group: the results confirm the previous data with a complete suppression of intimal hyperproliferation and restenosis at six months follow-up. The first 400 patients treated in the Sirius trial a similar study which will randomize 1100 pts show a low, but not a complete inhibition of the restenotic process probably due to a more complexity of the lesions treated in comparison to Ravel trial (9.2% of restenosis). Another very promising drug is taxol (paclitaxel). It is an antiproliferative and antinflammatory molecule tested in a series of

  6. Endovascular Exclusion of Abdominal Aortic Aneurysms: Initial Experience with Stent-Grafts in Cardiology Practice

    PubMed Central

    Howell, Marcus H.; Zaqqa, Munir; Villareal, Rollo P.; Strickman, Neil E.; Krajcer, Zvonimir

    2000-01-01

    The use of an endovascular stent-graft prosthesis for the treatment of infrarenal abdominal aortic aneurysms is receiving increasing attention as an option that may avoid the significant morbidity and mortality associated with open surgical treatment. We studied the clinical effectiveness of stent-grafts in patients with infrarenal abdominal aortic aneurysms. Between October 1995 and May 1998, 33 patients underwent infrarenal abdominal aortic aneurysm exclusion with a homemade polytetrafluoroethylene-covered stent, and between November 1998 and September 1999, 56 patients underwent abdominal aortic aneurysm exclusion with the Medtronic AneuRx stent-graft. Overall, these patients represented a high-risk surgical group. The technical success rate was 100% in both groups. No patient required immediate conversion to open repair. With the polytetrafluoroethy-lene-covered stent, the primary success rate was 33%, and the secondary success rate was 76%. In the AneuRx group, the primary success rate was 82.8%, and the secondary success rate was 85.3% at 6 months. There was no procedural or 1-month mortality or major morbidity in either group. By showing that infrarenal abdominal aortic aneurysms can be treated safely and successfully with an endoluminal stent-graft, our early results provide additional support for the endovascular treatment of abdominal aortic aneurysms. Further follow-up studies will determine the long-term ability of such treatment to prevent aneurysmal rupture and death. PMID:10928501

  7. A Newly Designed Stent for Management of Malignant Distal Duodenal Stenosis

    SciTech Connect

    Zhou, Wei-Zhong Yang, Zheng-Qiang Liu, Sheng Zhou, Chun-Gao Xia, Jin-Guo Zhao, Lin-Bo Shi, Hai-Bin

    2015-02-15

    PurposeTo evaluate the clinical effectiveness of a newly designed stent for the treatment of malignant distal duodenal stenosis.MethodsFrom March 2011 to May 2013, six patients with malignant duodenal stenosis underwent fluoroscopically guided placement of the new duodenal stent consisting of braided, nested stent wires, and a delivery system with a metallic mesh inner layer. Primary diseases were pancreatic cancer in three patients, gastric cancer in two patients, and endometrial stromal sarcoma in one patient. Duodenal obstructions were located in the horizontal part in two patients, the ascending part in two patients, and the duodenojejunal flexure in two patients. Technical success, defined as the successful stent deployment, clinical symptoms before and after the procedure, and complications were evaluated.ResultsTechnical success was achieved in all patients. No major complications were observed. Before treatment, two patients could not take any food and the gastric outlet obstruction scoring system (GOOSS) score was 0; the other four patients could take only liquids orally (GOOSS score = 1). After treatment, five patients could take soft food (GOOSS score = 2) and one patient could take a full diet (GOOSS score = 3). The mean duration of primary stent patency was 115.7 days.ConclusionsThe newly designed stent is associated with a high degree of technical success and good clinical outcome and may be clinically effective in the management of malignant distal duodenal obstruction.

  8. Clinical effect of double coaxial self-expandable metallic stent in management of malignant colon obstruction

    PubMed Central

    Won, Yoodong; Lee, Su Lim; Ku, Young Mi; Kim, Ki Tae; Won, Hye Sung; An, Chang Hyeok

    2015-01-01

    PURPOSE We aimed to evaluate the clinical effectiveness and safety of double coaxial self-expandable metallic stent (DCSEMS) in management of malignant colonic obstruction as a bridge to surgery or palliation for inoperable patients. METHODS Between April 2006 and December 2012, 49 patients (27 males and 22 females; median age, 68 years; age range, 38–91 years) were selected to receive decompressive therapy for malignant colonic obstruction by implanting a DCSEMS. Application of DCSEMS was attempted in 49 patients under fluoroscopic guidance. The obstruction was located in the transverse colon (n=2), descending colon (n=7), sigmoid colon (n=24), rectosigmoid junction (n=6), and the rectum (n=10). The intended use of DCSEMS was as a bridge to elective surgery in 23 patients and palliation in 26 patients. RESULTS Clinical success, defined as >50% dilatation of the stent with subsequent symptomatic improvement, was achieved in 48 of 49 patients (98%). The stent was properly inserted in all patients. No immediate major procedure-related complications occurred. One patient in the bridge-to-surgery group had colon perforation three days after DCSEMS application. Four patients had late migrations of the double stent. CONCLUSION Application of DCSEMS is safe and effective in management of malignant colonic obstruction; it prevents stent migration and tumor ingrowth and lowers perforation rate during the stent application. PMID:25698096

  9. Drug-Eluting Stents: Do They Increase Heart Attack Risk?

    MedlinePlus

    ... intervention, or PCI). Drug-eluting stents have a polymer coating over mesh that emits a drug over ... 2014. Bangalore S, et al. Bare metal stents, durable polymer drug eluting stents, and biodegradable polymer drug eluting ...

  10. Cerebral foreign body reaction after carotid aneurysm stenting

    PubMed Central

    Lorentzen, Anastasia Orlova; Nome, Terje; Bakke, Søren Jacob; Scheie, David; Stenset, Vidar

    2016-01-01

    Flow diverter stents are new important tools in the treatment of large, giant, or wide-necked aneurysms. Their delivery and positioning may be difficult due to vessel tortuosity. Common adverse events include intracranial hemorrhage and ischemic stroke, which usually occurs within the same day, or the next few days after the procedure. We present a case where we encountered an unusual intracerebral complication several months after endovascular treatment of a large left internal carotid artery aneurysm, and where brain biopsy revealed foreign body reaction to hydrophilic polymer fragments distally to the stent site. Although previously described, embolization of polymer material from intravascular equipment is rare. We could not identify any other biopsy verified case in the literature, with this particular presentation of intracerebral polymer embolization – a multifocal inflammation spread out through the white matter of one hemisphere without hemorrhage or ischemic changes. PMID:26510943

  11. A Budget Impact Model for Paclitaxel-eluting Stent in Femoropopliteal Disease in France

    SciTech Connect

    De Cock, Erwin; Sapoval, Marc; Julia, Pierre; Lissovoy, Greg de; Lopes, Sandra

    2013-04-15

    The Zilver PTX drug-eluting stent (Cook Ireland Ltd., Limerick, Ireland) represents an advance in endovascular treatments for atherosclerotic superficial femoral artery (SFA) disease. Clinical data demonstrate improved clinical outcomes compared to bare-metal stents (BMS). This analysis assessed the likely impact on the French public health care budget of introducing reimbursement for the Zilver PTX stent. A model was developed in Microsoft Excel to estimate the impact of a progressive transition from BMS to Zilver PTX over a 5-year horizon. The number of patients undergoing SFA stenting was estimated on the basis of hospital episode data. The analysis from the payer perspective used French reimbursement tariffs. Target lesion revascularization (TLR) after primary stent placement was the primary outcome. TLR rates were based on 2-year data from the Zilver PTX single-arm study (6 and 9 %) and BMS rates reported in the literature (average 16 and 22 %) and extrapolated to 5 years. Net budget impact was expressed as the difference in total costs (primary stenting and reinterventions) for a scenario where BMS is progressively replaced by Zilver PTX compared to a scenario of BMS only. The model estimated a net cumulative 5-year budget reduction of Euro-Sign 6,807,202 for a projected population of 82,316 patients (21,361 receiving Zilver PTX). Base case results were confirmed in sensitivity analyses. Adoption of Zilver PTX could lead to important savings for the French public health care payer. Despite higher initial reimbursement for the Zilver PTX stent, fewer expected SFA reinterventions after the primary stenting procedure result in net savings.

  12. An Assessment of Radiologically Inserted Transoral and Transgastric Gastroduodenal Stents to Treat Malignant Gastric Outlet Obstruction

    SciTech Connect

    Miller, Bethany H. T.; Griffiths, Ewen A.; Pursnani, Kishore G. Ward, Jeremy B.; Stockwell, Robert C.

    2013-12-15

    IntroductionSelf-expanding metallic stents (SEMS) are used to palliate malignant gastric outlet obstruction (GOO) and are useful in patients with limited life expectancy or severe medical comorbidity, which would preclude surgery. Stenting can be performed transorally or by a percutaneous transgastric technique. Our goal was to review the outcome of patients who underwent radiological SEMS insertion performed by a single consultant interventional radiologist. Methods: Patients were identified from a prospectively collected database held by one consultant radiologist. Data were retrieved from radiological reports, multidisciplinary team meetings, and the patients' case notes. Univariate survival analysis was performed. Results: Between December 2000 and January 2011, 100 patients (63 males, 37 females) had 110 gastroduodenal stenting procedures. Median age was 73 (range 39-89) years. SEMS were inserted transorally (n = 66) or transgastrically (n = 44). Site of obstruction was the stomach (n = 37), duodenum (n = 50), gastric pull-up (n = 10), or gastroenterostomy (n = 13). Seven patients required biliary stents. Technical success was 86.4 %: 83.3 % for transoral insertion, 90.9 % for transgastric insertion. Eleven patients developed complications. Median GOO severity score: 1 pre-stenting, 2 post-stenting (p = 0.0001). Median survival was 54 (range 1-624) days. Post-stenting GOO severity score was predictive of survival (p = 0.0001). Conclusions: The technical success rate for insertion of palliative SEMS is high. Insertional technique can be tailored to the individual depending on the location of the tumor and whether it is possible to access the stomach percutaneously. Patients who have successful stenting and return to eating a soft/normal diet have a statistically significant increase in survival.

  13. Is the Routine Check Nephrostogram Following Percutaneous Antegrade Ureteric Stent Placement Necessary?

    SciTech Connect

    Soh, Keng Chuan; Tay, Kiang Hiong Tan, Bien Soo; MM Htoo, Austin; HG Lo, Richard; Lin, Shueh En

    2008-05-15

    Our aim was to review our experience with percutaneous antegrade ureteric stent (PAUS) placement and to determine if the routinely conducted check nephrostogram on the day following ureteric stent placement was necessary. Retrospective review of patients who had undergone PAUS placement between January 2004 and December 2005 was performed. There were 83 subjects (36 males, 47 females), with a mean age of 59.9 years (range, 22-94 years). Average follow-up duration was 7.1 months (range, 1-24 months). The most common indications for PAUS placement were ureteric obstruction due to metastatic disease (n = 56) and urinary calculi (n = 34). Technical success was 93.2% (96/103 attempts), with no major immediate procedure-related complications or mortalities. The Bard 7Fr Urosoft DJ Stent was used in more than 95% of the cases. Eighty-one of 89 (91.0%) check nephrostograms demonstrated a patent ureteric stent with resultant safety catheter removal. Three check nephrostograms revealed distal stent migration requiring repositioning by a goose-snare, while five others showed stent occlusion necessitating permanent external drainage by nephrostomy drainage catheter reinsertion. Following PAUS placement, the serum creatinine level improved or stabilized in 82% of patients. The serum creatinine outcome difference between the groups with benign and malignant indications for PAUS placement was not statistically significant (p = 0.145) but resolution of hydronephrosis was significantly better (p = 0.008) in patients with benign indications. Percutaneous antegrade ureteric stent placement is a safe and effective means of relief for ureteric obstruction. The check nephrostogram following ureteric stent placement was unnecessary in the majority of patients.

  14. On the necessity of modelling fluid-structure interaction for stented coronary arteries.

    PubMed

    Chiastra, Claudio; Migliavacca, Francesco; Martínez, Miguel Ángel; Malvè, Mauro

    2014-06-01

    Although stenting is the most commonly performed procedure for the treatment of coronary atherosclerotic lesions, in-stent restenosis (ISR) remains one of the most serious clinical complications. An important stimulus to ISR is the altered hemodynamics with abnormal shear stresses on endothelial cells generated by the stent presence. Computational fluid dynamics is a valid tool for studying the local hemodynamics of stented vessels, allowing the calculation of the wall shear stress (WSS), which is otherwise not directly possible to be measured in vivo. However, in these numerical simulations the arterial wall and the stent are considered rigid and fixed, an assumption that may influence the WSS and flow patterns. Therefore, the aim of this work is to perform fluid-structure interaction (FSI) analyses of a stented coronary artery in order to understand the effects of the wall compliance on the hemodynamic quantities. Two different materials are considered for the stent: cobalt-chromium (CoCr) and poly-l-lactide (PLLA). The results of the FSI and the corresponding rigid-wall models are compared, focusing in particular on the analysis of the WSS distribution. Results showed similar trends in terms of instantaneous and time-averaged WSS between compliant and rigid-wall cases. In particular, the difference of percentage area exposed to TAWSS lower than 0.4Pa between the CoCr FSI and the rigid-wall cases was about 1.5% while between the PLLA cases 1.0%. The results indicate that, for idealized models of a stented coronary artery, the rigid-wall assumption for fluid dynamic simulations appears adequate when the aim of the study is the analysis of near-wall quantities like WSS.

  15. ePTFE/FEP-Covered Metallic Stents for Palliation of MalignantBiliary Disease: Can Tumor Ingrowth Be Prevented?

    SciTech Connect

    Hatzidakis, Adam Krokidis, Miltiadis; Kalbakis, Kostantinos; Romanos, Jiannis; Petrakis, Ioannis; Gourtsoyiannis, Nicholas

    2007-09-15

    Purpose. To determine the application and clinical effectiveness of ePTFE/FEP-covered metallic stents for palliation of malignant biliary disease, and to evaluate the efficiency of stent coverage in preventing tumor ingrowth. Methods. During a 3-year period, 36 patients with malignant obstructive jaundice were treated with ePTFE/FEP-covered stents, with or without proximal side holes. The stricture was located in the lower common bile duct (CBD) in 18 cases, the upper CBD in 9, the lower common hepatic duct (CHD) in 6, and the upper CHD in 3 patients. Results.Thirty-seven covered stents were percutaneously implanted. The technical success rate was 97%. Reintervention was required in 6 cases. The 30-day mortality rate was 40%, not procedure-related. Mean survival was 128 days. Primary patency rates were 100%,55.5%, and 25% at 3, 6, and 12 months, respectively, while the assisted patency rate was 100% at 12 months. Stents without side holes had higher primary patency rates compared with those with side holes, where occlusion was always due to tumor ingrowth. Tumor ingrowth did not occur in the completely covered stents. No stent dysfunction due to sludge incrustation was found.Complications were 1 case of arterial laceration that occurred during percutaneous transhepatic cholangiography, and a subcapsular hematoma and 1 case of bile peritonitis, that both occurred during primary stenting. No complications followed the secondary stenting technique. Conclusion. ePTFE/FEP-covered metallic stents are safe and effective for palliation of malignant biliary disease. The presence of the ePTFE/FEP coating is likely to prevent from tumor ingrowth.

  16. Stenting for Peripheral Artery Disease of the Lower Extremities

    PubMed Central

    2010-01-01

    a combination of ultrasound and wave form recordings to evaluate arterial flow in blood vessels. The value of the ABI can provide an assessment of the severity of the disease. Other non invasive imaging techniques include: Computed Tomography (CT) and Magnetic Resonance Angiography (MRA). Definitive diagnosis of PAD can be made by an invasive catheter based angiography procedure which shows the roadmap of the arteries, depicting the exact location and length of the stenosis / occlusion. Angiography is the standard method against which all other imaging procedures are compared for accuracy. More than 70% of the patients diagnosed with PAD remain stable or improve with conservative management of pharmacologic agents and life style modifications. Significant PAD symptoms are well known to negatively influence an individual quality of life. For those who do not improve, revascularization methods either invasive or non-invasive can be used to restore peripheral circulation. Technology Under Review A Stent is a wire mesh “scaffold” that is permanently implanted in the artery to keep the artery open and can be combined with angioplasty to treat PAD. There are two types of stents: i) balloon-expandable and ii) self expandable stents and are available in varying length. The former uses an angioplasty balloon to expand and set the stent within the arterial segment. Recently, drug-eluting stents have been developed and these types of stents release small amounts of medication intended to reduce neointimal hyperplasia, which can cause re-stenosis at the stent site. Endovascular stenting avoids the problem of early elastic recoil, residual stenosis and flow limiting dissection after balloon angioplasty. Research Questions In individuals with PAD of the lower extremities (superficial femoral artery, infra-popliteal, crural and iliac artery stenosis or occlusion), is primary stenting more effective than percutaneous transluminal angioplasty (PTA) in improving patency? In

  17. Carotid artery stenting compared with endarterectomy in patients with symptomatic carotid stenosis (International Carotid Stenting Study): an interim analysis of a randomised controlled trial

    PubMed Central

    2010-01-01

    Summary Background Stents are an alternative treatment to carotid endarterectomy for symptomatic carotid stenosis, but previous trials have not established equivalent safety and efficacy. We compared the safety of carotid artery stenting with that of carotid endarterectomy. Methods The International Carotid Stenting Study (ICSS) is a multicentre, international, randomised controlled trial with blinded adjudication of outcomes. Patients with recently symptomatic carotid artery stenosis were randomly assigned in a 1:1 ratio to receive carotid artery stenting or carotid endarterectomy. Randomisation was by telephone call or fax to a central computerised service and was stratified by centre with minimisation for sex, age, contralateral occlusion, and side of the randomised artery. Patients and investigators were not masked to treatment assignment. Patients were followed up by independent clinicians not directly involved in delivering the randomised treatment. The primary outcome measure of the trial is the 3-year rate of fatal or disabling stroke in any territory, which has not been analysed yet. The main outcome measure for the interim safety analysis was the 120-day rate of stroke, death, or procedural myocardial infarction. Analysis was by intention to treat (ITT). This study is registered, number ISRCTN25337470. Findings The trial enrolled 1713 patients (stenting group, n=855; endarterectomy group, n=858). Two patients in the stenting group and one in the endarterectomy group withdrew immediately after randomisation, and were not included in the ITT analysis. Between randomisation and 120 days, there were 34 (Kaplan-Meier estimate 4·0%) events of disabling stroke or death in the stenting group compared with 27 (3·2%) events in the endarterectomy group (hazard ratio [HR] 1·28, 95% CI 0·77–2·11). The incidence of stroke, death, or procedural myocardial infarction was 8·5% in the stenting group compared with 5·2% in the endarterectomy group (72 vs 44 events

  18. Distal 'buddy-in-jail' technique: a complementary 'Jail with stent' method for stent delivery.

    PubMed

    Dangoisse, Vincent; Guédès, Antoine; Schroëder, Erwin

    2014-03-01

    Delivery of coronary stents can be challenging, but the use of a second or 'buddy' wire helps the progression of equipment through tortuous and rigid vessels. We successfully positioned a coronary stent in a distal lesion, intentionally jailing the buddy wire during stent delivery. The jailed wire was then used to proceed further with proximal coronary stenting. We report 10 cases using either the jailed or the non-jailed wire for this modified 'buddy-in-jail' technique.

  19. One year cost effectiveness of sirolimus eluting stents compared with bare metal stents in the treatment of single native de novo coronary lesions: an analysis from the RAVEL trial

    PubMed Central

    van Hout, B A; Serruys, P W; Lemos, P A; van den Brand, M J B M; Es, G-A van; Lindeboom, W K; Morice, M-C

    2005-01-01

    Objective: To assess the balance between costs and effects of the sirolimus eluting stent in the treatment of single native de novo coronary lesions in the RAVEL (randomised study with the sirolimus eluting Bx Velocity balloon expandable stent in the treatment of patients with de novo native coronary artery lesions) study. Design: Multicentre, double blind, randomised trial Setting: Percutaneous coronary intervention for single de novo coronary lesions Patients: 238 patients with stable or unstable angina. Interventions: Randomisation to sirolimus eluting stent or bare stent implantation. Main outcome measures: Patients were followed up to one year and the treatment effects were expressed as one year survival free of major adverse cardiac events (MACE). Costs were estimated as the product of resource utilisation and Dutch unit costs. Results: At one year, the absolute difference in MACE-free survival was 23% in favour of the sirolimus eluting stent group. At the index procedure, sirolimus eluting stent implantation had an estimated additional procedural cost of €1286. At one year, however, the estimated additional cost difference had decreased to €54 because of the reduction in the need for repeat revascularisations in the sirolimus group (0.8% v 23.6%; p < 0.01). After adjustment of actual results for the consequences of angiographic follow up (correction based on data from the BENESTENT (Belgium Netherlands stent) II study), the difference in MACE-free survival was estimated at 11.1% and the additional one year costs at €166. Conclusions: The one year data from RAVEL suggest an attractive balance between costs and effects for sirolimus eluting stents in the treatment of single native de novo coronary lesions. The cost effectiveness of drug eluting stents in more complex lesion subsets remains to be determined. PMID:15772214

  20. Anchor technique: Use of stent retrievers as an anchor to advance thrombectomy catheters in internal carotid artery occlusions

    PubMed Central

    Wolfe, Stacey Q; Janjua, Rashid M; Hedayat, Hirad; Burnette, Christofer

    2015-01-01

    In three recent cases of acute complete internal artery occlusions, we used stent retriever deployed through the mechanical aspiration/distal access catheters to achieve recanalization. In all cases the stent retriever was used as an anchor and supplemented mechanical thrombectomy. This report describes the technical details of the procedure and presents an alternative plan of action in difficult cases when standard thrombectomy techniques do not work. PMID:26494404

  1. Angioplasty or Stenting in Adult Coarctation of the Aorta? A Retrospective Single Center Analysis Over a Decade

    SciTech Connect

    Macdonald, Sumaira Thomas, Steven M.; Cleveland, Trevor J.; Gaines, Peter A.

    2003-08-15

    For over 11 years, endovascular treatment by angioplasty (PTA) alone or stenting of adult coarctation at a single center was evaluated. We retrospectively reviewed 28 consecutive patients (31 interventions), median age 25 years, treated between 1991 and 2002, 20 of whom had native coarctation. Thirteen patients had PTA alone (16 procedures) (10 'kissing balloon' angioplasty comprising 12 interventions, and 3 single balloon angioplasty comprising 4 interventions) and 15 patients were stented(15 procedures), including 6 secondary and 9 primary stents. There were no procedural or 30-day complications. For the whole group, the median follow-up was 6.6 years (range 1-10 years). In the PTA group, median follow-up was 9 years (range 3-10) and in the stenting group it was 3 years (range 1-5). There were 9 restenoses in the PTA group (6 after 'kissing balloons' and 3 after single balloon) comprising 56% of the angioplasties (9/16 procedures). There was 1 restenosis in the stenting group diagnosed at computed tomography (CT). The patient was clinically well. For the whole group there were significant reductions in systolic blood pressure (BP) (p 0.0003), diastolic BP (p = 0.004) and number of drugs per patient (p = 0.045) at latest follow-up post-treatment. Five patients discontinued therapy.Analysis of the groups revealed that the reduction of systolic and diastolic BP and number of drugs did not reach statistical significance in the PTA group but were significant in the stent group. The endovascular management of adult coarctation is safe. Stents may be more effective than PTA alone but longer-term follow-up of stents is required.

  2. Prevention of stent thrombosis: challenges and solutions

    PubMed Central

    Reejhsinghani, Risheen; Lotfi, Amir S

    2015-01-01

    Stent thrombosis is an uncommon but serious complication which carries with it significant mortality and morbidity. This review analyzes the entity of stent thrombosis from a historical and clinical perspective, and chronicles the evolution of this condition through the various generations of stent development, from bare metal to first-generation, second-generation, and third-generation drug-eluting stents. It also delineates the specific risk factors associated with stent thrombosis and comprehensively examines the literature related to each of these risks. Finally, it highlights the preventative strategies that can be garnered from the existing data, and concludes that a multifactorial approach is necessary to combat the occurrence of stent thrombosis, with higher risk groups, such as patients with ST segment elevation myocardial infarction, meriting further research. PMID:25657588

  3. Rapid Virtual Stenting for Intracranial Aneurysms

    PubMed Central

    Zhao, Liang; Chen, Danyang; Chen, Zihe; Wang, Xiangyu; Paliwal, Nikhil; Xiang, Jianping; Meng, Hui; Corso, Jason J.; Xu, Jinhui

    2016-01-01

    The rupture of Intracranial Aneurysms is the most severe form of stroke with high rates of mortality and disability. One of its primary treatments is to use stent or Flow Diverter to divert the blood flow away from the IA in a minimal invasive manner. To optimize such treatments, it is desirable to provide an automatic tool for virtual stenting before its actual implantation. In this paper, we propose a novel method, called ball-sweeping, for rapid virtual stenting. Our method sweeps a maximum inscribed sphere through the aneurysmal region of the vessel and directly generates a stent surface touching the vessel wall without needing to iteratively grow a deformable stent surface. Our resulting stent mesh has guaranteed smoothness and variable pore density to achieve an enhanced occlusion performance. Comparing to existing methods, our technique is computationally much more efficient. PMID:27346910

  4. Rapid virtual stenting for intracranial aneurysms

    NASA Astrophysics Data System (ADS)

    Zhao, Liang; Chen, Danyang; Chen, Zihe; Wang, Xiangyu; Paliwal, Nikhil; Xiang, Jianping; Meng, Hui; Corso, Jason J.; Xu, Jinhui

    2016-03-01

    The rupture of Intracranial Aneurysms is the most severe form of stroke with high rates of mortality and disability. One of its primary treatments is to use stent or Flow Diverter to divert the blood flow away from the IA in a minimal invasive manner. To optimize such treatments, it is desirable to provide an automatic tool for virtual stenting before its actual implantation. In this paper, we propose a novel method, called ball-sweeping, for rapid virtual stenting. Our method sweeps a maximum inscribed sphere through the aneurysmal region of the vessel and directly generates a stent surface touching the vessel wall without needing to iteratively grow a deformable stent surface. Our resulting stent mesh has guaranteed smoothness and variable pore density to achieve an enhanced occlusion performance. Comparing to existing methods, our technique is computationally much more efficient.

  5. [Intracoronary ultrasound: A necessary tool for stent implantation? Arguments in favor].

    PubMed

    Botas, J

    1999-06-01

    Intracoronary ultrasound (ICUS), as opposed to angiography, provides high resolution, tomographic images of the coronary vessel and lumen. Because of its superior diagnostic sensitivity ICUS is indicated in the evaluation of suboptimal results and complications following stent implantation. Only a few years ago the use of stents was limited by a high incidence of subacute thrombosis. ICUS demonstrated that the deployment technique used at that time was inadequate and that stent expansion could be improved by the routine use of high pressure inflation, leading to a simplification in the anticoagulation regimen and a decrease in the subacute thrombosis rate in elective procedures to < or = 1%. However, the routine use of high balloon pressures does not assure an adequate expansion of the stent. Only about one third of the stents deployed under angiographic guidance are optimally expanded, with intra-stent luminal dimensions similar to the adjacent, reference, luminal sizes. Significantly, these underdeployed stents can be recognized by ICUS and a large proportion adequately expanded. It should be emphasized that the best predictors of stent restenosis are two ICUS parameters, the postprocedural luminal dimensions and the % cross sectional narrowing, and not the angiographic parameters. Likewise, two of the lowest restenosis rates ever reported (12.8% and 7.3%) have occurred in two studies (WEST-2 and MUSIC) in which stent deployment was guided by ICUS. Two trials (AVID and OPTICUS) have been specifically designed to test the hypothesis that routine use of ICUS to guide stent implantation could diminish the restenosis rate, but their final results are not yet available. The CRUISE study was designed to evaluate the impact of routine ICUS not on angiographic restenosis but on the clinical need of revascularization. In this trial, the larger luminal dimensions of the stents implanted under ICUS guidance translated into a 40% reduction in the 6 month revascularization

  6. Acute Duodenal Obstruction After Percutaneous Placement of Metallic Biliary Stents: Peroral Treatment with Enteral Stents

    SciTech Connect

    Lopera, Jorge E. Alvarez, Oscar A.; Perdigao, Joseph; Castaneda-Zuniga, Wilfrido

    2003-09-15

    Three patients with malignant biliary obstruction were treated with placement of metallic biliary stents. Two patients had known partial duodenal stenosis but had no symptoms of gastrointestinal obstruction. The patients developed symptomatic duodenal obstruction early after biliary metallic stent placement. The symptomatic duodenal obstructions were successfully treated with peroral placement of duodenal stents, which obviated the need for surgical intervention.

  7. Mechanical behavior of peripheral stents and stent-vessel interaction: A computational study

    NASA Astrophysics Data System (ADS)

    Dottori, Serena; Flamini, Vittoria; Vairo, Giuseppe

    2016-05-01

    In this paper stents employed to treat peripheral artery disease are analyzed through a three-dimensional finite-element approach, based on a large-strain and large-displacement formulation. Aiming to evaluate the influence of some stent design parameters on stent mechanics and on the biomechanical interaction between stent and arterial wall, quasi-static and dynamic numerical analyses are carried out by referring to computational models of commercially and noncommercially available versions of both braided self-expandable stents and balloon-expandable stents. Addressing isolated device models, opening mechanisms and flexibility of both opened and closed stent configurations are numerically experienced. Moreover, stent deployment into a stenotic peripheral artery and possible postdilatation angioplasty (the latter for the self-expandable device only) are simulated by considering different idealized vessel geometries and accounting for the presence of a stenotic plaque. Proposed results highlight important differences in the mechanical response of the two types of stents, as well as a significant influence of the vessel shape on the stress distributions arising upon the artery-plaque system. Finally, computational results are used to assess both the stent mechanical performance and the effectiveness of the stenting treatment, allowing also to identify possible critical conditions affecting the risk of stent fracture, tissue damage, and/or pathological tissue response.

  8. Feasibility and Safety of Transradial Arterial Approach for Simultaneous Right and Left Vertebral Artery Angiographic Studies and Stenting

    SciTech Connect

    Yip, H.-K.; Youssef, Ali A.; Chang, W.-N.; Lu, C.-H.; Yang, C.-H.; Chen, S.-M.; Wu, C.-J.

    2007-09-15

    Objectives. This study investigated whether the transradial artery (TRA) approach using a 6-French (F) Kimny guiding catheter for right vertebral artery (VA) angiographic study and stenting is safe and effective for patients with significant VA stenosis. Background. The TRA approach is commonly performed worldwide for both diagnostic cardiac catheterization and catheter-based coronary intervention. However, to our knowledge, the safety and feasibility of left and right VA angiographic study and stenting, in the same procedure, using the TRA approach for patients with brain ischemia have not been reported. Methods. The study included 24 consecutive patients (22 male, 2 female; age, 63-78 years). Indications for VA angiographic study and stenting were (1) prior stroke or symptoms related to vertebrobasilar ischemia and (2) an asymptomatic but vertebral angiographic finding of severe stenosis (>70%). A combination of the ipsilateral and retrograde-engagement technique, which involved a looping 6-F Kimny guiding catheter, was utilized for VA angiographic study. For VA stenting, an ipsilateral TRA approach with either a Kimny guiding catheter or a left internal mammary artery guiding catheter was utilized in 22 patients and retrograde-engagement technique in 2 patients. Results. A technically successful procedure was achieved in all patients, including left VA stenting in 15 patients and right VA stenting in 9 patients. The mean time for stenting (from engagement to stent deployment) was 12.7 min. There were no vascular complications or mortality. However, one patient suffered from a transient ischemic attack that resolved within 3 h. Conclusion. We conclude that TRA access for both VA angiographic study and VA stenting is safe and effective, and provides a simple and useful clinical tool for patients unsuited for femoral arterial access.

  9. Peripheral Stent Placement in Hemodialysis Grafts

    SciTech Connect

    Kariya, Shuji Tanigawa, Noboru; Kojima, Hiroyuki; Komemushi, Atsushi; Shomura, Yuzo; Shiraishi, Tomokuni; Kawanaka, Toshiaki; Sawada, Satoshi

    2009-09-15

    The purpose of the present study was to evaluate the clinical outcome of peripheral stent placement after failed balloon angioplasty in patients with grafts who are on hemodialysis. We examined 30 Wallstents that were placed in 26 patients because balloon angioplasty failed or early restenosis (<3 months) occurred within 3 months. We retrospectively reviewed 267 consecutive balloon angioplasties performed in 71 patients with graft access between August 2000 and March 2007. Stent placements accounted for 30 (11.2%) of the 267 balloon angioplasties. The clinical success rate of stent placement was 93.3% (28 of 30 stent placements). The 3-, 6-, and 12-month primary patency rates were 73.3%, 39.3%, and 17.7%, respectively. The 1-, 2-, and 3-year secondary patency rates were 90.2%, 83.8%, and 83.8%, respectively. Primary patency was significantly prolonged by stent placement after early restenosis compared with previous balloon angioplasty alone (P = 0.0059). Primary patency after stent placement was significantly lower than after successful balloon angioplasty without indications for stent placement (P = 0.0279). Secondary patency rates did not significantly differ between stent placement and balloon angioplasty alone. The mean number of reinterventions required to maintain secondary patency after stent placement was significantly larger than that after balloon angioplasty alone (Mann-Whitney U test, P = 0.0419). We concluded that peripheral stent placement for graft access is effective for salvaging vascular access after failed balloon angioplasty and for prolonging patency in early restenosis after balloon angioplasty. However, reinterventions are required to maintain secondary patency after stent placement. Furthermore, peripheral stent placement for graft access cannot achieve the same primary patency as balloon angioplasty alone.

  10. Stent implantation influence wall shear stress evolution

    NASA Astrophysics Data System (ADS)

    Bernad, S. I.; Totorean, A. F.; Bosioc, A. I.; Petre, I.; Bernad, E. S.

    2016-06-01

    Local hemodynamic factors are known affect the natural history of the restenosis critically after coronary stenting of atherosclerosis. Stent-induced flows disturbance magnitude dependent directly on the strut design. The impact of flow alterations around struts vary as the strut geometrical parameters change. Our results provide data regarding the hemodynamic parameters for the blood flow in both stenosed and stented coronary artery under physiological conditions, namely wall shear stress and pressure drop.

  11. One year clinical outcomes of renal artery stenting: the results of ODORI Registry.

    PubMed

    Sapoval, M; Tamari, I; Goffette, P; Downes, M; Senechal, Q; Fanelli, F; Reimer, P; Negaiwi, Z; De Cassin, P; Heye, S; Korobov, V; Tsetis, D; Abada, H

    2010-06-01

    The safety, efficacy and long term clinical benefits of renal artery revascularization by stenting are still a matter of debate. The aim of our study was to define the safety and efficacy of renal artery stenting with the Tsunami peripheral stent (Terumo Corporation, Tokyo, Japan). The ODORI was a prospective, multicentre registry which enrolled 251 consecutive patients, (276 renal arteries) in 36 centres across Europe. The primary endpoint was acute procedural success defined as <30% residual stenosis after stent placement. Secondary endpoints included major adverse events, blood pressure control, serum creatinine level, and target lesion revascularization (TLR) at 6 and 12 months. Patients were 70 +/- 10 years old, 59% were male, 33% had diabetes, and 96% hypertension. The main indications for renal stent implantation were hypertension in 83% and renal salvage in 39%. Direct stent implantation was performed in 76% of the cases. Acute success rate was 100% with residual stenosis of 2.5 +/- 5.4%. Systolic/diastolic blood pressure decreased from a mean of 171/89 at baseline to 142/78 mmHg at 6 months (p < 0.0001 vs. baseline), and 141/80 mmHg at 12 months (p < 0.0001 vs. baseline). Mean serum creatinine concentration did not change significantly in the total population. However, there was significant improvement in the highest tercile (from 283 micromol/l at baseline to 205 and 209 micromol/l at 6 and 12 months respectively). At 12-months, rates of restenosis and TLR were 6.6 and 0.8% respectively. The 12 month cumulative rate of all major clinical adverse events was 6.4% while the rate of device or procedure related events was 2.4%. In hypertensive patients with atherosclerotic renal artery stenosis Tsunami peripheral balloon-expandable stent provides a safe revascularization strategy, with a potential beneficial impact on hypertension control and renal function in the highest risk patients.

  12. One Year Clinical Outcomes of Renal Artery Stenting: The Results of ODORI Registry

    SciTech Connect

    Sapoval, M.; Tamari, I.; Goffette, P.; Downes, M.; Senechal, Q.; Fanelli, F.; Reimer, P.; Negaiwi, Z.; Cassin, P. De; Heye, S.; Korobov, V.; Tsetis, D.; Abada, H.

    2010-06-15

    The safety, efficacy and long term clinical benefits of renal artery revascularization by stenting are still a matter of debate. The aim of our study was to define the safety and efficacy of renal artery stenting with the Tsunami peripheral stent (Terumo Corporation, Tokyo, Japan). The ODORI was a prospective, multicentre registry which enrolled 251 consecutive patients, (276 renal arteries) in 36 centres across Europe. The primary endpoint was acute procedural success defined as <30% residual stenosis after stent placement. Secondary endpoints included major adverse events, blood pressure control, serum creatinine level, and target lesion revascularization (TLR) at 6 and 12 months. Patients were 70 {+-} 10 years old, 59% were male, 33% had diabetes, and 96% hypertension. The main indications for renal stent implantation were hypertension in 83% and renal salvage in 39%. Direct stent implantation was performed in 76% of the cases. Acute success rate was 100% with residual stenosis of 2.5 {+-} 5.4%. Systolic/diastolic blood pressure decreased from a mean of 171/89 at baseline to 142/78 mmHg at 6 months (p < 0.0001 vs. baseline), and 141/80 mmHg at 12 months (p < 0.0001 vs. baseline). Mean serum creatinine concentration did not change significantly in the total population. However, there was significant improvement in the highest tercile (from 283 {mu}mol/l at baseline to 205 and 209 {mu}mol/l at 6 and 12 months respectively). At 12-months, rates of restenosis and TLR were 6.6 and 0.8% respectively. The 12 month cumulative rate of all major clinical adverse events was 6.4% while the rate of device or procedure related events was 2.4%. In hypertensive patients with atherosclerotic renal artery stenosis Tsunami peripheral balloon-expandable stent provides a safe revascularization strategy, with a potential beneficial impact on hypertension control and renal function in the highest risk patients.

  13. Nitinol stent design - understanding axial buckling.

    PubMed

    McGrath, D J; O'Brien, B; Bruzzi, M; McHugh, P E

    2014-12-01

    Nitinol׳s superelastic properties permit self-expanding stents to be crimped without plastic deformation, but its nonlinear properties can contribute towards stent buckling. This study investigates the axial buckling of a prototype tracheobronchial nitinol stent design during crimping, with the objective of eliminating buckling from the design. To capture the stent buckling mechanism a computational model of a radial force test is simulated, where small geometric defects are introduced to remove symmetry and allow buckling to occur. With the buckling mechanism ascertained, a sensitivity study is carried out to examine the effect that the transitional plateau region of the nitinol loading curve has on stent stability. Results of this analysis are then used to redesign the stent and remove buckling. It is found that the transitional plateau region can have a significant effect on the stability of a stent during crimping, and by reducing the amount of transitional material within the stent hinges during loading the stability of a nitinol stent can be increased.

  14. Auxetic oesophageal stents: structure and mechanical properties.

    PubMed

    Ali, Murtaza Najabat; Busfield, James J C; Rehman, Ihtesham U

    2014-02-01

    Oesophageal cancer is the ninth leading cause of malignant cancer death and its prognosis remains poor, ranking as the sixth most frequent cause of death in the world. This research work aims to adopt an Auxetic (rotating-squares) geometry device, that had previously been examined theoretically and analysed by Grima and Evans (J Mater Sci Lett 19(17):1563-1565, 2000), to produce a novel Auxetic oesophageal stent and stent-grafts relevant to the palliative treatment of oesophageal cancer and also for the prevention of dysphagia. This paper discusses the manufacture of a small diameter Auxetic oesophageal stent and stent-graft. The oral deployment of such an Auxetic stent would be simplest if a commercial balloon dilatational catheter was used as this obviates the need for an expensive dedicated delivery system. A novel manufacturing route was employed in this research to develop both Auxetic films and Auxetic oesophageal stents, which ranged from conventional subtractive techniques to a new additive manufacturing method. Polyurethane was selected as a material for the fabrication of Auxetic films and Auxetic oesophageal stents because of its good biocompatibility and non-toxicological properties. The Auxetic films were later used for the fabrication of seamed Auxetic oesophageal stents. The flexible polyurethane tubular grafts were also attached to the inner luminal side of the seamless Auxetic oesophageal stents, in order to prevent tumour in-growth. Scanning electron microscopy was used to conduct surface morphology study by using different Auxetic specimens developed from different conventional and new additive manufacturing techniques. Tensile testing of the Auxetic films was performed to characterise their mechanical properties. The stent expansion tests of the Auxetic stents were done to analyse the longitudinal extension and radial expansion of the Auxetic stent at a range of radial pressures applied by the balloon catheter, and to also identify the pressure

  15. Silicone-covered biodegradable magnesium-stent insertion in the esophagus: a comparison with plastic stents

    PubMed Central

    Zhu, Yue-Qi; Yang, Kai; Edmonds, Laura; Wei, Li-Ming; Zheng, Reila; Cheng, Ruo-Yu; Cui, Wen-Guo; Cheng, Ying-Sheng

    2016-01-01

    Background: We determined the feasibility of, and tissue response to silicone-covered biodegradable magnesium- and plastic-stent insertion into the esophagus in rabbits. Methods: The mechanical compression–recovery characteristics and degradation behaviors of the magnesium stent were investigated in vitro. A total of 45 rabbits were randomly divided into a magnesium- (n = 15) and a plastic- (n = 15) stent group, and underwent stent insertion into the lower third of the esophagus under fluoroscopic guidance; a control group (n = 15) did not undergo the intervention. Esophagography was performed at 1, 2, and 4 weeks. Five rabbits in each group were euthanized at each time point for histological examination. Results: Silicone-covered magnesium stents showed similar radial force to plastic stents (p > 0.05). The magnesium stents degraded rapidly in an acidic solution, but 90.2% ± 3.1% of the residual mass was maintained after a 2-week degradation in a solution with a pH of 4.0. All stent insertions were well tolerated. Magnesium stents migrated in six rabbits (one at 1 week, one at 2 weeks and four at 4 weeks), and plastic stents migrated in three rabbits (one at 2 weeks and two at 4 weeks; p > 0.05). Esophageal wall remodeling (thinner epithelial and smooth muscle layers) was similar in both stented groups (p > 0.05), and the esophagus wall was found to be significantly thinner in the stented groups than in the control group (p < 0.05). Esophageal injury and collagen deposition following stent insertion were similar and did not differ from the control group (p > 0.05). Conclusions: Esophageal silicone-covered magnesium stents provided reliable support for at least 2 weeks, with acceptable migration rates and without causing severe injury or tissue reaction compared with plastic stents. PMID:28286555

  16. Neointimal Hyperplasia in Low-Profile Nitinol Stents, Palmaz Stents, and Wallstents: A Comparative Experimental Study

    SciTech Connect

    Schuermann, Karl; Vorwerk, Dierk; Kulisch, Arthur; Stroehmer-Kulisch, Eva; Biesterfeld, Stefan; Stopinski, Tadeusz; Guenther, Rolf W.

    1996-04-15

    Purpose: To compare neointima formation following insertion of low-profile Nitinol stents, Palmaz stents, and Wallstents. Methods: Nitinol stents, Palmaz stents, and Wallstents similar in size were transfemorally inserted into the iliac arteries of 12 sheep. Four stents per sheep were deployed; the position of the stents was varied so that each type of stent was placed in each position (right or left, proximal or distal) with equal frequency. Stent patency was followed by angiography. Six sheep were euthanized after 1 month, and the remaining six after 6 months. Iliac arteries were removed en bloc and prepared for histological examination. Neointimal and medial thickness were measured by light microscopy, and measurements were analyzed statistically. Results: Mean neointimal thickness both over (NO) and between (NB) the stent struts was greater in Wallstents (NO = 0.341 mm, NB = 0.368 mm) than in the Nitinol (NO = 0.260 mm, NB = 0.220 mm) and Palmaz stents (NO = 0.199 mm, NB = 0.204 mm), but differences were not significant (p> 0.05). Medial atrophy in the area between the stent struts was greater in Wallstents compared with Nitinol and Palmaz stents (p < 0.007 and p < 0.02, respectively); in the area under the stent struts there was a significant difference only between Palmaz stents and Wallstents (p < 0.02). Conclusion: Under defined experimental conditions, none of the three types of stent appears to be preferable to the others regarding neointima formation in the short- to mid-term follow-up period.

  17. Angioplasty and Stenting of Symptomatic Vertebral Artery Stenosis

    PubMed Central

    Mohammadian, R.; Sharifipour, E.; Mansourizadeh, R.; Sohrabi, B.; Nayebi, A.R; Haririan, S.; Farhoudi, M.; Charsouei, S.; Najmi, S.

    2013-01-01

    Summary Percutaneous transluminal angioplasty (PTA) has recently become a noteworthy treatment option for significant stenosis involving the vertebral artery (VA) in selected patients. We conducted a prospective study to evaluate the efficacy, safety and mid-term follow up results of 206 cases received PTA with or without stent implant to treat their symptomatic atherosclerotic VA stenosis in all segments (V1-V4). In a prospective mono-arm trial from October 2008 to July 2012 in a single center, 239 lesions affecting the intra or extracranial VA (171 in V1, 17 in V2, 14 in V3, 21 in V4 and 16 in combined segments) were treated by PTA with or without stent implant. Non-disabling stroke patients who had failed conservative medical treatment and had angiographic evidence of >50% stenosis in the dominant VA with clinical signs and symptoms of VB stenosis were included in this study. They were mean followed for 13.15±5.24 months after treatment. Overall, 206 patients underwent the procedure. A stent was implemented in 199 patients (96.6%). The periprocedural complication rate was 7.2%. The procedural (technical) success rate was 97.6%. Of the total 239 lesions, 223 were treated with stent implant. Clinical success was achieved in all 206 symptomatic patients after the procedure. Restenosis occurred in 15.9% after a mean 10.8 (6-24) months. Of those, 63.1% and 34.2% had mild and moderate stenosis that was treated medically, whereas one case (2.6%) with severe restenosis underwent balloon angioplasty. No deaths occurred during the follow-up period. The follow-up complication rate was 6.3%. TIA occurred in 4.4%, a minor stroke in 1.4% and a major stroke in one patient. The overall patient event-free survival was 92.4%. These results demonstrate the safety and feasibility of PTA with or without stent implant, with a high technical success rate, a low complication rate, a low restenosis rate and durable clinical success in patients with symptomatic VA stenosis. This

  18. Iliocaval Fistula Presenting with Paradoxical Pulmonary Embolism Combined with High-Output Heart Failure Successfully Treated by Endovascular Stent-Graft Repair: Case Report

    PubMed Central

    Na, Soo Jin; Kim, Tae-Hoon; Park, Sun-Chul; Shin, Woo-Seung; Chun, Ho-Jong; Lee, Jong-Min

    2014-01-01

    A 51-yr-old man presented exertional dyspnea as a consequence of iliocaval fistula combined with paradoxical pulmonary embolism and high-output heart failure. Endovascular stent-graft repair was performed to cover iliocaval fistula and restore the heart function. After the procedure, dyspnea was improved and procedure related complication was not seen. A 6-month follow-up computed tomography showed regression of pulmonary thromboembolism and well-positioned stent-graft without graft migration, aortacaval communication or endoleak. Stent graft implantation should be considered an alternative of open repair surgery for treament of abdominal arteriovenous fisula, especially in patient with high risk for surgery. PMID:24550662

  19. First successful implantation of a biodegradable metal stent into the left pulmonary artery of a preterm baby.

    PubMed

    Zartner, Peter; Cesnjevar, Robert; Singer, Helmut; Weyand, Michael

    2005-12-01

    Stent implantation in the youngest patients with a congenital heart disease implicates limitations concerning further vessel growth, the need of staged redilation, and later surgical removal. The search to overcome these restrictions led to open stent designs, with a wide adaptability to the vessel growth and recently to the development of bioabsorbable stent materials. A preterm baby born at 26 weeks of gestation was referred to our clinic following inadvertent ligation of the left pulmonary artery. Despite efficient debanding, the left lung perfusion was absent. Implantation of a biodegradable 3 mm magnesium stent was performed in a hybrid procedure when the baby weighed 1.7 kg. Reperfusion of the left lung was established and persisted throughout the 4-month follow-up period during which the gradual degradation process of the stent completed. Additional interventions, should they become necessary, seem not to be limited. Despite the small size of the baby, the degradation process was clinically well tolerated. The mechanical and degradation characteristics of the magnesium stent proved to be adequate to secure reperfusion of the previously occluded left pulmonary artery. Bioabsorbable stents with different diameters may help develop new strategies in the therapy of vessel stenosis in pediatric patients.

  20. Left main coronary artery stenosis treatment with two paclitaxel-eluting stents in a patient with cardiac allograft vasculopathy.

    PubMed

    Martínez-Ríos, Marco A; Méndez-Ortíz, Arturo; Gaspar, Jorge; Barragán-García, Rodolfo; Fernández-de-la-Reguera, Guillermo; González-Quesada, Carlos J

    2008-01-01

    Cardiac transplantation is a well defined therapy for end stage heart failure. After the first year of transplantation, allograft coronary artery disease (ACAD) is the second main cause of death. The ACAD is defined as a diffuse process affecting the entire length of epicardial vessels. Once ACAD has been established, treatments such as coronary angioplasty, coronary stenting, and coronary bypass are performed. We present a case of successful stenting of the left main coronary artery (LMCA) in a patient with ACAD. The patient's medical history was significant for heart transplantation due to ischemic heart failure. Four years after transplantation the patient was admitted again due to sudden worsening of New York Heart Association functional class and extreme fatigue. Coronary angiogram showed a severe stenosis in the proximal segment of the LMCA; we performed stenting with a paclitaxel-eluting stent (PES). Six months after the procedure, the patient had an elective angiogram, where we discovered a new severe occlusion distally to the former stent; a second PES was implanted. Fourteen months after the second stenting, a new elective angiogram was performed without evidence of in-stent restenosis. After a 8-year follow-up since transplantation, the patient is free from dyspnea, angina, and adverse cardiovascular events. Our report suggests the efficacy of PES as ACAD treatment of the unprotected LMCA.

  1. Evaluation of the compressive mechanical properties of endoluminal metal stents.

    PubMed

    Schrader, S C; Beyar, R

    1998-06-01

    The mechanical properties of metal stents are important parameters in the consideration of stent design, matched to resist arterial recoil and vascular spasm. The purpose of this study was to develop a system for a standardized quantitative evaluation of the mechanical characteristics of various coronary stents. Several types of stents were compressed by external hydrostatic pressure. The stent diameter was assessed by placing a pair of small ultrasonic sono-crystals on the stent. From pressure-strain diagrams the ultimate strength and radial stiffness for each stent were determined. For all stents, except the MICRO-II and the Wiktor stent, the diameter decreased homogeneously until an ultimate compressive strength was exceeded, causing an abrupt collapse. Expanded to 3 mm, the mechanical behavior of the beStent, the Crown and the Palmaz-Schatz stent (PS153-series) were comparable. The spiral articulated Palmaz-Schatz stent showed twice the strength (1.26 atm) of the PS-153 (0.65 atm). The NIR stent yielded a maximum strength of 1.05 atm. The MICRO-II and the Wiktor stent did not collapse abruptly but rather showed a continuous decline of diameter with increasing external pressure. The Cardiocoil stent behaved in a fully elastic manner and showed the largest radial stiffness. Difference in mechanical properties between stents were documented using a new device specifically developed for that purpose. These mechanical stent parameters may have important clinical implications.

  2. Initial experience with paclitaxel-coated stents.

    PubMed

    Grube, Eberhard; Büllesfeld, Lutz

    2002-12-01

    Local delivery of immunosuppressive or antiproliferative agents using a drug-eluting stent is a new technology that is supposed to inhibit in-stent restenosis, thus providing a biological and mechanical solution. This technique is a very promising. To date, several agents have been used, including paclitaxel, QP-2, rapamycin, actinomycin D, dexamethason, tacrolimus, and everolimus. Several studies, published recently or still ongoing, have evaluated these drugs as to their release kinetics, effective dosage, safety in clinical practice, and benefit. These studies include: SCORE (paclitaxel derivative), TAXUS I-VI, ELUTES, ASPECT, DELIVER (paclitaxel), RAVEL, SIRIUS (sirolimus), ACTION (actinomycin), EVIDENT, PRESENT (tacrolimus), EMPEROR (dexamethason), and FUTURE (everolimus). Paclitaxel was one of the first stent-based antiproliferative agents under clinical investigation that provided profound inhibition of neointimal thickening depending on delivery duration and drug dosage. The randomized, multicenter SCORE trail (Quanam stent, paclitaxel-coated) enrolled 266 patients at 17 sites. At 6-month's follow-up, a drop of 83% in stent restenosis using the drug-eluting stent could be achieved (6.4% drug-eluting stent vs 36.9% control group), which was attributable to a remarkable decrease in intimal proliferation. Unfortunately, due to frequent stent thrombosis and side-branch occlusions, the reported 30-day MACE rate was 10.2%. The randomized TAXUS-I safety trial (BSC, NIRx, paclitaxel-coated) also demonstrated beneficial reduction of restenotic lesions at 6-month's follow-up (0% vs 10%) but was associated with the absence of thrombotic events presumably due to less drug dosage. The ongoing TAXUS II-VI trials are addressing additional insight regarding the efficacy of the TAXUS paclitaxel-eluting stent. ASPECT and ELUTES evaluated paclitaxel-coated stents (i.e., Cook and Supra G), including subgroups with different drug dosages. With respect to stent restenosis and

  3. Effect of endovascular stenting of right ventricle to pulmonary artery conduit stenosis in infants with hypoplastic left heart syndrome on stage II outcomes.

    PubMed

    Gray, Robert G; Minich, L Luann; Weng, Hsin Yi; Heywood, Mason C; Burch, Phillip T; Cowley, Collin G

    2012-07-01

    There is growing awareness that the Norwood procedure with the Sano modification is prone to early right ventricular to pulmonary artery (RV-PA) conduit stenosis resulting in systemic oxygen desaturation, increased interstage morbidity, and death. We report our experience with endovascular stent placement for conduit stenosis and compare the outcomes at stage II surgery between stented and nonstented infants. The medical records of all patients with hypoplastic left heart syndrome who received an RV-PA conduit at Norwood palliation from May 2005 to January 2010 were reviewed. The preoperative anatomy, demographics, operative variables, and outcomes pertaining to the Norwood and subsequent stage II surgeries were obtained and compared between stented and nonstented infants. The pre- and post-stent oxygen saturation, stenosis location, type and number of stents implanted, concomitant interventions, procedure-related complications, and reinterventions were collected. Of the 66 infants who underwent the Norwood procedure with RV-PA conduit modification, 16 (24%) received stents. The anatomy, demographics, and outcome variables after the Norwood procedure were similar between the stented and nonstented infants. The age at catheterization was 93 ± 48 days, and the weight was 4.9 ± 1.2 kg. The oxygen saturation increased from 66 ± 9% before intervention to 82 ± 6% immediately after stenting (p <0.0001). No interstage surgical shunt revisions were performed in either group. Age, weight, pre-stage II echocardiographic variables, oxygen saturation, and operative and outcome variables, including mortality, were similar between the 2 groups. In conclusion, endovascular stent placement for RV-PA conduit stenosis after the Norwood procedure leads to improved systemic oxygen levels and prevents early performance of stage II surgery without compromising stage II outcomes.

  4. Bioresorbable ureteral stents from natural origin polymers.

    PubMed

    Barros, Alexandre A; Rita, Ana; Duarte, C; Pires, Ricardo A; Sampaio-Marques, Belém; Ludovico, Paula; Lima, Estevão; Mano, João F; Reis, Rui L

    2015-04-01

    In this work, stents were produced from natural origin polysaccharides. Alginate, gellan gum, and a blend of these with gelatin were used to produce hollow tube (stents) following a combination of templated gelation and critical point carbon dioxide drying. Morphological analysis of the surface of the stents was carried out by scanning electron microscopy. Indwelling time, encrustation, and stability of the stents in artificial urine solution was carried out up to 60 days of immersion. In vitro studies carried out with simulated urine demonstrated that the tubes present a high fluid uptake ability, about 1000%. Despite this, the materials are able to maintain their shape and do not present an extensive swelling behavior. The bioresorption profile was observed to be highly dependent on the composition of the stent and it can be tuned. Complete dissolution of the materials may occur between 14 and 60 days. Additionally, no encrustation was observed within the tested timeframe. The ability to resist bacterial adherence was evaluated with Gram-positive Staphylococcus aureus and two Gram-negatives Escherichia coli DH5 alpha and Klebsiella oxytoca. For K. oxytoca, no differences were observed in comparison with a commercial stent (Biosoft(®) duo, Porges), although, for S. aureus all tested compositions had a higher inhibition of bacterial adhesion compared to the commercial stents. In case of E. coli, the addition of gelatin to the formulations reduced the bacterial adhesion in a highly significant manner compared to the commercial stents. The stents produced by the developed technology fulfill the requirements for ureteral stents and will contribute in the development of biocompatible and bioresorbable urinary stents.

  5. Acute Carotid Artery Stent Thrombosis Due to Dual Antiplatelet Resistance

    SciTech Connect

    Köklü, Erkan Arslan, Şakir; Yüksel, İsa Öner; Bayar, Nermin; Koç, Pınar

    2015-08-15

    Carotid artery stenting (CAS) is a revascularization modality that is an alternative to carotid endarterectomy. The efficacy of CAS in primary and secondary prevention from ischemic stroke has been demonstrated in various trials. Acute thrombosis of CAS is a rare complication that can lead to dramatic and catastrophic consequences. We discuss a case of acute CAS thrombosis in a patient who had previously undergone successful CAS. CAS was performed in a 73-year-old man who had had dysarthria lasting 2 weeks with 95 % stenosis in his left internal carotid artery. An acute cerebrovascular event resulting in right-sided hemiplegia developed 24 h after the procedure. Computed tomographic carotid angiography revealed complete occlusion of the stent with thrombus. The cause of stent thrombosis was thought to be antiaggregant resistance to both acetylsalicylic acid and clopidogrel. The most important cause of acute CAS thrombosis is inadequate or ineffective antiaggregant therapy. Evaluating patients who are candidates for CAS for acetylsalicylic acid and clopidogrel resistance may preclude this complication.

  6. Successful Percutaneous Transluminal Angioplasty and Stenting in Acute Mesenteric Ischemia

    SciTech Connect

    Gartenschlaeger, Soeren Bender, Siegfried; Maeurer, Juergen; Schroeder, Ralf J.

    2008-03-15

    Acute mesenteric ischemia (AMI) is a life-threatening emergency. The complications are high by the time of diagnosis in most cases and therefore only few data on primary percutaneous intervention with percutaneous transluminal angioplasty (PTA) and stenting in AMI are available. We present the case of an 84-year-old woman who presented to our emergency department complaining of an acute worsening of pre-existing abdominal periumbilical pain, nausea, vomiting, and diarrhea. She had previously undergone percutaneous transluminal embolectomy for an acute occlusion of the left common femoral artery. Due to suspicion of intestinal infarction, conventional angiography of the aorta and the superior mesenteric artery (SMA) was performed and confirmed a proximal occlusion of the SMA. Percutaneous SMA recanalization with balloon dilation and subsequent stent implantation was carried out successfully. The abdominal symptoms subsided after this procedure. In AMI that is diagnosed early, endovascular stenting should be considered as an alternative treatment to the surgical approach that avoids the need for surgical bowel resection.

  7. The 10-year Trend of Periprocedural Complication Following Carotid Artery Stenting; Single Center Experience

    SciTech Connect

    Hong, Jeong-Ho; Kang, Jihoon; Yeo, Min-Ju; Kim, Beom Joon; Jang, Min Uk; Bae, Hee-Joon; Kwon, O-Ki; Hwang, Gyo Jun; Oh, Chang Wan; Jung, Cheolkyu; Lee, Ji Sung; Han, Moon-Ku

    2015-04-15

    PurposeCarotid endarterectomy and stenting are used to treat carotid stenosis, with the volume of carotid artery procedures increasing over the past decade. We investigated the 10-year trend of periprocedural complications with an increasing procedure volume of carotid stenting at a single tertiary hospital.MethodsWe collected 416 consecutive cases (384 patients) of carotid artery stenting performed for either symptomatic (231 cases, 55.5 %) or asymptomatic (185 cases, 44.5 %) internal carotid artery stenosis at a single center. Periprocedural complication was defined as any stroke, myocardial infarction, or death. Procedure-related outcome included any dissection, hemodynamic event, or periprocedural complication.ResultsThe mean age was 68.8 years (82.8 % males; range of 20–89 years); 23.9 % were older than 75 years. Before the procedure, 99.3 and 56.0 % of patients received antiplatelet and lipid-lowering medication, respectively. The overall periprocedural complication rate was 3.6 % (1.6 and 5.2 % in the asymptomatic and symptomatic group, respectively). The composite outcome of any stroke or death was 3.4 %. Periprocedural complication and procedure-related outcome showed a decremental trend with increasing procedure volume, and this trend remained after adjusting for confounders.ConclusionsOur study suggests that carotid stenting at an experienced center might reduce the periprocedural complications. Our periprocedural complication rate of carotid artery stenting may be comparable to, or somewhat lower than, that reported in other clinical trials.

  8. Type-A acute aortic dissection: combined operation plus stent management.

    PubMed

    Roux, Daniel; Brouchet, Laurent; Concina, Philippe; Elghobary, Tamer; Glock, Yves; Fournial, Gérard

    2002-05-01

    When the port of entry of acute type-A aortic dissection is at the level of the horizontal portion of the aortic arch, the latter should be replaced by a prosthesis. To avoid performing this difficult procedure in an emergency situation, we place a stent in the aortic arch. Then we replace the ascending aorta by a prosthesis.

  9. Stenting of partial and total coronary occlusions in Trinidad and Tobago.

    PubMed

    Thomas, C N; Williams, D H; Hinds, A; Daniel, S; Ryan, F; Ramroop, C; Nath, C F; Crosby, D

    2001-03-01

    In order to evaluate the efficacy and safety of coronary stenting, we reviewed the first 32 consecutive patients (34 vessels) who underwent elective coronary stenting during the period August 1999 to August 2000 inclusive at the Digital Lab installed at the Eric Williams Medical Sciences Complex, Trinidad and Tobago. Aspirin, heparin and ticlopidine were used routinely. Abciximab was used in selected cases (38%). The mean age of patients was 55 +/- 10 years. Eighty-one per cent were male, 52% were hypertensive and 21% were diabetic. Sixty-five per cent had severe angina. Prior Coronary Artery Bypass Grafting (CABG) was performed in 3% and previous Percutaneous Transluminal Coronary Angioplasty (PTCA) in 3%. Multivessel disease was present in 43%. The mean left ventricular ejection fraction was 53 +/- 12%. The culprit lesion was located in either the native left anterior descending (LAD) coronary artery (53%), right coronary artery (RCA) (31%), circumflex artery 13% and saphenous vein graft (3%). The mean baseline diameter stenosis was 91 +/- 9% and this was reduced to 13 +/- 33% after stenting. Procedural success was 100% for 26 partially occluded vs 50% for 8 totally occluded vessels. For the total occlusions, procedural success was inversely related to the duration of the occlusion. There were no cases of death, acute vessel closure, Q-wave myocardial infarction, repeat PTCA or emergent Coronary Artery Bypass Graft (CABG) during and following the procedure. Distal embolization occurred in one patient. The mean duration of hospital stay was one day (for 30 outpatient cases). One patient had recurrence of symptoms with a negative stress test. No patient underwent repeat angiography during the first year of follow-up. Coronary stents were successfully implanted at a tertiary care facility in the Caribbean with low in-hospital morbidity and mortality. Stents markedly reduced the diameter stenosis of the coronary lesion during PTCA. The incidence of clinical

  10. Late Stent Thrombosis Associated with Heavy Exercise

    PubMed Central

    Simsek, Ziya; Arslan, Sakir; Gundogdu, Fuat

    2009-01-01

    Bare-metal stents are commonly used in the treatment of coronary artery disease. Stent thrombosis usually occurs within the first 48 hours after stent deployment. After a week, the incidence of thrombosis is low. Late stent thrombosis (after 30 days) is rarely seen; however, its clinical outcomes are severe 30-day mortality rates of 20% to 48% and myocardial infarction rates of 60% to 70%. Herein, we present the case and discuss the treatment of a patient who, after heavy exercise, experienced acute myocardial infarction due to late thrombosis in a bare-metal stent. A 54-year-old man presented with unstable angina pectoris. Coronary angiography revealed critical occlusion of the middle right coronary artery. A bare-metal stent was implanted, and he was discharged from the hospital on a medical regimen. Eleven months later, he presented with acute myocardial infarction, which had developed after heavy exercise. Coronary angiography revealed occlusion of the stent in the right coronary artery. After the occlusion was crossed with a guidewire, balloon angioplasty was applied, and Thrombosis-in-Myocardial-Infarction (TIMI)-3 flow was restored. The patient was asymptomatic during his 5-day hospitalization and was discharged on dual antiplatelet therapy. In addition to presenting this patient's case, we discuss mechanisms that may contribute to late stent thrombosis, implications of the condition, and preventive therapy. PMID:19436813

  11. Primary Stenting of Intracranial Atherosclerotic Stenoses

    SciTech Connect

    Straube, T. Stingele, Robert; Jansen, Olav

    2005-04-15

    Purpose: To determine the feasibility and safety of stenting intracranial atherosclerotic stenoses.Methods: In 12 patients the results of primary intracranial stenting were evaluated retrospectively. Patient ages ranged from 49 to 79 years (mean 64 years). Six patients presented with stenoses in the anterior circulation, and six had stenosis in the posterior circulation. One patient presented with extra- and intracranial tandem stenosis of the left internal carotid artery. Three patients presented with acute basilar thrombosis, caused by high-grade basilar stenoses.Results: Intracranial stenoses were successfully stented in 11 of 12 patients. In one patient the stent could not be advanced over the carotid siphon to reach the stenosis of the ophthalmic internal carotid artery. Follow-up digital subtraction angiographic studies were obtained in two patients who had presented with new neurologic signs or symptoms. In both cases the angiogram did not show any relevant stenotic endothelial hyperplasia. In one patient, after local thrombolysis the stenosis turned out to be so narrow that balloon angioplasty had to be performed before stent deployment. All three patients treated for stenosis-related basilar thrombosis died due to brainstem infarction that had ensued before the intervention.Conclusions: Prophylactic primary stenting of intracranial stenoses of the anterior or posterior cerebral circulation can be performed with a low complication rate; technical problems such as stent flexibility must still be solved. Local thrombolysis followed by stenting in stenosis-related thrombotic occlusion is technically possible.

  12. Microfabrication and nanotechnology in stent design.

    PubMed

    Martinez, Adam W; Chaikof, Elliot L

    2011-01-01

    Intravascular stents were first introduced in the 1980s as an adjunct to primary angioplasty for management of early complications, including arterial dissection, or treatment of an inadequate technical outcome due to early elastic recoil of the atherosclerotic lesion. Despite the beneficial effects of stenting, persistent high rates of restenosis motivated the design of drug-eluting stents for delivery of agents to limit the proliferative and other inflammatory responses within the vascular wall that contribute to the development of a restenotic lesion. These strategies have yielded a significant reduction in the incidence of restenosis, but challenges remain, including incomplete repair of the endothelium at the site of vascular wall injury that may be associated with a late risk of thrombosis. A failure of vessel wall healing has been attributed primarily to the use of polymeric stent coatings, but the effects of the eluted drug and other material properties or design features of the stent cannot be excluded. Improvements in stent microfabrication, as well as the introduction of alternative materials may help to address those limitations that inhibit stent performance. This review describes the application of novel microfabrication processes and the evolution of new nanotechnologies that hold significant promise in eliminating existing shortcomings of current stent platforms.

  13. Rescue coronary stenting in acute myocardial infarction

    NASA Astrophysics Data System (ADS)

    Barbieri, Enrico; Meneghetti, Paolo; Molinari, Gionata; Zardini, Piero

    1996-01-01

    Failed rescue coronary angioplasty is a high risk situation because of high mortality. Coronary stent has given us the chance of improving and maintaining the patency of the artery. We report our preliminary experience of rescue stenting after unsuccessful coronary angioplasty.

  14. Microfabrication and Nanotechnology in Stent Design

    PubMed Central

    Martinez, Adam W.; Chaikof, Elliot L.

    2012-01-01

    Intravascular stents were first introduced in the 1980s as an adjunct to primary angioplasty for management of early complications, including arterial dissection, or treatment of an inadequate technical outcome due to early elastic recoil of the atherosclerotic lesion. Despite the beneficial effects of stenting, persistent high rates of restenosis motivated the design of drug eluting stents for delivery of agents to limit the proliferative and other inflammatory responses within the vascular wall that contribute to the development of a restenotic lesion. These strategies have yielded a significant reduction in the incidence of restenosis, but challenges remain, including incomplete repair of the endothelium at the site of vascular wall injury that may be associated with a late risk of thrombosis. A failure of vessel wall healing has been attributed to primarily to the use of polymeric stent coatings, but the effects of the eluted drug and other material properties or design features of the stent cannot be excluded. Improvements in stent microfabrication, as well as the introduction of alternative materials may help to address those limitations that inhibit stent performance. This review describes the application of novel microfabrication processes and the evolution of new nanotechnologies that hold significant promise in eliminating existing shortcomings of current stent platforms. PMID:21462356

  15. Stent Fracture: How Frequently Is It Recognized?

    PubMed Central

    Mohsen, Mohammed Khalil; Alqahtani, Awad; Al suwaidi, Jassim

    2013-01-01

    In spite of there being several case reports, coronary stent fracture is not a well-recognized entity and incidence rates are likely to be underestimated. In this article, we review different aspects of stent fracture, including incidence, classification, predictors, outcome, diagnosis, and management. PMID:23983912

  16. Mesenchymal stem cell seeding promotes reendothelialization of the endovascular stent.

    PubMed

    Wu, Xue; Wang, Guixue; Tang, Chaojun; Zhang, Dechuan; Li, Zhenggong; Du, Dingyuan; Zhang, Zhengcai

    2011-09-01

    This study is designed to make a novel cell seeding stent and to evaluate reendothelialization and anti-restenosis after the stent implantation. In comparison with cell seeding stents utilized in previous studies, Mesenchymal stem cells (MSCs) have advantages on promoting of issue repair. Thus it was employed to improve the reendothelialization effects of endovascular stent in present work. MSCs were isolated by density gradient centrifugation and determined as CD29(+) CD44(+) CD34(-) cells by immunofluorescence and immunocytochemistry; gluten and polylysine coated stents were prepared by ultrasonic atomization spray, and MSCs seeded stents were made through rotation culture according to the optimized conditions that were determined in previous studies. The results from animal experiments, in which male New Zealand white rabbits were used, show that the reendothelialization of MSCs coated stents can be completed within one month; in comparison with 316L stainless steel stents (316L SS stents) and gluten and polylysine coated stents, the intimal hyperplasia and in-stent restenosis are significantly inhibited by MSCs coated stents. Endovascular stent seeded with MSCs promotes reendothelialization and inhibits the intimal hyperplasia and in-stent restenosis compared with the 316L SS stents and the gluten and polylysine coated stents.

  17. Clinical and angiographic outcome of elective stent implantation in small coronary vessels: an analysis of the BENESTENT trial.

    PubMed

    Keane, D; Azar, A J; de Jaegere, P; Rutsch, W; de Bruyne, B; Legrand, V; Kiemeneij, F; de Feyter, P; van de Heuvel, P; Ozaki, Y; Morel, M A; Serruys, P W

    1996-12-01

    We examined the influence of vessel size using an intention-to-treat approach in 259 patients who underwent stent implantation and in 257 patients who underwent balloon angioplasty alone in the BENESTENT trial. In the stented population, smaller vessel size was associated with a higher stent:vessel ratio, a greater relative gain and a greater subsequent loss index, and a higher risk of adverse cardiac events. In the balloon angioplasty population small vessel size conveyed an increased requirement for revascularization but did not increase the risk of procedural failure or myocardial infarction during follow-up. Logistic regression indicated that decreasing vessel size (as a continous variable) was associated with an increasing risk of a cardiac event for both the stent and balloon angioplasty populations.

  18. Use of endovascular stents in atherosclerotic renovascular stenosis: blood pressure and renal function changes in hypertensive patients.

    PubMed

    Tagle, Rodrigo; Acevedo, Monica; Xu, Meng; Pohl, Marc; Vidt, Donald

    2007-08-01

    Atherosclerotic renal artery stenosis may result in hypertension and ischemic nephropathy. Renal artery endovascular stenting has emerged as current therapy; however, the percentage of patients who benefit from this procedure is still not well established. The authors studied 116 hypertensive patients with atherosclerotic renovascular stenosis who underwent successful renal artery stenting for the first time. At 1 year, there was a significant overall decrease in blood pressure in the group after stenting; however, there was no change in renal function. Also, no significant change in the number of antihypertensive drugs was noted. Blood pressure improved in 55% of the patients, worsened in 14%, and remained unchanged in 31%. Renal function improved in 16% of the patients, worsened in 30%, and remained stable in 54%. In relation to blood pressure control, patients with resistant or difficult-to-control hypertension showed the most improvement in blood pressure control after stenting.

  19. Successful transfemoral aortic valve implantation through aortic stent graft after endovascular repair of abdominal aortic aneurysm.

    PubMed

    Kawashima, Hideyuki; Watanabe, Yusuke; Kozuma, Ken

    2017-04-01

    The patient was a 91-year-old woman presenting with severe aortic valve stenosis. Pre-procedural computed tomography scan revealed a 45-mm abdominal aortic aneurysm (AAA). Transfemoral transcatheter aortic valve implantation (TF-TAVI) was performed after endovascular aortic repair (EVAR) of the AAA. The 23-mm Edwards Sapien XT system passed through the aortic stent graft smoothly. This is the first case report showing that successful TF-TAVI can be performed through a prior abdominal aortic stent graft. TF-TAVI after EVAR of AAA is a feasible option for patients with extremely poor access.

  20. Recommendations for management of antiplatelet therapy in patients undergoing elective noncardiac surgery after coronary stent implantation.

    PubMed

    Huang, Pei-Hsiu; Croce, Kevin J; Bhatt, Deepak L; Resnic, Frederic S

    2012-12-01

    Patients commonly undergo noncardiac surgical procedures after implantation of a coronary stent. In the case where surgery cannot be deferred until completing the minimum duration of dual antiplatelet therapy, the Brigham and Women's Hospital Cardiac Catheterization Laboratory recommends using a glycoprotein IIb/IIIa bridging protocol to minimize the risk of perioperative ischemic events. We discuss our algorithm for managing antiplatelet agents, including the newer agents, prasugrel and ticagrelor, in patients undergoing noncardiac surgery after coronary stenting and present our glycoprotein IIb/IIIa bridging strategy along with a review of the relevant pharmacodynamic and clinical evidence.

  1. Transjugular Insertion of Biliary Stents (TIBS) in Two Patients with Malignant Obstruction, Ascites, and Coagulopathy

    SciTech Connect

    Amygdalos, Michael A.; Haskal, Ziv J.; Cope, Constantin; Kadish, Steven L.; Long, William B.

    1996-03-15

    Two patients with pancreatic malignancies presented with biliary obstruction which could not be treated from an endoscopic approach. Standard transhepatic biliary drainage was relatively contraindicated because of moderate ascites and coagulopathy related to underlying liver disease. In one patient, a transjugular, transvenous approach was used to deliver a Wallstent endoprosthesis across the distal common bile duct obstruction in a single step procedure. In the second case, a previously placed biliary Wallstent was revised with an additional stent from a similar approach. Transjugular biliary catheterization offers a valuable alternative approach for primary stent placement or revision in patients with contraindication to standard transhepatic drainage.

  2. Stent-Graft Treatment for Bleeding Superior Mesenteric Artery Pseudoaneurysm After Pancreaticoduodenectomy

    SciTech Connect

    Suzuki, Kojiro Mori, Yoshine; Komada, Tomohiro; Matsushima, Masaya; Ota, Toyohiro; Naganawa, Shinji

    2009-07-15

    We report two cases of intraperitoneal bleeding from superior mesenteric artery (SMA) pseudoaneurysm after pancreaticoduodenectomy for pancreatic head carcinoma. In both cases, a stent-graft was deployed on the main SMA to exclude pseudoaneurysm and to preserve blood flow to the bowel. Bleeding stopped after the procedure. One patient was able to be discharged but died from carcinoma recurrence 4 months later. The other patient died of sepsis and stent-graft infection 5 months later. These patients remained free of intraperitoneal rebleeding during the follow-up period.

  3. [The bioresorbable coronary stent: a revolution].

    PubMed

    Koegler, Flora; De Benedetti, Edoardo

    2013-04-10

    Coronary angioplasty has undergone several technological revolutions: starting with balloon angioplasty, then with bare metal stent and finally with drug eluting stent (DES), this technique is now mature. However, once we thought the problem of instent restenosis solved with DES, new concerns arise with late and very late stent thrombosis. Should we therefore proscribe DES? How long should be the duration of dual antiplatelet therapy? And how should we manage the patients who need a surgery and are at high risk of bleeding? Are bioresorbable stents the final solution with their initial mechanical properties, then with their drug eluting effect against intra-stent restenosis, and finally with their complete resorption which leaves the artery free of any foreign material?

  4. Clinical experience with ureteral metal stents

    PubMed Central

    Al Aown, Abdulrahman; Iason, Kyriazis; Panagiotis, Kallidonis; Liatsikos, Evangelos N.

    2010-01-01

    Ureteral metal stents (MSs) present a minimally invasive tool to preserve the drainage of renal pelvis whenever ureteral patency is at risk to be obstructed due to extrinsic or intrinsic etiologies. Clinical experience with these stents demonstrates that they impose a promising alternative treatment option in ureteral pathologies that are difficult to be treated via common polymeric stents. Current application of MSs in the treatment of both benign and malignant ureteral obstruction reveals quite promising results. Nevertheless, the ideal MS that would provide uncomplicated long-term effectiveness is still lucking and current MS usage is facing several adverse effects between which stent obstruction, encrustation, infection, migration, and patient discomfort. Ongoing attempts to create more inert stent with sophisticated novel designs are expected to improve current MS efficiency. MSs will play a major role in the future as a routine management of a variety of ureteral pathologies. PMID:21369375

  5. Twelve or 30 Months of Dual Antiplatelet Therapy After Drug-eluting Stents

    PubMed Central

    Mauri, Laura; Kereiakes, Dean J.; Yeh, Robert W.; Driscoll-Shempp, Priscilla; Cutlip, Donald E.; Steg, P. Gabriel; Normand, Sharon-Lise T.; Braunwald, Eugene; Wiviott, Stephen D.; Cohen, David J.; Holmes, David R.; Krucoff, Mitchell W.; Hermiller, James; Dauerman, Harold L.; Simon, Daniel I.; Kandzari, David E.; Garratt, Kirk N.; Lee, David P.; Pow, Thomas K.; Lee, Peter Ver; Rinaldi, Michael J.; Massaro, Joseph M.

    2015-01-01

    Background Dual antiplatelet therapy is recommended after coronary stenting to prevent thrombotic complications, yet the benefits and risks of treatment beyond 1 year are uncertain. Methods Subjects were enrolled after a drug-eluting coronary stent procedure. After 12 months of thienopyridine (clopidogrel bisulfate [Plavix] or prasugrel [Effient/Efient]) with aspirin, subjects were randomized to continued thienopyridine or placebo for another 18 months; all continued aspirin. The co-primary effectiveness end points were stent thrombosis and major adverse cardiovascular and cerebrovascular events (a composite of death, myocardial infarction, or stroke) at 12 to 30 months. The primary safety end point was moderate or severe bleeding. Results Subjects (N=9,961) were randomized to continued thienopyridine or placebo. Continued thienopyridine reduced stent thrombosis (0.4% vs. 1.4%, hazard ratio 0.29, 95% confidence interval [CI] 0.17-0.48, P<0.001) and major adverse cardiovascular and cerebrovascular events (4.3% vs. 5.9%, hazard ratio 0.71, 95% CI 0.59-0.85, P<0.001). Myocardial infarction was reduced (2.1% vs. 4.1%, hazard ratio 0.47, P<0.001). Rates of all-cause mortality in the continued thienopyridine and placebo groups were 2.0 and 1.5%, respectively (hazard ratio 1.36, 95% CI 1.00-1.85, P=0.052). Moderate or severe bleeding was increased with continued thienopyridine (2.5% vs. 1.6%, P=0.001). An elevated hazard for stent thrombosis and myocardial infarction was observed in both groups during the 3 months following thienopyridine discontinuation. Conclusion Dual antiplatelet therapy beyond one year after drug-eluting stent placement significantly reduced the risks of stent thrombosis and major adverse cardiovascular and cerebrovascular events compared with aspirin alone, but was associated with increased bleeding. PMID:25399658

  6. Portal vein stent placement with or without varix embolization of jejunal variceal bleeding after hepatopancreatobiliary surgery.

    PubMed

    Shim, Dong Jae; Shin, Ji Hoon; Ko, Gi-Young; Kim, Yook; Han, Kichang; Gwon, Dong-Il; Ko, Heung-Kyu

    2017-04-01

    Background Extrahepatic portal hypertension after surgery involving the duodenum or jejunum might result in massive ectopic variceal bleeding. Purpose To report the results of portal vein stent placement with the addition of variceal embolization. Material and Methods Between January 2000 and June 2015, portal vein stent placement was attempted in 477 patients. Of these, 22 patients (age, 63 ± 10 years) with jejunal variceal bleeding caused by portal vein obstruction after surgery were included in this study. Computed tomography (CT) findings before and after treatment and the rates of technical and clinical success, complications, and clinical outcomes were retrospectively evaluated. Results Stent placement was successful in 19 of 22 patients. Additional variceal embolization was performed in five cases. Clinical success, defined as the cessation of bleeding without recurrence within 1 month, was achieved in 18 of 19 patients with technical success. One patient developed recurrent bleeding 4 days after stent placement and was successfully treated with additional variceal embolization. There were no procedure-related complications. A regression of the jejunal varices was noted in 14 of 19 patients on follow-up CT scans. During the follow-up period (258 days; range, 7-1196 days), stent occlusion and recurrent bleeding occurred in six and four patients, respectively, of the 19 patients who achieved technical success. Statistical analyses revealed no significant differences regarding stent patency between benign and malignant strictures. Conclusion Percutaneous, transhepatic, portal vein stent placement with or without jejunal variceal embolization appears to be a safe and effective treatment for jejunal variceal bleeding after surgery.

  7. Vascular Gene Transfer from Metallic Stent Surfaces Using Adenoviral Vectors Tethered through Hydrolysable Cross-linkers

    PubMed Central

    Fishbein, Ilia; Forbes, Scott P.; Adamo, Richard F.; Chorny, Michael; Levy, Robert J.; Alferiev, Ivan S.

    2014-01-01

    In-stent restenosis presents a major complication of stent-based revascularization procedures widely used to re-establish blood flow through critically narrowed segments of coronary and peripheral arteries. Endovascular stents capable of tunable release of genes with anti-restenotic activity may present an alternative strategy to presently used drug-eluting stents. In order to attain clinical translation, gene-eluting stents must exhibit predictable kinetics of stent-immobilized gene vector release and site-specific transduction of vasculature, while avoiding an excessive inflammatory response typically associated with the polymer coatings used for physical entrapment of the vector. This paper describes a detailed methodology for coatless tethering of adenoviral gene vectors to stents based on a reversible binding of the adenoviral particles to polyallylamine bisphosphonate (PABT)-modified stainless steel surface via hydrolysable cross-linkers (HC). A family of bifunctional (amine- and thiol-reactive) HC with an average t1/2 of the in-chain ester hydrolysis ranging between 5 and 50 days were used to link the vector with the stent. The vector immobilization procedure is typically carried out within 9 hr and consists of several steps: 1) incubation of the metal samples in an aqueous solution of PABT (4 hr); 2) deprotection of thiol groups installed in PABT with tris(2-carboxyethyl) phosphine (20 min); 3) expansion of thiol reactive capacity of the metal surface by reacting the samples with polyethyleneimine derivatized with pyridyldithio (PDT) groups (2 hr); 4) conversion of PDT groups to thiols with dithiothreitol (10 min); 5) modification of adenoviruses with HC (1 hr); 6) purification of modified adenoviral particles by size-exclusion column chromatography (15 min) and 7) immobilization of thiol-reactive adenoviral particles on the thiolated steel surface (1 hr). This technique has wide potential applicability beyond stents, by facilitating surface engineering of

  8. Development of a static bioactive stent prototype and dynamic aneurysm-on-a-chip(TM) model for the treatment of aneurysms

    NASA Astrophysics Data System (ADS)

    Reece, Lisa M.

    Aneurysms are pockets of blood that collect outside blood vessel walls forming dilatations and leaving arterial walls very prone to rupture. Current treatments include: (1) clipping, and (2) coil embolization, including stent-assisted coiling. While these procedures can be effective, it would be advantageous to design a biologically active stent, modified with magnetic stent coatings, allowing cells to be manipulated to heal the arterial lining. Further, velocity, pressure, and wall shear stresses aid in the disease development of aneurysmal growth, but the shear force mechanisms effecting wound closure is elusive. Due to these factors, there is a definite need to cultivate a new stent device that will aid in healing an aneurysm in situ. To this end, a static bioactive stent device was synthesized. Additionally, to study aneurysm pathogenesis, a lab-on-a-chip device (a dynamic stent device) is the key to discovering the underlying mechanisms of these lesions. A first step to the reality of a true bioactive stent involves the study of cells that can be tested against the biomaterials that constitute the stent itself. The second step is to test particles/cells in a microfluidic environment. Therefore, biocompatability data was collected against PDMS, bacterial nanocellulose (BNC), and magnetic bacterial nanocellulose (MBNC). Preliminary static bioactive stents were synthesized whereby BNC was grown to cover standard nitinol stents. In an offshoot of the original research, a two-dimensional microfluidic model, the Aneurysm-on-a-ChipTM (AOC), was the logical answer to study particle flow within an aneurysm "sac" - this was the dynamic bioactive stent device. The AOC apparatus can track particles/cells when it is coupled to a particle image velocimetry software (PIV) package. The AOC fluid flow was visualized using standard microscopy techniques with commercial microparticles/cells. Movies were taken during fluid flow experiments and PIV was utilized to monitor.

  9. Call for standards in technical documentation of intracoronary stents.

    PubMed

    Lanzer, Peter; Gijsen, Frank J H; Topoleski, L D Timmie; Holzapfel, Gerhard A

    2010-01-01

    At present, the product information of intracoronary stents provided by the industry contains only limited technical data restricting judgments on the in vivo performance of individual products. Available experimental and clinical evidence suggests that interventional target sites display highly heterogeneous biomechanical behavior needed to be matched by specific stent and stent delivery system characteristics. To allow individualized stent-lesion matching, both, understanding of biomechanical properties of the atherosclerotic coronary artery lesions and expert knowledge of the intracoronary stent systems, are required. Here, the authors review some of the initial data on mechanical properties of coronary artery lesions potentially relevant to stenting and suggest standards for technical documentation of intracoronary stents.

  10. Upper Gastrointestinal Stent Insertion in Malignant and Benign Disorders

    PubMed Central

    Kang, Hyoun Woo

    2015-01-01

    Upper gastrointestinal (GI) stents are increasingly being used to manage upper GI obstructions. Initially developed for palliative treatment of esophageal cancer, upper GI stents now play an emerging role in benign strictures of the upper GI tract. Because recurrent obstruction and stent-related complications are common, new modifications of stents have been implemented. Self-expandable metal stents (SEMS) have replaced older plastic stents. In addition, newly designed SEMS have been developed to prevent complications. This review provides an overview of the various types, indications, methods, complications, and clinical outcomes of upper GI stents in a number of malignant and benign disorders dividing the esophagus and gastroduodenum. PMID:26064817

  11. Biliary stenting: indications, choice of stents and results: European Society of Gastrointestinal Endoscopy (ESGE) clinical guideline.

    PubMed

    Dumonceau, J-M; Tringali, A; Blero, D; Devière, J; Laugiers, R; Heresbach, D; Costamagna, G

    2012-03-01

    This article is part of a combined publication that expresses the current view of the European Society of Gastrointestinal Endoscopy about endoscopic biliary stenting. The present Clinical Guideline describes short-term and long-term results of biliary stenting depending on indications and stent models; it makes recommendations on when, how, and with which stent to perform biliary drainage in most common clinical settings, including in patients with a potentially resectable malignant biliary obstruction and in those who require palliative drainage of common bile duct or hilar strictures. Treatment of benign conditions (strictures related to chronic pancreatitis, liver transplantation, or cholecystectomy, and leaks and failed biliary stone extraction) and management of complications (including stent revision) are also discussed. A two-page executive summary of evidence statements and recommendations is provided. A separate Technology Review describes the models of biliary stents available and the stenting techniques, including advanced techniques such as insertion of multiple plastic stents, drainage of hilar strictures, retrieval of migrated stents and combined stenting in malignant biliary and duodenal obstructions.The target readership for the Clinical Guideline mostly includes digestive endoscopists, gastroenterologists, oncologists, radiologists, internists, and surgeons while the Technology Review should be most useful to endoscopists who perform biliary drainage.

  12. Hybrid stent device of flow-diverting effect and stent-assisted coil embolization formed by fractal structure.

    PubMed

    Kojima, Masahiro; Irie, Keiko; Masunaga, Kouhei; Sakai, Yasuhiko; Nakajima, Masahiro; Takeuchi, Masaru; Fukuda, Toshio; Arai, Fumihito; Negoro, Makoto

    2016-05-01

    This paper presents a novel hybrid medical stent device. This hybrid stent device formed by fractal mesh structures provides a flow-diverting effect and stent-assisted coil embolization. Flow-diverter stents decrease blood flow into an aneurysm to prevent its rupture. In general, the mesh size of a flow-diverter stent needs to be small enough to prevent blood flow into the aneurysm. Conventional flow-diverter stents are not available for stent-assisted coil embolization, which is an effective method for aneurysm occlusion, because the mesh size is too small to insert a micro-catheter for coil embolization. The proposed hybrid stent device is capable of stent-assisted coil embolization while simultaneously providing a flow-diverting effect. The fractal stent device is composed of mesh structures with fine and rough mesh areas. The rough mesh area can be used to insert a micro-catheter for stent-assisted coil embolization. Flow-diverting effects of two fractal stent designs were composed to three commercially available stent designs. Flow-diverting effects were analyzed using computational fluid dynamics (CFD) analysis and particle image velocimetry (PIV) experiment. Based on the CFD and PIV results, the fractal stent devices reduce the flow velocity inside an aneurism just as much as the commercially available flow-diverting stents while allowing stent-assisted coil embolization.

  13. Late Stent Expansion and Neointimal Proliferation of Oversized Nitinol Stents in Peripheral Arteries

    SciTech Connect

    Zhao, Hugh Q. Nikanorov, Alexander; Virmani, Renu; Jones, Russell; Pacheco, Erica; Schwartz, Lewis B.

    2009-07-15

    For peripheral endovascular intervention, self-expanding (SE) stents are commonly oversized in relation to target arteries to assure optimal wall apposition and prevent migration. However, the consequences of oversizing have not been well studied. The purpose of this study was to examine the effects of SE stent oversizing (OS) with respect to the kinetics of late stent expansion and the long-term histological effects of OS. Pairs of overlapped 8 x 28-mm Nitinol SE stents were implanted into the iliofemoral arteries of 14 Yucatan swine. Due to variations in target artery size, the stent-to-artery ratio ranged from 1.2:1 to 1.9:1. Lumen and stent diameters were assessed by quantitative angiography at the time of implantation. Following angiographic assessment at 6 months, stented arteries were perfusion-fixed, sectioned, and stained for histological analysis. Immediately following implantation, the stents were found to be expanded to a range of 4.7-7.1 mm, largely conforming to the diameter of the recipient target artery. The stents continued to expand over time, however, and all stents had enlarged to nearly their 8-mm nominal diameter by 6 months. The histological effects of OS were profound, with marked increases in injury and luminal area stenosis, including a statistically significant linear correlation between stent-to-artery ratio and area stenosis. In this experimental model of peripheral endovascular intervention, oversized Nitinol SE stents are constrained by their target artery diameter upon implantation but expand to their nominal diameter within 6 months. Severe OS (stent-to-artery ratio >1.4:1) results in a profound long-term histological response including exuberant neointimal proliferation and luminal stenosis.

  14. In-Stent Stenosis of Stent Assisted Endovascular Treatment on Intracranial Complex Aneurysms

    PubMed Central

    Yoon, Kyeong-Wook

    2010-01-01

    Objective To introduce the frequency and segment analysis of in-stent stenosis for intracranial stent assisted endovascular treatment on complex aneurysms. Methods A retrospective study was performed in 158 patients who had intracranial complex aneurysms and were treated by endovascular stent application with or without coil embolization. Of these, 102 patients were evaluated with catheter based angiography after 6, 12, and 18 months. Aneurysm location, using stent, time to stenosis, stenosis rate and narrowing segment were analyzed. Results Among follow-up cerebral angiography done in 102 patients, 8 patients (7.8%) were shown an in-stent stenosis. Two patients have unruptured aneurysm and six patients have ruptured one. Number of Neuroform stents were 7 cases (7.5%) and Enterprise stent in 1 case (11.1%). Six patients demonstrated in-stent stenosis at 6 months after stent application and remaining two patients were shown at 12 months, 18 months, respectively. Conclusion In-stent stenosis can be confronted after intracranial stent deployment. In our study, no patient showed symptomatic stenosis and there were no patients who required to further treatment except continuing antiplatets medication. In-stent stenosis has been known to be very few when they are placed into the non-pathologic parent artery during the complex aneurysm treatment, but the authors found that it was apt to happen on follow up angiography. Although the related symptom was not seen in our cases, the luminal narrowing at the stented area may result the untoward hemodynamic event in the specific condition. PMID:21430973

  15. Y-Shaped Bilateral Self-Expandable Metallic Stent Placement for Malignant Hilar Biliary Obstruction: Data from a Referral Center for Palliative Care

    PubMed Central

    Di Mitri, R.; Mocciaro, F.

    2014-01-01

    Background and Aim. Malignant hilar strictures are a clinical challenge because of the current therapeutic approach and the poor prognosis. In recent years, self-expandable metallic stents have proven more effective than plastic stents for palliation of malignant hilar strictures, with the bilateral stent-in-stent technique registering a high success rate. We report our experience with Y-shaped endoscopic self-expandable metallic stents placement for treatment of advanced malignant hilar strictures. Methods. From April 2009 to August 2012, we prospectively collected data on patients treated with Y-shaped SEMS placement for advanced malignant hilar carcinoma. Data on technical success, clinical success, and complications were collected. Results. Twenty patients (9 males) were treated (mean age 64.2 ± 15.3 years). The grade of malignant hilar strictures according to the Bismuth classification was II in 5 patients (25%), IIIa in 1 (5%), and IV in 14 (70%). The mean bilirubin level was 14.7 ± 4.9 mg/dL. Technical success was achieved in all patients, with a significant reduction in bilirubin levels (2.9 ± 1.7 mg/dL). One patient experienced cholangitis as early complication, while in 2 patients stent ingrowth was observed. No stents migration was recorded. There was no procedure-related mortality. At the end of the follow-up (7.1 ± 3.1 months), 13 of the 20 patients (65%) had died. Conclusions. Our experience confirms endoscopic bilateral self-expandable metallic stents placement with stent-in-stent technique (Y-shaped configuration) as a feasible, effective, and safe procedure for palliation of unresectable malignant hilar strictures. PMID:24790548

  16. [Endovascular treatment of the renal artery aneurysm with stent and coils].

    PubMed

    Juszkat, Robert; Zarzecka, Anna; Stanisić, Michał; Majewski, Wacław

    2012-01-01

    Aneurysms of the renal artery are very rare and its incidence is estimated at 0.01% of population. A 50-year-old male was admitted to the Department of General and Vascular Surgery due to incidentally diagnosed aneurysm of the left renal artery. Due to wide neck of the aneurysm, a two-step procedure was planned. First, an intracranial stent was implanted into the left renal artery. Second, after 3 months, platinum coils were deposed in the aneurysm sac through the stent struts. Aneurysmal sac was totally occluded. Periprocedural course was uneventful. The endovascular embolization with the use of stent and detachable coils is a safe method of treatment of wide-necked renal artery aneurysms with preserving parent vessel patency.

  17. [Migration of a stent implanted in the pulmonary artery of a patient with tetralogy of Fallot].

    PubMed

    Palomero Rodríguez, M A; Gabaldón Rivilla, M; Cabestrero Alonso, D; Gonzalez Cibrián, C; Abelleira Pardeiro, C; Centella Hernánez, T; Collado Gutierrez, R; Asuero de Lis, M S; Gómez González, R

    2014-05-01

    Tetralogy of Fallot is a congenital heart disease that accounts for 11-13% of the congenital cardiomyopathies. Stenosis and hyperplasia of the pulmonary arteries occur in a high proportion of them as this disease causes a native stenosis of the pulmonary branch, which can be surgically repaired with a stent. The use of balloon expandable intravascular stents is an alternative technique to further surgery in patients with congenital heart diseases. However, despite the gradual increase in their use, the limited number of procedures, combined with the wide anatomical variability and different characteristics of these patients, even in expert hands, stent implants are associated with a not inconsiderable incidence of complications. These are not always obvious and often require performing surgery in patients who have already had multiple interventions, thus increasing the complexity and the risk.

  18. MR safety and imaging of neuroform stents at 3T.

    PubMed

    Nehra, Arvind; Moran, Christopher J; Cross, Dewitte T; Derdeyn, Colin P

    2004-10-01

    The Neuroform stent is a self-expanding nitinol stent designed for use in wide-necked intracranial aneurysms. Heating and imaging artifacts were evaluated by using a porcine carotid artery aneurysm model in a 3T MR system. A suspended Neuroform stent was tested for deflection. No heating was measured, and no evidence of deflection of the stent was found. Imaging artifacts were minimal. MR imaging in patients with Neuroform stent-treated aneurysms is safe and feasible.

  19. Cephalic Arch Stenosis in Autogenous Haemodialysis Fistulas: Treatment With the Viabahn Stent-Graft

    SciTech Connect

    Shawyer, Andrew; Fotiadis, Nicos I.; Namagondlu, Girish; Iyer, Arun; Blunden, Mark Raftery, Martin Yaqoob, Magdi

    2013-02-15

    Cephalic arch stenosis (CAS) is an important and common cause of dysfunction in autogenous haemodialysis fistulas that requires multiple reinterventions and aggressive surveillance. We evaluated the safety and efficacy of the Viabahn stent-graft for the management of CAS. Between April 2005 and October 2011, 11 consecutive patients [four men and seven women (mean age 56.7 years)] with CAS and dysfunctional fistulas were treated with insertion of 11 Viabahn stent-grafts. Six stent-grafts were inserted due to residual stenosis after angioplasty and five for fistuloplasty-induced rupture. No patient was lost to follow-up. The technical and clinical success rate was 100 %. Primary access patency rates were 81.8 % [95 % confidence interval (CI) 0.482-0.977] at 6 months and 72.7 % (95 % CI 0.390-0.939) at 12 months. Secondary access patency rates were 90.9 % at 6 months (95 % CI 0.587-0.997). There were no procedure-related complications. Mean follow-up was 543.8 days (range 156-2,282). The use of the Viabahn stent-graft in the management of CAS is technically feasible and, in this small series, showed patency rates that compare favorably with historical data of angioplasty and bare stents.

  20. Computational Modeling to Predict Fatigue Behavior of NiTi Stents: What Do We Need?

    PubMed

    Dordoni, Elena; Petrini, Lorenza; Wu, Wei; Migliavacca, Francesco; Dubini, Gabriele; Pennati, Giancarlo

    2015-05-20

    NiTi (nickel-titanium) stents are nowadays commonly used for the percutaneous treatment of peripheral arterial disease. However, their effectiveness is still debated in the clinical field. In fact a peculiar cyclic biomechanical environment is created before and after stent implantation, with the risk of device fatigue failure. An accurate study of the device fatigue behavior is of primary importance to ensure a successful stenting procedure. Regulatory authorities recognize the possibility of performing computational analyses instead of experimental tests for the assessment of medical devices. However, confidence in numerical methods is only possible after verification and validation of the models used. For the case of NiTi stents, mechanical properties are strongly dependent on the device dimensions and the whole treatments undergone during manufacturing process. Hence, special attention should be paid to the accuracy of the description of the device geometry and the material properties implementation into the numerical code, as well as to the definition of the fatigue limit. In this paper, a path for setting up an effective numerical model for NiTi stent fatigue assessment is proposed and the results of its application in a specific case study are illustrated.

  1. Computational Modeling to Predict Fatigue Behavior of NiTi Stents: What Do We Need?

    PubMed Central

    Dordoni, Elena; Petrini, Lorenza; Wu, Wei; Migliavacca, Francesco; Dubini, Gabriele; Pennati, Giancarlo

    2015-01-01

    NiTi (nickel-titanium) stents are nowadays commonly used for the percutaneous treatment of peripheral arterial disease. However, their effectiveness is still debated in the clinical field. In fact a peculiar cyclic biomechanical environment is created before and after stent implantation, with the risk of device fatigue failure. An accurate study of the device fatigue behavior is of primary importance to ensure a successful stenting procedure. Regulatory authorities recognize the possibility of performing computational analyses instead of experimental tests for the assessment of medical devices. However, confidence in numerical methods is only possible after verification and validation of the models used. For the case of NiTi stents, mechanical properties are strongly dependent on the device dimensions and the whole treatments undergone during manufacturing process. Hence, special attention should be paid to the accuracy of the description of the device geometry and the material properties implementation into the numerical code, as well as to the definition of the fatigue limit. In this paper, a path for setting up an effective numerical model for NiTi stent fatigue assessment is proposed and the results of its application in a specific case study are illustrated. PMID:26011245

  2. Recanalization with stent-based mechanical thrombectomy in anterior circulation major ischemic stroke.

    PubMed

    Cohen, José E; Gomori, John M; Leker, Ronen R; Moscovici, Samuel; Ramirez-Denoriega, Fernando; Itshayek, Eyal

    2012-01-01

    We report the use of a self-expanding stent as a thrombectomy device in 17 patients (mean age 64.3 years) with major ischemic stroke secondary to large vessel occlusion. The patients had a mean National Institutes of Health Stroke Scale (NIHSS) score of >12, no cerebral hemorrhage or early infarction signs that affected more than 1/3 of the endangered territory, and an insufficient collateral supply. Within 8 hours of symptom onset, a stent (Solitaire; ev3, Irvine, CA, USA) was deployed across the occluded segment (endovascular bypass step). A repeat angiogram was performed to evaluate reconstituted flow. The guide-catheter balloon was inflated for proximal carotid occlusion. The partially deployed stent was slowly pulled back (mechanical thrombectomy step) under continuous aspiration. Complete recanalization (TIMI grade 3 flow) was achieved in fewer than 66 minutes after femoral access in all patients, with complete clot removal in a mean of two thrombectomy attempts. No stent was permanently implanted. Two patients developed asymptomatic hemorrhagic transformation (11.8%). Two patients presented post-recanalization parenchymal hemorrhage (11.8%); one suffered an intracerebral and intraventricular hemorrhage 12 hours after a successful and uneventful procedure and died 10 days later. The modified Rankin Scale scores were 0 to 2 in 15 patients (88.2%) and 3 in one patient (5.9%) at 1 month. In our preliminary experience, rapid stent-based mechanical thrombectomy has had unprecedented success.

  3. Endovascular repair of the aortic arch in pigs by improved double-branched stent grafts

    PubMed Central

    Lin, C; Wang, L; Lu, Q; Li, C

    2013-01-01

    Introduction This study aimed to evaluate the feasibility of total endovascular repair of the aortic arch in pigs using improved integrated double-branched stent grafts. Methods Improved self-expandable stent grafts with a main body and two integrated branches were prepared for the repair of the aortic arch in six pigs. The feasibility of using these stent grafts was evaluated with arteriography, computed tomography (CT), computed tomography angiography (CTA) and autopsy three months following the procedure. Results The double-branched stent grafts were placed successfully in the aortic arch in all six pigs. All pigs survived for at least three months and their biological behaviour was normal. Arteriography, CTA and animal necropsy revealed good fixation in all cases. Aortic valve function and coronary ostia remained intact, and CT of the head did not detect any lesion of cerebral infarction. Conclusions Endovascular repair of the aortic arch with an integrated double-branched stent graft is safe and feasible in animal studies. PMID:23484997

  4. iStent with Phacoemulsification versus Phacoemulsification Alone for Patients with Glaucoma and Cataract: A Meta-Analysis

    PubMed Central

    Malvankar-Mehta, Monali S.; Iordanous, Yiannis; Chen, Yufeng Nancy; Wang, Wan Wendy; Patel, Sangita Shantilal; Costella, John; Hutnik, Cindy M. L.

    2015-01-01

    Background Minimally invasive glaucoma surgeries (MIGS) have attracted significant attention, as they have been reported to lower intra-ocular pressure (IOP) and have an excellent safety profile. The iStent is an example of a minimally invasive glaucoma device that has received particular attention due to its early and wide spread utilization. There is a growing body of evidence supporting its use at the time of phacoemulsification to help lower IOP. However, it is still not clear how much of the IOP lowering effect can be attributed to the iStent, the crystalline lens extraction or both when inserted concurrently at the time of phacoemulsification. This has been an important issue in understanding its potential role in the glaucoma management paradigm. Purpose To conduct a systematic review and meta-analysis comparing the IOP lowering effect of iStent insertion at the time of phacoemulsification versus phacoemulsification alone for patients with glaucoma and cataracts. Methods A systematic review was conducted utilizing various databases. Studies examining the IOP lowering effect of iStent insertion in combination with phacoemulsification, as well as studies examining the IOP lowering effect of phacoemulsification alone were included. Thirty-seven studies, reporting on 2495 patients, met the inclusion criteria. The percentage reduction in IOP (IOPR%) and mean reduction in topical glaucoma medications after surgery were determined. The standardized mean difference (SMD) was computed as a measure of the treatment effect for continuous outcomes taking into account heterogeneity. Fixed-effect and random-effect models were applied. Results A 4% IOP reduction (IOPR%) from baseline occurred following phacoemulsification as a solo procedure compared to 9% following an iStent implant with phacoemulsification, and 27% following 2 iStents implants with phacoemulsification. Compared with cataract extraction alone, iStent with phacoemulsification resulted in significant

  5. Long-term Results of Endovascular Stent Graft Placement of Ureteroarterial Fistula

    SciTech Connect

    Okada, Takuya Yamaguchi, Masato; Muradi, Akhmadu Nomura, Yoshikatsu; Uotani, Kensuke; Idoguchi, Koji; Miyamoto, Naokazu Kawasaki, Ryota; Taniguchi, Takanori; Okita, Yutaka; Sugimoto, Koji

    2013-08-01

    PurposeTo evaluate the safety, efficacy, and long-term results of endovascular stent graft placement for ureteroarterial fistula (UAF).MethodsWe retrospectively analyzed stent graft placement for UAF performed at our institution from 2004 to 2012. Fistula location was assessed by contrast-enhanced computed tomography (CT) and angiography, and freedom from hematuria recurrence and mortality rates were estimated.ResultsStent graft placement for 11 UAFs was performed (4 men, mean age 72.8 {+-} 11.6 years). Some risk factors were present, including long-term ureteral stenting in 10 (91 %), pelvic surgery in 8 (73 %), and pelvic radiation in 5 (45 %). Contrast-enhanced CT and/or angiography revealed fistula or encasement of the artery in 6 cases (55 %). In the remaining 5 (45 %), angiography revealed no abnormality, and the suspected fistula site was at the crossing area between urinary tract and artery. All procedures were successful. However, one patient died of urosepsis 37 days after the procedure. At a mean follow-up of 548 (range 35-1,386) days, 4 patients (36 %) had recurrent hematuria, and two of them underwent additional treatment with secondary stent graft placement and surgical reconstruction. The hematuria recurrence-free rates at 1 and 2 years were 76.2 and 40.6 %, respectively. The freedom from UAF-related and overall mortality rates at 2 years were 85.7 and 54.9 %, respectively.ConclusionEndovascular stent graft placement for UAF is a safe and effective method to manage acute events. However, the hematuria recurrence rate remains high. A further study of long-term results in larger number of patients is necessary.

  6. Continuum damage model for bioresorbable magnesium alloy devices - Application to coronary stents.

    PubMed

    Gastaldi, D; Sassi, V; Petrini, L; Vedani, M; Trasatti, S; Migliavacca, F

    2011-04-01

    The main drawback of a conventional stenting procedure is the high risk of restenosis. The idea of a stent that "disappears" after having fulfilled its mission is very intriguing and fascinating, since it can be expected that the stent mass decreases in time to allow the gradual transmission of the mechanical load to the surrounding tissues owing to controlled dissolution by corrosion. Magnesium and its alloys are appealing materials for designing biodegradable stents. The objective of this work is to develop, in a finite element framework, a model of magnesium degradation that is able to predict the corrosion rate, thus providing a valuable tool for the design of bioresorbable stents. Continuum damage mechanics is suitable for modeling several damage mechanisms, including different types of corrosion. In this study, the damage is assumed to be the superposition of stress corrosion and uniform microgalvanic corrosion processes. The former describes the stress-mediated localization of the corrosion attack through a stress-dependent evolution law, while the latter affects the free surface of the material exposed to an aggressive environment. Comparisons with experimental tests show that the developed model can reproduce the behavior of different magnesium alloys subjected to static corrosion tests. The study shows that parameter identification for a correct calibration of the model response on the results of uniform and stress corrosion experimental tests is reachable. Moreover, three-dimensional stenting procedures accounting for interaction with the arterial vessel are simulated, and it is shown how the proposed modeling approach gives the possibility of accounting for the combined effects of an aggressive environment and mechanical loading.

  7. Stent Placement on Fresh Venous Thrombosis

    SciTech Connect

    Vorwerk, Dierk; Guenther, Rolf W.; Schuermann, Karl

    1997-09-15

    Purpose: To report on the efficacy of fixing fresh venous thrombus to the venous wall by stent placement. Methods: Seven patients underwent stenting to treat acute venous thrombosis. In two patients, the hemodialysis fistula was thrombosed with the thrombus extending into the brachial veins. In three patients, the hemodialysis fistula was patent but massive swelling of the ipsilateral arm was caused by proximal venous thrombosis. Two patients presented with iliac venous thrombosis within stented pelvic veins. Stent placement was preceded by other mechanical thrombectomy methods in all cases. Results: Attachment of thrombus to the venous wall was successful in all cases treated. Acute rethrombosis did not occur. Follow-up patency in dialysis patients was 7.2 {+-} 2.1 months. One patient had rethrombosis of the dialysis graft 3 months after primary treatment. Three patients developed restenosis within a mean period of 7.7 months. One shunt remained patent for 10 months with no event of reobstruction during follow-up. In both patients with iliac stent placement, the vein remained patent over a follow-up period of 8 and 12 months respectively. Conclusion: Stenting fresh venous thrombus can achieve immediate venous patency. It may be used as an alternative approach when all other percutaneous methods fail. Frequent restenosis within stented veins limits its use to very selected cases.

  8. Training for advanced endoscopic procedures.

    PubMed

    Feurer, Matthew E; Draganov, Peter V

    2016-06-01

    Advanced endoscopy has evolved from diagnostic ERCP to an ever-increasing array of therapeutic procedures including EUS with FNA, ablative therapies, deep enteroscopy, luminal stenting, endoscopic suturing and endoscopic mucosal resection among others. As these procedures have become increasingly more complex, the risk of potential complications has also risen. Training in advanced endoscopy involves more than obtaining a minimum number of therapeutic procedures. The means of assessing a trainee's competence level and ability to practice independently continues to be a matter of debate. The use of quality indicators to measure performance levels may be beneficial as more advanced techniques and procedures become available.

  9. Are Carotid Stent Fractures Clinically Significant?

    SciTech Connect

    Garcia-Toca, Manuel; Rodriguez, Heron E.; Naughton, Peter A.; Keeling, Aiofee; Phade, Sachin V.; Morasch, Mark D.; Kibbe, Melina R.; Eskandari, Mark K.

    2012-04-15

    Purpose: Late stent fatigue is a known complication after carotid artery stenting (CAS) for cervical carotid occlusive disease. The purpose of this study was to determine the prevalence and clinical significance of carotid stent fractures. Materials and Methods: A single-center retrospective review of 253 carotid bifurcation lesions treated with CAS and mechanical embolic protection from April 2001 to December 2009 was performed. Stent integrity was analyzed by two independent observers using multiplanar cervical plain radiographs with fractures classified into the following types: type I = single strut fracture; type II = multiple strut fractures; type III = transverse fracture; and type IV = transverse fracture with dislocation. Mean follow-up was 32 months. Results: Follow-up imaging was completed on 106 self-expanding nitinol stents (26 closed-cell and 80 open-cell stents). Eight fractures (7.5%) were detected (type I n = 1, type II n = 6, and type III n = 1). Seven fractures were found in open-cell stents (Precise n = 3, ViVEXX n = 2, and Acculink n = 2), and 1 fracture was found in a closed-cell stent (Xact n = 1) (p = 0.67). Only a previous history of external beam neck irradiation was associated with fractures (p = 0.048). No associated clinical sequelae were observed among the patients with fractures, and only 1 patient had an associated significant restenosis ({>=}80%) requiring reintervention. Conclusions: Late stent fatigue after CAS is an uncommon event and rarely clinically relevant. Although cell design does not appear to influence the occurrence of fractures, lesion characteristics may be associated risk factors.

  10. Targeting In-Stent-Stenosis with RGD- and CXCL1-Coated Mini-Stents in Mice

    PubMed Central

    Weinandy, Stefan; Schreiber, Fabian; Megens, Remco T. A.; Theelen, Wendy; Smeets, Ralf; Jockenhövel, Stefan; Gries, Thomas; Möller, Martin; Klee, Doris; Weber, Christian; Zernecke, Alma

    2016-01-01

    Atherosclerotic lesions that critically narrow the artery can necessitate an angioplasty and stent implantation. Long-term therapeutic effects, however, are limited by excessive arterial remodeling. We here employed a miniaturized nitinol-stent coated with star-shaped polyethylenglycole (star-PEG), and evaluated its bio-functionalization with RGD and CXCL1 for improving in-stent stenosis after implantation into carotid arteries of mice. Nitinol foils or stents (bare metal) were coated with star-PEG, and bio-functionalized with RGD, or RGD/CXCL1. Cell adhesion to star-PEG-coated nitinol foils was unaltered or reduced, whereas bio-functionalization with RGD but foremost RGD/CXCL1 increased adhesion of early angiogenic outgrowth cells (EOCs) and endothelial cells but not smooth muscle cells when compared with bare metal foils. Stimulation of cells with RGD/CXCL1 furthermore increased the proliferation of EOCs. In vivo, bio-functionalization with RGD/CXCL1 significantly reduced neointima formation and thrombus formation, and increased re-endothelialization in apoE-/- carotid arteries compared with bare-metal nitinol stents, star-PEG-coated stents, and stents bio-functionalized with RGD only. Bio-functionalization of star-PEG-coated nitinol-stents with RGD/CXCL1 reduced in-stent neointima formation. By supporting the adhesion and proliferation of endothelial progenitor cells, RGD/CXCL1 coating of stents may help to accelerate endothelial repair after stent implantation, and thus may harbor the potential to limit the complication of in-stent restenosis in clinical approaches. PMID:27192172

  11. Trajectory surgical guide stent for implant placement.

    PubMed

    Adrian, E D; Ivanhoe, J R; Krantz, W A

    1992-05-01

    This article describes a new implant placement surgical guide that gives both implant location and trajectory to the surgeon. Radiopaque markers are placed on diagnostic dentures and a lateral cephalometric radiograph is made that shows the osseous anatomy at the symphysis and the anterior tooth location. The ideal implant location and trajectory data are transferred to a surgical stent that programs the angle and location of the fixtures at time of surgery. The stent has the additional benefit of acting as an occlusion rim, a mouth prop, and tongue retractor. Use of this stent has resulted in consistently programming the placement of implant fixtures that are prosthodontically ideal.

  12. Endovascular Techniques in Limb Salvage: Stents

    PubMed Central

    El-Sayed, Hosam F.

    2013-01-01

    In patients with critical limb ischemia, the first-line approach for limb salvage has shifted over the past decade from bypass surgery to endovascular intervention. Stenting for the treatment of lower-extremity arterial occlusive disease is an important tool and continues to evolve, with new stent designs and technologies that have been developed to provide superior patency rates and limb salvage. In this article, we discuss the role of peripheral stenting in the treatment of patients with critical limb ischemia, including a review of the relevant current literature and the future directions of such interventions. PMID:23805339

  13. Delivery of stents to target lesions: techniques of intraoperative stent implantation and intraoperative angiograms.

    PubMed

    Ing, F F

    2005-01-01

    Mullins et al. [6] reported the first use of stent implantation to treat stenotic branch pulmonary arteries in 1988. In the early to mid-1990s, numerous reports confirmed its safety and efficacy, but there were limited stent and balloon designs and stent implantations were performed using relatively large delivery systems (10- to 12-Fr sheaths) [7, 8]. The general accepted patient size was limited to those weighing 12 kg or greater. Intraoperative stent implantation for branch pulmonary artery stenosis was reported in the early to mid-1990s [1-3, 5, 9]. Indications in these early reports included small patient size or difficult anatomy or patients who had additional cardiac lesions and needed surgery independent of the branch stenosis. The idea was to take advantage of the open-heart exposure provided in the operating room to permit direct access to the stenotic segment. Hence, all intraoperative stent implants were performed under direct visualization on bypass. There were no discussions on advantages over the routine percutaneous approach. Currently, with advances in stent and balloon technology as well as increased operator experience, many of those reported cases probably would have undergone cardiac catheterization for a percutaneous stent implant rather than open-heart surgery. The purpose of this report is to review the current indications, advantages, and disadvantages of intraoperative stent implantation as well as to discuss the techniques that are helpful to optimize intraoperative stent positioning. The role and advantages of intraoperative angiography will also be presented.

  14. Treatment of Post-Stent Gastroesophageal Reflux by Anti-Reflux Z-Stent

    SciTech Connect

    Davies, Roger Philip; Kew, Jacqueline; Byrne, Peter D.

    2000-11-15

    Severe symptoms of heartburn and retrosternal pain consistent with gastro-esophageal reflux (GER) developed in a patient following placement of a conventional self-expanding 16-24-mm-diameter x 12-cm-long esophageal stent across the gastroesophageal junction to treat an obstructing esophageal carcinoma. A second 18-mm-diameter x 10-cm-long esophageal stent with anti-reflux valve was deployed coaxially and reduced symptomatic GER immediately. Improvement was sustained at 4-month follow-up. An anti-reflux stent can be successfully used to treat significant symptomatic GER after conventional stenting.

  15. Coronary aneurysm and stent fracture following stenting of a myocardial bridge.

    PubMed

    Lu, Hao; Ge, Lei; Ge, Junbo

    2016-01-01

    Myocardial bridge is the most common congenital coronary anomaly. We represent an extremely rare case of stent fracture combination with coronary aneurysm following stenting of a myocardial bridge. This 60-years-old male patient underwent coronary angiography in the local hospital four years ago. Coronary angiography revealed a myocardial bridge in the distal left anterior descending coronary artery (LAD). A 3.0 mm × 29 mm sirolimus eluting stent was deployed in the distal LAD. Three years later, repeat coronary angiography showed a large coronary aneurysm in the mid segment of the stent. The patient subsequently underwent coronary artery bypass grafting with left internal mammary artery (LIMA) to the distal segment of the LAD. But six months later, another coronary angiography showed a stent fracture in mid portion of the stent associated with a large coronary aneurysm, and the LIMA graft was totally occluded. A possible mechanism of stent fracture was long-standing and cyclic mechanical stress on the stent by myocardium. These forces over a period of time may lead to metal fatigue and eventually fracture. Based on the observation of fracture and aneurysm in this study, we recommend that myocardial bridge should not be treated with intracoronary stenting. © 2015 Wiley Periodicals, Inc.

  16. PulmoStent: In Vitro to In Vivo Evaluation of a Tissue Engineered Endobronchial Stent.

    PubMed

    Thiebes, Anja Lena; Kelly, Nicola; Sweeney, Caoimhe A; McGrath, Donnacha J; Clauser, Johanna; Kurtenbach, Kathrin; Gesche, Valentine N; Chen, Weiluan; Kok, Robbert Jan; Steinseifer, Ulrich; Bruzzi, Mark; O'Brien, Barry J; McHugh, Peter E; Jockenhoevel, Stefan; Cornelissen, Christian G

    2017-04-01

    Currently, there is no optimal treatment available for end stage tumour patients with airway stenosis. The PulmoStent concept aims on overcoming current hurdles in airway stenting by combining a nitinol stent with a nutrient-permeable membrane, which prevents tumour ingrowth. Respiratory epithelial cells can be seeded onto the cover to restore mucociliary clearance. In this study, a novel hand-braided dog bone stent was developed, covered with a polycarbonate urethane nonwoven and mechanically tested. Design and manufacturing of stent and cover were improved in an iterative process according to predefined requirements for permeability and mechanical properties and finally tested in a proof of concept animal study in sheep for up to 24 weeks. In each animal two stents were implanted, one of which was cell-seeded by endoscopic spraying in situ. We demonstrated the suitability of this membrane for our concept by glucose transport testing and in vitro culture of respiratory epithelial cells. In the animal study, no migration occurred in any of the twelve stents. There was only mild granulation tissue formation and tissue reaction; no severe mucus plugging was observed. Thus, the PulmoStent concept might be a step forward for palliative treatment of airway stenosis with a biohybrid stent device.

  17. Stent overlapping and geometric curvature influence the structural integrity and surface characteristics of coronary nitinol stents.

    PubMed

    Kapnisis, Konstantinos K; Halwani, Dina O; Brott, Brigitta C; Anderson, Peter G; Lemons, Jack E; Anayiotos, Andreas S

    2013-04-01

    Preliminary studies have revealed that some stents undergo corrosion and fatigue-induced fracture in vivo, with significant release of metallic ions into surrounding tissues. A direct link between corrosion and in-stent restenosis has not been clearly established; nonetheless in vitro studies have shown that relatively high concentrations of heavy metal ions can stimulate both inflammatory and fibrotic reactions, which are the main steps in the process of restenosis. To isolate the mechanical effects from the local biochemical effects, accelerated biomechanical testing was performed on single and overlapping Nickel-Titanium (NiTi) stents subjected to various degrees of curvature. Post testing, stents were evaluated using Scanning Electron Microscopy (SEM) to identify the type of surface alterations. Fretting wear was observed in overlapping cases, in both straight and curved configurations. Stent strut fractures occurred in the presence of geometric curvature. Fretting wear and fatigue fractures observed on stents following mechanical simulation were similar to those from previously reported human stent explants. It has been shown that biomechanical factors such as arterial curvature combined with stent overlapping enhance the incidence and degree of wear and fatigue fracture when compared to single stents in a straight tube configuration.

  18. Manual Replacement of Double J Stent Without Fluoroscopy (Double j stent replacement).

    PubMed

    Kose, Osman; Gorgel, Sacit Nuri; Ozbir, Sait; Yenigurbuz, Sekan; Kara, Cengiz

    2015-02-01

    It is not always possible to replace a ureteric stent with a new one due to the fact that tumoral effect increases in ureter with time. We present our experience of manual replacement of double J stent without fluoroscopy. The data from 23 female patients who underwent double J stent replacement with a total of 110 times was retrospectively analyzed. The steps of technique are as follows: take out distal end of the double J stent through urethra to external urethral meatus cystoscopically, insert a 0.035-inch guide wire through double J stent to the renal pelvis or intra pelvicaliceal system, take out old double J stent over guide wire, slide new stent over guide wire and at external meatus level take out guide wire while gently sliding distal end of double J stent over guide wire into urethra. The mean age was 58.39 ± 9.21 years. Cervical, endometrial, and ovarian cancer were diagnosed in 16, 4, and 3 patients respectively. The mean follow-up and indwelling period were 13.8 ± 5.2, 3.8 ± 0.6 months, respectively. Increased pelvicaliceal dilatation, serum creatinine level, or renal parenchymal loss was not observed. Replacement of double J stents with this technique is easy and can be used successfully in distal ureteral obstructions.

  19. Paraffin processing of stented arteries using a postfixation dissolution of metallic and polymeric stents.

    PubMed

    Fishbein, Ilia; Welch, Tre; Guerrero, David T; Alferiev, Ivan S; Adamo, Richard F; Chorny, Michael; Gupte, Rohit K; Tang, Yanqing; Levy, Robert J

    Studying the morphology of the arterial response to endovascular stent implantation requires embedding the explanted stented artery in rigid materials such as poly(methyl methacrylate) to enable sectioning through both the in situ stent and the arterial wall, thus maintaining the proper anatomic relationships. This is a laborious, time-consuming process. Moreover, the technical quality of stained plastic sections is typically suboptimal and, in some cases, precludes immunohistochemical analysis. Here we describe a novel technique for dissolution of metallic and plastic stents that is compatible with subsequent embedding of "destented" arteries in paraffin, fine sectioning, major staining protocols, and immunohistochemistry.

  20. Treatment of Acute Aortic Type B Dissection with Stent-Grafts

    SciTech Connect

    Hausegger, K.A.; Tiesenhausen, K.; Schedlbauer, P.; Oberwalder, P.; Tauss, J.; Rigler, B.

    2001-09-15

    Purpose: To evaluate the feasibility of endoluminal stent-grafts in the treatment of acute type B aortic dissections.Methods: In five patients with acute aortic type B dissections, sealing of the primary intimal tear with an endoluminal stent-graft was attempted. Indication for treatment was aneurysm formation in two patients and persistent pain in three patients. One of the latter also had an unstable dissection flap compromising the ostium of the superior mesenteric artery. The distance from the intimal tear to the left subclavian artery was <0.5 cm in four patients, who had typical type B dissections. In one patient with an atypical dissection the distance from the primary tear to the left subclavian artery was 4 cm. This patient had no re-entry tear. Talent tube grafts (World Medical Manufacturing Cooperation, Sunrise, FL, USA) were used in all patients.Results: Stent-graft insertion with sealing of the primary tear was successful in all patients. The proximal covered portion of the stent-graft was placed across the left subclavian artery in four patients (1x transposition of the left subclavian artery). Left arm perfusion was preserved via a subclavian steal phenomenon in the patients in whom the stent-graft covered the orifice of the left subclavian artery. The only procedural complication we observed was an asymptomatic segmental renal infarction in one patient. In the thoracic aorta thrombosis of the false aortic lumen occurred in all patients. In one patient the false lumen of the abdominal aorta thrombosed after 4 weeks; in the other three patients the status of the abdominal aorta remained unchanged compared with the situation prior to stent-graft insertion. As a late complication formation of a secondary aneurysm of the thoracic aorta was observed at the distal end of the stent-graft 3 months after the primary intervention. This aneurysm was treated by coaxial insertion of an additional stent-graft without complications.Conclusion: Endoluminal treatment

  1. Physiologic Effect of Stent Therapy for Inferior Vena Cava Obstruction Due to Malignant Liver Tumor

    SciTech Connect

    Kishi, Kazushi Sonomura, Tetsuo; Fujimoto, Hisashi; Kimura, Masashi; Yamada, Katsuya; Sato, Morio; Juri, Masanobu

    2006-02-15

    Purpose. To understand systemic the influence of stent therapy for inferior vena cava (IVC) obstruction due to advanced liver tumor. Methods. Seven patients with symptomatic IVC obstruction due to advanced primary (n 4) or secondary (n = 3) liver tumor were subjected to stent therapy. Enrollment criteria included high IVC pressure over 15 mmHg and the presence of edema and ascites. Z-stents were deployed using coaxial sheath technique via femoral venous puncture. Physiologic and hematobiochemical parameters were analyzed. Results. All procedures were successful, and the stents remained patent until patient death. Promptly after stent placement, the IVC flow recovered, and the venous blood pressure in the IVC below the obstruction level showed a significant decrease from 20.8 {+-} 1.2 mmHg (mean {+-} SE) to 10.7 {+-} 0.7 mmHg (p < 0.01). Transient mild increase of right atrial pressure was observed in 1 patient. During the following week prominent diuresis was observed in all patients. Mean urine output volume in the 3 days before the stent therapy was 0.81 {+-} 0.09 l/day compared with 2.1 {+-} 0.2 l/day (p < 0.01) in the 3 days after. The edema and ascites decreased in all patients. The caval pressure change correlated well (r > 0.6) with the urine volume increase, and with the decreased volume of edema and ascites. The urine volume increase correlated well with the decrement of edema, but not with that of ascites. Improvements for various durations in the levels of blood urea nitrogen, serum creatinine, lactate dehydrogenase, fibrinogen, and platelet count were found (p < 0.05). These hematobiochemical changes were well correlated with each other and with the decrement of ascites. Two patients showed a low blood sodium level of 128.5 mEq/l after intensive natriuresis, and one of them died on day 21 with hepatic failure, which was interpreted as maladaptation aggravation. The mean survival time was 94.1 {+-} 34.1 days (mean {+-} SD), ranging from 21 to 140 days

  2. Effect of technical parameters on transjugular intrahepatic portosystemic shunts utilizing stent grafts

    PubMed Central

    Andring, Brice; Kalva, Sanjeeva P; Sutphin, Patrick; Srinivasa, Rajiv; Anene, Alvin; Burrell, Marc; Xi, Yin; Pillai, Anil K

    2015-01-01

    AIM: To assess the effect of technical parameters on outcomes of transjugular intrahepatic portosystemic shunt (TIPS) created using a stent graft. METHODS: The medical records of 68 patients who underwent TIPS placement with a stent graft from 2008 to 2014 were reviewed by two radiologists blinded to the patient outcomes. Digital Subtraction Angiographic images with a measuring catheter in two orthogonal planes was used to determine the TIPS stent-to-inferior vena cava distance (SIVCD), hepatic vein to parenchymal tract angle (HVTA), portal vein to parenchymal tract angle (PVTA), and the accessed portal vein. The length and diameter of the TIPS stent and the use of concurrent variceal embolization were recorded by review of the patient’s procedure note. Data on re-intervention within 30 d of TIPS placement, recurrence of symptoms, and survival were collected through the patient’s chart. Cox proportional regression analysis was performed to assess the effect of these technical parameters on primary patency of TIPS, time to recurrence of symptoms, and all-cause mortality. RESULTS: There was no significant association between the SIVCD and primary patency (P = 0.23), time to recurrence of symptoms (P = 0.83), or all-cause mortality (P = 0.18). The 3, 6, and 12-mo primary patency rates for a SIVCD ≥ 1.5 cm were 82.4%, 64.7%, and 50.3% compared to 89.3%, 83.8%, and 60.6% for a SIVCD of < 1.5 cm (P = 0.29). The median time to stenosis for a SIVCD of ≥ 1.5 cm was 19.1 mo vs 15.1 mo for a SIVCD of < 1.5 cm (P = 0.48). There was no significant association between the following factors and primary patency: HVTA (P = 0.99), PVTA (P = 0.65), accessed portal vein (P = 0.35), TIPS stent diameter (P = 0.93), TIPS stent length (P = 0.48), concurrent variceal embolization (P = 0.13) and reinterventions within 30 d (P = 0.24). Furthermore, there was no correlation between these technical parameters and time to recurrence of symptoms or all-cause mortality. Recurrence of

  3. Nickel-associated delayed multiple white matter lesions after stent-assisted coil embolization of intracranial unruptured aneurysm.

    PubMed

    Park, Hun Soo; Nakagawa, Ichiro; Yokoyama, Shohei; Wajima, Daisuke; Wada, Takeshi; Motoyama, Yasushi; Kichikawa, Kimihiko; Nakase, Hiroyuki

    2017-02-20

    Metal-induced encephalopathy after stent-assisted coil embolization is extremely rare. The present report describes two patients who presented with symptomatic intracranial parenchymal edematous lesions after stent-assisted coil embolization. A 64-year-old woman underwent stent-assisted coil embolization for a left internal carotid artery aneurysm; 21 days after the procedure she presented with right hand weakness and MRI revealed multifocal white matter lesions. Another woman aged 52 years underwent stent-assisted coil embolization for right vertebral artery aneurysm; 18 days after the procedure she presented with left-sided sensory disturbance and MRI demonstrated multiple white matter lesions. Treatment in both cases resulted in improvement of these lesions after steroid pulse therapy, and the patients had no associated morbidity 4 months after the procedures. Clinicians should monitor for neurologic symptoms and postoperative delayed radiologic parenchymal edematous changes associated with the metal allergic reaction after nitinol stent-assisted coil embolization.

  4. Nickel-associated delayed multiple white matter lesions after stent-assisted coil embolization of intracranial unruptured aneurysm.

    PubMed

    Park, Hun Soo; Nakagawa, Ichiro; Yokoyama, Shohei; Wajima, Daisuke; Wada, Takeshi; Motoyama, Yasushi; Kichikawa, Kimihiko; Nakase, Hiroyuki

    2017-02-24

    Metal-induced encephalopathy after stent-assisted coil embolization is extremely rare. The present report describes two patients who presented with symptomatic intracranial parenchymal edematous lesions after stent-assisted coil embolization. A 64-year-old woman underwent stent-assisted coil embolization for a left internal carotid artery aneurysm; 21 days after the procedure she presented with right hand weakness and MRI revealed multifocal white matter lesions. Another woman aged 52 years underwent stent-assisted coil embolization for right vertebral artery aneurysm; 18 days after the procedure she presented with left-sided sensory disturbance and MRI demonstrated multiple white matter lesions. Treatment in both cases resulted in improvement of these lesions after steroid pulse therapy, and the patients had no associated morbidity 4 months after the procedures. Clinicians should monitor for neurologic symptoms and postoperative delayed radiologic parenchymal edematous changes associated with the metal allergic reaction after nitinol stent-assisted coil embolization.

  5. Effect of Stent Implantation on the Deformations of the Superficial Femoral Artery and Popliteal Artery: In Vivo Three-Dimensional Deformational Analysis from Two-Dimensional Radiographs.

    PubMed

    Schumann, Steffen; Gökgöl, Can; Diehm, Nicolas; Büchler, Philippe; Zheng, Guoyan

    2017-01-01

    The objective of this work was to develop a system for three-dimensional (3D) reconstruction of the femoropopliteal artery from two angiographic views and to quantify the in vivo 3D deformations in 18 patients before balloon angioplasty and after primary stent implantation. The procedure had an insignificant effect on the bending behavior of the artery, as the average mean curvature change within the lesion remained constant before (0.04 cm(-1) ± 0.03) and after stent implantation (0.03 cm(-1) ± 0.04). A significant effect of stent implantation was measured in terms of a decrease in arterial shortening during leg flexion.

  6. Stent-based percutaneous coronary interventions in small coronary arteries.

    PubMed

    Roguin, Ariel; Grenadier, Ehud

    2006-01-01

    A third to half of all percutaneous coronary interventions involve small diameter vessels of less than 3 mm. Small vessel size is a predictor of restenosis after balloon angioplasty, as well as after stent placement. Stents deployed in small arteries, have a higher metal-to-artery ratio; this may increase the risk of sub-acute thrombosis or restenosis. Various studies have shown that stent design, stent coating, and stent strut thickness may determine event-free survival. Dedicated stents for small vessels with less amount of metal, appropriate expansion to the vessel size with correct radial force and cells morphology, and less prothrombotic properties, may further improve the results of stenting in this setting (thinner struts, fewer cells, or loops per circumference). This review provides an update on the current status, review the major trials and define the clinical utility of small vessel stenting, particularly in the era of drug-eluting stents.

  7. Mechanical design of an intracranial stent for treating cerebral aneurysms.

    PubMed

    Shobayashi, Yasuhiro; Tanoue, Tetsuya; Tateshima, Satoshi; Tanishita, Kazuo

    2010-11-01

    Endovascular treatment of cerebral aneurysms using stents has advanced markedly in recent years. Mechanically, a cerebrovascular stent must be very flexible longitudinally and have low radial stiffness. However, no study has examined the stress distribution and deformation of cerebrovascular stents using the finite element method (FEM) and experiments. Stents can have open- and closed-cell structures, and open-cell stents are used clinically in the cerebrovasculature because of their high flexibility. However, the open-cell structure confers a risk of in-stent stenosis due to protrusion of stent struts into the normal parent artery. Therefore, a flexible stent with a closed-cell structure is required. To design a clinically useful, highly flexible, closed-cell stent, one must examine the mechanical properties of the closed-cell structure. In this study, we investigated the relationship between mesh patterns and the mechanical properties of closed-cell stents. Several mesh patterns were designed and their characteristics were studied using numerical simulation. The results showed that the bending stiffness of a closed-cell stent depends on the geometric configuration of the stent cell. It decreases when the stent cell is stretched in the circumferential direction. Mechanical flexibility equal to an open-cell structure was obtained in a closed-cell structure by varying the geometric configuration of the stent cell.

  8. Stent Fracture and Reocclusion After Placement of a Single Self-Expanding Stent in the Common Iliac Artery and Endovascular Treatment

    SciTech Connect

    Higashiura, Wataru Sakaguchi, Shoji; Morimoto, Kengo; Kichikawa, Kimihiko

    2008-09-15

    We present a case of fracture of a single self-expanding stent placed in the common iliac artery (CIA). An 80-year-old woman underwent placement of a self-expanding stent for CIA occlusion. Stent fracture and reocclusion were detected after 18 months. Successful revascularization was achieved using a stent-in-stent maneuver. The possibility of stent fracture with reocclusion should be considered following treatment with a single self-expanding stent for CIA occlusion.

  9. Rationale and design of a multidisciplinary national real-world registry on carotid stenting: the Italian Registry for Carotid Stenting (RISC).

    PubMed

    Biasi, Giorgio M; Deleo, Gaetano; Froio, Alberto; Cremonesi, Alberto; Inglese, Luigi; Lavitrano, Marialuisa; Setacci, Carlo

    2006-04-01

    The Registro Italiano per lo Stenting Carotideo (RISC, Italian Registry for Carotid Stenting) has been organized by Italian specialists from different disciplines directly involved in the prevention of stroke due to carotid plaques through stenting of carotid lesions. The Registry has been endorsed by the national societies of 4 different specialties: vascular surgery, interventional cardiology, radiology, and neuroradiology. Each society contributed in the planning stage. The basis for the registry is to collect data on carotid stenting procedures performed by different specialists with different techniques in a "real-world" setting without the limitations of a randomized clinical trial. The Registry was funded to enroll at least 1200 patients over a minimum period of 36 months. The results will be analyzed using the intention-to-treat principle and are anticipated in late 2006. Primary endpoints of the registry are the 30-day combined death and stroke rate and the occurrence of restenosis and ipsilateral neurological deficit at 12 and 24 months. Considerable attention has been paid to the registry's quality control program to ensure scientific validation. An online database facilitates the collection of data with speed and accuracy.

  10. Severe symptomatic intracranial internal carotid artery stenosis treated with intracranial stenting: a single center study with 58 patients

    PubMed Central

    Wang, Zi-Liang; Gao, Bu-Lang; Li, Tian-Xiao; Cai, Dong-Yang; Zhu, Liang-Fu; Xue, Jiang-Yu; Bai, Wei-Xing; Li, Zhao-Shuo

    2016-01-01

    PURPOSE We aimed to investigate the safety and effectiveness of intracranial stenting in a population with severe (≥70%) symptomatic intracranial internal carotid artery (ICA) atherosclerotic stenosis. METHODS Fifty-eight patients with severe intracranial ICA atherosclerotic stenosis were prospectively enrolled. The baseline data, cerebral angiography, success rate, perioperative complications, clinical and imaging follow-up were prospectively analyzed. RESULTS All patients had successful intracranial stenting (100%), and the mean degree of stenosis was improved from 84.3%±7.5% to 23.5%±5.1% after the stent procedure. During the 30-day perioperative period, only one patient (1.7%) had ischemic stroke. Seven patients (12.1%) had headache and dysphoria. Thirty-six patients (62.1%) had clinical follow-up for 6–68 months after stenting. Five female patients (13.9%) had ipsilateral stroke including one death, but no disabling stroke, while three other patients (8.3%) had ipsilateral temporary ischemic attack (TIA). The recurrent stroke rate was higher in patients presenting with stroke (4/17, 23.5%) than in patients presenting with TIA (1/19, 5.3%), with no statistical significance (P = 0.33). Thirteen patients (22.4%) had imaging follow-up of 5–12 months following stenting, five of whom (38.5%) had in-stent restenosis. CONCLUSION Intracranial stenting for patients with intracranial ICA atherosclerotic stenosis has a low perioperative stroke rate and decent outcome on long-term follow-up, despite a relatively high in-stent restenosis rate. PMID:26809831

  11. Combined use of videoendoscopy and X-ray imaging for improved monitoring of stenting application

    NASA Astrophysics Data System (ADS)

    Cysewska-Sobusiak, A. R.; Sowier, A.; Skrzywanek, P.

    2005-09-01

    The subject of this paper concerns advanced techniques of procedures and imaging used in minimally invasive surgery and in non-operable cases of the alimentary tract tumor therapy. Examples of videoendoscopy and X-ray imaging used for the application of stents (prostheses) and catheters allowing for the performance of diagnostic and endo-therapeutic procedures are described. The possibility was indicated to elaborate a new method of proceeding in tumor therapy in the patients for whom the methods used so far were ineffective. In the paper examples of combined imaging the application of metallic stents and plastic catheters allowing for the performance of diagnostic and therapeutic procedures are presented. The cases shown refer to tumor located in the esophagus and in the bile and pancreatic ducts.

  12. Reappraisal of primary balloon angioplasty without stenting for patients with symptomatic middle cerebral artery stenosis.

    PubMed

    Okada, Hideo; Terada, Tomoaki; Tanaka, Yuko; Tomura, Nagatsuki; Kono, Kenichi; Yoshimura, Ryo; Shintani, Aki

    2015-01-01

    There is a controversy regarding the safety and efficacy of intracranial stenting. We describe our experience with primary balloon angioplasty without stenting for symptomatic middle cerebral artery (MCA) stenosis. All patients who underwent balloon angioplasty without stenting for MCA stenosis between 1996 and 2010 were retrospectively reviewed. We evaluated technical success rates, degrees of stenosis, and stroke or death within 30 days. Among patients who were followed-up for > 1 year we evaluated latest functional outcomes, stroke recurrence at 1 year, and restenosis. In total 45/47 patients (95.7%) were successfully treated. Average pre- and postprocedure stenosis rates were 79.9% and 39.5%, respectively. Three neurological complications occurred within 30 days: one thromboembolism during the procedure; one lacunar infarction; and one fatal intraparenchymal hemorrhage after the procedure. Stroke or death rate within 30 days was 6.4%. Thirty-three patients were available for follow-up analysis with a mean period of 51.5 months. The combined rate of stroke or death within 30 days and ipsilateral ischemic stroke of the followed-up patients within 1 year beyond 30 days was 9.4%. Restenosis was observed in 26.9% of patients and all remained asymptomatic. In our retrospective series, balloon angioplasty without stenting was a safe, effective modality for symptomatic MCA stenosis. For patients refractory to medical therapy, primary balloon angioplasty may offer a better supplemental treatment option.

  13. Reappraisal of Primary Balloon Angioplasty without Stenting for Patients with Symptomatic Middle Cerebral Artery Stenosis

    PubMed Central

    OKADA, Hideo; TERADA, Tomoaki; TANAKA, Yuko; TOMURA, Nagatsuki; KONO, Kenichi; YOSHIMURA, Ryo; SHINTANI, Aki

    2015-01-01

    There is a controversy regarding the safety and efficacy of intracranial stenting. We describe our experience with primary balloon angioplasty without stenting for symptomatic middle cerebral artery (MCA) stenosis. All patients who underwent balloon angioplasty without stenting for MCA stenosis between 1996 and 2010 were retrospectively reviewed. We evaluated technical success rates, degrees of stenosis, and stroke or death within 30 days. Among patients who were followed-up for > 1 year we evaluated latest functional outcomes, stroke recurrence at 1 year, and restenosis. In total 45/47 patients (95.7%) were successfully treated. Average pre- and postprocedure stenosis rates were 79.9% and 39.5%, respectively. Three neurological complications occurred within 30 days: one thromboembolism during the procedure; one lacunar infarction; and one fatal intraparenchymal hemorrhage after the procedure. Stroke or death rate within 30 days was 6.4%. Thirty-three patients were available for follow-up analysis with a mean period of 51.5 months. The combined rate of stroke or death within 30 days and ipsilateral ischemic stroke of the followed-up patients within 1 year beyond 30 days was 9.4%. Restenosis was observed in 26.9% of patients and all remained asymptomatic. In our retrospective series, balloon angioplasty without stenting was a safe, effective modality for symptomatic MCA stenosis. For patients refractory to medical therapy, primary balloon angioplasty may offer a better supplemental treatment option. PMID:25746307

  14. Percutaneous Treatment of Iliac Aneurysms and Pseudoaneurysms with Cragg Endopro System 1 Stent-Grafts

    SciTech Connect

    Gasparini, Daniele; Lovaria, Andrea; Saccheri, Silvia; Nicolini, Antonio; Favini, Giorgio; Inglese, Luigi; Giorgetti, Pier Luigi; Basadonna, Pier Tommaso

    1997-09-15

    Purpose: To evaluate the feasibility and short-term follow-up results of treating iliac aneurysms by the Cragg Endopro System 1 stent-graft. Methods: Nine lesions (two pseudoaneurysms and seven atherosclerotic aneurysms) were treated in eight patients by percutaneous implantation of a total of 10 stent-grafts. The procedure was followed by anticoagulation with heparin for 6 days, then antiplatelet therapy. Follow-up was by color Doppler ultrasound scan at 2 days and 3 months after the procedure for all patients, and by venous digital subtraction angiography and/or angio-CT up to 12 months later for four patients. Results: Initial clinical success rate was 100% and there were two minor complications. In one case the delivery system was faulty resulting in failure to deploy the stent-graft. An additional device had to be used. At 3-12 months all prostheses were patent but one patient (12.5%) had a minimal pergraft leak. Conclusion: Percutaneous stent-grafting with this device is a safe and efficacious treatment of iliac artery aneurysms.

  15. Nanoparticle Drug- and Gene-eluting Stents for the Prevention and Treatment of Coronary Restenosis

    PubMed Central

    Yin, Rui-Xing; Yang, De-Zhai; Wu, Jin-Zhen

    2014-01-01

    Percutaneous coronary intervention (PCI) has become the most common revascularization procedure for coronary artery disease. The use of stents has reduced the rate of restenosis by preventing elastic recoil and negative remodeling. However, in-stent restenosis remains one of the major drawbacks of this procedure. Drug-eluting stents (DESs) have proven to be effective in reducing the risk of late restenosis, but the use of currently marketed DESs presents safety concerns, including the non-specificity of therapeutics, incomplete endothelialization leading to late thrombosis, the need for long-term anti-platelet agents, and local hypersensitivity to polymer delivery matrices. In addition, the current DESs lack the capacity for adjustment of the drug dose and release kinetics appropriate to the disease status of the treated vessel. The development of efficacious therapeutic strategies to prevent and inhibit restenosis after PCI is critical for the treatment of coronary artery disease. The administration of drugs using biodegradable polymer nanoparticles as carriers has generated immense interest due to their excellent biocompatibility and ability to facilitate prolonged drug release. Despite the potential benefits of nanoparticles as smart drug delivery and diagnostic systems, much research is still required to evaluate potential toxicity issues related to the chemical properties of nanoparticle materials, as well as to their size and shape. This review describes the molecular mechanism of coronary restenosis, the use of DESs, and progress in nanoparticle drug- or gene-eluting stents for the prevention and treatment of coronary restenosis. PMID:24465275

  16. Angioplasty and stent placement - carotid artery - discharge

    MedlinePlus

    ... angioplasty and stenting - discharge; CAS - discharge; Endarterectomy - carotid artery - discharge; Angioplasty - carotid artery - discharge ... were done to open a narrowed or blocked artery that supplies blood to your brain. Your health ...

  17. Coronary angioscopy before and after stent deployment

    NASA Astrophysics Data System (ADS)

    Denardo, Scott J.; Schatz, Richard A.; Rocha-Singh, Krishna J.; Wong, S. Chiu; Morris, Nancy A.; Strumpf, Robert K.; Heuser, Richard R.; Teirstein, Paul

    1993-09-01

    Coronary angioscopy was used in an attempt to visualize the internal architecture of cardiac vessels before and after deployment of Palmaz-Schatz stents in 50 patients. The vessel was successfully visualized in 48 (96%) of these patients. In 24 patients, angioscopy was performed both after preliminary balloon angioplasty and then again after stent deployment. In all 24 patients the diameter of the lumen appeared larger after stent deployment as compared to after balloon angioplasty. In 16 of these 24 patients a dissection was documented by angioscopy after balloon angioplasty. The dissection was absent after stent deployment in all 16 patients. In seven patients, thrombus that was not apparent by angiography was visualized by angioscopy. Moreover, in four patients, thrombus that was suggested by angiography could not be confirmed by angioscopy.

  18. [Numerical modeling of shape memory alloy vascular stent's self-expandable progress and "optimized grid" of stent].

    PubMed

    Xu, Qiang; Liu, Yulan; Wang, Biao; He, Jin

    2008-10-01

    Vascular stent is an important medical appliance for angiocardiopathy. Its key deformation process is the expandable progress of stent in the vessel. The important deformation behaviour corresponds to two mechanics targets: deformation and stress. This paper is devoted to the research and development of vascular stent with proprietary intellectual property rights. The design of NiTinol self-expandable stent is optimized by means of finite element software. ANSYS is used to build the finite element simulation model of vascular stent; the molding material is NiTinol shape memory alloy. To cope with the factors that affect the structure of stent, the shape of grid and so on, the self-expanding process of Nitinol stent is simulated through computer. By making a comparison between two kinds of stents with similar grid structure, we present a new concept of "Optimized Grid" of stent.

  19. Extracranial carotid angioplasty and stenting. Initial results and short-term follow-up.

    PubMed Central

    Vozzi, C R; Rodriguez, A O; Paolantonio, D; Smith, J A; Wholey, M H

    1997-01-01

    Carotid percutaneous transluminal angioplasty, with or without stent implantation, is becoming another therapeutic option for carotid revascularization. To evaluate the feasibility and effectiveness of the technique, from October of 1995 to March of 1997, we performed 24 percutaneous transluminal angioplasty procedures in 22 patients with severe extracranial carotid artery stenosis. Three common carotid and 21 internal carotid arteries were treated, and 19 procedures included stent implantation using nonarticulated PALMAZ stents (P154 and P204). Twelve patients were asymptomatic and 10 patients were symptomatic; 2 of the symptomatic patients had complete obstruction of the internal carotid artery that was successfully recanalized. Technical and angiographic success was achieved in 23 of 24 procedures, with the carotid artery obstruction diminishing from 85.6% +/- 8.5% to 5.7% +/- 3.2% (P < 0.001). Average stenosis length was 12.5 +/- 3.1 mm, and mean time of carotid occlusion during balloon inflation was 11.5 +/- 2.5 seconds. Three patients experienced transitory seizures during the procedure prior to dilation, 1 patient had a minor stroke with complete recovery within 72 hours, and 1 patient had a major stroke and died 45 days after the procedure. Clinical follow-up was achieved in all patients (mean, 10.5 +/- 7.2 months) and angiographic follow-up in 16 patients (mean, 6.3 +/- 1.2 months). The results obtained in this initial experience provide adequate support to continue further evaluation of this new therapeutic strategy. Images PMID:9339503

  20. Stenting in Acute Lower Limb Arterial Occlusions

    SciTech Connect

    Raja, Jowad; Munneke, Graham; Morgan, Robert; Belli, Anna-Maria

    2008-07-15

    Management of critical limb ischemia of acute onset includes surgical embolectomy, bypass grafting, aspiration thrombectomy, thrombolysis, and mechanical thrombectomy followed by treatment of the underlying cause. We present our experience with the use of stents to treat acute embolic/thrombotic occlusions in one iliac and three femoropopliteal arteries. Although this is a small case series, excellent immediate and midterm results suggest that stenting of acute occlusions of the iliac, superficial femoral, and popliteal arteries is a safe and effective treatment option.

  1. Coronary stenting: A matter of revascularization

    PubMed Central

    Bonaventura, Aldo; Montecucco, Fabrizio; Liberale, Luca

    2017-01-01

    In the last few decades, the recommended treatment for coronary artery disease has been dramatically improved by percutaneous coronary intervention (PCI) and the use of balloon catheters, bare metal stents (BMSs), and drug-eluting stents (DESs). Catheter balloons were burdened by acute vessel occlusion or target-lesion re-stenosis. BMSs greatly reduced those problems holding up the vessel structure, but showed high rates of in-stent re-stenosis, which is characterized by neo-intimal hyperplasia and vessel remodeling leading to a re-narrowing of the vessel diameter. This challenge was overtaken by first-generation DESs, which reduced re-stenosis rates to nearly 5%, but demonstrated delayed arterial healing and risk for late in-stent thrombosis, with inflammatory cells playing a pivotal role. Finally, new-generation DESs, characterized by innovations in design, metal composition, surface polymers, and anti-proliferative drugs, finally reduced the risk for stent thrombosis and greatly improved revascularization outcomes. New advances include bioresorbable stents potentially changing the future of revascularization techniques as the concept bases upon the degradation of the stent scaffold to inert particles after its function expired, thus theoretically eliminating risks linked with both stent thrombosis and re-stenosis. Talking about DESs also dictates to consider dual antiplatelet therapy (DAPT), which is a fundamental moment in view of the good outcome duration, but also deals with bleeding complications. The better management of patients undergoing PCI should include the use of DESs and a DAPT finely tailored in consideration of the potentially developing bleeding risk in accordance with the indications from last updated guidelines.

  2. Biomimicry, vascular restenosis and coronary stents.

    PubMed

    Schwartz, R S; van der Giessen, W J; Holmes, D R

    1998-01-01

    Biomimicry is in its earliest stages and is being considered in the realm of tissue engineering. If arterial implants are to limit neointimal thickening, purely passive structures cannot succeed. Bioactivity must be present, either by pharmacologic intervention or by fabricating a 'living stent' that contains active cellular material. As tissue engineering evolves, useful solutions will emerge from applying this knowledge directly to vascular biologic problems resulting from angioplasty, stenting, and vascular prosthesis research.

  3. Association between RDW and stent thrombosis in patients with ST-elevation myocardial infarction undergoing primary percutaneous coronary intervention

    PubMed Central

    Tunçez, Abdullah; Çetin, Mehmet Serkan; Çetin, Elif Hande Özcan; Yılmaz, Samet; Korkmaz, Ahmet; Uçar, Fatih Mehmet

    2017-01-01

    Abstract Stent thrombosis is a rare but potentially fatal complication of percutaneous coronary interventions (PCIs). In recent years, the predictive and prognostic value of the red cell distribution width (RDW) as an indicator of inflammation has been shown in many cardiovascular diseases. Aim of this study was to examine the predictive value of RDW for stent thrombosis in patients who underwent successful stent implantation for ST-elevation myocardial infarction (STEMI). In this retrospective study, 146 patients who underwent successful PCI to native coronary artery due to STEMI previously and presented with acute coronary syndrome with stent thrombosis were included (stent thrombosis group). A total of 175 patients who had similar procedural characteristics (type, diameter, and length of stent) and not had stent thrombosis were consisted control group. Patients were divided into tertiles according to the admission RDW values (12.9 ± 0.4, 14.2 ± 0.4, and 16.3 ± 1.5, respectively). Stent thrombosis developed in 47 (40.9%) patients in the lowest tertile, 39 (37.9%) patients in mid tertile, and 60 (58.3%) patients in the highest tertile (P = 0.006). Female gender ratio was statistically significantly higher in the 3rd tertile (13 [11.3%], 8 [7.8%], 24 [23.3%], P = 0.003, respectively). RDW (OR: 1.397 [95% CI 1.177–1.657], P < 0.001) and platelet count (OR: 1.008 [95% CI 1.004–1.012], P < 0.001) remained independent predictors of stent thrombosis after multivariate logistic regression analysis. ROC curve analysis demonstrated that, admission RDW values higher than 13.9 can predict the development of stent thrombosis with a sensitivity of 57% and a specificity of 52% (The area under the ROC curve: 0.59 [95% CI 0.53–0.65] P = 0.007). High RDW values found to be independently associated with the development of stent thrombosis in patients with STEMI. PMID:28151892

  4. Wingspan Stent for High-Grade Symptomatic Vertebrobasilar Artery Atherosclerotic Stenosis

    SciTech Connect

    Li Jian Zhao Zhenwei Gao Guodong Deng Jianping; Yu Jia; Gao Li; Yuan Yang; Qv Youzhi

    2012-04-15

    Purpose: This study was designed to present the treatment outcomes with Wingspan stent angioplasty of high-grade intracranial vertebrobasilar artery (VBA) stenosis in symptomatic patients. Methods: Between 2007 and 2010, the records of 30 patients with 31 intracranial high-grade VBA stenoses (all{>=}70%) who underwent elective stenting due to the failure of medical therapy were retrospectively reviewed. Clinical evaluation was performed based on the modified Rankin scale and the National Institutes of Health Stroke Scale. Results: In all cases, the stent deployment was technically successful. The mean stenosis decreased significantly from 82.28 {+-} 8.02% (range, 72-99%) to 11.18 {+-} 7.28% (range, 0-25%) after stent-assisted angioplasty (P < 0.05). Periprocedure complications occurred in 3 (10%) of 30 patients; there were 2 cases of perforator strokes and 1 case of transient flow insufficiency with stent overlap. Clinical follow-up (mean, 17.81 {+-} 11.49 months; range, 5-40 months) was available for 27 patients, and angiographic follow-up (mean, 9.95 {+-} 5.74 months, range, 5-20 months) was available for 19 patients. Only one case demonstrated recurrent symptoms with restenosis ({>=}50%). There were no recurrent ischemic events and no cases of restenosis in the other patients. Conclusions: According to our data, the Wingspan stent for symptomatic intracranial VBA stenoses is a safe and efficacious treatment alternative in cases with recurrent symptoms despite medical therapy. However, the improvement of outcome requires the reduction in the rate of procedure-related complications and long-term outcomes still have to be demonstrated.

  5. Resolution of Pulsatile Tinnitus after Venous Sinus Stenting in Patients with Idiopathic Intracranial Hypertension

    PubMed Central

    Dinkin, Marc; Suurna, Maria; Hannsgen, Kelly; Bui, Xem

    2016-01-01

    Objective Evaluate the role of venous sinus stenting in the treatment of pulsatile tinnitus among patients with Idiopathic Intracranial Hypertension (IIH) and significant venous sinus stenosis. Subjects and Methods A written informed consent approved by the Weill Cornell institutional review board was signed and obtained from the study participants. Thirty-seven consecutive patients with IIH and venous sinus stenosis who were treated with venous sinus stenting between Jan.2012-Jan.2016 were prospectively evaluated. Patients without pulsatile tinnitus were excluded. Tinnitus severity was categorized based on “Tinnitus Handicap Inventory” (THI) at pre-stent, day-0, 1-month, 3-month, 6-month, 12-month, 18-month and 2-year follow-up. Demographics, body-mass index (BMI), pre and post VSS trans-stenotic pressure gradient were documented. Statistical analysis performed using Pearson’s correlation, Chi-square analysis and Fischer’s exact test. Results 29 patients with a mean age of 29.5±8.5 years M:F = 1:28. Median (mean) THI pre and post stenting were: 4 (3.7) and 1 (1) respectively. Median time of tinnitus resolution post VSS was 0-days. There was significant improvement of THI (Δ Mean: 2.7 THI [95% CI: 2.3–3.1 THI], p<0.001) and transverse-distal sigmoid sinus gradient (Δ Mean: -15.3 mm Hg [95% CI: 12.7–18 mm Hg], p<0.001) post-stenting. Mean follow-up duration of 26.4±9.8 months (3–44 months). VSS was feasible in 100% patients with no procedural complications. Three-patients (10%) had recurrent sinus stenosis and tinnitus at mean follow-up of 12 months (6–30 months). Conclusion Venous sinus stenting is an effective treatment for pulsatile tinnitus in patients with IIH and venous sinus stenosis. PMID:27768690

  6. Extracranial Carotid Artery Stenting in Surgically High-Risk Patients Using the Carotid Wallstent Endoprosthesis:Midterm Clinical and Ultrasound Follow-Up Results

    SciTech Connect

    Maleux, Geert Bernaerts, Pauwel; Thijs, Vincent; Daenens, Kim; Vaninbroukx, Johan; Fourneau, Inge; Nevelsteen, Andre

    2003-08-15

    The purpose of this study was to evaluate the feasibility, safety and midterm outcome of elective implantation of the Carotid Wallstent (registered) in patients considered to be at high surgical risk. In a prospective study, 54 carotid artery stenoses in 51 patients were stented over a 24-month period. Three patients underwent bilateral carotid artery stenting. Institutional inclusion criteria for invasive treatment of carotid occlusive disease (carotid endarterectomy or carotid artery stenting) are patients presenting with a 70% or more symptomatic stenosis and those with an 80% or more asymptomatic stenosis having a life-expectancy of more than 1 year. All patients treated by carotid artery stenting were considered at high risk for carotid endarterectomy because of a hostile neck (17 patients-31.5%) or because of severe comorbidities (37 patients-68.5%). No cerebral protection device was used. Of the 54 lesions, 33 (61.1%) were symptomatic and 21 (38.8%) were asymptomatic. Follow-up was performed by physical examination and by duplex ultrasonography at 1 month, 6 months, 1 year and 2 years after the procedure. All 54 lesions could be stented successfully without periprocedural stroke. Advert events during follow-up (mean 13.9 {+-} 5.7 months) were non-stroke-related death in 6 patients (11.1%), minor stroke in 4 stented hemispheres(7.4%), transient ipsilateral facial pain in 1 patient (1.8%),infection of the stented surgical patch in 1 patient (1.8%) and asymptomatic in stent restenosis in 4 patients (7.4%). The percutaneous implantation of the Carotid Wallstent (registered) , even without cerebral protection device, appears to be a safe procedure with acceptable clinical and ultrasonographic follow-up results in patients at high surgical risk. But some late adverse events such as ipsilateral recurrence of non-disabling (minor) stroke or in stent restenosis still remain real challenging problems.

  7. Research of Customized Aortic Stent Graft Manufacture

    NASA Astrophysics Data System (ADS)

    Zhang, Lei; Chen, Xin; Liu, Muhan

    2017-03-01

    Thoracic descending aorta diseases include aortic dissection and aortic aneurysm, of which the natural mortality rate is extremely high. At present, endovascular aneurysm repair (EVAR) has been widely used as an effective means for the treatment of descending aortic disease. Most of the existing coating stents are standard design, which are unable to meet the size or structure of different patients. As a result, failure of treatment would be caused by dimensional discrepancy between stent and vessels, which could lead to internal leakage or rupture of blood vessels. Therefore, based on rapid prototyping sacrificial core – coating forming (RPSC-CF), a customized aortic stent graft manufactured technique has been proposed in this study. The aortic stent graft consists of film and metallic stent, so polyether polyurethane (PU) and nickel-titanium (NiTi) shape memory alloy with good biocompatibility were chosen. To minimum film thickness without degrading performance, effect of different dip coating conditions on the thickness of film were studied. To make the NiTi alloy exhibit super-elasticity at body temperature (37°C), influence of different heat treatment conditions on austenite transformation temperature (Af) and mechanical properties were studied. The results show that the customized stent grafts could meet the demand of personalized therapy, and have good performance in blasting pressure and radial support force, laying the foundation for further animal experiment and clinical experiment.

  8. Recent Advances in Drug Eluting Stents

    PubMed Central

    Puranik, Amey S.; Dawson, Eileen R.; Peppas, Nicholas A.

    2013-01-01

    One of the most common medical interventions to reopen an occluded vessel is the implantation of a coronary stent. While this method of treatment is effective initially, restenosis, or the re-narrowing of the artery frequently occurs largely due to neointimal hyperplasia of smooth muscle cells. Drug eluting stents were developed in order to provide local, site-specific, controlled release of drugs that can inhibit neointima formation. By implementing a controlled release delivery system it may be possible to control the time release of the pharmacological factors and thus be able to bypass some of the critical events associated with stent hyperplasia and prevent the need for subsequent intervention. However, since the advent of first-generation drug eluting stents, long-term adverse effects have raised concerns regarding their safety. These limitations in safety and efficacy have triggered considerable research in developing biodegradable stents and more potent drug delivery systems. In this review, we shed light on the current state-of-the-art in drug eluting stents, problems related to them and highlight some of the ongoing research in this area. PMID:23117022

  9. A prospective evaluation of the safety and efficacy of the TAXUS Element paclitaxel-eluting coronary stent system for the treatment of de novo coronary artery lesions: Design and statistical methods of the PERSEUS clinical program

    PubMed Central

    2010-01-01

    Background Paclitaxel-eluting stents decrease angiographic and clinical restenosis following percutaneous coronary intervention compared to bare metal stents. TAXUS Element is a third-generation paclitaxel-eluting stent which incorporates a novel, thinner-strut, platinum-enriched metal alloy platform. The stent is intended to have enhanced radiopacity and improved deliverability compared to other paclitaxel-eluting stents. The safety and efficacy of the TAXUS Element stent are being evaluated in the pivotal PERSEUS clinical trials. Methods/Design The PERSEUS trials include two parallel studies of the TAXUS Element stent in single, de novo coronary atherosclerotic lesions. The PERSEUS Workhorse study is a prospective, randomized (3:1), single-blind, non-inferiority trial in subjects with lesion length ≤28 mm and vessel diameter ≥2.75 mm to ≤4.0 mm which compares TAXUS Element to the TAXUS Express2 paclitaxel-eluting stent system. The Workhorse study employs a novel Bayesian statistical approach that uses prior information to limit the number of study subjects exposed to the investigational device and thus provide a safer and more efficient analysis of the TAXUS Element stent. PERSEUS Small Vessel is a prospective, single-arm, superiority trial in subjects with lesion length ≤20 mm and vessel diameter ≥2.25 mm to <2.75 mm that compares TAXUS Element with a matched historical bare metal Express stent control. Discussion The TAXUS PERSEUS clinical trial program uses a novel statistical approach to evaluate whether design and metal alloy iterations in the TAXUS Element stent platform provide comparable safety and improved procedural performance compared to the previous generation Express stent. PERSEUS trial enrollment is complete and primary endpoint data are expected in 2010. PERSEUS Workhorse and Small Vessel are registered at http://www.clinicaltrials.gov, identification numbers NCT00484315 and NCT00489541. PMID:20059766

  10. Palliation of Obstructing Malignant Colonic Lesions Using Self-Expanding Metal Stents: A Single-Center Experience

    SciTech Connect

    Shrivastava, Vivek; Tariq, Omar; Tiam, ReeNee; Nyhsen, Christiane; Marsh, Ralph

    2008-09-15

    To evaluate the efficacy, risks, and survival after palliative colorectal stenting at a single center, we conducted a retrospective review of consecutive patients who had colorectal self-expanding metal stents (SEMSs) inserted over an 8-year period (September 1998 to September 2006) to relieve an obstructing colorectal tumor. All patients either had proven distant metastases or were unfit for surgical decompression. A single interventional radiologist (R.M.) inserted the stents, which were either Memotherm or WallFlex. Ninety-one patients with a median age of 73 years had a colorectal stent inserted for palliation of an obstructing colorectal malignancy. Technical success was achieved in 81 of 91 (89%) patients, and clinical success in 80 of 81 (99%). At the time of analysis (December 2006), 13 of 91 (14.2%) patients were alive. The patients who died had a median survival of 59 days, IQR 17-181 days. Seven (7/81) patients suffered stent migration, which occurred 10.3 days (IQR, 5-14 days) after the procedure. Three patients (3/81) re-presented with intestinal obstruction secondary to tumor ingrowth and 10 (10.9%) patients suffered bowel perforation. Ten patients (10.9%) had two stents inserted coaxially and overlapping in one procedure. This was performed in cases where the stricture was too long to be easily crossed by a single stent. We conclude that colorectal SEMS is a safe and effective mode of treatment for the palliation of obstructing colorectal cancers, which avoids high-risk surgery.

  11. Below-the-ankle Angioplasty and Stenting for Limb Salvage: Anatomical Considerations and Long-term Outcomes

    SciTech Connect

    Katsanos, Konstantinos Diamantopoulos, Athanasios; Spiliopoulos, Stavros; Karnabatidis, Dimitris; Siablis, Dimitris

    2013-08-01

    PurposeTo report the long-term angiographic and clinical results in a series of below-the-ankle (BTA) angioplasty procedures and to present some biomechanical issues related to the unique anatomical geometry of the ankle.MethodsWe performed a retrospective analysis of BTA angioplasty procedures. Clinical end points included technical success, patient mortality, salvage of the treated foot, and repeat target lesion revascularization. Imaging end points included primary patency, binary restenosis of the target lesion at the 50 % threshold, and stent integrity (stent fracture, deformation, or collapse). Univariate subgroup analysis was performed.ResultsIn total, 40 limbs in 37 patients (age 73.5 {+-} 8.2 years) with critical limb ischemia were included and 42 inframalleolar lesions (4.2 {+-} 1.4 cm) were analyzed. Technical success was achieved in 95.2 % (40 of 42). Provisional stent placement was performed in 45.2 % (19 of 42). Two patients died, and two major amputations occurred up to 3 years. At 1 year, overall primary vessel patency was 50.4 {+-} 9.1 %, lesion binary restenosis rate was 64.1 {+-} 8.3 %, and repeat intervention-free survival was 93.6 {+-} 4.3 % according to life table analysis of all treated lesions. Pairwise subgroup analysis showed that BTA self-expanding stents were associated with significantly higher restenosis and poorer primary patency compared to plain balloon angioplasty or sirolimus-eluting balloon-expandable stents. Significant deformation and/or fracture of balloon-expandable stents placed BTA were identified in five of 11. Dynamic imaging showed that the dorsalis pedis artery is kinked during foot dorsiflexion, whereas the distal posterior tibial artery is kinked during plantar flexion of the foot.ConclusionBTA angioplasty for critical limb ischemia treatment is safe and feasible with satisfactory long-term results. BTA stent placement must be reserved for bailout indications.

  12. Temporary duodenal stenting as a bridge to ERCP for inaccessible papilla due to duodenal obstruction: a retrospective study

    PubMed Central

    Donatelli, Gianfranco; Cereatti, Fabrizio; Dumont, Jean-Loup; Dhumane, Parag; Tuszynski, Thierry; Derhy, Serge; Meduri, Alexandre; Vergeau, Bertrand Marie; Meduri, Bruno

    2016-01-01

    Background and study aims: Duodenal obstruction may prevent performance of endoscopic retrograde cholangiopancreatography (ERCP). Percutaneous transhepatic biliary drainage (PTBD) or Endoscopic ultrasonograhy-guided biliary access (EUS-BD) are alternative treatments but are associated with a higher morbidity and mortality rate. The aim of the study is to report overall technical success rate and clinical outcome with deployment of temporary fully or partially covered self-expanding duodenal stent (pc/fcSEMS) as a bridge to ERCP in case of inaccessible papilla due to duodenal strictures. Patients and methods: This retrospective study included 66 consecutive patients presenting with a duodenal stricture impeding the ability to perform an ERCP. Provisional duodenal stenting was performed as a bridge to ERCP. A second endoscopic session was performed to remove the provisional stent and to perform an ERCP. Afterward, a permanent duodenal stent was delivered if necessary. Results: Sixty-six duodenal stents (17 pcSEMS and 49 fcSEMS) were delivered with a median indwelling time of 3.15 (1 – 7) days. Two migrations occurred in the pcSEMS group, 1 of which required lower endoscopy for retrieval. No other procedure-related complications were observed. At second endoscopy a successful ERCP was performed in 56 patients (85 %); 10 patients (15 %) with endoscopic failure underwent PTBD or EUS-BD. Forty patients needed permanent duodenal stenting. Conclusions: Provisional removable covered duodenal stenting as a bridge to ERCP for duodenal obstruction is safe procedure and in most cases allows successful performance of therapeutic ERCP. This technique could be a sound option as a step up approach before referring such cases for more complex techniques such as EUS-BD or PTBD. PMID:27652301

  13. Ulcerated Radiodermatitis Induced after Fluoroscopically Guided Stent Implantation Angioplasty

    PubMed Central

    Herz-Ruelas, Maira Elizabeth; Gómez-Flores, Minerva; Moxica-del Angel, Joaquín; Miranda-Maldonado, Ivett; Gutiérrez-Villarreal, Ilse Marilú; Villarreal-Rodríguez, Adriana Orelia

    2014-01-01

    Cases of radiation-induced skin injury after fluoroscopically guided procedures have been reported since 1996, though the majority of them have been published in Radiology and Cardiology literature, less frequently in Dermatology journals. Chronic radiation dermatitis induced by fluoroscopy can be difficult to diagnose; a high grade of suspicion is required. We report a case of an obese 46-year-old man with hypertension, dyslipidemia, and severe coronary artery disease. He developed a pruritic and painful atrophic ulcerated skin plaque over his left scapula, six months after fluoroscopically guided stent implantation angioplasty. The diagnosis of radiodermatitis was confirmed histologically. We report this case to emphasize the importance of recognizing fluoroscopy as a cause of radiation dermatitis. A good clinical follow-up at regular intervals is important after long and complicated procedures, since the most prevalent factor for injury is long exposure time. PMID:25276441

  14. DISCOVER: Dutch Iliac Stent trial: COVERed balloon-expandable versus uncovered balloon-expandable stents in the common iliac artery: study protocol for a randomized controlled trial

    PubMed Central

    2012-01-01

    revascularization of the common iliac artery, followed by placement of one or more uncovered balloon-expandable stents. The study group will undergo the same treatment, however one or more PTFE-covered balloon-expandable stents will be placed. When necessary, the aorta, external iliac artery, common femoral artery, superficial femoral artery and deep femoral artery will be treated, using the standard treatment. The primary endpoint is absence of binary restenosis rate. Secondary endpoints are reocclusion rate, target-lesion revascularization rate, clinical success, procedural success, hemodynamic success, major amputation rate, complication rate and mortality rate. Main study parameters are age, gender, relevant co-morbidity, and several patient, disease and procedure-related parameters. Trial registration Dutch Trial Register, NTR3381. PMID:23164097

  15. Computational Study of Axial Fatigue for Peripheral Nitinol Stents

    NASA Astrophysics Data System (ADS)

    Meoli, Alessio; Dordoni, Elena; Petrini, Lorenza; Migliavacca, Francesco; Dubini, Gabriele; Pennati, Giancarlo

    2014-07-01

    Despite their success as primary treatment for vascular diseases, Nitinol peripheral stents are still affected by complications related to fatigue failure. Hip and knee movements during daily activities produce large and cyclic deformations of the superficial femoral artery, that concomitant to the effects of pulsatile blood pressure, may cause fatigue failure in the stent. Fatigue failure typically occurs in cases of very extended lesions, which often require the use of two or more overlapping stents. In this study, finite element models were used to study the fatigue behavior of Nitinol stents when subjected to cyclic axial compression in different conditions. A specific commercial Nitinol stent was chosen for the analysis and subjected to cyclic axial compression typical of the femoral vascular region. Three different configurations were investigated: stent alone, stent deployed in a tube, and two overlapping stents deployed in a tube. Results confirm that stent oversizing has an influence in determining both the mean and amplitude strains induced in the stent and plays an important role in determining the fatigue response of Nitinol stents. In case of overlapping stents, numerical results suggest higher amplitude strains concentrate in the region close to the overlapping portion where the abrupt change in stiffness causes higher cyclic compression. These findings help to explain the high incidence of stent fractures observed in various clinical trials located close to the overlapping portion.

  16. Self-Expandable Nitinol Stent Placement in Homocysteinemic Porcine Aorta

    PubMed Central

    França, Luís Henrique Gil; Pereira, Adamastor Humberto; Perini, Sílvio César

    2008-01-01

    PURPOSE To compare aortic intimal thickening of normal and hyperhomocysteinemic pigs (induced with a methionine-rich diet) following placement of a self-expanding nitinol stent. METHODS Eighteen Macau pigs were used. They were older than eight weeks in age and had an average weight of 30 kg. Pigs were randomly divided into two groups. The first, Group C (control), was fed a regular diet, and the second group, Group M, was fed a methionine-rich diet for 30 days to induce hyperhomocysteinemia. The self-expandable nitinol stents were 25mm in length and 8 mm in diameter after expansion. Blood samples were collected to measure total cholesterol, triglycerides, HDL and homocysteine concentrations. All animals were subjected to angiography. Thirty days after the procedure, the animals were sacrificed, and the abdominal aorta was removed for histological and digital morphometry analysis. RESULTS Under microscopic evaluation, the intima was significantly thicker in Group C than in Group M. When groups were compared by digital morphometric analysis, intimal thickening of the vessel wall was higher in Group C than in Group M. There was no significant change in total cholesterol, triglycerides or HDL concentrations in either group. In group C the levels of plasma homocysteine ranged from 14,40 to 16,73μmol/l; in Group M, plasma homocysteine levels ranged from 17.47 to 59.80 μmol/l after 30 days of a methionine-rich diet. CONCLUSION Compared to normal pigs, less intimal hyperplasia was observed in the abdominal aortas of hyperhomocysteinemic pigs thirty days after the insertion of a self-expandable nitinol stent. PMID:18438578

  17. Stent

    MedlinePlus

    ... of coronary artery disease. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine . 25th ed. Philadelphia, PA: ... Atherosclerotic peripheral arterial disease. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine . 25th ed. Philadelphia, PA: ...

  18. Treatment of Secondary Stent-Graft Collapse After Endovascular Stent-Grafting for Iliac Artery Pseudoaneurysms

    SciTech Connect

    Clevert, D.-A. Stickel, M.; Steitz, H.-O.; Kopp, R.; Strautz, T.; Flach, P.; Johnson, T.; Jung, E.M.; Jauch, K.W.; Reiser, M.

    2007-02-15

    We report the case of a patient who developed an asymptomatic pseudoaneurysm in the left external iliac artery after transplant nephrectomy. The pseudoaneurysm most probably arose as a suture aneurysm from the external iliac artery after removal of the graft renal artery. Obviously we can not exclude the possibility it was a true aneurysm, although this seems much less likely. The pseudoaneurysm was detected during a routine CT scan and was treated interventionally with a stent-graft. One month later the asymptomatic patient underwent a vascular ultrasound examination including color Doppler, power Doppler, and B-flow as a routine control. An endoleak with collapse of the stent-graft was diagnosed. There was no evidence of stent infection. At a reintervention, the pseudoaneurysm was successfully treated using two uncovered Palmaz stents at the proximal and distal edge of the stent graft. Peri- and post-interventional ultrasound and CT angiography confirmed the exclusion of the aneurysm without an endoleak.

  19. Fully biodegradable coronary stents : progress to date.

    PubMed

    Ramcharitar, Steve; Serruys, Patrick W

    2008-01-01

    The limitations of currently available metallic drug-eluting stents have renewed interest in biodegradable stents (BDS). Apart from removing the (offending) foreign material that may potentiate a thrombotic event, BDS have the advantage of avoiding 'full metal jackets,' and thus can preclude subsequent coronary surgery. In addition, they do not interfere with the diagnostic evaluation of non-invasive imaging such as cardiac magnetic resonance and CT. There are now several BDS in development or in clinical trials that incorporate a variety of biodegradable polymer technologies. Two broad categories of materials are generally used: those made from organic biopolymers and those made from corrodible metals. However, to date, none of the materials/stents tested have been able to establish a perfect balance between biocompatibility, the kinetics of degradation needed to maintain mechanical strength to limit recoil, and inflammation. However, studies, such as the ABSORB trial with the everolimus eluting poly-L-lactide stent, which demonstrated comparable restenotic rates with bare metallic stents and a low incidence of major adverse cardiac events (MACE) at 12 months of 3.3%, with only one patient having a non-Q-wave myocardial infarction and no target lesion revascularization, suggest that there has been significant progress with respect to the earlier prototypes. The acute recoil observed could potentially be addressed with the polytyrosine REVA stent currently being evaluated in the RESORB trial, which incorporates a novel locking mechanism within its design. Alternative BDS designs include the combination of an antiproliferative drug with endothelial progenitor cell capturing antibodies to facilitate epithelialization and/or dual eluting having, in addition to the antiproliferative drug, polymeric salicyclic acid to limit inflammation. Compared with biodegradable polymers, there are fewer metals used in the manufacture of BDS. The only metal BDS in trials is the

  20. Percutaneous Endoluminal Stent and Stent-Graft Placement for the Treatment of Femoropopliteal Aneurysms: Early Experience

    SciTech Connect

    Mueller-Huelsbeck, Stefan; Link, Johann; Schwarzenberg, Helmut; Walluscheck, Knut P.; Heller, Martin

    1999-03-15

    Purpose: To determine the efficacy of percutaneous endoluminal stents and stent-grafts for the treatment of isolated femoropopliteal aneurysms. Methods: Seven men (age 51-69 years) with femoropopliteal occlusions (n= 6) related to aneurysms and a patent femoropopliteal aneurysm (n= 1) were treated percutaneously. In two patients uncovered Wallstents and in five patients polyester-covered nitinol stents were implanted. Assessment was performed with Doppler ultrasound and duplex ultrasonography 24 hr, 1, 3, 6, 12, and 24 months after the intervention. Additionally, intraarterial angiography was performed at 6 months. Results: Stent placement succeeded in all cases. No immediate adjunctive surgical treatment was necessary. Ankle-brachial index (ABI) improved from 0.29 {+-} 0.29 (SD) before to 0.78 {+-} 0.23 (SD) 24 hr after the intervention. One patient was lost to follow-up. Stent-graft occlusion occurred in four patients: after 2 days (n1), 1 month (n= 2), and 3 months (n= 1). One of the patients, whose stent occluded at 1 month, underwent successful recanalization with local fibrinolysis therapy. Three of the seven, all with three-vessel run-off, demonstrated patency of the stent, which was assessed by duplex ultrasonography at 29, 31, and 34 months. Breaking of the stent struts or significant stent migration was not observed. Conclusions: These results in a small number of patients warrant further investigation to evaluate the role of percutaneous stents in femoropopliteal aneurysms. Until further data of clinical studies are available, this method cannot be recommended, and it cannot replace surgical treatment.

  1. Extent and distribution of in-stent intimal hyperplasia and edge effect in a non-radiation stent population.

    PubMed

    Weissman, N J; Wilensky, R L; Tanguay, J F; Bartorelli, A L; Moses, J; Williams, D O; Bailey, S; Martin, J L; Canos, M R; Rudra, H; Popma, J J; Leon, M B; Kaplan, A V; Mintz, G S

    2001-08-01

    Intimal hyperplasia within the body of the stent is the primary mechanism for in-stent restenosis; however, stent edge restenosis has been described after brachytherapy. Our current understanding about the magnitude of in vivo intimal hyperplasia and edge restenosis is limited to data obtained primarily from select, symptomatic patients requiring repeat angiography. The purpose of this study was to determine the extent and distribution of intimal hyperplasia both within the stent and along the stent edge in relatively nonselect, asymptomatic patients scheduled for 6-month intravascular ultrasound (IVUS) as part of a multicenter trial: Heparin Infusion Prior to Stenting. Planar IVUS measurements 1 mm apart were obtained throughout the stent and over a length of 10 mm proximal and distal to the stent at index and follow-up. Of the 179 patients enrolled, 140 returned for repeat angiography and IVUS at 6.4 +/- 1.9 months and had IVUS images adequate for analysis. Patients had 1.2 +/- 0.6 Palmaz-Schatz stents per vessel. There was a wide individual variation of intimal hyperplasia distribution within the stent and no mean predilection for any location. At 6 months, intimal hyperplasia occupied 29.3 +/- 16.2% of the stent volume on average. Lumen loss within 2 mm of the stent edge was due primarily to intimal proliferation. Beyond 2 mm, negative remodeling contributed more to lumen loss. Gender, age, vessel location, index plaque burden, hypercholesterolemia, diabetes, and tobacco did not predict luminal narrowing at the stent edges, but diabetes, unstable angina at presentation, and lesion length were predictive of in-stent intimal hyperplasia. In a non-radiation stent population, 29% of the stent volume is filled with intimal hyperplasia at 6 months. Lumen loss at the stent edge is due primarily to intimal proliferation.

  2. Difference in security of stent jail between Palmaz-Schatz, NIR, and Multi-Link stents: the effect of balloon inflation through stent struts.

    PubMed

    Kinoshita, T; Kobayashi, Y; De Gregorio, J; Nameki, M; Kuroda, N; Yamamoto, Y; Miyazaki, A; Masuda, Y

    1999-10-01

    After placing a stent in the main vessel of a bifurcation lesion, it is often necessary to perform further balloon inflation or stent placement through the stent struts in order to treat a lesion of the secondary vessel or side branch. This balloon inflation with dilatation through the cells of the stent in the main vessel results in stent strut disfigurement. This disfigurement causes various degrees of stenosis within the main vessel secondary to stent strut deformity. The degree of strut deformity, and therefore stenosis, may vary significantly depending on stent design and structure. A model of a bifurcation lesion with an angle of 45 degrees was created from acrylic resin. The diameters of the main vessel and the secondary vessel were both 3.5 mm. Deployment of the Palmaz-Schatz stent (PS, n = 5), NIR stent (n = 5), or Multi-Link stent (n = 5) was performed in the main vessel with a 3.5-mm balloon catheter inflated to 6 atm. A second 3.5-mm balloon catheter was then inflated to 6 atm through the stent struts of the main vessel and into the ostium of the secondary vessel. The minimal lumen diameter (MLD) and cross-sectional area (CSA) at the ostium of the side branch and the stenosis within the main vessel were then measured, taking into account the stent deformity that occurred. Kissing balloon dilatation with two 3.5-mm balloon catheters was then performed and the stenosis secondary to stent deformity in the main vessel was remeasured. The MLD of the Multi-Link stent at the side-branch ostium was greater compared with those of the Palmaz-Schatz stent or the NIR stent (2.4 +/- 0.1, 1.6 +/- 0.1, 1.7 +/- 0.1 mm, P < 0.01) and CSA (4.9 +/- 0.5, 2.7 +/- 0.3, 2.5 +/- 0.3 mm(2), P < 0.01). Balloon inflation through the stent struts caused stent deformity that resulted in some degree of stenosis within the stent of the main vessel in all three stent types. Kissing balloon inflation reduced, but never eliminated, this stenosis. The percent stenosis in the main vessel

  3. Stent thrombosis in 2008: definition, predictors, prognosis and treatment.

    PubMed

    Lemesle, Gilles; Delhaye, Cédric; Bonello, Laurent; de Labriolle, Axel; Waksman, Ron; Pichard, Augusto

    2008-01-01

    Stent thrombosis remains a major pitfall of stent implantation in contemporary percutaneous coronary intervention, leading to high rates of death and nonfatal myocardial infarction (MI). Recently, the emergence of drug-eluting stents (DES) has raised concerns regarding the occurrence of late and very late stent thrombosis. Last year, a standardized definition of stent thrombosis was established to provide consistency in the reporting of this complication and to enable accurate and reliable data to be described for both types of stents: bare metal and drug eluting. Subsequent to the publication of this new definition, many updated data have been reported in the literature. On the other hand, antiplatelet therapy response variability is a recent concept and its real place in the pathogenesis of stent thrombosis is yet to be determined. In this article, we review the definition of and predictors for stent thrombosis focusing on DES use and variability in response to antiplatelet therapy, prognosis and treatment.

  4. A review on fracture prevention of stent in femoropopliteal artery

    NASA Astrophysics Data System (ADS)

    Atan, Bainun Akmal Mohd; Ismail, Al Emran; Taib, Ishkrizat; Lazim, Zulfaqih

    2017-01-01

    Heavily calcific lesions, total occlusions, tortuous blood vessels, variable lengths of arteries, various dynamic loads and deformations in the femoropopliteal (FP) arterial segment make stenosis treatments are complicated. The dynamic forces in FP artery including bending, torsion and radial compression may lead to stent fracture (SF) and eventually to in-stent restenosis (ISR). Stent design specifically geometrical configurations are a major factor need to be improved to optimize stent expansion and flexibility both bending and torsion during stent deployment into the diseased FP artery. Previous studies discovered the influence of various stent geometrical designs resulted different structural behaviour. Optimizing stent design can improve stent performances: flexibility and radial strength to prevent SF in FP arterial segment

  5. Management of iatrogenic ureteric injury with retrograde ureteric stenting: an analysis of factors affecting technical success and long-term outcome.

    PubMed

    Chung, Daniel; Briggs, James; Turney, Benjamin W; Tapping, Charles Ross

    2017-02-01

    Background Iatrogenic ureteral injuries arise as serious complication following obstetrics, gynecological, general, and urological surgery with incidence in the range of 0.5-10%. Retrograde placement of double-J ureteric stent is a possible treatment option if the injury is not recognized at the time of surgery. Purpose To assess technical success and long-term outcome associated with retrograde ureteric stent insertion for iatrogenic ureteric injury. Material and Methods Between 1999 and 2011, 26 patients with initially unrecognized iatrogenic ureteric injury underwent initial management with retrograde ureteric stenting. Full case-notes were available for review in 25 patients. Results The mean interval from injury to attempted stenting was 19.4 days. Successful retrograde ureteric stenting was achieved in 21/25 patients (81%). Retrograde stenting failed in four patients, and nephrostomy followed by alternative procedures were performed instead. At a median follow-up interval of 9.7 months, normal anatomy was demonstrated on 12/21 patients (57%) and a stricture was observed in 6/21 patients (28%) with three requiring surgical intervention. Conclusion Retrograde stenting is a safe and efficient initial management in patients with iatrogenic ureteric injuries.

  6. British Society of Interventional Radiology Iliac Artery Angioplasty-Stent Registry III

    SciTech Connect

    Uberoi, Raman Milburn, Simon; Moss, Jon

    2009-09-15

    The objective of this study was to audit current practice in iliac artery intervention in the United Kingdom. In 2001 the British Society of Interventional Radiology Iliac Artery Angioplasty-Stent (BIAS) III registry provided the first national database for iliac intervention. It recommended that data collection needed to continue in order to facilitate the dissemination of comparative data to individual units. BIAS III was designed to continue this work and has a simplified data set with an online submission form. Interventionalists were invited to complete a 3-page tick sheet for all iliac angioplasties and stents. Questions covered risk factors, procedural data, and outcome. Data for 2233 patients were submitted from 37 institutions over a 43-month period. Consultants performed 80% of the procedures, 62% of which were for claudication. Fifty-four percent of lesions were treated with stents and 25% of patients underwent bilateral intervention, resulting in a residual stenosis of <50% in 98%. Ninety-seven percent of procedures had no limb complication and there was a 98% inpatient survival rate. In conclusion, these figures provide an essential benchmark for both audit and patient information. National databases need to be expanded across the range of interventional procedures, and their collection made simple and, preferably, online.

  7. Inadvertent Detachment of a Retrievable Intracranial Stent: Review of Manufacturer and User Facility Device Experience.

    PubMed

    Yub Lee, Sang; Won Youn, Sung; Kyun Kim, Ho; Rok Do, Young

    2015-04-01

    Few systematic surveys have dealt with the potential procedural risks associated with the use of retrievable intracranial stents [Solitaire Flow Restoration (Solitaire FR)], which have become effective tools for recanalizing acutely occluded cerebral arteries. The aim of this study was to present the real-world experiences of Solitaire-FR-related adverse events by reviewing the MAUDE (Manufacturer and User Facility Device Experience) as published on the United States Food and Drug Administration website. In total, 85 adverse events related to the use of the Solitaire FR stent were reported between March 2012 and October 2014. In 80 patients these adverse events were attributable to inadvertent detachment of the device. Thirteen of these 80 patients (16%) died after the procedure. Morbidity data were available in 62 patients, among whom 11 (18%) had suffered a procedure-related injury. Detachment occurred at the first, second, and third pass in nine (21%), 21 (49%), and 13 (30%) of the 43 patients for whom this information was available, respectively. Resistance was perceived by the physician during retrieval of the device in 12 patients, and lesion characteristics were noted in 13. A rescue maneuver was reported in 20 (25%) of the 80 patients in whom the adverse event was attributable to detachment of the device, resulting in flow reestablishment in 13 (65%). The risk of inadvertent detachment during stent retrieval cannot be overemphasized in real-world scenarios, and careful consideration of the "dos and don'ts" is essential for the achievement of a safe procedure.

  8. First Magnetic Resonance Imaging-Guided Aortic Stenting and Cava Filter Placement Using a Polyetheretherketone-Based Magnetic Resonance Imaging-Compatible Guidewire in Swine: Proof of Concept

    SciTech Connect

    Kos, Sebastian; Huegli, Rolf; Hofmann, Eugen; Quick, Harald H.; Kuehl, Hilmar; Aker, Stephanie; Kaiser, Gernot M.; Borm, Paul J. A.; Jacob, Augustinus L.; Bilecen, Deniz

    2009-05-15

    The purpose of this study was to demonstrate feasibility of percutaneous transluminal aortic stenting and cava filter placement under magnetic resonance imaging (MRI) guidance exclusively using a polyetheretherketone (PEEK)-based MRI-compatible guidewire. Percutaneous transluminal aortic stenting and cava filter placement were performed in 3 domestic swine. Procedures were performed under MRI-guidance in an open-bore 1.5-T scanner. The applied 0.035-inch guidewire has a PEEK core reinforced by fibres, floppy tip, hydrophilic coating, and paramagnetic markings for passive visualization. Through an 11F sheath, the guidewire was advanced into the abdominal (swine 1) or thoracic aorta (swine 2), and the stents were deployed. The guidewire was advanced into the inferior vena cava (swine 3), and the cava filter was deployed. Postmortem autopsy was performed. Procedural success, guidewire visibility, pushability, and stent support were qualitatively assessed by consensus. Procedure times were documented. Guidewire guidance into the abdominal and thoracic aortas and the inferior vena cava was successful. Stent deployments were successful in the abdominal (swine 1) and thoracic (swine 2) segments of the descending aorta. Cava filter positioning and deployment was successful. Autopsy documented good stent and filter positioning. Guidewire visibility through applied markers was rated acceptable for aortic stenting and good for venous filter placement. Steerability, pushability, and device support were good. The PEEK-based guidewire allows either percutaneous MRI-guided aortic stenting in the thoracic and abdominal segments of the descending aorta and filter placement in the inferior vena cava with acceptable to good device visibility and offers good steerability, pushability, and device support.

  9. First magnetic resonance imaging-guided aortic stenting and cava filter placement using a polyetheretherketone-based magnetic resonance imaging-compatible guidewire in swine: proof of concept.

    PubMed

    Kos, Sebastian; Huegli, Rolf; Hofmann, Eugen; Quick, Harald H; Kuehl, Hilmar; Aker, Stephanie; Kaiser, Gernot M; Borm, Paul J A; Jacob, Augustinus L; Bilecen, Deniz

    2009-05-01

    The purpose of this study was to demonstrate feasibility of percutaneous transluminal aortic stenting and cava filter placement under magnetic resonance imaging (MRI) guidance exclusively using a polyetheretherketone (PEEK)-based MRI-compatible guidewire. Percutaneous transluminal aortic stenting and cava filter placement were performed in 3 domestic swine. Procedures were performed under MRI-guidance in an open-bore 1.5-T scanner. The applied 0.035-inch guidewire has a PEEK core reinforced by fibres, floppy tip, hydrophilic coating, and paramagnetic markings for passive visualization. Through an 11F sheath, the guidewire was advanced into the abdominal (swine 1) or thoracic aorta (swine 2), and the stents were deployed. The guidewire was advanced into the inferior vena cava (swine 3), and the cava filter was deployed. Postmortem autopsy was performed. Procedural success, guidewire visibility, pushability, and stent support were qualitatively assessed by consensus. Procedure times were documented. Guidewire guidance into the abdominal and thoracic aortas and the inferior vena cava was successful. Stent deployments were successful in the abdominal (swine 1) and thoracic (swine 2) segments of the descending aorta. Cava filter positioning and deployment was successful. Autopsy documented good stent and filter positioning. Guidewire visibility through applied markers was rated acceptable for aortic stenting and good for venous filter placement. Steerability, pushability, and device support were good. The PEEK-based guidewire allows either percutaneous MRI-guided aortic stenting in the thoracic and abdominal segments of the descending aorta and filter placement in the inferior vena cava with acceptable to good device visibility and offers good steerability, pushability, and device support.

  10. Stenting for a symptomatic posterior cerebral artery stenosis.

    PubMed

    Xu, Gelin; Zheng, Ling; Zhou, Zhiming; Liu, Xinfeng

    2009-05-01

    Evolvement of endovascular devices and increase of operator expertise have made angioplasty and stenting in intracranial vessels technically possible. Stenting has been reported in treating stenosis in middle and anterior cerebral arteries with favorable outcomes. However, the feasibility of stenting for stenosis in posterior cerebral artery (PCA) has not been established. We report a patient with progressive focal cerebral ischemic symptoms, which were arrested after reconstruction of the associated PCA stenosis with stenting.

  11. Broken Esophageal Stent Successfully Treated by Interventional Radiology Technique

    SciTech Connect

    Zelenak, Kamil; Mistuna, Dusan; Lucan, Jaroslav; Polacek, Hubert

    2010-06-15

    Esophageal stent fractures occur quite rarely. A 61-year-old male patient was previously treated for rupture of benign stenosis, occurring after dilatation, by implanting an esophageal stent. However, a year after implantation, the patient suffered from dysphagia caused by the broken esophageal stent. He was treated with the interventional radiology technique, whereby a second implantation of the esophageal stent was carried out quite successfully.

  12. A Migrated Aortic Stent Graft Causing Erosive Spondylopathy

    SciTech Connect

    Gestrich, Christopher Probst, Chris; Wilhelm, Kai; Schiller, Wolfgang

    2013-12-15

    We report about a patient presenting with back pain 4 months after an uneventful endovascular implantation of an aortic stent graft. Computed tomography scan revealed a migration of the stent with consecutive endoleakage, kink formation, and movement of the stent toward the spine, which caused destruction of the aortic wall as well as vertebral necrosis. Explantation of the stent and replacement of the native aorta relieved the patient of his symptoms.

  13. Treatment of Complex Intracranial Aneurysms Using Flow-Diverting Silk® Stents

    PubMed Central

    Buyukkaya, Ramazan; Kocaeli, Hasan; Yildirim, Nalan; Cebeci, Hakan; Erdogan, Cüneyt; Hakyemez, Bahattin

    2014-01-01

    Summary This study describes the peri-procedural and late complications and angiographic follow-up results of 32 patients with 34 complex aneurysms treated with flow diverter Silk stents in a single centre. In this retrospective study, 40 Silk stents (SS) were implanted in 34 complex intracranial aneurysms in 32 patients. In our series, 20 (58.8%) carotid-ophthalmic internal carotid artery (ICA), six (17.6%) cavernous ICA, two (5.9%) supraclinoid ICA, two (5.9%) petrosal ICA (the same patient- bilateral) and four (11.8%) posterior circulation aneurysms were treated. One of the posterior circulation lesions was a fenestrated-type aneurysm. Twenty wide-necked, saccular; eight neck remnant; four fusiform and two blister-like aneurysms were included in our series. SS were successfully implanted in all patients (100%). Misdeployment occurred in 17.6% of patients. In two of these patients adequate stent openness was achieved via Hyperglide balloon dilatation. Coil embolization in addition to SS placement was utilized in four aneurysms. One patient (3%) experienced transient morbidity due to a thromboembolic event and there was one mortality (3%) due to remote intraparenchymal haemorrhage. Complete occlusion of 27/33 (81.8 %) and 29/33 (87.9 %) aneurysms was achieved six and 12 months after the procedure, respectively. In-stent intimal hyperplasia was detected in 6.1 % patients. Flow-diverter Silk stent implantation is an effective method of treating complex aneurysms with acceptable mortality and morbidity rates. Complete occlusion is achieved in most of the complex aneurysms. PMID:25496683

  14. Stent recanalization of carotid tonsillar loop dissection using the Enterprise vascular reconstruction device

    PubMed Central

    Rahal, Jason P.; Gao, Bulang; Safain, Mina G.; Malek, Adel M.

    2014-01-01

    Although advances in endovascular techniques have permitted reconstruction of intimal dissections and related pseudoaneurysms of the extracranial cervical internal carotid artery, highly tortuous tonsillar loop anatomic variants still pose an obstacle to conventional extracranial self-expanding carotid stents. During a 12 year period, nine of 48 cases with cervical carotid dissections were associated with a tonsillar loop. Five patients required endovascular treatment, which was performed using a microcatheter-based technique with the low-profile Enterprise vascular reconstruction device (Codman Neurovascular, Raynham, MA, USA). Technical, radiographic, and clinical outcomes were analyzed for each patient. Dissection etiology was spontaneous in three patients, iatrogenic in one, and traumatic in one. Four near-occlusive tonsillar loop dissections were successfully recanalized during the acute phase. Dissection-related stenosis improved from 90 ± 22% to 31 ± 13%, with tandem stents needed in three instances to seal the inflow zone. There were no procedure-related transient ischemic attacks (TIA), minor/major strokes, or deaths. Angiographic follow-up with a mean of 28.0 ± 21.6 months showed all stents were patent, with average stenosis of 25.2 ± 12.2%. Focal ovalization and kinking of the closed-cell design was noted at the sharpest curve in one patient. Clinical outcome (follow-up of 28.1 ± 21.5 months) demonstrated overall improvement with no clinical worsening, new TIA, or stroke. Tonsillar loop-associated carotid dissections can be successfully and durably recanalized using the low-profile Enterprise stent with excellent long-term patency rate and low procedural risk. The possibility of stent kinking and low radial force should be considered when planning reconstruction with this device. PMID:24642024

  15. Radiological image-guided placement of covered Niti-S stent for palliation of dysphagia in patients with cervical esophageal cancer.

    PubMed

    Fujita, Takeshi; Tanabe, Masahiro; Shimizu, Kensaku; Iida, Etsushi; Matsunaga, Naofumi

    2013-06-01

    The aim of this study was to evaluate the clinical effectiveness of covered Niti-S stent placement under multidetector CT and fluoroscopy guidance for the palliation of dysphagia in patients with cervical esophageal cancer. Under radiological imaging guidance using axial and sagittal CT scans, and fluoroscopy, Niti-S esophageal stents were placed in ten consecutive patients with complete obstruction caused by cervical esophageal cancer (9 men and 1 woman; age range = 54-79 years; mean age = 68.1 years) between February 2010 and December 2011. The procedure time and technical success rate were evaluated. Swallowing improvement was assessed by the following items: ability to eat and/or swallow (graded as follows: 3 = ability to eat normal diet, 2 = ability to eat semisolids, 1 = ability to swallow liquids, 0 = complete obstruction). Procedural and post-procedural complications were also evaluated. Survival (mean ± SD) was examined. The mean (±SD) procedure time was 40 ± 19 min (range = 21-69 min). Stent placement was technically successful in all patients; inadequate stent deployment did not occur in any case. Ability to eat and/or swallow was improved and scored 2.4 (score 3 in 5 cases, score 2 in 4 cases, score 1 in 1 case, and score 0 in no case) after stent placement. No major or post-procedural complications were encountered. The mean survival time was 131 ± 77 days (range = 31-259 days). Niti-S stents appeared to be a safe and effective device for the palliation of dysphagia caused by advanced cervical esophageal cancer. Multidetector CT and fluoroscopy image guidance helped the operators accurately place the stents in the cervical esophagus.

  16. A simple technique to remove migrated esophageal stents.

    PubMed

    Noyer, C M; Forohar, F

    1998-09-01

    A 51-yr-old man with a tracheoesophageal fistula from an esophageal carcinoma had two expandable covered stents placed, which migrated distally. After several unsuccessful attempts to remove the stents, we fashioned a homemade snare to entrap and remove the stents under endoscopic and fluoroscopic guidance.

  17. Design of the Carotid Revascularization Endarterectomy vs. Stenting Trial (CREST)

    PubMed Central

    Sheffet, Alice J.; Roubin, Gary; Howard, George; Howard, Virginia; Moore, Wesley; Meschia, James F.; Hobson, Robert W.; Brott, Thomas G.

    2009-01-01

    Rationale Carotid endarterectomy (CEA) and medical therapy were shown superior to medical therapy alone for symptomatic (≥50%) and asymptomatic (≥60%) stenosis. Carotid angioplasty stenting (CAS) offers a less invasive alternative. Establishing safety, efficacy, and durability of CAS requires rigorous comparison with CEA in symptomatic and asymptomatic patients. Aims The objective is to compare the efficacy of CAS versus CEA in patients with symptomatic (≥50%) or asymptomatic (≥60%) extracranial carotid stenosis. Design The Carotid Revascularization Endarterectomy vs. Stenting Trial (CREST) is a prospective, randomized, parallel, two-arm, multi-center trial with blinded endpoint adjudication. Primary endpoints are analyzed using standard time-to-event statistical modeling with adjustment for major baseline covariates. Primary analysis is on an intent-to-treat basis. Study Outcomes The primary outcome is the occurrence of any stroke, myocardial infarction, or death during a 30-day peri-procedural period, and ipsilateral stroke during follow-up of up to four years. Secondary outcomes include restenosis and health-related quality of life. PMID:20088993

  18. Eptifibatide-induced thrombocytopenia leading to acute stent thrombosis.

    PubMed

    Dézsi, Döme A; Bokori, György; Faluközy, József; Bujáky, Csaba; Fogarassy, György; Veress, Gábor; Aradi, Dániel

    2016-04-01

    A 71-year old female patient with inferior ST-elevation myocardial infarction underwent primary percutaneous coronary intervention (PCI) within 3 h of symptom onset. She was preloaded with 300 mg aspirin and 600 mg clopidogrel before PCI. Coronary angiogram showed occlusion of the right coronary artery. During PCI, eptifibatide was initiated due to the large thrombus burden. Few hours after the procedure, on eptifibatide infusion, a severe drop in platelet count was observed (from 210,000/μl to 35,000/μl) and the infusion was discontinued. One hour later, still under eptifibatide effect and with severe thrombocytopenia, acute stent thrombosis developed. Lack of prior heparin exposure, quick onset of thrombocytopenia made heparin induced thrombocytopenia improbable that was later excluded by specific immunoassay. However, platelet function testing suggested that eptifibatide induced thrombocytopenia was mediated by activating autoantibodies since platelet reactivity was paradoxically very high at the time of stent thrombosis but decreased radically with eptifibatide washout. The patient was successfully managed without further complications on the basis of platelet function data obtained in the subsequent days. This rare subtype of thrombocytopenia highlights that not only platelet count but also platelet function should be closely monitored in case of severe thrombocytopenia to better balance bleeding and thrombosis.

  19. One Year Clinical Outcomes of Renal Artery Stenting: The Results of ODORI Registry

    PubMed Central

    Tamari, I.; Goffette, P.; Downes, M.; Senechal, Q.; Fanelli, F.; Reimer, P.; Negaiwi, Z.; De Cassin, P.; Heye, S.; Korobov, V.; Tsetis, D.; Abada, H.

    2009-01-01

    The safety, efficacy and long term clinical benefits of renal artery revascularization by stenting are still a matter of debate. The aim of our study was to define the safety and efficacy of renal artery stenting with the Tsunami peripheral stent (Terumo Corporation, Tokyo, Japan). The ODORI was a prospective, multicentre registry which enrolled 251 consecutive patients, (276 renal arteries) in 36 centres across Europe. The primary endpoint was acute procedural success defined as <30% residual stenosis after stent placement. Secondary endpoints included major adverse events, blood pressure control, serum creatinine level, and target lesion revascularization (TLR) at 6 and 12 months. Patients were 70 ± 10 years old, 59% were male, 33% had diabetes, and 96% hypertension. The main indications for renal stent implantation were hypertension in 83% and renal salvage in 39%. Direct stent implantation was performed in 76% of the cases. Acute success rate was 100% with residual stenosis of 2.5 ± 5.4%. Systolic/diastolic blood pressure decreased from a mean of 171/89 at baseline to 142/78 mmHg at 6 months (p < 0.0001 vs. baseline), and 141/80 mmHg at 12 months (p < 0.0001 vs. baseline). Mean serum creatinine concentration did not change significantly in the total population. However, there was significant improvement in the highest tercile (from 283 μmol/l at baseline to 205 and 209 μmol/l at 6 and 12 months respectively). At 12-months, rates of restenosis and TLR were 6.6 and 0.8% respectively. The 12 month cumulative rate of all major clinical adverse events was 6.4% while the rate of device or procedure related events was 2.4%. In hypertensive patients with atherosclerotic renal artery stenosis Tsunami peripheral balloon-expandable stent provides a safe revascularization strategy, with a potential beneficial impact on hypertension control and renal function in the highest risk patients. PMID:19908091

  20. Long-Term Clinical Outcomes Following Drug-eluting and Bare Metal Stenting in Massachusetts

    PubMed Central

    Mauri, Laura; Silbaugh, Treacy S; Wolf, Robert E; Zelevinsky, Katya; Lovett, Ann; Zhou, Zheng; Resnic, Frederic S; Normand, Sharon-Lise T

    2010-01-01

    Background Drug-eluting stents (DES) reduce the need for repeat revascularization, but their long term safety relative to bare metal stents (BMS) in general use remains uncertain. We sought to compare the clinical outcome of patients treated with DES vs. BMS. Methods and Results All adults undergoing percutaneous coronary intervention (PCI) with stenting between April 1, 2003 and September 30, 2004 at non-US governmental hospitals in Massachusetts were identified from a mandatory state database. Patients were classified according to stent types used from the index admission. Clinical and procedural risk factors were collected prospectively. Risk-adjusted mortality, myocardial infarction, and revascularization rate differences (DES-BMS) were estimated through propensity score matching without replacement. 11556 patients were treated with DES and 6237 treated with BMS with unadjusted 2 year mortality of 7.0% and 12.6% respectively (p<0.0001). In 5549 DES patients matched to 5549 BMS patients, 2 year risk-adjusted mortality rates were 9.8% and 12.0% (p=0.0002), myocardial infarction, 8.3% vs. 10.3% (p=0.0005), and target vessel revascularization, 11.0% vs. 16.8% (p<0.0001). Conclusions DES treatment was associated with lower mortality, myocardial infarction, and target vessel revascularization compared with BMS treatment in similar patients in a matched population based study. Comprehensive follow-up in this inclusive population is warranted to identify if similar safety and efficacy remain beyond 2 years. PMID:18852368

  1. Initial clinical experience with the trabecular micro-bypass stent in patients with glaucoma.

    PubMed

    Spiegel, Detlev; Wetzel, Wolfgang; Haffner, David S; Hill, Richard A

    2007-01-01

    This study was undertaken to evaluate the efficiency of a trabecular micro-bypass stent designed to allow direct aqueous drainage from the anterior chamber into Schlemm's canal in patients with glaucoma. In this prospective case series of 6 patients with open-angle glaucoma, the microstent was inserted ab interno under local anesthesia in an ophthalmic operating room. Patients were seen postoperatively at 1 to 2 d, 1 wk, and 1, 2, 6, and 12 mo. All stents were successfully placed within Schlemm's canal. Mean intraocular pressure (IOP) at preoperative baseline was 20.2+/-6.3 mm Hg (range, 14-31 mm Hg). Mean IOP decreased during the immediate postoperative period to approximately 12 to 13 mm Hg and was stabilized at 14 to 15 mm Hg with reduction of medication throughout 1 y of follow-up. No major complications occurred. According to observations reported in this feasibility study, the microstent was effective in reducing IOP and in decreasing the number of glaucoma medications required to control IOP. Implantation procedures were safe, and stents remained in place throughout the follow-up period. None of the complications traditionally associated with filtering surgery were reported. Further research on this stent in a larger group of patients is needed to assess its role in glaucoma therapy.

  2. Palliation of Postoperative Gastrointestinal Anastomotic Malignant Strictures with Flexible Covered Metallic Stents: Preliminary Results

    SciTech Connect

    Lee, Jeong-Min; Han, Young Min; Lee, Sang Yong; Kim, Chong Soo; Yang, Doo Hyun; Lee, Seung Ok

    2001-01-15

    Purpose: To evaluate the efficacy of the placement of covered metallic stents for palliation of gastrointestinal anastomotic strictures secondary to recurrent gastric cancer.Methods: Under fluoroscopic guidance, placement of one or two self-expandable covered metallic stents was attempted perorally in 11 patents (aged 48-76 years) with anastomotic stenoses due to recurrent gastric malignancies. The strictures involved both the afferent and efferent loops in three patients. All patients had poor peroral food intake with severe nausea and vomiting after ingestion. The technical and clinical success was evaluated.Results: Placement of the covered stent was technically successful in 13 of 15 (87%) attempts in ten patients. After the procedure, 9 of 11 (82%) patients overall were able to ingest at least a liquid diet and had markedly decreased incidence of vomiting. During the follow-up of 2-31 weeks (mean 8.5 weeks) there were no major complications.Conclusion: These preliminary results suggest that flexible, covered stents may provide effective palliation of malignant anastomotic stricture secondary to recurrent gastric cancer.

  3. Should plastic stents be avoided in all unresectable malignant perihilar biliary strictures?

    PubMed

    Kawashima, Hiroki; Itoh, Akihiro; Ohno, Eizaburo; Goto, Hidemi; Hirooka, Yoshiki

    2013-05-01

    Clinical guidelines of the European Society of Gastrointestinal Endoscopy recommend the insertion of self-expandable metallic stents (SEMS) as opposed to plastic stents (PS) in patients with unresectable malignant perihilar stricture (MHS). However, PS are cheaper and easier to insert into the biliary duct compared to SEMS. Furthermore, PS are removable and easy to move into subsequent drainage procedures. We conducted the present retrospective single-center study to elucidate the predictive factors associated with stent patency period duration in patients with unresectable MHS who would benefit from a long patency period after PS placement. This study included 56 consecutive patients with unresectable MHS who were drained using PS. PS failure occurred in 26 (46.4%) patients. The median patency period was 72 days (95% confidence interval: 29.8-114). The only significant predictive factor associated with the length of the stent patency period was history of previous endoscopic sphincterotomy (EST). Median patency periods with and without previous EST were 28 and 109 days, respectively (P = 0.016). In conclusion, we suggest that conventional biliary drainage with PS is still a suitable option for the treatment of unresectable MHS in patients without previous EST.

  4. Mechanical analysis of ovine and pediatric pulmonary artery for heart valve stent design.

    PubMed

    Cabrera, M S; Oomens, C W J; Bouten, C V C; Bogers, A J J C; Hoerstrup, S P; Baaijens, F P T

    2013-08-09

    Transcatheter heart valve replacement is an attractive and promising technique for congenital as well as acquired heart valve disease. In this procedure, the replacement valve is mounted in a stent that is expanded at the aimed valve position and fixated by clamping. However, for this technique to be appropriate for pediatric patients, the material properties of the host tissue need to be determined to design stents that can be optimized for this particular application. In this study we performed equibiaxial tensile tests on four adult ovine pulmonary artery walls and compared the outcomes with one pediatric pulmonary artery. Results show that the pediatric pulmonary artery was significantly thinner (1.06 ± 0.36 mm (mean ± SD)) than ovine tissue (2.85 ± 0.40 mm), considerably stiffer for strain values that exceed the physiological conditions (beyond 50% strain in the circumferential and 60% in the longitudinal direction), more anisotropic (with a significant difference in stiffness between the longitudinal and circumferential directions beyond 60% strain) and presented stronger non-linear stress-strain behavior at equivalent strains (beyond 26% strain) compared to ovine tissue. These discrepancies suggest that stents validated and optimized using the ovine pre-clinical model might not perform satisfactorily in pediatric patients. The material parameters derived from this study may be used to develop stent designs for both applications using computational models.

  5. Penetrating Atherosclerotic Ulcer of the Descending Thoracic Aorta: Treatment by Endovascular Stent-Graft

    SciTech Connect

    Murgo, Salvatore; Dussaussois, Luc; Golzarian, Jafar; Cavenaile, Jean Christophe; Abada, Hicham Tarik; Ferreira, Jose; Struyven, Julien

    1998-11-15

    Purpose: To present four cases of penetrating ulcer of the descending thoracic aorta treated by transfemoral insertion of an endoluminal stent-graft. Methods: Four patients with penetrating aortic ulcers were reviewed. Three cases were complicated by rupture, false aneurysm, or retrograde dissection. All patients were treated by endovascular stent-graft and were followed by helical computed tomography (CT). Results: Endovascular stent-graft deployment was successful in all patients. However, in one case we observed a perigraft leak that spontaneously disappeared within the first month, and two interventions were needed for another patient. Following treatment, one episode of transient spinal ischemia was observed. The 30-day survival rate was 100%, but one patient died from pneumonia with cardiac failure 34 days after the procedure. In one patient, helical CT performed at 3 months showed a false aneurysm independent of the first ulcer. This patient refused any further treatment and suddenly died at home (unknown cause) after a 6-month follow-up period. Conclusion: Transluminal placement of endovascular stent-grafts for treatment of penetrating ulcers of the descending thoracic aorta appears to be a possible alternative to classical surgery. After treatment, follow-up by CT is essential to detect possible complications of the disease.

  6. Effect of Variations in Stent Placement on Outcome of Endoluminal Stenting for Canine Tracheal Collapse.

    PubMed

    Rosenheck, Stephanie; Davis, Garrett; Sammarco, Carl D; Bastian, Richard

    2017-03-14

    The study's objective was to determine effects of relative size and placement location of endoluminal stents on incidence of complications and survival for canine tracheal collapse. Measurements were obtained on lateral radiographs before and after stenting to determine percent of the trachea occupied by the stent. These values were monitored over time and compared to complication rates and survival. Overall median survival time was 502 days. Six month survival rate was 78%, 1 yr survival was 60%, and 2 yr survival was 26%. Median percent of trachea occupied by the stent at initial placement was 79% (range, 41-93%). Percent of the trachea occupied by the stent at the time of placement did not significantly correlate to complication rate (0.397) or survival time (0.853). Incidence of serious complications was 37%, including granuloma formation, pneumonia, material failure, and stent migration. For patients experiencing serious complications, median survival was shorter, at 208 days, but was not significantly different from survival without serious complications. Within the margins of the data from this study, the proportion of the trachea occupied by the stent at the time of placement does not appear to impact incidence of complications or survival time in dogs with tracheal collapse.

  7. Stent hypersensitivity and infection in sinus cavities

    PubMed Central

    Soufras, George D.; Hahalis, George

    2013-01-01

    Persistent mucosal inflammation, granulation tissue formation, hypersensitivity, and multifactorial infection are newly described complications of retained drug-eluting stents from endoscopic sinus surgery for refractory rhinosinusitis. In an important report published in Allergy and Rhinology, a 45-year-old male patient suffering from recalcitrant chronic rhinosinusitis underwent functional endoscopic sinus surgery and was found, for the first time, to have steroid-eluting catheters that were inadvertently left in the ethmoid and frontal sinuses. The retained catheters had caused persistent mucosal inflammation and formation of granulation tissue denoting hypersensitivity reaction. These consequences had induced perpetuation of symptoms of chronic rhinosinusitis. Meticulous removal of the retained stents with the nitinol wings from inflamed tissues of the frontal, ethmoidal, and sphenoethmoidal recesses in which they were completely imbedded was successfully performed without polypoid regrowth. Cultures of specimens taken from both left and right stents showed heavy growth of Stenotrophomonas maltophilia and moderate growth of Klebsiella oxytoca, coagulase negative Staphylococcus, and beta-hemolytic Streptococcus anginosus. Fungal infection was not detected. The current knowledge and experience regarding stent hypersensitivity and infection in relation with the use of stents in sinus cavities is reviewed. PMID:24498522

  8. Palliative stenting for relief of dysphagia in patients with inoperable esophageal cancer: impact on quality of life.

    PubMed

    Madhusudhan, Chinthakandhi; Saluja, Sundeep S; Pal, Sujoy; Ahuja, Vineet; Saran, Pratap; Dash, Nihar R; Sahni, Peush; Chattopadhyay, Tushar K

    2009-01-01

    The aim of palliation in patients with inoperable esophageal cancer is to relieve dysphagia with minimal morbidity and mortality, and thus improve quality of life (QOL). The use of a self-expanding metal stent (SEMS) is a well-established modality for palliation of dysphagia in such patients. We assessed the QOL after palliative stenting in patients with inoperable esophageal cancer. Thirty-three patients with dysphagia due to inoperable esophageal cancer underwent SEMS insertion between October 2004 and December 2006. All patients had grade III/IV dysphagia and locally advanced unresectable cancer (n = 13), distant metastasis (n = 14), or comorbid conditions/poor general health status precluding a major surgical procedure (n = 6). Patients with grade I/II dysphagia and those with carcinoma of the cervical esophagus were excluded. The QOL was assessed using the European Organization for Research and Treatment of Cancer (EORTC) QLQ-C30 (version 3) and EORTC QLQ-Esophagus (OES) 18 questionnaire (a QOL scale specifically designed for esophageal diseases) before and at 1, 4, and 8 weeks after placement of the stent. The mean age of the patients was 56 (range 34-78) years, and 22 were men. A covered SEMS was used in all patients. The most common site of malignancy was the lower third of the esophagus (n = 18, 55%). In 23 (77%) patients, the stent crossed the gastroesophageal junction. Seven patients required a reintervention for stent block (n = 5) and stent migration (n = 2). Dysphagia improved significantly immediately after stenting, and this improvement persisted until 8 weeks (16.5 vs. 90.6; P < 0.01). The global health status (5.8 vs. 71.7; P < 0.01) and all functional scores improved significantly after stenting from baseline until 8 weeks. Except pain (14.1 vs. 17.7; P = 0.67), there was significant improvement in deglutition (22.7 vs. 2.0; P < 0.01), eating (48 vs. 12.6; P < 0.01), and other symptom scales (19.7 vs. 12.1; P = 0.04) following stenting. The

  9. The Use of Biodegradable Stents in Malignant Oesophageal Strictures for the Treatment of Dysphagia Before Neoadjuvant Treatment or Radical Radiotherapy: A Feasibility Study

    SciTech Connect

    Krokidis, Miltiadis Burke, Chris; Spiliopoulos, Stavros; Gkoutzios, Panos; Hynes, Orla; Ahmed, Irfan; Dourado, Renato; Sabharwal, Tarun; Mason, Robert; Adam, Andreas

    2013-08-01

    PurposeTo evaluate the clinical results of the use of biodegradable oesophageal stents in malignant strictures.MethodsEleven patients were included in this prospective analysis in which a woven polydioxanone biodegradable oesophageal stent was used. The inclusion criterion was that the patient underwent neoadjuvant treatment or radical radiotherapy after the stent insertion. Primary end points were dysphagia score at discharge, stent patency, and complication rate. Secondary end points were overall survival and surgical outcome of surgery.ResultsThere was a 100 % procedure technical success rate. Early complications occurred in three patients resulting in failure to restore oral nutrition. In the remaining eight patients, dysphagia was significantly improved at discharge. Mean stent patency rate in this group was 71.5 days. Stent dysfunction occurred in five of eight patients (62.5 %); in two of five patients this was due to local inflammatory reaction, and in three of five patients it was due to tumour growth after a mean time of 97.8 days, and a new metallic stent was consequently placed in four of five patients. One patient was successfully treated with esophagectomy. At the end of follow-up (mean time 102.1 days), three of eight stents were patent. The overall patient survival rate was 81.8 %.ConclusionAlthough short-term dysphagia scores improved, biodegradable stents do not appear to offer a clear beneficial effect in most cases of malignant strictures, particularly due to a local inflammatory reaction that may be induced. Technical improvement of the device and delineation of the patient group that would benefit from its use is necessary if further studies are to be conducted in the future.

  10. Complications and Follow-up after Unprotected Carotid Artery Stenting

    SciTech Connect

    Hauth, Elke A.M. Drescher, Robert; Jansen, Christian; Gissler, H. Martin; Schwarz, Michael; Forsting, Michael; Jaeger, Horst J.; Mathias, Klaus D.

    2006-08-15

    Purpose. This prospective study was undertaken to determine the success rate, complications, and outcome of carotid artery stenting (CAS) without the use of cerebral protection devices. Methods. During 12 months, 94 high-grade stenoses of the carotid artery in 91 consecutive patients were treated. Sixty-six (70%) of the stenoses were symptomatic and 28 (30%) were asymptomatic. Results. In all 94 carotid stenoses CAS was successfully performed. During the procedure and within the 30 days afterwards, there were 2 deaths and 3 major strokes in the 66 symptomatic patients, resulting in a combined death and stroke rate of 5 of 66 (7%). Only one of these complications, a major stroke, occurred during the procedure. In the 6-month follow-up, one additional major stroke occurred in a originally symptomatic patient resulting in a combined death and stroke rate of 6 of 66 (10%) for symptomatic patients at 6 months. No major complications occurred in asymptomatic patients during the procedure or in the 6-month follow-up period. At 6 months angiographic follow-up the restenosis rate with a degree of >50% was 3 of 49 (6%) and the rate with a degree of {>=}70% was 1 of 49 (2%). Conclusions. Cerebral embolization during CAS is not the only cause of the stroke and death rate associated with the procedure. The use of cerebral protection devices during the procedure may therefore not prevent all major complications following CAS.

  11. Intraluminal Radioactive Stent Compared with Covered Stent Alone for the Treatment of Malignant Esophageal Stricture

    SciTech Connect

    Wang Zhongmin; Huang Xunbo; Cao Jun; Huang Gang; Chen Kemin LIu Yu; Liu Fenju

    2012-04-15

    Objective: This study was designed to compare the clinical effectiveness of intraluminal radioactive stent loaded with iodine-125 seeds implantation versus covered stent alone insertion in patients with malignant esophageal stricture. Methods: We studied two groups of patients with malignant esophageal stricture. Group A comprised 28 patients (19 men and 9 women) who underwent intraluminal radioactive stent loaded with iodine-125 seeds implantation and were followed prospectively. Group B comprised 30 patients (18 men and 12 women) who had previously received covered stent alone insertion; these patients were evaluated retrospectively. There was no crossover between the two groups during follow-up. Informed consent was obtained from each patient, and our institutional review board approved the study. The dysphagia score, overall survival rates, complication rates, and reintervention rates were compared in the two groups. Results: There were no significant differences between the two groups in terms of baseline characteristics. Stent placement was technically successful and well tolerated in all patients. The dysphagia score was improved in both groups after stent placement. The median survival was significantly longer in group A than in group B: 11 versus 4.9 months, respectively (P < 0.001). The complications of chest pain, esophageal reflux, and stent migration was more frequent in group B, but this difference did not reach statistical significance. There was no statistical difference in reintervention between two groups. Conclusions: Intraluminal radioactive stent loaded with iodine-125 seeds implantation was a feasible and practical management in treating malignant esophageal stricture and was superior to covered stent alone insertion, as measured by survival.

  12. Basilar artery to bilateral posterior cerebral artery 'Y stenting' for endovascular reconstruction of wide-necked basilar apex aneurysms: report of three cases.

    PubMed

    Perez-Arjona, Eimir; Fessler, Richard D

    2004-04-01

    Endovascular reconstruction of basilar artery (BA) apex aneurysms has been augmented by adjunctive techniques such as balloon and stent assistance. We present three cases of a wide-necked BA apex aneurysm involving the bilateral P1 segments of both posterior cerebral arteries (PCAs) treated by placement of BA to PCA stents bilaterally in a 'Y' configuration to reconstruct the BA apex for effective coil embolization. Three patients (aged 70, 65 and 37 years) with wide-necked basilar artery aneurysms presented for endovascular treatment. All aneurysms had necks that involved the bilateral P1 segments. Each patient was deemed an appropriate candidate for endovascular reconstruction. Patients were pretreated with clopidogrel (75 mg) and aspirin (325 mg) each day for 3 days prior to the procedure. Following induction of general anesthesia, access to the right femoral artery was obtained by placement of a 6F sheath. Intravenous heparin was administered to achieve an activated coagulation time (ACT) of approximately 300 seconds. A 6F guide catheter was placed within the left vertebral artery (VA) in two patients, the right VA in a third. Utilizing over-the-wire (OTW) technique, a microcatheter was advanced into the left P2-P3 junction of the PCA. A 300-cm 0.014-inch microwire was passed through the microcatheter into the distal PCA and the microcatheter was removed. In each case, two neuroform stents were prepared (SMART Therapeutics Inc., San Leandro, CA) and advanced OTW into the PCA with the most acute angle relative to the BA. The initial stent placed was 20 mm in length and was deployed from the P1 segment into the BA. The microwire was pulled retrograde into the BA apex, then advanced though the stent struts and into the right PCA. A second stent, 15 mm in length, was advanced OTW through the struts of the previously placed stent. It was then deployed from the P1 into the BA where it overlapped the first stent, resulting in a stent-in-stent 'Y' configuration at the

  13. Experience with Biodegradable Polymer Coated Sirolimus-Eluting Coronary Stent System in “Real-Life” Percutaneous Coronary Intervention: 24-Month Data from the Manipal-S Registry

    PubMed Central

    Shetty, Ranjan; Vivek, G.; Thakkar, Ashok; Mishra, Supriya Sunder; Joseph, Vivek; Devraj, Mithun Gopal; Tumkur, Anil; Pai, Umesh

    2013-01-01

    Introduction: Despite the undeniable clinical efficacy of drug-eluting stents with durable polymers, concerns regarding their long-term safety have been raised, especially in more complex subsets. The Manipal-S Registry was designed to evaluate the safety and effectiveness of the biodegradable polymer coated Supralimus® Sirolimus-Eluting Coronary Stent for the treatment of coronary artery disease, across a wide range of patients who are treated in real-life clinical practice. Methods: All the consecutive 116 patients who underwent single-vessel or multiple vessel percutaneous coronary interventions with the use of Supralimus® sirolimus-eluting stents between September 2009 and December 2010, were included in this study. Patients were clinically followed-up at 1, 9, 12 and 24 months post-procedure. All clinical, procedural, and follow-up information were collected and analysed. Results: In total 116 patients, 126 lesions were implanted with 144 stents which had an average stent length of 25.8±8.0 mm. The incidences of any major adverse cardiac and cerebral events at 1, 9, 12 and 24 months were 0, 5 (4.3%), 8 (6.9%), and 10 (8.6%) respectively. Conclusion: These 24-month results clearly provide evidence for safety and effectiveness of the Supralimus® Sirolimus-eluting coronary stent system with the biodegradable polymer in real-life patients, even in those with acute myocardial infarctions. PMID:24179909

  14. Numerical Modeling of Nitinol Stent Oversizing in Arteries with Clinically Relevant Levels of Peripheral Arterial Disease: The Influence of Plaque Type on the Outcomes of Endovascular Therapy.

    PubMed

    Gökgöl, Can; Diehm, Nicolas; Büchler, Philippe

    2017-02-01

    Oversizing of the Nitinol stents in the femoro-popliteal arterial tract is commonly performed by clinicians and further encouraged by stent manufacturers. However, in spite of the procedure's supposed benefits of strong wall apposition and increased luminal gain, its effects on the mechanical behavior of arteries with peripheral arterial disease are not fully clear. In this study, finite element (FE) analyses of endovascular revascularization of an idealized artery with 70% stenosis and three different plaque types have been performed to examine the influence of Nitinol stent oversizing on the arterial stresses and acute lumen gain. The analyses included the simulation of balloon angioplasty to model plaque failure, followed by stent implantation, in which four different oversizing ratios were investigated. Results showed that balloon angioplasty was crucial in determining the stress levels of the artery prior to stent implantation and heavily affected the outcome of endovascular therapy. For all plaque types, Nitinol stent oversizing was found to produce a marginal lumen gain in contrast to a significant increase in arterial stresses. For the arteries with lightly and moderately calcified plaques, oversizing was found to be non-critical; whereas for the arteries with heavily calcified plaques, the procedure should be avoided due to a risk of tissue failure.

  15. Safety and efficacy of carbon dioxide and intravascular ultrasound-guided stenting for renal artery stenosis in patients with chronic renal insufficiency.

    PubMed

    Kawasaki, Daizo; Fujii, Kenichi; Fukunaga, Masashi; Fukuda, Nobuhisa; Masuyama, Tohru; Ohkubo, Nobukazu; Kato, Masaaki

    2015-03-01

    We evaluated the feasibility, safety, and mid-term outcomes of renal artery stenting using carbon dioxide (CO₂) digital subtraction angiography and intravascular ultrasound (IVUS) for patients with renal insufficiency and significant atherosclerotic renal artery stenosis (RAS). Eighteen consecutive patients with chronic renal insufficiency underwent renal artery stenting under the guidance of CO₂ angiography and IVUS without contrast media. Renal function and blood pressure were assessed pre- and postintervention. A total of 27 de novo RAS in 18 patients (15 males; mean age: 72 ± 9 years) with renal insufficiency were treated by renal artery stenting with the combined use of the CO₂ angiography and IVUS without any procedural complications. Although the mean serum creatinine concentration preprocedure and 6 months after treatment did not change (2.7 ± 1.0-2.4 ± 1.1 mg/dL), blood pressure significantly decreased 6 months after stenting (158 ± 10-147 ± 11 mm Hg, P < .01).

  16. Inverse Relationship between Serum VEGF Levels and Late In-Stent Restenosis of Drug-Eluting Stents

    PubMed Central

    Shen, Li; Ji, Meng; Cai, Sishi; Chen, Jiahui; Yao, Zhifeng

    2017-01-01

    Late in-stent restenosis (ISR) has raised concerns regarding the long-term efficacy of drug-eluting stents (DES). The role of vascular endothelial growth factor (VEGF) in the pathological process of ISR is controversial. This retrospective study aimed to investigate the relationship between serum VEGF levels and late ISR in patients with DES implantation. A total of 158 patients who underwent angiography follow-up beyond 1 year after intervention were included. The study population was classified into ISR and non-ISR groups. The ISR group was further divided according to follow-up duration and Mehran classification. VEGF levels were significantly lower in the ISR group than in the non-ISR group [96.34 (48.18, 174.14) versus 179.14 (93.59, 307.74) pg/mL, p < 0.0001]. Multivariate regression revealed that VEGF level, procedure age, and low-density lipoprotein cholesterol were independent risk factors for late ISR formation. Subgroup analysis demonstrated that VEGF levels were even lower in the very late (≥5 years) and diffuse ISR group (Mehran patterns II, III, and IV) than in the late ISR group (1–4 years) and the focal ISR group (Mehran pattern I), respectively. Furthermore, significant difference was found between diffuse and focal ISR groups. Serum VEGF levels were inversely associated with late ISR after DES implantation. PMID:28373989

  17. Is carotid sonography a useful tool for predicting functional capabilities in ischemic stroke patients following carotid artery stenting?

    PubMed Central

    Lin, Chih-Ming; Su, Jian-Chi; Chang, Yu-Jun; Liu, Chi-Kuang; Lu, Henry Horng-Shing; Jong, Yuh-Jyh

    2017-01-01

    Abstract Carotid stenosis is a major cause of stroke and timely intervention with stenting manipulation can significantly reduce the risk of secondary stroke. The impact of stenting procedures on patient functional capabilities has not yet been explored. The primary aim of this study was to examine associations between periprocedural carotid sonography parameters and post-treatment functional capabilities in stroke patients. Sixty-seven patients who received carotid stenting at 1 angiography laboratory were included. Prestenting and poststenting carotid duplex data were recorded and resistance index (RI) differences at various carotid system locations were compared. The modified Rankin Scale (mRS) was used to assess functional capability. All of the studied parameters were analyzed by SPSS (version 16.0, SPSS Inc, Chicago, IL). Following stenting, mRS scores improved (n = 44) or remained stationary (n = 23). Net contralateral internal carotid artery (ICA) RI for patients with improved mRS was lower compared to that for patients with stationary mRS (median = 0.040 vs 0.11; P = 0.003). The contralateral common carotid artery RI before and after stenting differed significantly (P < 0.050) in both. The ipsilateral ICA RI differed (P < 0.050) only in patients with improved mRS. The difference in mean transit time, Barthel index, net ipsilateral ICA RI, net contralateral external carotid artery RI, postipsilateral common carotid artery RI, and postipsilateral ICA RI differed significantly between different baseline stroke severity groups (P < 0.050). Carotid artery stenting improved physical function in a proportion of ischemic stroke patients with carotid stenosis. Carotid ultrasound is a useful assessment tool to predict likely functional outcomes following carotid artery stenting. PMID:28328821

  18. Stent Thrombosis: Incidence, Predictors and New Technologies

    PubMed Central

    Buchanan, Gill Louise; Basavarajaiah, Sandeep; Chieffo, Alaide

    2012-01-01

    Some concerns have been raised regarding the risk of late and very late stent thrombosis (ST) following drug-eluting stent implantation. Despite remaining an uncommon complication of percutaneous coronary intervention, when ST occurs, it can be catastrophic to the individual, commonly presenting as acute ST elevation myocardial infarction or sudden cardiac death. The incidence and predictors of ST have been reported in the literature and the role of dual antiplatelet therapies in the avoidance of such a complication remains vital. Ongoing studies are assessing the role of these therapies including platelet reactivity testing, genetic testing and optimum duration of therapy. In addition, newer polymer-free and bioabsorbable stents are under investigation in the quest to potentially minimise the risk of ST. PMID:22577541

  19. Stent optical inspection system calibration and performance.

    PubMed

    Bermudez, Carlos; Laguarta, Ferran; Cadevall, Cristina; Matilla, Aitor; Ibañez, Sergi; Artigas, Roger

    2017-03-20

    Implantable medical devices, such as stents, have to be inspected 100% so no defective ones are implanted into a human body. In this paper, a novel optical stent inspection system is presented. By the combination of a high numerical aperture microscope, a triple illumination system, a rotational stage, and a CMOS camera, unrolled sections of the outer and inner surfaces of the stent are obtained with high resolution at high speed with a line-scan approach. In this paper, a comparison between the conventional microscope image formation and this new approach is shown. A calibration process and the investigation of the error sources that lead to inaccuracies of the critical dimension measurements are presented.

  20. Nitinol Self-Expanding Stents for the Superficial Femoral Artery.

    PubMed

    Nathan, Ashwin; Kobayashi, Taisei; Giri, Jay

    2017-04-01

    The superficial femoral artery is a complex artery subject to a unique set of biomechanical loading conditions in its course through the leg. Plain balloon angioplasty and balloon-expandable stents had unacceptably high rates of restenosis, necessitating target vessel revascularization. Nitinol alloy is well suited to provide the strength and flexibility needed of stents to withstand the external forces posed by the environment of the superficial femoral artery. Advances in stent technology with the addition of a slow-releasing antiproliferative agent and changes in scaffold design have shown promise in reducing the rates of stent fracture and in-stent restenosis.

  1. Biofilm formation on ureteral stents - Incidence, clinical impact, and prevention.

    PubMed

    Zumstein, Valentin; Betschart, Patrick; Albrich, Werner C; Buhmann, Matthias T; Ren, Qun; Schmid, Hans-Peter; Abt, Dominik

    2017-02-06

    Ureteral stents are a simple, minimally invasive method of maintaining ureteral drainage to assure renal function, treat pain caused by ureteral obstruction and avoid external or visible devices. Ureteral stenting is, however, associated with a clear side-effect profile, including irritation on voiding, pain and haematuria. Complications such as stent dysfunction and clinically significant urinary tract infections are also regularly observed. Although this has not yet been thoroughly researched, it appears that biofilm formation on ureteral stents plays a key role in the associated morbidity. In this review, we summarise the current evidence and identify areas that should be further studied to reduce the morbidity associated with ureteral stenting.

  2. Percutaneous Transhepatic Biliary Metal Stent for Malignant Hilar Obstruction: Results and Predictive Factors for Efficacy in 159 Patients from a Single Center

    SciTech Connect

    Li, Mingwu Bai, Ming Qi, Xingshun Li, Kai Yin, Zhanxin; Wang, Jianhong; Wu, Wenbing Zhen, Luanluan He, Chuangye; Fan, Daiming; Zhang, Zhuoli; Han, Guohong E-mail: Hangh@fmmu.edu.cn

    2015-06-15

    AimTo investigate and compare the efficacy and safety of percutaneous transhepatic biliary stenting (PTBS) using a one- or two-stage procedure and determine the predictive factors for the efficacious treatment of malignant hilar obstruction (MHO).Methods159 consecutive patients with MHO who underwent PTBS were enrolled between January 2010 and June 2013. Patients were classified into one- or two-stage groups. Independent predictors of therapeutic success were evaluated using a logistic regression model.Results108 patients were treated with one-stage PTBS and 51 patients were treated with two-stage PTBS. The stents were technically successful in all patients. Successful drainage was achieved in 114 patients (71.4 %). A total of 42 early major complications were observed. Re-interventions were attempted in 23 patients during follow-up. The cumulative primary patency rates at 3, 6, and 12 months were 88, 71, and 48 %, respectively. Stent placement using a one- or two-stage procedure did not significantly affect therapeutic success, early major complications, median stent patency, or survival. A stent placed across the duodenal papilla was an independent predictor of therapeutic success (odds ratio = 0.262, 95 % confidence interval [0.107–0.642]). Patients with stents across papilla had a lower rate of cholangitis compared with patients who had a stent above papilla (7.1 vs. 20.3 %, respectively, p = 0.03).ConclusionsThe majority of patients with MHO who underwent one-stage PTBS showed similar efficacy and safety outcomes compared with those who underwent two-stage PTBS. Stent placement across the duodenal papilla was associated with a higher therapeutic success rate.

  3. Stent thrombosis and restenosis: what have we learned and where are we going? The Andreas Grüntzig Lecture ESC 2014

    PubMed Central

    Byrne, Robert A.; Joner, Michael; Kastrati, Adnan

    2015-01-01

    Modern-day stenting procedures leverage advances in pharmacotherapy and device innovation. Patients treated with contemporary antiplatelet agents, peri-procedural antithrombin therapy and new-generation drug-eluting stents (DES) have excellent outcomes over the short to medium term. Indeed, coupled with the reducing costs of these devices in most countries there remain very few indications where patients should be denied treatment with standard-of-care DES therapy. The two major causes of stent failure are stent thrombosis (ST) and in-stent restenosis (ISR). The incidence of both has reduced considerably in recent years. Current clinical registries and randomized trials with broad inclusion criteria show rates of ST at or <1% after 1 year and ∼0.2–0.4% per year thereafter; rates of clinical ISR are 5% respectively. Angiographic surveillance studies in large cohorts show rates of angiographic ISR of ∼10% with new-generation DES. The advent of high-resolution intracoronary imaging has shown that in many cases of late stent failure neoatherosclerotic change within the stented segment represents a final common pathway for both thrombotic and restenotic events. In future, a better understanding of the pathogenesis of this process may translate into improved late outcomes. Moreover, the predominance of non-stent-related disease as a cause of subsequent myocardial infarction during follow-up highlights the importance of lifestyle and pharmacological interventions targeted at modification of the underlying disease process. Finally, although recent developments focus on strategies which circumvent the need for chronically indwelling stents—such as drug-coated balloons or fully bioresorbable stents—more data are needed before the wider use of these therapies can be advocated. PMID:26417060

  4. Biomechanical Challenges to Polymeric Biodegradable Stents.

    PubMed

    Soares, Joao S; Moore, James E

    2016-02-01

    Biodegradable implants have demonstrated clinical success in simple applications (e.g., absorbable sutures) and have shown great potential in many other areas of interventional medicine, such as localized drug delivery, engineered tissue scaffolding, and structural implants. For endovascular stenting and musculoskeletal applications, they can serve as temporary mechanical support that provides a smooth stress-transfer from the degradable implant to the healing tissue. However, for more complex device geometries, in vivo environments, and evolving load-bearing functions, such as required for vascular stents, there are considerable challenges associated with the use of biodegradable materials. A biodegradable stent must restore blood flow and provide support for a predictable appropriate period to facilitate artery healing, and subsequently, fail safely and be absorbed in a controllable manner. Biodegradable polymers are typically weaker than metals currently employed to construct stents, so it is difficult to ensure sufficient strength to keep the artery open and alleviate symptoms acutely while keeping other design parameters within clinically acceptable ranges. These design challenges are serious, given the general lack of understanding of biodegradable polymer behavior and evolution in intimal operating conditions. The modus operandi is mainly empirical and relies heavily on trial-and-error methodologies burdened by difficult, resource-expensive, and time-consuming experiments. We are striving for theoretical advancements systematizing the empirical knowledge into rational frameworks that could be cast into in silico tools for simulation and product development optimization. These challenges are evident when one considers that there are no biodegradable stents on the US market despite more than 30 years of development efforts (and currently only a couple with CE mark). This review summarizes previous efforts at implementing biodegradable stents, discusses the

  5. Stent-Grafts in the Management of Hemorrhagic Complications Related to Hemostatic Closure Devices: Report of Two Cases

    SciTech Connect

    Giansante Abud, Daniel; Mounayer, Charbel; Saint-Maurice, Jean Pierre; Salles Rezende, Marco Tulio; Houdart, Emmanuel; Moret, Jacques

    2007-02-15

    We report 2 cases of hemorrhagic complications related to use of the Angio-Seal hemostatic closure device that were successfully managed with stent-grafts. Two patients with subarachnoid hemorrhage were referred to our departments for endovascular treatment of ruptured intracranial aneurysms. The treatment was performed through a femoral access; the sheaths were removed immediately after the procedures, and the punctures sites closed by Angio-Seals. Both patients presented clinical signs of hypovolemic shock after treatment. The diagnosis of active bleeding through the puncture site was made by emergency digital subtraction angiography. The lesions were managed with stent-grafts. The use of stent-grafts proved to be efficient in the management of these life-threatening hemorrhagic complications following the use of the Angio-Seal hemostatic closure device.

  6. Fast Virtual Stenting with Active Contour Models in Intracranical Aneurysm

    PubMed Central

    Zhong, Jingru; Long, Yunling; Yan, Huagang; Meng, Qianqian; Zhao, Jing; Zhang, Ying; Yang, Xinjian; Li, Haiyun

    2016-01-01

    Intracranial stents are becoming increasingly a useful option in the treatment of intracranial aneurysms (IAs). Image simulation of the releasing stent configuration together with computational fluid dynamics (CFD) simulation prior to intervention will help surgeons optimize intervention scheme. This paper proposed a fast virtual stenting of IAs based on active contour model (ACM) which was able to virtually release stents within any patient-specific shaped vessel and aneurysm models built on real medical image data. In this method, an initial stent mesh was generated along the centerline of the parent artery without the need for registration between the stent contour and the vessel. Additionally, the diameter of the initial stent volumetric mesh was set to the maximum inscribed sphere diameter of the parent artery to improve the stenting accuracy and save computational cost. At last, a novel criterion for terminating virtual stent expanding that was based on the collision detection of the axis aligned bounding boxes was applied, making the stent expansion free of edge effect. The experiment results of the virtual stenting and the corresponding CFD simulations exhibited the efficacy and accuracy of the ACM based method, which are valuable to intervention scheme selection and therapy plan confirmation. PMID:26876026

  7. Recent developments in drug-eluting coronary stents.

    PubMed

    Yildiz, Mustafa; Yildiz, Banu Sahin; Gursoy, Mustafa Ozan; Akin, Ibrahim

    2014-01-01

    The interventional treatment of coronary artery disease was introduced in 1970`s by Andreas Grüntzig. The initial treatment strategy with plain old balloon angioplasty (POBA) was associated with high restenosis rates. The introduction of coronary stents, especially drug-eluting stents (DES) in 2002 has improved the results by lowering the rate of in-stent restenosis from 20-40% in the era of bare-metal stent (BMS) to 6-8%. However, in 2006 with the observation of late stent thrombosis the reputations of DES have decreased. However, improvements in stent design especially antiproliferative agents, polymeric agents as well as stent platforms improved newer generation DES. In controlled trials as well as registries the use of second-generation DES as compared to bare-metal stents (BMS) was associated with better clinical and angiographic results. A further development of these stents with use of biodegradable polymers, polymer-free stents, and biodegradable stents on the basis of poly L-lactide (PLLA) or magnesium resulted in third-generation DES and has been evaluated in preclinical and first clinical trials. However, to date, there is a lack of data comparing these third-generation DES with first- and second-generatrion DES in a large scale.

  8. Elastic recoil of coronary stents: a comparative analysis.

    PubMed

    Barragan, P; Rieu, R; Garitey, V; Roquebert, P O; Sainsous, J; Silvestri, M; Bayet, G

    2000-05-01

    Minimum elastic recoil (ER) has became an essential feature of new coronary stents when deployed in artheromatous lesions of various morphologies. The ER of coronary stent might be an important component of 6-month restenosis rate by minimizing the luminal loss. We evaluated the intrinsic ER of 23 coronary stents with a mechanical test bench. The amount of ER for one size of stent (3.0 mm) was quantified using a 3D optical contactless machine (Smartscope MVP, Rochester, NY). The stents were expanded on their own balloon for the precrimped stents; the uncrimped stents were expended using identical 3.0-mm balloons. Two types of measurements were done without exterior stress and with a 0.2-bar exterior stress, directly on the stent at the end of balloon expansion, immediately after balloon deflation, and then 30 min, 60 min, and 120 min after. ER ranged from 1.54%+/-0.81% (Bestent BES 15) to 16.51%+/-2.89% (Paragon stent) without stress (P<0.01) and from 2.35%+/-1.14% (Bestent BES 15) to 18.34%+/-2.41% (Cook GR2) under 0.2-bar pressure (P<0.0001). Furthermore, there was a significant reduction between the mean result of tubular stents (TS) and coil stents (CS). The results of in vitro mechanical tests may confirm strongly the interest of a minimum ER in the prevention of the 6-month restenosis.

  9. Application of physician-modified fenestrated stent graft in urgent endovascular repair of abdominal aortic aneurysm with hostile neck anatomy

    PubMed Central

    Zeng, Rong; Ye, Wei; Liu, Changwei; Wang, Xuan; Song, Xiaojun; Ni, Leng; Liu, Bao; Li, Yongjun; Zheng, Yuehong

    2016-01-01

    Abstract Background: This study aimed to evaluate the feasibility and effectiveness of the Gore Excluder aortic stent graft (WL Gore & Associates, Inc., Flagstaff, AZ) using the C3 Delivery System after physician modification of fenestration for the urgent treatment of patients with abdominal aortic aneurysm showing hostile neck anatomy. Case summary: Three urgent cases of abdominal aortic aneurysm with hostile neck anatomy symptom with abdominal pain were reported. The same fenestration method was applied to align the target superior mesenteric artery and bilateral renal arteries with 1 scallop and 2 fenestrations, followed by the reconstruction of the target artery using a bare-metal stent or stent graft. Balloon-assisted positioning and image fusion technology were intraoperatively applied to assist the accurate release of the stent graft body. The follow-up periods for all cases exceeded 6 months, showing smooth circulation in the target arteries with no endoleaks. Conclusion: In the absence of other available treatment methods, it is feasible to use a stent graft with physician-modified fenestration for the urgent endovascular repair of abdominal aortic aneurysm with hostile neck anatomy. However, this procedure's long-term efficacy needs to be further investigated. PMID:27861397

  10. Spontaneous Solitaire™ AB Thrombectomy Stent Detachment During Stroke Treatment

    SciTech Connect

    Akpinar, Suha Yilmaz, Guliz

    2015-04-15

    Spontaneous Solitaire™ stent retriever detachment is a rarely defined entity seen during stroke treatment, which can result in a disastrous clinical outcome if it cannot be solved within a critical stroke treatment time window. Two solutions to this problem are presented in the literature. The first is to leave the stent in place and apply angioplasty to the detached stent, while the second involves surgically removing the stent from the location at which it detached. Here, we present a case of inadvertent stent detachment during stroke treatment for a middle cerebral artery M1 occlusion resulting in progressive thrombosis. The detached stent was removed endovascularly by another Solitaire stent, resulting in the recanalization of the occluded middle cerebral artery.

  11. Iliac Artery Injury Following Placement of the Memotherm Arterial Stent

    SciTech Connect

    Redman, Alan; Cope, Lance; Uberoi, Raman

    2001-03-15

    Iliac rupture and aneurysm formation at the site of stent placement has rarely been described in the literature. We report four cases, three of iliac rupture, including a delayed rupture, and an aneurysm, with the use of a single type of stent, the Memotherm stent. We believe the design of the stent significantly contributed to damage to the arterial wall and subsequently prevented closure of the arterial tear by balloon tamponade in the two cases where this was attempted. Two patients, one with rupture and one with an aneurysm, were successfully treated with a covered stent obviating surgery and two ruptures resulted in death. We recommend that all interventionists carrying out iliac angioplasty and/or stenting should have access to covered stents for such emergencies.

  12. Everolimus-eluting stents: update on current clinical studies.

    PubMed

    Allocco, Dominic J; Joshi, Anita A; Dawkins, Keith D

    2011-01-01

    Everolimus-eluting stents (EES) have become the most commonly implanted coronary stents worldwide. This review describes and analyzes the clinical data supporting the use of EES, focusing primarily on published, randomized, controlled trials. Everolimus-eluting stents have been shown to have less restenosis, stent thrombosis, and periprocedural myocardial infarction compared with earlier generation paclitaxel-eluting stents (PES). Lower rates of adverse events for EES compared with PES were generally seen in all subgroups, with the notable exception of patients with diabetes mellitus. There have been fewer, randomized, clinical trials comparing EES with either sirolimus-eluting stents or zotarolimus-eluting stents, although very good results with EES have been observed in the trials that have been performed. Recent clinical trial data suggest that this excellent safety and efficacy profile is maintained in a next-generation EES designed to have improved mechanical properties and radiopacity.

  13. Role of stents and laser therapy in biliary strictures

    NASA Astrophysics Data System (ADS)

    Chennupati, Raja S.; Trowers, Eugene A.

    2001-05-01

    The most frequent primary cancers causing malignant obstructive jaundice were pancreatic cancer (57%), hilar biliary cancer (19% including metastatic disease), nonhilar biliary cancer (14%) and papillary cancer (10%). Endoscopic stenting has widely replaced palliative surgery for malignant biliary obstruction because of its lower risk and cost. Self-expandable metal stents are the preferred mode of palliation for hilar malignancies. Plastic stents have a major role in benign biliary strictures. Major complications and disadvantages associated with metallic stents include high cost, cholangitis. malposition, migration, unextractability, and breakage of the stents, pancreatitis and stent dysfunction. Dysfunction due to tumor ingrowth can be relieved by thermal methods (argon plasma coagulator therapy). We present a concise review of the efficacy of metallic stents for palliation of malignant strictures.

  14. Stent graft placement for a tracheoinnominate artery fistula.

    PubMed

    Troutman, Douglas A; Dougherty, Matthew J; Spivack, Adam I; Calligaro, Keith D

    2014-05-01

    A 68-year-old woman with ventilator-dependent respiratory failure and multiple comorbidities developed acute massive hemoptysis. Computed tomographic angiogram revealed a 3.9-cm pseudoaneurysm arising from the innominate artery abutting the trachea. The patient was successfully treated with stent graft insertion via the right common carotid artery, with exclusion of the aneurysm from the proximal innominate to the right common carotid artery, with ligation of the proximal right subclavian artery and right common carotid to subclavian artery bypass. The patient remained medically stable for 3 months after the procedure with no evidence of endoleak or infection. She then developed recurrent hemoptysis with fatal cardiac arrest. Open surgical repair has been the treatment of choice for tracheoinnominate artery fistula. However, direct repair confers a high mortality risk. Endovascular exclusion offers a less invasive treatment option for tracheoinnominate artery fistula and can serve as a bridge for patients with potential for becoming better surgical candidates.

  15. Emergency Stenting of a Ruptured Infected Anastomotic Femoral Pseudoaneurysm

    SciTech Connect

    Klonaris, Chris Katsargyris, Athanasios; Matthaiou, Alexandros; Giannopoulos, Athanasios; Tsigris, Chris; Papadopouli, Katerina; Tsiodras, Sotiris; Bastounis, Elias

    2007-11-15

    A 74-year-old man presented with a ruptured infected anastomotic femoral pseudoaneurysm. Due to severe medical comorbidities he was considered unsuitable for conventional surgical management and underwent an emergency endovascular repair with a balloon-expandable covered stent. The pseudoaneurysm was excluded successfully and the patient had an uneventful postoperative recovery with long-term suppressive antimicrobials. He remained well for 10 months after the procedure with no signs of recurrent local or systemic infection and finally died from an acute myocardial infarction. To our knowledge, emergency endovascular treatment of a free ruptured bleeding femoral artery pseudoaneurysm has not been documented before in the English literature. This case illustrates that endovascular therapy may be a safe and efficient alternative in the emergent management of ruptured infected anastomotic femoral artery pseudoaneurysms when traditional open surgery is contraindicated.

  16. Coronary stenting during burn shock: diagnostic and treatment considerations.

    PubMed

    Gregg, Shea C; Fidler, Philip E; Atweh, Nabil A

    2006-01-01

    Myocardial injury is known to occur in victims of both thermal and electrical burns. A variety of mechanisms have been ascribed to the pathogenesis of cardiac damage during burn shock. However, limited evidence exists that coronary artery thrombosis plays a frequent role. Distinguishing between acute coronary syndrome (impending myocardial infarction from coronary artery occlusion) vs global cardiac injury is essential; the care diverges drastically. The following case describes a patient who was angiographically proven to have acute coronary thrombosis amidst burn shock ftera 50% TBSA electrical flash burn. Managing the patient's burn shock, myocardial injury, and multiple surgical procedures while considering anti