Fusion Imaging for EVAR with Mobile C-arm.

BACKGROUND: Fusion imaging is a technique that facilitates endovascular navigation but is only available in hybrid rooms. The goal of this study was to evaluate the feasibility of fusion imaging with a mobile C-arm in a conventional operating room through the use of an angionavigation station. METHODS: From May 2016 to June 2017, the study included all patients who underwent an aortic stent graft procedure in a conventional operating room with a mobile flat-panel detector (Cios Alpha, Siemens) connected to an angionavigation station (EndoNaut, Therenva). The intention was to perform preoperative 3D computerized tomography/perioperative 2D fluoroscopy fusion imaging using an automatic registration process. Registration was considered successful when the software was able to correctly overlay preoperative 3D vascular structures onto the fluoroscopy image. For EVAR, contrast dose, operation time, and fluoroscopy time (FT) were compared with those of a control group drawn from the department's database who underwent a procedure with a C-arm image intensifier. RESULTS: The study included 54 patients, and the procedures performed were 49 EVAR, 2 TEVAR, 2 IBD, and 1 FEVAR. Of the 178 registrations that were initialized, it was possible to use the fusion imaging in 170 cases, that is, a 95.5% success rate. In the EVAR comparison, there were no difference with the control group (n = 103) for FT (21.9 ± 12 vs. 19.5 ± 13 min; P = 0.27), but less contrast agent was used in the group undergoing a procedure with the angionavigation station (42.3 ± 22 mL vs. 81.2 ± 48 mL; P < 0.001), and operation time was shorter (114 ± 44 vs. 140.8 ± 38 min; P < 0.0001). CONCLUSIONS: Fusion imaging is feasible with a mobile C-arm in a conventional operating room and thus represents an alternative to hybrid rooms. Its clinical benefits should be evaluated in a randomized series, but our study already suggests that EVAR procedures might be facilitated with an angionavigation system.

Predictive Factors of Silent Brain Infarcts after Asymptomatic Carotid Endarterectomy.

BACKGROUND: The optimization of medical treatment regularly challenges the role of carotid surgery for asymptomatic patients. Current research seeks to determine which of these patients will benefit most from surgery. The goal of this study was to identify in a multicenter study, using magnetic resonance imaging (MRI), the risk factors for postoperative silent cerebral ischemic lesions after carotid surgery for asymptomatic stenosis. METHODS: The multicenter, retrospective study included patients with asymptomatic severe carotid stenosis suitable for surgical treatment and who did not have a history of cerebral ischemia. A diffusion MRI scan was performed the day before and in the 3 days after the procedure. An analysis by an independent neuroradiologist determined the presence of preoperative silent ischemia and the appearance of new lesions postoperatively. The analysis also took into account the plaque type, lesions of supra-aortic trunks, the circle of Willis, the type of surgery, and anesthesia, shunt use, and clamp time. RESULTS: Between April 2011 and November 2015, 141 patients were included. The mean degree of carotid stenosis in the patients who underwent surgery was 78.2% ± 6.5, with 9 (6.4%) cases of contralateral stenosis ≥70% and 6 (4.3%) of which were thrombosis. The circle of Willis was incomplete in 23 (16.3%) patients. Twenty-one (14.9%) plaques were of high embolic risk. The preoperative MRI found 34 (24.1%) patients with embolic ischemic lesions. The majority of procedures were eversions performed under general anesthesia, 7 (5%) required a shunt, and the mean clamp time was 39 ± 16 min. The postoperative MRI revealed that 10 (7%) patients had a new ischemic lesion on the operated side. None of these lesions were symptomatic. On multivariate analysis, the risk factors for appearance of a new ischemic lesion on the operated side were significant severe stenosis of the vertebral artery ipsilateral to the lesion (odds ratio [OR] = 9.2, 95% confidence interval [CI] [2.1-39.8], P = 0.003) and insertion of a shunt (OR = 9.1, 95% CI [1.1-73.1], P = 0.039). The 30-day follow-up showed one death at D4 due to hemorrhagic stroke on the operated side and one contralateral stroke. None of the study patients had a myocardial infarction. CONCLUSIONS: In this multicenter study, the rate of silent ischemic lesions in asymptomatic carotid surgery showed 43.3% of preoperative silent ischemic lesions and 9.2% of new silent lesions after surgery. The use of a shunt and presence of ipsilateral vertebral stenosis are risk factors for perioperative embolism.

Cerebrospinal fluid drainage and thoracic endovascular aneurysm repair.

Spinal cord complications including paraplegia and partial neurologic deficits remain a frequent problem during repair of descending thoracic or thoracoabdominal aortic aneurysms. Effective prevention of this dreaded complication is of paramount importance. Among the many adjuncts that have been proposed to prevent spinal cord complications, spinal fluid drainage is one that has been used by numerous teams. The aim of this review is to answer the following question: does spinal fluid drainage afford spinal cord protection during both open and endovascular repair of thoracic or thoracoabdominal aortic aneurysms?

Endovascular Treatment of Asymptomatic Abdominal Aortic Aneurysms in Octogenarians: Factors Influencing Long-term Survival.

BACKGROUND: Beyond the age of 80 years, the preventive treatment of an asymptomatic abdominal aortic aneurysm (AAA) has to be decided in light of the life expectancy which it is difficult to evaluate, but it is important to determine who in this population will benefit from it. The objective of our study was to determine the factors influencing short-term mortality and long-term survival in patients aged 80 years and older after the endovascular treatment of AAAs (EVAR). MATERIAL AND METHODS: We present a retrospective analysis of the prospective databases of 4 French academic departments of vascular surgery, bringing together the data of all the patients presenting an AAA who were treated by EVAR between 1998 and 2011. Logistic regression and multivariate analysis with a Cox survival model were used to determine the factors influencing perioperative and long-term mortality. The cumulative rate of events for the measurement of survival was calculated with the technique of Kaplan-Meier. RESULTS: We treated 345 octogenarians and 339 younger patients. The average follow-up was 40 months. Average survival was 75% at 36 months and 49% at 60 months. There was no evidence of any risk factor influencing mortality at 30 days in the octogenarians. However, chronic kidney disease (odds ratio [OR] = 3.95, P <0.001) and chronic respiratory failure (OR = 2.62, P <0.001) proved to be independent factors of a poor long-term prognosis. CONCLUSIONS: The treatment by stent graft in octogenarians is effective in the long term. The presence of an impaired renal function or respiratory failure in this population could put into question the operative indication.

Preoperative CT-scan-based sizing and in-stent restenosis in peripheral endovascular revascularizations.

Objectives This study evaluates the effect of stent sizing with CT-scan on the incidence of restenosis in peripheral arterial disease. Methods This retrospective study included 59 patients with 66 arterial lesions who underwent a endovascular procedure for peripheral arterial disease between April 2013 and October 2013. All patients had de novo iliac or femoral lesions, were candidates for an endovascular procedure alone and underwent CTA preoperatively. The stent actually implanted, whose dimensions were chosen on the basis of the operator's experience on an intraoperative 2D angiography, was compared to the "ideal" stent chosen retrospectively on the basis of precise lesion sizing by the preoperative CTA. Planning was considered "discordant" if there was a difference in length of more than 20 mm and/or a difference in diameter of more than 1 mm between the ideal stent and the actual stent. Results For iliac lesions, discordance essentially concerned stent diameter (36.1%), whereas stent length was the main reason for discordance for femoral lesions (36.7%). The median length of follow-up was 18 months (range 6-24). For iliac lesions, freedom from restenosis at 24 months was higher for patients with concordant planning (90% vs. 62.5%, p = 0.045). Most restenoses occurred in the external iliac artery, where there was a tendency towards oversizing of the implanted stent. For femoral lesions, the restenosis-free rate at 24 months was higher for patients with concordant planning (77.8% vs. 50%, p = 0.057). A multivariate analysis was conducted on the prediction of restenosis. Among factors, only discordant planning was found to be a significant predictor of restenosis with an odds ratio of 0.115 (95% confidence interval, 0.02-0.674; p = 0.016). Conclusion The absence of sizing for peripheral lesions engenders a tendency to choose the wrong stent, in particular in terms of diameter in iliac arteries and length in femoral arteries.

Evaluation by Magnetic Resonance Imaging of Silent Brain Infarcts in Preoperative and Postoperative Asymptomatic Carotid Surgery.

BACKGROUND: To report the prevalence of silent brain infarcts (SBI) at magnetic resonance imaging (MRI) before and after surgery for asymptomatic high grade carotid stenosis. METHODS: This is a single center retrospective observational study. Asymptomatic patients who underwent carotid endarterectomy between October 2012 and October 2014 were included. The preoperative assessment included a Doppler and a computed tomographic (CT) scan dating less than 3 months. A neurological examination was performed during the anesthesia consultation and in the 15 days before surgery. An MRI angiography was performed the day before and 3 days after surgery and was analyzed by an independent neuroradiologist. Preoperative analysis focused on the presence of ischemic events at MRI. The type of plaque, the supra aortic trunk lesions, and the quality of the circle of Willis were analyzed using Doppler and CT scanning. Postoperatively, we searched for signs of postoperative ischemic events at MRI. RESULTS: Forty-one patients were included (85.4% of men), and the mean age was 72.4 ± 8.3 years. We noted 7 (17.1%) contralateral stenoses (>50%) and 2 (4.9%) contralateral thromboses, 6 (14.6%) vertebral stenoses, and 7 (17.1%) abnormalities of the circle of Willis. The morphological analysis described 6 unstable plaques including 4 ulcerated, 1 pseudodissection, and 1 intraplaque hemorrhage. Preoperatively, we noted the presence of 21 (51.2%) ischemic lesions including 9 (21.9%) multiple lacunar ischemic events and 12 (29.3%) silent arterial territory infarcts. Eversion was performed for all patients except for 6 (14.6%), for whom a bypass was necessary. No deaths or major complications were observed in the 30 postoperative days. Postoperatively, MRI showed 3 (7.3%) asymptomatic recent ischemic strokes, 1 ipsilateral middle cerebral artery (MCA) stroke, and 2 contralateral (cerebellar and MCA) strokes. CONCLUSIONS: Patients with asymptomatic significant carotid stenosis show many preoperative SBI indicating a significant embolic risk. It is difficult to conclude about intraoperative embolic risk, but we hope that more data could demonstrate the importance of MRI for the preoperative evaluation of carotid plaques and brain parenchyma, to identify high-risk embolic patients.

French multicenter experience with the GORE TIGRIS Vascular Stent in superficial femoral and popliteal arteries.

BACKGROUND: Preliminary results in small single-center studies after stenting with the GORE TIGRIS Vascular Stent (W. L. Gore & Associates, Flagstaff, Ariz) show promising short-term primary patency rates, but larger, multicenter studies are needed. This study therefore investigated the performance of the GORE TIGRIS Vascular Stent at three different centers in France in patients with symptomatic peripheral artery disease. METHODS: This retrospective, single-arm, multicenter cohort study included 215 patients with peripheral artery disease (Rutherford-Becker category 2-6) who were treated with the GORE TIGRIS Vascular Stent, a dual-component stent consisting of a nitinol wire frame combined with a fluoropolymer-interconnecting structure. The efficacy end point was primary patency defined by freedom from binary restenosis as derived by duplex ultrasound imaging until 2 years after the intervention. Primary, secondary, and primary assisted patency rates at 3, 6, 12, 18, and 24 months were estimated by Kaplan-Meier analysis. RESULTS: The GORE TIGRIS Vascular Stent was used to successfully treat 239 lesions, of which 141 lesions were located in the superficial femoral artery and 98 in the popliteal artery. Patients were a mean age of 74 ± 12 years. Mean lesion length was 86.8 ± 44.7 mm. After 12 and 24 months, the overall primary patency rates were 81.5% and 67.2%, respectively, and primary assisted patency was 94.9% and 84.8%. Secondary patency was achieved in 99.1% at 24 months. CONCLUSIONS: Our multicenter experience with the GORE TIGRIS Vascular Stent demonstrates continued good results at 2 years for endovascular treatment of challenging obstructive superficial femoral artery and popliteal artery disease.

Systematic Review and Meta-Analysis of Preoperative Risk Factors of Type II Endoleaks after Endovascular Aneurysm Repair.

BACKGROUND: Type II endoleaks (T2Es) remain the Achilles heel of endovascular aneurysm repair (EVAR), involving a close follow-up and sometimes leading to reintervention. Identifying risk factors impacting T2Es is of concern to improve decision making and optimize follow-up. However, it has led to contradictory results, with supporting evidence for the majority of factors being weak. METHODS: A systematic review and meta-analysis was conducted to study risk factors of T2Es following EVAR to identify risk factors and measure their dedicated strength of association. Using a literature search of MEDLINE, EMBASE, and the Cochrane Library, 31 retrospective studies including a total of 15,793 patients were identified and fulfilled the strict specified inclusion criteria. Random-effects meta-analysis was conducted for each factor to combine effect estimate across studies. A total of 21 factors related to demography, preoperative treatment, comorbidity, and morphology were statistically pooled. RESULTS: On the basis of the pooled odds ratios and their 95% confidence intervals, patency of aortic side branches, represented by the patency of the inferior mesenteric artery, lumbar arteries, or total number of aortic side branches, were found to be significant harmful risk factors of T2Es. Women were also found to have nearly significant higher risk of developing T2Es than men. On the contrary, the following were found to have a significant protective role: smoking, peripheral artery disease, and thrombus load, represented by the maximum thickness at the maximum aneurysm diameter, the presence of circumferential thrombus, or the presence of thrombus at the level of inferior mesenteric artery. CONCLUSION: Identifying significant risk factors of development of T2Es is mandatory to improve decision making and optimize surveillance planning in EVAR.

Predictive Models of Complications after Endovascular Aortic Aneurysm Repair.

BACKGROUND: The risk of long-term complications after endovascular aneurysm repair (EVAR) is still higher than open surgery and is a critical issue. This study aims to make available reliable statistical predictive models of complications after EVAR. METHODS: Two hundred and thirteen patients who underwent EVAR between 2002 and 2012 were included in this study. The preoperative computed tomography scans were analyzed with a dedicated workstation to provide spatially correct 3-dimensional data. Age, gender, operation-related factors, and 21 morphologic variables were measured and included in the analyses. Five postoperative outcomes were studied. After an initial selection of predictors based on univariate analysis, binomial logistic regression models were proposed for each outcome. The ability to predict each outcome was assessed with receiver operating characteristic curves considering that an area under the curve (AUC) > 0.70 is generally considered sufficiently accurate. RESULTS: The mean age was 74.8 ± 8.6 years with a mean follow-up of 43.8 ± 22.1 months. Respectively, rates and risk factors of each outcome were 25.3% (n = 51) for abdominal aortic aneurysm (AAA) enlargement (age, number of patent sac branches, iliac calcifications and tortuosity, aneurysmal thrombus), 7% (n = 15) for type IA endoleak (neck calcification and AAA diameter), 3.7% (n = 8) for type IB endoleak (iliac tortuosity, AAA diameter, neck thrombus), 19.8% (n = 40) for type II endoleak (female, number of patent sac branches), and 25.9% (n = 55) for reintervention from any cause (neck calcification). The risk associated to each outcome can be calculated with a combination of these different preoperative variables. AUC for each outcome were 79.6% for AAA enlargement, 70.4% for reintervention, 81.3% for type IA endoleak, 92.3% for type IB endoleak, 70.6% for type II endoleak. CONCLUSIONS: This study shows that an exhaustive description of the preoperative anatomy before EVAR is a powerful and reliable tool to predict the risk of developing the most common complications after EVAR.

Interest of fusion imaging and modern navigation tools with hybrid rooms in endovascular aortic procedures.

Because of the emergence of hybrid operating rooms, cone-beam CT scans (CBCT) allow new intraoperative imaging to be produced. Image fusion (3D preoperative CT scan overlaid onto 2D live fluoroscopy image) is the most popular application and makes it possible to navigate throughout the aorta and its branches without having to make use of an additional injection, and allows a reduction to be achieved in the quantity of contrast medium and irradiation required during complex procedures. Planning-oriented software available in hybrid rooms makes it possible to adjust to the patient and the nature of the procedure, the information that is relevant during the operation. CBCT can also be used as a diagnostic tool at the end of a procedure for the detection of endoleaks and could replace routine CT scans made during the first month following the procedure, indirectly contributing again to a reduction of X-ray and contrast agent doses.

Endovascular Treatment of Infrarenal Aneurysms: Comparison of the Results of Second- and Third-Generation Stent Grafts.

BACKGROUND: The stent grafts used for endovascular abdominal aortic repair (EVAR) profited from many technological changes since their appearance. The objective of this study was to compare the medium-term results of the second- and third-generation stent grafts. METHODS: Three hundred thirty-four patients treated by EVAR between 2005 and 2013 were included in this retrospective study. Demographic, anatomical, perioperative, and follow-up data were collected in a prospective way in an electronic database and compared between 2 groups. The preoperative angio-computed tomographies were all analyzed in depth on a suitable three-dimensional work station. Group 1 (n = 219) represented the patients treated by second-generation stent grafts (Medtronic Talent(®), Cook Medical Zenith Flex(®), Vascutek-Terumo Anaconda(®), Gore Excluder low-porosity(®)) and group 2 (n = 115) represented the patients treated with third-generation stent grafts (Medtronic Enduring I and II(®), Cook Medical Zenith LP(®), Gore Excluder C3(®)). RESULTS: The mean follow-up was 42.4 ± 26.8 months with a longer duration in group 1 (52.4 ± 27.2 vs. 23.2 ± 10.9 months, P < 0.0001). The patients of group 2 had significantly more risk factors and cardiovascular comorbidities (coronary disease, tobacco addiction, dyslipidemia, peripheral arterial disease, chronic renal insufficiency). Anatomical characteristics were similar in the 2 groups, in particular regarding the iliac arteries which were significantly more calcified and had a smaller diameter in group 2. The rate of perioperative complications was similar in the 2 groups, in particular for complications related to the iliac axes (3.7% vs. 2.6%, P = 0.96). During the follow-up, there was no significant difference between the 2 groups in the rates of survival, reinterventions, or endoleaks and the progression of the aneurysmal sac. CONCLUSIONS: This study shows that third-generation stent grafts allow results comparable with those of the second-generation stent grafts in spite of more complex iliac anatomies. These results make it possible to expand the indications of EVAR to patients presenting more cardiovascular comorbidities without increasing the risk of complications in the short and medium term.

Sealing zones have a greater influence than iliac anatomy on the occurrence of limb occlusion following endovascular aortic aneurysm repair.

Limb occlusion is a well-known complication following endovascular aortic aneurysm repair (EVAR), and it very often leads to reoperation. The aim of this study is to identify predictive factors for limb occlusion following EVAR. Two hundred and twenty-four patients undergoing EVAR between 2004 and 2012 were included in this retrospective study. Demographics, anatomic, and follow-up data were compared between two groups (with or without thrombosis). Preoperative anatomy was analyzed with a dedicated workstation, using the Society of Vascular Surgery reporting standards. Eleven (4.9%) patients presented with a limb occlusion during follow-up (46 ± 12 months). Univariate analyses were first performed to investigate the influence of preoperative variables on limb occlusion. Then, variables with a p value <0.1 were included in the multivariate analysis and showed that in the occlusion group there was a greater rate of chronic renal failure (18.2% vs. 3.8%, p = 0.012), a more frequent occurrence of distal landing zones in the external iliac artery (15.4% vs. 2.1%, p = 0.006), and a smaller aortic neck diameter (21.0 ± 2.9 mm vs. 23.6 ± 3.3 mm, p = 0.014). Although iliac anatomy does not appear to have a significant influence on limb occlusion rate in the multivariate analysis, proximal and distal sealing zones appear to be involved in this complication.

Long-Term Results of Large Stent Grafts to Treat Abdominal Aortic Aneurysms.

BACKGROUND: Open surgery and endovascular treatment are currently the 2 methods of treatment for abdominal aortic aneurysms (AAAs). Although in open surgery, the proximal diameter of the implanted prostheses seldom exceeds 24 mm, endovascular aneurysm repair (EVAR) makes it possible to use stent grafts up to 36 mm in diameter. The aim of this study was to compare the long-term results of these large stent grafts compared with the others. METHODS: A total of 908 patients operated between 1998 and 2012 for a nonruptured AAA with an infrarenal stent graft were enrolled in this multicentric retrospective study. The patients in whom the proximal diameter of the principal component of the stent graft was above 32 mm belonged to group 1 (n = 170) and the others belonged to group 2 (n = 738). The qualitative and quantitative data were compared with the chi-squared test and the t-test, respectively. The long-term data were analyzed with the log-rank test and Kaplan-Meier curves. RESULTS: Mean age of the patients was 75 ± 8.3 years, and the average follow-up duration was 38 ± 28.2 months. There was no difference between the 2 groups regarding demographic data, risk factors except chronic renal insufficiency (30.6% in group 1 vs. 21.2%, P = 0.011), and the proportion of obese patients (26.2% vs. 17.7%, P = 0.02). Concerning the preoperative anatomic features, there was a significant difference between the groups concerning the length of the neck (25.5 ± 10.1 vs. 28.3 ± 12.6 mm, P = 0.008), the maximum diameter of the AAA (58 ± 10.1 vs. 56.1 ± 10.1 mm, P = 0.027), and the oversizing (18.1 ± 8.3% in group 1 vs. 16.8 ± 7.4% in group 2, P = 0.043). There was no difference of the postoperative rates of complications, technical failure, endoleaks, and death. In the long run, analyses of survival showed that the rates of proximal endoleaks (13% vs. 3.9%, P < 0.0001) and of reintervention (24.1% vs. 14.7%, P = 0.009) were higher in group 1. There was no significant difference between the 2 groups regarding the evolution of the aneurysmal sac, the long-term rate of death from all causes or in relation to the aneurysm. CONCLUSIONS: Our results suggest that large stent grafts are more at the risk of proximal endoleak and reintervention in the long run. However, there were no differences observed in mortality or evolution of the aneurysmal sac in the patients treated by EVAR with wide neck during the period of follow-up.

Prediction of deformations during endovascular aortic aneurysm repair using finite element simulation.

During endovascular aortic aneurysm repair (EVAR), the introduction of medical devices deforms the arteries. The aim of the present study was to assess the feasibility of finite element simulation to predict arterial deformations during EVAR. The aortoiliac structure was extracted from the preoperative CT angiography of fourteen patients underwent EVAR. The simulation consists in modeling the deformation induced by the stiff wire used during EVAR. The results of the simulation were projected onto the intraoperative images, using a 3D/2D registration. The mean distance between the real and simulated guidewire was 2.3±1.1mm. Our results demonstrate that finite element simulation is feasible and appear to be reproducible in modeling device/tissue interactions and quantifying anatomic deformations during EVAR.

Perioperative evaluation of iliac ZBIS branch devices: a French multicenter study.

BACKGROUND: The purpose of this study was to evaluate short-term results of endovascular treatment of common iliac artery (CIA) aneurysms without a distal neck by using iliac branch devices (IBDs), which enable maintenance of antegrade perfusion to the internal iliac artery (IIA). METHODS: Our investigation was done in a prospective, multicenter, nonrandomized manner. IBD were implanted to exclude CIA aneurysms with a diameter >25 mm in patients unfit for open repair. The stent grafts were designed based on preoperative angio-CT findings. A covered stent implantation between the IBD and the target IIA was performed during the same surgical procedure. Angio-CT was performed within the 30 days after the procedure. From January 2009 to April 2010, 39 patients were included in our study (38 men and 1 woman, mean age 73 years). RESULTS: The CIA aneurysm (mean diameter 32.3 mm) was isolated in 15 patients and associated with an abdominal aorta aneurysm (mean diameter 66 mm) in 24 patients. The IBD was systematically connected to a bifurcated aortobiiliac stent graft. The bifurcated stent graft was implanted during the same procedure in all patients, except for two who had a bifurcated stent graft history. Median surgery time, fluoroscopy time, and volume of contrast product were 192 (range 90-360) minutes, 32 (10-120) minutes, and 150 (60-352) mL, respectively. In 37 patients (95%), the internal iliac branch was patent at the end of the surgery. In two patients (5%), it was occluded, entailing a subischemic colic episode and buttock claudication in one of them. To treat a type I endoleak, a proximal extension partially covering a renal artery was implanted during the same surgery. A type III endoleak was diagnosed on the postoperative angio-CT. In three patients, a cross-over femorofemoral bypass was performed for an external iliac leg thrombosis (and for an internal iliac branch thrombosis in one case). In all, at 30 days, no death was reported and the success rate was 90% (three leg stenoses and a type III endoleak). CONCLUSIONS: IBD implantation to maintain an antegrade internal iliac perfusion is possible and has shown promising early success. Our results can be compared with those in the published literature. A learning curve will be needed to improve the technical success rate.

Computer-aided surgery: concepts and applications in vascular surgery.

Computer-aided surgery makes use of a variety of technologies and information sources. The challenge over the past 10 years has been to apply these methods to tissues that deform, as do vessels when relatively rigid flexible objects are introduced into them (Lunderquist rigid guide wire, aortic prosthesis, etc) Three stages of computer-aided endovascular surgery are examined: sizing, planning, and intraoperative assistance. The authors' work shows that an approach based on optimized use of the imaging data acquired during the various observation phases (pre- and intraoperative), involving only lightweight computer equipment that is relatively transparent for the user, makes it possible to provide useful (ie, necessary and sufficient) information at the appropriate moment, in order to aid decision making and enhance the security of endovascular procedures.

Preoperative predictive factors of aneurysmal regression using the reporting standards for endovascular aortic aneurysm repair.

BACKGROUND: Aneurysmal regression is a reliable marker for long-lasting success after endovascular aneurysm repair (EVAR). The aim of this study was to identify the preoperative factors that can predictably lead to aneurysmal sac regression after EVAR, according to the reporting standards of the Society for Vascular Surgery and the International Society of Cardiovascular Surgery (SVS/ISCVS). METHODS: From 199 patients treated by EVAR between 2000 and 2009, 164 completed computed tomography angiographies and duplex scan follow-up images were available. All computed tomography angiographies for enrolled patients in this retrospective study were analyzed with Endosize software (Therenva, Rennes, France) to provide spatially correct 3-dimensional data in accordance with SVS/ISCVS recommendations. Anatomic parameters were graded according to the relevant severity grades. A severity score was calculated at the aortic neck, the abdominal aortic aneurysm, and the iliac arteries. Clinical and demographic factors were studied. Patients with aneurysmal regression >5 mm were assigned to group A (mean age, 71.4 ± 8.9 years) and the others to group B (76.3 ± 8.3 years). RESULTS: Aneurysmal regression occurred in 66 patients (40.2%; group A). Univariate analyses showed smaller severity scores at the aortic neck (P = .02) and the iliac arteries (P = .002) in group A and calcifications and thrombus were less significant at the aortic neck (P = .003 and P = .02) and at the iliac arteries (P = .001 and P = .02), and inferior mesenteric artery patency was less frequent (68.2% vs 82.7%, P = .04). Two multivariate analyses were done: one considered the scores and the other the variables included in the scores. In the first, the patients of group A were younger (P = .002) and aortic neck calcifications were less significant (P = .007). In the second, group A patients were younger (P < .001) and the aortic neck scores were smaller (P = .04). There was no difference between the two groups in the type of implanted endoprosthesis or in the follow-up (group A: 46.4 ± 24 months; group B: 47.2 ± 22 months; P = .35). CONCLUSIONS: In this study, the young age of the patients and their aortic neck quality, in particular the absence of neck calcification, appear to have been the main factors affecting aneurysm shrinkage, such that they represent a target population for the improvement of EVAR results.

Evolution of the upper and lower landing site after endovascular aortic aneurysm repair.

BACKGROUND: The evolution and correlation between the aortic neck and distally located iliac necks after endovascular treatment of abdominal aortic aneurysms (AAAs) was studied. METHODS: Of 179 patients who had undergone AAA repair between 2003 and 2007, 61 received the same radiologic follow-up and were included in this retrospective study. Data for 61 aortic necks and 115 iliac arteries were analyzed using the preoperative scan, 1-month visit, and final follow-up, with a minimum mean follow-up of 24 ± 15.2 months. Three measurements were taken of the aortic neck: subrenal (D1a), 15 mm below the lowest renal artery (D1b), and at the origin of the aneurysm (D1c). Three measurements were taken at the level of the iliac arteries: origin (Da), middle (Db), and the iliac bifurcation (Dc). These measurements were analyzed using analysis of variance and Spearman correlation coefficient. The results were evaluated for subsequent endoleaks, migrations, and reinterventions. All diameters were compared between patients with a regression of >10% in the greatest diameter of AAA at last follow-up (group A, n = 35) and those without (group B, n = 26). RESULTS: All diameters (in mm) increased significantly over time at the level of the proximal neck (D1a = 3.7 ± 2.8, P = .018; D1b = 4.4 ± 2.5, P = .016; D1c = 4.3 ± 3.1, P = .036) and iliac arteries (Da = 2.1 ± 0.2, P = .0006; Db = 2.5 ± 0.5, P = .0006; Dc = 3 ± 0.7, P = .007). The increase in diameters at the proximal neck and iliac arteries evolved independently (insignificant correlation), with the exception of D1b and Dc (P = .006), which showed a weak correlation (r = 0.363). The group A patients presented increases in all diameters, although to a less significant extent (P < .05) than group B patients. During follow-up, a proximal endoleak and a distal endoleak occurred, both requiring reintervention. CONCLUSIONS: Our results show a trend toward dilatation of the aortic neck and iliac arteries, with no correlation between the two levels, even in patients with a regression of the aneurysm sac during follow-up. Although this study found no correlation with the occurrence of endoleaks, our results suggest the need for a longer follow-up, especially on the landing sites.

Sizing for endovascular aneurysm repair: clinical evaluation of a new automated three-dimensional software.

BACKGROUND: To assess the reproducibility and accuracy of the sizing procedure before aortic endograft implantation using new sizing automated software as compared with standard radiological procedures. METHODS: On the basis of original spiral-computed tomography images, the sizing of 32 patients with abdominal aortic aneurysm treated by endovascular aneurysm repair (EVAR) was retrospectively compared. The first sizing was performed by a radiologist using a standard workstation (General electrics) and software (Advanced vessel analysis). The second was performed twice by two surgeons using a personal computer with automatic three-dimensional sizing software (Endosize; Therenva, Rennes, France). All diameters and lengths required before EVAR were measured (17 items). Moreover, 13 qualitative criteria regarding EVAR feasibility, including neck length, were compared. Intra- and interobserver variability with Endosize, as well as the variability between the two measurement methods were analyzed using the intraclass correlation coefficient (ICC) and Bland and Altman's method. Qualitative variables were analyzed using Fischer's exact test and kappa coefficient. RESULTS: Intraobserver variability with Endosize proved to be efficient. None of the ICCs were lower than 0.9, and more than 90% of the absolute differences between two measurements were less than 2 mm. Interobserver variability with Endosize was assessed in a similar manner. Measurement variability of vessel diameters was less marked than that of vessel lengths. This trend was observed for all datasets. Comparison of the two measurement methods demonstrated a good correlation (minimum ICC = 0.697; maximum ICC = 0.974), although less so than that observed using Endosize. Mean time consumption using Endosize was 13.1 ± 4.53 minutes (range: 7.2-32.7). Analysis of the alarm sets demonstrated a high agreement between observers (kappa coefficient = 0.81). CONCLUSIONS: Sizing using the Endosize software is as reliable as conventional radiological procedures. Sizing by surgeons using an automated, user-friendly, and mobile tool appears to be reproducible.

Value of cutting balloon angioplasty for limb salvage in patients with obstruction of popliteal and distal arteries.

Popliteal-to-distal bypass is still the gold standard for limb salvage. However, some patients, especially elderly or diabetic patients, are not eligible for such treatment; and problems may arise, including poor healing of distal surgical wounds, delayed resumption of ambulation, and prolonged hospitalization. This prospective multicenter study carried out on an intent-to-treat basis includes 53 extremities in 48 patients presenting critical ischemia due to infrageniculate arterial lesions with no proximal lesions. Two populations were isolated: diabetic patients (56.6%) and elderly patients over 80 years (45%). In 82% of cases the arterial lesions were long, i.e., more than 1 cm. The limb salvage rate at 1 year was 81%. Postoperative mortality was 9%, and mortality at 1 year was 22.6%. These results show that cutting balloon angioplasty can be proposed as primary treatment in patients with critical ischemia due to popliteal and distal artery lesions.