Infrarenal Endovascular Aneurysm Repair Research Articles

Editor's Choice – Estimated Radiation Dose to the Operator During Endovascular Aneurysm Repair

To estimate operator organ doses from fluoroscopically guided infrarenal endovascular aneurysm repair (EVAR) procedures, using the detailed exposure information contained in radiation dose structured reports. Conversion factors relating kerma area product (PKA) to primary operator organ doses were calculated using Monte Carlo methods for 91 beam angles and seven x-ray spectra typical of clinical practice. A computer program was written, which selects the appropriate conversion factor for each exposure listed in a structured report and multiplies it by the respective PKA. This system was used to estimate operator doses for 81 EVAR procedures for which structured reports were available. The impact of different shielding scenarios and variations in operator position was also investigated. Without any shielding, the median estimated effective dose was 113 μSv (interquartile range [IQR] 71, 252 μSv). The highest median organ doses were for the colon (154 μSv, IQR 81, 343) and stomach (133 μSv, IQR 76, 307). These dose estimates represent all exposures, including fluoroscopy and non-fluoroscopic digital acquisitions. With minimal shielding provided by 0.25 mm of Pb covering the torso and upper legs, the effective dose was reduced by a factor of around 6. With additional shielding from ceiling and table shields, a 25 to 50 fold reduction in dose is achievable. Estimated doses were highest where the primary beam was pointed directly away from the operator. The models suggest that with optimal use of shielding, operator doses can be reduced to levels equivalent to one to two days of natural background exposure and well below statutory dose limits.

Technological Advances to Address the Challenging Abdominal Aortic Aneurysm Neck.

There have been significant technologic advances in endovascular aortic therapies since the introduction of conventional infrarenal endovascular aortic aneurysm repair (EVAR). These advances have sought to address the weaknesses of conventional EVAR- particularly the difficult or "hostile" infrarenal aortic aneurysm neck. We review anatomical features that create a hostile neck and the most recent advancements to overcome these limitations. EndoAnchors replicate open suture fixation to seal endograft to aortic tissue and have been shown to be useful as a prophylactic measure in short, angulated necks as well as therapeutic for type Ia endoleaks. Fenestrated EVAR (FEVAR) devices such as the Z-fen (Cook Medical, Bloomington, IN, USA) raises the seal zone to the suprarenal segment while maintaining renal perfusion. Finally, multibranch aortic grafts such as the Thoracoabdominal Branch Endoprosthesis (Tambe; W. L. Gore & Associates, Flagstaff, AZ, USA) raise the seal zone above the visceral segment and can be used off the shelf with promising results.

Major adverse cardiac events after elective infrarenal endovascular aortic aneurysm repair.

There is a significant cardiac morbidity and mortality after endovascular aneurysm repair (EVAR). However, information about long-term risk of cardiac events after EVAR and potential predictors is lacking. Therefore, the aim of this study was to determine incidence and predictors of major adverse cardiac events (MACE) at 1 and 5years after elective EVAR for infrarenal abdominal aortic aneurysms. Baseline, perioperative, and postoperative information of 320 patients was evaluated. The primary outcome was the incidence of MACE after EVAR, which was defined as acute coronary syndrome, unstable angina pectoris, de novo atrial fibrillation, hospitalization for heart failure, mitral valve insufficiency, revascularization (including percutaneous coronary intervention and coronary artery bypass grafting), as well as cardiovascular and noncardiovascular death. Kaplan-Meier analyses were performed to determine incidences of MACE, MACE excluding noncardiovascular death and cardiac events by excluding noncardiovascular and vascular death from MACE. Predictors of MACE were identified using univariate and multivariate binary regression analysis. Through 1 and 5years of follow-up after EVAR, freedom from MACE was 89.4% (standard error [SE], 0.018) and 59.8% (SE, 0.033), freedom from MACE excluding noncardiovascular death was 94.7% (SE, 0.013) and 77.5% (SE, 0.030) and freedom from cardiac events was 96.0% (SE, 0.011) and 79.1% (SE, 0.030), respectively. Predictors for MACE within 1year were American Society of Anesthesiologists (ASA) score of III or IV (odds ratio [OR], 3.17; 95% confidence interval [CI], 1.52-6.59) and larger abdominal aortic diameter (OR, 1.04; 95% CI, 1.01-1.08). A history of atrial fibrillation (OR, 0.14; 95% CI, 0.03-0.60) was a negative predictor factor. Predictors for MACE through 5years were a history of heart failure (OR, 4.10; 95% CI 1.36-12.32) and valvular heart disease (OR, 2.31; 95% CI, 0.97-5.51), American Society of Anesthesiologists score of 3 or 4 (OR, 1.66; 95% CI, 0.96-2.88), and older age (OR, 1.04; 95% CI, 1.01-1.08). MACE is a common complication during the first 5years after elective EVAR. Cardiac diseases at baseline are strong predictors for long-term MACE and potentially helpful in optimizing future postoperative long-term follow-up.

Major adverse cardiac events after elective infrarenal endovascular aortic aneurysm repair

Major adverse cardiac events after elective infrarenal endovascular aortic aneurysm repair

Mortality analysis of endovascular aneurysm sealing versus endovascular aneurysm repair

BackgroundEndovascular aneurysm sealing (EVAS), using the Nellix endovascular aneurysm sealing system, has been associated with high reintervention and migration rates. However, prior reports have suggested that EVAS might be related to a lower all-cause mortality compared with endovascular aneurysm repair (EVAR). In the present study, we examined the 5-year all-cause mortality trends after EVAS and EVAR. MethodsWe compared the 333 EVAS patients in the EVAS-1 Nellix U.S. investigational device exemption trial with 16,497 infrarenal EVAR controls from the Vascular Quality Initiative, treated between 2014 and 2016, after applying the exclusion criteria from the investigational device exemption trial (ie, hemodialysis, creatinine >2.0 mg/dL, rupture). As a secondary analysis, we stratified the patients by aneurysm diameter (<5.5 cm and ≥5.5 cm). We calculated propensity scores after adjusting for demographics, comorbidities, and anatomic characteristics and applied inverse probability weighting to compare the risk-adjusted long-term mortality using Kaplan-Meier and Cox regression analyses. ResultsAfter weighting, the EVAS group had experienced similar 5-year mortality compared with the controls from the Vascular Quality Initiative (EVAS vs EVAR, 18% vs 14%; hazard ratio [HR], 1.1; 95% confidence interval [CI], 0.71-1.7; P = .70). The subgroup analysis demonstrated that for patients with an aneurysm diameter of <5.5 cm, EVAS was associated with higher 5-year mortality compared with EVAR (19% vs 11%; HR, 2.4; 95% CI, 1.7-4.7; P = .013). In patients with an aneurysm diameter of ≥5.5 cm, EVAS was associated with lower mortality within the first 2 years (2-year mortality: HR, 0.29; 95% CI, 0.13-0.62; P = .002). However, compared with EVAR, EVAS was associated with higher mortality between 2 and 5 years (HR, 1.9; 95% CI, 1.2-3.0; P = .005), with no mortality difference at 5 years (18% vs 17%; HR, 0.82; 95% CI, 0.4-1.4; P = .46). ConclusionsWithin the overall population, EVAS was associated with similar 5-year mortality compared with EVAR. EVAS was associated with higher mortality for those with small aneurysms (<5.5 cm). For those with larger aneurysms (≥5.5 cm), EVAS was initially associated with lower mortality within the first 2 years, although this advantage was lost thereafter, with higher mortality after 2 years. Future studies are required to evaluate the specific causes of death and to elucidate the potential beneficial mechanism behind sac obliteration that leads to this potential initial survival benefit. This could help guide the development of future grafts with better proximal fixation and sealing that also incorporate sac obliteration.

Incidence, Prognostic Significance, and Risk Factors of Acute Kidney Injury Following Elective Infrarenal and Complex Endovascular Aneurysm Repair

Acute kidney injury (AKI) is a well known complication following cardiovascular procedures. The objective was to assess the incidence, risk factors, and prognostic significance of AKI after infrarenal endovascular aneurysm repair (EVAR) and complex EVAR (cEVAR; fenestrated or branched EVAR). Consecutive patients undergoing elective infrarenal EVAR or cEVAR between 2000 and 2018 in two large teaching hospitals in the Netherlands were included. AKI was determined by serum creatinine levels increasing > 1.5 times or by an absolute increase of 26.5 mmol/L from baseline value (KDIGO criteria). The primary outcome was incidence of peri-operative AKI development. Secondary outcomes included mid-term renal function (RIFLE criteria), overall survival, and risk factors for AKI development. To determine survival and risk factors for AKI, multivariable Cox regression and logistic regression analyses were performed, accounting for pre-operative renal function and other confounders. In total, 540 patients who underwent infrarenal EVAR with 147 patients who underwent cEVAR also included. The incidence of AKI was 8.7% (n= 47) in infrarenal EVAR patients and 23% (n= 34) in cEVAR patients (fenestrated EVAR 18%; branched EVAR 38%). In contrast to patients without AKI, the renal function of surviving patients with AKI remained significantly reduced at six weeks and did not return to pre-operative values following infrarenal EVAR (three year estimated glomerular filtration rate [eGFR] 59.3 ± 23.1 mL/min/1.73m2vs. pre-operative eGFR 74.0 ± 21.7 mL/min/1.73m2; p= .006) or following cEVAR (three year eGFR 52.0 ± 23.7 mL/min/1.73m2vs. pre-operative eGFR 65.4 ± 18.6 mL/min/1.73m2; p= .082). After risk adjusted analysis, compared with non-AKI, post-operative AKI development was associated with a higher three year mortality rate following both infrarenal and cEVAR (infrarenal EVAR mortality hazard ratio [HR 1.6, 95% confidence interval [CI] 1.01 - 2.7 [p= .046]; cEVAR mortality HR 2.4, 95% CI 1.1 - 5.2 [p= .033]). Following multivariable logistic regression, pre-operative chronic kidney disease (eGFR < 60 mL/min/1.73m2; odds ratio [OR] 2.2, 95% CI 1.03 - 4.8) and neck diameter (OR 1.1, 95% CI 1.01 - 1.2) were significantly associated with AKI following infrarenal EVAR, whereas for cEVAR only contrast volume (OR 1.1, 95% CI 1.0 - 1.2]) was found to be statistically significantly associated with AKI. AKI is a well described complication following infrarenal EVAR and is common after cEVAR. As AKI seems to be associated with permanent renal deterioration and lower survival, efforts to prevent AKI are essential. Future studies are required to assess what factors are associated with a higher risk of developing AKI following cEVAR.

Proximal seal dilatation following fenestrated endovascular repair for complex abdominal aortic aneurysms

Objective Although proximal neck dilatation following infrarenal endovascular aneurysm repair (EVAR) is common and is associated with proximal graft failure, little is known about sealing zone dilatation and its clinical relevance following fenestrated EVAR (FEVAR). We studied proximal seal dilatation (PSD) dynamics following FEVAR and assessed its clinical significance.

Inferior mesenteric artery diameter and number of patent lumbar arteries as factors associated with significant type 2 endoleak after infrarenal endovascular aneurysm repair.

OBJECTIVESOur goal was to identify the inferior mesenteric artery diameter and number of patent lumbar arteries causing a significant type 2 endoleak to develop after infrarenal endovascular aneurysm repair.MATERIAL AND METHODSIncluded were patients who underwent infrarenal endovascular aneurysm repair between April 2002 and January 2017. Patients with an aneurysm involving the iliac arteries were excluded. Significant type 2 endoleak was defined as a type 2 endoleak observed after infrarenal endovascular aneurysm repair and accompanied by abdominal aneurysm growth of at least 5 mm during that time.RESULTSA total of 277 patients were included. Mean follow-up was 38.9 (standard deviation 121.6) months. Immediately after infrarenal endovascular aneurysm repair, type 2 endoleaks occurred in 55 patients (20%), resolving spontaneously in 2 patients 6 months after infrarenal endovascular aneurysm repair. Thirty (10.8%) patients revealed a significant type 2 endoleak with aneurysm sack enlargement > 5 mm during follow-up, for which inferior mesenteric artery or lumbar artery coiling was performed. Mean time for coiling after primary infrarenal endovascular aneurysm repair was 25.4 (standard deviation 19.10) months. Twenty-three patients (8.3%) showed a non-significant type 2 endoleak during follow-up (no aneurysm sack enlargement). We found that the inferior mesenteric artery diameter and number of patent lumbar arteries were factors associated with a significant type 2 endoleak (odds ratio 1.755, P = 0.001; odds ratio 1.717, P < 0.001, respectively). Prior to endovascular aneurysm repair, the inferior mesenteric artery was patent in 212 (76.5%) patients; its median diameter measured 3 (0.5–3.8) mm. The median number of patent lumbar arteries was 3 (2–4). According to our receiver operating characteristic curve analysis, an inferior mesenteric artery diameter ≥3 mm (sensitivity 93.3%, specificity 65%) and ≥3 patent lumbar arteries (sensitivity 87.5%, specificity 43.6%) proved to be optimal cut-off values related to developing a significant type 2 endoleak. We therefore propose a composite score for the development of a significant type 2 endoleak [(inferior mesenteric artery diameter + patent lumbar arteries)/2].CONCLUSIONSPatients in whom the diameter of the inferior mesenteric artery is ≥ 3 mm and with ≥ 3 patent lumbar arteries carry a higher risk of developing significant type 2 endoleak after infrarenal endovascular aneurysm repair.

Significance of preoperative thrombus burden in the prediction of a persistent type II and reintervention after infrarenal endovascular aneurysm repair

BackgroundPersistent type II endoleak has necessitated prolonged surveillance and is a reason for reintervention after infrarenal endovascular aneurysm repair (EVAR). The aim of this study was to assess the association of thrombus burden (TB) within the aneurysmal sac in the prediction of a persistent type II endoleaks. MethodsConsecutive patients who underwent infrarenal EVAR from October 2009 to October 2017 in a single vascular network were included. TB was assessed on preoperative computed tomography angiogram and was defined as a percentage of thrombus across the maximal sac diameter in comparison with the luminal diameter measured orthogonally at the same level. Patients were categorized into three groups: low TB (<25%), medium TB (25%-50%), and high TB (>50%). All patients underwent postoperative EVAR surveillance comprising computed tomographic angiography or duplex ultrasound imaging. Type II endoleak observed for more than 1 year was defined as persistent type II endoleak. Odds ratio (OR) and Student’s t-test were used to determine significance. ResultsSome 275 EVARs were performed in the study period. A total of 45 procedures were excluded because of either iliac-only intervention (n = 9), no preoperative information (n = 7), abandoned (n = 1), or less than 1 year’s follow-up data (n = 28). For the 230 procedures included, the median follow-up was 43 (12-102) months. There were no significant differences between the groups for age, gender, and comorbidities nor preoperative sac diameter. There was high interobserver reliability with a kappa value of 0.89 (0.84-0.94) with a total discordance of 7% across the cohorts. Persistent type II endoleak occurred significantly more frequently with reduced TB: 41% of the low TB cohort compared with 4% of the high TB cohort (OR, 15.36 [3.5-67.3]; P = .0003). Reintervention was also significantly more likely to occur in the presence of a persistent type II endoleak compared with its absence; n = 12 of 13 (92%) patients who underwent reintervention had a persistent type II endoleak (OR, 43.4 [5.5-242]; P = .0003). Sac size reduction was significantly greater in medium TB and high TB cohorts when compared with low TB: −25% and −27% vs −15% (P = .0046 and P < .0001). Decreased TB was associated with a significant increase in inferior mesenteric artery (IMA) patency, the mean TB, where the IMA was patent, being 29% compared with 40% where the IMA was occluded P < .0001. When considered together, patients with a low TB and a patent IMA were even more likely to have a persistent type II endoleak when compared with those with a high TB and an occluded IMA (OR, 34.1 [1.99-583]; P = .015). ConclusionsLow TB is associated with increased rates of persistent type II endoleak, especially in the presence of a patent IMA. High TB is associated with increased sac regression and low reintervention rates. TB can be assessed reliably and could be used for risk stratification in the planning of infrarenal EVAR. Pre-emptive embolization of IMA or lumbar vessels in those with low TB may be beneficial. TB could be a useful tool for designing a post-EVAR surveillance regimen.

Proximal seal dilatation following fenestrated endovascular repair for complex abdominal aortic aneurysms

ObjectiveAlthough proximal neck dilatation following infrarenal endovascular aneurysm repair (EVAR) is common and is associated with proximal graft failure, little is known about sealing zone dilatation and its clinical relevance following fenestrated EVAR (FEVAR). We studied proximal seal dilatation (PSD) dynamics following FEVAR and assessed its clinical significance. MethodsWe included all consecutive patients treated for a juxta-/supra-renal aneurysm with fenestrated EVAR using the Zenith Fenestrated Endovascular Graft (Cook Medical, Bloomington, Ind) from 2008 to 2018 in two large teaching hospitals in the Netherlands. The primary outcome was PSD over time and was determined using a linear mixed-effects model. Secondary outcomes included associations for early PSD and difference in aortic dilatation at the level of the covered stent compared with the bare stent. Proximal seal-related adverse events were also obtained. ResultsOur cohort included 84 patients with a median computed tomography angiography follow-up time of 24.5 months (interquartile range [IQR], 17-42 months). Maximum aneurysm diameter was 60.1 mm (IQR, 56.9-67.2 mm). Mean proximal seal diameter at baseline was 26.2 mm (standard deviation [SD], ±2.8 mm), mean stent oversizing was 20.1% (SD, ±9.1%), and mean proximal seal length was 29.5 mm (SD, ±11.7 mm). Proximal seal dilatation of 1.7 mm (95% confidence interval [CI], 1.4-2.1 mm) was found in the first year, decelerating thereafter (second year, 0.9 mm/year; 95% CI, 0.7-1.1 mm/y). Over 10% PSD at 1 year occurred in 22 patients (27%) and was associated with stent graft oversizing (odds ratio, 1.1; 95% CI, 1.03-1.2; P = .008) and a lower number of target vessels (four fenestrations/ref two fenestrations: odds ratio, 0.13; 95% CI, 0.02-0.74; P = .029). At last available imaging, dilatation difference was higher at the level of the covered stent compared with the bare stent (3.0 mm [IQR, 1.3-5.1 mm] vs 1.6 mm [IQR, 0.8-2.5 mm]; P < .001). During the study period, only one patient (1.2%) developed a proximal seal-related adverse event (type IA endoleak). ConclusionsPSD is present following FEVAR, occurring at a faster rate in the first year and subsequently decelerating thereafter, similarly to neck dilatation after standard infrarenal EVAR. Although its clinical implication seems to remain limited in the first years following implantation, further research is required to assess the effect of PSD on long-term FEVAR outcomes.

Era of endovascular aortic aneurysm repair is linked to preoperative anatomic severity and perioperative patient outcomes

Varying opinions on optimal elective and emergent surgical management of infrarenal abdominal aortic aneurysms are expressed by the most recent Society for Vascular Surgery (SVS), European Society for Vascular Surgery, vs UK National Institutes for Health and Care Excellence guidelines. The UK National Institutes for Health and Care Excellence guidelines propose that open surgical repair serve as the default treatment for infrarenal abdominal aortic aneurysm. The rationale for this approach relied on data from the early era of endovascular aneurysm repair (EVAR) and are in contrast to the more balanced approaches of the SVS and European Society for Vascular Surgery. We hypothesize that significant differences in patient selection, management, and postoperative outcome are related to the era in which treatment was undertaken, contextualizing the outcomes reported in early-era EVAR randomized controlled trials. Retrospectively, two cohorts representing all EVAR patients from "early" (n= 167; 2008-2010) and "late" (n= 129; 2015-2017) periods at a single treating institution were assembled. Primary outcomes of era-related changes in preoperative demographics, anatomy, and intraoperative events were assessed; anatomy was compared using the SVS anatomic severity grading system. These era-related differences were then placed in the context of early perioperative outcomes and at follow-up to 1year. Choice of surgical strategy differed by era, despite the same patient preoperative comorbidities between EVAR groups. Preoperative anatomic severity was significantly worse in the early cohort (P< .001), with adverse proximal and distal seal zone features (P< .001). Technical success was 16.2% higher in the late cohort, with significantly fewer type 1A/B endoleaks perioperatively (P< .001). In-hospital complications, driven by higher acute kidney injury and surgical site complications in the early cohort, resulted in a 16.5% difference between cohorts (P< .05). At 1year of follow-up, outcome differences persisted; late-era patients had fewer 1A endoleaks, fewer graft complications, and better reintervention-free survival. From a granular dataset of EVAR patients, we found an impact of EVAR repair era on early clinical outcomes; late cohort infrarenal EVAR patients had less severe preoperative anatomy and improved perioperative and follow-up outcomes to 1year, suggesting that the results of early EVAR randomized controlled trials may no longer be generalizable to modern practice.

Intraoperative cone beam computed tomography to improve outcomes after infrarenal endovascular aortic repair

ObjectiveWe evaluated whether a combination of intraoperative contrast-enhanced cone beam computed tomography (ceCBCT) and postoperative contrast-enhanced ultrasound (CEUS) after infrarenal endovascular abdominal aortic aneurysm repair (EVAR) could reduce late stent graft–related complications and, consequently, reintervention. MethodsAll consecutive patients who had received infrarenal bifurcated stent grafts in our hybrid room (IGS 730; GE Healthcare, Île-de-France, France) during two discrete periods were included in the present study. From November 2012 to September 2013, two-dimensional completion angiography was performed after each EVAR, followed by computed tomography angiography (CTA) before discharge (group 1). From October 2013 to January 2015, intraoperative ceCBCT was performed, followed by CEUS within the first postoperative days (group 2). Comparative analyses of the outcomes were performed. The primary endpoint was late stent graft–related complications, a composite factor incorporating aneurysm-related death, type I or III endoleaks, kink or occlusion of the iliac limb, and aortic sac enlargement after the first 30 postoperative days. The secondary endpoint was all stent graft–related reinterventions. All-cause and aneurysm-related deaths were also recorded. ResultsOverall, 100 consecutive patients (50 each in groups 1 and 2) were enrolled, with a median follow-up of 60 months (interquartile range, 41-69 months). At 60 months after the index procedure, the freedom from late stent graft–related complications in each group was 61.6% (95% confidence interval [CI], 47.0%-80.6%) for group 1 and 81.7% (95% CI, 70.1%-95.2%) for group 2 (P = .033). The use of intraoperative ceCBCT was independently associated with a reduced rate of late stent graft–related complications on multivariate analysis (hazard ratio, 0.39; 95% CI, 0.16-0.95; P = .038) but did not appear to significantly protect against stent graft–related reinterventions (hazard ratio, 0.53; 95% CI, 0.20-1.39; P = .198) or all-cause death (P = .47). ConclusionsTo the best of our knowledge, the present study is the first to report the influence of routine ceCBCT on late outcomes after EVAR. The use of ceCBCT shows the potential for reducing late stent graft–related complications associated.

Predictors of Decline in Renal Function 5 Years after EVAR.

While there exists copious short-term data regarding renal function following infra-renal endovascular abdominal aortic aneurysm repair (EVAR), long-term analysis is sparse. This is a single institution retrospective review of predictors of renal function decline 5 years after elective EVAR. All EVAR between 2007 and 2015 were queried. Patients in whom renal function was documented 5 years postoperatively were included in analysis. Exclusion criteria were ruptured aneurysm, mortality before 56 months, lack of follow-up, ESRD status, and concomitant renal intervention. The primary outcome investigated was a 20% or greater drop in glomerular filtration rate (GFR) 5 years postoperatively. The following variables at the time of surgery were investigated as potential predictors: age, gender, hypertension, hyperlipidemia, diabetes, CAD or prior MI, COPD, prior stroke, baseline eGFR under 60mL/min/1.73m2, supra-renal fixation, infra-renal fixation, neck diameter, neck length, and number of contrast CT. 354 EVAR were identified of which 143 met inclusion criteria (211 excluded). Univariate analysis revealed female gender (OR 2.7), hypertension (OR 9.4), baseline renal insufficiency (OR 3.8), larger neck diameter, and supra-renal fixation (OR 2.32) all predictive (P < .05) of GFR drop at 5 years. Multivariate binary logistic regression analysis found female gender (multivariate OR 3.9, P = .023) and baseline renal insufficiency (multivariate OR 3.0, P = .029) as significant predictors of greater than 20% GFR drop at 5 years. Only 2 patients of the 143 progressed to dialysis requirement at 5 years. Females and patients with baseline renal insufficiency are more vulnerable to significant decline in renal function 5 years following EVAR. Consistent with analogous literature, supra-renal fixation appears moderately deleterious toward renal function with no clinical significance in those with baseline normal renal function. The potential benefit of avoidance of supra-renal fixation in female patients with baseline renal insufficiency is worth further investigation in a more robust multi-center study.

Solitary iliac branch endoprosthesis placement for iliac artery aneurysms

BackgroundIsolated iliac artery aneurysms (IAAs), accounting for 2% to 7% of all abdominal aneurysms, are often treated with the use of iliac branched endografts. Although outside the manufacturer's instructions for use, iliac branched devices can be used solely, without the adjunctive placement of an endovascular aneurysm repair device, for the treatment of an isolated IAA. In the present study, we have described the outcomes of the use of the Gore iliac branched endoprosthesis (IBE; W.L. Gore & Associates, Flagstaff, Ariz), without the support of an infrarenal endovascular aneurysm repair device, for the exclusion of an isolated IAA. The present study was an international multicenter retrospective cohort analysis. MethodsAll the patients who had undergone treatment with a solitary IBE for IAA exclusion from January 11, 2013 to December 31, 2018 were retrospectively reviewed. The primary outcome was technical success. The secondary outcomes included mortality, intraoperative and postoperative complications, and reintervention. ResultsA total of 18 European and American centers participated, with a total of 51 patients in whom 54 IAAs were excluded. The technical success rate was 94.1%, with an assisted technical success rate of 96.1%. No 30-day mortality occurred, with 98.1% patency of the internal and external iliac artery found at 24 months of follow-up. At 24 months of follow-up, 81.5% of the patients were free of complications and 90% were free of a secondary intervention. ConclusionsTreatment with a solitary IBE is a safe and, at midterm, an effective treatment strategy for selected patients with a solitary IAA.

Female Gender: A Leading Predictor of Decline in Renal Function 5 Years After Endovascular Abdominal Aortic Aneurysm Repair

Although copious short-term data exist regarding renal function after infrarenal endovascular abdominal aortic aneurysm repair (EVAR), long-term data are sparse. We performed a single-institution retrospective review to identify the predictors of renal function 5 years after elective EVAR. All EVAR cases performed at a single institution from 2007 to 2015 were queried. Patients for whom renal function was documented 5 years postoperatively were included in present analysis. The exclusion criteria were ruptured aneurysms, mortality before 56 months, lack of follow-up, end-stage renal disease status, and concomitant renal intervention. The primary outcome was a ≥20% decrease in the glomerular filtration rate (GFR) at 5 years postoperatively. The following variables at surgery were investigated as potential predictors: age, gender, hypertension, hyperlipidemia, diabetes, coronary artery disease or prior myocardial infarction, chronic obstructive pulmonary disease, prior stroke, baseline estimated GFR <60 mL/min/1.73 m2, suprarenal fixation, infrarenal fixation, neck diameter, neck length, and number of contrast computed tomography scans. A total of 354 EVARs were identified, of which 143 met the inclusion criteria (211 were excluded). Univariate analysis revealed that female gender, hypertension, baseline renal insufficiency, larger neck diameter, and suprarenal fixation (relative to infrarenal fixation) were all predictive (P < .05) of a GFR decrease at 5 years postoperatively. Multivariate binary logistic regression analysis found female gender and baseline renal insufficiency were significant predictors (P = .02 for both) of a >20% GFR decrease at 5 years (Table). Only 2 of the 143 patients in the present study had required to dialysis at 5 years. Women and patients with baseline renal insufficiency are more vulnerable to a significant decline in renal function at 5 years after EVAR. Consistent with analogous literature, suprarenal fixation appeared moderately deleterious toward renal function. The potential benefit of avoiding suprarenal fixation in female patients with baseline renal insufficiency is worth further investigation in a more robust multicenter study.Tabled 1Table. Predictors of greater than 20% drop in GFR 5 years after EVARVariableGreater than 20% drop in GFR at 5 years (n = 32)No drop in GFR >20% at 5 Years postop (n = 111)Univariate odds ratioUnivariate P valueMultivariate odds ratio (95% CI)Multivariate P valueFemale gender28% (n = 9)13% (n = 14)2.7.0353.9 (1.2-12.3).023Male gender72% (n = 23)87% (n = 97)Mean age75.25 (SD 7.6)72.6 (SD 8.28).1.351Diabetes mellitus25% (n = 8)30% (n = 33)0.78.61.3 (0.5-3.7).552Hypertension97% (n = 31)77% (n = 85)9.4.015.0 (0.5-50.3).172Hyperlipidemia84% (n = 26)70% (n = 78)1.3.222.2 (.64-7.4).211COPD16% (n = 5)11% (n = 17)1.02.970.8 (.22-.79).733CAD or Hx of MI56% (n = 18)60% (n = 67)0.84.681.4 ( .54-3.5).497Hx of prior stroke13% (n = 5)11% (n = 12)1.52.461.5 (.31-7.3)0.61Baseline eGFR less than 6050% (n = 16)21% (n = 23)3.8.0013.0 (1.1-7.9).029Mean neck diameter, mm28.3 (SD 4.08)24.1 (SD 3.87)<.001.825Mean neck length, mm28.3 (SD 12.3)31.67 (SD 14).22.491Mean number contrast CT Scan at 5 years postop3.4 (SD 2.56)4.74 (SD 3.48).95.356Suprarenal fixation69% (n = 22)49% (n = 54)2.32.042.2 (.83-5.6).102Infrarenal fixation31% (n = 10)51% (n = 57)Nominal Variables : Chi-Squared Test for UnivariateOrdinal Variables : T-test for UnivariateMultivariate Analysis : Binary Logistic Regression Analysis Open table in a new tab

Survival and durability after endovascular aneurysm repair reflect era-related surgical judgement

ObjectiveAbdominal aortic aneurysm management guidelines from the National Institute for Clinical Excellence in 2020, based heavily on randomized controlled trials in an early era of infrarenal endovascular aneurysm repair (EVAR), suggested that the long-term outcomes after EVAR jeopardize its use in elective abdominal aortic aneurysm repair. We hypothesized that, in a rapidly evolving surgical field, the era of aneurysm repair may have a significant influence on long-term patient outcomes. MethodsUsing a single-center retrospective cohort design, we identified two EVAR cohorts, the early cohort (n = 166) who underwent EVAR from 2008 to 2010, and a contemporary late cohort (n = 129) from 2015 to 2017. We assessed patient preoperative demographics and era of repair against the primary outcomes of reinterventions, reintervention-free survival, and mortality, addressing their relationships to anatomic selection criteria, graft durability, endoleak, and aneurysm diameter to 5 years after the procedure. ResultsEarly cohort patients had decreased reintervention-free survival (early 80.1% vs late 93.3%) and decreased overall survival (early 71.3% vs late 81%) at 3 years and throughout follow-up. The preoperative anatomy judged suitable for EVAR in early cohort patients was more variable than for late cohort patients, including 104% larger proximal and 106% larger distal landing zone diameters, with a mean 11.6-mm shorter length infrarenal aortic and 13.3-mm shorter length iliac sealing zones in the early group. Early cohort patients had more complications during follow-up, including graft kinking and endoleaks, and 24.4% of early vs 8.5% of late patients underwent one or more reinterventions. ConclusionsAlthough technical skill in EVAR implantation may not evolve significantly after a threshold of cases, surgical judgement, relating to anatomic selection and device sizing, requires feedback from long-term sequalae and significantly impacted EVAR outcomes by era. EVAR patients from an early repair era had significantly worse outcomes, with more complications, reinterventions, and a decrease in survival.

A Comparison of Computed Tomography Angiography and Colour Duplex Ultrasound Surveillance Post Infrarenal Endovascular Aortic Aneurysm Repair: Financial Implications and Impact of Different International Surveillance Guidelines

Use of colour duplex ultrasound (CDUS) and computed tomography angiography (CTA) for infrarenal endovascular aortic aneurysm repair (EVAR) surveillance differs in internationally published guidelines. This study aimed firstly to compare CDUS detection of significant sac abnormalities with CTA. Secondly, a sensitivity analysis was conducted to compare financial estimates of the, predominantly CDUS based, local and Society of Vascular Surgery (SVS) protocols, the risk stratified European Society of Vascular Surgery (ESVS) protocol, and the CTA based National Institute of Health and Care Excellence (NICE) protocol.

Simple diameter measurements with ultrasound can be safely used to follow the majority of patients after infrarenal endovascular aneurysm repair

The optimal imaging follow-up after infrarenal EVAR is still undefined. The aim of this study was to analyze the outcome of a personalized follow-up program after infrarenal EVAR based on ultrasound AAA diameter measurements for low-risk patients.All consecutive patients followed-up locally after elective and acute infrarenal EVAR between 2010 and 2015 were retrospectively reviewed. Patients underwent CTA at 1-month post-EVAR whereby the attending surgeon defined the subsequent follow-up. Patients considered at low risk were followed with ultrasound only assessing AAA diameter at 1, 2, 3 and every 5 years postoperatively (group A). Low risk required a favorable pre-operative anatomy especially regarding the aneurysm neck, satisfactory intraoperative result and uneventful 1 month CTA (type 2 endoleaks acceptable). Patients not fulfilling the criteria for group A were followed with yearly 3-phase-CTAs (group B).Two hundred twenty-two patients with a AAA median diameter of 58 (54-68) mm were included. One hundred ninety-one were allocated into group A and 31 in group B. Median follow-up time was 36 (24-59) months. Five-year primary and primary-assisted success was 82±5% and 93±3% for group A and 70±13% and 93±5% for group B, respectively (P=0.042 and P=0.504, respectively). Sixteen late aneurysm-related reinterventions were performed in 12 patients (7 in group A and 9 in group B). In group A, 5 reinterventions were rupture-preventing and 2 were symptomatic. All late reinterventions in group B were performed following findings on follow-up imaging. Five-year late reintervention-free survival was 95±2% and 84±7% for groups A and B, respectively (P=0.046). Five-year survival was 80±3% and 63±10% for group A and B, respectively (P=0.024).A customized follow-up program after infrarenal EVAR based on ultrasound AAA diameter measurements in low-risk patients seems to be effective in maintaining a very high mid-term clinical success rate.

Editor's Choice – A Comparison of Computed Tomography Angiography and Colour Duplex Ultrasound Surveillance Post Infrarenal Endovascular Aortic Aneurysm Repair: Financial Implications and Impact of Different International Surveillance Guidelines

Use of colour duplex ultrasound (CDUS) and computed tomography angiography (CTA) for infrarenal endovascular aortic aneurysm repair (EVAR) surveillance differs in internationally published guidelines. This study aimed firstly to compare CDUS detection of significant sac abnormalities with CTA. Secondly, a sensitivity analysis was conducted to compare financial estimates of the, predominantly CDUS based, local and Society of Vascular Surgery (SVS) protocols, the risk stratified European Society of Vascular Surgery (ESVS) protocol, and the CTA based National Institute of Health and Care Excellence (NICE) protocol. Agreement between CDUS and CTA was assessed for detection of significant sac abnormalities. Surveillance protocols were extrapolated from published guidelines and applied to infrarenal EVAR patients active on local surveillance at a large, single centre. Surveillance intensity was dependent on presence of endoleak and subsequent risk of treatment failure in accordance with surveillance recommendations. Estimates for each surveillance protocol were inclusive of a range of published incidences of endoleak, contrast associated acute kidney injury (AKI), and excess hospital bed days, and estimated for a hypothetical five year surveillance period. The kappa coefficient between CDUS and CTA for detecting sac abnormalities was 0.68. Maximum five year surveillance cost estimates for the 289 active EVAR patients were £272 359 for SVS, £230 708 for ESVS, £643 802 for NICE, and £266 777 for local protocols, or £1 270, £1 076, £3 003, and £1 244 per patient. Differences in endoleak incidence accounted for a 1.1 to 1.4 fold increase in costs. AKI incidence accounted for a 3.3 to 6.2 fold increase in costs. A combined CTA and CDUS EVAR surveillance protocol, with CTA reserved for early seal assessment and confirmatory purposes, provides an economical approach without compromising detection of sac abnormalities. AKI, as opposed to direct imaging costs, accounted for the largest differences in surveillance cost estimates.

Sex-related outcomes after fenestrated-branched endovascular aneurysm repair for thoracoabdominal aortic aneurysms in the U.S. Fenestrated and Branched Aortic Research Consortium

ObjectiveFenestrated-branched endovascular aneurysm repair (FBEVAR) has expanded the treatment of patients with thoracoabdominal aortic aneurysms (TAAAs). Previous studies have demonstrated that women are less likely to be treated with standard infrarenal endovascular aneurysm repair because of anatomic ineligibility and experience greater mortality after both infrarenal and thoracic aortic aneurysm repair. The purpose of the present study was to describe the sex-related outcomes after FBEVAR for treatment of TAAAs. MethodsThe data from 886 patients with extent I to IV TAAAs (excluding pararenal or juxtarenal aneurysms), enrolled in eight prospective, physician-sponsored, investigational device exemption studies from 2013 to 2019, were analyzed. All data were collected prospectively, audited and adjudicated by clinical events committees and/or data safety monitoring boards, and subject to Food and Drug Administration oversight. All the patients had been treated with Cook-manufactured patient-specific FBEVAR devices or the Cook t-Branch off-the-shelf device (Cook Medical, Brisbane, Australia). ResultsOf the 886 patients who underwent FBEVAR, 288 (33%) were women. The women had more extensive aneurysms and a greater prevalence of diabetes (33% vs 26%; P = .043) but a lower prevalence of coronary artery disease (33% vs 52%; P < .0001) and previous infrarenal endovascular aneurysm repair (7.6% vs 16%; P < .001). The women had required a longer operative time from incision to surgery end (5.0 ± 1.8 hours vs 4.6 ± 1.7 hours; P < .001), experienced lower technical success (93% vs 98%; P = .002), and were less likely to be discharged to home (72% vs 83%; P = .009). Despite the smaller access vessels, the women did not have an increased incidence of access site complications. Also, the 30-day outcomes were broadly similar between the sexes. At 1 year, no differences were found between the women and men in freedom from type I or III endoleak (91.4% vs 92.0%; P = .64), freedom from reintervention (81.7% vs 85.3%; P = .10), target vessel instability (87.5% vs 89.2%; P = .31), and survival (89.6% vs 91.7%; P = .26). The women had a greater incidence of postoperative sac expansion (12% vs 6.5%; P = .006). Multivariable modeling adjusted for age, aneurysm extent, aneurysm size, urgent procedure, and renal function showed that patient sex was not an independent predictor of survival (hazard ratio, 0.83; 95% confidence interval, 0.50-1.37; P = .46). ConclusionsWomen undergoing FBEVAR demonstrated metrics of increased complexity and had a lower level of technical success, especially those with extensive aneurysms. Compared with the men, the women had similar 30-day mortality and 1-year outcomes, with the exception of an increased incidence of sac expansion. These data have demonstrated that FBEVAR is safe and effective for women and men but that further efforts to improve outcome parity are indicated.