Abstract Objective The fenestrated Anaconda endograft (Vascutek/Terumo, Inchinnan, UK) is intended for the treatment of abdominal aortic aneurysms with an insufficient infrarenal landing zone. The ...endografts are custom-made with use of high-resolution, 1-mm-slice computed tomography angiography images. For every case, a nonsterile prototype and a three-dimensional (3D) model of the patient's aorta are constructed to allow the engineers as well as the physician to test-implant the device and to review the fit of the graft. The aim of this investigation was to assess the impact of 3D model construction and prototype testing on the design of the final sterile endograft. Methods A prospectively held database on fenestrated endovascular aortic repair patients treated at a single institution was completed with data from the Vascutek engineers' prototype test results as well as the product request forms. Changes to endograft design based on prototype testing were assessed and are reported for all procedures. Results Between April 1, 2013, and August 18, 2015, 60 fenestrated Anaconda devices were implanted. Through prototype testing, engineers were able to identify and report potential risks to technical success related to use of the custom device for the respective patient. Theoretical concerns about endograft fit in the rigid model were expressed in 51 cases (85.0%), and the engineers suggested potential changes to the design of 21 grafts (35.0%). Thirteen cases (21.7%) were eventually modified after the surgeon's testing of the prototype. A second prototype was ordered in three cases (5.0%) because of extensive changes to endograft design, such as inclusion of an additional fenestration. Technical success rates were comparable for grafts that showed a perfect fit from the beginning and cases in which prototype testing resulted in a modification of graft design. Conclusions Planning and construction of fenestrated endografts for complex aortic anatomies where exact fit and positioning of the graft are paramount to allow cannulation of the aortic branches are challenging. In the current series, approximately one in five endografts was modified after prototype testing in an aortic model. Eventually, success rates were comparable between the groups of patients with a good primary prototype fit and those in which the endograft design was altered. Prototype testing in 3D aortic models is a valuable tool to test the fit of a custom-made endograft before implantation. This may help avoid potentially debilitating adverse events associated with misaligned fenestrations and unconnected aortic branches.
Abstract Objective Endovascular aortic aneurysm repair (EVAR) with a fenestrated device (FEVAR) allows an extension of the proximal sealing zone above the renal arteries to an adequate, healthier ...segment of the aorta. This feature makes FEVAR an option to treat patients with a diseased aortic neck or type Ia endoleak after EVAR. The aim of this investigation was to present a single-center experience with FEVAR for patients with an abdominal aortic endograft in situ compared with primary FEVAR. Methods A prospectively held database on FEVAR patients treated with the fenestrated Anaconda device (Vascutek/Terumo, Inchinnan, Scotland, United Kingdom) at our institution was screened for individuals who had previously undergone EVAR. Results Between April 1, 2013, and July 31, 2016, 94 fenestrated Anaconda devices were implanted at our institution. Twelve patients with prior EVAR were treated for pathology of the proximal neck: type I endoleak (n = 7), for stent migration with aneurysm progression but no visible endoleak (n = 2), and progressive aortic disease at the level of the visceral segment (n = 3). When redo cases and primary FEVARs were compared, primary technical success rates were 58.3% and 87.8% ( P = .02) and primary functional success rates were 91.7% and 95.1%, respectively ( P = .62). Perioperative rate of major deployment-related (14.6% and 16.7%) and systemic complications (8.5% and 8.3%) as well as 30-day mortality (6.1% and 0%; P = .5) were comparable between groups. After an average follow-up interval of 10 months (range, 0-43 months), no late occlusions of connecting stents were observed. The late reintervention rates were 11.0% and 16.7%, respectively ( P = .57). Conclusions The risk of a failure to cannulate one or more visceral arteries through the respective fenestrations was increased in patients who had previously undergone EVAR. This is most likely caused by increased friction between the fenestrated endograft and the failing graft in situ, which may impair the adaption of the unsupported Anaconda device to the aortic wall. As a consequence, fenestrations may not line up perfectly at the respective openings of the visceral or renal arteries, and folding of the fabric may be increased, making cannulation of the fenestrations more difficult.
Covered endovascular repair of the paravisceral aorta Plimon, Markus, MD; Falkensammer, Jürgen, MD; Taher, Fadi, MD ...
Journal of vascular surgery cases and innovative techniques,
09/2017, Letnik:
3, Številka:
3
Journal Article
Recenzirano
Odprti dostop
Abstract 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.
Objective Vascular surgeons perform numerous highly sophisticated and delicate procedures. Due to restrictions in training time and the advent of endovascular techniques, new concepts including ...alternative environments for training and assessment of surgical skills are required. Over the past decade, training on simulators and synthetic models has become more sophisticated and lifelike. This study was designed to evaluate the impact of a 3-day intense training course in open vascular surgery on both specific and global vascular surgical skills. Methods Prospective observational cohort analysis with various parameter measurements of both surgical skills and the technical quality of the finished product, performed before and after 3 days of simulator training of 10 participants (seven male and three female) in a vascular surgery training course. The simulator model used was a conventional carotid endarterectomy with a Dacron patch plasty on a lifelike carotid bench model under pulsatile pressure. The primary end points were assessment of any changes in the participants' surgical skills and in the technical quality of their completed carotid patches documented by procedure-based assessment forms. Scores ranging from 1 (inadequate) to 5 (excellent) were compared by a related-sample Wilcoxon signed test. Interobserver reliability was estimated by Cronbach's alpha (CA). Results A significant improvement in surgical skills tasks was observed ( P < .001). The mean score increased significantly by 21.5% from fair (3.43 ± 0.93) to satisfactory (4.17 ± 0.69; P < .001). The mean score for the quality of the carotid patch increased significantly by 0.96 (27%) from fair (3.55 ± 0.87) to satisfactory (4.51 ± 0.76; P < .01). The median interassessor reliability for the quality of the carotid patch was acceptable (CA = 0.713) and for surgical skills was low (CA = 0.424). Conclusions This study shows that lifelike simulation featuring pulsatile flow can increase surgical skills and technical quality in a highly sophisticated multistep vascular intervention. This training provides comparatively inexpensive and lifelike training possibilities for the adoption and assessment of surgical skills required to perform delicate vascular surgical procedures.
Objectives Vascular graft infection is a rare but serious complication of vascular reconstructive surgery. This in vitro study investigated the antimicrobial efficacy of a new, silver-triclosan ...collagen-coated polyester vascular graft compared with a silver collagen-coated polyester vascular graft alone during the first 24 hours. Methods The antimicrobial efficacy of the investigated vascular grafts was assessed by performing a time-kill kinetic assay following Clinical and Laboratory Institute Standards-approved guidelines M26-A. For the purpose of the experimental study, the ATCC 33591 strain of methicillin-resistant Staphylococcus aureus (American Type Culture Collection, Manassas, Va) was used. All assays were repeated sixfold. Bacterial survival numbers were obtained at 1, 4, 8, 12, and 24 hours using a standard plate count procedure. Bactericidal activity was defined as a 3 log10 reduction factor (logRF), according to the approved guideline M26-A. Results Both antimicrobial vascular grafts achieved >3 logRF and fulfilled the efficacy criterion for bactericidal activity but performed differently in their speed of antimicrobial action. The silver-triclosan vascular graft achieved 3.37 logRF after 8 hours, and the silver vascular graft showed a 4.19 logRF after 24 hours. The silver-triclosan graft yielded significantly lower colony-forming units/mL counts after 4 hours compared with the silver graft (4.29 × 104 vs 1.03 × 106 ; P = .031). Conclusions Both antimicrobial collagen-coated polymer vascular grafts showed bactericidal activity against methicillin-resistant Staphylococcus aureus in vitro. Although the silver-triclosan vascular graft showed a faster antimicrobial efficacy, the silver graft exhibited its antimicrobial properties after 24 hours. Which concept will protect an implanted vascular prosthetic graft better from bacterial contamination and subsequent infection needs to be investigated further in in vivo animal and clinical studies.
Vascular surgical training currently has to cope with various challenges, including restrictions on work hours, significant reduction of open surgical training cases in many countries, an increasing ...diversity of open and endovascular procedures, and distinct expectations by trainees. Even more important, patients and the public no longer accept a “learning by doing” training philosophy that leaves the learning curve on the patient's side. The Vascular International (VI) Foundation and School aims to overcome these obstacles by training conventional vascular and endovascular techniques before they are applied on patients. To achieve largely realistic training conditions, lifelike pulsatile models with exchangeable synthetic arterial inlays were created to practice carotid endarterectomy and patch plasty, open abdominal aortic aneurysm surgery, and peripheral bypass surgery, as well as for endovascular procedures, including endovascular aneurysm repair, thoracic endovascular aortic repair, peripheral balloon dilatation, and stenting. All models are equipped with a small pressure pump inside to create pulsatile flow conditions with variable peak pressures of ∼90 mm Hg. The VI course schedule consists of a series of 2-hour modules teaching different open or endovascular procedures step-by-step in a standardized fashion. Trainees practice in pairs with continuous supervision and intensive advice provided by highly experienced vascular surgical trainers (trainer-to-trainee ratio is 1:4). Several evaluations of these courses show that tutor-assisted training on lifelike models in an educational-centered and motivated environment is associated with a significant increase of general and specific vascular surgical technical competence within a short period of time. Future studies should evaluate whether these benefits positively influence the future learning curve of vascular surgical trainees and clarify to what extent sophisticated models are useful to assess the level of technical skills of vascular surgical residents at national or international board examinations. This article gives an overview of our experiences of >20 years of practical training of beginners and advanced vascular surgeons using lifelike pulsatile vascular surgical training models.
Objective The benefit of carotid surgery in asymptomatic patients with high-grade internal carotid artery stenosis (ICAS) is subject of intense debate, and thus improved preoperative risk ...stratification is mandatory. This study aimed to investigate the predictive value of contralateral ICAS (cl-ICAS) for the preoperative clinical presentation of patients with ipsilateral ICAS (primary outcome). Methods This study was a post hoc analysis of a prospective cohort comprising 485 consecutive patients undergoing carotid endarterectomy for high-grade ICAS. Patients were classified by their clinical presentation, ie, asymptomatic (n = 213) or symptomatic (within 6 months of surgery; n = 272, comprising both transient ischemic attack TIA; n = 163 and stroke n = 109). We investigated the association of cl-ICAS with the primary outcome in adjusted regression models. Results Mean ipsilateral degrees of ICAS were similar in both groups (84% ± 10% vs 84% ± 11%; P = .92), whereas contralateral degrees were significantly higher in the symptomatic group (29% ± 34% vs 38% ± 39%; P = .008). After multivariable regression analysis, cl-ICAS >60% conferred a three times higher preoperative stroke risk (odds ratio, 3.31; 95% confidence interval, 1.98-5.54; P < .001). Inclusion of cl-ICAS significantly improved ( P = .001) ipsilateral combined TIA and stroke risk prediction based on established risk factors (area under the curve, 0.66; 95% confidence interval, 0.60-0.72; P < .001). Conclusions Our study identifies a high contralateral degree of ICAS as an independent predictor of preoperative ipsilateral TIA and stroke in patients with ipsilateral high-grade ICAS. Therefore, such patients might rather benefit from elective carotid surgery and intensive postoperative medical care.
Objective Although endovascular procedures have become popular for the treatment of patients with femoropopliteal occlusive disease, open surgical bypass is still required in a significant proportion ...of patients. Saphenous vein is the conduit of choice, but prosthetic bypass grafts are often necessary. The Peripheral Bypass Grafting: Prospective Evaluation of FUSION Vascular Graft for Above Knee Targets (PERFECTION) trial was performed to assess the clinical outcome of the FUSION vascular graft (Maquet Cardiovascular, Wayne, NJ), a novel bilayer prosthetic graft with an external expanded polytetrafluoroethylene inner layer and an outer knit polyester layer. Methods Eligible study patients included those requiring prosthetic femoral-to-above-knee popliteal bypass for claudication, rest pain, or localized tissue loss without wet gangrene. During a 30-month period ending in March 2012, 117 patients were enrolled in the PERFECTION trial and underwent bypass with FUSION vascular grafts at 10 European investigational sites. Patients were followed up with duplex ultrasound imaging and ankle-brachial indices performed at 30 days, 6 months, and 12 months. The primary efficacy end point was 12-month primary patency of the study graft, assessable in 102 patients. Safety end points included all-cause mortality, major adverse events, amputation, and graft reinterventions. Results The 67 male (57.3%) and 50 female (42.7%) patients averaged 67.8 ± 8.9 years in age and were implanted with 6-mm (25 21.4%), 7-mm (26 22.2%), or 8-mm (66 56.4%) FUSION grafts. The 30-day primary graft patency was 95.3%, with five graft occlusions in the perioperative period. The 12-month primary rate was 85.6%, and the secondary patency rate was 93.2%. Ankle-brachial indices increased from a mean of 0.53 ± 0.20 preoperatively to 0.97 ± 0.16 at 30 days and 0.91 ± 0.22 at 12 months. There were no major amputations through 12 months of follow-up, 15 patients (12.8%) had graft reinterventions, one patient (0.9%) developed a graft infection, and five patients (4.3%) died of unrelated causes. Conclusions The findings of the prospective, multicenter PERFECTION study confirm clinical utility of the FUSION vascular graft through 12 months of follow-up. Patency rates equal or exceed those reported with other nonbioactive vascular grafts. These observations suggest that the FUSION graft is a useful alterative to standard expanded polytetrafluoroethylene grafts and should be considered as an option in patients requiring prosthetic femoral-to-above-knee popliteal arterial reconstruction.
Background Both deficiency and, according to recent reports, excess of vitamin B12 (B12) are associated with increased mortality. Thus, it is difficult to estimate the effect of B12 on overall ...survival, which also depends on folate (FA) in homocysteine lowering. This study aimed to assess FA and B12 serum concentrations associated with long-term survival of vascular surgery patients by means of a prognostic index (PI). Methods This single-center, prospective cohort study comprised 485 consecutive carotid surgery patients. B-vitamin baseline concentrations of B12 and FA were used to compute a PI for postoperative overall survival from January 2003 to January 2012 (mean observation period 102.3 months). Results Increasing B12 serum concentrations showed a nonlinear association with overall survival ( P = .033). A B vitamin-based PI significantly predicted overall (hazard ratio HR per standard deviation = 1.97, confidence interval CI 1.37-2.82; P < .001), cardiovascular (HR = 3.03, CI 1.78-5.14; P < .001), and stroke-free survival (HR = 2.20, CI 1.22-3.98; P = .009), and revealed that the highest adverse event-free survival was predicted by high FA (16.3 ± 12.9 ng/mL) but only moderate B12 (360.3 ± 156.0 pmol/L) baseline concentrations. Conclusions Prediction of increased long-term overall, cardiovascular, and stroke-free survival is based on high FA but only moderate B12 serum concentrations. Excessive B12 concentrations might harbor a potential harm and are no requisite for low homocysteine concentrations. The association between B vitamins and survival might serve either as a tool for risk stratification or, if causative, as effective therapy, if optimal dosing of B vitamins is provided and on-treatment concentrations, including homocysteine and renal functions, are closely monitored.
Background Carotid endarterectomy (CEA) is commonly performed for asymptomatic high-grade internal carotid artery (ICA) stenosis to prevent stroke. However, despite advancing age of the society, for ...patients older than 75 years, there is no recommendation by the European guidelines for CEA, as this age group might not benefit from this intervention due to a limited life expectancy. Objective We assessed N-terminal pro B-type natriuretic peptide (NT pro-BNP) as a predictive marker for long-term survival in this particular patient population in order to stratify patients for an improved surgical outcome. Methods In a nonrandomized single-center clinical trial, we prospectively studied mortality rates of 205 consecutive patients (80 women, 125 men; mean age, 75 ± 10 years) with asymptomatic high-grade ICA stenosis in relation to preoperative plasma NT pro-BNP levels. We estimated cumulative survival over 5 years by Kaplan-Meier curves and established a proportional hazard-model by Cox regression. Results In male patients, higher levels of preoperative NT pro-BNP levels were associated with a significantly increased long-term mortality. Those 75 years or older had the same survival rate as younger patients, if NT pro-BNP levels were low, making them thus eligible for CEA. Conclusions The results of our study suggest that preoperative plasma levels of NT pro-BNP are a valuable tool for the stratification of male patients. Male patients older than 75 years with low levels of NT pro-BNP should be referred for carotid revascularization, as they will most likely enjoy the benefit of surgery.
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