Midterm Outcomes of Endovascular Abdominal Aortic Aneurysm Repair with Prevention of type 2 Endoleak by Intraoperative Aortic Side Branch Coil Embolization.

OBJECTIVE: The midterm results of endovascular abdominal aortic aneurysm repair (EVAR) with aortic side branch coil embolization during EVAR was evaluated. METHODS: Our center began coil embolization for all patent inferior mesenteric artery (IMA) and lumbar artery (LA) with an inner diameter more than 2.0 mm during EVAR since June 2015. When four or more LA were patent, coil embolization for LA with inner diameter 2.0 mm or less was done. EVAR without aortic side branches coil embolization was performed for 59 patients prior to June 2015 (control group) and 79 patients underwent EVAR with coil embolization during EVAR (coil group). The success rate of coil embolization for IMA and LA was evaluated in coil group. The frequency of type 2 endoleak (T2EL), freedom from aneurysm sac expansion (5 mm or more) rate and the rate of the aneurysm sac shrinkage (10 mm or more) were compared between the coil and control groups. Additionally, multiple logistic regression analysis for all patients was conducted to analyze whether IMA patency and the number of patent lumbar artery at the end of EVAR were the risk factors of the aneurysm sac expansion of 5 mm or more. RESULTS: The success rate of IMA coil embolization was 96.4% and that of LA was 74.5%. Compared to the control group, the frequency of T2EL was significantly lower in coil group at 7 days (1.3% vs. 60.4%, P <0.0001) and at 6 months (2.1% vs 38.2%, P <0.0001) after EVAR. The freedom from aneurysm sac expansion rate was significantly better in the coil group at 5 years (100% in coil group and 65.2% in control group, P = 0.002). The rate of aneurysm sac shrinkage was significantly better in coil group (15.5% vs. 2.0% at 1 year, 42.8% vs. 6.3% at 2 years and 53.4% vs. 17.8% at 3 years, p = 0.0007). The risk of aneurysm sac expansion of 5 mm or more was estimated to be 11 times greater when the IMA was patent, and 4.9 times greater when 3 or more LAs were patent at the end of EVAR. CONCLUSION: When IMA was occluded and the number of patent LA became 2 or less by aortic side branch coil embolization during EVAR, favorable mid-term results were safely obtained and good long-term result could be expected with EVAR.

Primary Conservative Therapy for Symptomatic Isolated Mesenteric Artery Dissection with Severely Compressed True Lumen or Large Dissecting Aneurysm.

PURPOSE: To investigate the safety and effectiveness of primary conservative therapy for patients with symptomatic isolated mesenteric artery dissection (IMAD) with a severely compressed true lumen and/or a large dissecting aneurysm. MATERIALS AND METHODS: A total of 35 consecutive patients (all men; median age, 53 y) with symptomatic IMAD with a severely compressed true lumen and/or a large dissecting aneurysm but without intestinal necrosis or arterial rupture who were treated with primary conservative therapy between November 2018 and February 2020 were assessed. A severely compressed true lumen was defined as luminal stenosis > 70%. A large dissecting aneurysm was defined as dissecting aneurysm diameter ≥ 1.5 times larger than the normal mesenteric artery diameter. RESULTS: There was a strong positive relationship among abdominal pain, degree of luminal stenosis, and length of dissection (R = 0.811; P < .001). Conservative treatment was successful in all patients. Abdominal pain was eliminated within 4.7 d ± 4.8 (range, 2-31 d) in all patients, within 3.6 d ± 1.2 (range, 2-6) in the 31 patients with minor or moderate abdominal pain, and within 13.3 d ± 11.9 (range, 6-31 d) in the 4 patients with severe abdominal pain. Complete or partial remodeling of the mesenteric artery was achieved in 6 (17.1%) and 29 (82.9%) patients, respectively, during 8.6 mo ± 4.3 of follow-up. CONCLUSIONS: Primary conservative therapy can be used safely and effectively in patients with symptomatic IMAD with a severely compressed true lumen and/or a large dissecting aneurysm but without intestinal necrosis or arterial rupture.

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

BACKGROUND: Although the preoperative risk factors associated with the occurrence of type II endoleak (ETII) after endovascular aortic repair (EVAR) have gradually become more evident, the preoperative risk factors associated with aneurysm sac enlargement caused by ETII remain unclear. This study aimed to determine the preoperative risk factors associated with aneurysm sac enlargement caused by ETII after EVAR. METHODS: This retrospective cohort study reviewed 519 EVARs performed for true abdominal aortic aneurysm between January 2006 and December 2018 at our institution. EVARs using commercially available bifurcated devices with no type I or III endoleaks during follow-up and with ≥12 months follow-up were included. A total of 320 patients were enrolled in the study. To identify the preoperative risk factors of sac enlargement after EVAR, Cox regression analysis was used to assess preoperative data. RESULTS: The median follow-up period was 60.8 months. Overall, 135 of 320 patients (42%) had ETII during follow-up, and 47 of 135 patients (35%) developed aneurysm sac enlargement. Multivariate analysis revealed that chronic kidney disease (CKD) stage ≥4 (hazard ratio [HR], 4.65; 95% confidence interval [CI], 2.13-10.15; P = 0.001), patent inferior mesenteric artery (IMA) (HR, 17.85; 95% CI, 2.46-129.73; P< 0.001), and number of patent lumbar arteries (LAs) (HR, 1.37; 95% CI, 1.13-1.68; P= 0.002) were risk factors of aneurysm sac enlargement caused by ETII. CONCLUSIONS: CKD stage ≥4, patent IMA, and number of patent LAs were independent risk factors for aneurysm sac enlargement after EVAR. In particular, patent IMA had the highest HR and seemed to have the greatest impact on long-term aneurysm sac enlargement. Hence, taking preoperative measures to address a patent IMA appears to be important in reducing the incidence of sac enlargement.

Outcomes Following Inferior Mesenteric Artery Reimplantation During Elective Aortic Aneurysm Surgery.

BACKGROUND: The role of inferior mesenteric artery (IMA) reimplantation during open aortic reconstruction is debated. We assessed outcomes after inferior mesenteric artery reimplantation (IMAR) for aortic aneurysmal disease to help shed light on this question. METHODS: A single-center retrospective review of all IMARs performed during open aortic surgery over a 10-year period between 2000 and 2009 was carried out. The primary outcome was patency, while secondary outcomes included colonic ischemia and overall survival. Analysis was performed using Cox models and Kaplan-Meier estimates. RESULTS: Of 840 patients who underwent elective abdominal aortic aneurysm (AAA) reconstructions during this period, 70 underwent IMAR. Indications for IMAR included intraoperative colonic ischemia (n = 24), poor back bleeding (n = 52), large IMA (n = 5), internal iliac disease (n = 5), and prior colon surgery (n = 1). Follow-up imaging studies were available in 35 of 70 patients (computed tomography in 30 [86%] and duplex in 5 [14%]). Patency was confirmed in 32 of 35 patients (91%) over a median follow-up of 98 months. Both losses in patency were at 4 months and did not require an operation. One patient underwent left colon resection on postoperative day 9 because of ischemia. (Patency could not be confirmed.) No statistically significant predictor of patency was noted. Incidence of colonic ischemia was 1.4% in patients undergoing IMAR. The overall mortality was 51% in patients undergoing IMAR over the median follow-up period. The overall 10-year survival was 30% in patients undergoing IMAR for aortic aneurysmal disease. The nature of aneurysm (juxtarenal or higher juxta renal abdominal aortic aneurysm [JRAAA]) was associated with mortality, with a hazard ratio of 1.8 (P = 0.08) approaching significance. Ten-year survival was worse if IMAR was performed for intraoperative colonic ischemia (26% vs 34%) or in JRAAA (19.0% vs 38%; P = 0.03). Age per year at the time of repair was the only statistically significant predictor of survival (P < 0.001). CONCLUSION: IMAR for AAA remains necessary for select patients. Reimplantation is associated with excellent long-term patency and low risk of colonic ischemia.

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

OBJECTIVE: Pre-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. METHODS: All 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). RESULTS: Forty-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). CONCLUSIONS: Nonselective 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.

The role of the inferior mesenteric artery in predicting secondary intervention for type II endoleak following endovascular aneurysm repair.

OBJECTIVE: Endovascular aneurysm repair (EVAR) is associated with a greater risk of graft-related complications and need for secondary interventions compared with open repair. Type II endoleak (EL-2) is the most common complication. We examined the hypothesis that a functionally occluded inferior mesenteric artery (IMA) before EVAR was associated with fewer secondary interventions for EL-2. METHODS: All nonruptured abdominal aortic aneurysms (AAA) treated by EVAR using U.S. Food and Drug Administration-approved endografts from January 2005 to December 2017 were retrospectively reviewed, including computed tomography angiograms. Preoperative patency of the IMA and any secondary interventions performed after the index EVAR procedure were recorded. A functionally occluded IMA was defined as one that was (1) chronically occluded or severely stenosed on preoperative imaging or (2) coil embolized before EVAR. Secondary interventions for persistent EL-2 were indicated when AAA sac diameter increased by more than 5 mm. RESULTS: The study cohort comprised 490 patients (84 women) with a mean age of 74.8 ± 8.2 years. The mean preoperative AAA diameter was 5.6 ± 0.9 cm. One hundred twenty-nine patients (26.3%) died during follow-up. The mean follow-up of survivors was 38 months. Types (prevalence) of endoleak were I (2.4%), II (18.9%), III (0.7%), IV (0.5%), and V (0.2%). Patients with a functionally occluded IMA underwent significantly fewer secondary interventions for EL-2 compared with patients with a patent IMA (2.6% vs 7.1%; P = .020). All secondary interventions in the functionally occluded IMA group involved the lumbar arteries (LA). When the IMA was patent, secondary interventions were equally distributed between the LA and IMA. Logistic regression confirmed that a functionally patent IMA was associated with a greater number of secondary interventions for EL-2 (odds ratio, 3.0; 95% confidence interval, 1.2-7.5; P = .025). CONCLUSIONS: Patients with a functionally occluded IMA required significantly fewer secondary interventions for EL-2 after EVAR. In addition, the type of vessels intervened on were primarily LA. Among patients with a patent IMA, preoperative coil embolization may decrease secondary interventions and improve the long-term durability of 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.

BACKGROUND: 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. MATERIALS AND METHODS: 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). RESULTS: 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. CONCLUSIONS: 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.

"Aortoiliac-Mesenteric Steal Syndrome" Treated with Inferior Mesenteric to Common Iliac Artery Transposition.

We report the case of a 54-year-old female who presented with chronic mesenteric ischemia symptoms which could also be provoked on walking 50-100 m. Computed tomography angiography demonstrated ostial occlusion of all 3 mesenteric vessels, with extensive collateralization reconstituting the inferior mesenteric artery from the iliac arteries. As such, her abdominal pain was secondary to preferential flow to the lower limbs stealing from mesenteric vasculature. Endovascular management was trialed, but failed after short-term improvement, so the patient underwent successful transposition of inferior mesenteric to left common iliac artery. Mesenteric ischemia presenting with pain on walking secondary to preferential flow to the lower limbs has not been previously reported, and vascular and general surgeons should be aware of this unusual differential for abdominal pain.

Identification of Anatomical Risk Factors for Type II Endoleak to Guide Selective Inferior Mesenteric Artery Embolization.

BACKGROUND: It is unclear which patients are the best candidates for inferior mesenteric artery (IMA) embolization to reduce type II endoleak (ELII). Therefore, this study aimed to identify the anatomical risk factors for ELII after endovascular aneurysm repair (EVAR) and to determine the best candidates for preventative, preoperative IMA embolization. MATERIALS AND METHODS: Between April 2007 and September 2014, 196 patients underwent standard EVAR. Anatomical risk factors of postoperative, persistent ELII were detected using logistic regression analysis. Preoperative treatment of the IMA occlusion in patients with anatomical risk factors was performed to reduce ELII. RESULTS: ELII was detected in 48 patients (24.5%). Overall, patency of the IMA (odds ratio [OR], 4.13; P = 0.004) and lumbar artery (LA) diameter ≥2.0 mm (OR, 3.30; P = 0.008) were significant risk factors for ELII, whereas an Endurant stent graft protected against ELII (OR, 0.22; P = 0.023). However, in patients with patent IMA, IMA diameter ≥3.0 mm (OR, 4.09; P = 0.011), LA diameter ≥2.0 mm (OR, 3.16; P = 0.043), and aortoiliac aneurysm (OR, 6.36; P = 0.026) were significant risk factors for ELII. Incidence rates of ELII in patients with and without these factors were 37.8% and 11.2%, respectively. ELII did not occur in patients with risk factors who underwent treatment of preoperative IMA occlusion. CONCLUSIONS: Patients with these risk factors are the candidates for undergoing treatment of preoperative IMA occlusion to reduce ELII.

"Mesenteric Steal" Physiology as a Cause of Claudication and Chronic Mesenteric Ischemia.

Aortoiliac occlusive disease results in varying degrees of pelvic and lower extremity arterial insufficiency. Treatment approach has evolved, and endovascular therapies are being successfully reported for high-grade lesions. However, Trans Atlantic Inter-Society Consensus D often necessitates open revascularization. Disease limited to the infrarenal segment does not typically affect intestinal perfusion in the absence of visceral aortic or mesenteric vessel involvement. Chronic mesenteric ischemia most commonly occurs due to atherosclerotic disease of 2 or 3 of the mesenteric vessels. The marginal artery of Drummond is an important component of the collateral network that allows for continued intestinal perfusion. We report a case of short-segment subtotal infrarenal aortic occlusion, proximal to the inferior mesenteric artery (IMA) in the absence of significant mesenteric disease. The patient had resultant lifestyle limiting claudication and chronic mesenteric ischemia. Angiographic evaluation demonstrated "mesenteric steal" physiology with retrograde flow via the arc of Riolan and IMA to perfuse the aortoiliac circulation. Successful endovascular recanalization with a balloon-expandable covered stent was achieved, resolving the arterial insufficiency in both the mesenteric and lower extremity vascular beds. The patient denied any symptoms on postoperative day 1 and at 1-month follow-up.

Systematic review of laparoscopic ligation of inferior mesenteric artery for the treatment of type II endoleak after endovascular aortic aneurysm repair.

OBJECTIVE: Type II endoleak after endovascular aneurysm repair (EVAR) is frequently caused by persistent flow from the inferior mesenteric artery (IMA). The aim of this study was to assess the perioperative and midterm efficacy of laparoscopic ligation of the IMA for treatment of endoleak. METHODS: MEDLINE, Cochrane Central Register of Controlled Trials, and Cochrane databases and key references were searched with Preferred Reporting Items for Systematic Reviews and Meta-Analyses methodology for studies reporting on laparoscopic ligation of the IMA for treatment of type II endoleak after EVAR. RESULTS: Eight case studies and one study of a retrospective nature were identified. In total, 20 patients (18 men; mean age, 73.6 ± 2 years; with a mean abdominal aortic aneurysm diameter of 64.3 ± 10 mm) who underwent post-EVAR laparoscopic ligation of the IMA for type II endoleak were analyzed. The mean time from EVAR until intervention ranged from 6 to 18 months. All but one patient were asymptomatic; in 9, the aneurysm sac was enlarged, and in 11, the endoleak was considered persistent without sac enlargement. The mean procedural duration was 99 ± 24 minutes, with technical success rate of 90% (18/20); in two cases, the patients were successfully reoperated on laparoscopically in 24 hours. The mean hospitalization was 3.6 ± 1.2 days, with 0% (0/20) perioperative and 30-day mortality. No patient underwent open conversion or showed signs of intestinal ischemia. During follow-up of 32.6 ± 12 months, 13 of 20 patients had aneurysm sac regression, whereas the rest had a stable sac diameter without evidence of persistent type II endoleak. CONCLUSIONS: Laparoscopic ligation of the IMA for treatment of type II endoleak after EVAR is a feasible and safe technique in specialized centers with high technical success rate and good midterm outcomes.

Definition of Type II Endoleak Risk Based on Preoperative Anatomical Characteristics.

PURPOSE: To define the risk for type II endoleak (EII) after endovascular aneurysm repair (EVAR) based on preoperative anatomical characteristics. METHODS: Between January 2008 and December 2015, 189 patients (mean age 78.4±7.6 years; 165 men) underwent standard EVAR. Mean aneurysm diameter was 5.7±0.7 cm and mean volume 125.2±45.8 cm3. Patients were assigned to the "at-risk" group (n=123, 65%) when at least one of the following criteria was present: patency of a >3-mm inferior mesenteric artery (IMA), patency of at least 3 pairs of lumbar arteries, or patency of 2 pairs of lumbar arteries and a sacral artery or accessory renal artery or any diameter patent IMA; otherwise, patients were entered in the "low-risk" group (n=66, 35%). EII rates and freedom from EII reintervention were compared using Kaplan-Meier curves. Preoperative clinical and anatomical characteristics were evaluated for their association with EII and EII reinterventions using multiple logistic regression analysis; results are presented as the odds ratio (OR) and 95% confidence interval (CI). RESULTS: Freedom from endoleak was lower in the at-risk group compared with the low-risk group at 36 months after EVAR (p=0.04). Freedom from EII-related reinterventions was significantly lower in the at-risk group (80% vs 100%, p=0.001) at 48 months. Based on the multiple regression analysis, the at-risk group had a higher likelihood of both EII (OR 9.91, 95% CI 2.92 to 33.72, p<0.001) and EII-related reinterventions (OR 9.11, 95% CI 1.06 to 78.44, p=0.04). These criteria had 89.4% (95% CI 83.9% to 93.2%) sensitivity and 48.0% (95% CI 40.7% to 55.3%) specificity for EII; sensitivity and specificity for EII reintervention were 100% (95% CI 93.8% to 100%) and 38.8% (95% CI 31.9% to 46.2%). Within the at-risk group, a sac thrombus volume <35% was an additional predictor for both EII (OR 5.21, 95% CI 1.75 to 15.47, p=0.003) and EII-related reinterventions (OR 8.33, 95% CI 2.20 to 31.51, p<0.002). CONCLUSION: The selection criteria effectively discriminated between low-risk patients and patients at risk for EII and associated reinterventions. A thrombus volume <35% was an additional predictor for EII and EII-related reintervention among patients at risk. These criteria may be useful for preemptively selecting patients who may benefit from EII prevention procedures or a more aggressive surveillance protocol.

Innovative Procedure for Inferior Mesenteric Artery Embolization Using the Amplatzer Vascular Plug 4 during Endovascular Aneurysm Repair.

PURPOSE: The aim of this study is to present an easy and quick technique for embolization of the inferior mesenteric artery (IMA) during endovascular aneurysm repair (EVAR). TECHNIQUE: We performed IMA embolization using a conventional EVAR device alone with the femoral artery approach during EVAR, which has not been reported previously. First, a 16F or 18F DrySeal Sheath is inserted from the femoral artery into the site around the IMA. Second, cannulation is performed in the IMA with an angiography catheter having a 0.038-inch inner lumen that is used for gate cannulation during EVAR. Third, IMA embolization is performed using the Amplatzer Vascular Plug 4 (AVP4). The use of the DrySeal Sheath facilitates cannulation of the IMA, and its combination with a stent-graft balloon allows the AVP4 to be placed at the root of the IMA without deviation of the catheter. The success rate of the procedure was 90.9% (30/33 cases). The median procedure time was 11.6 min. No complications due to IMA embolization were noted. CONCLUSION: This procedure enables safe and quick placement of the AVP4 in the IMA using the catheter insertion approach from the femoral artery, which has been conventionally regarded as difficult.

Chimney Stent-Graft Repair for Concurrent Inferior Mesenteric Artery Aneurysm and Infrarenal Abdominal Aortic Aneurysm: Case Report.

PURPOSE: To report a rare case of concurrent inferior mesenteric artery (IMA) aneurysm and infrarenal abdominal aortic aneurysm (AAA) with a novel indication for the use of chimney stent-graft technique in this patient. CASE REPORT: An 82-year-old man with an asymptomatic 4.4-cm fusiform AAA and 3.6-cm IMA aneurysm, coupled with chronic occlusion of celiac artery and superior mesenteric artery at the ostia, underwent endovascular repair of both aneurysms. Preservation of the IMA and treatment of both aneurysms were achieved with IMA aneurysm stenting, aortic aneurysm stenting and IMA chimney stenting. At 1, 6, and 12 months surveillance, the grafts remained patent without endoleak. CONCLUSIONS: The IMA chimney with aortic stenting technique may be safely used in patients who require preservation of the IMA during AAA and IMA aneurysm repairs.

Role of type II endoleak in sac regression after endovascular repair of infrarenal abdominal aortic aneurysms.

OBJECTIVE: Endovascular repair (EVAR) of infrarenal aortic aneurysms (AAA) is increasingly used in patients with suitable aortic morphology conforming to device-specific instructions for use. Despite improvements in graft design, type II endoleak (EL-2) from the inferior mesenteric artery (EL-IMA) or the lumbar artery (EL-LA) remains the Achilles' heel of EVAR. The objective of this study was to evaluate the natural history of the AAA sac after EVAR. We hypothesized that persistent EL-2 would be associated with inferior AAA sac volume regression. METHODS: A retrospective analysis was performed on all nonruptured AAA treated by elective EVAR using Food and Drug Administration-approved endografts from January 2005 to December 2008 in our facility. Review of medical records and preoperative and follow-up computed tomography angiograms at 1, 6, and 12 months was performed. Patients with type I, III, and IV endoleaks were excluded, as were those lost to all follow-up. AAA size and volume were analyzed using TeraRecon software (Aquarius Intuition, Foster City, Calif). Change in AAA sac volume was compared in patients with and without EL-2, and with an occluded vs patent IMA. RESULTS: The study cohort comprised 191 patients (161 men, 30 women) with a mean age of 74 years. The mean preoperative AAA diameter was 5.5 cm (range, 4-11 cm), and mean volume was 137.45 cm(3). EL-2 was present in 24% at completion of EVAR and in 9% at a mean follow-up of 6 months (range 4-8 months). Completion angiography at 1 month showed 63% of EL-2 had resolved. Those with EL-2 present at 1 month had statistically inferior sac regression compared with those who did not (23% reduction vs 2% increase at 1 year; P = .002). Preoperatively, the IMA was occluded by coils or was chronically occluded in 82 patients vs 109 patients who had a patent IMA. At the 6-month follow-up, patients with an occluded IMA had an EL-2 rate of 2.4% vs 14.7% in those with a patent IMA (P = .005 by t-test). Sac volume regression was 21.8% in those with an occluded IMA vs 13.2% in those with a patent IMA (P = .004 by t-test). Regression in AAA sac volume was highly significant in patients with occluded IMA, at 30% vs 16% at 1 year (P = .0018 by two-sided t-test). CONCLUSIONS: The presence of persistent EL-2 after EVAR results in inferior AAA sac regression. A preoperatively patent IMA is associated with increased rates of EL-2 and inferior AAA sac regression. Consideration should be given to preoperative occlusion of a patent IMA before EVAR.

Characterizations of the α1-adrenoceptor subtypes mediating contractions of the human internal anal sphincter.

Human internal anal sphincter (IAS) is contracted by α1-adrenoceptor stimulation and thus α1-adrenoceptor agonists may be useful in treating fecal incontinence. This study characterizes the contribution of α1-adrenoceptor subtypes in contraction of human IAS and to investigate the age-related risk of patients with fecal incontinence. IAS and inferior mesenteric artery (IMA), as a predictor of systemic arterial pressure, were obtained from 11 patients. Both muscle strips were assessed by isometric-contraction experiments using phenylephrine, further in IAS, in the presence of various subtype selective α1-adrenoceptor antagonists. Immunohistochemistry and gene expression studies were performed in the same samples. The mean pEC50 values with SEM of phenylephrine in IAS (6.30 ± 0.13) were higher than those of IMA (5.60 ± 0.10). Furthermore, the age-related pEC50 change of IAS was observed between age <70 and ≥70 (6.58 ± 0.13 and 6.07 ± 0.16, respectively (P < 0.05)). In IAS, rightward shift of the concentration-response curves of phenylephrine was observed with three α1-adrenoceptor antagonists. Each pKB value of silodosin, BMY-7378 and prazosin was 9.36 ± 0.53, 7.28 ± 0.20 and 8.89 ± 0.12, respectively. These pKB values and gene expression studies indicated that α1A-adrenoceptor subtypes predominantly contributed to human IAS contraction.

Inferior mesenteric to renal artery transposition for revascularization of a solitary functioning kidney.

The aim of this article is to describe a new open surgical technique for revascularization of renal arteries. Several interventions for surgical revascularization of renal arteries have been proposed. We suggest to perform an alternative technique if the described inflow vessels are not suitable because of severe atherosclerosis or calcifications. A 76-year-old woman with a solitary functioning kidney and a subocclusive renal artery stenosis presented at our institution with renovascular hypertension and chronic kidney disease. After a failed percutaneous renal angioplasty attempt, we successfully treated the patient with an end-to-end inferior mesenteric to renal artery transposition. Other described techniques for revascularization of renal arteries were not suitable in this case, as commonly used inflow vessels were severely calcified. Although further studies are needed to better investigate the safety and effectiveness, this technique is simple and affordable, and it could be considered a valid alternative approach in selected patients, if other proposed interventions are not feasible. To the best of our knowledge, this is the first reported case with this kind of surgical reconstruction.

Postpartum Uterine Bleeding from the Inferior Mesenteric Artery: Case Report and Review of the Literature.

Postpartum hemorrhage (PPH) is the leading cause of maternal mortality worldwide. The common causes of primary PPH include uterine atony, abnormal placentation, retained placenta, and birth canal injury. The inferior mesenteric artery (IMA) arises from the aorta and is the main artery to supply the descending and sigmoid colon, as well as the rectum. We present a case of immediate, severe uterine bleeding after a normal vaginal delivery; angiography determined that hemorrhage originated from the IMA, and there were no anastomoses between the IMA and other pelvic arteries. The patient was successfully managed by selective embolization of a distal branch of the IMA. Our case report presents a new and interesting variation of pelvic vascular anatomy; moreover, it is the first report to present a case of postpartum uterine bleeding originating from the IMA.

Complicated type B aortic dissection causing ischemia in the celiac and inferior mesenteric artery distribution despite patent superior mesenteric artery bypass.

Mortality rates associated with acute type B aortic dissection (ABAD) complicated by malperfusion remains significant. Optimal management of patients with ABAD is still debatable. We present a case report of a 50-year-old man who was admitted due to ABAD. He was treated medically with his pain resolved and he was discharged on oral antihypertensive medications. One month after initial diagnosis, he was readmitted with abdominal pain, nausea, vomiting, and diarrhea. On imaging, an extension of the aortic dissection into the visceral arteries with occlusion of the celiac and superior mesenteric arteries (SMA) was noted. He underwent thoracic endovascular aortic repair (TEVAR) and bypass grafting to the SMA. Despite the intervention, the patient developed large bowel, liver, and gastric ischemia and underwent bowel resection. He died from multi-organ failure. In selected cases of uncomplicated ABAD, TEVAR should be considered and when TEVAR fails and visceral malperfusion develops, an aggressive revascularization of multiple visceral arteries should be attempted.