Acute Kidney Injury and Mortality After Fenestrated Endovascular Aortic Repair.

INTRODUCTION: Acute kidney injury (AKI) is a common complication following endovascular aortic repair (EVAR). An association of AKI with patient survival after fenestrated EVAR (FEVAR) is currently under investigation. METHODS: Patients undergoing FEVAR between April 2013 and June 2020 were included in the study. AKI was defined according to acute kidney injury network criteria. Demographic and perioperative data, complications, and survival are reported for the study cohort. The data were analyzed to identify possible predictors of AKI. RESULTS: Two hundred and seventeen patients underwent FEVAR during the study period. Survival at last follow-up (20.4 ± 20.1 mo) was 75.1%. Thirty patients experienced AKI (13.8%). Six of 30 patients with AKI (20%) died within 30 days or in-hospital and 1 (3.3%) progressed to hemodialysis. Within 1 y, renal function had recovered in 23 patients (76.7%). In-hospital mortality was higher in patients with AKI (20% versus 4.3%, P = 0.006). A higher rate of AKI was seen in patients in whom an intraoperative technical complication had been documented (38.5% versus 8.4%, P = 0.001). CONCLUSIONS: Patients undergoing FEVAR are at risk of developing AKI, especially if they experience technical intraoperative complications. Most patients see recovery of renal function within the first 30 days to 1 y, but AKI remains associated with significantly increased in-hospital mortality.

Fenestrated Endovascular Aortic Repair After Failed Endovascular Aortic Repair.

PURPOSE: Fenestrated endovascular aortic repair (FEVAR) is technically more challenging when performed after a failing EVAR procedure (FEVAR after EVAR). This study aims to assess the technical outcome of FEVAR after EVAR and to identify factors that may influence complication rates. METHODS: A retrospective observational study was conducted at a single department of vascular and endovascular surgery. The rate of FEVAR after EVAR compared to primary FEVAR is reported. Complication and primary unconnected fenestration (PUF) rates as well as survival were assessed for the FEVAR after EVAR cohort. PUF rates and operating time were also compared to all primary FEVAR patients. Patient characteristics and technical factors such as number of fenestrations or use of a steerable sheath were assessed as possible influencers on technical success when performing FEVAR after EVAR. RESULTS: Two hundred and nine fenestrated devices were implanted during the study period (2013 to April 2020). Thirty-five patients (16.7% of all FEVAR patients) had undergone FEVAR after EVAR and were included in the study. Overall survival at last follow-up (20.2±19.1 months) was 82.9% in FEVAR after EVAR patients. Rates of technical failure dropped significantly after 14 procedures (42.9% vs. 9.5%; p=0.03). Primary unconnected fenestrations were seen in 3 cases of FEVAR after EVAR (8.6%) and 14 of 174 primary FEVAR cases (8.0%; p>0.99). Operating time for FEVAR after EVAR was significantly higher than for primary FEVAR (301.1±110.5 minutes vs. 253.9±103.4 minutes; p=0.02). The availability of a steerable sheath was a significant predictor of reduced risk of PUFs, whereas age and gender, number of fenestrations or suprarenal fixation of the failed EVAR did not significantly influence PUF rates. CONCLUSION: Fewer technical complications were seen over the study period in FEVAR after EVAR patients. While rates of PUFs were not different from primary FEVAR, operating time was significantly longer in patients undergoing FEVAR for failed EVAR. Fenestrated EVAR can be a valuable and safe tool to treat patients with progression of aortic disease or type Ia endoleak after EVAR but may be more complex to achieve than primary FEVAR. CLINICAL IMPACT: This retrospective study assesses the technical outcome of fenestrated endovascular aortic repair (fenestrated EVAR; FEVAR) after prior EVAR. While rates of primary unconnected fenestrations were not different from primary FEVAR, operating time was significantly longer in patients undergoing FEVAR for failed EVAR. Fenestrated EVAR after prior EVAR may be technically more challenging than primary FEVAR procedures, but could be performed with equally good results in this patient cohort. FEVAR offers a feasible treatment option for patients with progression of aortic disease or type Ia endoleak after EVAR.

Assessment of Pull-out Forces in TEVAR and ANACONDA FEVAR Combination and Early Clinical Results: Creation of a Proximal Landing Zone for FEVAR in Patients with Extent I and Extent IV TAAAs.

BACKGROUND: Although recent data on the treatment of thoracoabdominal aortic aneurysms (TAAAs) are promising, in some cases, the paravisceral segment of the aorta may not be suitable for a branched endograft due to space restrictions. A combination of a fenestrated aneurysm repair (FEVAR) with a thoracic aneurysm repair (TEVAR) may represent a feasible treatment option. The current investigation was performed to assess the stability of a fenestrated Anaconda device implanted into a set of thoracic endografts from different manufacturers. We then assessed our clinical results with the FEVAR/TEVAR combination. METHODS: Pull-out forces were measured in vitro after docking a fenestrated Anaconda graft within the distal end of different TEVAR devices. Anaconda devices were implanted in 28- or 30-mm thoracic tube grafts (oversizing of at least 2 mm: 13.3-21.4; minimum overlap of 15 mm). Continuously increasing longitudinal pull forces of up to 100 N were applied on an Instron Tensile Tester. Initial break point and damage to the endografts were documented. Clinical results of patients treated with such an FEVAR/TEVAR combination at our institution are presented as a second part of this study. RESULTS: Median pull-out forces ranged from 2.38 N to 55.0 N. The highest stability was achieved with 34-mm Anaconda devices in 28-mm thoracic tube grafts. Grafts with either thinner Dacron material or those featuring a polytetrafluorethylene membrane seemed especially vulnerable to punctures and tears caused by the downward-looking hooks of the Anaconda device. Between April 1, 2013 and December 31, 2018, in 28 of 172 patients treated with a fenestrated Anaconda device, prior implantation of a thoracic tube graft was necessary to create a sufficient proximal landing zone. In 25 cases (89.3%), the aneurysm was successfully treated. Although the 30-day reintervention rate in this subgroup was relatively high at 28.6%, none of these was due to a failure of the FEVAR/TEVAR combination. Upon an average follow-up of 15 months, no failure of the graft connection and no type III endoleak due to membrane damage were observed. CONCLUSIONS: The combination of a thoracic tube graft and a fenestrated Anaconda device is a viable option for the treatment of patients with Extent I or IV TAAAs with no adequate landing zone above the celiac trunk. Although pull-out testing has shown good stability with most assessed grafts, the thoracic devices with thicker Dacron membranes seemed to be especially suitable.

Endovascular treatment of hypogastric artery aneurysms.

OBJECTIVE: Internal iliac artery aneurysm (IIAA) is a rare entity. Its treatment can be technically challenging. The aim of this study was to evaluate the treatment possibilities in an era of advanced endovascular techniques and their potential to preserve iliac blood flow while reliably excluding the aneurysm. METHODS: A retrospective analysis of 46 consecutive patients with endovascularly treated IIAA was performed. Data were collected from a single-institution aortoiliac database. The following end points were recorded: technique of aneurysm exclusion, technical success rates, perioperative morbidity and mortality, primary patency, and midterm follow-up. RESULTS: Between September 2009 and May 2016, a total of 46 patients with 55 IIAAs were identified. The majority of patients (n = 39 [84.8%]) had aortoiliac aneurysms and seven had isolated IIAAs (15.2%). The following surgical techniques were used: implantation of iliac branch devices (IBDs; n = 29), occlusion of the internal iliac artery (IIA) by ostium coverage with or without prior coil embolization (n = 23), and other endovascular techniques (n = 3). Primary assisted technical success was achieved in 93.1% of IBD implantations and in 100% of occlusions by ostium coverage and other techniques. Overall 30-day mortality was 4.3% (n = 2) and 0% in electively treated patients. Assisted midterm patency after IBD implantation was 93.1%. Gluteal claudication occurred in seven patients (15.2%) who had undergone intentional or accidental occlusion of the IIA or the superior gluteal artery. Reintervention rates within the midterm follow-up were 13.8% (n = 4) after IBD implantation and 4.3% (n = 1) after coverage of the IIA ostium. No ruptures were observed during follow-up, and no complications occurred during reinterventions. CONCLUSIONS: Implantation of IBD devices for the treatment of hypogastric artery aneurysms shows good technical results with a high primary patency and a low rate of perioperative complications. Although successful aneurysm exclusion while preserving pelvic blood flow is associated with a higher rate of reinterventions during midterm follow-up, it should be taken into consideration, especially in complex endovascular aortoiliac aneurysm repair.

Successful percutaneous access for endovascular aneurysm repair is significantly cheaper than femoral cutdown in a prospective randomized trial.

OBJECTIVE: Because of its minimally invasive nature, percutaneous femoral access for endovascular aneurysm repair (pEVAR) is currently undergoing rapid popularization. Compared with surgical cutdown for femoral access (cEVAR), it offers the advantage of faster recovery after surgery as well as a reduction in wound complications. Despite proposed advantages, the method is largely considered uneconomical because of its reliance on costly closure devices. METHODS: There were 50 patients undergoing EVAR who were enrolled in this randomized prospective single-center trial. Each patient randomly received percutaneous access in one groin and surgical access in the other. The primary end points were access duration and cost. Secondary end points were wound complications and the postoperative pain levels. RESULTS: Surgery was performed per protocol in 44 patients. Mean access times for pEVAR and cEVAR were 11.5 ± 3.4 minutes and 24.8 ± 12.1 minutes (P < .001), respectively. Total access costs were €559.65 ± €112.69 for pEVAR and €674.85 ± €289.55 for cEVAR (P = .016). Eight complications in six patients were attributed to cutdown, none to pEVAR (P = .02). The percutaneously accessed groin was significantly less painful at day 1 and day 5 after surgery (P < .001). An intention-to-treat analysis (N = 50 patients) included six cases of pEVAR conversion due to technical failure in three patients (6%) and change of the operative strategy in another three patients (eg, aortouni-iliac stent graft followed by crossover bypass). The intention-to-treat analysis showed shorter mean overall access time for pEVAR (pEVAR, 14.65 ± 10.20 minutes; cEVAR, 25.12 ± 11.77 minutes; P < .001) and no cost difference between the two methods (pEVAR, €651.29 ± €313.49; cEVAR, €625.53 ± €238.29; P = .65). CONCLUSIONS: Our data confirm proposed potential benefits attributable to the minimally invasive nature of pEVAR while demonstrating cost-effectiveness despite the additional cost of closure devices. Taking into account pEVAR failures still does not increase pEVAR costs over cEVAR. Further considering reduced postoperative pain and wound complications, the technique deserves consideration in suitable patients.

Remote training and evaluation of a simulator-based training course for complex endovascular procedures.

Background: Intimate knowledge of the materials used in endovascular aortic interventions is essential for trainees and supporting staff taking part in an endovascular intervention. Training courses can help to familiarize trainees with the equipment. However, the pandemic has changed the landscape of hands-on training courses significantly. Therefore, we developed a training course including an educational recording of the procedure to transfer knowledge about the materials used during endovascular interventions and radiation exposure reduction. Methods: We produced a video depicting cannulation of the left renal artery in a silicon cast of an aorta and its major side branches under C­arm fluoroscopy. A presentation using the video was given to the trainees. The trainees were randomized into a control and an intervention group. Their performance was filmed and rated on a standardized five-point scale in the style of the OSATS global rating scale. The intervention group was remeasured after additional training time. Results: In total, 23 trainees participated in the training and agreed to have their performance recorded. The control and intervention groups showed no difference in the assessed performance metrics during their initial attempt. However, after receiving additional training, the intervention group significantly improved in all evaluated metrics. Conclusion: Our data add to the growing evidence that simulator-based training can help to increase trainees' understanding and performance of relevant skills. A standardized and evidence-based validation process for simulators could improve their acceptance in the medical field.

[Translational medicine-Development of simulation models for training in vascular surgery]. / Translation gegen die Einbahn ­ Entwicklung von Simulationsmodellen für die gefäßchirurgische Ausbildung.

The establishment of new surgical methods and techniques is associated with a learning curve which can lead to a higher morbidity and mortality for patients during training. To counteract this problem, within the framework of surgical and endovascular training and to transfer the learning curve from the patients to the simulator, life-like models are used and tested. The benefits of such simulator training have been shown in multiple disciplines. This article presents the steps from the conception to the production and validation of a simulator for ultrasound-guided arterial and venous puncture. The goal was to develop a cost-efficient high-fidelity simulator that enables ultrasound-guided percutaneous vascular puncture, direct haptic and visual feedback and the use of some percutaneous devices in a manner as complete and life-like as possible. The finished prototype enables an ultrasound-guided puncture of arteries and veins and the model enables the deployment of endovascular devices and closure systems. To be able to provide and carry out a structured training removed from external influences and challenges is in the interest of clinical departments, trainees and ultimately patient safety. Simulation training on life-like models can provide a valuable contribution in this context and represents a welcome supplement to traditional clinical training.

Exclusion of complex aortic aneurysm with chimney endovascular aortic repair is applicable in a minority of patients treated with fenestrated endografts.

OBJECTIVES: The Medtronic Endurant II stent graft has recently received Conformité Européenne (CE) approval for the use in chimney endovascular aortic repair (ChEVAR) for the treatment for juxtarenal aortic aneurysms. The aim of this study was to assess the percentage of patients treated by fenestrated endovascular repair who would have been alternatively suitable for the treatment by the CE approved Medtronic ChEVAR. METHODS: Preoperative computed tomography scans of 100 patients who underwent fenestrated endovascular aortic repair (FEVAR) between April 2013 and February 2017 were retrospectively assessed for the applicability of the ChEVAR technique according to the Medtronic instructions for use. Eligibility criteria included an aortic neck diameter of 19-30 mm, a minimum infrarenal neck length of 2 mm, a total proximal sealing zone of at least 15 mm, thrombus in the aortic neck in ˂25% of the circumference, and maximum aortic angulations of 60° in the infrarenal, 45° in the suprarenal segment and ˂45° above the superior mesenteric artery. RESULTS: According to CE-approved inclusion criteria, 19 individuals (19%) would have been eligible for ChEVAR. In 81 patients, at least 1 measure was found outside instructions for use: (i) excluding factor was detected in 26 patients, (ii) incongruous measures in 28 patients and in 27 patients, 3-5 measures were outside the instructions for use. The most frequently identified excluding factor was an insufficient infrarenal neck at ˂2 mm length (n = 63; 63%). CONCLUSIONS: Patients with juxta- or pararenal aneurysm treated by FEVAR are in 19% of the cases alternatively suitable for the treatment by ChEVAR within CE-approved instructions for use. While ChEVAR is suitable in many emergency cases, FEVAR offers a broader applicability in an elective setting.

Multicentre experience with an iliac fenestrated device.

OBJECTIVES: The aim of this study was to present a multicentre experience of technical results and mid-term follow-up using a custom-made iliac fenestrated device (Terumo Aortic, Inchinnan, Renfrewshire, UK) for the treatment of iliac aneurysms and endoleaks. METHODS: A multicentre retrospective evaluation of 22 patients (3-12 per institution) with either an iliac artery aneurysm or endoleak treated with an iliac fenestrated device was performed. Data were gathered from 3 departments of vascular and endovascular surgery at 3 European institutions. RESULTS: Ten of the included patients (45.5%) were treated for an endoleak and 12 had aorto-iliac aneurysms (54.5%). Two patients underwent bilateral fenestrated device implantation for a total of 24 devices included in this analysis. Primary technical success was 91.7% (22 of 24 implanted devices). One of the 24 internal iliac arteries could not be cannulated and was covered (primary assisted technical success rate 95.8%) and 1 patient required a relining of the stent graft due to a mid-grade stenosis opposite the internal iliac artery fenestration. Survival at the last available follow-up (mean 15.2 ± 12.0 months, range 0.5-36.6 months) was 90.9%. CONCLUSIONS: The present investigation adds to a growing body of literature on custom-made endografts and their usefulness in achieving endovascular repair without compromising blood flow via important arterial branch vessels, such as the internal iliac artery. It presents encouraging technical and mid-term follow-up data from consecutive patients treated for iliac aneurysms or endoleaks using this custom-made device. The technique may help avoid adverse sequelae associated to a coil-and-cover approach when iliac branch devices are not feasible.

Ultrasound-Guided Percutaneous Arterial Puncture and Closure Device Training in a Pulsatile Model.

OBJECTIVE: The current study assesses the feasibility of in vitro practice of percutaneous puncture techniques in a pulsatile flow-model. DESIGN: Prospective, controlled, randomized study. SETTING: The percutaneous access to endovascular aortic repair is considered safe, but success rates may be dependent on surgeon experience with the technique. PARTICIPANTS: Fourteen vascular surgery trainees and consultants were enrolled and randomized to a study or control group with both groups receiving instructions by a tutor on how to perform ultrasound guided percutaneous puncture and closure using a suture-mediated closure device. The study group received additional hands-on training on a pulsatile flowmodel of the groin and the performance of both groups was then graded. Study group participants were timed during and after their training on the model. RESULTS: The study group achieved higher overall grading than the control group on a 5-point scale with higher scores indicating a better performance (mean overall scores 4.0 ± 0.7 versus 2.8 ± 1.0, respectively; p = 0.03). Experienced participants (more than 20 punctures performed before the study) achieved higher overall scores than trainees (3.8 ± 0.4 versus 2.5 ± 0.8, respectively; p = 0.01). Five participants in the study group could deploy and close the ProGlide closure device correctly without the help of a tutor while being graded (71% in the study versus 0% in the control group; p = 0.02). Study group participants improved their overall score from 3.2 ± 0.9 to 4.0 ± 0.7 during training (p = 0.02). Time needed to complete the puncture and closure reduced from 456 seconds on average before, to 302 seconds after training (p < 0.001). CONCLUSIONS: Study group participants could improve their overall score while working on the simulator. More experienced participants performed better during the simulation, which may indicate the model to be life-like and a potential skills assessment tool. Simulation training may be a valuable adjunct to traditional forms of training when teaching an endovascular technique but is limited by its reliance on simulators and demo devices.

Custom-Made Iliac Fenestrated Device.

Iliac branch devices (IBDs) are undergoing rapid popularization. They allow for treatment of an iliac aneurysm while preserving blood flow to the hypogastric artery. Certain anatomic criteria are necessary for the use of an iliac side branch device to be technically feasible. Custom-made fenestrated iliac stent grafts may provide an alternative when anatomic criteria for an IBD are not met.

Covered endovascular repair of the paravisceral aorta.

Open aortic repair is considered the "gold standard" treatment for aortic occlusive disease. We present the case of an 83-year-old patient with refractory hypertension caused by paravisceral aortic stenosis including both renal arteries and the superior mesenteric artery. We planned an endovascular approach and treated the patient with parallel stent grafts in the paravisceral aorta. At 1.5 years after the operation, the patient was free of hypertensive episodes. Covered endovascular repair of the paravisceral aorta may be a valuable alternative to open aortic repair in patients unfit for open surgery. More research is needed to evaluate the long-term effects of this technique.