Risk Analysis of Aneurysm Sac Enlargement Caused by Type II Endoleak after Endovascular Aortic Repair

Endovascular repair of abdominal aortic aneurysm-related type II endoleak: a multicenter study on the possibility of further intervention

Background

We aimed to analyze the risk factors associated with Type II endoleak (T2EL) requiring reintervention after endovascular aneurysm repair (EVAR) for multicenter abdominal aortic aneurysms.

Methods

A retrospective analysis was conducted on data from 614 patients with abdominal aortic aneurysms who underwent elective EVAR at three centers (Tianjin Medical University General Hospital, Affiliated Hospital of Inner Mongolia Medical University, Shanxi Provincial People's Hospital) from January 2017 to December 2021. After applying exclusion criteria, 375 patients were included in the study, with 50 patients in the T2EL-related reintervention group and 325 patients in the non-T2EL group. Single-factor and multiple-factor logistic analyses were used to identify high-risk factors, and ROC curve analysis was performed to determine the risk thresholds for mesenteric artery diameter, number of lumbar arteries, maximum aneurysm diameter, and proportion of intraluminal thrombus volume.

Results

The rate of T2EL-related reintervention among the 375 patients was 13.33% (50/375). Single-factor analysis indicated that age, hypertension, maximum aneurysm diameter, proportion of intraluminal thrombus, diameter of inferior mesenteric artery (IMA), and number of patent lumbar arteries (LA) were risk factors for T2EL-related reintervention. Multiple-factor logistic analysis identified maximum aneurysm diameter, proportion of thrombus, IMA diameter, and number of patent LA as the main influencing factors for T2EL-related reintervention after EVAR. Significant risk factors for reintervention were maximum aneurysm diameter (OR = 1.043, 95% CI 1.015-1.072, P = 0.002), IMA diameter (OR = 3.901, 95% CI 1.116-13.632, P = 0.033), and number of LA (OR = 2.584, 95% CI 1.722-3.769, P < 0.001). A significant protective factor for reintervention was thrombus proportion (OR = 0.895, 95% CI 0.864-0.927, P < 0.001). ROC curve analysis showed that the risk thresholds for reintervention were an IMA diameter of 2.95 mm, intraluminal thrombus volume proportion <42.5%, number of LA ≤5.5, and aneurysm diameter of 53.55 mm.

Conclusion

Cases with identified risk factors are considered to have a higher risk of T2EL-related reintervention after EVAR. Exceeding the new risk thresholds may indicate a higher likelihood of T2EL-related reintervention after EVAR.

Endovascular Abdominal Aortic Aneurysm Repair

A great majority of abdominal aortic aneurysm are treated with endovascular aortic repair (EVAR) in current practice. EVAR has lower peri-procedural mortality and morbidity compared to open surgical repair. Anatomic factors such as aneurysm neck morphology, iliac anatomy, and access vessel anatomy need careful assessment for the successful performance of EVAR. Evolving technology and techniques are allowing more patients to be treated with EVAR with better long-term outcomes.

Identifying Patients at High Risk for Post-EVAR Aneurysm Sac Growth

PURPOSE

Post-EVAR (endovascular aneurysm repair) aneurysm sac growth can be seen as therapy failure as it is a risk factor for post-EVAR aneurysm rupture. This study sought to identify preoperative patient predictors for developing post-EVAR aneurysm sac growth.

MATERIAL AND METHODS

A systematic review was conducted to select potential predictive preoperative factors for post-EVAR sac growth (including a total of 34.886 patients), which were evaluated by a retrospective single-center analysis of patients undergoing EVAR between 2009 and 2019 (N=247) with pre-EVAR computed tomography scans and at least 1 year follow-up. The primary study outcome was post-EVAR abdominal aortic aneurysm (AAA) sac enlargement (≥5 mm diameter increase). Multivariate Cox regression and Kaplan-Meier survival curves were constructed.

RESULTS

Potential correlative factors for post-EVAR sac growth included in the cohort analysis were age, sex, anticoagulants, antiplatelets, renal insufficiency, anemia, low thrombocyte count, pulmonary comorbidities, aneurysm diameter, neck diameter, neck angle, neck length, configuration of intraluminal thrombus, common iliac artery diameter, the number of patent lumbar arteries, and a patent inferior mesenteric artery. Multivariate analysis showed that infrarenal neck angulation (hazard ratio, 1.014; confidence interval (CI), 1.001-1.026; p=0.034) and the number of patent lumbar arteries (hazard ratio, 1.340; CI, 1.131-1.588; p<0.001) were associated with post-EVAR growth. Difference in estimated freedom from post-EVAR sac growth for patients with ≥4 patent lumbar arteries versus <4 patent lumbar arteries became clear after 2 years: 88.5% versus 100%, respectively (p<0.001). Of note, 31% of the patients (n=51) with ≥4 patent lumbar arteries (n=167) developed post-EVAR sac growth. In our cohort, the median maximum AAA diameter was 57 mm (interquartile range [IQR] = 54-62) and the median postoperative follow-up time was 54 months (IQR = 34-79). In all, 23% (n=57) of the patients suffered from post-EVAR growth. The median time for post-EVAR growth was 37 months (IQR = 24-63). In 46 of the 57 post-EVAR growth cases (81%), an endoleak was observed; 2.4% (n=6) of the patients suffered from post-EVAR rupture. The total mortality in the cohort was 24% (n=60); 4% (n=10) was AAA related.

CONCLUSIONS

This study showed that having 4 or more patent lumbar arteries is an important predictive factor for postoperative sac growth in patients undergoing EVAR.

CLINICAL IMPACT

This study strongly suggests that having 4 or more patent lumbar arteries should be included in preoperative counseling for EVAR, in conjunction to the instructions for use (IFU).

Prospective evaluation of automated vascular analysis for ilio-femoral artery lesions before and after percutaneous endovascular aortic repair

BACKGROUND

This study was conducted to evaluate the differences between pre- and postoperative access conditions in percutaneous endovascular aortic repair (PEVAR).

METHODS

Between December 2021 and October 2023, PEVAR was performed on 61 patients using the Perclose ProStyle (Abbott Vascular). Enhanced computed tomography and ankle-brachial index tests were performed preoperatively and postoperatively. The inner diameter and area of the iliofemoral artery were automatically measured, and the pre- and postoperative values were compared (114 legs). The same analysis was performed on 12 legs with previous groin operations; open surgical EVAR was performed in 9 legs, an endarterectomy of the femoral artery in 1, and a femoropopliteal bypass in the other leg.

RESULTS

All patients were discharged without surgical site infections, lymphatic fistulas, or retroperitoneal haematomas. There were no significant differences between the pre-and postoperative inner diameter and inner area of the external iliac artery and common femoral artery. There were no significant differences between the preoperative and postoperative ankle-brachial index tests. In 12 legs with a previous groin operation, the postoperative ankle-brachial index tests and inner diameter and area of the external iliac artery and common femoral artery were statistically equal to the preoperative values.

CONCLUSIONS

This study can support the safety of percutaneous endovascular aortic repair, even in patients with redo groin operations.

Early and Mid-Term Outcomes of Transcaval Embolization for Type 2 Endoleak after Endovascular Aortic Repair

Background: Among the endovascular approaches for the management of endoleak type 2 (EL 2), transcaval embolization (TCE) has shown encouraging outcomes. However, the literature is still limited. This study aimed to present the early and mid-term outcomes of TCE for EL 2 after endovascular aortic repair. Methods: A retrospective, single-center analysis of consecutive patients managed with TCE for EL 2 after standard or complex endovascular aortic repair, from August 2015 to March 2024, was conducted. The indication for TCE was the presence of an EL 2 related to ≥5 mm sac increase, compared to the first imaging after aneurysm exclusion or the smallest diameter during follow-up. Patients managed with TCE for other types of endoleaks were excluded. The primary outcomes were technical and clinical successes during follow-up. Results: Forty-three patients were included (mean age: 75.1 ± 6.0 years, 90.7% males). Technical success was 97.7%. Selective embolization was performed in 48.8% and non-selective in 51.2%. No death was recorded at 30 days. The estimated clinical success was 90.0% (standard error; SE: 6.7%) and the freedom from EL 2 was 89.0% (SE 6.4%) at 36 months. Cox regression analysis showed that the type of embolization (selective vs. non-selective), type of previous repair (f/bEVAR vs. EVAR), and use of anticoagulants did not affect follow-up outcomes. Reinterventions related to EL 2 were performed in 12.5%; three underwent an open conversion. Conclusions: TCE was related to high technical success and limited peri-operative morbidity, regardless of the type of initial endovascular aortic repair. Clinical success was encouraging with reinterventions for EL 2 affecting 12.5% of patients.

Impact of the Patency of Inferior Mesenteric Artery on 7-Year Outcomes After Endovascular Aneurysm Repair

PURPOSE

The impact of preoperative patent inferior mesenteric artery (IMA) on late outcomes following endovascular aneurysm repair (EVAR) remains unclear. This study aimed to investigate the specific influence of IMA patency on 7-year outcomes after EVAR.

MATERIALS AND METHODS

In this retrospective cohort study, 556 EVARs performed for true abdominal aortic aneurysm cases between January 2006 and December 2019 at our institution were reviewed. Endovascular aneurysm repairs performed using a commercially available device with no type I or type III endoleak (EL) during follow-up and with follow-up ≥12 months were included. A total of 336 patients were enrolled in this study. The cohort was divided into the patent IMA group and the occluded IMA group according to preoperative IMA status. The late outcomes, including aneurysm sac enlargement, reintervention, and mortality rates, were compared between both groups using propensity-score-matched data.

RESULTS

After propensity score matching, 86 patients were included in each group. The median follow-up period was 56 months (interquartile range: 32-94 months). The incidence of type II EL at discharge was 50% in the patent IMA group and 19% in the occluded IMA group (p<0.001). The type II EL from IMA and lumbar arteries was significantly higher in the patent IMA group than in the occluded IMA group (p<0.001 and p=0.002). The rate of freedom from aneurysm sac enlargement with type II EL was significantly higher in the occluded IMA group than in the patent IMA group (94% vs 69% at 7 years; p<0.001). The rate of freedom from reintervention was significantly higher in the occluded IMA group than in the patent IMA group (90% vs 74% at 7 years; p=0.007). Abdominal aortic aneurysm-related death and all-cause mortality did not significantly differ between groups (p=0.32 and p=0.34).

CONCLUSIONS

Inferior mesenteric artery patency could affect late reintervention and aneurysm sac enlargement but did not have a significant impact on mortality. Preoperative assessment and embolization of IMA might be an important factor for improvement in late EVAR outcomes.

CLINICAL IMPACT

The preoperative patency of the inferior mesenteric artery was significantly associated with a higher incidence of sac enlargement and reintervention with type II endoleak following endovascular aneurysm repair, even after adjustment for patient background. Preoperative assessment and embolization of inferior mesenteric artery might be an important factor for improvement in late EVAR outcomes.

Two-Stage Endovascular Aneurysm Repair with Preemptive Embolization: A Retrospective Study

BACKGROUND

Type II endoleak is the most common complication of endovascular aneurysm repair. Retrograde perfusion from the aneurysmal sac side branch to the aneurysmal sac, including the inferior mesenteric artery and lumbar arteries, is associated with adverse events after endovascular aneurysm repair, such as aneurysm sac enlargement, reintervention, rupture, and abdominal aortic aneurysm-related death. Preemptive embolization of the aneurysmal sac side branch before endovascular aneurysm repair is an effective and safe procedure for preventing type II endoleak and reducing the size of the aneurysmal sac. Since 2019, we have been conducting preemptive embolization of the inferior mesenteric artery and lumbar arteries. Thus, we intended to work on a two-stage endovascular aneurysm repair in which embolization and endovascular aneurysm repair are performed on separate days, owing to concerns about prolonged operative time and increased contrast media use and radiation exposure from performing endovascular aneurysm repair simultaneously. This study aimed to evaluate the effects of a two-stage endovascular aneurysm repair.

METHODS

This retrospective study included 114 cases of endovascular aneurysm repair (95 men and 19 women) for AAA performed at our hospital between January 2019 and December 2022. Inferior mesenteric artery and lumbar artery embolization were performed simultaneously with endovascular aneurysm repair (simultaneous group) in 49 cases, and two-stage embolization was performed (two-stage group) in 30 cases. The primary endpoints included the occurrence of T2EL during follow-up and the embolization rate of the IMA or LAs.

RESULTS

Type II endoleak did not occur in the two-stage group (follow-up period: 35 ± 6.2 months), whereas it was observed in 8.2% of patients more than 6 months after EVAR in the simultaneous group (follow-up period: 28 ± 5.5 months). While the total operative time was 340 ± 111.2 min in the simultaneous group, the durations for embolization and endovascular aneurysm repair in the two-stage group were 169 ± 35.5 min and 135.0 ± 26.4 min (total time 304 ± 31.2 min, P = 0.21), respectively, indicating a reduction in the total time required for the 2 techniques. The total amounts of contrast media used in the simultaneous and two-stage groups were 200.0 ± 179.2 mL and 182.0 ± 51.2 mL (P = 0.42), respectively, and the corresponding total radiation doses were 2502.4 ± 690.5 mGy and 2114.6 ± 351.2 mGy (P = 0.28), respectively, showing a decrease in both in the two-stage group. The lumbar artery embolization rates were 74.3% and 87.9% (P < 0.01) in the simultaneous and two-stage groups, respectively, indicating a significant difference.

CONCLUSIONS

Two-stage endovascular aneurysm repair with preemptive embolization of the inferior mesenteric artery and lumbar arteries may be an effective strategy for reducing type II endoleak occurrence, overall operative time, contrast use, and overall radiation exposure.

Midterm outcomes of side branch embolization and endovascular abdominal aortic aneurysm repair

OBJECTIVE

To analyze the effects of total side branch embolization at endovascular aneurysm repair (EVAR) for abdominal aortic aneurysms on the incidences of persistent type 2 endoleak (pT2EL), changes in sac diameter, and reintervention.

METHODS

Between 2013 and 2021, all patients who underwent primary EVAR with a few exceptions were included. Side branch embolization was considered during EVAR for inferior mesenteric artery (IMA) or IMA plus lumbar artery (LA) when feasible for contrast agent use. Outcomes measured were pT2EL, sac diameters, reintervention, ruptures, and aneurysm-related mortality. Radiation exposure and safety outcomes were also reported.

RESULTS

Among 732 patients who underwent EVAR, 616 (84.2%) were included. Of the 616 patients, 223 (36.2%) did not undergo side branch embolization (NO-E), whereas 228 (37.0%) underwent IMA only (IMA-E) and 165 (26.8%) underwent IMA+LA including median sacral artery (IMA+LA-E). The technical success rate of IMA and LA embolization was 97.0% and 74.7%, respectively. Crude incidences of pT2EL were significantly different from 6 months through 3 years (NO-E, 27.8%; IMA-E, 31.7%; IMA+LA-E, 9.4% at 3 years; P = .007). In the multivariate analysis adjusted for background differences, the incidences of pT2EL were significantly higher in the NO-E (odds ratio [OR], 3.21; 95% confidence intervals [CIs], 1.08-9.57; P = .004) and IMA-E (OR, 4.86; 95% CIs, 1.68-14.11; P = .004) compared with the IMA+LA-E group. Similarly, any reintervention until 3 years was significantly frequent in the NO-E (OR, 5.26; 95% CIs, 1.76-15.70; P = .003) and IMA-E group (OR, 4.19; 95% CIs, 1.38-12.67; P = .01). Surgical conversion and secondary rupture were seen only in 1 patient without any aneurysm-related mortality. Percent sac shrinkage from the baseline was significantly promoted in the IMA+LA group (NO-E, 12.1% ± 16.6%; IMA-E, 11.4% ± 16.7%; IMA+LA-E, 18.0% ± 18.8%; P = .047). Fluoroscopy time was significantly longer in the IMA+LA-E group (NO-E, 60.2 ± 47.4 minutes; IMA-E, 59.3 ± 39.5 minutes; IMA+LA-E, 75.5 ± 42.8 minutes; P < .0001), and so do the dose-area product (NO-E, 424.6 ± 333.4 Gy cm2; IMA-E, 477.7 ± 342.4 Gy cm2; IMA+LA-E, 631.8 ± 449.1 Gy cm2; P < .0001). No embolization-related complications or radiation-related adverse events were recorded.

CONCLUSIONS

Pre-emptive embolization of IMA, LAs, and median sacral artery at the time of EVAR reduced the incidences of pT2EL and any reintervention and promoted sac shrinkage during the follow-up period of 3 years.

Impact of the Lumbar Arteries on Aneurysm Diameter and Type 2 Endoleak after Endovascular Aneurysm Repair

BACKGROUND

Prophylactic embolization of the inferior mesenteric artery (IMA) during endovascular aneurysm repair (EVAR) is recommended to prevent type 2 endoleak (T2EL). However, the impact of patent lumbar arteries (LAs) on T2ELs and aneurysm diameter has not been elucidated.

METHODS

Fifty-seven consecutive patients who underwent EVAR at our institution between January 2013 and September 2022 and whose IMA had been occluded preoperatively or newly occluded postoperatively were included in the study. Predictive factors for aneurysm sac enlargement, sac shrinkage, and T2EL were investigated.

RESULTS

T2ELs occurred in 22.8% of the patients. The 4-year cumulative incidence rates of sac enlargement and shrinkage were 6.7% and 64.6%, respectively. The number of postoperative patent LAs was identified as a risk factor for T2ELs (95% confidence interval [CI]: 1.54-12.7, P = 0.0065). The number of postoperative patent LAs was found to be a significant predictor of sac enlargement (adjusted hazard ratio [AHR] 3.15, 95% CI: 1.43-6.96, P = 0.0045) and shrinkage (AHR 0.63, 95% CI: 0.43-0.91, P = 0.014).

CONCLUSIONS

The current study demonstrated that the number of postoperative patent LAs had a significant impact on the development of T2ELs and the change in aneurysm diameter in patients in whom the IMA was occluded after EVAR.

Impact of Patent Lumbar Arteries on Aneurysm Sac Enlargement with Type II Endoleak after Endovascular Aneurysm Repair

OBJECTIVE

This study aimed to investigate the impact of the number of patent lumbar arteries (LAs) on sac enlargement after endovascular aneurysm repair (EVAR).

METHODS

This was a retrospective cohort single centre registry study. Between January 2006 and December 2019, 336 EVARs were reviewed using a commercially available device excluding type I or type III endoleaks during a follow up of ≥ 12 months. Patients were divided into four groups based on the pre-operative patency of the inferior mesenteric artery (IMA) and high (≥ 4) or low (≤ 3) number of patent LAs: Group 1, patent IMA and high number of patent LAs; Group 2, patent IMA and low number of patent LAs; Group 3, occluded IMA and a high number of patent LAs; Group 4, occluded IMA and low number of patent LAs.

RESULTS

Groups 1, 2, 3, and 4 included 124, 104, 45, and 63 patients, respectively. The median follow up duration was 65.1 months. Significant differences in the incidence of overall type II endoleak (T2EL) at discharge between Group 1 and Group 2 (59.7% vs. 36.5%, p < .001) and between Group 3 and Group 4 (33.3% vs. 4.8%, p < .001) were observed. In patients with a pre-operatively patent IMA, the rate of freedom from aneurysm sac enlargement was significantly lower in Group 1 than in Group 2 (69.0% vs. 81.7% five years after EVAR, p < .001). In patients with a pre-operatively occluded IMA, the freedom rate from aneurysm sac enlargement was not significantly different between Groups 3 and Group 4 (95.0% vs. 100% five years after EVAR, p = .075).

CONCLUSION

A high number of patent LAs seemed to have a significant role in sac enlargement with T2EL when the IMA was patent pre-operatively, whereas a high number of patent LAs seemed to have limited influence on sac enlargement when the IMA was occluded pre-operatively.

Impact of patient demographics and intraoperative characteristics on abdominal aortic aneurysm sac following endovascular repair

BACKGROUND

Endovascular aortic repair (EVAR) has become the preferred treatment for abdominal aortic aneurysm (AAA). Its main aim is to seal the perfusion of the aneurysmal sac and, thus, induce sac regression and subsequent aortic remodelling. Aneurysmal sac regression has been linked to the short- and long-term clinical outcomes post-EVAR. It has also been shown to be influenced by endograft device choice, with several of these available commercially. This review summarises and discusses current evidence on the influence of pre- and intraoperative factors on sac regression. Additionally, this review aims to highlight the device-specific variations in sac regression to provide an overall holistic approach to treating AAAs with EVAR.

METHODS

A comprehensive literature search was conducted using multiple electronic databases to identify and extract relevant data.

RESULTS

Female sex, >70 mm original sac diameters, higher pre-procedural fibrinogen levels, smoking and low intra-aneurysmal pressure were found to positively impact sac regression. Whereas renal impairment, ischemic heart disease, high intra-aneurysmal pressure and aneurysm neck thrombus negatively influenced sac regression. Patent lumbar arteries, age, statins and hypercholesterolaemia displayed conflicting evidence regarding sac regression. Regarding the EVAR endografts compared, newer generation devices such as the Anaconda mainly showed the most optimal results.

CONCLUSION

Sac regression following EVAR in AAA is an important prognostic factor for morbidity and mortality. Nevertheless, several pre- and intraoperative factors can have an influence on sac regression. Therefore, it is necessary to take them into account when assessing AAA patients for EVAR to optimise outcomes. The choice of EVAR stent-graft can also affect sac regression, with evidence suggesting that the Fenestrated Anaconda is associated with the most favourable results.

Patent iliolumbar artery increase no risk of type II endoleaks after endovascular abdominal aortic aneurysm: a case-control study

Objective

The aims of the present study were to explore the risk factors for type 2 endoleaks (T2ELs) after endovascular aneurysm repair (EVAR) and the association between T2ELs and the iliolumbar artery.

Materials and methods

A single-center, retrospective case-control study in West China Hospital was conducted among patients with infrarenal abdominal aortic aneurysm (AAA) who underwent EVAR between June 2010 and June 2019. The associations of patient characteristics, anatomical factors, internal iliac artery embolization, and ILA with the primary outcome were analyzed. The secondary objective was to analyze survival and reintervention between the T2EL group and the non-T2EL group. Kaplan-Meier survival, propensity matching analysis and multivariate logistic regression analysis were used.

Results

A total of 603 patients were included. The median follow-up was 51 months (range 5.0-106.0). There was a significant difference in the diameter of the lumbar artery (LA), middle sacral artery (MSA) and inferior mesentery artery (IMA), proportion of thrombus and LA numbers. The univariate analysis showed that T2ELs were more likely to develop more thrombus in aneurysm cavity (OR = 0.294, p = 0.012), larger MSA (OR = 1.284, p = 0.04), LA (OR = 1.520, p = 0.015), IMA (OR = 1.056, p < 0.001) and more LAs (OR = 1.390, p = 0.019). The multivariate analysis showed that the number of LAs (HR: 1.349, 95% CI: 1.140-1.595, p < .001) and the diameter of the IMA (HR: 1.328, 95% CI: 1.078-1.636, p = 0.008) were significantly associated with T2ELs. There were no new findings from the propensity score matching. The reintervention-free survival rates were significantly different between the two groups (p = 0.048). Overall survival and AAA-related death rates were not different between the two group. This was consistent with the PSM analysis.

Conclusion

The iliolumbar artery and the different internal iliac artery interventions may not increase the incidence of T2ELs. But the numbers of LAs and IMA diameter were independent risk factors for T2Els. T2ELs was associated with the reintervention but did not affect long-term survival or increase aneurysm-related mortality after EVAR.

A nomogram risk assessment model to predict the possibility of type II endoleak-related re-intervention after endovascular aneurysm repair (EVAR)

This study aimed to develop and validate a novel nomogram risk assessment model to predict the possibility of type II endoleak (T2EL)-related re-intervention. The data of 455 patients with abdominal aortic aneurysms who underwent elective endovascular aneurysm repair (EVAR) procedures between January 2018 and December 2021 at our single center were retrospectively reviewed. Following the implementation of exclusion criteria, 283 patients were finally included and divided into T2EL-related re-intervention (n = 42) and non-T2EL (n = 241) groups. The overall T2EL-related re-intervention rate for 283 patients was 14.8% (42/283). Using multivariate analysis, significant risk factors for re-intervention included age (OR, 1.172; 95% CI, 1.051-1.307; P = 0.004), smoking (OR, 13.418; 95% CI, 2.362-76.215; P = 0.003), diameter of inferior mesenteric artery (IMA) (OR, 21.380; 95% CI, 3.060-149.390; P = 0.002), and number of patent lumbar arteries (OR, 9.736; 95% CI, 3.175-29.857; P < 0.001). The discrimination ability of this risk-predictive model was reasonable (concordance index [C-index] = 0.921; 95% CI, 0.878-0.964). The Hosmer-Lemeshow goodness of fit test was performed on the model, and the chi-square value was 3.210 (P = 0.920), presenting an excellent agreement between the model-predicted and observed values. The receiver operating characteristic (ROC) curve identified that the risk thresholds of re-intervention were a diameter of > 2.77 mm for the diameter of the inferior mesenteric artery and a proportion of < 45.5% for thrombus volume in the aneurysm sac. This novel nomogram risk assessment model for predicting the possibility of patients' T2EL-related re-interventions after EVAR should be helpful in discriminating high-risk patients. Two novel risk thresholds may imply a higher possibility of T2EL-related re-intervention after EVAR.

One-year sac regression is associated with freedom from fatal adverse events after endovascular aneurysm repair

OBJECTIVE

Although the predictors of long-term prognosis after endovascular aneurysm repair (EVAR) have been investigated, several reports have suggested that early sac shrinkage (ESS) is associated with superior long-term prognosis. However, it was not clear whether ESS was associated with aneurysm-related mortality. The aim of this study was to define fatal adverse events and to examine their association with ESS.

METHODS

All consecutive patients who underwent EVAR for an abdominal aortic aneurysm at Nagoya University Hospital between June 2007 and August 2018 were identified. We defined ESS as an aneurysm diameter decrease of 10 mm or more at 1 year after EVAR, and we defined fatal adverse events as aneurysm-related death, aneurysm sac rupture, open conversion, secondary type Ia endoleak, or secondary type IIIa/b endoleak. Then, we evaluated the association between ESS and fatal adverse events and identified predictors of ESS.

RESULTS

During the study period, 553 patients were identified and included. Fatal adverse events occurred in 42 patients (7.6%), and the details of the fatal adverse events were as follows: 13 aneurysm-related deaths, 17 aneurysm sac ruptures, 14 open conversions, 13 type Ia endoleaks, and 6 type III endoleaks. ESS occurred in 146 patients (26.4%). Kaplan-Meier curves showed that the ESS group had a significantly lower incidence of fatal adverse events (P < .001). Multivariate analysis showed that there were significant differences in terms of 5 or more preoperatively patent lumbar arteries (odds ratio [OR], 0.67; P = .049; 95% confidence interval [CI], 0.45-1.00), chronic kidney disease (OR, 0.49; P < .01; 95% CI, 0.29-0.84), and Zenith endograft use (OR, 1.76; P < .01; 95% CI, 1.16-2.67). Furthermore, the percentage of cases that achieved an aneurysm diameter of less than 40 mm was significantly higher in the ESS group (76.0% vs 15.5%; P < .01). The use of Zenith endografts showed a significantly higher rate of aneurysm disappearance than the use of Endurant endografts (P < .01) and Excluder endografts (P < .01). In addition, it was found that ESS was more likely to occur with the use of Zenith endografts, even when propensity score matching was performed for the neck morphology.

CONCLUSIONS

ESS was associated with a lower rate of life-threatening adverse events after EVAR. The use of Zenith endografts was a predictor of ESS and was associated with increased rates of long-term sac shrinkage and aneurysm disappearance compared with the Endurant and Excluder endografts. Using the predictors of ESS identified in this study, we may be able to expand the indications for EVAR to patients with a longer life expectancy.

Incidence and Fate of Refractory Type II Endoleak after EVAR: A Retrospective Experience of Two High-Volume Italian Centers

Introduction: The aim of the present study is to report the outcome of patients presenting an isolated type II endoleak (TIIEL) requiring reintervention and to identify clinical and anatomical characteristics potentially implicated in refractory TIIEL occurrence and fate. Materials and Methods: A multicenter retrospective study on TIIEL requiring reintervention was conducted between January 2003 and December 2020. Demographic and clinical characteristics, procedural technical aspects, reinterventions, and outcomes were recorded. TIIEL determining sac expansion greater than 10 mm underwent a further endovascular procedure aiming to exclude aneurismal sac. Redo endovascular procedures were performed via endoleak nidus direct embolization and/or aortic side branches occlusion. TIIELs responsible for persisting aneurysmal sac perfusion 6 months after redo endovascular procedures were classified as “refractory” and submitted to open conversion. Results: A total of 102 TIIEL requiring reintervention were included in the final analysis. Eighty-eight (86.27%) patients were male, the mean age was 77.32 ± 8.08 years, and in 72.55% of cases the American Society of Anaesthesiologists (ASA) class was ≥3. The mean aortic diameter was 64.7 ± 14.02 mm, half of treated patients had a patent inferior mesenteric artery (IMA), and 44.11% ≥ 3 couples of patent lumbar arteries (LA). In 49 cases (48.03%) standard endovascular aneurysm repair (EVAR) procedure was completed without adjunctive maneuvers. All enrolled patients were initially submitted to a further endovascular procedure once TIIEL requiring reintervention was diagnosed; 57 patients underwent LAs or IMA embolization (55.87%), 42 transarterial aneurismal sac embolization (41.17%), and three (2.96%) laparoscopic ostial ligations of the inferior mesenteric artery. During a mean follow-up of 15.22 ± 7.57 months (7−48), a redo endovascular approach was able to ensure complete sac exclusion in 52 cases, while 50 patients presented a still evident refractory TIIEL and therefore a surgical conversion or semiconversion was conducted. At the univariate analysis refractory TIIEL patients were significantly different from those who did not develop the complication in terms of preoperative clinical, morphological characteristics, and initial EVAR procedures: coronary artery disease occurrence (p = 0.005, OR: 3.18, CI95%: 1.3−7.2); preoperative abdominal aortic aneurysm (AAA) sac diameter (p = 0.0055); IMA patency (p = 0.016, OR: 2.64, CI95%: 1.18−5.90); three or more patent LAs; isolated standard EVAR without adjunctive procedures (p > 0.0001; OR: 9.48, CI95%: 3.84−23.4). Conclusions: Our experience seems to demonstrate that it is reasonable to try to preoperatively identify those patients who will develop a refractory TIIEL after EVAR and those with a TIIEL requiring reintervention for whom a simple endovascular redo will not be enough, needing surgical conversion.