Impact of Isolated Type 2 Endoleak on Subsequent Cardiovascular Events and Mortality

BACKGROUND

Assess subsequent cardiovascular events and all-cause mortality in patients with intact abdominal aortic aneurysm (AAA) treated by endovascular aneurysm repair (EVAR) according to the existence of isolated endoleak type 2 (EL2) at 1 year after EVAR implantation.

METHODS

This retrospective, single-center study included patients treated with EVAR between 2010 and 2017 in the vascular surgery department of the University Hospital of Lyon with an infrarenal AAA > 50 mm. The baseline clinical characteristics collected just before EVAR were retrieved from electronic patient records of our institution. AAA characteristics, procedure, and the 1-year postoperative computed tomography angiography (CTA) were reported. Study end points, major adverse cardiovascular events (MACE), major adverse lower-extremity events (MALE), and all-cause mortality were recorded during follow-up. Patients were divided into 2 groups according to the presence of isolated EL2 (EL2 +) or absence (EL2 -) of any endoleak on CTA at 1 year. MACE, MALE, and all-cause mortality were compared between both groups.

RESULTS

During the study period, 589 patients were treated by endovascular surgery and 207 were included. According to the CTA results at 1 year, 60 patients (29%) were included in the EL2 + group and 147 patients (71%) in the EL2 - group. A total of 109 patients (53%) experienced a MACE or MALE; significantly fewer patients in the EL2 + than in the EL2 - group did so (P = 0.009). There were 47 patients (23%) who experienced at least 1 MALE, and the frequency was significantly lower in the EL2 + group (P = 0.017).

CONCLUSIONS

Patients with AAA treated by EVAR who did not develop EL2 at 1 year were at higher risk of MALE during follow-up. This might be explained by more frequent symptomatic lower extremity peripheral arterial disease at baseline in this group. These patients therefore require a closer follow-up and strict control of cardiovascular risk factors to prevent cardiovascular morbi-mortality.

Volume Measurements for Surveillance after Endovascular Aneurysm Repair using Artificial Intelligence

OBJECTIVE

Surveillance after endovascular aneurysm repair (EVAR) is suboptimal due to limited compliance and relatively large variability in measurement methods of abdominal aortic aneurysm (AAA) sac size after treatment. Measuring volume offers a more sensitive early indicator of aneurysm sac growth or regression and stability, but is more time consuming and thus less practical than measuring maximum diameter. This study evaluated the accuracy and consistency of the artificial intelligence (AI) driven software PRAEVAorta 2 and compared it with an established semi-automated segmentation method.

METHODS

Post-EVAR aneurysm sac volumes measured by AI were compared with a semi-automated segmentation method (3mensio software) in patients with an infrarenal AAA, focusing on absolute aneurysm volume and volume evolution over time. The clinical impact of both methods was evaluated by categorising patients as showing either AAA sac regression, stabilisation, or growth comparing the 30 day and one year post-EVAR computed tomography angiography (CTA) images. Inter- and intra-method agreement were assessed using Bland-Altman analysis, the intraclass correlation coefficient (ICC), and Cohen's κ statistic.

RESULTS

Forty nine patients (98 CTA images) were analysed, after excluding 15 patients due to segmentation errors by AI owing to low quality CT scans. Aneurysm sac volume measurements showed excellent correlation (ICC = 0.94, 95% confidence interval [CI] 0.88 - 0.99) with good to excellent correlation for volume evolution over time (ICC = 0.85, 95% CI 0.75 - 0.91). Categorisation of AAA sac evolution showed fair correlation (Cohen's κ = 0.33), with 12 discrepancies (24%) between methods. The intra-method agreement for the AI software demonstrated perfect consistency (bias = -0.01 cc), indicating that it is more reliable compared with the semi-automated method.

CONCLUSION

Despite some differences in AAA sac volume measurements, the highly consistent AI driven software accurately measured AAA sac volume evolution. AAA sac evolution classification appears to be more reliable than existing methods and may therefore improve risk stratification post-EVAR, and could facilitate AI driven personalised surveillance programmes. While high quality CTA images are crucial, considering radiation exposure is important, validating the software with non-contrast CT scans might reduce the radiation burden.

The sac evolution imaging follow-up after endovascular aortic repair: An international expert opinion-based Delphi consensus study

OBJECTIVE

Management of follow-up protocols after endovascular aortic repair (EVAR) varies significantly between centers and is not standardized according to sac regression. By designing an international expert-based Delphi consensus, the study aimed to create recommendations on follow-up after EVAR according to sac evolution.

METHODS

Eight facilitators created appropriate statements regarding the study topic that were voted, using a 4-point Likert scale, by a selected panel of international experts using a three-round modified Delphi consensus process. Based on the experts' responses, only those statements reaching a grade A (full agreement ≥75%) or B (overall agreement ≥80% and full disagreement <5%) were included in the final document.

RESULTS

One-hundred and seventy-four participants were included in the final analysis, and each voted the initial 29 statements related to the definition of sac regression (Q1-Q9), EVAR follow-up (Q10-Q14), and the assessment and role of sac regression during follow-up (Q15-Q29). At the end of the process, 2 statements (6.9%) were rejected, 9 statements (31%) received a grade B consensus strength, and 18 (62.1%) reached a grade A consensus strength. Of 27 final statements, 15 (55.6%) were classified as grade I, whereas 12 (44.4%) were classified as grade II. Experts agreed that sac regression should be considered an important indicator of EVAR success and always be assessed during follow-up after EVAR.

CONCLUSIONS

Based on the elevated strength and high consistency of this international expert-based Delphi consensus, most of the statements might guide the current clinical management of follow-up after EVAR according to the sac regression. Future studies are needed to clarify debated issues.

The real-world incidence and predictors of sac regression in patients with infrarenal abdominal aortic aneurysm after standard EVAR

OBJECTIVE

Sac regression (SR) is a surrogate marker of satisfied endovascular aneurysm repair (EVAR). This research aims to investigate the incidence and predictors of SR in a Chinese population.

DESIGN

Single centre retrospective cohort study.

METHODS

Consecutive patients with infrarenal abdominal aortic aneurysms (AAAs) who underwent standard EVAR were retrospectively reviewed. SR was defined as sac shrinkage > 5 mm on computed tomography images, while major SR (MaSR) was ≥ 10 mm sac shrinkage. The cumulative rate was calculated by Kaplan-Meier analysis and predictors were identified by the Cox regression model.

RESULTS

A total of 469 patients (median age, 71 years old) were included. The majority of them (86.6 %) were male. With a median time of 13.6 months, SR was detected in 129 (27.5 %) patients after the index EVAR. Compared with never smokers, current smokers were more likely to experience SR (adjusted HR 2.630, p < .001), while former smokers did not show any significant difference. Multivariate Cox regression also showed that maximal aneurysm diameter (adjusted HR 1.012, p = 0.035) and female (adjusted HR 1.675, p = .045) were independent predictors of SR. A total of 51 (10.9 %) patients had MaSR at a median time of 15.4 months after EVAR. In multivariate analysis, maximal aneurysm diameter and Zenith stent graft were independently associated with MaSR.

CONCLUSION

In Chinese population, the incidence of SR and MaSR was 27.5 % and 10.9 % after EVAR, respectively. Maximal aneurysm diameter and female were independent predictors of SR. Compared with never smokers, it was more likely to have SR in current smokers.

Predictors of overall mortality after endovascular abdominal aortic repair - A single centre study

OBJECTIVES

A current and ongoing challenge is to reduce patient mortality after endovascular abdominal aortic repair (EVAR). This study aimed to assess the predictors of all-cause mortality after EVAR.

METHODS

Data regarding the demographic characteristics, comorbidities, laboratory values, selected anatomical factors, post-EVAR treatment, surveillance and complications of patients who underwent elective EVAR for non-ruptured abdominal aortic aneurysm (AAA) between January 2010 and January 2021 were evaluated. Mortality was assessed until 10 October 2023. Multivariate analyses were performed after adjusting for age, hypertension, diabetes mellitus, dyslipidaemia, sex, smoking, number of lumbar arteries, patency of inferior mesenteric artery (IMA), IMA diameter and reinterventions.

RESULTS

This study included 196 patients (183 men and 13 women) with a mean age of 72.4 ± 7.67 years. The overall mortality rate during a mean follow-up period of 5.75 ± 3.1 years was 50.0% (N = 98). The 2-, 5- and 10-year mortality rates were 9.7%, 32.0% and 66.6%, respectively. The mortality rates decreased by 59% in patients with reinterventions (hazard ratio [HR]: 0.41; 95% confidence interval [CI]: 0.23-0.73; p = .002) and by 59% in patients treated with angiotensin-converting enzyme (ACE) inhibitors or angiotensin II receptor blockers (ARBs) (HR: 0.41; 95% CI: 0.26-0.66; p < .001). Chronic anticoagulation was associated with 2.09-fold higher mortality (HR: 2.09; 95% CI: 1.19-3.67; p = .010), and coronary artery disease (CAD) was associated with 1.74-fold higher mortality (HR: 1.74; 95% CI: 1.09-2.78; p = .021). Pre-EVAR AAA diameter and 1-year post-EVAR sac diameter were positively associated with mortality (HR: 1.05; 95% CI: 1.03-1.08; p < .001, and HR: 1.05; 95% CI: 1.03-1.07; p < .001, respectively), that is, an increase of pre-EVAR and/or 1-year post-EVAR AAA diameter by 1 mm was associated with a 5% higher risk of all-cause mortality.

CONCLUSIONS

Reinterventions and treatment with ACE inhibitors or ARBs may be associated with decreased post-EVAR mortality. A greater pre-EVAR, a post-EVAR AAA diameter, CAD and chronic anticoagulation were associated with higher all-cause mortality post-EVAR.

Type II endoleaks after fenestrated/branched endografting for juxtarenal and pararenal aortic aneurysms

OBJECTIVE

Persistent type II endoleaks (pEL2s) are not uncommon after endovascular aneurysm repair and their impact on long-term outcomes is well-documented. However, their occurrence and natural history after fenestrated/branched endografting (F/B-EVAR) for juxtarenal and pararenal aneurysms (J/P-AAAs) have been scarcely investigated. Aim of this study was to report incidence, risk factors, and natural history of pEL2 after F/B-EVAR in J/P-AAAs.

METHODS

Between 2016 and 2022, all J/P-AAAs undergoing F/B-EVAR were prospectively collected and retrospectively analyzed. EL2 were assessed at the completion angiography, at 30 days and after 6 months as primary outcomes. Preoperative risk factors for pEL2, follow-up survival, freedom from reinterventions (FFR) and aneurysm shrinkage (≥5 mm) were considered as secondary outcomes.

RESULTS

Of 132 patients, there were 88 (67%) JAAAs and 44 (33%) PAAAs. Seventeen EL2 (13%) were detected at the completion angiography and 36 (27%) at 30-day computed tomography angiography. The mean follow-up was 28 ± 23 months. Eleven (31%) EL2 sealed spontaneously within 6 months and three new cases were detected, for an overall of 28 pEL2/107 patients (26%) with available radiological follow-up of ≥6 months. Preoperative antiplatelet therapy (odds ratio, 4.7; 95% confidence interval [CI[, 1-22.1; P = .05), aneurysm thrombus volume of ≤40% and six or more patent aneurysm afferent vessels (odds ratio, 7.2; 95% CI, 1.8-29.1; P = .005) were independent risk factors for pEL2. The estimated 3-year survival was 80%, with no difference between cases with and without pEL2 (78% vs 85%; P = .08). The estimated 3-year FFR was 86%, with no difference between cases with and without pEL2 (81% vs 87%; P = .41). Four cases (3%) of EL2-related reinterventions were performed. In 65 cases (49%), aneurysm shrinkage was detected. pEL2 was an independent risk factor for absence of aneurysm shrinkage during follow-up (hazard ratio, 3.2; 95% CI, 1.2-8.3; P = .014). Patients without shrinkage had lower follow-up survival (64% vs 86% at 3-year; P = .009) and FFR (74% vs 90% at 3 years; P = .014) than patients with shrinkage.

CONCLUSIONS

PEL2 is not infrequent (26%) after F/B-EVAR for J/P-AAAs and is correlated with preoperative antiplatelet therapy, aneurysm thrombus volume of ≤40%, and six or more patent sac afferent vessels. Patients with pEL2 have a diminished aneurysm shrinkage, which is correlated with lower follow-up survival and FFR compared with patients with aneurysm shrinkage.

The Effect of EndoAnchors on Aneurysm Sac Regression for Patients Treated With Infrarenal Endovascular Repair With Hostile Neck Anatomies: A Propensity Scored Analysis

PURPOSE

To analyze sac evolution patterns in matched patients with hostile neck anatomy (HNA) treated with standard endovascular aneurysm repair (sEVAR) and endosutured aneurysm repair (ESAR).

METHODS

Observational retrospective study using prospectively collected data between June 2010 and December 2019. ESAR group data were extracted from the primary arm of the PERU registry with an assigned identifier (NCT04100499) at 8 centers and those from the sEVAR came from 4 centers. Suitability for inclusion required: no proximal endograft adjuncts (besides EndoAnchor use), ≤15 mm neck length and minimum of 12-months follow-up imaging. Bubble-shaped neck (noncylindrical short neck with discontinuous seal) aspect was analyzed. Both groups were analyzed using propensity score matching (PSM) for aortic neck length, width, angulation, and device fixation type. Main outcome assessed was sac evolution patterns (sac expansion and regression were defined as >5mm increase or decrease, of the maximum sac diameter respectively; all AAAs within this ±5 mm range in diameter change were considered stable) and secondary outcomes were type-Ia endoleaks; other endoleaks and mortality. A power analysis calculation >80% was confirmed for sac regression evaluation.

RESULTS

After exclusions, PSM resulted in 96 ESAR and 96 sEVAR patients. Mean imaging follow-up (months) was 44.4±21.3 versus 43.0±19.6 (p=0.643), respectively. The overall number of patients achieving sac regression was higher in the ESAR group (n=57, 59.4% vs n=31, 32.3%; p<0.001) and the cumulative sac regression achieved at 5 years was 65% versus 38% (p=0.003) in favor of the ESAR group. There were no statistically significant differences in type-Ia endoleak and/or other endoleaks. Univariate analysis for sac regression patients in the sEVAR and ESAR group individually showed the bubble-shape neck as a predictor of sac regression failure. There were no statistical differences in overall and aneurysm-related mortality.

CONCLUSION

Endosutured aneurysm repair provided improved rates of sac regression for patients with AAA and HNA when compared with sEVAR at midterm and up to 5 years, despite similar rates of type-Ia endoleaks, and the need to consider some important limitations. The presence of bubble-shaped neck was a predictor of sac regression failure for both groups equally.

CLINICAL IMPACT

The use of EndoAnchors aids and improves EVAR treatment in hostile neck anatomies by an increased rate of sac regression when compared to EVAR treatment alone in up to 5 year analysis. Moreover, a trend to reduced number of type Ia endoleaks is also achieved, although not significant in the present study. This data, adds to current and growing evidence on the usefulness of EndoAnchors for AAA endovascular treatment.

Five Year Post-Endovascular Aneurysm Repair Aneurysm Sac Evolution in the GREAT Registry: an Insight in Diabetics Using Propensity Matched Controls

OBJECTIVE

To assess differences in the five year abdominal aortic aneurysm (AAA) sac regression rate after endovascular aneurysm repair (EVAR) in patients with and without diabetes mellitus (DM).

METHODS

An international prospective registry (Europe, USA, Brazil, Australia, and New Zealand) of patients treated with the GORE EXCLUDER endograft. All scheduled EVARs for infrarenal AAA between 2014 and 2016 with complete five year imaging follow up were included. Emergency procedures, ancillary proximal procedures, and inflammatory and infectious aetiologies were excluded. Descriptive and inferential statistics, and Cox proportional hazards survival models were used. A control group of patients without DM with similar age and comorbidities was selected using propensity scores, matched in a 1:2 scheme.

RESULTS

A total of 2 888 patients (86.1% male; mean age 73.5 ± 8 years) was included, of whom 545 (18.9%) had DM. Patients with DM had higher rates of hypertension (89.2% vs. 78.4%), dyslipidaemia (76.0% vs. 60.7%), coronary artery disease (52.3% vs. 37.9%), and chronic renal impairment (20.9% vs. 14.0%) (all p < .001). The mean pre-procedural AAA diameter was 58.1 ± 10 mm. Five years post-EVAR, the type 1A endoleak rate was 1.1% (0.6% DM vs. 1.2% non-DM), the endograft related re-intervention rate was 7.3% (6.2% vs. 7.6%), the major adverse cardiovascular event (MACE) rate was 1.4% (1.1% vs. 1.5%), and aortic related mortality rate was 1.0% (0.6% vs. 1.2%), without statistically significant differences between groups. The overall five year mortality rate was higher in diabetics (36.3% vs. 30.5%; hazard ratio [HR] 1.30, 95% confidence interval [CI] 1.07 - 1.58; p = .001). No statistically significant differences were found in sac regression rate (≥ 5 mm) between diabetics and non-diabetics 70.0% vs. 73.1%; HR 0.88, 95% CI 0.75-1.04; p = .131. These differences remained statistically non-significant after excluding patients performed out of instructions for use (p = .61) and patients with types 1, 2 or 3 endoleaks (p = .39).

CONCLUSION

The paradoxical relationship between DM and AAA does not appear to result in differences in post-EVAR sac regression rates. However, even when controlling for other comorbidities, patients with DM undergoing EVAR may have a higher five year mortality rate.

Aneurysm sac shrinkage at 1 year after fenestrated-branched endovascular aortic repair of complex aortic aneurysms offers mid-term survival advantage

OBJECTIVES

To investigate the impact of 1-year changes in aneurysm sac diameter on patient survival after fenestrated-branched endovascular aortic repair (FB-EVAR) of complex abdominal aortic aneurysms or thoracoabdominal aortic aneurysms.

METHODS

We reviewed the clinical data of patients enrolled in a prospective nonrandomized study investigating FB-EVAR (2013-2022). Patients with sequential follow up computed tomography scans at baseline and 6 to 18 months after FB-EVAR were included in the analysis. Aneurysm sac diameter change was defined as the difference in maximum aortic diameter from baseline measurements obtained in centerline of flow. Patients were classified as those with sac shrinkage (≥5 mm) or failure to regress (<5 mm or expansion) according to sac diameter change. The primary end point was all-cause mortality. Secondary end points were aortic-related mortality (ARM), aortic aneurysm rupture (AAR), and aorta-related secondary intervention.

RESULTS

There were 549 patients treated by FB-EVAR. Of these, 463 patients (71% male, mean age, 74 ± 8 years) with sequential computed tomography imaging were investigated. Aneurysm extent was thoracoabdominal aortic aneurysms in 328 patients (71%) and abdominal aortic aneurysms in 135 (29%). Sac shrinkage occurred in 270 patients (58%) and failure to regress in 193 patients (42%), including 19 patients (4%) with sac expansion at 1 year. Patients from both groups had similar cardiovascular risk factors, except for younger age among patients with sac shrinkage (73 ± 8 years vs 75 ± 8 years; P < .001). The median follow-up was 38 months (interquartile range, 18-51 months). The 5-year survival estimate was 69% ± 4.1% for the sac shrinkage group and 46% ± 6.2% for the failure to regress group. Survival estimates adjusted for confounders (age, chronic pulmonary obstructive disease, chronic kidney disease, congestive heart failure, and aneurysm extent) revealed a higher hazard of late mortality in patients with failure to regress (adjusted hazard ratio, 1.72; 95% confidence interval, 1.18-2.52; P = .005). The 5-year cumulative incidences of ARM (1.1% vs 3.1%; P = .30), AAR (0.6% vs 2.6%; P = .20), and aorta-related secondary intervention (17.0% ± 2.8% vs 19.0% ± 3.8%) were both comparable between the groups.

CONCLUSIONS

Aneurysm sac shrinkage at 1 year is common after FB-EVAR and is associated with improved patient survival, whereas sac enlargement affects only a minority of patients. The low incidences of ARM and AAR indicate that failure to regress may serve as a surrogate marker for nonaortic-related death.

One-year follow-up after active aortic aneurysm sac treatment with shape memory polymer devices during endovascular aneurysm repair

OBJECTIVE

To determine the safety and efficacy of treating abdominal aortic aneurysm (AAA) sacs with polyurethane shape memory polymer (SMP) devices during endovascular aneurysm repair (EVAR), using a technique to fully treat the target lumen after endograft placement (aortic flow volume minus the endograft volume). SMP devices self-expand in the sac to form a porous scaffold that supports thrombosis throughout its structure.

METHODS

Two identical prospective, multicenter, single-arm studies were conducted in New Zealand and the Netherlands. The study population was adult candidates for elective EVAR of an infrarenal AAA (diameter of ≥55 mm in men and ≥50 mm in women). Key exclusion criteria were an inability to adequately seal a common iliac artery aneurysm, patent sac feeding vessels of >4 mm, and a target lumen volume of <20 mL or >135 mL. Target lumen volumes were estimated by subtracting endograft volumes from preprocedural imaging-based flow lumen volumes. SMP devices were delivered immediately after endograft deployment via a 6F sheath jailed in a bowed position in the sac. The primary efficacy end point was technical success, defined as filling the actual target lumen volume with fully expanded SMP at the completion of the procedure. Secondary efficacy outcome measures during follow-up were the change in sac volume and diameter, rate of type II endoleak and type I or III endoleaks, and the rate of open repair and related reinterventions, with data collection at 30 days, 6 months, and 1 year (to date). Baseline sac volumes and diameters for change in sac size analyses were determined from 30-day imaging studies. Baseline and follow-up volumes were normalized by subtraction of the endograft volume.

RESULTS

Of 34 patients treated with SMP devices and followed per protocol, 33 patients were evaluable at 1 year. Preprocedural aneurysm volume was 181.4 mL (95% confidence interval [CI], 150.7-212.1 mL) and preprocedural aneurysm diameter was 60.8 mm (95% CI, 57.8-63.9 mm). The target lumen volume was 56.3 mL (95% CI, 46.9-65.8 mL). Technical success was 100% and the ratio of SMP fully expanded volume to estimated target lumen volume was 1.4 ± 0.3. Baseline normalized sac volume and diameter were 140.7 mL (95% CI, 126.6-154.9 mL) and 61.0 mm (95% CI, 59.7-62.3 mm). The adjusted mean percentage change in normalized volume at 1 year was -28.8% (95% CI, -35.3 to -22.3%; P < .001). The adjusted mean change in sac diameter at 1 year was -5.9 mm (95% CI, -7.5 to -4.4 mm; P < .001). At 1 year, 81.8% of patients (95% CI, 64.5%-93.0%) achieved a ≥10% decrease in normalized volume and 57.6% of patients (95% CI, 39.2%-74.5%) achieved a ≥5 mm decrease in diameter. No device- or study procedure-related major adverse events occurred through 1 year after the procedure.

CONCLUSIONS

Treatment of AAA sacs with SMP devices during EVAR resulted in significant sac volume and diameter regression at 1 year with an acceptable safety profile in this prospective study.

Aneurysm Sac Dynamics and its Prognostic Significance Following Fenestrated and Branched Endovascular Aortic Aneurysm Repair

OBJECTIVE

This study aimed to assess aneurysm sac dynamics and its prognostic significance following fenestrated and branched endovascular aneurysm repair (F/BEVAR).

METHODS

Patients undergoing F/BEVAR for degenerative complex aortic aneurysm from 2008 to 2020 at two large vascular centres with two imaging examinations (30 day and one year) were included. Patients were categorised as regression and non-regression, determined by the proportional volume change (> 5%) at one year compared with 30 days. All cause mortality and freedom from graft related events were assessed using Kaplan-Meier methods. Factors associated with non-regression at one year and aneurysm sac volume over time were examined for FEVAR and BEVAR independently using multivariable logistic regression and linear mixed effects modelling.

RESULTS

One hundred and sixty-five patients were included: 122 FEVAR, of whom 34% did not regress at one year imaging (20% stable, 14% expansion); and 43 BEVAR, of whom 53% failed to regress (26% stable, 28% expansion). Following F/BEVAR, after risk adjusted analysis, non-regression was associated with higher risk of all cause mortality within five years (hazard ratio [HR] 2.56, 95% confidence interval [CI] 1.09 - 5.37; p = .032) and higher risk of graft related events within five years (HR 2.44, 95% CI 1.10 - 5.26; p = .029). Following multivariable logistic regression, previous aortic repair (odds ratio [OR] 2.56, 95% CI 1.11 - 5.96; p = .029) and larger baseline aneurysm diameter (OR/mm 1.04, 95% CI 1.00 - 1.09; p = .037) were associated with non-regression at one year, whereas smoking history was inversely associated with non-regression (OR 0.21, 95% CI 0.04 - 0.96; p = .045). Overall following FEVAR, aneurysm sac volume decreased significantly up to two years (baseline vs. two year, 267 [95% CI 250 - 285] cm3vs. 223 [95% CI 197 - 248] cm3), remaining unchanged thereafter. Overall following BEVAR, aneurysm sac volume remained stable over time.

CONCLUSION

Like infrarenal EVAR, non-regression at one year imaging is associated with higher five year all cause mortality and graft related events risks after F/BEVAR. Following FEVAR for juxtarenal aortic aneurysm, aneurysm sacs generally displayed regression (66% at one year), whereas after BEVAR for thoraco-abdominal aortic aneurysm, aneurysm sacs displayed a concerning proportion of growth at one year (28%), potentially suggesting a persistent risk of rupture and consequently requiring intensified surveillance following BEVAR. Future studies will have to elucidate how to improve sac regression following complex EVAR, and whether the high expansion risk after BEVAR is due to advanced disease extent.

Importance of sac regression after EVAR and the role of EndoAnchors

The initial success and widespread adoption of endovascular aneurysm repair (EVAR) for the treatment of abdominal aortic aneurysms have been tempered by numerous reports of secondary interventions and increased long-term mortality compared with open repair. Over the past decade, several studies on postoperative sac dynamics after EVAR have suggested that the presence of sac regression is a benign feature with a favorable prognosis. Conversely, increasing sacs and even stable sacs can be indicators of more unstable sac behavior with worse outcomes in the long-term. Endoleaks were initially perceived as the main drivers of sac behavior. However, the observation that sac regression can occur in the presence of endoleaks, and vice versa - increasing sacs without evidence of endoleak - on imaging studies, suggests the involvement of other contributing factors. These factors can be divided into anatomical factors, patient characteristics, sac thrombus composition, and device-related factors. The shift of interest away from especially type 2 endoleaks is further supported by promising results with the use of EndoAnchors regarding postoperative sac behavior. This review provides an overview of the existing literature on the implications and known risk factors of post-EVAR sac behavior, describes the accurate measurement of sac behavior, and discusses the use of EndoAnchors to promote sac regression.

Time Dependent Correlation Between Sac Behaviour and Re-intervention after Endovascular Aneurysm Repair

OBJECTIVE

This study aimed to investigate the correlation between aneurysm sac behaviour and time to re-intervention after endovascular aneurysm repair (EVAR).

METHODS

A retrospective observational cohort study of patients who underwent EVAR at a single centre between January 2008 and November 2011 and who were followed up for a mean of 6.6 ± 2.9 years was conducted. Based on sac appearances on pre-operative imaging and imaging at the end of follow up, patients were stratified into two groups: (1) sac regression; and (2) no sac regression. The no sac regression group was further subdivided into stable sac group and sac expansion group. Sac regression and expansion throughout follow up were defined as a decrease or increase in the abdominal aortic aneurysm sac diameter of ≥ 5 mm compared with the pre-operative size. A Cox proportional hazards model using multiple failure per subject data was used to identify sac behaviour as a predictor of re-intervention free time.

RESULTS

Patients with sac regression had a higher probability of freedom from re-intervention compared with those with a stable or expanding aneurysm sac (94%, 57%, and 16% at 12 years, respectively; log rank, p < .001). Mean time to re-intervention was 11.3 years for the sac regression group, 8.8 years for the stable sac group, and 5.0 years for the sac expansion group (p < .001). In the stable sac group, the risk of re-intervention increased sharply six years after EVAR, whereas in the sac expansion group a sharp rise in re-intervention was noted 3.5 years after EVAR, reaching a plateau after year 6.

CONCLUSION

A time dependent correlation between aneurysm sac behaviour and re-intervention was found. Such findings have implications for surveillance strategies.

One-year aneurysm-sac dynamics are associated with reinterventions and rupture following infrarenal endovascular aneurysm repair

OBJECTIVE

One-year aneurysm sac changes have previously been found to be associated with mortality and may have the potential to guide personalized follow-up following endovascular aneurysm repair (EVAR). In this study, we examined the association of these early sac changes with long-term reintervention and rupture.

METHODS

We identified all patients undergoing first-time EVAR for intact abdominal aortic aneurysm between 2003 and 2018 in the Vascular Quality Initiative with linkage to Medicare claims for long-term outcomes. We included patients with an imaging study at 1 year postoperatively. Aneurysm sac behavior was defined as per the Society for Vascular Surgery guidelines: stable sac (<5 mm change), sac regression (≥5 mm), and sac expansion (≥5 mm). Outcomes included mortality, reintervention, and rupture within 8 years, which were assessed with Kaplan-Meier methods and multivariable Cox regression analysis. Secondarily, we utilized polynomial spline interpolation to demonstrate the continuous relationship of diameter change to 8-year hazard of reintervention, rupture, or mortality as a composite outcome.

RESULTS

Of 31,185 EVAR patients, 16,102 (52%) had an imaging study at 1 year and were included in this study. At 1 year, 44% of sacs remained stable, 49% regressed, and 6.2% displayed expansion. Following risk adjustment, compared with a stable sac at 1 year, sac regression was associated with lower 8-year mortality (49% vs 53%; hazard ratio [HR], 0.92; 95% confidence interval [CI], 0.85-0.99; P = .036), reintervention rate (8.9% vs 15%; HR, 0.58; 95% CI, 0.50-0.68; P < .001), and rupture rate (2.0% vs 4.0%; HR, 0.45; 95%CI, 0.29-0.69; P < .001). Conversely, compared with a stable sac, sac expansion was associated with higher 8-year mortality (64% vs 53%; HR, 1.31; 95% CI, 1.14-1.51; P < .001) and reintervention rate (27% vs 15%; HR, 1.98; 95% CI, 1.57-2.51; P < .001), but similar risk of rupture (7.2% vs 4.0%; HR, 1.61; 95% CI, 0.88-2.96; P = .12). Polynomial spline interpolation demonstrated that, compared with no diameter change at 1 year, increased sac regression was associated with an incrementally lower risk of late outcomes, whereas increased sac expansion was associated with an incrementally higher risk of late outcomes.

CONCLUSIONS

Following EVAR, compared with a stable sac at 1-year imaging, sac regression and expansion are associated with a lower and higher risk respectively of long-term mortality, reinterventions, and ruptures. Moreover, the amount of regression or expansion seems to be incrementally associated with these late outcomes, too. Future studies are needed to determine how to improve 1-year sac regression, and whether it is safe to extend follow-up intervals for patients with regressing sacs.

Editor's Choice -- European Society for Vascular Surgery (ESVS) 2024 Clinical Practice Guidelines on the Management of Abdominal Aorto-Iliac Artery Aneurysms

OBJECTIVE

The European Society for Vascular Surgery (ESVS) has developed clinical practice guidelines for the care of patients with aneurysms of the abdominal aorta and iliac arteries in succession to the 2011 and 2019 versions, with the aim of assisting physicians and patients in selecting the best management strategy.

METHODS

The guideline is based on scientific evidence completed with expert opinion on the matter. By summarising and evaluating the best available evidence, recommendations for the evaluation and treatment of patients have been formulated. The recommendations are graded according to a modified European Society of Cardiology grading system, where the strength (class) of each recommendation is graded from I to III and the letters A to C mark the level of evidence.

RESULTS

A total of 160 recommendations have been issued on the following topics: Service standards, including surgical volume and training; Epidemiology, diagnosis, and screening; Management of patients with small abdominal aortic aneurysm (AAA), including surveillance, cardiovascular risk reduction, and indication for repair; Elective AAA repair, including operative risk assessment, open and endovascular repair, and early complications; Ruptured and symptomatic AAA, including peri-operative management, such as permissive hypotension and use of aortic occlusion balloon, open and endovascular repair, and early complications, such as abdominal compartment syndrome and colonic ischaemia; Long term outcome and follow up after AAA repair, including graft infection, endoleaks and follow up routines; Management of complex AAA, including open and endovascular repair; Management of iliac artery aneurysm, including indication for repair and open and endovascular repair; and Miscellaneous aortic problems, including mycotic, inflammatory, and saccular aortic aneurysm. In addition, Shared decision making is being addressed, with supporting information for patients, and Unresolved issues are discussed.

CONCLUSION

The ESVS Clinical Practice Guidelines provide the most comprehensive, up to date, and unbiased advice to clinicians and patients on the management of abdominal aorto-iliac artery aneurysms.

Prevalence of type II endoleak after elective endovascular aneurysm repair with polytetrafluoroethylene- or polyester-based endografts

OBJECTIVE

Type II endoleak is the most frequent complication after endovascular abdominal aneurysm repair. Polytetrafluoroethylene and polyester (PE) are the two most commonly used graft materials in endovascular aneurysm repair (EVAR) devices. Biological properties of the material might influence the appearance and persistence of type II endoleak (T2EL). Therefore, the aim of this study was to evaluate potential differences in the prevalence of T2EL after EVAR between polytetrafluoroethylene (PTFE) and PE endografts in patients electively treated for an infrarenal abdominal aortic aneurysm.

METHODS

A single-center, retrospective, observational study was conducted between January 2011 and January 2022. Preoperative, procedural, and follow-up data were derived from electronic health records. Imaging included computed tomography scans, and/or duplex ultrasound examination. The primary end point was the prevalence of T2EL diagnosed within 1 year after EVAR. Secondary end points included the prevalence of T2EL throughout follow-up, early (≤30 days) and late (>30 days) T2EL, the rate of T2EL disappearance during the follow-up period, the prevalence of type I and III endoleak, and T2EL-related reinterventions.

RESULTS

Follow-up was available for 394 patients, 245 in the PE and 149 in the PTFE group. The prevalence of T2EL diagnosed within 1 year after endovascular repair was 11.8% in the PE group and 21.5% in the PTFE group (P = .010). There was no significant difference in early (≤30 days) and late (>30 days) T2EL between groups (P = .270 and P = .311). There was no difference in the freedom from endoleak type II reinterventions between groups (P = .877).

CONCLUSIONS

The prevalence of T2EL after elective EVAR is significantly higher with the use of PTFE-based endografts compared with PE-based endografts. This difference is mostly based on T2EL diagnosed after 30 days of follow-up.

Factors Influencing on the Aneurysm Sac Shrinkage after Endovascular Abdominal Aortic Aneurysm Repair by the Analysis of the Patients with the Aneurysm Sac Shrinkage and Expansion

Objectives: The aneurysmal sac shrinkage has been reported as the strong predictor of favorable long-term outcome after endovascular aneurysm repair (EVAR). We evaluated the effects of perioperative and intraoperative factors on the aneurysm sac shrinkage. Methods: EVAR was performed for 296 patients during August 2009-December 2021. Nine patients with type Ia, Ib, or III; 69 patients with the sac diameter change less than 5 mm; and five patients with sac re-expansion after shrunk more than 5 mm were excluded. Thus, patients with sac shrinkage 5 mm or more (79 patients, shrinkage group) and with sac expansion 5 mm or more (18 patients) were included in this study. Antifibrinolytic therapy with tranexamic acid (TXA) 1500 mg/day for 6 months after EVAR was introduced in March 2013 and patent aortic side branches were coil embolized during EVAR since July 2015. Patients' background and patent aortic side branches at the end of EVAR were evaluated. Results: Univariate analysis for comparison between patients with sac shrinkage and sac expansion revealed that males (82.3% vs. 55.6%, p = 0.021), without antiplatelet therapy (40.5% vs. 66.7%, p = 0.044) and TXA (79.8% vs. 38.9%, p <0.001), were significantly associated with sac shrinkage. By multivariate analysis, the odds ratio of sac shrinkage was 11.7 for males, 0.1 for the patients on antiplatelet therapy, and 6.5 for the patient who received TXA. The patients with patent inferior mesenteric artery (IMA) were less in the shrinkage group (20.3% vs. 77.8%, p <0.001) and with two or less patent lumbar arteries (LAs) were more in the shrinkage group (82.3% vs. 33.3%, p < 0.001). The odd ratio of sac shrinkage was 7.8 for occluded IMA and 3.9 for two or less patent LAs. Conclusion: The possibility of sac shrinkage would be high for the patient with occluded IMA and two or less patent LA at the end of EVAR, and that patient received TXA after EVAR. (This is a translation of Jpn J Vasc Surg 2022; 31: 291-297.).

Factors associated with all-cause mortality following endovascular abdominal aortic aneurysm repair

Background: Knowledge of factors that influence all-cause mortality after endovascular abdominal aortic aneurysm repair (EVAR) could improve therapeutic strategies post-EVAR and thus patient prognosis. Our study aimed to evaluate the association between sociodemographic information, comorbidities, laboratory parameters, treatment, selected anatomical and genetic factors and all-cause mortality post-EVAR. Patients and methods: We reviewed all patients who had undergone elective EVAR for non-ruptured abdominal aortic aneurysm (AAA) between January 2010 and December 2019. AAA size (maximum diameter and volume) was measured using CT-angiography. Sac expansion was defined as at least 5 mm increase, sac regression as at least 5 mm decrease in the sac diameter determined at 36±3 months post-EVAR in relation to pre-EVAR AAA diameter. Adjustments were performed for age, hypertension, diabetes mellitus, dyslipidaemia, sex, smoking, number of lumbar arteries, patency of inferior mesenteric artery and number of reinterventions post-EVAR. Results: One hundred and sixty-two patients (150 men, 12 women) with a mean age of 72.6±7.3 years were included in the analysis. Pre-EVAR AAA diameter (HR 1.07; 95% CI 1.03 - 1.12; p=0.001), pre-EVAR AAA volume (HR 1.01; 95% CI 1.002 - 1.011; p=0.008), post-EVAR sac diameter (HR 1.06; 95% CI 1.03 - 1.10; p=0.000), post-EVAR sac volume (HR 1.01; 95% CI 1.002 - 1.011; p=0.006) and anticoagulation therapy (HR 2.46; 95% CI 1.18 - 5.14; p=0.019) were associated with higher mortality in multivariate analysis. Sac regression (HR 0.42; 95% CI 0.22 - 0.82; p=0.011), and treatment with angiotensin-converting enzyme (ACE) inhibitors or angiotensin II receptor blockers (ARBs) (HR 0.71; 95% CI 0.36 - 0.97; p=0.047) were associated with lower mortality. Conclusions: Greater pre- and post-EVAR diameter and volume, failure of sac regression and anticoagulation were associated with higher mortality post-EVAR. Reduced mortality was observed in patients treated with ACE inhibitors or ARBs, and in patients with AAA sac regression.

Correlative effect between sac regression and patient longevity following endovascular solution for abdominal aortic aneurysms: an international analysis

INTRODUCTION

Since the introduction of endovascular aortic repair (EVAR) it has become the mainstay treatment for abdominal aortic aneurysms. Several EVAR devices exist commercially, yet, the Terumo Aortic Fenestrated Anaconda™ endograft has demonstrated outstanding results. Evidence in the literature suggests that sac regression could be linked to patient survival and longevity. The main scope of this study is to evaluate sac regression and survival achieved using the Fenestrated Anaconda™ endograft and to discuss relevant literature.

MATERIALS AND METHODS

The current study represents a nine-year cross-sectional international analysis of custom-made Fenestrated Anaconda™ device. For the statistical analysis, SPSS 28 for Windows and R were utilised. Pearson chi-square analysis was used to assess differences in cumulative distribution frequencies between select variables. Statistical significance for all two-tailed tests was set at p < 0.05.

RESULTS

A total of 5,058 patients received the Fenestrated Anaconda™ in this study, either due to unsuitable/complex anatomy for competitor devices (n = 3,891) or based on surgeon preference (n = 1,167). A sac regression of 0-30% was observed in 4,772 (94.3%) over the first four years post-EVAR. Here, 99.6% of patients receiving the Fenestrated Anaconda™ due to unsuitable/complex anatomy for competitor devices and 76.8% based on surgeon preference had 0-30% sac regression. During years 5-9 of follow-up, all patients had 20-45% sac regression. Patient survival during the first six years post-EVAR was 100% but dropped to 77.1% in years 7-9. Survival differed between categorical patient subsets based on the indication.

DISCUSSION

The Fenestrated Anaconda™ has been proven to be a highly effective EVAR endograft. Evidence in the literature clearly demonstrates that sac regression is an accurate prognostic factor for patient survival and longevity.

Outcomes of Endurant II Stent Graft According to Anatomic Severity Grade Score

OBJECTIVES

This study's objective was to evaluate Endurant II (Medtronic Inc, Minneapolis, Minnesota) stent graft's early and midterm outcomes and compare the results according to the anatomic severity grade (ASG) scores.

METHODS

This was a retrospective study of patients treated with the Endurant II stent graft between January 2013 and May 2021. The patients were divided into 2 independent groups, including those with a low ASG score (score <14) and a high ASG score (score >14).

RESULTS

A total of 165 consecutive patients (89% males, age 74±8 years) were included. There were 110 (67%) patients in the low-score group and 55 (33%) patients in the high-score group. Technical success was achieved in all cases. Primary clinical success at 30 days was 100% and at 1 year was 96%. Median operative time was longer in the high-score group with no statistical significance (133 vs 120 minutes, p=0.116). The median dose area product of low-score patients (50.9 Gy·cm2; IQR 22.4-75.5 Gy·cm2) was significantly lower than high-score patients (85.0 Gy·cm2; IQR 46.5-127.9 Gy·cm2) with p=0.025. Median fluoroscopic time was lower in low-score patients (17 minutes; IQR 13-24 minutes) compared with high-score patients (19 minutes; IQR 16-23 minutes) without a significant difference at p=0.148. At a midterm follow-up of 32 months (range 2-63 months), combined complications (29% vs 8%, p<0.001) and implant-related complications (13% vs 4%, p=0.043) were higher in the high-score group. Systemic complications at 30 days were higher in the high-score group without a statistically significant difference (15% vs 11%, p=0.500). The Kaplan-Meier estimate of freedom from reintervention was significantly higher in the low-risk group at 1 (97% vs 90%), 2 (96% vs 88%), and 3 years (96% vs 85%) with (p=0.035). The cumulative survival rate was significantly higher in the low-score group than high-score group (p=0.001) at 1 (99% vs 87%), 2 (98% vs 85%), and 3 years (96% vs 82%).

CONCLUSIONS

Endurant II endovascular aneurysm repair seems to be safe in both low-score and high-score patients. However, patients in the high-score group showed more implant-related complications and midterm mortalities than those in the low-score group.

Biomechanics and Early Sac Regression after Endovascular Aneurysm Repair of Abdominal Aortic Aneurysm

Background

Sac regression after endovascular aneurysm repair (EVAR) of abdominal aortic aneurysms (AAA) is regarded as a marker of successful response to treatment. Several factors influence sac behavior after EVAR, yet little is known about the value of preoperative biomechanics. The aim of this study was to investigate the difference in aortic biomechanics between patients with and without sac regression.

Methods

Patients treated with standard EVAR for infrarenal AAA at the Karolinska University Hospital between 2009 and 2012 with one preoperative and a minimum of two postoperative computed tomography angiography (CTA) scans were considered for inclusion in this single-center retrospective cohort study. Biomechanical indices such as AAA wall stress and wall stress-strength ratio as well as intraluminal thrombus (ILT) thickness and stress were measured preoperatively in A4ClinicRE (VASCOPS GmbH). AAA diameter and volume were analyzed on preoperative, 30-day, and 1-year CTAs. Patients were dichotomized based on sac regression, defined as a ≥ 5 mm decrease in maximal AAA diameter between the first two postoperative CTA scans. Multivariable logistic regression was used for analysis of factors associated with early sac regression.

Results

Of the 101 patients treated during the inclusion period, 64 were included. Thirty-nine (61%) demonstrated sac regression and 25 (39%) had a stable sac or sac increase. The mean patients age (73 years vs 76 years), male sex (85% vs 96%), and median AAA diameter (58 mm vs 58.5 mm) did not differ between patients with and without sac regression. Although no difference in preoperative biomechanics was seen between the groups, multivariable logistic regression revealed that a larger AAA diameter (odds ratio [OR], 1.27; 95% confidence interval [CI], 1.06-1.51; P = .009) and smoking (OR, 22.1; 95% CI, 2.78-174; P = .003) were positively associated with sac regression. In contrast, the lumen diameter (OR, 0.87; 95% CI, 0.77-0.98; P = .023), ILT thickness (OR, 0.85; 95% CI, 0.75-0.97; P = .013), aspirin or direct-acting oral anticoagulant use (OR, 0.11; 95% CI, 0.02-0.61; P = .012), and mean ILT stress (OR, 0.35; 95% CI, 0.14-0.87; P = .024) showed a negative association. Patients with sac regression had fewer reinterventions (log-rank P = .010) and lower mortality (log-rank P = .012) at the 5-year follow-up.

Conclusions

This study, characterizing preoperative biomechanics in patients with and without sac regression, demonstrated a negative association between mean ILT stress and ILT thickness with a change in sac diameter after EVAR. Given that the ILT is a highly dynamic entity, further studies focusing on the role of the thrombus are needed. Furthermore, patients presenting with early sac regression had improved outcomes after EVAR.

Risk factors, risk stratification and risk-specific surveillance strategies after endovascular aneurysm repair: study protocol for a Delphi study by the International RIsk Stratification in EVAR (IRIS-EVAR) working group

INTRODUCTION

Several risk factors for adverse events after endovascular aneurysm repair (EVAR) have been described, but there is no consensus on their comparative prognostic significance, use in risk stratification and application in determining postoperative surveillance.

METHODS AND ANALYSIS

A scoping review of the literature was conducted to identify risk factors for adverse events after EVAR. Main adverse events were considered post-EVAR abdominal aortic aneurysm rupture and reintervention. Risk factors were grouped into four domains: (1) preoperative anatomy, (2) aortic device, (3) procedure performance and (4) postoperative surveillance. The Delphi methodology will be used to steer a group of experts in the field towards consensus organised into three tiers. In tier 1, participants will be asked to independently rate risk factors for adverse events after EVAR. In tier 2, the panel will be asked to independently rate a range of combinations of risk factors across the four domains derived from tier 1. A risk-stratification tool will then be built, which will include algorithms that map responses to signalling questions onto a proposed risk judgement for each domain. Domain-level judgements will in turn provide the basis for an overall risk judgement for the individual patient. In tier 3, risk factor-informed surveillance strategies will be developed. Each tier will typically include three rounds and rating will be conducted using a 4-point Likert scale, with an option for free-text responses.

ETHICS AND DISSEMINATION

Research Ethics Committee and Health Research Authority approval has been waived, since this is a professional staff study and no duty of care lies with the National Health Service to any of the participants. The results will be presented at regional, national and international meetings and will be submitted for publication in peer-reviewed journals. The risk stratification tool and surveillance algorithms will be made publicly available for clinical use and validation.

Predictors of Abdominal Aortic Aneurysm Shrinkage after Endovascular Repair

Recent studies demonstrate that patients with a shrinking abdominal aortic aneurysm (AAA), one-year after endovascular repair (EVAR), have better long-term outcomes than patients with a stable AAA. It is not known what factors determine whether an AAA will shrink or not. In this study, a range of parameters was investigated to identify their use in differentiating patients that will develop a shrinking AAA from those with a stable AAA one-year after EVAR. Hundred-seventy-four patients (67 shrinking AAA, 107 stable AAA) who underwent elective, infrarenal EVAR were enrolled between 2011-2018. Long-term survival was significantly better in patients with a shrinking AAA, compared to those with a stable AAA (p = 0.038). Larger preoperative maximum AAA diameter was associated with an increased likelihood of developing AAA shrinkage one-year after EVAR-whereas older age and larger preoperative infrarenal β angle were associated with a reduced likelihood of AAA shrinkage. However, this multivariate logistic regression model was only able to correctly identify 66.7% of patients with AAA shrinkage from the total cohort. This is not sufficient for implementation in clinical care, and therefore future research is recommended to dive deeper into AAA anatomy, and explore potential predictors using artificial intelligence and radiomics.

A stable aneurysm sac after endovascular aneurysm repair as a predictor for mortality, an in-depth analysis

OBJECTIVES

The aim of this study was to compare the long-term survival in patients with a stable aneurysmal sac and those with aneurysmal sac regression after endovascular aneurysm repair (EVAR) and to identify independent risk factors for aneurysmal sac regression and mortality after EVAR.

METHODS

We reviewed all patients who underwent EVAR between 2005 and 2018 with a computed tomography angiography available at 1-year follow-up. Aneurysm sac regression was defined as a diameter decrease of more than 10%. We used a multivariable regression to identify independent risk factors for sac regression. Kaplan-Meier analysis and Cox regression were done to test differences in 5-year mortality between a stable sac and sac regression.

RESULTS

The inclusion criteria were met by 325 patients, 185 in the sac regression group and 140 in the stable sac group. Multivariable logistic regression analysis showed that treatment for a ruptured aneurysm was an independent risk factor for aneurysmal sac regression (hazard ratio [HR], 0.26; 95% confidence interval [CI], 0.07-0.96). Age (HR, 1.05; 95% CI, 1.01-1.09), ischemic heart disease (HR, 1.94; 95% CI, 1.13-3.31), neck thrombus (HR, 2.72; 95% CI, 1.07-6.95), and a type II endoleak (HR, 19.21; 95% CI, 7.32-50.40) were independent risk factors for a stable aneurysm sac diameter. Multivariable Cox regression showed a significantly increased risk of mortality for patients with a stable aneurysm sac after EVAR (odds ratio, 2.25; 95% CI, 1.36-3.72). There was no significant difference in cause of death between the two groups.

CONCLUSION

A stable aneurysm sac after EVAR is associated with increased mortality. Age, ischemic heart disease, neck thrombus, and a type II endoleak are independent risk factors for a stable sac. However, a well-founded explanation for this finding is still lacking. Future research should be focussed on aggressive treatment of type II endoleaks and inflammatory processes as potential pathophysiological mechanisms.

Longer follow-up intervals following EVAR are safe and appropriate after marked aneurysm sac regression

BACKGROUND

Abdominal aortic aneurysm (AAA) shrinkage after endovascular aortic aneurysm repair (EVAR) is a surrogate marker for successful exclusion. Our study characterized aneurysm sac remodeling after EVAR to identify a pattern that may be associated with benign AAA behavior and would safely allow a less rigorous follow-up regimen after EVAR.

METHODS

Elective infrarenal EVARs performed between 2008 and 2011 at our institution were retrospectively reviewed. AAA sac diameters using the minor axis measurement from ultrasound imaging or computer tomography angiogram imaging were compared with the baseline diameter from the 1-month postoperative computer tomography angiogram. The primary outcome was a composite of freedom from postoperative reintervention or rupture. We compared those with AAA sacs who regressed to predefined minimum diameter thresholds with those who did not. Outcomes were plotted with Kaplan-Meier curves and compared using log-rank testing and Fine-Gray regression using death as a competing risk, clustered on graft type. For patients whose AAA reached the minimum sac diameter, landmark analysis evaluated ongoing size changes including further regression and sac re-expansion.

RESULTS

A total of 540 patients (aged 75.1 ± 8.2 years; 82.0% male) underwent EVAR with an average preoperative AAA size of 55.2 ± 11.5 mm. The median postoperative follow-up was 5.3 years (interquartile range, 1.4-8.7 years) during which 64 patients underwent reintervention and 4 ruptured. AAA sac regression to ≤40 mm in diameter was associated with improved freedom from reintervention or rupture overall (log-rank, P < .01), which was maintained after controlling for the competing risk of death (P < .01). In 376 patients (70%) whose aneurysm sac remained >40 mm, 99 reinterventions were performed on 63 patients. Of 166 (31%) patients whose sac regressed to ≤40 mm, only 1 patient required a reintervention, and no one ruptured. The mean time to a diameter of ≤40 mm was 2.3 ± 1.9 years. Only eight patients (5%) developed sac re-expansion to >45 mm; all but two occurred at least 3 years after initially regressing to ≤40 mm.

CONCLUSIONS

In long-term follow-up, patients whose minimum AAA sac diameter regressed ≤40 mm after EVAR experienced a very low rate of reintervention, rupture, or sac re-expansion. Most sac re-expansion occurred at least 3 years after reaching this threshold and did not result in clinical events. Increasing follow-up frequency up to 3-year intervals once the AAA sac regresses to 40 mm would carry minimal risk of aneurysm-related morbidity.

Predictors of sac regression after fenestrated endovascular aneurysm repair

OBJECTIVE

Aneurysm sac regression after standard endovascular aortic repair is associated with improved outcomes, but similar data are limited after fenestrated endovascular aortic repair (FEVAR). We sought to evaluate sac regression after FEVAR, and identify any predictors of this favorable outcome.

METHODS

Patients undergoing elective FEVAR using the commercially available Zenith Fenestrated device (ZFEN; Cook Medical, Bloomington, IN) from 2012 to 2018 at a single institution were reviewed retrospectively. The maximal aortic diameter was compared between the preoperative scan and those obtained in follow-up. Patients with of 5 mm or more sac regression were included in the regression (REG) group, with all others in the nonregression (NONREG) group. Outcomes were compared between groups using univariate analysis, and logistic regression analysis was performed to identify any predictive factors for sac regression.

RESULTS

We included 132 patients undergoing FEVAR in the analysis. At a mean follow-up of 33.1 months, 65 patients (49.2%) had sac regression of 5 mm or more and comprised the REG group (n = 65 [49.2%]). The REG group had smaller diameter devices, and were less likely to have had concomitant chimney grafts placed (P < .05). The NONREG group had a higher incidence of type II endoleak (35.8% vs 12.3%; P = .002). Sac regression was associated with a significant mortality benefit on Kaplan-Meier analysis (log rank P = .02). Multivariate analysis identified adjunctive parallel grafting (odds ratio [OR], 0.01; 95% confidence interval [CI], 0.03-0.36; P < .01), persistent type II endoleak (OR, 0.13; 95% CI, 0.02-0.74; P < .01), and a greater number of target vessels (OR, 0.25; 95% CI, 0.10-0.62; P = .002) as independent predictors of failure to regress.

CONCLUSIONS

Sac regression after FEVAR occurred in nearly one-half of patients, but seems to be less common in patients with persistent type II endoleaks and those undergoing concomitant parallel grafting. Sac regression was associated with a significant survival advantage, and can be used as a clinical marker for success after FEVAR.