ABSTRACT
Subject(s)
Adult , Female , Humans , Aneurysm , Arteries , Carotid Artery, Internal , Embolization, Therapeutic , Follow-Up Studies , Magnetic Resonance Angiography , Parents , Prospective Studies , Recurrence , Retinal Artery , Retreatment , Stents , Stroke, Lacunar , ThromboembolismABSTRACT
Objective@#To evaluate endovascular repair combined with fenestrated stent grafts for the treatment of aortic dissection or aneurysm involving aortic arch.@*Methods@#From Jun 2017 to Dec 2018, 30 patients of complicated aortic arch lesions were treated with endovascular repair combined with fenestrated endografts. 26 male and 4 female, aged(53±16) years. All patients had hypertension. 12 cases were treated via needle based in situ fenestration, another 16 cases using physician modified stent grafts, while 2 cases combining these two methods to achieve optimal fenestration. Patients were followed by receiving CTA for mortality, patency of bridging stents, endoleaks and complications.@*Results@#Operations were performed successfully in all cases. The median follow-up is 8.5 months. There was no aorta-related mortality. 1 patient developed cerebral infarction and 1 had hydropericardium. Type Ⅲ endoleaks were observed in 5 patients, no reintervention. All target vessels were patent during the follow up.@*Conclusion@#Fenestrated stent grafts shows satisfactory short-term outcomes in treating aortic arch lesions.
ABSTRACT
Objective To study the process of stent graft implantation into the aortic dissection model by finite element simulation, calculate the stress distribution at different locations of the aorta after the implantation, and analyze the biomechanical mechanism of new lesions for implantation of stent grafts. Methods Based on the computed tomography angiography (CTA) image data of the aorta, a three-dimensional geometric model of patient-specific aortic dissection was established with image segmentation and reconstruction. The wall thickness and material properties of the aortic dissection of the computational models were set according to the literature data. Stent grafting rings with different geometric parameters were designed in a computer-aided design (CAD) software, and the procedure of stent graft implantation was simulated by a finite element analysis software. Results When the implanted stent graft reached a steady-state, the maximum Von Mises stress of the aorta was markedly related to the position of the stent graft and located at the bare stent or small nickel-titanium alloy ring. In the long-term, this force might cause a new tear to appear at the treated aorta. Conclusions The position of the stent graft had a weak effect on the distribution of the maximum Von Mises stress of the aorta, but there was an obvious effect on the Von Mises stress of the aorta. These research outcomes may provide significant guidance for selecting the position of the stent graft.
ABSTRACT
Objective To analyze the influence from strut numbers on biomechanical properties of Z-shaped stentgrafts,especially on their radial support performance and flexibility,so as to provide theoretical support for the design and clinical selection of Z-shaped stent-grafts.Methods Z-shaped stent-grafts with 5,8,10,12 struts were established by finite element method to simulate the process of compression and bending behavior.Radial displacements were applied on surface of the stent-graft and opposite rotations were applied around the z-axis,until a bending angle of 40° was reached.Then parameters such as stent stress,radial support force,strains in graft,cross-section deflection,bending torque were extracted to evaluate the performance of different stentgrafts.Results Compared with stent-grafts with more strut numbers,5-strut stent-graft showed a better radial support performance with the maximum radial force during compression,and it also generated the smallest 68 N · mm torque and 67.5％ cross-section deflection.The tensile strain in graft of 5-strut stent-graft during the process of bending was relatively smaller.Conclusions The strut number of Z-shaped stent-grafts has a significant influence on biomechanical properties of the stent-grafts.Especially the Z-shaped stent-graft with relatively fewer strut numbers shows an advantage in evaluating radial support performance and flexibility such as the bending torque and the cross-section deflection,and is more suitable to be anchored and fit to the tortuous blood vessel,which will play a positive role in decreasing the complication such as endoleaks and thrombosis.The research findings can guide structure design of Z-shaped stent-grafts and optimal selection for surgery.
ABSTRACT
Objective To analyze the influence from strut numbers on biomechanical properties of Z-shaped stentgrafts,especially on their radial support performance and flexibility,so as to provide theoretical support for the design and clinical selection of Z-shaped stent-grafts.Methods Z-shaped stent-grafts with 5,8,10,12 struts were established by finite element method to simulate the process of compression and bending behavior.Radial displacements were applied on surface of the stent-graft and opposite rotations were applied around the z-axis,until a bending angle of 40° was reached.Then parameters such as stent stress,radial support force,strains in graft,cross-section deflection,bending torque were extracted to evaluate the performance of different stentgrafts.Results Compared with stent-grafts with more strut numbers,5-strut stent-graft showed a better radial support performance with the maximum radial force during compression,and it also generated the smallest 68 N · mm torque and 67.5％ cross-section deflection.The tensile strain in graft of 5-strut stent-graft during the process of bending was relatively smaller.Conclusions The strut number of Z-shaped stent-grafts has a significant influence on biomechanical properties of the stent-grafts.Especially the Z-shaped stent-graft with relatively fewer strut numbers shows an advantage in evaluating radial support performance and flexibility such as the bending torque and the cross-section deflection,and is more suitable to be anchored and fit to the tortuous blood vessel,which will play a positive role in decreasing the complication such as endoleaks and thrombosis.The research findings can guide structure design of Z-shaped stent-grafts and optimal selection for surgery.
ABSTRACT
Objective To analyze the influence from strut numbers on biomechanical properties of Z-shaped stent-grafts, especially on their radial support performance and flexibility, so as to provide theoretical support for the design and clinical selection of Z-shaped stent-grafts. Methods Z-shaped stent-grafts with 5, 8, 10, 12 struts were established by finite element method to simulate the process of compression and bending behavior. Radial displacements were applied on surface of the stent-graft and opposite rotations were applied around the z-axis, until a bending angle of 40°was reached. Then parameters such as stent stress, radial support force, strains in graft, cross-section deflection, bending torque were extracted to evaluate the performance of different stent-grafts. Results Compared with stent-grafts with more strut numbers, 5-strut stent-graft showed a better radial support performance with the maximum radial force during compression, and it also generated the smallest 68 N•mm torque and 67.5% cross-section deflection. The tensile strain in graft of 5-strut stent-graft during the process of bending was relatively smaller. Conclusions The struts number of Z-shaped stent-grafts has a significant influence on biomechanical properties of the stent-grafts. Especially the Z-shaped stent-graft with relatively fewer strut numbers shows an advantage in evaluating radial support performance and flexibility such as the bending torque and the cross-section deflection, and is more suitable to be anchored and fit to the tortuous blood vessel, which will play a positive role in decreasing the complication such as endoleaks and thrombosis. The research findings can guide structure design of Z-shaped stent-grafts and the operation to make an optimal selection.
ABSTRACT
Objective To analyze the influence from strut numbers on biomechanical properties of Z-shaped stentgrafts,especially on their radial support performance and flexibility,so as to provide theoretical support for the design and clinical selection of Z-shaped stent-grafts.Methods Z-shaped stent-grafts with 5,8,10,12 struts were established by finite element method to simulate the process of compression and bending behavior.Radial displacements were applied on surface of the stent-graft and opposite rotations were applied around the z-axis,until a bending angle of 40° was reached.Then parameters such as stent stress,radial support force,strains in graft,cross-section deflection,bending torque were extracted to evaluate the performance of different stentgrafts.Results Compared with stent-grafts with more strut numbers,5-strut stent-graft showed a better radial support performance with the maximum radial force during compression,and it also generated the smallest 68 N · mm torque and 67.5％ cross-section deflection.The tensile strain in graft of 5-strut stent-graft during the process of bending was relatively smaller.Conclusions The strut number of Z-shaped stent-grafts has a significant influence on biomechanical properties of the stent-grafts.Especially the Z-shaped stent-graft with relatively fewer strut numbers shows an advantage in evaluating radial support performance and flexibility such as the bending torque and the cross-section deflection,and is more suitable to be anchored and fit to the tortuous blood vessel,which will play a positive role in decreasing the complication such as endoleaks and thrombosis.The research findings can guide structure design of Z-shaped stent-grafts and optimal selection for surgery.
ABSTRACT
This is to report the technique of reversed iliac leg stent-graft in endovascular treatment for isolated internal iliac artery (IIA) aneurysm, which had significant size discrepancy between the common iliac artery (CIA) and external iliac artery (EIA) in 3 patients from different hospitals. Three patients were a 85- and two 82-year-old men. Treated were right IIA aneurysms, sized 6.5x6.2 cm, 5.0x4.0 cm, and 4.1 cm in longest diameter, respectively. The diameters of the right CIA and right EIA measured 21 mm/11 mm, 15 mm/11 mm, and 20 mm/10 mm, respectively. In all cases, reversed iliac leg stent-grafts were prepared on-site; unsheathed and mounted upside-down manually, and deployed in each right CIA. Post-stent-graft angiograms showed complete exclusion of the aneurysms, except for minimal type 1 endoleak in one case. This technique is a useful treatment option in patients with isolated IIA aneurysm.
Subject(s)
Aged, 80 and over , Humans , Male , Aneurysm , Endoleak , Endovascular Procedures , Iliac Aneurysm , Iliac Artery , LegABSTRACT
Transjugular intrahepatic portosystemic shunt (TIPS) has been developed for two decades in order to treat portal hypertension accompanying with upper gastrointestinal hemorrhage and refractory ascites.TIPS may cause the development of hepatic encephalopathy (HE).TIPS induces portalsystemic shunt and leads to hemodynamics chaos. Hepatic encephalopathy belongs to the complications of the portal hypertension. There are many possible predictors of the post-TIPS HE. The relationship between TIPS and HE was reviewed.
ABSTRACT
Objective To summarize the therapeutic effects and feasibility of endovascular repair for infec-tious aortic aneurysms (IAA). Methods The clinical data of seven cases with IAA treated with endovascular repair between May 2006 and July 2007 were retrospectively analyzed. Results Technical success was achieved in all ca-ses. Complete exclusion of the aneurysms was proved by DSA and no endoleaks appeared. No major complications oc-curred. All patients were followed up for 8 to 22 months with no evidence of aneurysms enlargement, stent-grafts mi-gration,endoleak and infection. Conclusion Endovascular repair of infectious aortic aneurysm is a minimally inva-sire, safe and feasible technique and provides good short-term results.
ABSTRACT
Aortic aneurysms involving major visceral arteries or those with short necks are always contraindications to traditional endovascular aortic repair(EVAR).The advent of the fenestrated endovascular aortic repair(F-EVAR)which could exclude aortic aneurysms while presenving blood flow to major organsthrough visceral branches using fenestrated stent-grafts raises the possibility for the treatment of these aorticaneurysms.To update our knowledge,we reviewed the publications on F-EVAR in recent years.
ABSTRACT
BACKGROUND AND OBJECTIVES: Although the standard management of an abdominal aortic aneurysm (AAA) is surgery, endovascular stent-graft treatment is more attractive for patients with significant co-morbid conditions. We evaluated the immediate and mid-term outcomes for the endovascular treatment of AAA. SUBJECTS AND METHODS: Between November 1996 and August 2004, 59 patients with an AAA (53 males, mean age 68.0+/-9.6 years, 3 cases with ruptured AAA) underwent an endovascular stent-graft repair at our institute. All patients were evaluated by an angiography, taken just after the completion of the procedure and at followed up with computed tomography (CT) at 1, 3, 6 and 12 months, and yearly thereafter. RESULTS: Technical success was achieved in 54 of the 59 patients (91.5%). The periprocedural mortality rate was 3.4% (2 of the 59 patients). A primary endoleak was found in 12 patients (20.3%)(type I; 9 patients, type II; 2 patients, type III; 1 patient), 2 of which required subsequent surgical conversion. Spontaneous resolution of an endoleak was seen in 4 patients (33.3%). The average follow-up period of 57 patients was 27.5 months (range from 72 days to 2581 days). In 8 patients (14.0%), a newly developed secondary endoleak was documented. A total 14 patients (23.7%) died during the follow-up period (rupture; 3, operation-related sepsis; 3, unrelated causes; 3, cardiac arrest; 1, unknown causes; 4). The cumulative survival rates at 30 days and at 1 and 2 years were found to be 93.0, and 85.7 and 76.3%, respectively, using Kaplan-Meier methods. Secondary intervention was required in 12 patients (21.8%), and surgical conversion in 4 (6.8%), with 2 (3.4%) requiring conversion to open surgery immediately after the intervention. In those with technical success, without endoleaks and graft failure, the survival rate during follow-up was higher (97.1%; rate with the exception of unrelated cause of death) than that of all the patients. CONCLUSION: The immediate and mid-term results suggest that the endovascular treatment of an AAA is technically feasible and effective. There was higher mortality and morbidity in primary and newly developed endoleak cases; therefore, proper selection of cases, according to the anatomical and clinical criteria, is essential, with meticulous regular follow-ups being critical for the optimal endovascular treatment of an AAA.
Subject(s)
Humans , Male , Angiography , Aortic Aneurysm, Abdominal , Conversion to Open Surgery , Endoleak , Follow-Up Studies , Heart Arrest , Mortality , Sepsis , Survival Rate , Transplants , Treatment OutcomeABSTRACT
Objective:To explore the selection of the treatment methods for acute aortic dissection.Methods:Thirteen patients with acute aortic dissection were studied and analyzed.Results:Of the 13 patients,2 received pharmacotherapy;6 underwent surgical treatment;2 were treated with inplantation of intravascular stent-grafts;1 experienced no treatment because of the ischemic necrosis of the abdominal organs,and 2 suddenly died of the rupture of aortic dissection in the course of emergent management.Conclusion:The emergent pharmacotherapy is essential to all patients with acute aortic dissection.The emergent surgical treatment of acute aortic dissection is selected mainly according to the Debakey Classification.Patients with Debakey Type Ⅰ and Ⅱaortic dissection should undergo operation as early as possible.The outcome of pharmacotherapy is similar to that of surgical treatment based on suitable indications for Debakey Type Ⅲ aortic dissection.Debakey Type Ⅲ aortic dissection can be treated by the intravascular stent-grafts too.
ABSTRACT
Objective To evaluate diagnostic procedures and clinical outcomes of vascular prosthetic and stent graft infection. Methods Clinical data of 15 cases suffering from vascular graft infection between 1985 and 2005 were retrospectively analyzed. Results The rate of vascular graft infection was 1. 14% among our series of 1316 cases of revascularizations. Vascular graft infection occurred within 4 months after graft implantation in 13 cases (86. 7% ). Graft infection developed after 4 months postoperatively in the other 2 cases ( 13. 3% ). Clinical manifestations included wound infection with vascular graft exposure, inguinal swelling or fistula, fever or sepsis, anastomotic hemorrhage, pulse loss of vascular graft or distal lower extremity and gangrene of distal lower extremity. Surgical treatment included en bloc removal of the infected graft and surrounding infected tissue, drainage and local irrigation with antibiotic solution, graft en bloc removal and primary amputation; Graft en bloc removal, drainage and revascularization with a saphenous vein or a new prosthetic graft; Aggressive debridement and local irrigation with antibiotic solution. Four patients died and the others recovered successfully. Conclusion The infection of a vascular graft is a rare complication in vascular surgery. Early diagnosis and aggressive surgical management can improve its prognosis.