Custom Made Fenestrated Stent Graft Collapse after Thoracic Endovascular Aortic Repair: A Case Report

We present a case of stent graft collapse after performing thoracic endovascular aortic repair with a custom-made fenestrated stent graft. The patient was a 70-year-old woman with an asymptomatic aneurysm of the distal aortic arch, and thoracic endovascular aortic repair was performed. The patient showed a blood pressure difference between the left arm and the right arm on postoperative day (POD) 17 prompting the performance of a chest computed tomography scan which revealed stent graft collapse. She then underwent staged debranching of thoracic endovascular aortic repair. Stent graft collapse is a rare but well-described complication of thoracic endovascular repair. Therefore, patients who undergo such a procedure should be carefully monitored for signs and symptoms, which suggest the possibility of stent collapse.

Short-term efficacy of unibody single-branched stent in the treatment of lesions involving the left subclavian artery:two-year follow-up outcomes

The development of thoracic endovascular aortic repair(TEVAR)technology avoids the risk of patients opening the chest and is widely used in Stanford B-type dissection.[1–3]However,because TEVAR technology has clear requirements for vascular anatomy of the lesion,it limits its application to some patients.In the shortcomings of the proximal anchor zone,coverage of the left subclavian artery(LSA)origin without revascularization during TEVAR appears to have increased risk of stroke,upper extremity ischemia and paraplegia.[4]

Total endovascular repair of an intraoperative stent-graft deployed in the false lumen of Stanford type A aortic dissection: A case report

BACKGROUND A 46-year-old male underwent ascending aortic replacement,total arch replacement,and descending aortic stent implantation for Stanford type A aortic dissection in 2016.However,an intraoperative stent-graft was deployed in the false lumen inadvertently.This caused severe iatrogenic thoracic and abdominal aortic dissection,and the dissection involved many visceral arteries.CASE SUMMARY The patient had pain in the chest and back for 1 mo.A computed tomography scan showed that the patient had secondary thoracic and abdominal aortic dissection.The ascending aortic replacement,total arch replacement,and descending aortic stent implantation for Stanford type A aortic dissection were performed 2 years prior.An intraoperative stent-graft was deployed in the false lumen.Endovascular aneurysm repair was performed to address this intractable situation.An occluder was used to occlude the proximal end of the true lumen,and a covered stent was used to direct blood flow back to the true lumen.A three-dimensional printing technique was used in this operation to guide prefenestration.The computed tomography scan at the 1stmo after surgery showed that the thoracic and abdominal aortic dissection was repaired,with all visceral arteries remaining patent.The patient did not develop renal failure or neurological complications after surgery.CONCLUSION The total endovascular repair for false lumen stent-graft implantation was feasible and minimally invasive.Our procedures provided a new solution for stent-graft deployed in the false lumen,and other departments may be inspired by this case when they need to rescue a disastrous stent implantation.

Angioscopic Observation of an Endoluminal Stent Graft: CT Imaging versus Angioscopic Imaging

We could observe the endoluminal stent graft (SG) following thoracic endovascular aneurysm repair (TEVAR) by a coronary artery angioscope and establish intravascular visualization of SG. The patient was a 70-year-old woman with the distal aortic arch aneurysm and the descending aortic aneurysm, and debranching TEVAR were performed. After 12 months follow up, urgent hospitalization was required for chest pain, and cardiac catheter examination with a coronary artery angioscope was performed. The endoluminal SG was observed. The observation in angioscope which is a video image is better than CT that is a still image, and observation in blood vessel or SG is possible. It may be possible to observe the endoluminal SG, allowing potential investigation of an endoleak, or the covering status of the SG with the native aortic vessel wall, or the state of intimal membrane formation in the endoluminal graft.

Viabahn Stent Graft for Inadvertent Insertion of a Central Venous Catheter in the Subclavian Artery

Subclavian artery (SCA) injuries associated with central venous catheter (CVC) insertion are uncommon yet lethal complications that typically require surgical treatment. This case report presents the case of a 94-year-old man with an iatrogenic right SCA injury resulting from a misplaced CVC. Computed tomography revealed the catheter piercing the right internal jugular vein to enter the right SCA and then reaching the aortic arch. Emergent endovascular treatment was performed, and a 13-mm × 50-mm self-expanding Viabahn stent graft (W.L. Gore & Associates, Flagstaff, AZ, USA) was placed via the right brachial artery. The misplaced catheter was successfully removed under simultaneous postdeployment balloon dilatation. This case highlights the utility of the Viabahn stent graft for iatrogenic right SCA injury caused by a misplaced CVC and presents some insights and tips for a safer procedure.

Evaluation of embedded modular branched stent graft in treating aortic arch aneurysm using imaging-based computational flow analysis

Embedded modular branched stent graft(EMBSG)was a new option for aortic arch aneurysm.However,the therapeutic effect of this innovative stenting technique has not been fully assessed.Computational fluid dynamics and three-dimensional structural analyses were performed on three patients(Patient Ⅰ,Patient Ⅱ and Patient Ⅲ)with aortic arch aneurysm,both before and after EMBSG implantation.Patient-specific alterations from preoperative to postoperative were analyzed via morphological and functional metrics.Patient Ⅰ and Patient Ⅱ showed notable curvature changes and area reduction after intervention procedure.Three patients showed an increase in flow velocity after EMBSG implantation,while the pressure drop from ascending aorta to the aortic arch was remarkable in Patient I and Patient Ⅱ with the value of 7.09mmHg,and 10.95mmHg,respectively.Patient I and Patient Ⅱ also showed elevated time-averaged wall shear stress(TAWSS)in the stenting region,while Patient Ⅲ showed a trivial change in TAWSS after intervention procedure.Three patients showed low relative residence time after EMBSG insertion.The short-term results of EMBSG in treating aortic arch aneurysm were promising.Hemodynamic parameters have the potential to assist in the outcome evaluation and might be used to guide the stent graft design and wise selection,thereby improving the long-term therapeutic effect in managing complex vascular disease.

Management of bleeding from pseudoaneurysms following pancreaticoduodenectomy

AIM:To review the clinical course and the management of pseudoaneurysms post-pancreaticoduodenectomy.METHODS: Medical records of 907 patients who underwent pancreaticoduodenectomies from January 1995 to May 2007 were evaluated retrospectively. The clinical course, management strategy, and outcome of ruptured pseudoaneurysms cases were analyzed.RESULTS: Twenty-seven (3.0%) of 907 cases had post-operative hemorrhage from ruptured pseudoan-eurysms. Pancreatic fistula was evident in 12 (44%) cases. Sentinel bleeding appeared in 21 (77.8%) cases. Of the 27 cases, 11 (41%) cases demonstrated bleeding pseudoaneurysm of the ligated gastroduodenal artery, 8 (30%) of the right, proper, common hepatic artery, 2 (7%) of the right gastric artery, and 4 (15%) of the peripancreatic arteries. The remaining two patients died due to sudden-onset massive hemorrhage and pseudoaneurysm rupture was suspected. Emergent operation was performed on 2 cases directly without angiography. Angiography was attempted in 23 cases. Eighteen (78.2%) cases succeeded to hemostasis; the five failed cases were explored. After embolization of the hepatic artery, five cases developed liver abscesses or infarction and a single case of hepatic failure expired. Gastroduodenal artery embolization with common hepatic artery stent insertion was performed to enhance hepatic artery flow in a single case and was successfully controlled.CONCLUSION: Bleeding pseudoaneurysms are among the most serious and fatal complications following pancreaticoduodenectomy. Diagnostic angiography has been preferred over endoscopy and is rapidly becoming the standard therapeutic treatment for bleeding pseudoaneurysms.

Fatal bleeding due to an aorto-esophageal fistula: A case report and literature review

BACKGROUND Aorto-esophageal fistula is an extremely rare cause of acute upper gastrointestinal bleeding(UGIB).CASE SUMMARY We present a case of an 80-year-old woman with esophageal cancer who was admitted to our department with hemorrhagic shock due to UGIB.During the diagnostic procedure,emergency computed tomography angiography was performed and confirmed aorto-esophageal fistula.Interventional radiologists inserted a stent graft into the aorta,successfully closing the fistula.Unfortunately,the patient later died of heart failure following irreversible hemorrhagic shock.Autopsy confirmed the aorto-esophageal fistula,which formed 1 cm below the distal edge of the stent previously inserted into the esophagus for a malignant stricture.CONCLUSION There are very rare causes of UGIB.Although clinical decisions are made during the diagnostic workup of these patients,we must be aware of the limitations of various therapeutic options,even the most contemporary.

Emergent Technologies for Cardiovascular Surgery

The optimal vascular blood supply throughout the body guarantees the support of normal functions to tissues and organs.Implants are now becoming a seamless extension of the body and shall accompany a higher level of fidelity between the device and the patient.As regenerative medicine is still in its infancy,the ongoing search for new and effective prosthetic alternatives continues to be essential and highly rewarding.Thanks in part to the progress of imaging and the benefits of 3D printing,previously unimagined emergent technologies are at hand.The emerging technologies of the last few decades and the near future will continue to greatly improve both the quality and quantity of patients' lives.They focus on minimally invasive technologies(keyhole surgery) and approaches for deployment of valves,stent-grafts,leadless pacemakers and adaptation of medical devices for destination therapy(assist devices and artificial hearts).In addition,specific blood conduits for the aortic valves together with the aortic arch and the pulmonary valves are considered.These breakthroughs are currently at various stages of development and acceptability.Innovative biomaterials were essential in the development of cardiovascular devices.They were and they still are the essential support for conduction prosthesis,but their place in signal prosthesis is being revisited.Any new development in medical devices has been frequently driven by surgeons and industry.The emergent technologies are introduced by pioneers.The risks and benefits of devices must be continuously reassessed during the lifetime of the implants based upon sound scientific principles of investigation,clinical experience of the users and retrieval programs.

In vitro Stent Graft Fenestration to Preserve All Supra-aortic Branches in the Treatment of a Stanford Type A Aortic Arch Dissection

For aged patients,the treatment of type A aortic dissection （TAAD） with the primary entry tear at the inner curve of the ascending aorta is a great challenge.Conventional surgical repair with cardiopulmonary bypass and deep hypothermic circulatory arrest is associated with high risk ofmortality. Thoracic endovascular aortic repair （TEVAR） with associated techniques to reconstruct all supra-aortic branches is still controversial. Herein,we reported a new endovascular method.

Multilayer stents, a new progress in the endovascular treatment of aneurysms

Objective To review the recent progress of multilayer stents in treating arterial aneurysms and to draw an initial conclusion about its paradigm. Data sources PubMed database and ELSEVIER database were searched with the keywords ＂cardiatis＂ or ＂multilayer stent＂ for relevant articles from January 2008 to September 2012. Relevant websites （provided by Cardiatis） were also involved in the review process. Study selection Well-controlled, relatively large-scale, retrospective studies as well as meaningful individual cases were all selected as materials. Results A total of 23 articles were involved in this review. The newly introduced Cardiatis muttilayer stent aims at creating an active flow-modulating barrier between normal blood flow and aneurismal sac, which can induce thrombosis within aneurismal sac and preserve collateral circulation at the same time. Currently, it has been applied for complicated aneurysms located in different segments of the arterial system. Conclusion This new concept of multilayer uncovered stent offers a promising alterative in the treatment of arterial aneurysms. However, a further larqe-scale clinical and hemodynamic study is reauired to evaluate the Iona-term effects.

Transluminal stent graft placements for the treatment of Standford B type aortic dissection

Management of patients with aortic dissection includes medical and surgical treatments.Because of the high surgical morbidity and mortality rate, transluminal stent graft placement （TSGP） has emerged as a new treatment instead of open surgery for aortic dissection of a descending aortic intimal tear.1 In our institute, we use TSGP to seal the entry site for both acute onset and chronic Standford B type aortic dissections. The implantation technique and outcome of this treatment are discussed.

Management of Acute Lower Extremity Thrombosis Associated with Bilateral Popliteal Aneurysms Using Combined Thrombolytic Therapy and Stent Graft Repair

To the Editor：This is a brief clinical report on different endovascular procedures in the treatment of popliteal artery aneurysms （PAAs）.A 75-year-old man presented at the vascular clinic with progressive left lower limb pain at rest associated with coolness,pain,and paresthesia.His medical history was significant for hypertension and hyperlipidemia.The femoral and popliteal pulsations were only felt in the left limb.Coldness,pallor,paresthesia,delayed capillary refilling,and color changes were noted in the left limb together with rest pain.Duplex ultrasound was performed and an embolization （Rutherford Grade 2b） and bilateral PAAs were found,which on computed tomography angiogram （CTA） measured 62 mm and 82 mm with the maximum diameters in the right and left popliteal artery,respectively.Thrombus was found in both aneurysm sacs [Figure 1 a and b].Thromboembolism from the left PAA could be seen in the distal arteries.Other potentially associated aneurysms were excluded by magnetic resonance angiography.The erythrocyte sedimentation rate and C-reactive protein were moderately elevated,and thrombophilia profile was negative,and history for any orogenital ulcers was negative.

PTFE Electrospun Stent Graft—Preparation,Properties and Its Industrialization Prospect

Stent graft(SG),isolating the diseased vessels from the normal blood circulation and preventing the rupture of the aneurysm wall in minimally invasive surgery,is normally composed of a metallic stent and a cover with a textile structure.In this study,the electrospinning method was used to prepare a new type of cover,and the preparing conditions and the performance of the SG were investigated.The polytetrafluoroethylene(PTFE)and polyethylene oxide(PEO)were blended at the ratios of 99:1,98:2,97:3 and electrospun to form precursor membranes.Then they were dried in a vacuum and sintered at different temperatures under different time periods to obtain PTFE membrane,which was compounded with a stent.Their morphology,mechanical properties,water permeability and biological properties were studied.The results showed that when the membrane was sintered at 380℃ for 10 min,it had the best tensile properties.The integral water permeability of the PTFE electrospun SG was close to 0.The hemolysis rate of the SG was 2.84%,and human umbillical vein endothelial cells(HUVECs)can adhere and proliferate well on the surface of the PTFE membranes.The PTFE electrospun SG had great potential for clinical application and industrialization.

Progress of research on the biomechanics of aorta and stent graft

With improvements in the technology of clinical diagnosis of aortic diseases, more and more cases have been found on such vascular lesions as aortic dissection and abdominal aortic aneurysm, which lead to aortic biomechanical changes. Aortic biomechanics research will become a hot spot in the near future. At the same time, stent grafts （SGs） are widely used in the endovascular treatment of vascular diseases. The biomechanical properties of SGs will also become a focus of research. Understanding the relation between the aorta and SGs will better cater to clinical services by improving the success rate of surgery for aortic diseases and reducing intraoperative and postoperative complications. This article reviews researches on the biomechanics of the aorta and SGs.

Hemodynamic evaluation of different stent graft schemes in aortic arch covered stent implantation

Implantation of the left subclavian artery(LSA)stent graft used in fenestration technique of the thoracic endovascular aortic repair(TEVAR)may interfere with the aortic helical blood flow that is believed to have important protective functions against atherogenesis.The present study investigated four different LSA stent graft implantation schemes for their resulted blood flow patterns in the thoracic aortic with hemodynamic computational simulation methods:the flush branch(FB),the protruding branch(PB),the straight cuff branch(SCB)and the cured cuff branch(CCB).The results showed that the PB scheme could slightly enhance helicity of the swirling flow in the aorta,but the other three schemes had less effect on blood flow helicity.The PB scheme produced lowTAWSS,high-OSI and high-RRT around the LSA root,and the FB scheme had similar TAWSS,OSI and RRT in both value and distribution to those in the aorta without LSA stent graft implantation.The SCB and CCB schemes led to less area of high-OSI and high-RRT values along the walls of the LSA branch arteries.The results also showed that the PB scheme would significantly reduce blood supply to the LSA,on the contrary,the CCB scheme enhanced LSA blood supply and less effect on the total blood supply to the three branches of the thoracic aorta.In summary,all of the four schemes have no significant effect on the aortic swirling flow,however,in the terms of TAWSS,OSI,RRT and blood supply to the LSA,the CCB model might be the best option with less area of low-WSS,high-OSI,high-RRT and well blood supply in the LSA.

Outcome of stented elephant trunk technique for extensive thoracic aortic aneurysms

Extensive aneurysms involving the ascending aorta, aortic arch, and the descending aorta stand as a therapeutic dilemma in simultaneous management of multiple sites of pathology of the aortic arch and the descending thoracic aorta. We systematically reviewed about literatures of stented elephant trunk operation （SET） identified through searches of the electronic databasesEMBASE and Medline, and aimed to summarize studies of patients undergoing SET for extensive aneurysms. Since 1996, Kato Mintroduced a hybrid technique by using stented graft implantation to the descending aorta for treatment of thoracic aortic aneurysm or dissection. It has been describe a good option for extensive thoracic aortic aneurysms and in a fashion similar to the elephant trunk technique.

Endovascular repair： alternative treatment of ruptured abdominal aortic aneurysm

Background As an alternative to open aneurysm repair, endovascular ruptured abdominal aortic aneurysm （rAAA）. The aim of this study was outcomes of EVAR for rAAA. aortic repair （EVAR） has been applied to to evaluate the immediate and long-term Methods From July 1997 to September 2007, 20 men and six women with rAAA （median age, 68 years） were treated with EVAR. Most patients with suspected rAAA underwent emergency computed tomographic angiography （CTA）. The procedure was performed under general or local anesthesia. Endovascular clamping was attempted in hemodynamically unstable patients. Bifurcated endografts and aorto-uni-iliac （AUI） endografts with crossover bypass were used. Patients had CT scan prior to discharge, 3, 6, 12 months after discharge, and annually thereafter. Results Time between diagnosis and EVAR ranged from 1 hour to 5 days. EVAR was performed under general anesthesia in 21 patients, and under local anesthesia in five patients. Endovascular aortic clamping was performed in four patients. There was no conversion to open surgery during EVAR. Stent-graft insertion was successful in all patients. One patient died during EVAR from acute myocardial infarction. Ten patients had systolic blood pressure 〈80 mm Hg. Eleven patients received a blood transfusion. Mean aneurysm size was （47±12） mm. Mean ICU stay was （8±3） days, mean hospital stay （18±6） days, and mean procedure time （120±32） minutes. The 30-day mortality was 23% （6/26 patients）, and major morbidity 35% （9/26 patients）. Early endoleak occurred in 8/26 patients （31%）. The mean follow-up was （18±7） months. No patient demonstrated migration of the stent-graft. Conclusions EVAR is a safe and effective option for treatment of acute rAAA, independent of the patient＇s general condition. Immediate and mid-term outcomes are favorable, but long-term outcome is unknown. Multi-center studies are necessary to establish the role of EVAR for rAAA.

Endovascular Management of Aortic Arch Diseases:Current Status and Future Trends

Treatment of aortic arch(AA)diseases is challenging for surgeons.Conventional open surgery remains the“gold standard”but is associated with significant morbidity and mortality despite improvements in techniques.In the last 2 decades,thoracic endovascular aortic repair(TEVAR)has become the first-line treatment for diseases of the descending aorta,and its indications have expanded gradually.Various strategies have been proposed to preserve supra-aortic branches in TEVAR:hybrid technique,chimney technique,fenestration technique(including custom-made fenestrated or“scalloped”stent grafts,in situ fenestration,and physician-modified fenestration),and branched stent grafts.Though acceptable outcomes of endovascular aortic repair have been documented,the evidence regarding its long-term safety and efficacy is lacking,and concerns remain about the risk of cerebrovascular events,retrograde type-A dissection,endoleaks,and branch occlusion.This review discusses the current status and progress of endovascular repair of the AA,and looks toward future trends.We believe that multidisciplinary collaboration of a“HENDO”team(professionals in hybrid repair,endovascular repair,open surgery,cardiovascular anesthesia,and genetics)is essential for future repair of the AA to provide the optimal treatment.

Optimization of fenestrated technique in application to aortic aneurysms with an attached branch

Background:The fenestrated stent technique has been developed for the treatment of aneurysms with branches.However,the hole size and type,which are the key factors for optimal treatment outcomes,are still controversial in clinical application.Therefore,a hemodynamics investigation in terms of the size and type of the hole was performed with the objective of providing evidence for optimization of this technique.Method:Six cases were modeled for comparison:cases 1 and 2 corresponded to suprarenal aortic aneurysm(SRAA)models with no stent and a multilayer stent(MS),respectively;cases 3–6 represented the SRAA models treated with fenestrated stent grafts(FSGs)including a small-sized hole(SSH,3 mm),middle-sized hole(MSH,6 mm),large-sized hole(LSH,9 mm),and multiple holes(MH,which included the features of both the MS and stent graft,6 mm),respectively.The total stent area in cases 4 and 6 was equal to the cross-section of the branch.Results:As opposed to cases 1 and 2,the pressure on the aneurysmal wall reduced more significantly with FSG intervention(cases 3–6),and the area of low wall shear stress(WSS)on the aneurysmal wall was unexpectedly large in case 5 owing to jet flow deflection.The branch flux increased with the increase of the hole size,and normal blood flow in the branch was only observed in case 5.Interestingly,the weakest jet flow was found in case 5.Conclusion:Our findings indicate that the diameter of the hole should be slightly larger than that of the branch to achieve better aneurysm isolation and preserve branch patency.