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Abstract Various vascular complications following renal transplantation include renal artery and vein thrombosis, renal artery stenosis, pseudoaneurysm, and iliac artery dissection. Transplant renal artery stenosis (TRAS) is the most common, while iliac artery dissection is the rarest of these various vascular complications. We describe an elderly male, who had both external iliac artery dissection and TRAS at 2 months following renal transplantation. He underwent successful percutaneous endovascular intervention of both complications. The post-intervention course was uneventful, with improvement in graft renal functions and left lower limb perfusion.
Resumo As diversas complicações vasculares possíveis após um transplante renal incluem trombose da veia e artéria renais, estenose da artéria renal, pseudoaneurisma e dissecção da artéria ilíaca. Entre essas diversas complicações, a estenose da artéria renal transplantada é a mais comum, enquanto a dissecção da artéria ilíaca é a mais rara. Relatamos o caso de um homem idoso que desenvolveu tanto dissecção da artéria ilíaca quanto estenose da artéria renal transplantada 2 meses após transplante renal. As intervenções endovasculares percutâneas foram bem-sucedidas em ambas as complicações. O período pós-intervenção cursou sem complicações, com melhora na função renal do enxerto e na perfusão do membro inferior esquerdo.
Subject(s)
Humans , Male , Middle Aged , Renal Artery/pathology , Kidney Transplantation/adverse effects , Angioplasty , Iliac Artery/pathology , Stents , Constriction, Pathologic , Endovascular ProceduresABSTRACT
To solve the problem of stent malapposition of intravascular stents, explore the design method of intravascular body-fitted stent structure and to establish an objective apposition evaluation method, the support and apposition performance of body-fitted stent in the stenotic vessels with different degrees of calcified plaque were simulated and analyzed. The traditional tube-mesh-like stent model was constructed by using computational aided design tool SolidWorks, and based on this model, the body-fitted stent model was designed by means of projection algorithm. Abaqus was used to simulate the crimping-expansion-recoil process of the two stents in the stenotic vessel with incompletely calcified plaque and completely calcified plaque respectively. A comprehensive method for apposition evaluation was proposed considering three aspects such as separation distance, fraction of non-contact area and residual volume. Compared with the traditional stent, the separation distances of the body-fitted stent in the incompletely calcified plaque model and the completely calcified plaque model were decreased by 21.5% and 22.0% respectively, the fractions of non-contact areas were decreased by 11.3% and 11.1% respectively, and the residual volumes were decreased by 93.1% and 92.5% respectively. The body-fitted stent improved the apposition performance and was effective in both incompletely and completely calcified plaque models. The established apposition performance evaluation method of stent considered more geometric factors, and the results were more comprehensive and objective.
Subject(s)
Humans , Constriction, Pathologic/surgery , Plaque, Atherosclerotic , StentsABSTRACT
Objective@#To detect the hemodynamic mechanism of the novel endovascular stent on complicated abdominal aortic aneurysms by Computational Fluid Dynamics(CFD) firstly, and then compare the effect of the novel endovascular stent and the streamliner multilayer flow modulator(SMFM) stent.@*Methods@#All medical images were obtained by computed tomography. A semiautomatic segmentation protocol within Mimics(v17.0; Materialise, Leuven, Belgium) was used to extract the threedimensional aortic aneurysms. The stents was generated numerically and fitted along the aortic aneurysms. The lumen volume represented the fluid domain that was discretised in smaller volumes, which defined a mesh within the ICEM software(Ansys ICEM CFD v15.0). Hemodynamic analysis was performed with software Fluent 16.0.@*Results@#Both kinds of stents can change the pattern of flow distribution. Compared with SMFM, the novel endovascular stent can significantly reduce the flow velocity in aneurysms, the shear force and the pressure on the aneurysms wall.What’s more, the flow velocity of the branch artery was accelerated by the novel endovascular stent.@*Conclusion@#The novel endovascular stent can significantly reduce the flow velocity in aneurysms, the shear force and the pressure on the aneurysms wall, and acceleratethe the flow velocity of the branch artery.
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Aortoesophageal fistula (AEF) is a rare and potentially fatal disease that causes massive gastrointestinal bleeding. Therefore, early diagnosis and treatment are essential to prevent mortality. Controlling the massive bleeding is the most important aspect of treating AEF. The traditional surgical treatment was emergent thoracotomy, but intraoperative or perioperative mortality was high. We report a case of a patient presenting with hematemesis who was successfully treated by a staged treatment, in which bridging thoracic endovascular aortic repair was followed by delayed surgical repair of the esophagus and aorta.
Subject(s)
Humans , Aorta , Early Diagnosis , Esophagus , Fistula , Hematemesis , Hemorrhage , Mortality , ThoracotomyABSTRACT
@#Objective To analyze the near-term clinical efficacy of two different surgical procedures (Sun's procedure and Debranching combined endovascular stent-graft procedure) to cure Stanford type A aortic dissection, and summarize the clinical experience to help better master the indications of the two surgical procedures. Methods We retrospectively analyzed the clinical data of 46 patients with Stanford A aortic dissection in our hospital between September 2014 and September 2017. There were 39 males and 7 females at age of 20–74 (48.67±11.80) years. According to different surgical methods, the patients were divided into a Sun's procedure group (26 patients) and a debranching combined endovascular stent-graft procedure group (20 patients). The clinical effect of the two groups was compared. Results The debranching combined endovascular stent-graft procedure group was significantly superior to the Sun's group in cardiopulmonary bypass (CPB) time, aortic cross clamp(ACC) time, intraoperative urine output, postoperative mechanical ventilation time, postoperative 24 h volumes of drain, CICU time, renal function recovery of postoperative 72 h and total hospital stay(P<0.05). The incidence of transient neurological damage after operation in the debranching combined endovascular stent-graft procedure group was significantly lower than that of the Sun's procedure group(P<0.05). The follow-up time ranged from 3 to 36 months. And the follow-up rate was 90.5%. One patient in the Sun's procedure group died of serious pulmonary infection postoperative 30 days. One patient in the debranching combined endovascular stent-graft group was found to have internal leakage in the early postoperative examination and disappeared after 6 months. Sun's procedure group did not find endoleak. All patients during the follow-up time did not appear brain, coagulation disorders, stroke, paraplegia, upper limb ischemia and other complications. Conclusion For Stanford type A aortic dissection, debranching combined surgery may have the risk of postoperative endoleak, but the overall effect is superior to Sun's operation. Therefore, debranching combined surgery should be preferred for the treatment of this type of dissection.
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The current finite element analysis of vascular stent expansion does not take into account the effect of the stent release pose on the expansion results. In this study, stent and vessel model were established by Pro/E. Five kinds of finite element assembly models were constructed by ABAQUS, including 0 degree without eccentricity model, 3 degree without eccentricity model, 5 degree without eccentricity model, 0 degree axial eccentricity model and 0 degree radial eccentricity model. These models were divided into two groups of experiments for numerical simulation with respect to angle and eccentricity. The mechanical parameters such as foreshortening rate, radial recoil rate and dog boning rate were calculated. The influence of angle and eccentricity on the numerical simulation was obtained by comparative analysis. Calculation results showed that the residual stenosis rates were 38.3%, 38.4%, 38.4%, 35.7% and 38.2% respectively for the 5 models. The results indicate that the pose has less effect on the numerical simulation results so that it can be neglected when the accuracy of the result is not highly required, and the basic model as 0 degree without eccentricity model is feasible for numerical simulation.
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Objective To explore the efficacy and safety of endovascular therapy in the treatment of symptomatic M1 stenosis of middle cerebral artery as well as the causes of perioperative complications.Methods Two hundred fifty-six patients with symptomatic M1 stenosis of middle cerebral artery (＞90％) confirmed by TCD,cerebral CT angiography and DSA was treated by endovascular intervention.The success rate,the changes of stenosis,longterm vascular patency rate,in-stent restenosis rate were analyzed.Results endovascular stent was successfully placed in 251 patients with the M1 part of symptomatic middle cerebral artery stenosis and the successful rate was 98.05％.Fifteen patients had complications (5.86％) which caused neurology deficits and deaths.The degree of vascular stenosis was significantly reduced after stenosis (Before vs After:92.26％±2.11％ vs 15.40％±2.60％).The mean mRS and NIHSS scores was decreased significantly.The average follow-up duration was (21.70±0.80) months,249 patients underwent a second DSA and the mean stenosis was (21.70％±0.80％).Twenty-three patients developed instent restenosis (ISR) and ISR rate was 9.24％.Recurrence ischemic stroke and transient ischemic attacks occurred in 5 patients and recurrence rate was 2.01％.Conclusion Endovascular therapy of symptomatic M1 stenosis of middle cerebral artery is safety and efficacy with low complications.The follow-up results reveal good patency rate and excellent prevention of anterior circulation ischemia.
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A 36-year-old male presented with progressive exertional dyspnea over months. Physical examination showed jugular venous distension, lung crecipitations, femoral bruit and pitting pedal edema. Echocardiogram showed a dilated right ventricle with severe pulmonary hypertension and a non collapsing inferior vena cava (IVC). On right heart catheterization, IVC oxygen saturation was noted at 92% suggesting arterial mixing; a computed tomography of the abdomen showed a fistula between the right common iliac artery to the right common iliac vein at L4 level and a massive IVC; this was linked to trauma from a disectomy done 16 years ago at L4–L5 level. Endovascular sealing with a 16 × 60 mm bifurcated stent graft (S & G Biotech, Seoul, Korea) was performed which led to complete resolution of the patient’s dyspnea. Iatrogenic vascular injury during lumbar disc surgery, although rare, can lead to high output cardiac failure developing over months to years.
Subject(s)
Adult , Humans , Male , Abdomen , Arteriovenous Fistula , Blood Vessel Prosthesis , Cardiac Catheterization , Cardiac Catheters , Dyspnea , Edema , Fistula , Heart Failure , Heart Ventricles , Heart , Hypertension, Pulmonary , Iliac Artery , Iliac Vein , Intervertebral Disc Displacement , Lung , Oxygen , Physical Examination , Seoul , Vascular System Injuries , Vena Cava, InferiorABSTRACT
Thoracic endovascular aortic repair (TEVAR) has emerged as an effective therapy for a variety of thoracic aortic pathologies. However, various types of endoleak remain a major concern, and its treatment is often challenging. We report a case of type I endoleak occurring 19 months after zone II hybrid TEVAR. The endoleak was successfully repaired by the frozen elephant trunk technique, without removal of a previous stent graft, combined with ascending aorta and total arch replacement.
Subject(s)
Aneurysm , Aorta , Blood Vessel Prosthesis , Elephants , Endoleak , PathologyABSTRACT
Objective To summarize the experience in the diagnosis and treatment of symptomatic splanchnic artery dissection. Methods A total of 21 patients with symptomatic splanchnic artery dissection, who were admitted to the Affiliated First Hospital of China Medical University during the period from June 2006 to March 2014, were included in this study. Combined with the literature, the clinical data, including the diagnosis and treatment, were analyzed. Results Contrast-enhanced abdominal CT and CT angiography revealed superior mesenteric artery dissection in 15 cases, celiac artery dissection in 5 cases and splenic artery dissection in one case. Conservative therapy was employed in 5 patients; among them one was complicated with hepatic artery thrombosis. Of the 16 patients who received endovascular stent placement, additional intestinal resection was performed in 2 and transcatheter thrombolysis treatment in other 2. No procedure-related severe complications occurred in perioperative period. All the patients were followed up for 2-74 months (mean of 19.1 months). In patients who received endovascular stent placement, the abdominal pain and the bloody stool were relieved or disappeared, and no abdominal pain recurred. CT angiography showed that in-stent blood flow was fluent, the stent was in good position, and neither stenosis nor thrombosis was observed. One patient with superior mesenteric artery dissection died of stroke three months after the treatment. Conclusion It is very important to make early diagnosis and to adopt early treatment for symptomatic splanchnic artery dissection. CT angiography can confirm the diagnosis in most cases, but attention should be paid to some atypical manifestations. For the treatment of splanchnic artery dissection, endovascular stent placement is mini-invasive, safe and reliable.
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Herein, we present a case of a successful treatment of persistent type 2 endoleaks associated with aneurysmal sac enlargement after endovascular aneurysm repair in an elderly patient. We confirmed the diagnosis by abdominal computed tomography and selective angiography revealing an 11.0-cm aneurysm sac with type 2 endoleaks. An attempt for the endovascular embolization of collateral arteries was unsuccessful due to anatomic variations and their multiple complex communications. Instead, transperitoneal sacotomy and direct suturing on the feeding target vessels was successfully performed without any endograft damage. In conclusion, sacotomy appears to be a feasible therapeutic substitute where endovascular or other techniques have a high risk of failure and lead to unsuccessful results.
Subject(s)
Aged , Humans , Aneurysm , Angiography , Arteries , Diagnosis , Endoleak , Prostheses and ImplantsABSTRACT
Type II chronic dissecting thoracoabdominal aortic aneurysms are a surgically challenging disease. The conventional thoracoabdominal aortic aneurysm repair technique using cardiopulmonary bypass is a high-risk procedure. However, a recently developed endovascular technique may be an alternative treatment for the disease, but faces the obstacle of lesional restriction. This new technique uses a hybrid strategy to overcome the limits of endovascular thoracoabdominal aortic aneurysm repair. Herein, we report on a successful outcome after performing the hybrid visceral debranching procedure.
Subject(s)
Aneurysm , Aortic Aneurysm, Thoracic , Cardiopulmonary Bypass , Endovascular ProceduresABSTRACT
Objective To investigate the mechanical effect of stents with different links on the treatment of vertebral artery stenosis, and provide scientific guidelines for the design of stent structure and clinical procedure of stenting intervention. Methods Models of three kinds of stents with different types of links (namely, L-stent, V-stent and S-stent according to the shape of links) and vertebral artery with stenosis were established by using Pro/Engineering, then the same boundary conditions were exerted on the three models to simulate the stent deployed in the vertebral artery by finite element analysis using ABAQUS. Results Compared with L-stent and V-stent, S-stent had a better compliance, generating smaller stress in the arterial wall, causing relatively weak vascular straightening. Due to smaller stress and axial shortening generated in the stent strut, S-stent made less lesion on the arterial wall. Conclusions The therapeutic effect of S-stent is the best among the three kinds of stents, which could reduce in-stent-restenosis, and has good prospect in clinical application.
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Objective To investigate the hemodynamic effect of stents with different types of links on treating vertebral artery stenosis, and provide scientific guidelines for the design of stent structure and the clinical procedure of stent intervention. Methods Models of vertebral artery with stenosis and three kinds of stents with different types of links (named as L-stent, V-stent and S-stentaccording to the shapes) were constructed by using Pro/Engineering. The expansions of these stents in the stenotic vertebral artery were simulated using ABAQUS, and three finite element models of the stented vertebral artery were then established for fluid flow analysis, and hemodynamic simulation was performed using ANSYS-CFX. Results Compared with V-link and S-link stent, L-link stent had smaller area of low wall shear stress distributions and smaller blood stagnation area. Conclusions With better hemodynamic effect, L-stent can potentially reduce the possibility of in-stent restenosis and provide scientific references for the choice of stent, the design of stent structure and surgical planning of stent intervention.
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@#BACKGROUND: The diagnosis of aortitis is often delayed as symptoms are largely non-specific. We report a case of Staphylococcal thoracic aortitis in a 73-year-old Chinese woman complicated by aortic dissection. METHODS: The patient presented with pyrexia of unknown origin, and a contrast enhanced computed tomography aortogram revealed a large thrombus at the anterior aspect of the ascending aorta with two large ulcerations as a result of a chronic type A aortic dissection. A hemiarch replacement with a 28 mm Gleweave Vascutek graft was performed with resuspension of aortic valve commisures. Aortic thrombus cultures were positive for coagulase negative Staphylococcus aureaus, and histology showed chronic dissection of the aorta. RESULTS: The patient was treated with intravenous cefazolin for a 6-week duration and made good progress. CONCLUSIONS: This case highlights Staphylococcal infective aortitis complicated by dissection presenting as fever of unknown origin. Timely diagnosis is essential as progression to catastrophic rupture may occur.
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Aortoenteric fistula (AEF) developed after treatment for an abdominal aortic aneurysm (AAA) is a rare but usually fatal complication. We report a rare case of AEF bleeding after endovascular stent grafting for AAA which was managed angiographically. An 81-year-old man presented with hematochezia and acute abdominal pain for 1 day ago. Four years ago, an aortic stent was implanted in the infrarenal aorta for AAA. Endoscopies were performed to evaluate the hematochezia. Evidence of gastrointestinal bleeding was observed, but a clear bleeding point was not detected on upper endoscopy and colonoscopy. Contrast-enhanced computed tomography performed subsequently showed that the bleeding point was located in the fourth portion of the duodenum as an AEF caused by an inflammatory process in the stent-graft. Intra-arterial angiography showed a massive contrast leakage into the bowel via a small fistula from around the aortic stent graft site. Embolization was successfully performed by injecting a mixture of glue and lipiodol into the AEF tract. The patient was discharged with no evidence of gastrointestinal bleeding after the embolization.
Subject(s)
Aged, 80 and over , Humans , Male , Angiography , Aortic Aneurysm, Abdominal/therapy , Aortic Diseases/etiology , Embolization, Therapeutic , Endoscopy, Gastrointestinal , Fistula/etiology , Gastrointestinal Hemorrhage/therapy , Stents/adverse effects , Tomography, X-Ray ComputedABSTRACT
Objective To propose and numerically simulate a novel stent with triangular wire cross-section so as to compare the hemodynamic effect of endovascular stents in aneurysm with circular, rectangular and triangular cross section, respectively. Methods Three aneurysm models were constructed by implanting 3 kinds of stents separately, including one with bare circular wire cross-section stent (named CM), and one with bare rectangular wire cross-section stent (named RM), and one with bare triangular cross-section stent (named TM). An unstented aneurysm model was also constructed to serve as the control (named UM). Four models were preformed with numerical simulation of fluid-structure interaction under the same boundary conditions using finite element method. Results Compared with TM and CM, RM showed lower velocity, higher flow resistance and longer turn over time, which demonstrated that the effect of blood flow pattern on three stents was decreased in the order of RM, TM, CM. RM could reduce the magnitude and fluctuation of wall shear stress (WSS) more significantly than that of TM and CM. However, the pressure rise of TM and CM was lower than that of RM. WSS distribution and deformation results indicated the possibility of aneurysm development along the distal wall was higher than that along the proximal wall, and the top of aneurysm was in the highest risk of rupture. Conclusions Three kinds of stents show differences of hemodynamics in aneurysm treatment, which provides significant references for the structural design and optimization of endovascular stent.
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Objective To investigate the influence of different protrusion distance of stent strut into the subclavian artery on local hemodynamics of the vertebral artery (VA) ostium.Methods Five models of the VA were established. Model 1 was without stent implantation, Model 2 to 5 was with stent protruding into the subclavian artery for 0, 1, 2, 3 mm, respectively. Computational fluid dynamics analysis was performed to study the differences of hemodynamics in these models. Results After stent implantation, the wall shear stress and the blood flow velocity at the stent segment in the Model 2 was reduced by 85.33% and 35.36%, respectively. The phenomenon of swirling flow disappeared. For models with different protrusion distance, the maximum difference of wall shear stress of VA was 0.76%, and the maximum difference of blood flow velocity is 0.45%. ConclusionsStent implantation can improve the hemodynamics of vertebral artery ostium stenosis, while the protrusion distance of stent strut has no obvious influence on the blood flow velocity and wall shear stress.
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Objective To summarize the preliminary experience of early anticoagulant therapy after endovascular stent graft exclusion for Stanford B type aortic dissection.Methods From June 2006 to June 2011,75 patients[ 65 males,10 fe males,mean age (59.1±13.5) years,range 22 -81 years ] under went endovascular stent-graft exclusion for Stafford B type aortic dissection in Shanghai Xinhua Hospital.Computed tomography angiography (CTA) was used to evaluate the lesions of aortic dissection before endovascular stent-graft exchusion.The descending thoracic aortic diameters were 22 mm to 42 mm [ mean (30.3±4.0) mm ].The distance from the breakage of dissection to the left vertebral artery(LSA)was longer than 1.5 mm in 29 cases,and shorter than 1.5cmin 46 cases.During the operation,left subclavian artery revascularization was per formed to patient,whose left vertebral artery was advantage and needs to be fully or partially covered From the second day after operation,asprin was given to patint,whose left subclavian artery was fully or partially coverd by endovascular stent-graft(no endoleak and residual distal tear).Early anticoagulant therapy lasted 3 months.The symptoms or signs about nervous system were observed in the early stage of postoperation,and the CTA was examined at postoperative 3 months.Results The operation succeeded in 75 patients.The diameters of aortic stent were 26mm to 46rmm[ mean(34.3±4.0) mm ].Left subclavian ar tery revascularization was carried out for 2 cases of all patients.The left subclavian artery was fully or partially coverd in 58 patients(fully covered in 19 cases,2/3 covered in 15 cases,1/2 covered in 24 cases),and 56 patints(no endoleak and residualdistal tear) were given anticoagulant therapy to prevent vertebral artery thrombosis.2 patients(2.7％)died in the early stage after operation.1 patient died of renal failure,1 patient died of dissection rupture,The duration of hospitalization was 4 to 19 days [ mean (7.9±3.5)days ].No neurological complications occurred in hospital.The follow-up period was 6 to 66 months.1 patient died during the follow-up,1 patient had recurrence of Stanford A type aortic dissection and was cured by ascending aorta and aortic arch replacement,1 patient had recurrence of Stanford B type aortic dissection and was cured by second endovascular stent-graft exclusion.All patients had no neurological complications,such as cerebral infarction and paraplegia.Concluslon Early anticoagulant therapy could safely and effectively prevent the neurological complications (such as cerebral infarction and paraplegia) related to vertebral artery thrombosis for Stanford B type aortic dissection patients whose left subclavian artery was fully or partially coverd by endovascular stent-graft.
ABSTRACT
The blood blister-like aneurysm (BBA) of the internal carotid artery (ICA) is a rare but clinically important cause of subarachnoid hemorrhage (SAH), which accounts for 0.5% of incidences of ruptured intracranial aneurysms. BBA is a thin-walled, broad-based aneurysm that lacks an identifiable neck and is one of the most difficult lesions to treat. In this paper, a case is presented of a 57-year-old woman with SAH. Her cerebral angiography demonstrated a small BBA on the dorsal wall of her right ICA. Endovascular treatment that consisted of a stent-within-a-stent was attempted, but the replacement of the second stent failed, and the aneurysm became bigger. Surgery was performed by clipping the BBA with a Sundt slim-line encircling graft clip. The patient completely recovered with no complications. This treatment may be a salvageable option for BBA, especially when endovascular treatment has failed.