Infrarenal Endovascular Aneurysm Repair Research Articles

Delayed open conversion after endovascular aortic repair.

We present the clinical outcomes of patients who underwent delayed (>30 days) open surgical repair after endovascular aortic aneurysm repair. All patients receiving delayed open repair of infrarenal and juxtarenal aortic aneurysms after endovascular repair from July 2001 to December 2017 were retrospectively reviewed. Patients' baseline characteristics, indications for delayed open conversion, and time between endovascular repair and open conversion are described. Early outcomes included operative approach, morbidity, and mortality. Midterm outcomes included survival. Twenty-two (3.3%) of 667 patients with prior infrarenal endovascular aortic aneurysm repair had delayed open conversion (20 elective and 2 emergency). The time from endovascular repair to open conversion was 60 ± 36 months. The indications were 6 (27%) type Ia endoleaks, 6 (27%) type II endoleaks with enlarging sac size, 2 (9%) endotensions, 7 (32%) unknown types of endoleak, and 1 (5%) graft infection. The 7 minutes unknown endoleaks were confirmed as lumbar leaks in 4 cases and fabric leaks in 3. Operative time was 222 ± 48 min with blood loss of 2211 ± 2057 mL. Hospital stay after conversion was 12 ± 8 days. There was no 30-day mortality. Estimated survival rates were 96%, 91%, 86%, 79% and 57% at 1, 2, 3, 4, and 5 years postoperatively. Delayed conversion to open surgery after endovascular aortic aneurysm repair by endograft explantation appears to be safe with good short- and mid-term outcomes. With careful preoperative assessment, open conversion remained a realistic and viable option in patients with failed endovascular treatment.

Fenestrated endovascular aneurysm repair is associated with lower perioperative morbidity and mortality compared with open repair for complex abdominal aortic aneurysms

ObjectiveThe Zenith Fenestrated Endovascular Graft (ZFEN; Cook Medical, Bloomington, Ind) has expanded the anatomic eligibility of endovascular aneurysm repair (EVAR) for complex abdominal aortic aneurysms (AAAs). Current data on ZFEN mainly consist of single-institution experiences and show conflicting results. Therefore, we compared perioperative outcomes after repair using ZFEN with open complex AAA repair and infrarenal EVAR in a nationwide multicenter registry. MethodsWe identified all patients undergoing elective AAA repair using ZFEN, open complex AAA repair, and standard infrarenal EVAR between 2012 and 2016 within the American College of Surgeons National Surgical Quality Improvement Program targeted vascular module. Open complex AAA repairs were defined as those with a juxtarenal or suprarenal proximal AAA extent in combination with an aortic cross-clamping position that was above at least one renal artery. The primary outcome was perioperative mortality, defined as death within 30 days or within the index hospitalization. Secondary outcomes included postoperative renal dysfunction (creatinine concentration increase of >2 mg/dL from preoperative value or new dialysis), occurrence of any complication, procedure times, blood transfusion rates, and length of stay. To account for baseline differences, we calculated propensity scores and employed inverse probability-weighted logistic regression. ResultsWe identified 6825 AAA repairs—220 ZFENs, 181 open complex AAA repairs, and 6424 infrarenal EVARs. Univariate analysis of ZFEN compared with open complex AAA repair demonstrated lower rates of perioperative mortality (1.8% vs 8.8%; P = .001), postoperative renal dysfunction (1.4% vs 7.7%; P = .002), and overall complications (11% vs 33%; P < .001). In addition, fewer patients undergoing ZFEN received blood transfusions (22% vs 73%; P < .001), and median length of stay was shorter (2 vs 7 days; P < .001). After adjustment, open complex AAA repair was associated with higher odds of perioperative mortality (odds ratio [OR], 4.9; 95% confidence interval [CI], 1.4-18), postoperative renal dysfunction (OR, 13; 95% CI, 3.6-49), and overall complication rates (OR, 4.2; 95% CI, 2.3-7.5) compared with ZFEN. Compared with infrarenal EVAR, ZFEN presented comparable rates of perioperative mortality (1.8% vs 0.8%; P = .084), renal dysfunction (1.4% vs 0.7%; P = .19), and any complication (11% vs 7.7%; P = .09). Furthermore, after adjustment, there was no significant difference between the odds of perioperative mortality, postoperative renal dysfunction, or any complication between infrarenal EVAR and ZFEN. ConclusionsZFEN is associated with lower perioperative morbidity and mortality compared with open complex AAA repair, and outcomes are comparable to those of infrarenal EVAR. Long-term durability of ZFEN compared with open complex AAA repair warrants future research.

Preservation of the Inferior Mesenteric Artery With a Surgeon-customised Fenestration

Abdominal aortic aneurysms (AAA) are most frequently treated by endovascular aneurysm repair (EVAR). A recognised drawback of EVAR is loss of the inferior mesenteric artery (IMA), which when associated with the additional occlusion of both hypogastric arteries, puts the patient at risk of ischaemic colitis or pelvic ischaemia. A surgeon-customised fenestration technique used in a 70 year old man with an AAA, occluded hypogastric arteries, and a large IMA is described. The diameter of the IMA, distance to the lower renal artery, and clock face positions were assessed with TeraRecon software (TeraRecon Foster City, CA, USA). The main body of an Endurant stent graft (Medtronic, Dublin, Ireland) was partially unsheathed. The location and shape of the fenestration was drawn on the graft between two rows of stent. A 6 mm fenestration was created by using a 1205 °C cautery loop tip (Accu-Temp; Beaver-Visitec International, Waltham, MA, USA). To prevent the burning of the polyester, the graft was continuously irrigated with cold isotonic saline. A segment of a 25 mm Amplatz goose neck snare (Medtronic) was sutured around the fenestration with a polytetrafluoroethylene monofilament suture (CV-5 Gore-Tex; WL Gore & Associates, Flagstaff, AZ, USA) to serve as a radio-opaque marker (Fig. 1A). The graft was then re-sheathed by using a silicone rubber band tightly wrapped around the graft and loosened gradually when the sheath came over (Fig. 1B). Once the stent graft was deployed, the fenestration and the IMA were catheterised with a SIM1 catheter and a 7 × 22 mm covered stent (Advanta V12; Maquet, Sunderland, UK) (Fig. 2A and B) was subsequently deployed and flared with a 9 × 20 mm angioplasty balloon.Figure 2(A) Catheterisation of the inferior mesenteric artery by surgeon-customised fenestration. (B) Post-operative three dimensional reconstruction showing patency of the fenestration and occlusion of both hypogastric arteries.View Large Image Figure ViewerDownload Hi-res image Download (PPT) Surgeon-customised fenestration is a straightforward technique that provides an option for maintaining IMA patency in patients at risk of ischaemic colitis and pelvic ischaemia following infrarenal EVAR.

Endovascular Aneurysm Repair Complicated with Type Ia Endoleak and Presumable Infection Treated with a Fenestrated Endograft.

An 81-year-old patient presented to the emergency room 5 years after infrarenal endovascular aneurysm repair, with a Type Ia endoleak and a presumable infection of the graft material with Listeria monocytogenes . He was treated with a custom-made fenestrated endograft to seal the endoleak and lifelong antibiotic therapy to suppress the infection. Full explantation of graft material is not always preferable, and endovascular treatment combined with antibiotic suppressive therapy is in some cases an appropriate alternative.

Laparoscopic ligation of Type II endoleaks following endovascular aneurysm repair: A systematic review.

The clinical significance of Type II endoleak remains contentious; the strategies used for its management have continued to expand. We systematically review the literature and comprehensively appraise the effectiveness of laparoscopic intervention in the management of this common complication. A systematic search was performed in accordance to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines on MEDLINE, EMBASE and Cochrane Library for relevant articles reporting laparoscopic surgery of Type II endoleak post-endovascular aortic repair. Thirteen studies representing 40 patients were investigated. Mean age was 72.7 years, and proportion of males was 90.0%. All patients were American Society of Anesthesiologists grade II and above and underwent standard infrarenal endovascular aneurysm repair. The mean duration of operation was 130.2 min, with a mean blood loss across of 173.8 mL. The overall technical success rate was 90% (27/30). Two patients required reoperation within 24 h, with further lumbar ligations that were successful. One other patient required conversion to open surgery due to significant bleeding at the dorsal aorta. The perioperative and 30-day mortality rate was 2.5% (1/40). The mean length of hospital stay was 3.7 days (range 1 to 10 days). The mean length of follow-up was 36.7 months (range 3 to 103.2 months), where the rate of recurrence was 22.5% (9/40). Laparoscopic ligation of feeding vessels causing Type II endoleak is potentially an alternative treatment after failed standard endovascular embolization, particularly in select centres with necessary resources and capabilities.

Complex endovascular aneurysm repair is associated with higher perioperative mortality but not late mortality compared with infrarenal endovascular aneurysm repair among octogenarians

ObjectiveAs our collective experience with complex endovascular aneurysm repair (EVAR) has grown, an increasing number of older patients are being offered endovascular repair of juxtarenal aneurysms. Outcomes after complex EVAR in this older subpopulation are not well-described. We sought to specifically evaluate clinical outcomes after complex EVAR compared with infrarenal EVAR in a cohort of octogenarians. MethodsA single-center retrospective review was conducted using a database of consecutive patients treated with elective EVAR for abdominal aortic aneurysms (AAAs) between 2009 and 2015. Only patients 80 years of age or older were included. Patients in the complex EVAR group were treated with either snorkel/chimney or fenestrated techniques, whereas infrarenal EVAR consisted of aneurysm repair without renal or visceral involvement. Relevant demographic, anatomic, and device variables, and clinical outcomes were collected. ResultsThere were 103 patients (68 infrarenal, 35 complex) treated within the study period with a mean follow-up of 21 months. A total of 75 branch grafts were placed (59 renal, 11 celiac, 5 superior mesenteric artery) in the complex group, with a target vessel patency of 98.2% at latest follow-up. Patients undergoing complex EVAR were more likely to be male (82.8% vs 60.2%; P = .02) and have a higher prevalence of renal insufficiency (71.4% vs 44.2%; P = .008). The 30-day mortality was significantly greater in patients treated with complex EVAR (8.6% vs 0%; P = .03). There were no differences in major adverse events (P = .795) or late reintervention (P = .232) between groups. Interestingly, sac growth of more than 10 mm was noted to be more frequent with infrarenal EVAR (17.6% vs 2.8%; P = .039). However, both type IA (5.7% infrarenal; 4.9% complex) and type II endoleaks (32.3% infrarenal; 25.7% complex) were found to be equally common in both groups. Complex EVAR was not associated with increased all-cause mortality at latest follow-up (P = .322). Multivariable Cox modeling demonstrated that AAAs greater than 75 mm in diameter (hazard ratio; 4.9; 95% confidence interval, 4.6-48.2) and renal insufficiency (hazard ratio, 3.71; 95% confidence interval, 1.17-11.6) were the only independent risk factors of late death. ConclusionsComplex EVAR is associated with greater perioperative mortality compared with infrarenal EVAR among octogenarians. However, late outcomes, including the need for reintervention and all-cause mortality, are not significantly different. Larger aneurysms and chronic kidney disease portends greater risk of late death after EVAR, regardless of AAA complexity. These patient-related factors should be considered when offering endovascular treatment to older patients.

Infrarenal endovascular aneurysm repair with large device (34- to 36-mm) diameters is associated with higher risk of proximal fixation failure

ObjectiveEndovascular aneurysm repair (EVAR) has become the standard of care for infrarenal aneurysms. Endografts are commercially available in proximal diameters up to 36 mm, allowing proximal seal in necks up to 32 mm. We sought to further investigate clinical outcomes after standard EVAR in patients requiring large main body devices. MethodsWe performed a retrospective review of a prospectively maintained database for all patients undergoing elective EVAR for infrarenal abdominal aortic aneurysms at a single institution from 2000 to 2016. Only endografts with the option of a 34- to 36-mm proximal diameter were included. Requisite patient demographics, anatomic and device-related variables, and relevant clinical outcomes and imaging were reviewed. The primary outcome in this study was proximal fixation failure, which was a composite of type IA endoleak and stent graft migration >10 mm after EVAR. Outcomes were stratified by device diameter for the large-diameter device cohort (34-36 mm) and the normal-diameter device cohort (<34 mm). ResultsThere were 500 patients treated with EVAR who met the inclusion criteria. A total of 108 (21.6%) patients received large-diameter devices. There was no difference between the large-diameter cohort and the normal-diameter cohort in terms of 30-day (0.9% vs 0.95%; P = .960) or 1-year mortality (9.0% vs 6.2%; P = .920). Proximal fixation failure occurred in 24 of 392 (6.1%) patients in the normal-diameter cohort and 26 of 108 (24%) patients in the large-diameter cohort (P < .001). There were 13 (3.3%) type IA endoleaks in the normal-diameter cohort and 16 (14.8%) in the large-diameter cohort (P < .001). Stent graft migration (>10 mm) occurred in 15 (3.8%) in the normal-diameter cohort and 16 (14.8%) in the large-diameter cohort (P < .001). After multivariate analysis, only the use of Talent (Medtronic, Minneapolis, Minn) endografts (odds ratio [OR], 4.50; 95% confidence interval [CI], 1.18-17.21) and neck diameter ≥29 mm (OR, 2.50; 95% CI, 1.12-5.08) remained significant independent risk factors for development of proximal fixation failure (OR, 3.99; 95% CI, 1.75-9.11). ConclusionsStandard EVAR in patients with large infrarenal necks ≥29 mm requiring a 34- to 36-mm-diameter endograft is independently associated with an increased rate of proximal fixation failure. This group of patients should be considered for more proximal seal strategies with fenestrated or branched devices vs open repair. Also, this group likely needs more stringent radiographic follow-up.

Financial implications of coding inaccuracies in patients undergoing elective endovascular abdominal aortic aneurysm repair

ObjectivePrevious cost analyses have found small to negative margins between hospitalization cost and reimbursement for endovascular aneurysm repair (EVAR). Hospitals obtain reimbursement on the basis of Medicare Severity Diagnosis Related Group (MS-DRG) coding to distinguish patient encounters with or without major comorbidity or complication (MCC). This study's objective was to evaluate coding accuracy and its effect on hospital cost for patients undergoing EVAR. MethodsA retrospective, single university hospital review of all elective, infrarenal EVARs performed from 2010 to 2015 was completed. Index procedure hospitalizations were reviewed for MS-DRG classification, comorbidities, complications, length of stay (LOS), and hospitalization cost. Patients' comorbidities and postoperative complications were tabulated to verify accuracy of MS-DRG classification. Misclassified patients were audited and reclassified as “standard” or “complex” on the basis of a corrected MS-DRG: standard for 238 (major cardiovascular procedure without MCC) and complex for 237 (major cardiovascular procedure with MCC). ResultsThere were 104 EVARs identified, including 91 standard (original MS-DRG 238, n = 85; MS-DRG 254, n = 6) and 13 complex hospitalizations (original MS-DRG 237, n = 9; MS-DRG 238, n = 3; MS-DRG 253, n = 1). On review, 3% (n = 3) of the originally assigned MS-DRG 238 patients were undercoded while actually meeting MCC criteria for a 237 designation. Hospitalizations coded with MS-DRG 253 and 254 were considered billing errors because MS-DRG 237 and 238 are more appropriate and specific classifications as major cardiovascular procedures. Overall, there was a 9.6% miscoding rate (n = 10), representing a total lost billing opportunity of $587,799. Mean LOS for standard and complex hospitalizations was 3.0 ± 1.5 days vs 7.8 ± 6.0 days (P < .001), with respective intensive care unit LOS of 0.4 ± 0.7 day vs 2.6 ± 3.1 days (P < .001). Postoperative complications occurred in 23% of patients; however, not all met the Centers for Medicare and Medicaid Services criteria as MCC. Miscoded complexity was found to be due to postoperative events in all patients rather than to missed comorbidities. Mean hospitalization cost for standard and complex patients was $28,833 ± $5597 vs $41,543 ± $12,943 (P < .001). Based on institutional reimbursement data, this translates to a mean loss of $5407 per correctly coded patient. Miscoded patients represent an additional overall reimbursement loss of $140,102. ConclusionsOur study reveals a large lost billing opportunity with miscoding of elective EVARs from 2010 to 2015, with errors in categorization of the procedure as well as miscoding of complexity. The revenue impact is potentially significant in this population, and additional reviews of coding practices should be considered.

The Implications of Non-compliance to Endovascular Aneurysm Repair Surveillance: A Systematic Review and Meta-analysis

Increasingly, reports show that compliance rates with endovascular aneurysm repair (EVAR) surveillance are often suboptimal. The aim of this study was to determine the safety implications of non-compliance with surveillance. The study was carried out according to the Preferred Items for Reporting of Systematic Reviews and Meta-Analyses (PRISMA) guidelines. An electronic search was undertaken by two independent authors using Embase, MEDLINE, Cochrane, and Web of Science databases from 1990 to July 2017. Only studies that analysed infrarenal EVAR and had a definition of non-compliance described as weeks or months without imaging surveillance were analysed. Meta-analysis was carried out using the random-effects model and restricted maximum likelihood estimation. Thirteen articles (40,730 patients) were eligible for systematic review; of these, seven studies (14,311 patients) were appropriate for comparative meta-analyses of mortality rates. Three studies (8316 patients) were eligible for the comparative meta-analyses of re-intervention rates after EVAR and four studies (12,995 patients) eligible for meta-analysis for abdominal aortic aneurysm related mortality (ARM). The estimated average non-compliance rate was 42.0% (95% confidence interval [CI] 28-56%). Although there is some evidence that non-compliant patients have better survival rates, there was no statistically significant difference in all cause mortality rates (year 1: odds ratio [OR] 5.77, 95% CI 0.74-45.14; year 3: OR 2.28, 95% CI 0.92-5.66; year 5: OR 1.81, 95% CI 0.88-3.74) and ARM (OR 1.47, 95% CI 0.99-2.19) between compliant and non-compliant patients in the first 5 years after EVAR. The re-intervention rate was statistically significantly higher in compliant patients from 3 to 5 years after EVAR (year 1: OR 6.36, 95% CI 0.23-172.73; year 3: OR 3.94, 85% CI 1.46-10.69) year 5: OR 5.34, 95% CI 1.87-15.29). This systematic review and meta-analysis suggest that patients compliant with EVAR surveillance programmes may have an increased re-intervention rate but do not appear to have better survival rates than non-compliant patients.

Update on the status of infrarenal AAA devices.

There are a variety of endografts currently available for endovascular repair of abdominal aortic aneurysms. Aneurysms of increasing anatomic complexity are being repaired with devices that are either newly approved or redesigned relative to the initial published experience with infrarenal endovascular aortic aneurysm repair (EVAR). This article describes the contemporary devices approved for infrarenal EVAR in the United States and includes an up-to-date compilation of the data addressing outcomes specific to each device.

Select early type IA endoleaks after endovascular aneurysm repair will resolve without secondary intervention

ObjectiveAlthough it is traditionally considered ominous, the natural history of early proximal attachment site endoleaks (IA) after endovascular aneurysm repair (EVAR) is not well known. Our aim was to identify risk factors for persistent type IA endoleaks and to determine their effect on long-term outcomes after EVAR. MethodsAll patients who underwent infrarenal EVAR at a single institution between 1998 and 2015 were identified. Preoperative axial imaging and intraoperative arteriograms were reviewed, and those patients with a type IA endoleak were further studied. Aneurysm features were characterized by two reviewers and were studied for predictors of persistent endoleaks at the conclusion of the case. Patient records and the Social Security Death Index were used to record 1-year and overall survival. ResultsWe identified 1484 EVARs, 122 (8%) of which were complicated by a type IA endoleak on arteriography after graft deployment, with a median follow-up of 4 years. The majority of patients underwent additional ballooning of the proximal site (52 [43%]) or placement of an aortic cuff (47 [39%]); 30 patients (25%) received a Palmaz stent, and four patients were treated with coils or anchors. At case end, only 43 (35%) of the type IA endoleaks remained; at 1 month, only 16 endoleaks persisted (13%), and only six persisted at 1 year (6%). In multivariable analysis, the only independent predictor of persistence of type IA endoleak at the conclusion of the case was the presence of extensive neck calcifications (odds ratio [OR], 9.9; 95% confidence interval [CI], 1.4-67.9; P = .02). Thirteen patients (11%) underwent reintervention for type IA endoleaks, with a time frame ranging from 3 days postoperatively to 11 years. There were three patients (2.4%) who experienced aneurysm rupture. Postoperative type IA endoleak was associated with lower survival at 1 year (79% vs 91%; relative risk, 2.5; 95% CI, 1.1-5.4; P = .02), but it did not affect long-term survival (log-rank, P = .45). Both an increase in aneurysm sac size and failure of the endoleak to resolve by case end were independent predictors of a need for reintervention (growth: OR, 8.3; 95% CI, 2.2-31.6; P < .01; persistent endoleak: OR, 7.6; 95% CI, 1.8-31.5; P < .01). A persistent type IA endoleak was not independently associated with an increase in sac size on surveillance imaging (P = .28). ConclusionsAneurysm rupture secondary to persistent type IA endoleak is rare, and most will resolve within 1 year. Extensive neck calcification is the only independent predictor of persistent type IA endoleak, and an increase in sac size warrants reintervention. These data suggest that select early persistent type IA endoleaks can be safely observed.

Characterization and outcomes of reinterventions in Food and Drug Administration-approved versus trial endovascular aneurysm repair devices

ObjectivePublished rates of reintervention after endovascular aneurysm repair (EVAR) range from 10% to 30%. We evaluated a single university center's experience with reinterventions in the context of Food and Drug Administration (FDA)-approved and trial devices. MethodsRetrospective data collection was performed for patients who underwent infrarenal EVAR and required reintervention from 2000 to 2016. Trial devices included those used in FDA feasibility and pivotal trials. Time-to-event analysis was performed using Cox regression. Predictors of mortality and explantation were evaluated using logistic regression; survival analysis was performed using Kaplan-Meier methods. ResultsFrom 2000 to 2016, there were 1835 EVARs performed, and 137 patients (116 men; mean age, 72.2 ± 10.0 years) underwent reintervention with a mean aneurysm size of 5.9 ± 1.2 cm. The median follow-up was 5 years with an overall survival of 70.1%. The overall reintervention rate was 7.5%. FDA-approved devices had a reintervention rate of 6.4%, whereas trial devices had a rate of 14.4% (P < .001). For all devices, the most common cause of reintervention was type II endoleak (52.5%), followed by type I endoleak (18.2%), type III endoleak (9.5%), limb kink (7.3%), iliac occlusive disease (5.8%), endotension (1.5%), and other. The overall mean time to first reintervention was 2.3 ± 2.5 years, and univariate Cox regression identified male gender (hazard ratio, 1.91; 95% confidence interval [CI], 1.17-3.10; P = .010) and age at the time of EVAR (hazard ratio, 1.03; 95% CI, 1.01-1.05; P = .006) as risk factors for time to first reintervention. Among patients requiring reintervention, the mean number of reinterventions for trial devices was significantly greater than that for FDA-approved devices (2.18 vs 1.65; P = .01). Trial devices requiring reintervention had a nearly threefold higher odds for the need for more than two reinterventions (odds ratio, 2.88; 95% CI, 1.12-7.37; P = .034). Trial device, cause of reintervention, and type of reintervention were not predictive of the need for explantation or mortality, but the number of reinterventions was significantly associated with the need for explantation (odds ratio, 1.86; 95% CI, 1.17-2.96; P = .012). EVAR device and the need for explantation did not have an impact on mortality. ConclusionsDespite the rigorous nature of patient enrollment in clinical trials and the development of newer iterations of investigational devices, patients undergoing EVAR with trial devices are more likely to undergo a greater number of reinterventions than with FDA-approved devices. Although mortality and the need for explantation were not significantly associated with trial devices, the finding of a greater number of reinterventions highlights the need to properly inform patients willing to partake in investigational device trials.

Management of Endograft Infection After EVAR and TEVAR - a Case Series and Literature Review

Introduction Endograft infection after EVAR (Endovascular aortic repair) or TEVAR (Thoracic endovascular aortic repair) is a rare but severe complication with high mortality. As the number of patients with endovascular aneurysm repair has increased over the last decade, the number of patients with endograft infection might also have increased. However, no guideline defines the treatment of endograft infection. Diagnosis is difficult and depends on clinical symptoms, radiological imaging and blood cultures. Surgery with graft excision, debridement and revascularisation should be proposed. Several techniques and graft materials are used. Additionally long term antibiotic therapy under close control of inflammation markers is always required. Methods We conducted a retrospective analysis of all patients treated for infected aortic endografts in our hospital between January 2008 and May 2017. Study endpoints were freedom from reinfection, survival and primary patency. An extensive electronic health database search was performed to identify articles reporting endograft infection after EVAR and TEVAR. Results We detected aortic endograft infection in three patients (100% male, median age 77 years). In all cases, infrarenal endovascular aortic aneurysm repair had been performed. The infected stent grafts were removed and anatomical revascularisation performed. One homograft and two xenografts were used as graft material. No patient was treated conservatively. A causative organism was found in 2 of the 3 cases. The patients received antibiotics for 12 weeks. Thirty day mortality was 0%. During follow-up, one patient died from bowel perforation after 2 months and another from lung cancer after 92 months. There were no reinfections. Primary patency of the reconstructions was 100%. Publications report high mortality after conservative therapy of endograft infection. There is evidence for lower mortality in patients who underwent surgery. Conclusions Removal of the infected graft, anatomical revascularisation and antibiotic therapy are important for long term survival after aortic endograft infection. Conservative therapy is only warranted in patients unsuitable for surgical treatment.

The use of thoracic stent grafts for endovascular repair of abdominal aortic aneurysms.

Objectives Stent grafts for endovascular repair of infrarenal aneurysms are commercially available for aortic necks up to 32 mm in diameter. The aim of this study was to evaluate the feasibility of endovascular repair with large thoracic stent grafts in the infrarenal position to obtain adequate proximal seal in wider necks. Methods All patients who underwent endovascular aneurysm repair using thoracic stent grafts with diameters greater than 36 mm between 2012 and 2016 were included. Follow-up consisted of CT angiography after six weeks and annual duplex thereafter. Results Eleven patients with wide infrarenal aortic necks received endovascular repair with thoracic stent grafts. The median diameter of the aneurysms was 60 mm (range 52-78 mm) and the median aortic neck diameter was 37 mm (range 28-43 mm). Thoracic stent grafts were oversized by a median of 14% (range 2-43%). On completion angiography, one type I and two type II endoleaks were observed but did not require reintervention. One patient experienced graft migration with aneurysm sac expansion and needed conversion to open repair. Median follow-up time was 14 months (range 2-53 months), during which three patients died, including one aneurysm-related death. Conclusions Endovascular repair using thoracic stent grafts for patients with wide aortic necks is feasible. In these patients, the technique may be a reasonable alternative to complex endovascular repair with fenestrated, branched, or chimney grafts. However, more experience and longer follow-up are required to determine its position within the endovascular armamentarium.

Complex EVAR Is Associated With Higher Perioperative Mortality but Not Late-Mortality Compared to Infrarenal EVAR Amongst Octogenarians

An increasing number of elderly patients are being offered endovascular repair of juxtarenal aneurysms. We sought to evaluate outcomes after complex endovascular aneurysm repair (EVAR) compared to infrarenal EVAR in a cohort of octogenarians. A single-center retrospective review was conducted with a database of consecutive patients treated with elective EVAR for abdominal aortic aneurysms (AAAs) between 2009 and 2015. Only patients aged ≥80 years were included. The complex EVAR group was treated with snorkel (Sn-EVAR) or fenestrated (F-EVAR) techniques, whereas infrarenal EVAR consisted of aneurysm repair without renovisceral involvement. Relevant demographic, anatomic/device variables, and clinical outcomes were collected. A total of 105 patients (69 infrarenal, 36 complex) were treated within the study period with a mean follow-up of 22 months. A total of 79 branch grafts were placed (61 renal, 11 celiac, 7 superior mesenteric artery) in the complex group, with a target vessel patency of 98.2% at latest follow-up. Patients with complex EVAR were more likely to be male (83.3% vs 61.1%; P = .019) and have a higher prevalence of renal insufficiency (72.2% vs 44.5%; P = .008). Thirty-day mortality was significantly more common in patients treated with complex EVAR (11.1% vs 0%; P = .012). There were no significant differences in major adverse events (P = .795) or late reintervention (P = .232) between groups. Interestingly, sac growth >10 mm was noted to be more frequent with infrarenal EVAR (17.6% vs 2.9%; P = .039). However, both type Ia (5.7% infrarenal; 5.0% complex) and type II endoleaks (32.3% infrarenal; 25.7% complex) were found to be equally common in both groups. Complex EVAR was not associated with increased all-cause mortality at the latest follow-up (P = .256; Fig). Multivariate Cox modeling demonstrated that AAAs >75 mm in diameter (hazard ratio, 5.1; 95% confidence interval, 1.8-13.9), and renal insufficiency (hazard ratio, 4.45; 95% confidence interval, 1.27-15.6) were the only independent risk factors of late death. Complex EVAR is associated with higher perioperative mortality compared to infrarenal EVAR amongst octogenarians. However, late outcomes are not significantly different. Larger aneurysms and chronic kidney disease portends greater risk of late death after EVAR, regardless of AAA complexity. These patient-related factors should be considered when offering endovascular therapy to older patients.

A preoperative risk score for transfusion in infrarenal endovascular aneurysm repair to avoid type and cross

ObjectivePreoperative type and cross are often routinely ordered before elective endovascular aneurysm repair (EVAR), but the cost of this practice is high, and transfusion is rare. We therefore aimed to stratify patients by their risk of transfusion to identify a cohort in whom a type and screen would be sufficient. MethodsWe queried the targeted vascular module of the National Surgical Quality Improvement Program (NSQIP) for all elective EVARs from 2011 to 2015. We included only infrarenal aneurysms and excluded ruptured aneurysms and patients transfused within 72 hours preoperatively. Two-thirds of the cases were randomly assigned to a model derivation cohort and one third to a validation cohort. We created and subsequently validated a risk model for transfusion within the first 24 hours of surgery (including intraoperatively), using logistic regression. ResultsBetween 2011 and 2015, there were 4875 patients who underwent elective infrarenal EVAR, only 221 (4.5%) of whom received a transfusion within 24 hours of surgery. The frequency of transfusion during the study period declined monotonously from 6.5% in 2011 to 3.2% in 2015. The factors independently associated with transfusion were preoperative hematocrit <36% (odds ratio [OR], 3.4 [95% confidence interval, 2.1-5.4]; P < .001), aortic diameter (per centimeter increase: OR, 1.2 [1.03-1.4]; P = .02), preoperative dependent functional status (OR, 2.5 [1.1-5.5]; P = .03), and chronic obstructive pulmonary disease (OR, 1.7 [1.04-2.9]; P = .04). A risk prediction model based on these criteria produced a C statistic of 0.69 in the prediction cohort and 0.76 in the validation cohort and a Hosmer-Lemeshow goodness of fit of 0.62 and 0.14, respectively. A score of <3 of 9, corresponding to a <5% probability of transfusion, would avoid preoperative type and cross in 86% of patients. Of the 4203 patients (86%) with a hematocrit >36%, only 6 (0.1%) had a risk score of >3. ConclusionsPerioperative transfusion for EVAR is becoming increasingly uncommon and is predicted well by a transfusion risk score or simply a hematocrit of <36%. Application of this risk score would avoid unnecessary type and cross in the majority of patients, leading to significant savings in both time and cost.

IP027. A Preoperative Risk Score for Transfusion in Infrarenal Endovascular Aneurysm Repair to Avoid Type and Cross

Preoperative type and crossmatch is often routinely ordered before elective endovascular aneurysm repair (EVAR), but the cost of this practice is high, and transfusion is rare. We therefore aimed to stratify patients by their risk of transfusion to identify a cohort in whom a type and screen would be sufficient. We queried the targeted vascular module of the National Surgical Quality Improvement Program database for all elective EVARs from 2011 to 2015. We included only infrarenal aneurysms and excluded ruptured aneurysms and patients who received a transfusion within 72 hours preoperatively. Two-thirds of the cases were randomly assigned to a prediction cohort and one-third to a validation cohort. We created and subsequently validated a risk model for transfusion within the first 24 hours of surgery (including intraoperatively), using logistic regression. Between 2011 and 2015, 4875 patients underwent elective infrarenal EVAR, of which only 221 (4.5%) received a transfusion within 24 hours of surgery. The frequency of transfusion over the study period declined monotonously from 6.5% in 2011 to 3.2% in 2015. The factors independently associated with transfusion were preoperative hematocrit <36% (odds ratio [OR], 3.4; 95% confidence interval [CI], 2.1-5.4; P < .001), aortic diameter (per cm increase: OR, 1.2; 95% CI, 1.03-1.4; P = .02), preoperative dependent functional status (OR, 2.5; 95% CI, 1.1-5.5; P = .03), and chronic obstructive pulmonary disease (OR, 1.7; 95% CI, 1.04-2.9; P = .04). A risk-prediction model based on these criteria (Table) produced a C statistic of 0.69 in the prediction cohort and 0.76 in the validation cohort and a Hosmer-Lemeshow goodness of fit of 0.62 and 0.14, respectively. A score of <3 of 9, corresponding to a <5% probability of transfusion, would avoid preoperative type and crossmatch in 86% of patients. Of the 4203 patients (86%) with a hematocrit >36, only six (0.1%) had a risk score >3. Perioperative transfusion for EVAR is becoming increasingly uncommon and is predicted well by a transfusion risk score, or simply a hematocrit of <36. Application of this risk score would avoid unnecessary type and crossmatch in the majority of patients, leading to significant savings in both time and cost.TablePreoperative risk scoreCriteriaPointsTotal pointsRisk of transfusion (%)Cumulative frequency (%)Hematocrit01.9741.54 <30513.0278.91 30-36324.6286.15 ≥36036.9991.02410.4596.12Diameter515.3497.99 >5.51621.9699.36 ≤5.50730.4099.75840.4199.88COPD951.29100 Yes1 No0Dependent functional status Yes2 No0COPD, Chronic obstructive pulmonary disease. Open table in a new tab

Variation in hospital costs and reimbursement for endovascular aneurysm repair: A Vascular Quality Initiative pilot project

ObjectiveComparing costs between centers is difficult because of the heterogeneity of vascular procedures contained in broad diagnosis-related group (DRG) billing categories. The purpose of this pilot project was to develop a mechanism to merge Vascular Quality Initiative (VQI) clinical data with hospital billing data to allow more accurate cost and reimbursement comparison for endovascular aneurysm repair (EVAR) procedures across centers. MethodsEighteen VQI centers volunteered to submit UB04 billing data for 782 primary, elective infrarenal EVAR procedures performed by 108 surgeons in 2014. Procedures were categorized as standard or complex (with femoral-femoral bypass or additional arterial treatment) and without or with complications (arterial injury or embolectomy; bowel or leg ischemia; wound infection; reoperation; or cardiac, pulmonary, or renal complications), yielding four clinical groups for comparison. MedAssets, Inc, using cost to charge ratios, calculated total hospital costs and cost categories. Cost variation analyzed across centers was compared with DRG 237 (with major complication or comorbidity) and 238 (without major complication or comorbidity) coding. A multivariable model to predict DRG 237 coding was developed using VQI clinical data. ResultsOf the 782 EVAR procedures, 56% were standard and 15% had complications, with wide variation between centers. Mean total costs ranged from $31,100 for standard EVAR without complications to $47,400 for complex EVAR with complications and varied twofold to threefold among centers. Implant costs for standard EVAR without complications varied from $8100 to $28,200 across centers. Average Medicare reimbursement was less than total cost except for standard EVAR without complications. Only 9% of all procedures with complications in the VQI were reported in the higher reimbursed DRG 237 category (center range, 0%-21%). There was significant variation in hospitals' coding of DRG 237 compared with their expected rates. VQI clinical data accurately predict current DRG coding (C statistic, 0.87). ConclusionsVQI data allow a more precise EVAR cost comparison by identifying comparable clinical groups compared with DRG-based calculations. Total costs exceeded Medicare reimbursement, especially for patients with complications, although this varied by center. Implant costs also varied more than expected between centers for comparable cases. Incorporation of VQI data elements documenting EVAR case complexity into billing data may allow centers to better align respective DRG reimbursement to total costs.

Ten-year single-centre experience with type II endoleaks: Intervention versus observation

Our objective was to determine the relative merits of intervention or observation of type II endoleaks (T2Ls). A retrospective analysis was performed on 386 infra-renal endovascular aneurysm repair (IR-EVAR) patients from 2006 to 2015. Annual surveillance imaging of patients undergoing EVAR at our centre were analysed, and all endoleaks were subjected to a multidisciplinary team meeting for consideration and treatment. In the 10-year time frame, 386 patients (79.5±8.7 years) underwent an IR-EVAR. Eighty-one patients (21.0%) developed a T2L and intervention was undertaken in 28 (34.6%): 17 (60.7%) were treated via a transarterial approach (TA) and 11 (39.3%) using the translumbar approach (TL). Fifty-three patients (65.4%) with T2Ls were managed conservatively. Patients who received T2L treatment had a greater proportion of recurrent T2Ls than patients who were conservatively managed ( p=0.032). T2Ls associated with aneurysmal growth were more resistant to treatment than those where there was no change or a decrease in aneurysm size during follow-up (0.033). There was no significant difference in the TA and TL approach with respect to endoleak repair success ( p=0.525). Treatment of a T2L did not confer a survival advantage compared to conservative management ( p=0.449) nor did the choice of either the TA or TL approach ( p=0.148). Our study suggests the development of a T2L associated with aneurysm growth may represent an aggressive phenotype that is resistant to treatment. However, this did not lead to an increased risk of mortality over follow-up. Neither a transarterial nor a translumbar approach to treating a T2L conferred superiority.

Perioperative outcome of endovascular repair for complex abdominal aortic aneurysms

BackgroundAs endovascular aneurysm repair (EVAR) continues to advance, eligibility of patients with anatomically complex abdominal aortic aneurysms (AAAs) for EVAR is increasing. However, whether complex EVAR is associated with favorable outcome over conventional open repair and how outcomes compare with infrarenal EVAR remains unclear. This study examined perioperative outcomes of patients undergoing complex EVAR, focusing on differences with complex open repair and standard infrarenal EVAR. MethodsWe identified all patients undergoing nonruptured complex EVAR, complex open repair, and infrarenal EVAR in the American College of Surgeons National Surgical Quality Improvement Program Targeted Vascular Module. Aneurysms were considered complex if the proximal extent was juxtarenal or suprarenal or when the Zenith Fenestrated endograft (Cook Medical, Bloomington, Ind) was used. Independent risks were established using multivariable logistic regression analysis. ResultsIncluded were 4584 patients, with 411 (9.0%) undergoing complex EVAR, 395 (8.6%) undergoing complex open repair, and 3778 (82.4%) undergoing infrarenal EVAR. Perioperative mortality was 3.4% after complex EVAR, 6.6% after open repair (P = .038), and 1.5% after infrarenal EVAR (P = .005). Postoperative acute kidney injuries occurred in 2.3% of complex EVAR patients, in 9.5% of those undergoing complex open repair (P < .001), and in 0.9% of infrarenal EVAR patients (P = .007). Compared with complex EVAR, complex open repair was an independent predictor of 30-day mortality (odds ratio [OR], 2.2; 95% confidence interval [CI], 1.1-4.4), renal function deterioration (OR, 4.8; 95% CI, 2.2-10.5), and any complication (OR, 3.7; 95% CI, 2.5-5.5). When complex vs infrarenal EVAR were compared, infrarenal EVAR was associated with favorable 30-day mortality (OR, 0.5; 95% CI, 0.2-0.9), and renal outcome (OR, 0.4; 95% CI, 0.2-0.9). ConclusionsIn this study assessing the perioperative outcomes of patients undergoing repair for anatomically complex AAAs, complex EVAR had fewer complications than complex open repair but carried a higher risk of adverse outcomes than infrarenal EVAR. Further research is warranted to determine whether the benefits of EVAR compared with open repair for complex AAA treatment are maintained during long-term follow-up.