Distribution of Air Embolization During TEVAR Depends on Landing Zone: Insights From a Pulsatile Flow Model

2019 ◽  
Vol 26 (4) ◽  
pp. 448-455 ◽  
Author(s):  
Vladimir Makaloski ◽  
Fiona Rohlffs ◽  
Constantin Trepte ◽  
E. Sebastian Debus ◽  
Bent Øhlenschlaeger ◽  
...  

Purpose: To analyze the distribution of air bubbles in the supra-aortic vessels during thoracic stent-graft deployment in zones 2 and 3 in an aortic flow model. Materials and Methods: Ten identical, investigational, tubular, thoracic stent-grafts were deployed in a glass aortic flow model with a type I arch: 5 in zone 2 and 5 in zone 3. A pulsatile pump generated a flow of 5 L/min with systolic and diastolic pressures (±5%) of 105 and 70 mm Hg, respectively. The flow rates (±5%) were 300 mL/min in the subclavian arteries, 220 mL/min in the vertebral arteries, and 400 mL/min in the common carotid arteries (CCAs). The total amounts of air released in each supra-aortic branch and in the aorta were recorded. Results: The mean amounts of air measured were 0.82±0.23 mL in the zone-2 group and 0.94±0.28 mL in the zone-3 group (p=0.49). In the zone-2 group compared with zone 3, the amounts of released air were greater in the right subclavian artery (0.07±0.02 vs 0.02±0.02 mL, p<0.01) and right CCA (0.30±0.8 vs 0.18±07 mL, p=0.04). There were no differences between the groups concerning the mean amounts of air measured in the right vertebral and all left-side supra-aortic branches. The amount of air released in the descending aorta was significantly higher in the zone-3 group vs the zone-2 group (0.48±0.12 vs 0.13±0.08 mL, p<0.01). Small bubbles were observed continuously during deployment, whereas large bubbles appeared more commonly during deployment of the proximal stent-graft end and after proximal release of the stent-graft. Conclusion: Air is released into all supra-aortic branches and the descending aorta during deployment of tubular thoracic stent-grafts in zones 2 and 3 in an aortic flow model. Higher amounts of air were observed in right-side supra-aortic branches during deployment in zone 2, whereas significantly greater amounts of air were observed in the descending aorta during deployment in zone 3.

2018 ◽  
Vol 25 (5) ◽  
pp. 542-546 ◽  
Author(s):  
Yuk Law ◽  
Tilo Kölbel ◽  
Johannes Schirmer ◽  
Shadi Aleed ◽  
John Mogensen ◽  
...  

Propose: To describe a technique for antegrade cannulation and bridging of the supra-aortic branches through a transapical access in the treatment of an arch aneurysm using combined ascending and branched arch stent-grafts. Technique: An 81-year-old man with a past history of open infrarenal aortic repair, emergent endovascular aortic repair for thoracic aortic rupture, and later perivisceral 4-vessel branched endovascular repair of type I thoracoabdominal aneurysm presented for repair of a concomitant 7.5-cm arch aneurysm. Because of a 44-mm ascending aorta, a tapered 50/44-mm ascending stent-graft was delivered through a transapical access to establish an adequate landing zone before implantation of a 46-mm inner branched arch device via a transfemoral route. Innominate and left subclavian arteries were antegradely cannulated and bridged through the existing transapical path. Conclusion: Our case demonstrates the feasibility of transapical access for cannulation of an arch branched device, while introducing the theoretical possibility of completing the entire procedure through a transapical access.


Vascular ◽  
2013 ◽  
Vol 21 (2) ◽  
pp. 92-96 ◽  
Author(s):  
D L H Baird ◽  
K Mani ◽  
T Sabharwal ◽  
P R Taylor ◽  
H A Zayed

Current endovascular treatments for isolated iliac artery aneurysms (IIAAs) include the use of aortoiliac stent grafts with coverage of the distal aorta or stent grafts confined to the iliac artery without active proximal fixation. We report our experience in the use of custom-made Cook Zenith™ iliac limb stent grafts with proximal barb fixation. Patients treated from July 2009 to February 2011 were included. All imaging and patient records were assessed for perioperative and early outcomes. Nine IIAAs (seven patients) were treated. The mean patient age was 80 years (range 58-91 years). The mean aneurysm size was 48 mm (35-80 mm), and the mean length of the proximal landing zone (PLZ) was 29 mm (10-50 mm). The distal landing zone was in the external iliac artery after coil embolization of the internal iliac artery. The Mean diameter of the PLZ was 21 mm (20-24 mm). Technical success was achieved in eight cases. Perioperative complications included reoperation in one patient for groin bleeding and ischemia. On follow-up (mean 12 months, range 1-26), all aneurysms were successfully excluded from the circulation and there was no stent graft migration or thrombosis. Use of custom-made stent grafts with proximal barb fixation in treatment of IIAAs is a feasible option which may reduce the risk of migration when compared with stent grafts with lack of proximal fixation.


Author(s):  
Siamak Mohammadi ◽  
Jean-Pierre Normand ◽  
Pierre Voisine ◽  
François Dagenais

Objective Use of thoracic Stent-graft in patients with connective tissue disorders (CTD) remains limited. We herein report 3 patients with CTD who underwent stent grafting. Methods and Results Case 1; A male Marfan patient was operated for thoraco-abdominal aneurysm. On computed tomography (CT), large false aneurysm at the proximal anastomosis was documented which was excluded with a 30 mm Talent stent-graft with 10–15% oversize. Case 2; A female with Ehlers-Danlos syndrome had undergone resection of descending aortic thoracic aneurysm presented with an enlarging aneurysm distal to the graft. Three Talent stent-grafts (15% oversize) were deployed with balloon dilatation to exclude the aneurysm. The immediate postoperative period was complicated by an extensive intramural hematoma of the descending aorta with hemothorax, managed conservatively. Case 3; A female Marfan patient had undergone Bentall procedure and mitral repair followed with resection of the proximal descending aorta. Three months later a false aneurysm at the distal anastomosis was treated with a 24 mm Valiant stent-graft (30% oversize). Aortic dissection distal to stent was documented on the early postoperative CT. The dissected aneurysm enlarged significantly with a type I distal endoleak during follow-up. Concomitantly, the patient presented a class III dyspnea owing to a severe mitral regurgitation. The patient underwent a successful MVR and stent-graft explantation with replacement of the descending aorta. Conclusion Significant complications supervened when stent-grafts were deployed in native aorta. We thus recommend that deploying a stent-graft in a CTD diseased aorta should be considered a relative contraindication. In cases with prohibitive or high risk surgery, use of a stent-graft with minimal radial force and minimal oversizing without balloon dilatation should be considered.


Author(s):  
Xuelian Gu ◽  
Kai Yu ◽  
Licheng Lu ◽  
Wenjing Tang

Endovascular aneurysm repair (EVAR) techniques have been widely used for the treatment of abdominal aortic aneurysm (AAA). EVAR is associated with lower postoperative morbidity and mortality than traditional surgical procedure to treat AAA [1]. However, during the patient’s follow-up, postoperative complications may occur and secondary interventions are required [2]. Stent-grafts fixation in the vessel affects the success of endovascular aneurysm repair. Researches indicate that insufficient stent-graft radial force is attributed to post-surgery complications, such as prosthesis migration and endoleak type I [3, 4]. Endoleak type I happens when there is not a complete contact between stent graft rings and vessel wall. A great radial force can prevent full obturation in the landing zone. The distal endograft fixation also has a great influence on proximal endograft migration after EVAR [5]. Therefore the radial force of the stent plays a significant role. Single stent-graft ring comprise a series of expandable Z-shaped structural elements (known as “struts”). Currently, there are series of Z-shaped stent-grafts on the market and the struts number ranges from 5 to 12. This work intends to analyze the influence of stent-graft struts number on the radial force. Finite-element analysis (FEA) and experimental method are used.


2019 ◽  
Vol 26 (5) ◽  
pp. 697-703 ◽  
Author(s):  
Suteekhanit Hahtapornsawan ◽  
Konstantinos Lazaridis ◽  
Frank J. Criado ◽  
Giovanni Federico Torsello ◽  
Theodosios Bisdas ◽  
...  

Purpose: To evaluate chimney stent-graft position and morphological changes of the aneurysm sac as visualized by postoperative computed tomography angiography (CTA) over a minimum 24-month follow-up period. Materials and Methods: Twenty-one patients (mean age 75.7±8.6 years; 20 men) with juxtarenal aortic aneurysms who underwent successful chimney endovascular aneurysm repair (ch-EVAR) with the Endurant stent-graft and had 2 postoperative CTAs separated by at least 24 months were included in the study. CTA-based measurements of aortic stent-graft migration, target vessel angle, and chimney angle were compared between the serial scans. Results: During a mean follow-up of 34.9 months (range 24–69.2), the mean migration of the aortic stent-grafts was under 5 mm (2.76±2.4 mm). The average migration distance per year was 1.15 mm. The aneurysm diameter reduced a mean 3.25 mm (p=0.048). The right renal artery angle moved significantly upward 6.72° (p=0.025), while the right renal chimney stent-graft moved significantly downward 7.83° (p=0.042). The left renal artery angle also moved upward 1.87° (p=0.388) and the corresponding chimney moved downward 5.68° (p=0.133). During the study period, no type I/III endoleak or chimney occlusion was observed. Conclusion: Midterm morphometric assessment of ch-EVAR using CTA showed significant aneurysm sac shrinkage and a stable 3-year position of the abdominal devices, with the mean downward migration of the aortic stent-graft being <5 mm in the majority of cases. The chimney grafts seem to be prone to take an oblique rather than parallel configuration during follow-up. However, there was no relevant clinical consequence related to this phenomenon.


2016 ◽  
Vol 24 (1) ◽  
pp. 75-80 ◽  
Author(s):  
Tilo Kölbel ◽  
Christian Detter ◽  
Sebastian W. Carpenter ◽  
Fiona Rohlffs ◽  
Yskert von Kodolitsch ◽  
...  

Purpose: To describe the combined use of a tubular stent-graft for the ascending aorta and an inner-branched arch stent-graft for patients with acute type A aortic dissection. Technique: The technique to deploy these modular, custom-made stent-grafts is demonstrated in 2 patients with acute DeBakey type I aortic dissections and significant comorbidities precluding open surgery. Both emergent procedures were made possible by the availability of suitable devices manufactured for elective repair in other patients. After preliminary carotid-subclavian bypass, a long Lunderquist guidewire was introduced from the right femoral artery to the left ventricle for delivery of the Zenith Ascend and Zenith Branched Arch Endovascular Grafts under inflow occlusion. Bridging stent-grafts were delivered to the innominate and left common carotid arteries to connect to the 2 inner branches; the left subclavian artery was occluded. Both cases were technically successful and resulted in exclusion of the false lumen in the ascending aorta. The operating and fluoroscopy times did not exceed those of comparable elective procedures. The patients were rapidly extubated shortly after the procedure and without serious immediate complications. One patient survived 11 months with a satisfactory repair; the other succumbed to complications of recurrent pneumonia after 23 days. Conclusion: Endovascular treatment of patients with acute type A aortic dissection using a combination of tubular and branched stent-grafts in the ascending aorta is feasible and offers an alternative strategy to open surgery.


2021 ◽  
pp. 7-9
Author(s):  
Seena N ◽  
Lekha K S ◽  
Arivuselvan S

Background: Variations of the Hepatic Portal Vein are encountered during abdominal surgeries. Aim: The present study is an observational study of the extrahepatic part of Portal Vein & its variations on cadavers. Materials & Methods: A total of 50 upper abdomen dissections were carried out to delineate extra-hepatic Portal Vein anatomy. The Results: mean length of Portal Vein was 5.96cm. The mean diameter of Portal Vein was 1.35cm. The most common type of formation of Portal Vein was Type I, found in 64%. The Right Gastric Vein commonly emptied into the trunk of the Portal Vein. The Left Gastric Vein commonly emptied into the trunk of the Portal Vein in 87.18%. The most common type of Portal Vein termination was Extra-Hepatic, found in 76% of 50 dissections. The Bifurcation pattern was the most common pattern of Portal Vein termination, found in 94% of dissections. The ndings of the present Conclusion: study highlight the variations that may occur in the hepatic portal venous system in its extra-hepatic part. Sound knowledge of portal venous anatomy is needed for success in the surgeries of the liver & adjacent viscera.


2019 ◽  
Vol 53 (6) ◽  
pp. 515-519
Author(s):  
Toshiya Nishibe ◽  
Toru Iwahashi ◽  
Kentaro Kamiya ◽  
Masaki Kano ◽  
Keita Maruno ◽  
...  

We present 3 cases of type IIIb endoleak after endovascular aneurysm repair (EVAR) using the Zenith stent graft system. Type III endoleak, like type I endoleak, is a high-pressure, high-risk leak that increases sac pressure up to or even above arterial pressure, and is associated with an increased frequency of open conversions or risk of aneurysm rupture. Type IIIb endoleak is rare but there is much concern that the incidence of type IIIb endoleak is likely to increase hereafter; the mechanism of type IIIb endoleak is deterioration of graft fabric in conjunction with stent sutures. Type IIIb endoleak is difficult to diagnose before rupture. The possibility of type IIIb endoleak should be highly suspected when the continued growth of an excluded aneurysm sac without direct radiologic evidence is observed during follow-up. Type IIIb endoleak can be repaired by relining of the stent graft with additional stent grafts.


2018 ◽  
Vol 25 (5) ◽  
pp. 554-558 ◽  
Author(s):  
Pawel Rynio ◽  
Arkadiusz Kazimierczak ◽  
Tomasz Jedrzejczak ◽  
Piotr Gutowski

Purpose: To demonstrate the utility of a 3-dimensional (3D) printed template of the aortic arch in the construction of a fenestrated and scalloped physician-modified stent-graft (PMSG). Case Report: A 73-year-old woman with descending thoracic aneurysm was scheduled for thoracic endovascular aortic repair after being disqualified for open surgery. Computed tomography angiography (CTA) revealed no proximal landing zone as the aneurysm began from the level of the left subclavian artery, so a fenestrated/scalloped PMSG was planned. To facilitate accurate placement of the openings in the graft, a 3D printed aortic arch template was prepared from the CTA data and gas sterilized. In the operating room, a Valiant stent-graft was inserted into the 3D printed template and deployed. Using ophthalmic cautery, a fenestration and a scallop were created; radiopaque markers were added. The PMSG was successfully deployed with no discrepancy between the openings and the target vessels. Conclusion: A 3D printed aortic arch template facilitates handmade fenestrations and scallops in PMSGs and may improve accuracy and quality.


2020 ◽  
Vol 8 ◽  
pp. 2050313X2095921
Author(s):  
Naoki Yoshioka ◽  
Kensuke Takagi ◽  
Yasuhiro Morita ◽  
Makoto Kawase ◽  
Itsuro Morishima

Arterio-ureteral fistulas are relatively rare, but a potentially life-threatening condition because of the possible massive bleeding. An 82-year-old woman with a history of hysterectomy and irradiation for uterine cancer was treated with ureteric stents for recurrent bilateral ureteral stenosis. During the adjustments of the stent, removing the right ureteric stent immediately resulted in massive hematuria. Computed tomography showed that the right ureter coursed above and seemed to be connected to the right external iliac artery. From the clinical history and computed tomography findings, an arterio-ureteral fistula between the right external iliac artery and right ureter was strongly suspected. The GORE® VIABAHN® VBX Stent Graft was deployed from the common iliac artery to the external iliac artery via a 7-French femoral system, followed by post-dilatation. The patient did not develop any complications or recurrence of hematuria after the procedure during the 11-month follow-up. The VBX is a useful device, with a low- profile device and a size-adjustable balloon-expandable stent that depended on the individual vessel size for post-dilatation. However, there are several concerns, such as risk of infection, stent thrombosis/stenosis, and chronic outcome while using stent grafts for treatment. Patients with arterio-ureteral fistulas who were treated using stent grafts should be carefully followed up.


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