nitinol and Aortic-Dissection

This article provides a brief update on the current status of the treatment of thoracic aortic pathology using the Medtronic Talent device. Preoperative evaluation and selection criterion along with study design are described for the recently completed Phase II VALOR Trial (Evaluation of the Medtronic AVE Talent Thoracic Stent Graft System for the Treatment of Thoracic Aneurysms). In addition, the results of several recent series for the treatment of degenerative aneurysm and more complex aortic pathology such as transection, rupture and acute and chronic dissection are reviewed.

Topics: Alloys; Angiography; Aortic Aneurysm, Abdominal; Aortic Aneurysm, Thoracic; Aortic Dissection; Blood Vessel Prosthesis; Blood Vessel Prosthesis Implantation; Clinical Trials as Topic; Female; Humans; Male; Minimally Invasive Surgical Procedures; Patient Selection; Polyethylene Terephthalates; Prosthesis Design; Stents; Treatment Outcome

Prosthesis infection after aortic surgery is a critical complication that most commonly requires surgical treatment with removal of the infected material. In this video tutorial, we remove a novel nitinol wire braided stent. It was introduced to stabilize the true lumen and prevent distal anastomotic new entry. Both the stent type and surgical approach were new and therefore constituted a major challenge. Despite these issues, removal with bilateral subclavian and femoral cannulation under hypothermic circulatory arrest proved successful.

Topics: Alloys; Aorta, Thoracic; Aortic Aneurysm, Thoracic; Aortic Dissection; Blood Vessel Prosthesis Implantation; Humans; Postoperative Complications; Stents; Treatment Outcome

Thoracic endovascular aortic repair (TEVAR) has been accepted as the mainstream treatment for type B aortic dissection, but post-TEVAR biomechanical-related complications are still a major drawback. Unfortunately, the stent-graft (SG) configuration after implantation and biomechanical interactions between the SG and local aorta are usually unknown prior to a TEVAR procedure. The ability to obtain such information via personalised computational simulation would greatly assist clinicians in pre-surgical planning. In this study, a virtual SG deployment simulation framework was developed for the treatment for a complicated aortic dissection case. It incorporates patient-specific anatomical information based on pre-TEVAR CT angiographic images, details of the SG design and the mechanical properties of the stent wire, graft and dissected aorta. Hyperelastic material parameters for the aortic wall were determined based on uniaxial tensile testing performed on aortic tissue samples taken from type B aortic dissection patients. Pre-stress conditions of the aortic wall and the action of blood pressure were also accounted for. The simulated post-TEVAR configuration was compared with follow-up CT scans, demonstrating good agreement with mean deviations of 5.8% in local open area and 4.6 mm in stent strut position. Deployment of the SG increased the maximum principal stress by 24.30 kPa in the narrowed true lumen but reduced the stress by 31.38 kPa in the entry tear region where there was an aneurysmal expansion. Comparisons of simulation results with different levels of model complexity suggested that pre-stress of the aortic wall and blood pressure inside the SG should be included in order to accurately predict the deformation of the deployed SG.

Topics: Adult; Alloys; Aorta; Aortic Dissection; Blood Vessel Prosthesis Implantation; Computed Tomography Angiography; Computer Simulation; Elasticity; Endovascular Procedures; Female; Humans; Models, Cardiovascular; Reproducibility of Results; Stents; Stress, Mechanical

Topics: Alloys; Animals; Aorta, Thoracic; Aortic Aneurysm, Thoracic; Aortic Dissection; Blood Vessel Prosthesis; Blood Vessel Prosthesis Implantation; Disease Models, Animal; Dogs; Humans; Postoperative Complications; Prosthesis Design; Self Expandable Metallic Stents; Time Factors; Tomography, X-Ray Computed; Treatment Outcome

Aortic bare-metal stent rupture is an exceptional complication, associated with high risk of aorta rupture and death. We describe a successful endovascular approach for a symptomatic aortic bare-metal stent fracture after the provisional extension to induce complete attachment (PETTICOAT) technique.. A 53-year-old man with a complicated type B aortic dissection (visceral malperfusion) was treated with thoracic endovascular aortic repair (TEVAR) and "PETTICOAT" technique. The 1-, 6-, and 12-month follow-up scans showed progressive aortic remodeling. After 15 months from the initial procedure, the patient was admitted to the emergency department with severe thoracic pain and two syncopal episodes. Urgent angio-computed tomography (CT) showed bare-metal stent rupture and aortic dilatation to 45 mm at the site of stent fracture.. He was urgently treated with TEVAR to cover the entire length of the bare-metal stent under local anesthesia and motor-evoked potential (MEP) monitoring. If signs of medullary ischemia are observed in the MEP register, a carotid-subclavian bypass was planned. At 12 months of follow-up, the patient remains asymptomatic. CT scan at 1 month and 12 months showed no signs of endoleak and aortic remodeling to 40 mm.. Although unusual, this case demonstrates the possibility of material fatigue/failure and highlights the need of close imaging follow-up after TEVAR for treatment of aortic diseases.

Topics: Alloys; Aortic Aneurysm, Thoracic; Aortic Dissection; Aortography; Blood Vessel Prosthesis; Blood Vessel Prosthesis Implantation; Computed Tomography Angiography; Endovascular Procedures; Humans; Male; Middle Aged; Prosthesis Design; Prosthesis Failure; Reoperation; Self Expandable Metallic Stents; Treatment Outcome

Provisional Extension To Induce Complete Attachment (PETTICOAT) technique has shown good results in the treatment of acute type B aortic dissections (ABAD). Usually, uncovered tubular stainless steel stents are used to promote distal true lumen reattachment.. We describe the Petticoat technique using a conic self-expanding nitinol device as distal uncovered stent in five cases of complicated ABAD. We used as distal uncovered stent the single-flared E-XL (Jotec-GmbH).. In one case, renal arteries were successfully stented through the large cells of the E-XL. No perioperative complications were reported. During follow-up (18-24 months), positive remodeling of the entire aorta occurred in 3 cases; in 1 case with associated thoracoabdominal aneurysm, false lumen thrombosis at the thoracic level with true lumen expansion at the visceral aorta was detected at the 18-month CT angiogram, and in 1 patient with Marfan syndrome, open surgical conversion with the E-XL explantation was performed after 24 months due to aneurysmal evolution at the visceral level.. The E-XL can be successfully used in ABAD. It adapts to different aortic diameters, and its major radial force promotes successful positive remodeling. The open cell structure allows visceral arteries stenting, and it can be removed without complications during open conversion.

Topics: Adult; Aged; Alloys; Aortic Aneurysm; Aortic Dissection; Aortography; Blood Vessel Prosthesis; Blood Vessel Prosthesis Implantation; Computed Tomography Angiography; Endovascular Procedures; Female; Humans; Male; Middle Aged; Prosthesis Design; Self Expandable Metallic Stents; Time Factors; Treatment Outcome

The frozen elephant procedure, as a hybrid method to treat aortic pathologies involving the aortic arch and the proximal descending aorta, has become an accepted treatment option. We report two late fractures of the nitinol stents of the endograft of an early frozen elephant trunk prosthesis. One patient suffered from a tear of the woven polyester fabric, causing a Type III endoleak and rapid progression of the existing descending aortic aneurysm. The patient received replacement of the descending aorta. The second patient showed a fracture of a nitinol stent without further complications during follow-up.

Topics: Alloys; Aortic Aneurysm, Thoracic; Aortic Dissection; Blood Vessel Prosthesis Implantation; Computed Tomography Angiography; Endoleak; Humans; Prosthesis Design; Prosthesis Failure; Stents

Chronic dissection of proximal aortic neck is a rare occurrence in patients with abdominal aortic aneurysm (AAA) and a gold standard therapy has not been defined so far. Herein we report two successful cases of an original adjunctive procedure involving the transrenal placement of a self-expanding nitinol stent (E-XL aortic stent, Jotec GmbH, Germany) in order to fix a dissection flap in the aortic neck wall prior to the deployment of the bifurcated endograft. Primary technical success and midterm clinical success was achieved in both cases with freedom from any early or late reintervention. Scheduled follow-up angio-CT scans did not show any Type I endoleak, graft migration or renal/visceral arteries complications. According to these findings, patients with an AAA, presenting with a proximal neck with chronic dissection, can be safely and effectively treated by pre-emptive transrenal E-XL stenting and endovascular aneurysm repair.

Topics: Aged; Aged, 80 and over; Alloys; Aortic Aneurysm, Abdominal; Aortic Dissection; Aortography; Blood Vessel Prosthesis; Blood Vessel Prosthesis Implantation; Endovascular Procedures; Humans; Male; Prosthesis Design; Stents; Tomography, X-Ray Computed; Treatment Outcome

Persistent retrograde false lumen perfusion is a common mode of failure after thoracic endovascular aortic repair (TEVAR) for chronic dissection. Objectives were to describe a novel endovascular approach for false lumen occlusion and assess outcomes.. From 2009 to 2013, 21 patients (mean age, 64 ± 11 years) with chronic thoracoabdominal dissection underwent adjunctive false lumen embolization using covered stent devices for persistent retrograde perfusion. Eight patients had type B dissection, 13 had residual dissection after prior type A repair, and all were deemed high risk for open operation. False lumen embolization in 17 patients was an adjunct at the initial TEVAR or extension, including two as elephant trunk completion. In the other four, this was done as an isolated procedure, and three had previously undergone TEVAR sparing the celiac artery. Covered stent devices included iliac plugs in 18, nitinol embolization plugs in two, and occluded stent graft in one. More than one device was used in 15 patients.. There was one hospital death due to left subclavian artery aneurysm rupture but no patient had stroke, paraplegia, myocardial infarction, or renal failure. Mean follow-up was 25 ± 19 months. During surveillance computed tomography imaging, false lumen thrombosis was noted in all patients, but four required further embolization because the thrombosis was incomplete. Mean maximum aortic diameter decreased from 64 ± 14 to 59 ± 15 mm. There was one late death from intracranial hemorrhage and no aortic ruptures.. Adjunctive false lumen embolization with a covered stent device promotes thrombosis and remodeling after stent grafting the true lumen for chronic dissection. Further study of this strategy is warranted.

Topics: Aged; Alloys; Aortic Aneurysm, Thoracic; Aortic Dissection; Aortography; Chronic Disease; Embolization, Therapeutic; Endovascular Procedures; Female; Humans; Male; Middle Aged; Prosthesis Design; Stents; Thrombosis; Time Factors; Tomography, X-Ray Computed; Treatment Outcome; Vascular Remodeling

In magnetic resonance imaging, implantable devices are usually visualized with a negative contrast. Recently, positive contrast techniques have been proposed, such as susceptibility gradient mapping (SGM). However, SGM reduces the spatial resolution making positive visualization of small structures difficult. Here, a development of SGM using the original resolution (SUMO) is presented. For this, a filter is applied in k-space and the signal amplitude is analyzed in the image domain to determine quantitatively the susceptibility gradient for each pixel. It is shown in simulations and experiments that SUMO results in a better visualization of small structures in comparison to SGM. SUMO is applied to patient datasets for visualization of stent and prostate brachytherapy seeds. In addition, SUMO also provides quantitative information about the number of prostate brachytherapy seeds. The method might be extended to application for visualization of other interventional devices, and, like SGM, it might also be used to visualize magnetically labelled cells.

Topics: Alloys; Aortic Aneurysm, Thoracic; Aortic Dissection; Brachytherapy; Computer Simulation; Gadolinium; Humans; Imaging, Three-Dimensional; Magnetic Resonance Imaging; Male; Models, Theoretical; Organometallic Compounds; Phantoms, Imaging; Prostatic Neoplasms; Software; Stents

The treatment of complex aortic pathologies involving the ascending aorta, the aortic arch, and the descending aorta remains a challenging issue in aortic surgery. The frozen elephant trunk procedure effectively combines surgical and interventional technologies in the treatment of extensive aortic aneurysms and dissections. We present two patients with complex aortic lesions involving all three segments of the thoracic aorta. The device used in our series is the new E-vita open hybrid prosthesis consisting of a proximal woven polyester tube and a distal self-expandable nitinol stent graft, which can be delivered antegrade into the descending aorta.

Topics: Alloys; Aortic Aneurysm, Thoracic; Aortic Dissection; Blood Vessel Prosthesis Implantation; Female; Humans; Middle Aged; Polyethylene Terephthalates; Prosthesis Design; Stents; Tomography, X-Ray Computed; Treatment Outcome

In this retrospective study we reviewed our results of secondary surgery for complications after emergency placement of aortic stents for acute type B dissection. From October 2000 to June 2006, endovascular stent-grafting (ESG) was performed in 13 patients as an emergency procedure for acute type B dissection. Self-expanding nitinol stents (mean diameter 39.8+/-4.7 mm) were placed into the descending aorta distal to the left subclavian artery. In-hospital mortality was 15.4% (2/13) and related to persistent visceral malperfusion. Three patients (23%) required consecutive open surgery of the thoracic aorta after emergency endovascular stent-grafting for acute type B dissection. Indications for surgery included acute development of retrograde type A aortic dissection and acute stent dislocation by fractured wires and secondary leakage. Elective surgery was necessary in one patient 6 months after stent-grafting for late formation of an aneurysm of the descending aorta. There were no deaths or major morbidity after surgery of the thoracic aorta early or during follow-up. Mean follow-up was 38.0+/-13.9 months (range 1-70 months) and complete. We conclude from our study that stent-grafting of the descending aorta is a feasible, relatively safe and effective approach even in the emergency treatment of patients with complicated acute type B dissection. However, in a relevant number of patients emergency stent-grafting for acute type B aortic dissection results in complications that require secondary surgical treatment.

Topics: Aged; Alloys; Aortic Aneurysm, Thoracic; Aortic Dissection; Blood Vessel Prosthesis Implantation; Emergencies; Female; Follow-Up Studies; Humans; Male; Middle Aged; Retrospective Studies; Stents; Tomography, X-Ray Computed; Treatment Outcome

Evaluation of the use of covered stents in treating pseudoaneurysms of the cervical and intracranial/extradural carotid artery and determination of the periprocedural and short- to mid-term complication rate.. 8 patients with 9 spontaneous dissecting aneurysms of the cervical carotid artery--5 of which were symptomatic--plus one patient with ofthalmoplegia due to an aneurysm of the cavernous carotid artery were studied. While the latter was treated with a PTFE-covered balloon-mounted stainless steel stent (Jostent/Graftmaster), a self-expanding PTFE-covered Nitonol Stent (Symbiot) was used in all other cases. Intervention was performed with local anesthesia. Aspirin and Clopidogrel were both used as antiplatelet drugs. Clinical signs and symptoms and vascular imaging with DS, MR, CT angiography and ultrasound were recorded during patient follow-up, with a mean follow-up period of 14.6 months (4 - 30).. We were able to treat 8 out of 10 aneurysms (80%) using covered stents. The aneurysms were immediately occluded and the associated stenoses of the parent vessel were eliminated. No clinically relevant complications occurred during the procedure or in the follow-up interval. In two cases, elongation of the carotid artery prevented the stent from being positioned over the aneurysm neck. These cases were shown to be stable with the use of antiplatelet drugs.. Covered stents can be used in the treatment of pseudoaneurysms of the carotid artery as an alternative to long-term antithrombotic medication or surgery. In our study treatment was effective (80%) and free of complications in the short- and mid-term follow-up. Possible indications, technique and the use of imaging modalities for patient follow-up are discussed.

Topics: Adult; Alloys; Angiography, Digital Subtraction; Angioplasty; Aortic Dissection; Aspirin; Carotid Artery Diseases; Carotid Artery, External; Cerebral Angiography; Clopidogrel; Female; Follow-Up Studies; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Platelet Aggregation Inhibitors; Polytetrafluoroethylene; Stents; Ticlopidine; Time Factors; Tomography, X-Ray Computed; Treatment Outcome

This registry aims at evaluating the use and efficacy of the EndoFit stent graft (LeMaitre Vascular, Burlington MA, USA) for the treatment of acute and chronic aortic type B dissections.. Indications for treatment are: recurrent pain, persistent hypertension, serious organ malperfusion in patients with acute or subacute type B aortic dissection and progression of aneurysm size despite maximal medical therapy in patient with chronic type B dissection. Exclusion criteria are: age under 18 years old, pregnancy, coagulopathy or bleeding disorders, connective tissue disease. Straight or tapered EndoFit stent graft will be used in acute or chronical dissection respectively.. The primary endpoint is the assessment of the safety and the efficacy of the EndoFit Thoracic Endoluminal Stent Graft in the exclusion of the thoracic aortic false lumen in acute and chronic type B aortic dissections. The assessment includes: technical success, thrombosis of the thoracic false lumen at 6 months, rate of aorto-enteric, aorto-esophageal and aorto-bronchial fistula, serious adverse events including death, stroke, paraplegia, myocardial infarction, multi-organ failure and renal insufficiency. Secondary endpoints are: the technical feasibility of device implantation in 2 different shapes (straight for acute dissection and tapered for chronic dissection), the technical feasibility of endovascular placement of tapered grafts in vessels of different size and shape, the integrity of the device fabric and wire structure, the occurrence of device migration, the patient's neurological, cardiac and cardiovascular status, the blood flow supply to abdominal and visceral organs arteries and any secondary intervention including stentgraft extension, coiling or surgical conversion. One hundred patients enrolled have been defined to allow reliable findings and results.. The DEDICATED is the first prospective data collection registry focusing on the role of tapered stentgrafts in chronic aortic dissection and their efficacy in excluding the dissected thoracic false lumen.

Topics: Acute Disease; Alloys; Aortic Aneurysm, Thoracic; Aortic Dissection; Blood Vessel Prosthesis; Chronic Disease; Disease Progression; Europe; Humans; Pilot Projects; Polytetrafluoroethylene; Prospective Studies; Prosthesis Design; Registries; Safety; Stents; Treatment Outcome

New devices for endovascular treatment of thoracic aortic diseases were recently approved for clinical use by European authorities, obtaining the Conformité Européenne (CE) mark. In all patients who underwent endovascular treatment of a thoracic aortic disease in 2002, we used a new CE-marked device, the Endofit stent graft. The device is constituted of nitinol stents and polytetrafluoroethylene fabric, and has a simple design and delivery system.. During 2002, 11 patients (mean age, 75 years; range, 66-85 years) underwent treatment of atherosclerotic aneurysm (n = 9), chronic type B dissection (n = 1), and intramural hematoma (n = 1). Disease involved the descending thoracic aorta in 7 patients and the distal aortic arch in 4 patients.. In all cases the Endofit stent grafts were successfully deployed in the intended position. No postoperative paraplegia or paraparesis was recorded. There were two in-hospital deaths: 1 patient died in the operating room (postmortem examination showed a kinked graft); and the other patient died in the intensive care unit on postoperative day 30, after an intraoperative stroke. One surgical conversion was performed 2 weeks after the procedure, because of total collapse of the graft due to rupture of three stents. Other graft-related complications included type I endoleak (n = 2), type II endoleak (n = 1), and incomplete opening of the device (n = 1).. Endovascular treatment of thoracic disease with the Endofit graft in this small heterogeneous group of patients resulted in several complications, which may arise from both the delivery system and the graft itself. At present, other commercially available endografts may be safer for endovascular treatment of thoracic aortic diseases.

Topics: Aged; Aged, 80 and over; Alloys; Aortic Aneurysm, Thoracic; Aortic Dissection; Arteriosclerosis; Blood Vessel Prosthesis; Blood Vessel Prosthesis Implantation; Female; Humans; Male; Polytetrafluoroethylene; Prosthesis Design; Prosthesis Failure; Radiography; Stents

To report our experience using a commercially available catheter-based system equipped with an intravascular ultrasound (IVUS) transducer to achieve controlled true lumen re-entry in patients undergoing subintimal angioplasty for chronic total occlusions (CTO) or aortic dissections.. During an 8-month period, 10 patients (6 men; mean age 73.4 years) with lower extremity (LE) ischemia from CTOs (n=7) or true lumen collapse from aortic dissections (n=3) were treated. Subintimal access and controlled re-entry of the CTOs were performed with a commercially available 6.2-F dual-lumen catheter, which contained an integrated 64-element phased-array IVUS transducer and a deployable 24-G needle through which a guidewire was passed once the target lumen was reached. The occluded segments were balloon dilated; self-expanding nitinol stents were deployed. In the aortic dissections, fenestrations were performed using the same device, with the IVUS unit acting as the guide. The fenestrations were balloon dilated and stented to support the true lumen.. Time to effective re-entry ranged from 6 to 10 minutes (mean 7) in the CTOs; antegrade flow was restored in all 7 CTOs, and the patients were free of ischemic symptoms at up to 8-month follow-up. In the aortic dissection cases, the fenestrations equalized pressures between the lumens and restored flow into the compromised vessels. There were no complications related to the use of this device in any of the 10 patients.. Our preliminary results demonstrate the feasibility of using this catheter-based system for subintimal recanalization with controlled re-entry in CTOs and for aortic flap fenestrations in aortic dissections. This approach can improve the technical success rate, reduce the time of the procedure, and minimize potential complications.

Topics: Aged; Aged, 80 and over; Alloys; Angioplasty, Balloon; Aortic Aneurysm, Abdominal; Aortic Dissection; Arterial Occlusive Diseases; Cost Savings; Female; Humans; Ischemia; Leg; Male; Middle Aged; Stents; Transducers; Treatment Outcome; Tunica Intima; Ultrasonography, Interventional

To report the midterm results of the endovascular treatment of complicated type-B aortic dissection with use of stent-grafts.. Ten patients with acute (n = 4) or chronic (n = 6) complicated type-B dissection were treated with custom-made stent-grafts. Indications for treatment included uncontrollable hypertension with dissection extension (n = 3), renal ischemia (n = 1), and false lumen aneurysm (n = 6). Stainless-steel Z-stents covered with polyester grafts were placed in the initial six patients. Nitinol stents covered with ultrathin polytetrafluoroethylene were used in the remaining four patients. The patients were followed-up with helical computed tomography for a maximum of 30 months (mean, 20 mo).. There was one technical failure related to the access site. Early complications included deep venous thrombosis (n = 1) and embolic stroke (n = 1). Complete thrombosis of the thoracic false lumen was achieved in six patients and partial thrombosis was achieved in three. Aneurysms developed at the ends of the stainless-steel stents in two patients, requiring additional stent-graft placement. Despite successful remodeling of the thoracic aorta, three of four patients with distal reentry into the abdominal aorta experienced progressive abdominal aortic aneurysm (AAA). AAA rupture developed in two patients; one rupture was fatal and the other was treated with emergency surgery.. Endovascular treatment of complicated type-B aortic dissection is technically feasible and effective. Closely monitoring the treated aorta is essential to detect early aneurysm formation at the ends of rigid stents. Despite adequate sealing of the tears in the thoracic aorta, dissection with distal reentry phenomenon into the abdominal aorta may evolve into AAA with late rupture.

Topics: Alloys; Aortic Aneurysm; Aortic Dissection; Blood Vessel Prosthesis Implantation; Equipment Design; Female; Follow-Up Studies; Humans; Male; Middle Aged; Polytetrafluoroethylene; Stainless Steel; Stents; Time Factors; Tomography, X-Ray Computed

The objective of this study was to compare contrast-enhanced magnetic resonance angiography (CE MRA) and multislice computed tomographic angiography (MS CTA) in the follow-up of thoracic stent-graft placement. The CE MRA and MS CTA were performed following nitinol stent-graft treatment due to thoracic aneurysm ( n=4), intramural bleeding ( n=2) and type-B aortic dissection ( n=5). Corresponding evaluation of arterial-phase imaging characteristics focused on the stent-graft morphology and leakage assessment. Stent-graft and aneurysm extensions were comparable between both techniques. Complete exclusion (aneurysm, n=4; dissection, n=2) was assessed with high confidence with CE MRA and MS CTA. Incomplete exclusion (intramural bleeding, n=2; dissection, n=3) was assigned to lower confidence scores on CE MRA compared with MS CTA. On CE MRA the stent-graft lumen demonstrated an inhomogeneous signal, the stent struts could not be assessed. The CE MRA can be used as alternative non-invasive imaging for follow-up of nitinol stent grafts. Arterial-phase leak assessment can be less evident in CE MRA compared with MS CTA studies; therefore, the use of late-phase imaging seems to be necessary. The diagnostic gap of stent-graft fracture evaluation using MRA may be filled with plain radiographs.

Topics: Aged; Alloys; Angiography; Aortic Aneurysm, Thoracic; Aortic Dissection; Blood Vessel Prosthesis Implantation; Contrast Media; Female; Follow-Up Studies; Gadolinium; Humans; Imaging, Three-Dimensional; Iohexol; Magnetic Resonance Angiography; Male; Organometallic Compounds; Stents; Tomography, X-Ray Computed

Percutaneous peripheral interventional procedures as well as coronary interventions can be complicated by dissections and traumatic lesions of peripheral arteries. The aim of this study was to evaluate the efficacy of fabric covered endoprostheses for percutaneous repair of traumatic peripheral arterial lesions.. In this study we used the EndoPro 1/Passager device (Boston Scientific, USA), which is a self-expanding nitinol stent covered by an ultrathin layer of dacron fabric. In 27 patients a total number of 31 endoprostheses (mean length 7.3 cm) were implanted in iliac (n = 20), femoral (n = 6) and popliteal arteries (n = 1). Indications for stenting were large dissections (n = 24), arterial perforations (n = 2) and one traumatic arterio-venous fistula.. An immediate exclusion of the lesion could be achieved in all cases. There were no major procedural complications. However, within 24 hours after implantation 14 patients (51.9%) developed fever. WBC and CRP were elevated in 13 (48.1%) and 17 (63%) patients, respectively. Repeated blood cultures could not show any bacterial growth. The primary patency after a mean follow-up of 19 (5 to 31) months was 85.2%. In two cases with markedly impaired peripheral run-off subacute graft occlusions occurred. In 2 other cases the angiography revealed relevant restenoses (> 75%). The patency could be restored in 2 of these 4 cases leading to a secondary patency rate of 92.6%.. The EndoPro 1/Passager endoprosthesis seems to be safe and effective to seal large dissections and traumatic lesions of peripheral arteries, showing a high long-term patency rate.

Topics: Adult; Aged; Alloys; Angiography; Angioplasty, Balloon; Aortic Dissection; Coated Materials, Biocompatible; Equipment Failure Analysis; Female; Femoral Artery; Graft Occlusion, Vascular; Humans; Iliac Artery; Male; Middle Aged; Polyethylene Terephthalates; Popliteal Artery; Retreatment; Stents; Systemic Inflammatory Response Syndrome

This study was designed to evaluate the potential obliteration of an experimental aortic dissection using an intravascular stent introduced via the femoral artery. Twenty-two adult dogs were divided into four groups: in group A (n = 6) a thoracoabdominal aortic dissection was surgically created to observe the natural course of this lesion; in group B (n = 6) a nitinol coil graft was introduced into the aorta via the femoral artery; in group C (n = 3) a nitinol coil graft was introduced via the femoral artery into a dissected aorta in an attempt to obliterate the dissection; and in group D (n = 7) an expandable intraluminal vascular graft (Palmaz stent) was introduced via the femoral artery into a dissected aorta in an attempt to obliterate the dissection. Arteriographic evaluation was performed postoperatively and again 6 weeks later before the aortas were explanted. Gross and light microscopic examinations were performed on all explanted aortas. In group A dissection was achieved and a postoperative aortogram demonstrated evidence of aortic dissection in all animals. Autopsy revealed persistence of dissection with a reentry tear near the celiac axis in five animals. In group B there was incomplete expansion of the nitinol coil graft in five dogs, resulting in aortic thrombosis in one. In group C the nitinol coil graft failed to obliterate the aortic dissection in all animals and resulted in aortic thrombosis in two. In group D placement of a balloon-expandable intraluminal stent solely at entry and reentry sites resulted in only partial obliteration of the dissection (n = 3), but when the entire length of the dissected aorta was treated, the dissection was completely obliterated (n = 3).

Topics: Acute Disease; Alloys; Animals; Aortic Aneurysm, Abdominal; Aortic Aneurysm, Thoracic; Aortic Dissection; Blood Vessel Prosthesis; Constriction; Dogs; Femoral Artery; Materials Testing; Models, Biological; Polytetrafluoroethylene; Prosthesis Design; Radiography; Stents; Treatment Outcome; Tunica Intima