nitinol and Aortic-Aneurysm--Thoracic

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

The authors present etiology, diagnosis and operative treatment of thoracoabdominal aneurysms based on their own experiences, especially in performing proximal anastomosis between vascular graft and aorta. The protheses are made of polytertafluoroethylene or dacron. They are impregnated with colagen or soaked with argentum or antibiotics. Spinal cord and visceral organ protection is described. The authors present also endovascular treatment of aorta. Internal chasis of vascular protheses (stentgrafts) is made of biologically neutral metal (like stainless stell, nitinol, other alloys). Its diameter is simmilar to abdominal or thoracic aorta dimension. The chasis is covered by material used also to produce classic vascular protheses (polytetrafluoroethylene, dacron). Thoracoabdominal aneurysms occur rarely, but they are the most difficult problem in vascular surgery. According to literature occurrence of aneurysms in this section value from 4% to 10%. Atherosclerotic process is a exciting cause of this type of aneurysms. According to modified Crawfords classification there are five basic types of thoracoabdominal aneurysms. For pioneer of thoracoabdominal aneurysms surgical treatment one should to recognize S. Etheredge, who in 1954 as a first performed human, aortal homograft implantation with using temporary by-pass. In 1973 E. S. Crawford proposed a new way of management depended on in situ anastomosis between arterial trunks with prosthesis, without use of temporary bypass. In Anglo-Saxon literature this technique gained descriptive qualification "clamp and sew". Using this method, thoracoabdominal aneurysms surgery stood himself decidedly shorter and safer for patients.

Topics: Alloys; Aortic Aneurysm, Abdominal; Aortic Aneurysm, Thoracic; Arteriovenous Shunt, Surgical; Blood Vessel Prosthesis; Blood Vessel Prosthesis Implantation; Humans; Intraoperative Complications; Polytetrafluoroethylene; Postoperative Complications; Risk Factors; Stents; Survival Rate; Vascular Surgical Procedures

This study compared midterm results using low-profile stent grafts (LPSGs; 18F) and standard-profile stent grafts (SPSGs; 22F-24F) for endovascular pararenal and thoracoabdominal aortic aneurysm (TAAA) repair.. From July 2005 to March 2015, 134 asymptomatic patients underwent endovascular repair of a pararenal or TAAA using multibranched aortic stent grafts. In March 2011, we started using a LPSG with nitinol stents and thin-walled polyester fabric. Prospectively collected data on operative repair, complications, and outcomes were compared between the two groups.. LPSGs were used in 37 patients (8 women [21.6%]; mean ± standard deviation age, 72.5 ± 8 years) and SPSGs in 97 patients (25 [26%] women; mean age, 73 ± 8 years). Medical comorbidities, aneurysm size, and aneurysm extent were similar in the LPSG and SPSG groups. Mean follow-up time was longer in the SPSG group (3.1 ± 2 years) than in the LPSG group (1.3 ± 0.9 years; P < .001). Operative time, renal failure, stroke, myocardial infarction, and perioperative death were not significantly different between the two groups (P > .05). Aneurysm-related death, rupture, stent graft migration, type I or III endoleaks, aneurysm enlargement >5 mm, branch vessel occlusion, and reintervention rates were similar between the two groups (P > .05). However, the combined outcome of conduit use or access artery injury occurred at a lower rate in the LPSG group than in the SPSG group (16% vs 36%; P = .03). Women experienced significantly higher rates of conduit use and access artery injury than men after repair with SPSGs (64% vs 26%, respectively; P = .001) but similar rates after repair with the LPSG (25% vs 14%, respectively; P = .45).. LPSGs had similar safety profile and midterm outcomes compared with the SPSGs for treatment of pararenal and TAAA. The substitution of LPSGs for SPSGs lowered the number of patients who required conduit insertion to avoid access artery injury, especially in women, thereby reducing an otherwise striking gender difference.

Topics: Aged; Aged, 80 and over; Alloys; Aortic Aneurysm, Abdominal; Aortic Aneurysm, Thoracic; Blood Vessel Prosthesis; Blood Vessel Prosthesis Implantation; Endovascular Procedures; Female; Healthcare Disparities; Humans; Male; Middle Aged; Polyesters; Postoperative Complications; Prospective Studies; Prosthesis Design; Risk Factors; San Francisco; Sex Factors; Stents; Time Factors; 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

To characterize the short-term results of a newly available self-expanding covered stent (Covera; CR Bard Peripheral Vascular Inc., Murray Hill, New Jersey) for the reconstruction of target vessels in complex aneurysms.. From August 2017 to November 2018, this self-expanding covered stent was used in 17 patients (mean 72.6 ± 7.6 years of age) during endovascular aneurysm repair (EVAR) with hypogastric preservation (11.8%), branched EVAR (29.4%), fenestrated (F)-EVAR (17.6%), chimney + F-EVAR (11.8%), or chimney EVAR (29.4%). In more than 48 stented arteries (2.8 ± 1.1/patient), 25 were preserved using this self-expanding covered stent.. All target vessels were successfully preserved. There was no 30-day mortality and 1 in-hospital death. Intraoperative aneurysm exclusion was successful in 14 patients (82.4%) with a perioperative technical success rate of 82.4%. The actuarial survival rate was 93.8% at 6 months and 85.9% at 12 months. Aneurysm sac regression of >5 mm was observed in 4 cases (23.5%), and the sac remained stable in the remaining patients (13 cases [76.5%]). At 12 months, the primary clinical success rate was 76.5%, and assisted primary clinical success rate was 82.4%. No type 3 endoleak was related to a disruption of the reconstruction with the self-expanding covered stent.. This new self-expanding covered stent provides good short-term patency in chimneys, branches, or fenestrations. Larger series with long-term follow-up are required to determine if the stent can sustain the mechanical stress to which it will be submitted in these repairs.

Topics: Aged; Aged, 80 and over; Alloys; Aortic Aneurysm, Abdominal; Aortic Aneurysm, Thoracic; Blood Vessel Prosthesis; Blood Vessel Prosthesis Implantation; Endovascular Procedures; Female; Hospital Mortality; Humans; Male; Prosthesis Design; Retrospective Studies; Self Expandable Metallic Stents; Time Factors; Treatment Outcome; Vascular Patency

To evaluate the Covera Plus (Bard, Tempe, Arizona) covered stent as a bridging stent in branched thoraco-abdominal endovascular aneurysm repair (BEVAR).. Retrospective analysis of 112 self-expandable stents was performed at 2 university centers between August 2017 and March 2019. Thirty-one consecutive BEVAR procedures were studied (21 males; mean age, 75 years; 29 American Society of Anesthesiologists grade III/IV) with 119 patent target vessels (7 did not receive the studied device). Primary endpoints were technical success, branch instability, and primary/secondary clinical success. Secondary endpoints included primary/secondary patency and any adverse events.. Technical success was 100%. Median follow-up was 12 months (interquartile range, 6-14 months). Branch instability was registered twice (2/112), due to immediate renal occlusion and type Ic endoleak; no additional events occurred during the follow-up. Primary clinical success was 84%. There were 2 immediate deaths, 1 upper limb ischemia, 1 hemorrhage from splenic artery, and 1 type Ic endoleak; these last 3 events were successfully treated, with a secondary clinical success of 100% that was maintained during the follow-up. One late death occurred. Primary patency was 99% (111/112) and 100% (105/105) within 30 days and at the end of the study period,respectively. Adverse events included 4 acute kidney injuries and 2 spinal cord ischemia. No type I/III endoleaks, occlusion, fracture, or dislodging were diagnosed after 30 days.. The stent graft seems safe and effective for bridging in BEVAR with low branch instability and high patency rate. Longer follow-up is required to confirm these promising results.

Topics: Aged; Alloys; Aortic Aneurysm, Thoracic; Blood Vessel Prosthesis; Blood Vessel Prosthesis Implantation; Endovascular Procedures; Female; Humans; Italy; Male; Postoperative Complications; Prosthesis Design; Retreatment; Retrospective Studies; Risk Factors; Self Expandable Metallic Stents; Time Factors; Treatment Outcome; Vascular Patency

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

A 71-year old man with previous thoracic aneurysm endovascular repair and endovascular abdominal aneurysm repair presented with simultaneous type III endoleak from the thoracic components and type Ia endoleak from migration of the abdominal endograft, leading to enlargement of both aneurysms. A custom-made reverse tapered Relay NBS thoracic endograft was used to bridge the thoracic stent grafts. While a low-flow type III endoleak persisted in the immediate postoperative phase, because of incomplete apposition of the new stent graft, further deployment of its nitinol skeleton resulted in resolution of the endoleak at 1-week follow-up. The abdominal aneurysm enlargement was corrected via excision of the central segment of the abdominal endograft, preservation of the distal main body and limbs, and interposition of a short Dacron tube graft.

Topics: Aged; Alloys; Aortic Aneurysm, Abdominal; Aortic Aneurysm, Thoracic; Aortography; Blood Vessel Prosthesis; Blood Vessel Prosthesis Implantation; Computed Tomography Angiography; Endoleak; Endovascular Procedures; Foreign-Body Migration; Humans; Male; Polyethylene Terephthalates; Prosthesis Design; Prosthesis Failure; Stents; 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

The ideal stent combination for chimney endovascular aneurysm repair remains undetermined. Therefore, we sought to identify optimal aortic and chimney stent combinations that are associated with the best outcomes by analyzing the worldwide collected experience in the PERformance of chImney technique for the treatment of Complex aortic pathoLogiES (PERICLES) registry.. The PERICLES registry was reviewed for patients with pararenal aortic disease electively treated from 2008 to 2014. Eleven different aortic devices were identified with three distinct subgroups: group A (n = 224), nitinol/polyester; group B (n = 105), stainless steel/polyester; and group C (n = 69), nitinol/expanded polytetrafluoroethylene. The various chimney stent subtypes included the balloon-expandable covered stent (BECS), self-expanding covered stent, and bare-metal stent. Deidentified aortic and chimney device combinations were compared for risk of chimney occlusion, type IA endoleak, and survival. Effects of high-volume centers (>100 cases), use of an internal lining chimney stent, number of chimney stents, and number of chimney stent subtypes deployed were also considered. We considered demographics, comorbidities, and aortic anatomic features as potential confounders in all models.. The 1- and 3-year freedom from BECS chimney occlusion was not different between groups (group A, 96% ± 2% and 87% ± 5%; groups B and C, 93% ± 3% and 76% ± 10%; Cox model, P = .33). Similarly, when non-BECS chimney stents were used, no difference in occlusion risk was noted for the three aortic device groupings; however, group C patients receiving BECS did have a trend toward higher occlusion risk relative to group C patients not receiving a BECS chimney stent (hazard ratio [HR], 4.0; 95% confidence interval [CI], 0.85-18.84; P = .08). Patients receiving multiple chimney stents, irrespective of stent subtype, had a 1.8-fold increased risk of occlusion for each additional stent (HR, 1.8; 95% CI, 1.2-2.9; P = .01). Use of a bare-metal endolining stent doubled the occlusion hazard (HR, 2.1; 95% CI, 1.0-4.5; P = .05). Risk of type IA endoleak (intraoperatively and postoperatively) did not significantly differ for the aortic devices with BECS use; however, group C patients had higher risk relative to groups A/B without BECS (C vs B: odds ratio [OR], 3.2 [95% CI, 1-11; P = .05]; C vs A/B: OR, 2.4 [95% CI, 0.9-6.4; P = .08]). Patients treated at high-volume centers had significantly lower odds for development of type IA endoleak (OR, 0.2; 95% CI, 0.1-0.7; P = .01) irrespective of aortic or chimney device combination. Mortality risk was significantly higher in group C + BECS vs group A + BECS (HR, 5.3; 95% CI, 1.6-17.5; P = .006). The 1- and 3-year survival for groups A, B, and C (+BECS) was as follows: group A, 97% ± 1% and 92% ± 3%; group B, 93% ± 3% and 83% ± 7%; and group C, 84% ± 7% and 63% ± 14%. Use of more than one chimney subtype was associated with increased mortality (HR, 3.2; 95% CI, 1.4-7.5; P = .006).. Within the PERICLES registry, use of nitinol/polyester stent graft devices with BECS during chimney endovascular aneurysm repair is associated with improved survival compared with other aortic endografts. However, this advantage was not observed for non-BECS repairs. Repairs incorporating multiple chimney subtypes were also associated with increased mortality risk. Importantly, increasing chimney stent number and bare-metal endolining stents increase chimney occlusion risk, whereas patients treated at low-volume centers have higher risk of type IA endoleak.

Topics: Aged; Aged, 80 and over; Alloys; Aortic Aneurysm, Abdominal; Aortic Aneurysm, Thoracic; Blood Vessel Prosthesis; Blood Vessel Prosthesis Implantation; Comorbidity; Disease-Free Survival; Endoleak; Endovascular Procedures; Europe; Female; Graft Occlusion, Vascular; Hospitals, High-Volume; Hospitals, Low-Volume; Humans; Male; Multivariate Analysis; Odds Ratio; Polyesters; Polytetrafluoroethylene; Proportional Hazards Models; Prosthesis Design; Registries; Retrospective Studies; Risk Factors; Stainless Steel; Stents; Time Factors; Treatment Outcome; United States

Purpose Our objective was to compare the radial forces of several stents ex vivo to identify stents suitable for rescue of the unexpected coverage of aortic arch branches in thoracic endovascular aortic repair. Methods We measured the radial forces of two types of self-expanding bare nitinol stents (E-luminexx and Epic) used singly or as double-walled pairs, and of three endoprostheses used in thoracic endovascular aortic repair (TEVAR, Gore c-TAG, Relay, and Valiant) by compressing the stent using an MTS Instron universal testing machine (model #5582). We also examined the compressive effects of the TEVAR endoprostheses and the bare nitinol stents on each other. Results The radial force was greater in the center than at the edge of each stent. In all stents tested, the radial force decreased incrementally with increasing stent diameter. The radial force at the center was two times greater when using two stents than with a single stent. In the compression test, only E-luminexx used as a pair was not compressed after compressing a Relay endoprosthesis by 12 mm. Conclusion Two E-luminexx stents are appropriate to restore the blood flow if a TEVAR endoprosthesis covers the innominate artery following innominate-carotid-left subclavian arterial bypass.

Topics: Aged; Alloys; Aorta, Thoracic; Aortic Aneurysm, Thoracic; Aortography; Blood Vessel Prosthesis Implantation; Brachiocephalic Trunk; Computed Tomography Angiography; Endovascular Procedures; Humans; Materials Testing; Prosthesis Design; Regional Blood Flow; Stents; Stress, Mechanical

The primary mechanically related problems of endovascular aneurysm repair are migration and type Ia endoleaks. They occur when there is no effective seal between the proximal end of the stent-graft and the vessel. In this work, we have developed several deployment simulations of parameterized stents using the finite element method (FEM) to investigate the contact stiffness of a nitinol stent in a realistic Thoracic Aortic Aneurysm (TAA). Therefore, we evaluated the following factors associated with these complications: (1) Proximal Attachment Site Length (PASL), (2) stent oversizing value (O%), (3) different friction conditions of the stent/aorta contact, and (4) proximal neck angulation α. The simulation results show that PASL>18 mm is a crucial factor to prevent migration at a neck angle of 60°, and the smoothest contact condition with low friction coefficient (μ=0.05). The increase in O% ranging from 10% to 20% improved the fixation strength. However, O%≥25% at 60° caused eccentric deformation and stent collapse. Higher coefficient of friction μ>0.01 considerably increased the migration risk when PASL=18 mm. No migration was found in an idealized aorta model with a neck angle of 0°, PASL=18 mm and μ=0.05. Our results suggest carefully considering the stent length and oversizing value in this neck morphology to strengthen the contact and prevent migration.

Topics: Alloys; Aortic Aneurysm, Thoracic; Blood Vessel Prosthesis; Computer Simulation; Elasticity; Equipment Failure Analysis; Finite Element Analysis; Friction; Imaging, Three-Dimensional; Models, Cardiovascular; Pressure; Prosthesis Design; Risk Factors; Stents; Stress, Mechanical

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

The aim of this paper was to report our preliminary experience in outcome, safety and mid-term results in the treatment of thoracoabdominal aortic aneurysms (TAAA) with a novel multibranchstentgraft (E-xtra DESIGN ENGINEERING, JOTEC, Germany).. Eight patients (mean age 66 years, 2 female) with TAAA (Crawford type I: 2 cases, type III: 3 cases, type IV: 3 cases), mean aneurysm diameter 61 mm, growth over 5 mm per year were treated. Implantation was performed under general anesthesia and surgical exposition of the common femoral artery. Brachial access was percutaneous in 5/8 patients. Balloon-expandable (Advanta V12) bridging stent-grafts were employed and lined with self-expanding nitinol stents. All patients except type IV TAAA received a spinal drainage catheter.. The device was successfully deployed in 8/8 patients. 29/32 visceral branches were engaged. One stenosed celiac trunk was left untreated without further consequences, two renal arteries which could not be cannulated were revascularized with iliorenal bypass. One patient needed surgical revision of groin hematoma, one patient suffered from permanent protopathic sensory deficit. No renal complications occurred. Since the primary implantation was deliberately kept short and amount of contrast agent was minimised, four patients needed a secondary percutaneous procedure (Palmaz stent implantation for type I endoleak, re-PTA or additional bridging stent-graft implantation for type III endoleak). The assisted primary success rate was 8/8. Mean follow-up was 18 months. Success was stable in 7/8 patients, one patient shows type V endoleak with 5mm sac expansion. No mortality or complication occurred during follow-up.. The JOTEC E-xtra DESIGN ENGINEERING multibranch stent-graft is a promising new candidate for endovascular TAAA treatment with sufficient safety and efficacy. Its short delivery time suggests its use in patients with rapid aneurysm growth or high anxiety.

Topics: Aged; Alloys; Aortic Aneurysm, Thoracic; Aortography; Blood Vessel Prosthesis; Blood Vessel Prosthesis Implantation; Endovascular Procedures; Female; Humans; Male; Middle Aged; Postoperative Complications; Prosthesis Design; Stents; Time Factors; Tomography, X-Ray Computed; Treatment Outcome; Vascular Patency

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

Treatment of endoleaks after thoracic endovascular repair remains challenging, particularly when the proximal landing zone is small and partly includes the origin of the neck vessels. We report a Type Ia endoleak, occurring after thoracic endovascular aneurysm repair, which was successfully treated with a novel uncovered nitinol stent. With this success, we were able to avoid a conventional surgery to treat the endoleak.

Topics: Aged; Alloys; Aortic Aneurysm, Thoracic; Aortography; Blood Vessel Prosthesis Implantation; Endoleak; Endovascular Procedures; Humans; Male; Prosthesis Design; Reoperation; Stents; Tomography, X-Ray Computed; Treatment Outcome

Endovascular treatments are limited in cases of thoracic aortic aneurysms extending up or proximal to the origin of the left subclavian artery (LSCA). In such cases, the LSCA is usually either occluded or revascularised. We report our first experience of four patients who underwent thoracic aneursym treatment with new custom-made grafts with a scallop in situ for the LSCA. The graft is tailor made per case, and a re-enforced scallop is positioned proximally allowing for the stent to be deployed beyond the origin of the LSCA; the origin of the LSCA remains patent, thus negating the need for revascularisation of the head and neck vessels on the left. The stent contains markers for identifying the scallop and are located along the midline to ensure correct alignment. All of the patients who underwent this procedure had technical success with flow through the LSCA both immediately after stent deployment and on follow-up imaging. This new stent has further expanded endovascular treatment options for patients with thoracic aneurysms extending up to and beyond the LSCA, which can play a part in improving outcome and decreasing mortality rates because surgery for revascularization will not be needed.

Topics: Aged; Aged, 80 and over; Alloys; Angioplasty; Aorta, Thoracic; Aortic Aneurysm, Thoracic; Aortography; Blood Vessel Prosthesis; Blood Vessel Prosthesis Implantation; Female; Humans; Image Processing, Computer-Assisted; Imaging, Three-Dimensional; Incidental Findings; Male; Middle Aged; Prosthesis Design; Prosthesis Fitting; Stents; Subclavian Artery; Tomography, X-Ray Computed

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

To review an experience with the Amplatzer vascular plug (AVP) for prevention of type II endoleaks during endovascular aneurysm repair (EVAR) of thoracic and thoracoabdominal aneurysms.. Retrospective review was undertaken of 14 patients undergoing transcatheter occlusion of the left subclavian (n = 12) or celiac artery (n = 2) with the AVP as part of EVAR of thoracic and thoracoabdominal aneurysms at a single institution. Procedural criteria evaluated were success at target vessel occlusion, the number of AVPs used, use of adjunctive embolization devices, and embolization-related ischemic end-organ events. Follow-up imaging criteria included evaluation of persistent target vessel occlusion, evidence of device migration, and the presence and characterization of endoleak secondary to AVP failure.. Complete target vessel occlusion was documented for all cases. In six cases, more than one AVP was placed, with an average of 1.5 devices per patient. In two cases, adjunctive coils were placed. Computed tomographic or magnetic resonance angiography follow-up was available for all patients (mean follow-up, 419 days; range 28-930 d). No case showed evidence of device migration or type II endoleak resulting from AVP failure. There was a single instance of left subclavian artery recanalization without type II endoleak. There were no embolization-related ischemic end-organ events.. Transcatheter arterial occlusion of the subclavian and celiac arteries with the AVP is a valuable adjunct to endografting in cases in which side branch embolization is necessary to extend the landing zone.

Topics: Adult; Aged; Aged, 80 and over; Alloys; Aortic Aneurysm, Thoracic; Blood Vessel Prosthesis; Celiac Artery; Device Removal; Female; Humans; Middle Aged; Postoperative Hemorrhage; Subclavian Artery; Treatment Outcome

This brief report describes an unusual hybrid approach complication of aortic arch disease. An acute stent kinking in the first post-operative day promoted ventricular fibrillation and death. Adequate oversizing was achieved and intraoperative angiogram showed no proximal or distal leaks. Unfavorable outcomes are highly under-reported and describing complications are a key instrument to improve this technique.

Topics: Alloys; Anastomosis, Surgical; Aortic Aneurysm, Thoracic; Blood Vessel Prosthesis; Blood Vessel Prosthesis Implantation; Fatal Outcome; Foreign-Body Migration; Humans; Male; Middle Aged; Polyethylene Terephthalates; Prosthesis Design; Prosthesis Failure; Stents; Sternum; Time Factors; Tomography, X-Ray Computed; Treatment Outcome; Ventricular Fibrillation

Topics: Alloys; Aorta, Thoracic; Aortic Aneurysm, Thoracic; Blood Vessel Prosthesis Implantation; Humans; Stents; Tomography, X-Ray Computed

To report the use of commercially available stents and a stent-graft in coaxial orientation to extend the proximal limits of endografting within the aortic arch.. A 70-year-old man was found to have an asymptomatic 7-cm saccular aortic arch aneurysm, extending distally from the origin of the left carotid artery and involving the left subclavian artery; there was only 11 mm between the innominate artery orifice and the aneurysm. The patient was deemed to be high risk for open surgical repair due to a history of 2 prior sternotomies and the requirement for hypothermic circulatory arrest. A "double-barrel" stent-graft strategy combining retrograde placement of an innominate stent with thoracic stent-graft implantation into zone 0 was successfully executed. The patient has continued to fare well after 10 months on close follow-up.. The "double-barrel" stent technique may extend the limits of thoracic endografting by preserving the aortic arch branches while avoiding the need for sternotomy. Using this technique, proximal fixation can be obtained well into the ascending aorta using commercially available devices.

Topics: Aged; Alloys; Aorta, Thoracic; Aortic Aneurysm, Thoracic; Blood Vessel Prosthesis Implantation; Humans; Male; Stents; Tomography, X-Ray Computed; Treatment Outcome

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

To describe a technique to facilitate antegrade thoracic endograft deployment using a hybrid elephant trunk operation under hypothermic circulatory arrest.. When using a nitinol-based endograft in a hybrid endovascular aortic arch repair performed in a hypothermic patient, the endograft does not expand fully when the body temperature is typically maintained below 20 degrees C. Immersing the nitinol-based thoracic endograft in a sterile hot saline bath (48 degrees C) for 1 to 2 minutes prior to deployment warms the stent-graft to a physiological temperature of 38 degrees C, which it maintains for several minutes while being deployed.. Although the described technique represents an off-label approach to the use of a TAG device, we believe warming a nitinol-based endograft may potentially improve the technical success of this hybrid operation when the patient is under hypothermic circulatory arrest.

Topics: Alloys; Aortic Aneurysm, Thoracic; Blood Vessel Prosthesis; Blood Vessel Prosthesis Implantation; Cardiopulmonary Bypass; Circulatory Arrest, Deep Hypothermia Induced; Hot Temperature; Humans; Polytetrafluoroethylene; Prosthesis Design; Sodium Chloride; Stents

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

To plan stent-grafting for thoracic aortic aneurysm with complicated morphology, we created a virtual stent-grafting program [Semi Automatic Virtual Stent (SAVS) designer] using three-dimensional CT data. The usefulness of the SAVS designer was evaluated by measurement of transformed anatomical and straight stents. Curved model images (source, multi-planer reconstruction and volume rendering) were created, and a hollow virtual stent was produced by the SAVS designer. A straight Nitinol stent was transformed to match the curved configuration of the virtual stent. The accuracy of the anatomical stent was evaluated by experimental strain phantom studies in comparison with the straight stent. Mean separation length was 0 mm in the anatomical stent [22 mm outer diameter (OD)] and 5 mm in the straight stent (22 mm OD). The straight stent strain voltage was four times that of the anatomical stent at the stent end. The anatomical stent is useful because it fits the curved structure of the aorta and reduces the strain force compared to the straight stent. The SAVS designer can help to design and produce the anatomical stent.

Topics: Alloys; Aortic Aneurysm, Thoracic; Blood Vessel Prosthesis Implantation; Equipment Design; Humans; Imaging, Three-Dimensional; In Vitro Techniques; Software; Stents; Tomography, X-Ray Computed; User-Computer Interface

To assess the technical feasibility and efficacy of distal embolus protection with an intra-aortic filter during stent-graft repair in a patient diagnosed with a shaggy aorta.. In a 75-year-old man with a severely atherosclerotic thoracic aortic aneurysm, stent-graft repair was combined with transposition of the arch branches to the ascending aorta under thoracotomy. A filtration-type embolus protection device with a nitinol basket and polyester fabric was introduced through a 12-F sheath and opened in the supraceliac aorta during the stent-graft procedure; it was safely pulled back into the sheath after the stent-grafts were implanted. The stent-graft repair was successful, and abundant atheromatous debris was captured in the filter. Neither procedure-related embolic events nor neurological deficits were observed.. Use of the intra-aortic filter device to prevent distal embolism during thoracic stent-graft repairs may be feasible and efficacious in severely atherosclerotic patients.

Topics: Aged; Alloys; Aortic Aneurysm, Thoracic; Atherosclerosis; Blood Vessel Prosthesis; Blood Vessel Prosthesis Implantation; Contrast Media; Embolism; Feasibility Studies; Humans; Male; Prosthesis Design; Stents; Tomography, X-Ray Computed; 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 evaluate the clinical efficacy of a curved nitinol stent-graft for repair of thoracic aortic aneurysms.. The Matsui-Kitamura stent-graft (MKSG), composed of a self-expanding nitinol stent and polyester fabric, was shaped to match the aortic curvature of 11 patients (6 men; mean age 72.6 years, range 33-90) with 6 true and 5 false aneurysms of the distal arch or proximal descending aorta. The delivery system was an 18 or 20-F J-shaped sheath combined with a preloader-type introducer. The original mean proximal neck length was 16.4 mm, but 4 patients received an axilloaxillary bypass to lengthen the neck. Although the mean corrected proximal neck length was 21.9 mm (overall), 5 cases still had proximal necks <15 mm long.. All curved MKSGs were successfully deployed in the correct position and fitted to the curvature of the aortic arch, achieving complete aneurysm exclusion in 8 (73%) cases. The other 3 repairs displayed early endoleaks; 1 received an additional MKSG, but the other 2 are being observed. Thirty-day mortality was 0%. One patient developed transient renal failure requiring hemodialysis; no neurological complications were observed.. Endovascular repair of thoracic aortic aneurysms using curved MKSGs appears to be feasible and clinically effective. A tighter fit of the device to the curvature of the aortic arch may exclude distal arch aneurysms despite a short proximal neck.

Topics: Adult; Aged; Aged, 80 and over; Alloys; Aortic Aneurysm, Thoracic; Blood Vessel Prosthesis Implantation; Female; Follow-Up Studies; Humans; Male; Middle Aged; Polyesters; Postoperative Complications; Prosthesis Design; Stents; Treatment Outcome

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

To validate the ease of deployment and in vivo healing performance of a nitinol-polyester self-expanding stent-graft using a canine thoracic aortic aneurysm model.. Arterial aneurysms were surgically created in 8 dogs by sewing a polyester patch onto the anterior side of the thoracic aorta. The nitinol-polyester self-expandable stent-grafts (Cragg EndoPro System 1) were implanted transluminally via the femoral route and deployed at the site of the thoracic aneurysm. Aneurysm exclusion and endograft patency were assessed by angiography after implantation and before animal sacrifice at scheduled periods ranging from 1 week to 3 months. The explanted specimens were examined with magnetic resonance imaging (MRI) to study the position of the stent-graft with respect to the aneurysmal sac. Histological analysis using light microscopy and scanning electron microscopy was performed to examine the inflammatory response and healing characteristics of the device.. Seven of 8 stent-grafts were implanted successfully; a bend occurred within the aneurysmal sac in 1 dog, which led to continued perfusion of side branches. This endoleak sealed spontaneously within 1 week, and complete exclusion of the aneurysms in all 8 animals continued throughout implantation. At the time of explantation, all devices were structurally intact and well positioned in the aneurysmal sac. At 1 week, the luminal surface displayed a thin layer of thrombotic matrix, which was gradually replaced by a collagenous internal capsule with endothelial-like cell coverage along both ends of the stent-grafts at 2 and 3 months. No exacerbated inflammatory reaction due to either the nitinol wires or the polyester sleeve was observed after 3 months of implantation.. This short-term in vivo study of a nitinol-polyester self-expanding endograft demonstrated the effective exclusion of thoracic aneurysms with a satisfactory healing response and no excessive tissue or inflammatory reactions.

Topics: Alloys; Animals; Aortic Aneurysm, Thoracic; Blood Vessel Prosthesis; Blood Vessel Prosthesis Implantation; Dogs; Magnetic Resonance Imaging; Microscopy, Electron, Scanning; Polyesters; Prosthesis Design; Radiography; Stents

The standard technique for the treatment of descending thoracic aortic aneurysms is elective open surgical repair with graft interposition. This standard approach, although steadily improving, is associated with high morbidity and substantial mortality rates and implies a major surgical procedure with lateral thoracotomy, use of cardiopulmonary bypass, long operation times and a variety of peri- and postoperative complications. This and the success of the first endoluminal treatment of abdominal aortic aneurysms by Parodi et al. prompted the attention to be thrown on the treatment of descending thoracic aortic aneurysms with endoluminal stent-grafts in many large centres. The aim of this new minimally invasive technique is to exclude the aneurysm from blood flow and in consequence to avoid pressure stress on the aneurysmatic aortic wall, by avoiding a large open operation with significant perioperative morbidity. The potentially beneficial effect of this new treatment approach was evaluated in the course of this study.

Topics: Adult; Aged; Aged, 80 and over; Alloys; Angiography; Aortic Aneurysm, Thoracic; Blood Vessel Prosthesis Implantation; Catheterization; Coated Materials, Biocompatible; Female; Humans; Male; Middle Aged; Minimally Invasive Surgical Procedures; Polytetrafluoroethylene; Prosthesis Design; Retrospective Studies; Stents; Tomography, X-Ray Computed

Stent-graft placement was performed in 2 patients with saccular aortic aneurysm. A Dacron-covered nitinol stent-graft was deployed in the thracoabdominal and infrarenal abdominal aorta. These procedures were successfully performed. The aneurysm disappeared on intraoperative angiogram immediately after deployment. Follow-up CT showed thrombosis or disappearance of aortic aneurysm. Distal embolization occurred in one patient, who required resection of the small bowel on the following day and renal dialysis due to renal infarction. Both patients were still alive one and a half years and one year after the procedure, respectively. Stent-graft placement is a feasible alternative to surgery for aortic aneurysm in selected patients.

Topics: Aged; Aged, 80 and over; Alloys; Aortic Aneurysm, Abdominal; Aortic Aneurysm, Thoracic; Blood Vessel Prosthesis; Female; Humans; Polyethylene Terephthalates; Stents

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