Inferior Mesenteric Artery Embolization Research Articles

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

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). 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. The embolization and non-embolization groups each contained 53 patients. Five-year follow-up after the last patient enrolment 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). 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. A lower threshold for pre-emptive IMA embolization when implementing EVAR would be more appropriate if limited to patients at high risk of T2ELs.

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

ObjectiveTo 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. MethodsBetween 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. ResultsAmong 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. ConclusionsPre-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

ObjectiveType 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. MethodsThis 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. ResultsType 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±5.5months). 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 two 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. ConclusionsTwo-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.

Clinical Significance of Lumbar Artery Embolization in Addition to Inferior Mesenteric Artery Embolization to Reduce Persistent Type 2 Endoleak at Endovascular Aneurysm Repair

Persistent type 2 endoleak (T2EL) after endovascular aneurysm repair (EVAR) leads to a higher likelihood of reintervention, sac enlargement, and other adverse outcomes. Although embolization of the inferior mesenteric artery (IMA-E) can decrease T2EL, additional effects of lumbar artery embolization (LA-E) remain undetermined. The aim was to evaluate the effects of pre-emptive LA-E at EVAR on the incidences of persistent T2EL and related complications. Safety and radiation exposure were also analyzed. Consecutive patients who underwent EVAR for abdominal aortic aneurysm between 2013 and 2021 were included. Pre-emptive embolizations were IMA-E before April 2018 and IMA-E plus LA-E thereafter. Patients with occluded IMA/LA, severe renal dysfunction, short life expectancy, or contraindication to contrast agents were not considered for pre-emptive embolization (NO-E). The incidence of T2EL, sac enlargement (>5 mm), reintervention, and other adverse events were compared among three different strategies, as well as radiation time and dose-area products. There were 243, 216, and 158 patients in the NO-E, IMA-E, and LA-E groups, respectively. Statistical differences in the backgrounds were found between age, sex, respiratory impairment, chronic kidney disease, hostile abdomen, aneurysm diameter, proximal neck length, right distal landing length, and device used. T2EL occurred at 20.7%, 24.0%, and 9.7% in the NO-E, IMA-E, and LA-E groups at 1 year, 27.7%, 30.8%, and 12.1% at 2 years, and 29.3%, 30.7%, and 9.8% at 3 years, respectively. After adjustment for confounding factors, LA-E compared with IMA-E was less likely to develop T2EL at 1 year (odds ratio [OR]: 0.31, 95% confidence interval [CI]: 0.14-0.66), 2 years (OR: 0.28, CI: 0.13-0.61), and 3 years (OR: 0.23, CI: 0.08-0.66). Similarly, LA-E compared with NO-E was associated with less T2EL at 1 year (OR: 0.45, CI: 0.21-0.96), 2 years (OR: 0.36, CI: 0.17-0.78), and 3 years (OR: 0.29, CI: 0.10-0.87). Reintervention until 3 years was less frequent after LA-E compared with IMA-E (OR: 0.18, CI: 0.05-0.63) and NO-E (OR: 0.15, CI: 0.04-0.50). Sac shrinkage was larger after LA-E compared with IMA-E (differences, 2.9 ± 1.4 mm) and NO-E (differences, 2.9 ± 1.4 mm). Surgical conversion, sac enlargement, rupture, and aneurysm-related death were not statistically different. No embolization-related complication was reported. Radiation time (minutes) and dose-area products (Gycm2) for NO-E, IMA-E, and LA-E were 61 ± 47, 58 ± 39, and 76 ± 43 (P = .0002) and 432 ± 330, 471 ± 345, and 640 ± 454 (P < .0001), respectively. LA-E in addition to IMA-E can decrease persistent T2EL and reintervention over 3 years. Although excessive radiation exposure limits routine use of LA-E and warrants future innovation on imaging guidance, longer-term effects of LA-E are encouraging.Table IBackground characteristicsNone (n = 243)IMA-E (n = 216)IMA+LA-E (n = 158)P valueAge, mean ± SD77.0 ± 0.674.8 ± 0.675.6 ± 0.7.02Age, median (IQR)78 (72-83)76 (69-81)77 (70-82)Sex, male, No. (%)184 (75.7)187 (86.6)125 (79.1).01HT, No. (%)206 (85.1)181 (83.8)124 (78.5).21DM, No. (%)34 (14.1)33 (15.3)23 (14.6).93Stroke, No. (%)44 (18.2)27 (12.5)30 (19.0).16CAD, No. (%)65 (26.9)50 (23.2)30 (19.0).19Respiratory impairment, No. (%)87 (36.0)76 (35.2)75 (47.5).03Smoking, No. (%)193 (79.4)178 (82.4)118 (74.7).41 Ex/current124/69115/6383/35CKD, No. (%)122 (50.2)85 (39.4)79 (50.0).03 3/4/594/20/873/9/372/5/2Hostile abdomen, No. (%)121 (50.0)95 (44.0)48 (30.4).0005Aneurysm diameter, mean ± SD, mm52.4 ± 9.750.0 ± 7.950.2 ± 7.8.002Proximal neck diameter, mean ± SD, mm22.7 ± 3.522.2 ± 3.722.1 ± 3.3.21Proximal neck length, mean ± SD, mm26.1 ± 12.731.1 ± 15.027.7 ± 12.9.0005Right leg landing CIA/EIA168/67166/4697/58.02 CIA diameter, mean ± SD, mm13.7 ± 2.914.1 ± 2.613.8 ± 2.7.54 EIA diameter, mean ± SD, mm9.1 ± 1.610.0 ± 2.89.8 ± 2.1.08Left leg landing CIA/EIA189/44181/31124/31.38 CIA diameter, mean ± SD, mm13.5 ± 3.513.8 ± 3.114.0 ± 2.8.33 EIA diameter, mean ± SD, mm9.6 ± 2.49.9 ± 2.510.2 ± 2.7.57Device, n (%).008 Endurant133 (54.7)151 (69.9)86 (54.4) Excluder86 (35.4)53 (24.5)56 (35.4) Zenith9 (3.7)4 (1.9)10 (6.3) Others15 (6.2)8 (3.7)6 (3.8)CAD, Coronary artery disease; CIA, common iliac artery; CKD, chronic kidney disease; DM, diabetes mellitus; EIA, external iliac artery; HT, hypertension; IMA-E, embolization of the inferior mesenteric artery; IMA+LA-E, inferior mesenteric artery lumbar artery embolization; IQR, interquartile range; SD, standard deviation.Boldface P values represent significance P < .05. Open table in a new tab Table IIMultivariate analysis adjusted for imbalanced factors in the backgroundsComparisonOR95% CIP valueType 2 endoleak 1 yearIMA vs none1.450.83-2.55.19IMA+LA vs none0.450.21-0.96.04IMA+LA vs IMA0.310.14-0.66.003 2 yearsIMA vs none1.270.74-2.18.39IMA+LA vs none0.360.17-0.78.009IMA+LA vs IMA0.280.13-0.61.001 3 yearsIMA vs none1.300.71-2.38.40IMA+LA vs none0.290.10-0.87.03IMA+LA vs IMA0.230.08-0.66.007Age1.051.01-1.09.009Reintervention Until 3 yearsIMA vs none0.810.44-1.53.52IMA+LA vs none0.150.04-0.50.002IMA+LA vs IMA0.180.05-0.63.008CI, Confidence interval; IMA, inferior mesenteric artery; LA, lumbar artery; OR, odds ratio.Boldface P values represent significance P < .05. Open table in a new tab

Application of meandering mesenteric artery in vascular surgery

In recent years, the therapeutic concepts and surgical methods of the meandering mesenteric artery involved in atherosclerosis have been reported in the literature, and the importance of this lateral branch circulation in the field of vascular surgery has received more attention. With the improvement of imaging techniques, the discovery rate of this collateral circulation increased. In the presence of major iliac artery occlusion, the meandering mesenteric artery may serve as an important collateral circulation to relieve ischemia in the visceral or lower extremities. The meandering mesenteric artery may also lead to type Ⅱ internal leakage after endovascular repair, while the embolization of inferior mesenteric artery may be performed through the meandering mesenteric artery. The role of meandering mesenteric arteries in vascular surgery needs further study.

Abstract 9371: Effectiveness of Endovascular Aneurysm Repair With Inferior Mesenteric Artery Embolization From Mid-Term Outcome of a Randomized Controlled Trial

Introduction: Adequate management of type II endoleak (T2EL) has been widely discussed, and inferior mesenteric artery (IMA) embolization before endovascular aneurysm repair (EVAR) has been reported to reduce the T2EL. However, there have been no randomized controlled trials (RCT) confirming the efficacy. Thus, this study aimed to evaluate the effect of IMA embolization during EVAR in patients at high risk of T2EL in an RCT. Methods: This study included patients scheduled for elective EVAR between September 2014 and March 2018. Patients at high risk of T2EL (IMA patency with IMA ≥ 3 mm, LAs ≥ 2 mm, or an aortoiliac-type aneurysm) were prospectively randomized to receive EVAR with or without IMA embolization. The primary endpoint was T2EL occurrence during follow-up. The secondary endpoints were aneurysmal sac changes, adverse events from IMA embolization, and reintervention rate due to T2EL. Results: A total of 106 patients were randomized to the embolization group (group A, n = 53) or the nonembolization group (group B, n = 53). The technical success rate of IMA embolization was 88.7%, and no complications related to IMA embolization were observed. During the mean follow-up period—50.2 ± 21.9 months in group A and 52.9 ± 23.1 months in group B—the incidence of T2EL was significantly lower in the embolization group (23.9% in group A vs. 53.8% in group B; P &lt; 0.0001). Sac diameter changes, the incidence of aneurysmal sac growth (≥5 mm) related to T2EL, and freedom from sac enlargement (≥5 mm) related to T2EL at 5 years were –6.5 ± 8.9 mm vs. –1.1 ± 13.1 mm, 6.5% vs. 25.0%, and 97.5% vs. 72.0% in groups A and B, respectively (P = 0.015; P = 0.025; P = 0.018), which show that both shrinkage of aneurysm and freedom from sac enlargement are significantly higher in group A. Although no significant difference was observed in the reintervention rate due to T2EL (0% in group A vs. 2% in group B; P = 0.344), a significant difference in sac enlargement (≥10 mm) related to T2EL was observed (0% in group A vs. 13.5% in group B; P = 0.010), suggesting that reintervention would need to be considered. Conclusions: The results demonstrated the effectiveness of IMA embolization during EVAR in high-risk patients for the prevention of T2EL, which is suggested for avoiding aneurysmal sac enlargement related to T2EL.

Effectiveness of Inferior Mesenteric Artery Embolization on Type II Endoleak-Related Complications after Endovascular Aortic Repair (EVAR): Systematic Review and Meta-Analysis.

Type II endoleak is one of the most common and problematic complications after endovascular aneurysm repair. It has been suggested that the inferior mesenteric artery (IMA) embolization could prevent further adverse events and postoperative complications. This article is a systematic review and meta-analysis following PRISMA guidelines. The Medline, PubMed, Embase, and Cochrane databases were used to identify studies that investigated the effect of IMA embolization on the occurrence of type II endoleaks and secondary interventions in a group of patients with abdominal aortic aneurysm who underwent EVAR compared with results after EVAR procedure without embolization. A random effects meta-analysis was performed. Of 3510 studies, 6 studies involving 659 patients were included. Meta-analysis of all studies showed that the rate of secondary interventions was smaller in patients with IMA embolization (OR, 0.17; SE, 0.45; 95% CI, 0.07 to 0.41; p < 0.01; I2 = 0%). The occurrence of type II endoleaks was also smaller in the embolization group (OR, 0.37; SE, 0.21; 95% CI, 0.25 to 0.57; p < 0.01; I2 = 16.20%). This meta-analysis suggests that IMA embolization correlates with lower rates of type II endoleaks and secondary interventions.

Inferior mesenteric artery embolization ahead of rectal cancer surgery: AMIREMBOL pilot study.

Ischaemic conditioning in rectal cancer surgery by preoperative embolization of the inferior mesenteric artery is feasible and safe. It seems to protect from ischaemic stress during the surgical procedure.

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.

Significance of preoperative thrombus burden in the prediction of a persistent type II and reintervention after infrarenal endovascular aneurysm repair

BackgroundPersistent type II endoleak has necessitated prolonged surveillance and is a reason for reintervention after infrarenal endovascular aneurysm repair (EVAR). The aim of this study was to assess the association of thrombus burden (TB) within the aneurysmal sac in the prediction of a persistent type II endoleaks. MethodsConsecutive patients who underwent infrarenal EVAR from October 2009 to October 2017 in a single vascular network were included. TB was assessed on preoperative computed tomography angiogram and was defined as a percentage of thrombus across the maximal sac diameter in comparison with the luminal diameter measured orthogonally at the same level. Patients were categorized into three groups: low TB (<25%), medium TB (25%-50%), and high TB (>50%). All patients underwent postoperative EVAR surveillance comprising computed tomographic angiography or duplex ultrasound imaging. Type II endoleak observed for more than 1 year was defined as persistent type II endoleak. Odds ratio (OR) and Student’s t-test were used to determine significance. ResultsSome 275 EVARs were performed in the study period. A total of 45 procedures were excluded because of either iliac-only intervention (n = 9), no preoperative information (n = 7), abandoned (n = 1), or less than 1 year’s follow-up data (n = 28). For the 230 procedures included, the median follow-up was 43 (12-102) months. There were no significant differences between the groups for age, gender, and comorbidities nor preoperative sac diameter. There was high interobserver reliability with a kappa value of 0.89 (0.84-0.94) with a total discordance of 7% across the cohorts. Persistent type II endoleak occurred significantly more frequently with reduced TB: 41% of the low TB cohort compared with 4% of the high TB cohort (OR, 15.36 [3.5-67.3]; P = .0003). Reintervention was also significantly more likely to occur in the presence of a persistent type II endoleak compared with its absence; n = 12 of 13 (92%) patients who underwent reintervention had a persistent type II endoleak (OR, 43.4 [5.5-242]; P = .0003). Sac size reduction was significantly greater in medium TB and high TB cohorts when compared with low TB: −25% and −27% vs −15% (P = .0046 and P < .0001). Decreased TB was associated with a significant increase in inferior mesenteric artery (IMA) patency, the mean TB, where the IMA was patent, being 29% compared with 40% where the IMA was occluded P < .0001. When considered together, patients with a low TB and a patent IMA were even more likely to have a persistent type II endoleak when compared with those with a high TB and an occluded IMA (OR, 34.1 [1.99-583]; P = .015). ConclusionsLow TB is associated with increased rates of persistent type II endoleak, especially in the presence of a patent IMA. High TB is associated with increased sac regression and low reintervention rates. TB can be assessed reliably and could be used for risk stratification in the planning of infrarenal EVAR. Pre-emptive embolization of IMA or lumbar vessels in those with low TB may be beneficial. TB could be a useful tool for designing a post-EVAR surveillance regimen.

Inferior Mesenteric Artery Associated Type II Endoleaks: Are They Predictable?

Abstract Purpose This study aims to evaluate the relationship between inferior mesenteric artery (IMA) diameter and risk of type II endoleak. Subjects and Methods: A retrospective study design to review all EVARs performed over a 4-year period at a tertiary care center. Out of the total cohort of 400 patients who underwent EVAR, 41 patients (10.3%) developed type II endoleak. The mean IMA ostial diameter for patients with type II endoleak secondary to IMA contributories was 4mm, while the mean IMA diameter for patients with lumbar arteries contributing to the type II endoleak was 3.7mm. Results Statistical analysis using a paired t-test did not show a statistically significant difference in the IMA ostial diameter between the two groups. Conclusion There is no significant correlation between preprocedural IMA ostium diameter and type II endoleak development and hence, preprocedural IMA embolization is not an appropriate prophylactic management strategy.

Outcomes of Preventive Embolization of the Inferior Mesenteric Artery during Endovascular Abdominal Aortic Aneurysm Repair

PurposeTo evaluate the impact of preemptive inferior mesenteric artery (IMA) embolization on outcomes of endovascular abdominal aortic aneurysm (AAA) repair (EVAR). Materials and MethodsFrom January 2015 to July 2017, all patients undergoing elective EVAR or fenestrated EVAR (F-EVAR) for asymptomatic AAA in a single tertiary hospital were retrospectively included. Three groups of patients were defined: patients with a patent IMA who underwent embolization during EVAR/F-EVAR (group 1), those with a patent IMA who did not undergo embolization during EVAR/F-EVAR (group 2), and those with a chronically occluded IMA (group 3). Preoperative aortic morphology, demographics, and procedural details were recorded. Aneurysmal growth (≥5 mm), reintervention, and overall mortality rates were analyzed using multivariate proportional hazard multivariate modeling. Propensity scores were constructed, and inverse probability weighting was applied to a new set of multivariate analyses to perform a sensitivity analysis. ResultsA total of 266 patients (male, 95% [n = 249]) with a median age of 70 (65–77) years were included, with F-EVAR procedures comprising 87 (32.7%) of the interventions. There were 52, 142, and 72 patients in groups 1, 2, and 3, respectively. Changes in aneurysmal sac size did not differ between groups, nor did overall survival or reintervention rates at 24 months. IMA embolization was not identified as an independently protective factor for aneurysmal growth during follow-up (relative risk [RR] = 2.82/mm [0.96–8.28], P = .060), whereas accessory renal arteries (RR = 5.07/mm [1.72–14.96], P = .003) and a larger preoperative aneurysmal diameter (RR = 1.09/mm [1.03–1.15], P = .004) were independent risk factors for sac enlargement. ConclusionsPreventive embolization of the IMA during EVAR or F-EVAR did not promote aneurysmal sac shrinking or decrease the reintervention rate at 2-year follow-up.

Society for Vascular Surgery implementation of clinical practice guidelines for patients with an abdominal aortic aneurysm: Endoleak management

Society for Vascular Surgery implementation of clinical practice guidelines for patients with an abdominal aortic aneurysm: Endoleak management

Surgical treatment patterns and clinical outcomes of patients treated for expanding aneurysm sacs with type II endoleaks after endovascular aneurysm repair

ObjectivePersistent type II endoleaks (T2ELs) after endovascular aneurysm repair (EVAR) with sac growth have been associated with adverse events, including rupture. Whereas intervention in the presence of aneurysm growth has become an accepted treatment paradigm for T2ELs, the efficacy and clinical success of such interventions remain unclear. Therefore, we examined the treatment patterns and clinical outcomes of patients undergoing T2EL interventions after EVAR. MethodsWe performed a retrospective review of all patients treated for expanding aneurysm sacs with T2ELs after EVAR at an academic medical center between 2006 and 2017. The primary outcomes assessed were need for repeated intervention; intervention types; and achievement of clinical success, defined as stable aneurysm sac size on computed tomography angiography after treatment. ResultsFifty-six patients underwent 119 interventions, of which 107 (90%) were technically successful. The median time from EVAR to index T2EL procedure was 37 months (interquartile range, 17-56 months), and the median follow-up time from first T2EL procedure was 27 months (interquartile range, 10-51 months). The most common index procedure was transarterial lumbar embolization (64%), followed by transarterial inferior mesenteric artery (20%), transcaval (14%), and translumbar embolization (1.8%). Thirty-three (59%) patients required further procedures for persistent aneurysm sac expansion. For subsequent T2EL interventions, the most common endovascular procedure was transarterial lumbar embolization (21%), followed by transcaval (21%), translumbar (11%), and transarterial inferior mesenteric artery embolization (8.6%). Twelve patients (21%) were found to have loss of proximal or distal seal on subsequent imaging and required graft extensions to stabilize aneurysm sac size. Ten patients (18%) ultimately underwent graft explantation or sacotomy with oversewing of the endoleak source. Freedom from any endoleak-related reintervention was 57% at 1 year and 36% at 3 years. Freedom from open treatment was 93% at 1 year and 82% at 3 years. Of the 44 patients with ≥6-month follow-up, 39 (89%) achieved clinical success. However, only 11 patients (25%) achieved clinical success without any further reintervention, and 29 patients (66%) achieved clinical success without open treatment. ConclusionsDespite high technical success, endoleak recurrence after T2EL treatment is common, and multiple interventions are often needed to stabilize aneurysm sac size in patients diagnosed with T2EL-associated sac growth. Notably, one in five patients treated for T2ELs was discovered, on further evaluation, to have proximal or distal seal zone loss that necessitated repair to achieve sac stability. Thus, thorough assessment of all endoleak types should be performed in patients with T2ELs associated with sac growth before T2EL treatment to ensure appropriate care and to minimize ineffective interventions.

Value of Preliminary Selective Lumbar and Inferior Mesenteric Artery Embolization to Prevent Type II Endoleaks After Endovascular Aneurysm Repair

Preliminary selective lumbar artery (LA) and inferior mesenteric artery (IMA) embolization to prevent type II endoleaks (T2ELs) has not been widely evaluated. Our aim was to determine the rate of endoleak and size decrease of infrarenal abdominal aortic aneurysm after endovascular aneurysm repair (EVAR) after pre-emptive coil embolization of IMA and LA in patients at high risk for T2EL. Between September 2014 and September 2019, 139 of 244 patients (56.9%) who underwent EVAR for abdominal aortic aneurysm also underwent selective percutaneous embolization of the IMA and LA before or during EVAR because of risk factors for T2EL. The embolization was performed using either coils or vascular plugs to achieve occlusion of the target vessel confirmed on angiography. Computed tomography and contrast-enhanced ultrasound imaging were performed at 1 month and 6 months and yearly after the procedure to detect endoleaks and to assess the aneurysm sac diameter. Mean follow-up was 23 ± 16 months (range, 1-61 months). Patients had a median of five (range, one to eight) patent LAs and IMAs on preoperative imaging. After completion of embolization, 80% (range, 20%-100%) of direct arterial flow to the aneurysm sack was occluded, with no procedurally related complications. Follow-up imaging showed T2EL in seven patients (5 %). Increase of the aneurysm sac was seen in eight patients during follow-up, of whom two had type I endoleak and six had T2EL. Six T2EL-related interventions were performed during follow-up, of which only one was successful. Shrinkage of the aneurysm sac diameter was in mean 9.2 ± 7.7 mm, which was statistically significant (P < .001). Surgery was required in one patient for proximal type I endoleak. No aneurysm-related death occurred. Preliminary selective LA and IMA embolization for patients at risk for T2EL is safe and effective in preventing development of T2EL. This procedure is associated with rapid decrease in aneurysm sack size.

Laparoscopic Clipping of the Inferior Mesenteric Artery and Intraoperative Indocyanine Green Angiography for Type II Endoleak Following Endovascular Aneurysm Repair.

Background: Type II endoleaks from a patent inferior mesenteric artery (IMA) occur in up to one-third of patients undergoing endovascular repair of abdominal aortic aneurysms. In the majority of patients, retrograde flow in the aneurysmal sac outside the endograft will seal over time and is rarely associated with sac enlargement or aortic rupture. Intervention is generally recommended in patients with progressively enlarging endoleaks, especially when the sac diameter increases >10 mm during the follow-up, and endovascular IMA embolization has a high rate of treatment failure. Methods: We report a procedure of laparoscopic IMA clipping combined with intraoperative indocyanine green (ICG) angiography to confirm vascular anatomy, colonic perfusion, and the technical success of the procedure. Results: Three selected octogenarian patients with persistent type II endoleak after endovascular repair of abdominal aortic aneurysm underwent IMA clipping with ICG angiography. Mean operative time was 58 ± 9 minutes. There were no procedure-related complications, and no hypersensitivity reactions nor other side effects associated with ICG dye administration occurred. All patients were discharged home on postoperative day 1 and are asymptomatic and free of recurrence at a mean follow-up of 15 months. Conclusions: Laparoscopic IMA clipping is a safe remedial procedure in patients with type II endoleak after endovascular repair of abdominal aortic aneurysms.

Preoperative Inferior Mesenteric Artery Embolization Is a Cost-effective Technique That May Reduce the Rate of Aneurysm Sac Diameter Enlargement and Reintervention Following EVAR

Preoperative Inferior Mesenteric Artery Embolization Is a Cost-effective Technique That May Reduce the Rate of Aneurysm Sac Diameter Enlargement and Reintervention Following EVAR

Preoperative Inferior Mesenteric Artery Embolization is a Cost-effective Technique that May Reduce the Rate of Aneurysm Sac Diameter Enlargement and Reintervention After EVAR

Type II endoleaks are the most common complications after endovascular repair of abdominal aortic aneurysms (EVARs). Some studies have shown the benefit of preventive inferior mesenteric artery (IMA) embolization, but its efficacy and cost-effectiveness continue to be controversial. The aim of this study was to evaluate the efficacy of this procedure on the increase in aneurysmal sac diameter during follow-up. All consecutive patients who underwent the embolization of the IMA before EVAR in our center, between January 2014 and July 2016, were included. We retrospectively compared the diameter of the aortic aneurysm sac, the rate of endoleak and reinterventions, and the theoretical cost of management between these patients (group 2) and a historical cohort of patients treated for EVAR before January 2014 who did not undergo prior IMA embolization (group 1). Two hundred twenty-four patients were retrospectively analyzed. After exclusion, we compared a group of 37 embolized patients with a control group of 46 patients. The rate of enlargement in the aneurysmal sac diameter was significantly higher in the control group at 2 years (27.9% vs. 4.3%, P = 0.025). The type II endoleak rate at 2 years was significantly higher in the control group (53.1% vs. 18.2%, P = 0.012), as was the aneurysm-related reintervention rate (31.1% vs. 8.1%, P = 0.013). Multivariate analysis confirmed these results. At 2 years of follow-up, there was no difference in the overall cost of patient management between the 2 groups. Preventive IMA embolization is an effective, reliable, and cost-effective technique that seems to reduce the rate of the aneurysmal sac diameter enlargement, type II endoleak, and reinterventions after EVAR.

Inferior mesenteric artery embolization for persistent postpartum hemorrhage after sufficient bilateral iliac arteries embolization: safety and efficacy in eight patients.

To assess the safety and efficacy of transcatheter arterial embolization (TAE) of the inferior mesenteric artery (IMA) for the management of post-partum hemorrhage (PPH). A retrospective analysis was performed regarding eight patients (mean age, 34.4 y; age range, 31 - 40 y) who underwent TAE of the IMA for PPH between March 2001 and September 2018. Obstetric records, including maternal characteristics, clinical manifestations, complications, and clinical outcomes, as well as TAE details were obtained. All eight patients had primary PPH and the vaginal delivery mode. CT scans of two patients showed active bleeding from the lower uterus or hematoma and with the origin of contrast extravasation abutting the adjacent rectum. In seven patients, an aortogram or IMA arteriogram following persistent vaginal bleeding after sufficient embolization of the bleeding focus from the bilateral iliac arteries, found the bleeding focus of the IMA, while in one patient, the IMA bleeding focus was found at the second session 4 h after the first session. TAE of the IMA was technically successful in all eight patients and cessation of bleeding without repeated TAE or additional hemostatic surgery was achieved in all patients after TAE of the IMA. There were neither procedure-related complications nor bowel ischemia during follow-up. TAE of the IMA for PPH was safe and effective with successful hemostasis. Bleeding from the IMA should be suspected when there is persistent vaginal bleeding after sufficient embolization of bleeders from the bilateral iliac arteries. Bleeding from the IMA should be suspected when there is persistent vaginal bleeding after sufficient embolization of bleeders from the bilateral iliac arteries.

Pre-emptive nonselective perigraft aortic sac embolization with coils to prevent type II endoleak after endovascular aneurysm repair

ObjectivePre-emptive selective embolization of inferior mesenteric artery (IMA), lumbar arteries (LAs), and perigraft sac for prevention of type II endoleak (T2EL) has not been widely adopted. We perform pre-emptive nonselective perigraft aortic sac embolization with coils (PNPASEC) in patients at high risk for development of T2EL (four or more patent LAs, patent IMA ≥3 mm, and ≥30-mm aortic flow lumen). The goal of this study was to see whether PNPASEC decreases T2ELs requiring reinterventions. MethodsAll 266 patients undergoing elective endovascular aneurysm repair between September 1, 2007, and October 31, 2015, were retrospectively evaluated from a prospectively maintained database. Patients (N = 212; 211 men) with preoperative and postoperative contrast-enhanced computed tomography scans were included. Our PNPASEC technique involves leaving a wire in the sac after cannulation of the contralateral gate and inserting large (0.035-inch) coils into the sac after bifurcated graft deployment. T2EL and reintervention rates were compared between patients who underwent PNPASEC (group I) and those who met the criteria but did not have PNPASEC (group II) and those who did not meet the criteria (Group III). ResultsForty-seven (22.2%) patients were PNPASEC candidates and 165 (77.8%) patients (group III) were not. Among PNPASEC candidates, 16 (7.5%) underwent PNPASEC (group I) and 31 (14.6%) did not (group II). There were no significant differences between groups in terms of comorbidities, aneurysm size, and anatomic and neck characteristics. Mean number of patent LAs was similar between group I (4.5 ± 0.8) and group II (4.5 ± 0.9), which was significantly greater than in group III (1.9 ± 1.3; P < .001); 43.6% of group III patients had patent IMA. Mean follow-up was 44 ± 25 months. T2EL at 6 months was observed in 48.4% in group II, 3.0% in group III, and 6.3% in group I (P < .001). Sac diameter increase was seen in 38.7% in group II vs 6.1% in group III and 6.3% in group I (P < .001), with complete sac shrinkage in 23.3% in group II vs 23.8% in group III and 50.0% in group I (P = .09). T2EL-related interventions were performed in 29.0% in group II vs 1.2% in group III and 6.3% in group I (P < .001). Any endoleak at last follow-up was seen in 25.8% in group II vs 2.4% in group III and none in group I (P < .001). ConclusionsNonselective perigraft sac coil embolization in patients at high risk for T2EL (20% of patients undergoing endovascular aneurysm repair) is effective in preventing development of T2EL and is associated with decrease in sac size and reintervention rates.