Efficacy of Sac Coil Embolization in Endovascular Aortic Repair for Sac Shrinkage in Patients at a High Risk of Type II Endoleak from Lumbar Arteries.

BACKGROUND: In endovascular aortic repair (EVAR), preemptive embolization of sac branch vessels is effective in preventing postoperative type II endoleak (T2EL). However, this technique has not been widely adopted especially for lumbar arteries (LAs) because of technical difficulties and time constraints. This study aimed to investigate the efficacy of nonselective sac coil embolization, which is a simpler surgical method, in postoperative sac shrinkage for patients at a high risk of T2EL from LAs. METHODS: We retrospectively assessed 76 patients who underwent elective EVAR for abdominal aortic aneurysm with 4 or more patent LAs or at least 1 patent LA of ≥2 mm at our hospital between January 2014 and December 2022. The patients who underwent sac coil embolization were included in Group Ⅰ (n = 20), and the others were divided into 2 groups: those with an inferior mesenteric artery that was originally occluded or embolized by coils or stent graft bodies (Group Ⅱ, n = 21), and those without that (Group Ⅲ, n = 35). In Group Ⅰ, 0.035-inch coils were inserted into the sac after complete stent graft deployment. The cumulative incidence of sac shrinkage (≥5 mm) was compared between the groups. Further, univariable and multivariable Cox regression analyses were used to determine the predictors of sac shrinkage. RESULTS: Sac shrinkage (≥5 mm) was observed more frequently in Group Ⅰ (50%) than in Group Ⅱ (19%) and Group Ⅲ (17%) (P = 0.052 and 0.043, respectively). The cumulative incidence of sac shrinkage was significantly higher in Group Ⅰ than in Group Ⅱ (log-rank P = 0.039) and Group Ⅲ (log-rank P = 0.024). Multivariable Cox regression analyses revealed that sac embolization was a significant predictor of sac shrinkage (hazard ratio, 4.23; 95% confidence interval, 1.66-10.8; P = 0.003). CONCLUSIONS: Nonselective sac coil embolization in EVAR is potentially effective for sac shrinkage in the early postoperative phase in patients at high risk of T2EL from LAs. This simple procedure may improve prognosis after EVAR.

CIRSE Standards of Practice on Management of Endoleaks Following Endovascular Aneurysm Repair.

BACKGROUND: Endoleaks represent the most common complication after EVAR. Some types are associated with ongoing risk of aneurysm rupture and necessitate long-term surveillance and secondary interventions. PURPOSE: This document, as with all CIRSE Standards of Practice documents, will recommend a reasonable approach to best practices of managing endoleaks. This will include imaging diagnosis, surveillance, indications for intervention, endovascular treatments and their outcomes. Our purpose is to provide recommendations based on up-to-date evidence, updating the guidelines previously published on this topic in 2013. METHODS: The writing group was established by the CIRSE Standards of Practice Committee and consisted of clinicians with internationally recognised expertise in endoleak management. The writing group reviewed the existing literature performing a pragmatic evidence search using PubMed to select publications in English and relating to human subjects up to 2023. The final recommendations were formulated through consensus. RESULTS: Endoleaks may compromise durability of the aortic repair, and long-term imaging surveillance is necessary for early detection and correct classification to guide potential re-intervention. The majority of endoleaks that require treatment can be managed using endovascular techniques. This Standards of Practice document provides up-to-date recommendations for the safe management of endoleaks.

Injection of n-Butyl-2-Cyanoacrylate into the Abdominal Aortic Aneurysm Sac during Endovascular Aortic Repair to Prevent Type II Endoleaks Caused by Lumbar Arteries.

PURPOSE: To evaluate midterm results of whether the strategy to occlude target lumbar arteries using n-butyl-2-cyanoacrylate (nBCA) injection during endovascular aneurysm repair (EVAR) reduced the incidence of Type II endoleak (T2EL) after EVAR. MATERIALS AND METHODS: Between 2013 and 2020, 187 patients underwent EVAR; 106 in the treatment group received nBCA injection during EVAR, whereas 81 in the historical control group did not. The incidence of T2EL at 7 days, need for reintervention, and post-EVAR aneurysmal shrinkage were compared between the groups. RESULTS: Between the treatment group and the control group, significant differences were achieved in the incidence of T2EL (2.8% vs 28.4%; P < .0001) and decreased aneurysmal diameter was observed at 1 year after EVAR (-5.2 vs -3.8 mm; P = .034). In multivariate analysis, nBCA injection (odds ratio [OR], 0.04; P = .001) and younger age (OR, 0.92; P = .036) were significantly associated with a reduced incidence of T2EL. As a possible adverse event associated with nBCA injection, 2 cases of transient lower-limb motor dysfunction (1.9%) were observed. Propensity score analysis revealed that the treatment group had a significantly lower incidence of T2EL than that in the control group (P = .0002) even though there was no difference in the incidence of inferior mesenteric artery coil embolization between the groups. The survival rate without aneurysm sac enlargement (100.0% vs 69.8%; P = .014) and the reintervention-free rate (100.0% vs 63.1%; P = .034) in the treatment group were significantly higher than those in the control group. CONCLUSIONS: Concomitant nBCA injection can provide durable EVAR without T2EL, as supported by the avoidance of reintervention associated with aneurysm sac enlargement.

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.

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.

Fate of primary determinate and indeterminate target vessel endoleaks after fenestrated-branched endovascular aortic repair.

OBJECTIVE: The aim of this study was to investigate the outcomes of primary determinate and indeterminate target vessel endoleaks (TVELs) after fenestrated-branched endovascular aortic repair (F-BEVAR). METHODS: We conducted a single-center retrospective study (2014-2023) on F-BEVAR for thoracoabdominal (TAAAs) or pararenal aortic aneurysms (PRAAs). TVELs were classified as "primary" if present at the first postoperative computed tomography angiogram. Endoleaks were defined "determinate" (dELs) if the cause (type Ic or IIIc) and implicated target vessel were identifiable and "indeterminate" (iELs) if contrast enhancement was detectable at the level of fenestrations/branches without any evident source. Endoleaks involving multiple inflows (type II and target vessels) were defined as "complex" (cELs). Endpoints were endoleak spontaneous resolution, 1-year aneurysm sac failure to regress (>5 mm diameter decrease), and 4-year endoleak-related secondary interventions. Kaplan-Meier estimates and Cox regression were used for the analysis. RESULTS: There were 142 patients with JRAAs/PRAAs (n = 85; 60%) or TAAAs (n = 57; 40%), with 513 target arteries incorporated through a fenestration (n = 294; 57%) or directional branch (n = 219; 43%). Fifty-nine primary TVELs (12%) were identified in 35 patients (25%), a dEL in 20 patients (14%) and iEL in 15 (11%); 22 (15%) had a determinate or indeterminate cEL. Overall spontaneous resolution rate was 75% (95% confidence interval [CI], 51%-87%) at 4 years. cELs (odds ratio [OR], 5.00; 95% CI, 1.10-49.4; P < .001) and iELs after BEVAR (OR, 9.43; 95% CI, 3.41-56.4; P = .002) were more likely to persist >6 months, and persistent forms were associated with sac failure to regress at 1 year (OR, 1.72; 95% CI, 1.03-12.59; P = .040). Overall freedom from endoleak-related reinterventions was 85% (95% CI, 79%-92%) at 4 years, 92% (95% CI, 87%-97%) for those without primary TVELs and 62% (95% CI, 46%-84%) for those with any primary TVEL (P < .001). In particular, cELs (hazard ratio, 1.94; 95% CI, 1.4-18.81; P = .020) were associated with an increased need for reintervention. In case a secondary intervention was needed, iEL or cEL had an increased risk for multiple secondary procedures (hazard ratio, 2.67; 95% CI, 1.22-10.34; P = .034). CONCLUSIONS: Primary TVELs are frequent after F-BEVAR, and a clear characterization of the endoleak source by computed tomography angiogram is not possible in 40% of patients. Most primary TVELs spontaneously resolve, but during follow-up, patients with any primary TVEL experience a worsened freedom from endoleak-related reinterventions that is mostly driven by persistence of cELs and post-BEVAR iELs. Multiple secondary procedures may be required in case of iELs or cELs.

Is There a Role for Heli-FX Endoanchors in Treating Type 1B Common Iliac Artery Endoleaks?

OBJECTIVES: The management of type 1B endoleaks following endovascular aortic aneurysm repair (EVAR) can be challenging. The Heli-FX Endoanchor system effectively treats proximal type 1A endoleaks but has not been used for type 1B common iliac artery endoleaks. This study demonstrates that it is both safe and effective in being used in the common iliac artery (CIA) limb of an EVAR. METHODS: A retrospective review of patients identified through coding and medical records was performed to extract information on demographics, aneurysmal features, operative features, and postoperative outcomes. This was then collated and analysed thoroughly and compared to existing research. RESULTS: Four patients with six type 1B CIA endoleaks were treated with Heli-FX Endoanchors in the CIA limbs of EVAR grafts. There was 100% technical success rate with complete exclusion of the endoleaks at 6 months. With mean follow up of 714 days, there were no Endoanchor-specific complications. One patient required explantation of the aortic endograft due to contralateral limb fracture, where it was found that an Endoanchor had penetrated the common iliac vein, requiring primary closure. CONCLUSIONS: Heli-FX Endoanchors were effective within this cohort of patients, though key risks were identified. Adjacent anatomy to the CIA must be considered, which also have nearly half the arterial thickness compared to the aorta. Pre-operative planning is essential given the theoretical risk of placing Endoanchors.

Reducing aneurysm sac growth and secondary interventions following endovascular abdominal aortic aneurysm repair by preemptive coil embolization of the inferior mesenteric artery and lumbar arteries.

OBJECTIVE: Type II endoleak (EL-2) is the most common complication following endovascular aneurysm repair (EVAR), leading to continued sac growth and potential rupture. In this study, we examined the association between patency of the inferior mesenteric artery (IMA) and lumbar arteries (LAs) with respect to sac growth. The effect of preemptive embolization of the IMA and/or LAs on the need for secondary interventions for sac growth post-EVAR was also evaluated. METHODS: A retrospective cohort study was performed on consecutive patients who underwent EVAR for non-ruptured, infrarenal abdominal aortic aneurysms (AAAs) from January 2012 to December 2020. A select group of patients underwent preemptive embolization of the IMA and/or LA. Patients with any types I, III, or IV endoleaks were excluded. Patency of the IMA and LA on preoperative computed tomography angiogram (CTA) was evaluated on TeraRecon workstation. All secondary interventions to treat EL-2 were recorded. Sac growth was defined as centerline axial diameter increase of ≥5 mm on follow-up CTA. RESULTS: A total of 300 patients (mean age, 74 ± 8.5 years; 83.7% male) underwent EVAR. Ninety-nine patients had preemptive embolization of the IMA and/or LA. Mean follow-up of the cohort was 59.3 ± 30.5 months. Thirty-six patients (12%) demonstrated sac growth on follow-up; 12 of these (33.3%) had preemptive embolization. The median time until detection of sac growth was 28.8 months (interquartile range, 15.2-46.5 months), with a mean growth of 10.1 ± 6.4 mm. Sac growth was significantly associated with presence of EL-2: 27 of 36 (75%) with EL-2 vs 9 of 36 (25%) without EL-2 (P < .001). Patients with sac growth had a higher mean total number (2.6 ± 1.5) of patent lower LAs (L3, L4) compared with those without (2.0 ± 1.4; P = .03). Patency of L1, L2, and L3 LAs were not associated with sac growth. However, patency of at least one L4 LA was significantly associated with sac growth (14.8% vs 7.7%; P = .04). The highest incidence of sac growth (17.6%) was seen when both IMA and L4 LA were patent; significantly different from the lowest incidence (5.3%) when both were occluded preoperatively (P = .018). Preemptive coiling of the IMA and/or LA significantly reduced the need for post-EVAR secondary intervention for sac growth. Freedom from post-EVAR secondary intervention was achieved in 92 of 99 (92.9%) pre-EVAR coiled patients vs 163 of 201 (81.5%) patients who did not undergo pre-EVAR coiling (P = .009). CONCLUSIONS: Preemptive coil embolization of the IMA and LAs, especially L4 LA, reduces the need for secondary interventions for sac growth, potentially improving the long-term durability of EVAR.

Effectiveness of Intra-operative Contrast-Enhanced Ultrasound Assessment to Optimize Type II Endoleak Embolization.

PURPOSE: To analyze the effectiveness of type II endoleaks (T2E) embolization using intra-operative contrast-enhanced ultrasound (CEUS). METHODS: Consecutive patients treated for T2E underwent a standardized protocol with trans-arterial or trans-lumbar access, large volume embolization, onlay fusion, and intra-operative CEUS. Technical success was defined by exclusion of endoleak by CEUS. RESULTS: Twenty-six patients (mean age 81 ± 11 years old; 89% male) were treated. The mean aneurysm sac enlargement was 11 ± 8 mm from T2E diagnosis. Embolization was performed using Onyx® 18 in all patients with adjunctive coils in 13 patients (50%). After the first embolization, CEUS documented residual T2E in 13 patients (50%). Ten patients (38%) had additional embolization, which successfully eradicated the T2E in seven of them. Technical success was 50% after the first embolization attempt and 77% after additional attempts guided by CEUS (P = 0.080). There was no mortality. Median imaging follow-up was 22 months. Among the 20 patients with no residual T2E on completion CEUS, 16 (80%) had sac stabilization and none required additional interventions for T2E. Of the six patients with residual T2Es on CEUS, three had sac stabilization (50%) and one required additional reintervention for T2E. There was one late aortic rupture at 56 months. CONCLUSION: One in two patients treated by T2E embolization had residual endoleak on intra-operative CEUS after a first embolization attempt, decreasing to one in four patients after multiple attempts. A negative completion CEUS following embolization was associated with higher rates of sac stabilization and no need for additional T2E embolization.

Endoleak in covered CP stent causes procedural failure during transcatheter closure of sinus venosus defects.

Transcatheter sinus venosus defect closure uses a long covered stent of appropriate length and diameter across the cavoatrial junction after balloon interrogation. The fabric in the covered stent creates a roof for the right upper pulmonary vein that closes the interatrial communication and redirects the vein into the left atrium behind the stent. A fabric tear in the covered stent may cause endoleak that will result in residual flows across the struts of the covered stent, causing procedural failure. This report highlights the identification of fabric leak by angiography and transesophageal echocardiography and steps to overcome this complication by the placement of another overlapping covered stent.

Management of Endoleaks After Elective Infrarenal Aortic Endovascular Aneurysm Repair: A Review.

Importance: Endovascular aneurysm repair (EVAR) is the dominant treatment strategy for abdominal aortic aneurysms, encompassing 80% of all repairs in the United States. Endoleaks are ubiquitous and affect 30% of patients treated by EVAR, potentially leading to sac enlargement and increased risk of rupture. The care of EVAR patients requires long-term surveillance by a multidisciplinary team. Accordingly, physicians should be familiar with the fundamentals of endoleak management to achieve optimal outcomes, including timely referral for remediation or providing counseling and reassurance when needed. Observations: PubMed and the Cochrane database were searched for articles published between January 2002 and December 2022 in English, addressing epidemiology, diagnosis, and management of endoleaks after EVAR. Endoleaks can be detected intraoperatively or years later, making lifelong surveillance mandatory. Type I and III have the highest risk of rupture (7.5% at 2 years and 8.9% at 1 year, respectively) and should be treated when identified. Intervention should be considered for other types of endoleak when associated with aneurysm sac growth larger than 5 mm based on current guidelines. Type II endoleaks are the most common, accounting for 50% of all endoleaks. Up to 90% of type II endoleaks resolve spontaneously or are not associated with sac enlargement, requiring only observation. Although the risk of rupture is less than 1%, cases that require reintervention are challenging. Recurrence is common despite endovascular treatment, and rupture can occur without evidence of sac growth. Type IV endoleaks and endotension are uncommon, are typically benign, and primarily should be observed. Conclusions and Relevance: Endoleak management depends on the type and presence of sac expansion. Type I and III endoleaks require intervention. Type II endoleaks should be observed and treated selectively in patients with significant sac expansion. Since endoleaks can appear any time after EVAR, at least 1 contrast-enhanced computed tomographic angiogram or duplex ultrasound by an experienced laboratory is recommended every 5 years.

Use of the Endoleak-to-Aortic Density Ratio to Distinguish Direct Endoleaks from Indirect Endoleaks after Endovascular Aortic Aneurysm Repair.

PURPOSE: To define criteria to distinguish direct (type 1 or 3) from indirect endoleaks (type 2) in the arterial phase of contrast-enhanced computed tomography (CT) scans in patients with abdominal aortic aneurysms treated with endovascular aortic repair. MATERIALS AND METHODS: This retrospective study was conducted from January 2009 to October 2020 and included consecutive patients treated endovascularly for a direct endoleak or an indirect endoleak associated with an enlarging aneurysm. The following characteristics were evaluated using contrast-enhanced CT: location, size, contact with the endograft, density, morphologic criteria, collateral artery enhancement, and endoleak-to-aortic density ratio. Statistical analysis included the Mann-Whitney U test, Pearson χ2 test, Fisher exact test, receiver operating characteristic curve analysis, and multivariable logistic regression. RESULTS: Contrast-enhanced CT scans from 71 patients (87% men), who presented with 87 endoleaks (44 indirect and 43 direct endoleaks), treated by endovascular techniques were analyzed. Using visual criteria, 56% of the endoleaks were not characterizable as direct or indirect. An endoleak-to-aortic density ratio of >0.77 could properly distinguish direct from indirect endoleaks, with a theoretical accuracy of 98% (area under the receiver operating characteristic curve, 0.99), sensitivity of 95%, specificity of 100%, positive predictive value of 100%, and negative predictive value of 96%. CONCLUSION: An endoleak-to-aortic density ratio of >0.77 in the arterial phase of contrast-enhanced CT could be a strong discriminant of a direct-type endoleak.

Feasibility of aortic aneurysm sac embolization using a novel shape memory polymer embolic device.

BACKGROUND: We investigated the feasibility of aneurysm sac embolization using a novel self-expanding porous shape memory polymer (SMP) device during endovascular aortic abdominal or thoracic aneurysm repair (EVAR). METHODS: Retrospective analysis of consecutive patients treated at 2 centers in Germany. Patients were treated from January 2019 to July 2021 with follow-up at 7 days and 3, 6, and 12 months. Aneurysm sacs were implanted with SMP devices immediately following endograft placement during the same procedure. Primary endpoint was technically successful SMP-device deployment into the aneurysm sac outside the endograft. Secondary endpoints were changes in aneurysm volume and associated complications (e.g., endoleaks). RESULTS: We included 18 patients (16 males), aged 72 ± 9 years, achieving 100% technical success. Mean preprocedure aortic aneurysm sac volume was 195 ± 117 mL with a perfused aneurysm volume of 97 ± 60 mL. A mean of 24 ± 12 SMP devices per patient were used (range 5-45, corresponding to 6.25-56.25 mL expanded embolic material volume). All evaluable patients exhibited sac regression except 2 patients yet to reach 3-month follow-up. At mean 11 ± 7 months (range 3-24), change in aneurysm volume from baseline was -30 ± 21 mL (p < 0.001). In 8 patients, aneurysm regression was observed despite type 2 endoleaks in 6 and type 1A endoleaks in 2, none of them requiring further intervention to date. No morbidity or mortality related to this treatment occurred. CONCLUSIONS: SMP devices for aortic aneurysm sac embolization during endovascular repair appear feasible and safe in this small case series. Prospective studies are needed. KEY POINTS: • Shape memory polymer is a novel, self-expanding, porous, and radiolucent embolic device material. • Aortic aneurysm sacs were treated with polymer devices immediately following endograft placement. • Aortic aneurysm sac regression was observed in all patients with over 3-month follow-up. • Aortic aneurysm sac regression was observed even in the presence of endoleaks.

Five-year results of the LEOPARD trial of commercially available endografts.

OBJECTIVE: The LEOPARD (Looking at EVAR Outcomes by Primary Analysis of Randomized Data) trial is a randomized controlled trial comparing the outcomes of endovascular aneurysm repair (EVAR) using commercially available devices in a real-world population. METHODS: A prospective, randomized, multi-center trial was performed to compare the anatomically fixated (AF) AFX/AFX2 endograft system (Endologix) with endografts with proximal fixation (PF) (Cook Medical Zenith Flex; Gore Excluder; and Medtronic Endurant II) in patients with infrarenal abdominal aortic aneurysms. The primary endpoint was freedom from aneurysm-related complications (ARCs), a composite endpoint consisting of perioperative death (≤30 days), aneurysm rupture, conversion to open surgical repair, postoperative endoleaks, endograft migration (≥10 mm), aneurysm enlargement (≥5 mm), endograft limb occlusion, and device- or aneurysm-related reintervention. RESULTS: The study population was 455 patients enrolled at 56 United States centers: 235 patients were treated with AF devices and 220 with PF devices. The primary endpoint supported noninferiority of the AF cohort at 1 year. The 5-year freedom from ARC Kaplan-Meier estimates were 63.8% for AF patients and 55.5% for PF patients (P = .10). Kaplan-Meier estimates for freedom from aneurysm-related mortality were 98.7% and 97.0% in the AF group and 99.5% and 98.5% in the PF group at 1 and 5 years. There was no difference in aneurysm-related mortality, all-cause mortality, rupture, secondary interventions, and type I and type III endoleak between the two cohorts. The type III endoleak rate at 5 years for the AFX cohort was 1.5% and 0.0% for the comparator cohort (P = .11). There was a lower type II endoleak rate in the AF group at 5 years (78.8% vs 68.4%; P = .037). There were zero open surgical conversions (0.0%) in the AF group and four (2.0%) in the PF group. CONCLUSIONS: The 5-year results from the LEOPARD study demonstrated that there was no clinically significant difference in overall aneurysm-related outcomes between patients randomized to the AFX endograft system or commercially available endografts with proximal fixation.

High incidence of type 2 endoleak and low associated adverse events in the Vascular Quality Initiative linked to Medicare claims.

INTRODUCTION: Type 2 endoleak (T2EL) is the most common adverse finding on postoperative surveillance after endovascular aortic aneurysm repair (EVAR). A low rate of aneurysm-related mortality with T2EL has been established. However, the optimal management strategy and the efficacy of reintervention remain controversial. This study used data from the Vascular Quality Initiative linked to Medicare claims (VQI-Medicare) to evaluate T2LE in a real-world cohort. METHODS: This retrospective review of EVAR procedures in VQI-Medicare included patients undergoing their first EVAR procedure between 2015 and 2017. Patients with an endoleak other than T2EL on completion angiogram and those without VQI imaging follow-up were excluded. Patients without Medicare part A or part B enrollment at the time of the procedure or without 1-year complete Medicare follow-up data were also excluded. The exposure variable was T2EL, defined as any branch vessel flow detected within the first postoperative year. Outcomes of interest were mortality, reintervention, T2EL-related reintervention, post-EVAR imaging, and T2EL behavior including spontaneous resolution, aneurysm sac regression, and resolution after reintervention. The association of prophylactic branch vessel embolization (PBE) with T2EL resolution and aneurysm sac regression was also evaluated. RESULTS: In a final cohort of 5534 patients, 1372 (24.7%) had an identified T2EL and 4162 (75.2%) did not. The median age of patients with and without T2EL was 77 and 75 years, respectively. There were no differences in mortality, imaging, reintervention, or T2EL-related reintervention at 3 years after the procedure for patients with T2EL. The aneurysm sac diameter decreased by 4 mm (range: 9-0 mm decrease) in the total cohort. Patients with inferior mesenteric artery-based T2EL had the smallest decrease in aneurysm diameter (median 1 mm decrease compared with 1.5 mm for accessory renal artery-based T2EL, 2 mm for multiple feeding vessel-based T2EL, and 4 mm for lumbar artery-based T2EL; P < .001). Spontaneous resolution occurred in 73.7% of patients (n = 809). T2ELs with evidence of multiple feeding vessels were associated with the lowest rate of spontaneous resolution (n = 51, 54.9%), compared with those with a single identified feeding vessel of inferior mesenteric artery (n = 99, 60.0%), lumbar artery (n = 655, 77.7%), or accessory renal artery (n = 31, 79.5%) (P < .001). PBE was performed in 84 patients. Patients who underwent PBE and were without detectable T2EL after EVAR had the greatest rate of sac regression at follow-up (7 mm decrease) compared with baseline. CONCLUSIONS: T2EL after EVAR is associated with high rates of spontaneous resolution, low rates of aneurysm sac growth, and no evidence of increased early mortality or reintervention. PBE in conjunction with EVAR may be indicated in some circumstances.

Characterization and management of type II and complex endoleaks after fenestrated/branched endovascular aneurysm repair.

INTRODUCTION: Endoleaks are more common after fenestrated/branched endovascular aneurysm repair (F/B-EVAR) than infrarenal EVAR secondary to the length of aortic coverage and number of component junctions. Although reports have focused on type I and III endoleaks, less is known regarding type II endoleaks after F/B-EVAR. We hypothesized that type II endoleaks would be common and often complex (associated with additional endoleak types), given the potential for multiple inflow and outflow sources. We sought to describe the incidence and complexity of type II endoleaks after F/B-EVAR. METHODS: F/B-EVAR data prospectively collected at a single institution in an investigational device exemption clinical trial (G130210) were retrospectively analyzed (2014-2021). Endoleaks were characterized by type, time to detection, and management. Primary endoleaks were defined as those present on completion imaging or at first postoperative imaging, and secondary were those on subsequent imaging. Recurrent endoleaks were those that developed after a successfully resolved endoleak. Reinterventions were considered for type I or III endoleaks or any endoleak associated with sac growth >5 mm. Technical success defined as the absence of flow in the aneurysm sac at procedure conclusion and methods of intervention were captured. RESULTS: Among 335 consecutive F/B-EVARs (mean ± standard deviation follow-up: 2.5 ± 1.5 years), 125 patients (37%) experienced 166 endoleaks (81 primary, 72 secondary, and 13 recurrent). Of these 125 patients, 50 (40% of patients) underwent 71 interventions for 60 endoleaks. Type II endoleaks were the most frequent (n = 100, 60%), with 20 identified during the index procedure, 12 (60%) of which resolved before 30-day follow-up. Of the 100 type II endoleaks, 20 (20%; 12 primary, 5 secondary, and 3 recurrent) were associated with sac growth; 15 (75%) of those with associated sac growth underwent intervention. At intervention, 6 (40%) were reclassified as complex, with a concomitant type I or type III endoleak. Initial technical success for endoleak treatment was 96% (68 of 71). There were 13 recurrences, all of which were associated with complex endoleaks. CONCLUSIONS: Nearly half of the patients who underwent F/B-EVAR experienced an endoleak. The majority were classified as type II, with nearly a fifth associated with sac expansion. Interventions for a type II endoleak frequently led to reclassification as complex, with a concomitant type I or III endoleak not appreciated on computed tomography angiography and/or duplex. Further study is needed to determine if the primary treatment goal for complex aneurysm repair is sac stability or sac regression, as this would inform both the importance of properly classifying endoleaks noninvasively and the intervention threshold for managing type II endoleaks.