A Canadian multicenter experience describing outcomes after endovascular abdominal aortic aneurysm repair stent graft explantation

Endotension following endovascular aortic repair: systematic review and meta-analysis on occurrence rate, treatment approaches and outcomes

INTRODUCTION

Endotension is still a poorly understood phenomenon in terms of occurrence rate, treatment indications and outcomes. The aim of this study was to report incidence, different treatment approaches and outcomes of patients affected by endotension after EVAR.

EVIDENCE AQUISITION

A systematic review of the literature (database searched: PubMed, Web of Science, Scopus, Cochrane Library) was undertaken until June 2024. Articles reporting data about occurrence rate, strategy of treatment and outcomes of patients affected by endotension, including at least five cases of endotension were included. Meta-analyses of proportions were performed using a random-effects model.

EVIDENCE SYNTHESIS

Thirteen non-randomized studies published between 2005 and 2024 were examined, with a total of 22,118 patients undergoing EVAR due to abdominal aortic aneurysm. Among them, 209 patients developed endotension during follow-up, resulting in an estimated occurrence rate of 1.6% (95% CI 0.9-2.3). Four approaches to treat endotension were reported in literature. Estimated rates were: open surgical conversion (OSC) in 37.3% (95% CI 10.5-64.0), conservative approach in 25.9% (95% CI -4.4-56.2), endovascular relining in 23.3% (95% CI 11.4-35.2) and semi-conversions in 19.5% (95% CI 4.9-34.2). The technical success (TS) in OSC, relining and semi-conversion subgroups were respectively: 93.4% (95% CI 85.7-101), 80.7% (95% CI 60.5-101) and 94.5% (95% CI 85.2-103.8).

CONCLUSIONS

OSC is the most used method, achieving high TS rate. OSC and semi-conversion presented a high CS during follow-up, while relining had lower "durability" compared to surgical treatments. Data about conservative treatment are scarce but in can be considered for selected cases.

A New Bailout Maneuver to Manage Type IIIa Endoleak Due to Displaced Renal Bridging Stent Graft in Narrow Aorta

PURPOSE

To present endovascular management of an intraoperative type IIIc endoleak (EL) in a patient with migration of the right renal artery (RRA) bridging stent graft (BSG) during branched aortic aneurysm repair.

TECHNIQUE

The technique is demonstrated in an 80-year-old woman who underwent branched endograft repair of a symptomatic 6-cm type II TAAA. The t-Branch thoracoabdominal stent graft was positioned without difficulty. A "partial graft deployment" was performed, with the distal portion of the device remaining inside the delivery system and the right renal and superior mesenteric arteries were stented. When the constraining wires were removed, the RRA BSG migration from the branch was displayed, due to endograft twisting resulting in a horizontal rotation of the t-Branch. The RRA BSG remained oriented upward with the proximal edge positioned above the distal edge of the directional branch, making cannulation very difficult. This bailout technique uses a balloon placed at the level of the RRA BSG through the celiac artery (CA) directional branch; keeping the balloon inflated and in thrust, the edge of the BSG has moved downward making it possible to engage it and relining through the RRA directional branch.

CONCLUSIONS

This paper describes an endovascular bailout technique for relining a displaced bridging stent graft, oriented upwards with the proximal edge positioned above the distal edge of the directional branch.

CLINICAL IMPACT

This sophisticated technique adds to the spectrum of bailout techniques that can be applied in cases of type IIIa EL with migration and complete separation of BSG.

Exploring Type IIIb Endoleaks: A Literature Review to Identify Possible Physical Mechanisms and Implications

Endoleaks are common complications following endovascular aneurysm repair (EVAR). They can be classified into low-pressure and high-pressure endoleaks. High-pressure endoleaks, which include Type I and Type III endoleaks, pose a significant risk of rupture and require urgent treatment. The aim of our study is to review published case reports and case series to assess the impact of Type IIIb endoleaks in EVAR and to identify possible mechanisms contributing to these endoleaks. This review targeted case reports and case series published between January 1998 and December 2022. A total of 62 case reports and case series were identified, encompassing 156 patients with Type IIIb endoleaks. Data collection was performed by three consultants who thoroughly discussed each report before registering it into an analyzable data set. Our analysis revealed that, beyond material imperfections, certain endograft configurations or conformations, endograft redundancy, and the physical forces acting on the grafts may lead to increased stress on specific parts of the endografts, potentially exceeding their design limits. Factors contributing to redundancy and unfavorable conformation of the endograft include secondary interventions for any cause (such as other types of endoleaks), EVAR performed outside the instructions for use (IFUs), endograft migrations, or larger initial aneurysm diameter.

Nationwide analysis of EVAR explantation outcomes in Korea: A comprehensive dataset study

OBJECTIVE

Endovascular aortic aneurysm repair (EVAR) is the primary treatment for abdominal aortic aneurysms, constituting 70%-80% of interventions. Despite initial benefits, long-term studies show increased mortality. Using nationwide data, this study assesses outcomes of EVAR, open aortic repair (OAR), and EVAR explantation (EE) in Korea, while exploring characteristics of late open conversion, including the rising EE incidence.

METHODS

Employing the National Health Insurance Service database, covering health-related data for nearly 50 million Koreans, the study spanned from 2002 to 2020. Patients with AAA diagnoses (I71.3 or I71.4) were categorized into OAR, EVAR, and EE groups based on procedural codes. Statistical analyses, including t-tests, Fisher's exact tests, Cox proportional hazard models, and multivariate Cox regression, assessed baseline characteristics, mortality risks, and factors within the EE group.

RESULTS

The analysis encompassed 26,195 patients, with 66.19% in the EVAR group, 31.87% in the OAR group, and 1.94% in the EE group. EVAR cases steadily increased from 2002 to 2018. Survival rates favored EVAR, followed by OAR and EE. 30-day survival was lower in EE than EVAR. Multivariate analysis for EE revealed no risk factors for 30-days survival but identified age, chronic kidney disease, high Charlson Comorbidity Index scores, and less than 6 months since EVAR as risk factors for overall mortality.

CONCLUSION

Rising EE trends with increased EVAR adoption, particularly evident in the Korean dataset, underscore inferior outcomes. This highlights the critical need for strategic initial treatment decisions and timely interventions to enhance overall results and mitigate the unfavorable EE incidence.

Systematic review and meta-analysis of outcomes after semi-conversion with graft preservation for failed endovascular aneurysm repair

OBJECTIVE

The aim of this study was to evaluate the outcomes after semi-conversion (open conversion with graft preservation) after failed endovascular aneurysm repair (EVAR). The primary outcomes were 30-day mortality and semi-conversion failure. Secondary outcomes were 30-day major systemic complications, endoleak recurrence, reinterventions, and overall survival.

METHODS

The review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The protocol was prospectively registered on PROSPERO (CRD42023421153). All studies reporting the outcomes of semi-conversions for failed EVAR were eligible for inclusion. Quality assessment was performed using the Methodological Index for Non-Randomized Studies (MINORS) tool. A random effects meta-regression of proportions was conducted using the double arcsine-Tukey transformation, given the frequent zero event rate in the primary outcome. Heterogeneity was assessed with the I2 statistic.

RESULTS

Eight studies were included in the review after full text screening. A total of 196 patients underwent semi-conversion at a mean time from EVAR of 47.4 months, 68.9% in an elective setting. Mean age at conversion was 78.1 years, and the main indication was isolated endoleak type II (70.1% of cases). Aortic clamping was not necessary in 92.3% of semi-conversions; the aortic sac was opened in 96.1% of cases; in 93.3% of cases, ligation/suture of one or more culprit arteries were performed; and aortic neck banding was executed in 29.2%. At 30 days from surgery, the pooled mortality and the major systemic complications rates were 5.3% (I2 = 24.9%) and 13.4% (I2 = 54.3%), respectively. At follow-up, endoleak recurred after 12.6% semi-conversions (I2 = 83.2%), and the rate of reinterventions was 7% (I2 = 50.1%); the semi-conversion failure rate was 5.5% (I2 = 54.1%), and the overall survival was 84.6% (I2 = 33.3%).

CONCLUSIONS

Semi-conversions have acceptable 30-day mortality rates, but the early and mid-term risks of complications, reinterventions, ruptures, and infections are not negligible. This procedure might be an alternative to complete or partial graft explant in patients whom aortic cross-clamping is not ideal.

Editor's Choice -- Type IIIb Endoleaks: Fabric Perforations of Explanted New Generation Endoprostheses

OBJECTIVE

To analyse explanted endografts (EGs) and describe fabric degradation responsible for type IIIb endoleaks.

METHODS

As part of the European collaborative retrieval programme, 32 EGs with fabric defects on macroscopic evaluation were selected. The explanted EGs were processed and studied based on the ISO 9001 certified standard protocol. It includes instructions on the collection, transportation, cleaning, and examination of explanted material. The precise analysis was performed with a digital microscope of 20 - 200 times magnification. Possible perforation mechanisms were assessed in stress tests.

RESULTS

The median time to explantation of the 32 EGs was 54 months. The explants included 65 separate EG modules, with 46 (70.8%) having a combined 388 fabric perforations. Each EG had a median of 4.79 mm2 (interquartile range [IQR] 9.86 mm2) of cumulated hole area (an average of 0.13% of an EG's area). There were 239 (61.6%) expanded polytetrafluoroethylene (ePTFE; 11 EGs) and 149 (38.4%) polyethylene terephthalate (PET; 21 EGs) fabric ruptures, with no difference in hole distribution between these types of material. Overall, 126 (32.5%) stent related and 262 (67.5%) non-stent related fabric perforations were identified. Perforations caused by fabric fatigue in ePTFE (151, 63.2%) and material kinking in PET (41, 27.5%) were the most common. The stent related perforations were larger in size (0.80 mm2) than non-stent related perforations (0.19 mm2); p < .001. Wider interstent spaces and prolonged implantation duration were associated with an increased risk of stent related perforation development; p < .001 and p = .004, respectively. Large stent related perforations were also detected in the short term, suggesting mechanical issues as underlying causes.

CONCLUSION

The fabric of EGs may degrade and lead to the development of perforations. The largest perforations are stent related. Their occurrence and size depend on the implantation time and the EG shape affected by arterial tortuosity. The conclusions are limited to the samples from a select explant group.

Systematic Review and Meta-Analysis of Elective Open Conversion versus Fenestrated and Branched Endovascular Repair for Previous Non-Infected Failed Endovascular Aneurysm Repair

OBJECTIVE

To evaluate outcomes of patients electively undergoing fenestrated and branched endovascular repair (F/B-EVAR) or open conversion for failed previous non-infected endovascular aneurysm repair (EVAR).

DATA SOURCES

Embase, MEDLINE, Cochrane Library.

REVIEW METHOD

The protocol was prospectively registered on PROSPERO (CRD42023404091). The review followed the PRISMA guidelines; certainty was assessed through the GRADE and quality through MINORS tools. Outcomes data were pooled separately for F/B-EVAR and open conversion. A random effects meta-analysis of proportions was conducted; heterogeneity was assessed with the I2 statistic.

RESULTS

Thirty eight studies were included, for a total of 1 645 patients of whom 1 001 (60.9%) underwent an open conversion and 644 (39.1%) a F/B-EVAR. The quality of evidence was generally limited. GRADE certainty was judged low for 30 day death (in both groups) and F/B-EVAR technical success, and very low for the other outcomes. Pooled 30 day death was 2.3% (I2 33%) in the open conversion group and 2.4% (I2 0%) in the F/B-EVAR conversion group (p = .36). Technical success for F/B-EVAR was 94.1% (I2 23%). The pooled 30 day major systemic complications rate was higher in the open conversion (21.3%; I2 74%) than in the F/B-EVAR (15.7%; I2 78%) group (p = .52). At 18 months follow up, the pooled re-intervention rate was 4.5% (I2 58%) in the open conversion and 26% (I2 0%) in the F/B-EVAR group (p < .001), and overall survival was 92.5% (I2 59%) and 81.6% (I2 68%), respectively (p = .005).

CONCLUSION

In the elective setting, and excluding infections, the early results of both open conversion and F/B-EVAR after failed EVAR appear satisfactory. Although open conversion presented with higher complication rates in the first 30 days after surgery, at follow up it seemed to be associated with fewer re-interventions and better survival compared with F/B-EVAR.

Realignment of Migrated Celiac Stent Graft After Branched Stent Graft Implantation Through Retrograde Cannulation of the Superior Mesenteric Artery Using a Single Vascular Access

PURPOSE

The purpose of the study was to present an endovascular management of a type IIIc endoleak (EL) in a patient with migration of the bridging stent graft of the celiac trunk (CT) after branched aortic aneurysm repair with retrograde cannulation of the superior mesenteric artery (SMA).

TECHNIQUE

The therapy was applied in a 62-year-old man who underwent a branched EVAR 2 years ago. Meanwhile, the patient was treated due to type Ia EL 6 months ago. The patient suffered in the last days from unclear hemorrhage clinically correlated with weakness. In the computed tomography angiography (CTA), an EL IIIc with a migration of the bridging stent graft from the CT branch was displayed. As vascular access, the left axillar artery was used. Due to the misaligned bridging stent graft, an antegrade cannulation was impossible, so cannulation was performed retrograde through the SMA using pancreaticoduodenal and gastroduodenal arteries. Thereafter, the EL could be repaired with bridging stent grafts. The postinterventional control showed a satisfying reconstruction without EL or embolization.

CONCLUSION

Most of the complications such as type IIIc EL after complex endovascular repair can also be treated endovascularly. This sophisticated treatment requires that necessary materials and experience are available.

Clinical presentation, operative management, and long-term outcomes of rupture after previous abdominal aortic aneurysm repair

OBJECTIVE

The aim of the present study was to evaluate the presentation trends, intervention, and survival of patients who had been treated for late abdominal aortic aneurysm rupture (LAR) after open repair (OR) or endovascular aortic aneurysm repair (EVAR).

METHODS

We reviewed the clinical data from a single-center, retrospective database for patients treated for LAR from 2000 to 2020. The end points were the 30-day mortality, major postoperative complication, and survival. The outcomes between LAR managed with EVAR (group I) vs OR were compared (group II).

RESULTS

Of 390 patients with infrarenal aortic rupture, 40 (10%) had experienced aortic rupture after prior aortic repair and comprised the LAR cohort (34 men; age 78 ± 8 years). LAR had occurred before EVAR in 30 and before OR in 10 patients. LAR was more common in the second half of the study with 32 patients after 2010. LAR after prior OR was secondary to ruptured para-anastomotic pseudoaneurysms. After initial EVAR, LAR had occurred despite reintervention in 17 patients (42%). The time to LAR was shorter after prior EVAR than after OR (6 ± 4 vs 12 ± 4 years, respectively; P = .003). Treatment for LAR was EVAR for 25 patients (63%; group I) and OR for 15 (37%, group II). LAR after initial OR was managed with endovascular salvage for 8 of 10 patients. Endovascular management was more frequent in the latter half of the study period. In group I, fenestrated repair had been used for seven patients (28%). Salvage for the remaining cases was feasible with EVAR, aortic cuffs, or limb extensions. The incidence of free rupture, time to treatment, 30-day mortality (8% vs 13%; P = .3), complications (32% vs 60%; P = .1), and disposition were similar between the two groups. Those in group I had had less blood loss (660 vs 3000 mL; P < .001) and less need for dialysis (0% vs 33%; P < .001) than those in group II. The median follow-up was 21 months (interquartile range, 6-45 months). The overall 1-, 3-, and 5-year survival was 76%, 52%, and 41%, respectively, and was similar between groups (28 vs 22 months; P = .48). Late mortality was not related to the aorta.

CONCLUSIONS

LAR after abdominal aortic aneurysm repair has been encountered more frequently in clinical practice, likely driven by the frequency of EVAR. However, most LARs, including those after previous OR, can now be salvaged with endovascular techniques with lower morbidity and mortality.

Referral Centre Experience with Infected Abdominal Aortic Endograft Explantation

OBJECTIVE

The increasing use of endovascular aneurysm repair (EVAR) appears to be associated with the burden of vascular endograft infections. Complete stent graft explantation is recommended but leads to significant mortality. This study aimed to assess the technical challenges, complications, and mortality rate following infected endograft explantation.

METHODS

Patients who underwent abdominal aortic endograft explantation for infection at the Bordeaux University Hospital from July 2008 to December 2020 were included retrospectively in this single centre observational study. The diagnosis was established based on the MAGIC criteria. The primary endpoint was 30 day mortality. Secondary endpoints were 90 day and in hospital mortality, survival, and re-infection.

RESULTS

Thirty-four patients were included, median age 69 years (interquartile range [IQR] 65, 76), with four (12%) treated as an emergency. The median time from EVAR to explantation was 17.5 months (4.5 - 36.3). In situ reconstruction was carried out with prosthetic grafts in 24 patients (71%, including 23 antimicrobial grafts combining silver and triclosan), and biological grafts in 10 (five femoral veins, four arterial allografts, three bovine patches, one biosynthetic graft). Seventeen aorto-enteric fistulae (AEnF) were addressed with direct repair of the intestinal tract (n = 10/17; 59%) or resection and anastomosis (n = 7/17; 41%). The culture was polymicrobial in 12 patients (35%) and remained sterile in four (12%). The 30 day and in hospital mortality rates were 21% (n = 7) and 27% (n = 9). Twenty-five patients (73%) presented with early post-operative complications, requiring 16 revision procedures (47%). Over a median follow up of 16.2 months (IQR 8.3, 33.6), the mortality rate was 35% (n = 12; 11 aortic related; 32%), with two re-infections (6%), both after biological reconstruction (one for an AEnF).

CONCLUSION

Early morbidity and mortality remain high after complete infected endograft explantation, even in a high volume centre. Comparison with other treatment modalities in large multicentre cohorts might be of interest.

Surgical Treatment of Sac Enlargement Due to Type II Endoleaks Following Endovascular Aneurysm Repair

An aneurysm sac enlargement caused by type II endoleak (T2EL) following endovascular aneurysm repair (EVAR) for abdominal aortic aneurysms may cause serious complications such as rupture. Consequently, methods that preoperatively prevent or postoperatively treat T2EL have been employed. When significant aneurysm enlargement occurs due to persistent T2EL, embolization is first performed through several access points. However, although these endovascular reinterventions have a high technical success rate and are safe, their effectiveness remains questionable. When such endovascular procedures fail to stabilize sac enlargement, open surgical conversion (OSC) becomes the last-resort treatment option. We review several strategies of OSC for the repair of T2EL following EVAR. Among the three main OSC procedures, namely, complete endograft removal, partial endograft removal, and complete endograft preservation, partial endograft removal under infrarenal clamping was considered the most appropriate owing to its less invasiveness and durability.

Open conversion after failed endovascular aneurysm repair is increasing and its 30-day mortality is higher than that after primary open repair

BACKGROUND

Endovascular aneurysm repair (EVAR) has become the preferred treatment of abdominal aortic aneurysms (AAAs). Recent studies have demonstrated that cases of EVAR failure repair and subsequent open conversion have increased. The aim of the present study was to evaluate the national trend of annual cases and assess the 30-day outcomes of conversion to open repair after failed EVAR compared with primary open repair.

METHODS

The National Surgical Quality Improvement Program database was queried for relevant Current Procedural Terminology and International Classification of Diseases, Ninth and Tenth Revision, codes to identify patients who had undergone conversion to open repair or primary open repair of nonruptured AAAs from 2009 to 2018. The annual trend of cases was assessed, and the perioperative outcomes of both procedures were compared. Multivariable logistic regression analyses were conducted to identify independent perioperative factors associated with mortality.

RESULTS

Of the 9635 patients with nonruptured AAAs included in the present analysis, 9250 had undergone primary repair and 385 had required open conversion. During the 10-year period, the annual number of cases of open conversion had steadily increased and that of primary repair had decreased. The incidence of postoperative complications was similar between both groups, except for cardiac arrest, which had occurred more frequently in the open conversion group. The 30-day mortality was higher in the open conversion group than in the primary group (9.6% vs 3.9%; P < .0001). Open conversion was also independently associated with higher odds of death (adjusted odds ratio [OR], 2.1; 95% confidence interval [CI], 1.8-2.4; P < .0001). When the average mortality in both groups was compared between the first and last 5 years, no difference was found (open conversion: 9.8% vs 9.5% [P = 1.00]; primary repair: 3.6% vs 4.2% [P = .19]). Other perioperative factors independently associated with mortality included increased age (OR, 1.8; 95% CI, 1.5-2.1; P < .0001), American Society of Anesthesiologists class ≥III (OR, 2.7; 95% CI, 1.1-6.6; P = .029), insulin-dependent diabetes (OR, 2.0; 95% CI, 1.2-3.3; P = .005), chronic obstructive pulmonary disease (OR, 1.4; 95% CI, 1.1-1.8; P = .006), the presence of dyspnea at rest (OR, 3.3; 95% CI, 1.8-6.1; P < .0001), and a high preoperative hematocrit (OR, 0.94; 95% CI, 0.93-0.97; P < .0001).

CONCLUSIONS

Open conversion to treat nonruptured AAAs after failed EVAR was independently associated with higher mortality. Also, the annual cases of open conversion have continued to increase without any significant changes in postoperative mortality. This highlights the danger of open conversion and stresses the need for better solutions to prevent and manage EVAR failure.

Outcomes of EVAR Conversion in Octogenarians Treated at a High-Volume Aorta Center

INTRODUCTION

Endovascular aortic aneurysm repair(EVAR) is the dominant treatment strategy for infrarenal abdominal aortic aneurysms(AAA) but is especially preferred among octogenarian(age ≥80-years) patients due to concerns surrounding comorbidity severity and physiological frailty. Correspondingly, EVAR failure resulting in subsequent open conversion(EVAR-c) has been increasingly reported in older patients but there is a paucity of literature focusing on outcomes in this subgroup. The purpose of this analysis was to evaluate our experience with EVAR-c in octogenarians(≥80-years) compared to younger patients(age <80-years).

METHODS

A retrospective review of all non-mycotic EVAR-c procedures(2002-2020) at a single high-volume academic hospital with a dedicated aorta center(https://www.uf-health-aortic-disease-center) was performed. Patients(n=162) were categorized into octogenarian(age ≥80; n=43) and non-octogenarian(age<80; n=119) cohorts and subsequently compared. The primary end-point was 30-day mortality. Secondary end-points included complications, 90-day mortality, and overall survival. Cox regression determined effects of selected covariates on mortality risk. Kaplan-Meier methodology estimated survival.

RESULTS

No difference in pre-admission EVAR re-intervention rates was present(octogenerians-42% vs. non-octogenerians-43%;p=1) although time to first re-intervention was greater in octogenarians(41 vs. non-octogenarians, 15-months;p=.01). Concordantly, time to EVAR-c was significantly longer among octogenarian patients(61 vs. non-octogenarians, 39-months;p<.01). No difference in rupture presentation was evident(14% vs. 10%;p=.6); however, elective EVAR-c occurred less frequently(octogenerians-42% vs. non-octogenerians-59%;p=.07). AAA diameter was significantly larger for elective octogenarian EVAR-c(7.8±1.9cm vs. non-octogenarians, 7.0±1.5cm;p=.02) and type 1a endoleak was the most common indication overall(58%;n=91). Among all presentations, a trend in higher 30-day mortality was evident for octogenarian patients(16% vs. non-octogenarians, 7%;p=.06). Similarly 90-day mortality was greater among octogenarians(26% vs. non-octogenarians, 10%;p=.02). However, incidence of any complication(56% vs. 49%;p=.5), readmission(12% vs. 6%;p=.3), unplanned re-operation(10% vs. 5%;p=.5) and LOS(11 vs. 9 days;p=.3) was not significantly different. Age ≥80 was predictive of short-term mortality after non-elective but not elective cases; however, increasing comorbidity number, non-elective admission and renal/mesenteric revascularization had the strongest association with mortality risk. One- and three-year survival was not different between groups when comparing all patients after the first 90-days postoperatively.

CONCLUSION

Although higher unadjusted peri-operative mortality occurred among octogenarian patients, risk-adjusted elective outcomes were comparable to younger EVAR-c subjects when treated at a high-volume aortic surgery center. This underscores the importance of appropriate patient selection and modulation of operative complexity when feasible to achieve optimal results. Providers caring for octogenarian patients with EVAR failure should consider timely elective referral to high-volume aorta centers to reduce resource utilization and frequency of non-elective presentations.

The failing endograft-A systematic review of aortic graft explants and associated outcomes

OBJECTIVE

The prominent use of endovascular stent grafts in the management of abdominal aortic aneurysms is associated with increased descriptions of late complications such as graft infection and endoleaks, which can confer significant morbidity and mortality. Failed endovascular management of late complications often requires open conversion and graft explantation. This systematic review sought to highlight the peri- and post-operative course of patients undergoing aortic graft explants to inform readers of the associated morbidity and mortality of patients undergoing this procedure.

METHODS

The review was conducted in accordance with PRISMA guidelines. A search of the PubMed, Google Scholar and Ovid MEDLINE databases from January 1995 to April 2021 was performed with a combination of MeSH terms pertaining to endovascular aneurysm repair and open conversion. Articles were screened and included based on pre-determined selection criteria.

RESULTS

A total of 818 studies were identified, with 41 meeting inclusion criteria. These studies examined a total of 1324 patients, 84.3% of whom were male with a mean age of 74 years at explantation. Mean time to graft explantation was 36 months, with a mean aneurysm size of 66 mm. The majority of aortic explants were performed for persistent endoleaks (68%), and 10% for infection. There was high morbidity with the procedure, with high rates of post-operative complications (mean, 37%) and 30-day mortality (11%). The most common complications included renal (15%), respiratory (12%) and cardiac (9%). Most explanted grafts were first-generation endografts. Morbidity and mortality rates were reduced in patients undergoing elective explants compared to emergent procedures (3.3% compared to 43.4%).

CONCLUSION

Aortic graft explant remains a highly co-morbid procedure, with high rates of peri- and post-operative complications and mortality. The number of explant procedures reported over the past 25 years has increased, reflecting the prominent use of EVAR in the management of AAAs. Whilst remaining a highly co-morbid procedure, patients undergoing elective explants had markedly reduced rates of mortality and morbidity compared to emergent explants. Thus, clinical focus should be on identifying patients who require graft explantation early to perform these procedures in an elective setting.

Impact of proximal neck anatomy on short-term and mid-term outcomes after treatment of abdominal aortic aneurysms with new-generation low-profile endografts. Results from the multicentric "ITAlian north-east registry of ENDOvascular aortic repair with the BOltOn Treo endograft (ITA-ENDOBOOT)"

INTRODUCTION

The aim of the study was to evaluate the short-term and mid-term technical and clinical outcomes of the Bolton Treo endograft in subjects with abdominal aortic aneurysm (AAA) requiring endovascular aortic repair (EVAR) and assess if presence of hostile proximal neck would represent a risk factor for increased failure rates.

METHODS

A retrospective review of all consecutive patients who had undergone elective or non-elective EVAR with the Bolton Treo endograft at five institutions located in the North-East of Italy (January 2016-December 2020) was performed. The main exposure variable for this study was presence of hostile (HAN) or friendly (FAN) aortic neck.

RESULTS

A total of 137 consecutive patients were treated with the Bolton Treo endograft at participating institutions; of these 63 (46%) presented HAN while 74 (54%) had FAN. At baseline, no significant differences were observed in the distribution of demographics and comorbidities between study groups. Two type Ia endoleaks (EL) were detected at completion angiography, all in patients with HAN but none in patients with FAN (3% vs 0%, p=.04), but no type III EL were identified in the whole cohort. The median duration of follow-up in the study cohort was 30 months (IQR 22-34 months) and was similar between study groups (p=.87). At three-years, survival estimates were 89% and 91% (p=.82) in patients with HAN and FAN, respectively. At three years, patients with HAN had significantly lower freedom from type IA endoleak as compared with patients with FAN (87% vs 94%, p=.02). No significant differences were found between study groups in the three-year estimates of freedom from reinterventions (80% vs 86%, p=.28). Using cox proportional hazards, presence of type II EL (HR 3.15, 95%CI 1.18-8.5, p=.02) and presence of type IA EL (HR 4.22, 95%CI 1.39-12.85, p=.01) were found as independent predictors for reinterventions in univariate analysis, although they were no longer significant in the multivariate model. Freedom from sac increase >5mm at three years were not significantly different between study groups (92% vs 91%, p=.95).

CONCLUSIONS

Within a contemporary multicentric real-world experience, EVAR with the Bolton Treo endograft shows a satisfactory safety profile in the immediate postoperative phase and acceptable outcomes during mid-term follow-up. Presence of HAN is correlated with development of type Ia EL (either early following stent-graft implantation or late after EVAR) which, in turn, may represent a significant factor leading to reinterventions.

Dependent functional status rather than age is a better predictor of adverse outcomes after excision of an infected abdominal aortic graft

OBJECTIVE

The optimal management of infected abdominal aortic grafts is complete surgical excision plus in situ or extra-anatomic revascularization in patients who can tolerate this morbid operation. In addition to using age and the presence of comorbidities for risk assessment, physicians form a global clinical impression when deciding whether to offer excision or to manage conservatively. Functional status is a distinct objective measure that can inform this decision. This study examines the relative impact of age and functional status on outcomes of infected abdominal aortic graft excision to guide surgical decision-making.

METHODS

Current Procedural Terminology code 35907 was used to identify patients undergoing excision of infected abdominal aortic graft in the 2005 to 2017 American College of Surgeons - National Surgical Quality Improvement Program (NSQIP) database. Patients were stratified by the upper age quartile (75 years old) as a cutoff, and then by functional status, independent vs dependent (as defined by NSIQIP). The patients were then stratified into four groups: Younger (<75)/Independent, Younger (<75)/Dependent, Older (≥75)/Independent, and Older (≥75)/Dependent. Outcomes measured included 30-day mortality and major organ-system dysfunction.

RESULTS

There were 814 patients who underwent infected abdominal aortic graft excision: 508 patients (62%) were Younger/Independent, 89 patients (11%) were Younger/Dependent, 176 patients (22%) were Older/Independent, and 41 patients (5%) were Older/Dependent. There was no statistically significant difference in 30-day mortality for Younger/Dependent (odds ratio [OR], 1.66; 95% confidence interval [CI], 0.90-3.09; P = .536) or Older/Independent (OR, 1.31; 95% CI, 0.78-2.19; P = .311) patients when compared with Younger/Independent patients, which suggests that neither old age nor dependent functional status by itself adversely affects mortality. However, when both factors were present, Older/Dependent patients had three times higher mortality when compared with Younger/Independent patients (41.5% vs 13.4%, respectively; OR, 3.13; 95% CI, 1.46-6.71; P = .003). Furthermore, as long as patients presented with independent functional status, old age by itself did not adversely affect major organ-system dysfunction (ORs for Older/Independent vs Younger/Independent were 0.76 [P = .454], 1.04 [P = .874], and 0.90 [P = .692] for cardiac, pulmonary, and renal complications, respectively). On the contrary, even in younger patients, dependent functional status was significantly associated with higher pulmonary complications (Younger/Dependent vs Younger/Independent: OR, 2.22; 95% CI, 1.33-3.73; P = .002) and higher rates of unplanned reoperation (OR, 2.67; 95% CI, 1.62-4.41; P < .0001).

CONCLUSIONS

Dependent functional status has significant association with adverse outcomes after excision of infected abdominal aortic grafts, whereas old age alone does not. Therefore, this procedure could be considered in appropriately selected elderly patients with otherwise good functional status. However, caution should be applied in dependent patients regardless of age due to the risk of pulmonary complications.

Early and mid-term outcomes following open surgical conversion after failed endovascular aneurysm repair from the "Italian North-easT RegIstry of surgical Conversion AfTer Evar" (INTRICATE)

OBJECTIVE

To report the early and mid-term outcomes following open surgical conversion (OSC) after failed endovascular aortic repair (EVAR) using data from a multicentric registry.

METHODS

A retrospective study was carried out on consecutive patients undergoing OSC after failed EVAR at eight tertiary vascular units from the same geographic area in the North-East of Italy, from April 2005 to November 2019. Study endpoints included early and follow-up outcomes.

RESULTS

144 consecutive patients were included in the study. Endoleaks were the most common indication for OSC (50.7%), with endograft infection (24.6%) and occlusion (21.9%) being the second most prevalent causes. The overall rate of 30-day all-cause mortality was 13.9% (n=20); 32 patients (22.2%) experienced at least one major complication. Mean length of stay (LoS) was 13 ± 12.7 days. On multivariate logistic regression, age (OR 1.09, 95% CI 1.01-1-19, p= .02), renal clamping time (OR 1.07, 95% CI 1.02-1.13, p= .01), and suprarenal/celiac clamping (OR 6.66, 95% CI 1.81-27.1, p= .005) were identified as independent predictors of peri-operative major complications. Age was the only factor associated with peri-operative mortality at 30 days. Renal clamping time > 25 minutes had sensitivity of 65% and specificity of 70% in predicting the occurring of major adverse events (AUC 0.72; 95% CI 0.61-0.82). At 5 years, estimated survival was significantly lower for patients treated due to aortic rupture/dissection (28%, 95% CI 13-61), compared to patients in whom the indication for treatment was endoleak (54%, 95% CI 40-73), infection (53%, 95% CI 30-94), or thrombosis (82%, 95% CI 62-100; p= .0019). 5-year survival rates were significantly lower in patients who received emergent treatment (28%, 95% CI 14-55) as compared with those who were treated in urgent (67%, 95% CI 48-93) or elective setting (57%, 95% CI 43-76; p= .00026). Subjects who received suprarenal/celiac (54%, 95% CI 36-82) or suprarenal (46%, 95% CI 34-62) aortic cross-clamping had lower survival rates at 5 years than those whose aortic-cross clamp site was infrarenal (76%, 95% CI 59-97; p= .041). Using multivariate Cox Proportional Hazard, older age and emergency setting were independently associate with higher risk for overall 5 years mortality.

CONCLUSIONS

OSC after failed EVAR was associated with relatively high rates of early morbidity and mortality, particularly for emergency setting surgery. Endoleaks with secondary sac expansion were the main indication for OSC and suprarenal aortic cross-clamping was frequently required. Endograft infection and emergent treatment remained associated with poorer short-term and long-term survival.