Implications and late outcomes of type II endoleaks after endovascular aneurysm repair.

OBJECTIVE: Type II endoleaks (T2ELs) are the most common cause of reintervention after endovascular aneurysm repair (EVAR). Although most resolve spontaneously, the long-term implications of T2ELs remain elusive. We aim to evaluate the impact of persistent and late T2ELs on clinical outcomes after EVAR. METHODS: This was a single-institution retrospective review of patients who underwent EVAR for degenerative infrarenal abdominal aortic aneurysm between January 2010 and June 2022 with no type I (T1EL) or III (T3EL) endoleak seen at EVAR completion. Patients were categorized based on T2EL status. Group 1 included patients with never detected or transient T2ELs (detected at EVAR completion but not after). Group 2 encompassed persistent T2ELs (seen at EVAR completion and again during follow-up) and late T2ELs (detected for the first time at any point during follow-up). Time-to-event analysis was conducted using a time-dependent approach to T2EL status. Primary outcomes included freedom from sac enlargement (SE), aneurysm-related reinterventions, and overall survival. RESULTS: A total of 803 patients met inclusion criteria. Group 1 included 418 patients (52%), of which 85% had no T2ELs and 15% had transient T2ELs. Group 2 had 385 patients; 23% had persistent T2ELs, and 77% developed a new T2EL. Patients in group 1 had a higher prevalence of smoking (88% vs 83%; P < .001), chronic obstructive pulmonary disease (33% vs 25%; P = .008), chronic kidney disease (13% vs 8%; P = .021), and a higher mean Society for Vascular Surgery score (7 vs 6 points; P = .049). No differences were found in aneurysm diameter or morphology. Mean follow-up was 5 years for the entire cohort. In Group 2, 58 patients (15%) underwent T2EL treatment, most commonly transarterial embolization. At 10 years after EVAR, Group 2 was associated with lower freedom from SE (P < .001) and abdominal aortic aneurysm-related reinterventions (P < .001) and comparable overall survival (P = .42). More T1ELs were detected during follow-up in Group 2 (6 [1%] vs 20 [5%]; P = .004), with 15 (75%) of these detected at a median of 3 years after the T2EL. No difference between groups was observed in explant (0.7% vs 2.1%; P = .130) or aneurysm rupture (0.5% vs 1.3%; P = .269) rates. CONCLUSIONS: One-half of patients treated with infrarenal EVAR developed persistent/late T2ELs, which are associated with a higher risk of SE and reinterventions. No difference in overall survival or aneurysm rupture risk was seen at 10 years, based on T2EL status or T2EL intervention. A conservative approach to T2ELs may be appropriate for most patients with absent T1ELs or T3ELs.

Comparison of bare and nonbare stent grafts during thoracic endovascular aneurysm repair of the aortic arch.

OBJECTIVE: We compared the outcomes of patients treated with nonbare stents (NBS) and proximal bare stents (PBS) endografts with a proximal landing zone in the aortic arch during thoracic endovascular aortic repair (TEVAR). METHODS: We conducted a retrospective cohort, observational, multicenter study that included 361 consecutive TEVAR procedures undertaken between November 2005 and December 2021. TEVAR patients with both BS and NBS Relay stent graft configurations with proximal landing in zones 1, 2, or 3 were enrolled. Preoperative anamnestic and morphological data, clinical outcomes, and aortic modifications 30 days after surgery and at the latest follow-up available were collected. The primary outcome was freedom from proximal endoleak (type IA) comparing the two configurations. Total and detailed endoleak rates, clinical and technical success, intraoperative additional maneuvers, major adverse events, and reinterventions were secondary outcomes. RESULTS: The median follow-up was 4.9 (interquartile range, 2.0-8.1) years. No statistically significant difference between NBS and PBS patients concerning 30-day major adverse events, retrograde aortic dissection, disabling stroke, or late type IA endoleak (10.8% vs 7.8%; P = .597). Aneurysmal disease (P = .026), PLZ diameter of >34 mm (P = .026), aortic tortuosity index of >1.4 (P = .008), type III aortic arch (P = .068), and PLZ thrombus (P = .014) identified as risk factors by univariate Cox regression analysis. PLZ thrombus was the only type IA endoleak risk factor at multivariate Cox regression (P = .016). CONCLUSIONS: We found no statistically significant difference in freedom from type IA endoleak, retrograde dissection, or disabling stroke observed between the NBS and the BS configuration of the Relay endograft. Proximal landing zone thrombotic apposition was a prominent risk factor for type IA endoleak after TEVAR.

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.

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.

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.

Midterm outcomes of endovascular repair for abdominal aortic aneurysm using the cuff-first technique to prevent type II endoleaks.

OBJECTIVE: The aim of this study was to evaluate the initial and midterm outcomes of endovascular aneurysm repair (EVAR) for abdominal aortic aneurysm (AAA) using the cuff-first technique (CFT) to prevent type II endoleak (T2EL). METHODS: CFT involves deploying an aortic cuff inside the AAA to cover the ostium of the aortic side branch vessels before deploying the main body. We performed a retrospective review of all patients undergoing EVAR with CFT or side branch embolization (SBE) for AAAs at The Jikei University Hospital between 2016 and 2022. Primary endpoint was the rate of aneurysm sac shrinkage. Secondary endpoints were procedure time, radiation exposure, technical and clinical success rates, occurrence of T2EL, and freedom from reintervention or aneurysm-related death. RESULTS: Of 406 patients who underwent EVAR for AAAs, CFT was utilized in 56 (CFT group) and SBE in 35 (SBE group); all 91 patients were included in this study. There were no differences in patient demographics between groups, but there were differences in patency rate of the inferior mesenteric artery and absent intraluminal thrombus. The technical success rate per target vessel in the CFT and SBE group was 97.8% and 91.8%, and the clinical success rate was 91.0% and 100%, respectively. The median procedure time was shorter for CFT than for SBE: CFT, 10 (interquartile range [IQR], 6-14) minutes vs SBE, 25 (IQR, 18.5-45) minutes; P < .05), and median radiation exposure was lower for CFT than for SBE (CFT, 1455 (IQR, 840-2634) mGy vs SBE, 2353 (IQR, 1552-3586) mGy; P < .05). During the median follow-up of 25 months (IQR, 12.5-47 months), sac shrinkage occurred at similar rates in both groups (CFT, 37.5% vs SBE, 40.0%; P = .812), and there were no differences in freedom from reintervention (CFT, 96.2% and 91.4% at 12 and 36 months vs SBE, 100% and 89.5% at 12 and 36 months; log-rank P = .761) and freedom from aneurysm-related death (100% at 36 months in both groups; log-rank P = .440). The odds ratio of CFT vs SBE for sac regression was calculated by adjusting for inferior mesenteric artery patency and absent intraluminal thrombus, resulting in no statistical significance (odds ratio, 1.231; 95% confidence interval, 0.486-3.122). CONCLUSIONS: CFT is feasible with a shorter procedure time and lower radiation exposure than SBE and comparable mid-term outcomes, including sac shrinkage rate, compared with SBE. We believe that CFT, if anatomically suitable, is an alternative to SBE for the prevention of T2EL during EVAR.

Efficacy of intentional undersized thoracic endovascular repair for Stanford type B aortic dissection.

OBJECTIVE: Thoracic endovascular aneurysm repair (TEVAR) is widely used for the treatment of aortic dissection. Endograft oversizing is a risk factor for stent graft-induced new entry tears and retrograde type A aortic dissection. However, there is no clear consensus on the optimal graft size selection for Stanford type B acute or subacute aortic dissection (TBAD). Herein, we examined the safety and efficacy of TEVAR using an intentionally undersized endograft to treat TBAD. METHODS: This retrospective chart review study included 82 patients who underwent TEVAR for acute or subacute Stanford TBAD between 2015 and 2022. We measured the true lumen diameter just distal to the subclavian artery and opted for a stent graft of the same diameter. In instances where deformation resulting from false lumen pressure displacement was pronounced, we measured the diameter at the site just proximal to the subclavian artery. Patients' characteristics, procedural, in-hospital, and follow-up data, and aortic remodeling were analyzed. The aortic diameter was analyzed using one-way analysis of variance followed by Dunnett's test. Survival and freedom from reintervention were estimated using Kaplan-Meier curves. RESULTS: The follow-up rate was 98.4%. The mean age was 58.3 ± 12.3 years, and 76 were men (92.7%). The mean diameters of the stent graft and native proximal landing zone were 30.9 ± 3.2 mm and 30.8 ± 3.0 mm, respectively. The oversize rate of the stent graft in relation to the native proximal aortic diameter was 0.3% ± 4.7%. In-hospital mortality was observed in one patient, retrograde type A aortic dissection in one patient, distal stent graft-induced new entry tear in zero patients, and type 1a endoleak in 22 patients (26.8%). Type 1a endoleaks, characterized by antegrade false lumen blood flow originating from the primary entry, in 12 patients spontaneously disappeared within 1 year of follow-up. According to aortic remodeling, 59 patients (86.8%) achieved complete aortic remodeling at the aortic arch level and 51 (75.0%) at the eighth thoracic vertebral level. The diameters of the aortic arch and descending aorta were significantly reduced compared with the postoperative measurements (P <.001). Survival rates were 97.5% and 93.6% at 1 and 3 years, respectively. Freedom from reintervention was 84.7% and 84.7% at 1 and 3 years, respectively. CONCLUSIONS: Intentionally undersized TEVAR was safe and achieved acceptable aortic remodeling despite a high rate of type 1a endoleaks. A type 1a endoleak was acceptable as it primarily diminished during the mid-term follow-up.

Predictors for reintervention and survival during long-term follow-up after thoracic endovascular aortic repair for descending thoracic aortic aneurysm.

BACKGROUND: Several studies have reported short- and intermediate-term outcomes after thoracic endovascular aortic repair (TEVAR) for descending thoracic aortic aneurysm (DTAA); however, reports on long-term (10 years) outcomes are sparse. Therefore, the aim of this study was to analyze predictors impacting long-term outcome after TEVAR for DTAA. METHODS: Databases from four academic institutions were reviewed and consecutive cases of TEVAR for DTAA between 1999 and 2021 were included in this retrospective multicenter study (case series). Ethical approval from the institutional review board was obtained and patient demographics and treatment data, as well as follow-up information were retrieved and analyzed. RESULTS: We identified 305 patients (mean age, 72 ± 10 years) who were treated with TEVAR for degenerative DTAA with a mean aortic diameter of 64 mm. Altogether 445 endografts were implanted via femoral access (93%) with a technical success of 94%. Operative mortality, stroke rate, and rate of spinal cord ischemia were 6% (5% for intact, 12% for ruptured DTAA), 4%, and 3%, respectively. Kaplan-Meier estimates for overall survival rates were 76%, 59% and 34% at 1, 5 and 10 years and freedom from reintervention rates were 84%, 73% and 58% at 1, 5 and 10 years, respectively. In multivariate analysis, American Society of Anesthesiologists grade 3 to 5 and nonelective case were identified as predictors for death, whereas as fusiform DTAA, proximal landing zone 2, and hypertension, but not device generation, were predictive for reintervention. CONCLUSIONS: This study is, to date, the largest reporting long-term (10 years) outcome on TEVAR for DTAA. We found acceptable rates for long-term survival and freedom from reintervention that were independent of endovascular device generation.

Clinical impact of proximal fixation augmentation using the Najuta thoracic fenestrated stent graft during endovascular treatment for distal aortic arch aneurysm.

OBJECTIVE: Prevention of late type Ia endoleaks is the main concern in thoracic endovascular aortic aneurysm repair (TEVAR) for thoracic aortic aneurysm. Since 2017, we have performed zone 0 TEVAR with proximal fixation augmentation using a Najuta thoracic fenestrated stent graft in addition to zone 2 TEVAR for distal arch aneurysms. We report the early and midterm outcomes of TEVAR performed using this strategy. METHODS: This single-center retrospective study enrolled 386 cases of TEVAR for thoracic aortic disease between January 2013 and December 2020. Patients with thoracic aortic aneurysm treated by TEVAR landing at zone 2 was referred to as the standard group, whereas those treated by TEVAR landing at zone 0 using a Najuta fenestrated stent graft in addition to zone 2 TEVAR was referred to as the augmentation group. We retrospectively compared the clinical outcomes between the two groups. The primary end point was secondary intervention for postoperative type Ia endoleaks. Secondary end points were technical success, aneurysm-related death, and major adverse events (MAEs), including stroke, paraplegia, endoleaks, and secondary interventions. RESULTS: We performed TEVAR in 41 and 30 cases in the standard and augmentation groups, respectively. The mean aneurysm sizes in the standard and augmentation groups were 54.5 and 57.3 mm (P = .23), and the proximal neck lengths were 16.8 and 17.4 mm (P = .65), respectively. The anatomical characteristics seemed to be similar in both groups. The technical success rate in both groups was 100%. Three cases in the standard group had MAEs, including two stroke and one brachial artery pseudoaneurysm; whereas two cases had MAEs in the augmentation group, including one stroke and one paraplegia. There was no 30-day mortality or retrograde type A dissection in both groups. The mean observation periods in the standard and augmentation groups were 46 months (range, 1-123 months) and 35 months (range, 1-73 months), respectively. At 36 and 60 months after the procedure, the freedom from aneurysm-related death was 97.6% and 97.6% in the standard group, 100.0% and 100.0% in the augmentation group (P = .39); and the freedom from reintervention for type Ia endoleaks was 79.2% and 65.2% in the standard group, 100.0% and 100.0% in the augmentation group (P = .0087). A statistically significant decrease in reinterventions for type Ia endoleaks was observed in the augmentation group. CONCLUSIONS: Proximal fixation augmentation using the Najuta fenestrated stent graft during TEVAR for distal arch aneurysm is effective in preventing the postoperative late type Ia endoleaks.

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.

Initial two-day blood pressure management after endovascular aneurysm repair improves midterm outcomes by reducing the incidence of early type II endoleak.

OBJECTIVE: The aim of this study was to evaluate midterm outcomes of our novel strategy of postoperative initial 2-day blood pressure management (BPM) after endovascular aneurysm repair (EVAR) for the prevention of subsequent type II endoleak (T2EL) in a single-center series. METHODS: Between 2008 and 2014, 137 patients who underwent EVAR for abdominal aortic aneurysm (AAA) were reviewed. Starting from 2013, the mean blood pressure was maintained between 75 and 90 mmHg for the initial 24 hours after EVAR followed by systolic pressure controlled below 120 mmHg during the next 24 hours in the treatment group (n = 76). The incidence of T2EL detected at 7 days, reintervention, and AAA sac diameter up to 5 years after EVAR were compared with those of the control group comprising of 60 consecutive patients who underwent standard EVAR without BPM prior to 2013. RESULTS: Between the treatment group and the control group, significant differences were achieved in the incidence of T2EL at 7 days (19.7% vs 40.0%; P = .009), a mean decrease of AAA sac diameter at 1-year (-5.1 ± 4.9 vs -2.2 ± 6.7 mm; P = .013) and 2-year (-5.4 ± 7.7 vs -1.7 ± 10.8 mm; P = .045). In addition, there was a significant decrease in the incidence of T2EL detected at 7 days with the use of the Gore Excluder with 22.7% in the treatment group vs 80.0% in the control group (P < .001), which resulted in a significant decrease in the aneurysm sac diameter up to 4 years after EVAR. Survival rate without AAA sac enlargement at 5 years after EVAR (83.0% vs 70.0%; P = .021) in the treatment group was significantly higher than that of the control group, whereas no significant differences were observed in the freedom rates of reintervention, T2EL-related reintervention, and all-cause mortality between the groups. CONCLUSIONS: Postoperative initial 2-day BPM had a preventive effect on AAA sac enlargement until midterm periods, by reducing the incidence of T2EL at 7 days after EVAR. The usage of Gore Excluder under BPM was especially associated with sustained positive effects until the midterm follow-up.

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.

Use of physician-modified inverted limb in conjunction with Zenith fenestrated stent graft to rescue failed previous endovascular and open repair.

OBJECTIVE: To evaluate outcomes and performance of inverted limbs (ILs) when used in conjunction with Zenith fenestrated stent grafts (Zfens) to treat patients with short distance between the lowest renal artery (RA) and aortic or graft bifurcation (A/GB). METHODS: This study was a multicenter, retrospective review of prospectively maintained database of patients with complex aortic aneurysms, failed endovascular aneurysm repair (EVAR), or open surgical repair (OSR) with short distance between LRA and A/GB treated using a combination of Zfen and an IL between 2013 and 2023. Endpoints included technical success, aneurysm sac regression, long-term device integrity, and target vessel patency. We defined technical success as implantation of the device with no endoleak, conversion to an aorto-uni-iliac or OSR. RESULTS: During this time, 52 patients underwent endovascular rescue of failed repair. Twenty (38.5%) of them required relining of the failed repairs using IL due to lowest RA to A/GB length restrictions. Two patients had undergone rescue with a fenestrated cuff alone but developed type III endoleaks. One patient with no previous implant had a short distance between the lowest RA and aortic bifurcation to accommodate the bifurcated distal device, and two patients had failed OSR or anastomotic pseudoaneurysms. The majority (94%) were men with a mean age of 76.8 ± 6.1 years. The mean aortic neck diameter and aneurysm size were 32 ± 4 cm and 7.2 ± 1.3 cm, respectively. The median time laps between initial repair and failure was 36 months (interquartile range [IQR], 24-54 months). Sixteen patients (80%) were classified as American Society of Anesthesiologists class III, whereas four were class IV. Seventy-eight vessels were targeted and successfully incorporated. Technical success was 100%, and median estimated blood loss was 100 mL (IQR, 100-200 mL). Mean fluoroscopy time and dose were 61 ± 18 minutes and 2754 ± 1062 mGy, respectively. Average hospital length of stay was 2.75 ± 2.15 days. Postoperative complication occurred in one patient who required lower extremity fasciotomy for compartment syndrome. At a median follow-up of 50 months (IQR, 18-58 months), there were no device migration, components separation, aneurysmal related mortality, and type I or type III endoleak. Aneurysm sac regression (95%) or stabilization (5%) was observed in all patients, including in four patients (25%) with type II endoleak. CONCLUSIONS: The use of IL in conjunction with Zfen to treat patients with short distance between the lowest RA and A/GB is safe, effective, and has excellent long-term results. The technique expands the indication of Zfen, especially in patients with failed previous EVAR.

Five-year follow-up of randomized clinical trial for pre-emptive inferior mesenteric artery embolization during endovascular aneurysm repair.

OBJECTIVE: Type II endoleak (T2EL) is the most common type of endoleak after endovascular aneurysm repair (EVAR) and a common indication for reintervention due to late sac enlargement. Although pre-emptive embolization of the inferior mesenteric artery (IMA) has been proposed to prevent this, no studies have prospectively demonstrated its efficacy. This study aimed to prove the validity of IMA embolization during EVAR in selective cases by analyzing the mid-term outcomes of a randomized clinical trial (RCT). METHODS: This single-center, parallel-group, non-blinded RCT included participants at high risk of T2EL, characterized by a patent IMA in conjunction with one or more following risk factors: a patent IMA ≥3 mm in diameter, lumbar arteries ≥2 mm in diameter, or an aortoiliac-type aneurysm. The participants were randomly assigned to two groups in a 1:1 ratio: one undergoing EVAR with IMA embolization and the other without. The primary endpoint was T2EL occurrence. The secondary endpoints included aneurysm sac changes and reintervention. In addition to RCT participants, outcomes of patients with low risk of T2EL were also analyzed. RESULTS: The embolization and non-embolization groups each contained 53 patients. Five-year follow-up after the last patient enrollment revealed that T2ELs occurred in 28.3% and 54.7% of patients in the IMA embolization and non-embolization groups, respectively (P = .006). Both freedom from T2EL-related sac enlargement ≥5 mm and cumulative incidence of sac shrinkage ≥5 mm were significantly higher in the IMA embolization group than in the non-embolization group (95.5% vs 73.6% at 5 years; P = .021; 54.2% vs 33.6% at 5 years; P = .039, respectively). The freedom from T2EL-related sac enlargement ≥10 mm, an alternative indicator for T2EL-related reintervention, showed similar results (100% vs 90.4% at 5 years; P = .019). Outcomes in the low-risk group were preferable than those in the non-embolization group and comparable to those in the IMA embolization group. CONCLUSIONS: A lower threshold for pre-emptive IMA embolization when implementing EVAR would be more appropriate if limited to patients at high risk of T2ELs.

Unenhanced computed tomography radiomics help detect endoleaks after endovascular repair of abdominal aortic aneurysm.

OBJECTIVES: To explore the feasibility of unenhanced CT images for endoleak detection of abdominal aortic aneurysm (AAA) after endovascular repair (EVAR). METHODS: Patients who visited our hospital after EVAR from July 2014 to September 2021 were retrospectively collected. Two radiologists evaluated the presence or absence of endoleaks using the combination of contrast-enhanced and unenhanced CT as the referenced standard. After segmenting the aneurysm sac of the unenhanced CT, the radiomic features were automatically extracted from the region of interest. Histogram features of patients with and without endoleak were statistically analyzed to explore the differences between the two groups. Twelve common machine learning (ML) models based on radiomic features were constructed to evaluate the performance of endoleak detection with unenhanced CT images. RESULTS: The study included 216 patients (69 ± 8 years; 191 men) with AAA, including 64 patients with endoleaks. A total of 1955 radiomic features of unenhanced CT were extracted. Compared with patients without endoleak, the aneurysm sac outside the stent of patients with endoleak had higher CT attenuation (41.7 vs. 33.6, p < 0.001) with smaller dispersion (51.5 vs. 58.8, p < 0.001). The average area under the curve (AUC) of the ML models constructed with unenhanced CT radiomics was 0.86 ± 0.05, the accuracy was 81% ± 4, the sensitivity was 88% ± 10, and the specificity was 78% ± 5. When fixing the sensitivity to > 90% (92% ± 2), the models retained specificity at 72% ± 10. CONCLUSIONS: Unenhanced CT features exhibit significant differences between patients with and without endoleak and can help detect endoleaks in AAA after EVAR with high sensitivity. CLINICAL RELEVANCE STATEMENT: Unenhanced CT radiomics can help provide an alternative method of endoleak detection in patients who have adverse reactions to contrast media. This study further exploits the value of unenhanced CT examinations in the clinical management and surveillance of postoperative abdominal aortic aneurysm. KEY POINTS: • Unenhanced CT features of the aneurysm sac outside the stent exhibit significant differences between patients with and without endoleak. The endoleak group showed higher unenhanced CT attenuation (41.7 vs 33.6, p < .001) with smaller dispersion (51.5 vs 58.8, p < .001) than the nonendoleak group. • Unenhanced CT radiomics can help detect endoleaks after intervention. The average area under the curve (AUC) of twelve common machine learning models constructed with unenhanced CT radiomics was 0.86 ± 0.05, the average accuracy was 81% ± 4. • When fixing the sensitivity to > 90% (92% ± 2), the machine learning models retained average specificity at 72% ± 10.

Large-Diameter Fenestrated Endograft Repair of Abdominal Aortic Aneurysms Is Not Associated With Medium-Term Outcomes.

INTRODUCTION: Recent data suggests that infrarenal abdominal aortic aneurysm (AAA) endovascular repair (EVAR) with large diameter grafts (LGs) may have a higher risk of endoleak and reintervention. However, this has not been studied extensively for fenestrated endovascular aneurysm repair (fEVAR). We, therefore, sought to evaluate the outcomes of patients undergoing fEVAR with large-diameter endografts. METHODS: Patients from the national Vascular Quality Initiative registry who underwent fEVAR for intact juxtarenal AAA were identified. Patients with genetic causes for aneurysms, those with prior aortic surgery, and those undergoing repair for symptomatic or ruptured aneurysms were excluded. Rates of endoleaks and reintervention at periprocedural and long-term follow-up timepoints (9-22 mo) were analyzed in grafts 32 mm or larger (LG) and were compared to those smaller than 32 mm (small diameter graft). RESULTS: A total of 693 patients (22.8% LG) were identified. Overall, demographic variables were comparable except LG exhibited a more frequent history of coronary artery disease (32.9% versus 25.4%, P = 0.037). There were no significant differences in the rates of endoleak at procedural completion. Overall survival at 5 y was no different. The rate of reintervention at 1 y was also no different (log-rank P = 0.86). CONCLUSIONS: While graft size appears to have an association with outcomes in infrarenal aneurysm repair, the same does not appear to be true for fEVAR. Further studies should evaluate the long-term outcomes associated with LG which could alter the approach to repair of AAA with large neck diameters traditionally treated with standard infrarenal EVAR.

Serious Failure Modes After EVAR Are Device Specific.

OBJECTIVES: Type I and III endoleaks following endovascular aneurysm repair (EVAR) can lead to catastrophic events that require major re-interventions. We reviewed our experience with aortic endograft re-interventions for type I and III endoleaks and other serious failures among different devices. METHODS: We retrospectively reviewed patients with a prior EVAR who underwent open conversion (OC) or major endovascular intervention (MEI) (re-lining, cuff/limb extension, parallel graft) for type I/III endoleaks at our institution from 2002 to 2019. Baseline characteristics, procedural details, re-interventions, and outcomes were collected. RESULTS: A total of 229 patients (194 men) underwent re-interventions for type I and III endoleaks after EVAR (90 OC, 139 MEI) for devices implanted between 1997 and 2019. Average age at re-intervention was 78±8.5 years. A total of 135 (59%) were implanted at our institution, whereas 93 (41%) were referred. Median time to re-intervention was 4 years with 25% to 75% interquartile range (IQR) of 2.2-6.6 years. There was no significant difference in baseline demographics or type of re-interventions (OC/MEI) between device types. 42/229 (18%) presented with ruptured aneurysms, 20/229 (9%) were symptomatic, whereas the rest presented with asymptomatic radiographic findings. Type 1A endoleak was present in 146/229 (63.8%-72 with proximal migration), type IB in 46/229 (20.1%), type IIIA in 37/229 (16.6%), type IIIB in 15/229 (6.5%), and persistent aneurysm sac growth with no radiographic evidence of an endoleak in 6/229 (2.6%). Devices included most commercial products: AFX, Excluder, AneuRx, Ancure, Endurant, and Zenith. A smaller number of investigational devices accounted for the rest. Type 1A endoleak was the most common indication for re-intervention among all devices except for AFX and ancure devices, proximal migration was a frequent presentation with AneuRx. AFX devices more frequently presented with a type III and ancure devices more frequently presented with a type IB endoleak. CONCLUSIONS: Serious failure modes after EVAR differ between endografts and occur throughout the follow-up period. This is important to guide targeted interrogation of surveillance studies and follow-up schedules, even for discontinued devices, as well as comparisons between various series and estimation of EVAR failure rates. CLINICAL IMPACT: Surveillance after EVAR is critical for long term success of the repair, understanding of the differential modes of failure of every graft available is important in the longitudinal evaluation of these endografts. Equally important is the understanding of the modes of failure of legacy endografts that are no longer on the market but still being followed, in order to be able to tailor a surveillance regiemn and the evntual repair if needed.

Impact of Stent Size Selection and Vessel Evaluation on Skull Base Cerebrovascular Diseases Treated With Willis Covered Stents: A Multicenter Retrospective Analysis.

PURPOSE: This study aimed to evaluate the impact of the diverse stent size selection on the clinical and angiographic outcomes of Willis covered stent (WCS) for the treatment of skull base cerebrovascular diseases. MATERIALS AND METHODS: A total of 147 patients with 151 skull base cerebrovascular diseases treated with WCS in 3 centers between January 2015 and July 2022 were included in this study. Several parameters depicting stent size and parent artery condition were incorporated into the analysis of the outcomes. RESULTS: Complete occlusion was found in 106 cases (68.2%) immediately after deployment and 126 cases (83.4%) after technical adjustment. In the multivariate logistics analysis, the difference between stent diameter and parent artery diameter (DD) was significantly associated with immediate endoleak without adjustment (odds ratio [OR]=0.410; p=0.005) and late endoleak (OR=0.275; p=0.028). In addition, differences between stent diameter and parent artery diameter at wide landing point (DSW) and differences between stent diameter and parent artery diameter at narrow landing point (DSN) was also was significant associated with immediate endoleak without adjustment and balloon re-dilation respectively. CONCLUSIONS: This study demonstrated that the diameter selection of the WCS was associated with the occurrence of endoleak during the treatment of skull base cerebrovascular diseases. Precise selection and evaluation of stent size and vessel condition were significant factors for skull base cerebrovascular diseases treated by WCS. CLINICAL IMPACT: This study demonstrates a significant association between the diameter selection of the Willis covered stent (WCS) and the occurrence of endoleak in the management of skull base cerebrovascular diseases. The results offer valuable medical evidence that can inform stent selection for WCS. The study emphasizes the significance of precise evaluation of stent size and vessel condition as crucial factors in WCS procedures. These findings underscore the importance of meticulous consideration and individualized approaches to stent selection, ultimately improving treatment outcomes in clinical practice.

Outcomes of Late Partial Conversion With Graft Replacement for Sac Enlargement After Endovascular Abdominal Aortic Aneurysm Repair.

PURPOSE: Outcomes of late open conversion with graft replacement for enlargement after endovascular aortic repair remain unclear. Here, we report the outcomes of graft replacement after endovascular aortic repair. MATERIALS AND METHODS: Fourteen patients who underwent graft replacement after endovascular aneurysm repair between November 2016 and October 2022 were included. Graft replacement was indicated in cases of rupture and enlargement of the aneurysm sac and when reintervention with endovascular therapy could not be performed. RESULTS: The mean age at graft replacement was 80 ± 7 years. The follow-up period from endovascular aortic repair to graft replacement was 73 ± 41 months. The endoleaks that caused enlargement of the aneurysm sac were type I in 8 patients and type II in 6 patients. Ruptures were observed in 5 patients. One patient had paraplegia as a postoperative complication, and 2 patients died within 30 days. Morbidity and mortality were observed in cases of rupture, and no morbidity or mortality was observed in any elective surgery cases. CONCLUSION: Late open conversion with graft replacement after endovascular aortic repair is a feasible elective surgery. However, morbidity and mortality have been observed in cases of rupture. CLINICAL IMPACT: In elective surgery, postoperative outcomes are good for late open conversion with graft replacement after endovascular aortic repair. On the other hand, morbidity and mortality were observed in case of rupture. Therefore, it is important to perform elective surgical reintervention at the appropriate time.

Long-Term Outcomes of Endovascular Repair Within and Outside the Instructions for Use in Korean Patients With Abdominal Aortic Aneurysm.

OBJECTIVE: Endovascular aneurysm repair (EVAR) has been used worldwide to treat abdominal aortic aneurysms (AAAs). Outcomes after EVAR within and outside the instruction for use (IFU) remain controversial. We analyzed long-term outcomes of EVAR within-the-IFU compared with that outside-the-IFU and baseline clinical/anatomical characteristics that influence outcomes of EVAR. METHODS: The study included 546 patients who underwent EVAR for infrarenal AAA from 1997 to 2021 at 2 Korean medical centers. The primary endpoint was graft-related adverse events (GRAEs), including type 1 or 3 endoleak, reintervention (included open conversion), aneurysm sac enlargement, aneurysm-related mortality (ARM), rupture, stent-graft migration, and stent thrombotic occlusion. RESULTS: The patients who underwent EVAR outside the IFU were 287 (52.6%). A neck angle of >60° was most common outside the IFU criteria (n=146, 50.9%). This study revealed that patients outside the IFU had a higher rate of GRAEs compared with patients within the IFU (hazard ratio [HR]: 1.879; 95% confidence interval [CI]: 1.045-2.386). A neck angle of >60° was a significant risk factor for GRAEs (adjusted HR: 2.229; 95% CI: 1.418-3.503), type 1 or 3 endoleak (adjusted HR: 2.640; 95% CI: 1.343-5.189), and reintervention (adjusted HR: 1.891; 95% CI: 1.055-3.388). CONCLUSIONS: Our study revealed EVAR with outside the IFU was associated with increased GRAEs, mainly attributed to endoleak and ARM, compared with EVAR with within the IFU. In addition, severe neck angulation was an independent risk factor for GRAEs, type 1 or 3 endoleak, and reintervention. CLINICAL IMPACT: Our study revealed endovascular aneurysm repair (EVAR) with outside-the-instruction for use (IFU) was associated with increased graft-related adverse events (GRAEs) compared with EVAR with within-the-IFU. In the low-risk population, the incidence of GRAEs and Aneurysm related mortality were higher in the outside-the-IFU group rather than within-the-IFU group. In addition, severe neck angulation was an independent risk factor for GRAEs, type 1 or 3 endoleak and reintervention.