Central nervous injury risk factors after endovascular repair of a thoracic aortic aneurysm with type B aortic dissection

Aortic dissection is the deadliest disease of the cardiovascular system.Type B aortic dissection accounts for 30%-60%of aortic dissections and is mainly treated by endovascular repair of thoracic endovascular aneurysm repair(TEVAR).However,patients are prone to various complications after surgery,with central nervous system injury being the most common,which seriously affects their prognosis and increases the risk of disability and death.Therefore,exploring the risk factors of central nervous system injury after TEVAR can provide a basis for its prevention and control.AIM To investigate the risk factors for central nervous system injury after the repair of a thoracic endovascular aneurysm with type B aortic dissection.METHODS We enrolled 306 patients with type B aortic dissection who underwent TEVAR at our hospital between December 2019 and October 2022.The patients were categorized into injury(n=159)and non-injury(n=147)groups based on central nervous system injury following surgery.The risk factors for central nervous system injury after TEVAR for type B aortic dissection were screened by comparing the two groups.Multivariate logistic regression analysis was performed.RESULTS The Association between age,history of hypertension,blood pH value,surgery,mechanical ventilation,intensive care unit stay,postoperative recovery times on the first day after surgery,and arterial partial pressure of oxygen on the first day after surgery differed substantially(P<0.05).Multivariate logistic regression analysis indicated that age,surgery time,history of hypertension,duration of mechanical ventilation,and intensive care unit stay were independent risk factors for central nervous system injury after TEVAR of type B aortic dissection(P<0.05).CONCLUSION For high-risk patients with central nervous system injury after TEVAR of type B aortic dissection,early intervention measures should be implemented to lower the risk of neurological discomfort following surgery in high-risk patients with central nervous system injury after TEVAR for type B aortic dissection.

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.

A computational fluid study on hemodynamics in visceral arteries in a complicated type B aortic dissection after thoracic endovascular repair

Objective:To report a numerical research on the effect of a renal artery arising from false lumen(FL)on the treatment outcome of thoracic endovascular repair(TEVAR)for complicated type B aortic dissection(TBAD).Methods:The original patient-specific model with the right renal artery(RRA)partially supplied by the FL(TFM)was reconstructed from its postoperative computed tomography images.Two additional models were reconstructed by artificially modifying the RRA either fully arising from the FL(CFM)or true lumen(CTM).Computational fluid dynamics(CFD)simulations were performed.Results:First,for all the models,the flow splits to all the visceral arteries were much less than those of a healthy aorta.Second,the flow split to RRA in the CFM and in CTM was the least and largest respectively.Third,in TFM,the pressure gradient between the true lumen(TL)and FL was negative at the proximal FL and the entire FL was full of active blood flow.In the contrast,in CTM and CFM,the pressure differences between the two lumens remained positive and little flow was present in FL.Finally,both TL and proximal FL of this particular patient expanded and the diameters of all visceral arteries decreased at one-year follow-up.Conclusions:Compared to a healthy aorta,a renal artery arising from FL following TEVAR would result in severe visceral ischemia including RA and superior mesenteric artery(SMA).In addition,our numerical simulation of the postoperative hemodynamics of this particular patient perfectly matched with its TL remodeling,FL expansion and contraction of the visceral arteries at one-year follow-up,and a patient-specific CFD simulation may be adopted to obtain information on visceral perfusion after endovascular repair for TBAD patients.

Relationship between acute kidney injury before thoracic endovascular aneurysm repair and in-hospital outcomes in patients with type B acute aortic dissection

Objective Acute kidney injury （AKI） frequently occurs after catheter-based interventional procedures and increases mortality. However, the implications of AKI before thoracic endovascular aneurysm repair （TEVAR） of type B acute aortic dissection （AAD） remain unclear. This study evaluated the incidence, predictors, and in-hospital outcomes of AKI before TEVAR in patients with type B AAD. Methods Between 2009 and 2013, 76 patients were retrospectively evaluated who received TEVAR for type B AAD within 36 h from symptom onset. The patients were classified into no-AKI vs. AKI groups, and the severity of AKI was further staged according to kidney disease： im- proving global outcomes criteria before TEVAR. Results The incidence of preoperative AKI was 36.8%. In-hospital complications was significantly higher in patients with preoperative AKI compared with no-AKI （50.0% vs. 4.2%, respectively; P 〈 0.001）, including acute renal failure （21.4% vs. O, respectively; P 〈 0.001）, and they increased with severity of AKI （P 〈 0.001）. The maximum levels of body tem- perature and white blood cell count were significantly related to maximum serum creatinine level before TEVAR. Multivariate analysis showed that systolic blood pressure on admission （OR： 1.023; 95% CI： 1.003-1.044; P ： 0.0238） and bilateral renal artery involvement （OR： 19.076; 95% CI： 1.914 190.164; P = 0.0120） were strong predictors of preoperative AKI. Conclusions Preoperative AKI frequently occurred in patients with type B AAD, and correlated with higher in-hospital complications and enhanced inflammatory reaction. Systolic blood pressure on admission and bilateral renal artery involvement were major risk factors for AKI before TEVAR.

Endovascular repair of thoracic aortic dissection associated with right-sided aortic arch：report of four cases

Aortic dissection involving a right-sided aortic arch（RAA）is extremely rare with an incidence in adults of 0.04%to 0.1%^（[1]）.Thoracic aortic dissection associated with RAA is even a more uncommon and life-threatening condition.For complicated aortic dissection,conventional open surgical repair is considered a standard therapy^（[2]）.However,

A pilot study of aortic hemodynamics before and after thoracic endovascular repair with a double-branched endograft

Branched endografts have been developed to treat complex pathology in the aortic arch and ascending aorta.This study aims to evaluate the haemodynamic performance of a double-branched thoracic endograft by detailed comparison of flow patterns and wall shear stress in the aorta and supra-aortic branches before and after stentgraft implantation.Pre-and post-intervention CT images were acquired from two patients who underwent thoracic endovascular aortic repair(TEVAR)with a double-branched endograft for thoracic aortic aneurysms.These images were used to reconstruct patient-specific models,which were analysed using computational fluid dynamics employing physiologically realistic boundary conditions.Our results showed that there was sufficient blood perfusion through the arch branches.The presence of inner tunnels caused flow derangement and asymmetric wall shear stress in the ascending aorta,where shear range index was up to 6 times higher than in the preintervention model.Wall shear stress in the aortic arch increased considerably after intervention as a result of accelerated flow.The maximum flow-induced displacement forces on the branched endografts were around 22 N for both patients,which was below the threshold for device migration.Results from this pilot study demonstrated that aortic flow patterns were significantly altered by the branched endograft which caused increased spatial variation of wall shear stress in the ascending aorta and the arch.Although no obvious adverse hemodynamic features were found immediately after intervention for the cases we analysed,follow-up studies will be needed to assess durability of the device.

Thoracic Endovascular Aortic Repair for Cardiopulmonary Arrest Due to Aortic Dissection

Background and Aim: Reports on recovery from Stanford type A aortic dissection (TAAD) leading to cardiopulmonary arrest (CPA) are few. In retrograde TAAD (r-TAAD) cases, some authors reported the efficacy of thoracic endovascular aortic repair (TEVAR). However, only a few reports chose TEVAR for the treatment of r-TAAD resulting in cardiac arrest before hospital arrival. We report a case of r-TAAD presenting with cardiac arrest before hospital arrival not indicated for surgery but TEVAR as treatment. Case: A 65-year-old woman with a history of Marfan syndrome presented to the emergency department after a CPA. Sequential return of spontaneous circulation was achieved 27 min after CPA. Contrast-enhanced computed tomography showed retrograde r-TAAD with an entry tear to the false lumen in the thoracic descending aorta. Therefore, thoracic endovascular aortic repair (TEVAR) was performed with r-TAAD. Afterward, the clinical course was stabilized. This patient suggests that TEVAR is an effective option for the treatment of patients with hemodynamically unstable r-TAAD, even after CPA. Conclusion: TEVAR can lead to a successful recovery from cardiac arrest due to r-TAAD.

Thoracic endovascular aortic repair of chronic type B aortic dissection in 84 patients

Objective The optimal treatment for chronic type B dissection remains controversial. The purpose of this study was to report early and mid-term results of thoracic endovascular aortic repair (TEVAR) of chronic type B aortic dissection. Methods From June 2001 to September 2007, 84 patients with chronic type B aortic

Antegrade in situ laser fenestration of aortic stent graft during endovascular aortic repair:A case report

BACKGROUND The endovascular repair of juxtarenal abdominal aortic aneurysms(JAAA)usually requires combination treatment with various stent graft modifications to preserve side branch patency.As a feasible technique,according to the situation,antegrade in situ laser fenestration still needs to be improved.CASE SUMMARY This report describes a case that was successfully treated with endovascular repair facilitated by antegrade in situ laser fenestration while maintaining renal arterial flow.Laser fenestration was performed using a steerable sheath positioned in the stent graft lumen in front of the renal artery ostium.With the bare stent region unreleased,renal artery perfusion could be maintained and accurate positioning could be achieved by angiography in real time.CONCLUSION This study suggests the feasibility and short-term safety of this novel antegrade in situ laser fenestration technique for select JAAA patients.

Direct visualization of postoperative aortobronchial fistula on computed tomography

BACKGROUND Postoperative aortobronchial fistula(ABF)is a rare complication that can occur in 0.3%-5.0%of patients over an extended period of time after thoracic aortic surgery.Direct visualization of the fistula via imaging is rare.AIM To investigate the relationship between computed tomography(CT)findings and the clinical signs/symptoms of ABF after thoracic aortic surgery.METHODS Six patients(mean age 71 years,including 4 men and 2 women)with suspected ABF on CT(air around the graft)at our hospital were included in this retrospective study between January 2004 and September 2022.Chest CT findings included direct confirmation of ABF,peri-graft fluid,ring enhancement,dirty fat sign,atelectasis,pulmonary hemorrhage,and bronchodilation,and the clinical course were retrospectively reviewed.The proportion of each type of CT finding was calculated.RESULTS ABF detection after surgery was found to have a mean and median of 14 and 13 years,respectively.Initial signs and symptoms were asymptomatic in 4 patients,bloody sputum was found in 1 patient,and fever was present in 1 patient.The complications of ABF included graft infection in 2 patients and graft infection with hemoptysis in 2 patients.Of the 6 patients,3 survived,2 died,and 1 was lost to follow-up.The locations of the ABFs were as follows:1 in the ascending aorta;1 in the aortic arch;2 in the aortic arch leading to the descending aorta;and 2 in the descending aorta.ABFs were directly confirmed by CT in 4/6(67%)patients.Peri-graft dirty fat(4/6,67%)and peri-graft ring enhancement(3/6,50%)were associated with graft infection,endoleaks and pseudoaneurysms were associated with hemoptysis(2/6,33%).CONCLUSION Asymptomatic ABF after thoracic aortic surgery can be confirmed on chest CT.CT is useful for the diagnosis of ABF and its complications.

Proximal true lumen collapse in a chronic type B aortic dissection patient:A case report

BACKGROUND In the context of aortic dissection,increasing pressure within the newly formed false lumen can result in the progressive compression of the true aortic channel.However,true lumen collapse in chronic type B aortic dissection(cTBAD)patients is rare,with few clinical or experimental studies to date having explored the causes of such collapse.CASE SUMMARY In the present report,we describe a rare case of true-lumen collapse in an 83-yearold patient diagnosed with cTBAD,and we discuss potential therapeutic interventions for such cases.Following thoracic endovascular aortic repair(TEVAR),computed tomography angiography revealed satisfactory stent-graft positioning,no endoleakage,true lumen enlargement,thrombus formation in the false lumen,and slight enlargement of the true lumen distal to the stent-graft.Computational hemodynamic analyses indicated that the wall shear stress and pressure within the false lumen were significantly reduced following TEVAR.CONCLUSION TEVAR treatment of cTBAD patients suffering from proximal true lumen collapse can facilitate some degree of effective remodeling.

Short-term results in canines of novel stent-graft design for chimney technique in TEVAR

Introduction:Parallel stent-stent grafting is a major endovascular technique used to preserve the supra-aortic branches during thoracic endovascular aortic repair(TEVAR)of aortic pathologies involving the aortic arch.The short-and mid-term results of this technique are satisfactory;however,endoleak remains a major concern.Thus,here we designed a new chimney stent-graft to decrease the endoleak rate.Aim:To testify the feasibility and safety of the new chimney stent-graft system in a canine model.Material and methods:Six Labrador retrievers were used.Pre-operative data were collected and all operations were performed under general anesthesia.The main and chimney stent-grafts were implanted through the abdominal aorta and left subclavian artery approaches,respectively.Completion digital subtraction angiography(DSA)was performed to confirm the immediate outcomes.All dogs were fed separately for 6 months and sacrificed after aortic angiography.The thoracic aorta and the main and chimney stent-grafts were harvested for histopathologic examination.Results:No complications were found in follow-up DSA.All branch arteries were patent.In?ammatory responses were observed around the stent-grafts in 3 experimental animals,and slight hyperplasia was observed in the surrounding tissues compared with the normal vessels.There was no mural thrombus in the stent,endothelial cells were noted on the inner surface of the stent,and thrombus was formed in the outer skirt and gutter area.The histopathologic examinations revealed similar results to those of gross necropsy observations.Conclusions:This study demonstrated the feasibility and safety of the Longuette stent-graft and the first to report a revised stent-graft specific for chimney technique.

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]

Analysis of imaging characteristics of blunt traumatic aortic dissection: an 8-year experience

BACKGROUND:Traumatic aortic dissection(TAD)has a low incidence but extremely high mortality.It always presents atypical clinical manifestations that are easily missed or misdiagnosed.This study mainly aims to describe the imaging characteristics and management of TAD patients.METHODS:A retrospective analysis of 27 blunt TAD patients was performed between 2013 and 2020.Demographic features,imaging characteristics,and management were analyzed.RESULTS:Twenty-seven patients with type B aortic dissection(age 56.04±16.07 years,20 men)were included.Aortic intimal tears were mostly initiated from the aortic isthmus.The sizes of the proximal intimal tears in the greater curvature were larger than those in the lesser curvature(1.78±0.56 cm vs.1.24±0.52 cm,P=0.031).Compared with those in the control group,the maximum diameters of the aortic arch,thoracic aorta,and abdominal aorta in the TAD patients were all significantly widened(all P<0.050).Multivariate logistic regression analysis showed that the maximum diameter of the thoracic aorta was an independent risk factor for TAD,with a predictive value with an area under the receiver operating characteristic curve(AUC)of 0.673.Finally,26 patients successfully underwent delayed thoracic endovascular aortic repair(TEVAR),and the remaining one patient was treated conservatively.No progression of aortic dissection or death occurred during the six-month follow-up period.CONCLUSIONS:In blunt trauma,the aortic isthmus is the most common site of proximal intimal tears.An accurate diagnosis of TAD requires an overall consideration of medical history and imaging characteristics.Delayed TEVAR might be an eff ective therapeutic option for TAD.

Successful management of life-threatening aortoesophageal fistula: A case report and review of the literature

BACKGROUND Aortoesophageal fistula(AEF)is a rare but life-threatening cause of upper gastrointestinal bleeding.Only a handful of cases of successful management of AEF caused by esophageal cancer have been reported.The purpose of this study is to report a case of AEF managed by endovascular aortic repair and review the relevant literature.CASE SUMMARY A 66-year-old man with upper gastroenterology bleeding presented at the Emergency Department of our hospital complaining of chest pain,fever and hematemesis for 6 h.He had vomited 400 mL of bright-red blood and experienced severe chest pain 6 h prior.He had a past medical history of advanced esophageal cancer.He received chemoradiotherapy but stopped 8 mo prior because of intolerance.A chest contrast computed tomographic scan revealed communication between the esophagus and the descending aorta as well as a descending aortic pseudoaneurysm.According to the symptoms and imaging findings,AEF was our primary consideration.The patient underwent aortic angiography,which indicated AEF and descending aortic pseudoaneurysm.Emergency percutaneous thoracic endovascular aortic repair(TEVAR)of the descending aorta was performed,and bleeding was controlled after TEVAR.He received antibiotics and was discharged after treatment.However,he died 2 mo after the TEVAR due to cancer progression.CONCLUSION Although AEF is a lethal condition,timely diagnosis and TEVAR may successfully control bleeding.

Application of the multi-planar reconstruction in endovascular treatment of type B aortic dissection

Background Although Multi-planar reconstruction （MPR） has been considered a diagnostic imaging technique that observes more perspectives for diseases,few people have applied it surgically.In fact,MPR is also very useful to clinical operation,especially for patients with type B aortic dissection.It helps the surgeon to locate accurately with more information about aortic dissection,so that the safety and effectiveness of operation can be improved.This study examined the application of the MPR in intraoperative DSA imaging for precise positioning by accurately obtaining a crosssection,a spin angle of the coronal plane,and a tilt angle of the sagittal plane in treatment of type B aortic dissection.Methods The conventional and the MPR approaches were compared on positioning the aortic arch for surgery.A group of 40 patients （group A） and another group of 42 patients （group B） was sampled.About the comparison of baseline characteristics,a fourfold table X2 test was conducted on gender,and two independent samples t-test was applied to age between group A and group B.Spin as well as tilt angles for group A were obtained from the patients using both approaches,and their effectiveness was compared with pair t-tests; The MPR data guided stent-grafting in this group.Stent graft placement of group B was based on the conventional approach.Percentages of proximal distributed markers as well as incidences of complications were collected from both groups after stent graft placement.They were also compared with a fourfold table X2 test.Results Gender difference was not found between group A and group B （X2=0.80,P ＞0.05）,and age difference was not statistically significant （F=2.55,homogeneity of variance,t=-1.46,P ＞0.05）.A significant difference was found between the conventional and the MPR approaches for spin angle （t=9.17） as well as tilt angle （t=-2.07）,P ＜0.05.Percentage of proximal distributed markers （5.0％） of group A was significantly lower than that of group B （42.9％）,X2=15.92,P ＜0.05;and incidence of complications （5.0％） of group A was also significant lower than that of group B （21.4％）,X2=4.76,P ＜0.05.Conclusions Application of the MPR facilitated intraoperative angle adaption and led to satisfactory DSA.It is feasible in endovascular treatment of type B aortic dissection,and can effectively and safely guide surgical operations.

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.