Significant Endoleak Research Articles

Predicting Features of Visceral Stent Failure in Fenestrated Endovascular Aortic Aneurysm Repair.

Visceral stents in fenestrated endovascular aortic repair (FEVAR) have a significant risk of complications and carry a considerable burden of reinterventions. The aim of this study is to identify preoperative and intraoperative predictors of visceral stent failure. A retrospective review of 75 consecutive FEVARs in a single center from 2013 to 2021 was undertaken. Data on mortality, stent failure, and reintervention pertaining to 226 visceral stents were collected. Anatomical features including aortic neck angulation, aneurysm diameter, and angulation of target viscerals were obtained from preoperative computed tomography (CT) scans. Stent oversizing and intraprocedural complications were recorded. Postoperative CT scans were analyzed to determine the length of cover of target vessels. Only bridging stents through fenestrations to visceral vessels were considered; 28 (37%) cases had 4 visceral stents, 24 (32%) had 3, 19 (25%) had 2, 4 (5%) had 1. Thirty day mortality was 8%, a third of which was related to visceral stent complications. Intraprocedural complexity was documented during the cannulation of 8 (3.5%) target vessels, with a technical success rate of 98.7%. A significant endoleak or visceral stent failure was identified in 22 stents (9.8%) postoperatively, of which 7 (3%) had in-patient reintervention within 30 days. Further reinterventions at 1, 2, and 3 years were 12 (5.4%), 2 (1%), and 1 (0.4%), respectively. Most reinterventions were for renal stents (n=19, 86%). A smaller stent diameter and a shorter length of visceral stent were significant predictors of failure. No other anatomical feature or stent choice was found to be a significant predictor of failure. The modality of visceral stent failures varies, but renal stents with a smaller diameter and/or shorter length are more likely to fail over time. Their complications and reinterventions are common and carry a significant burden; therefore, close surveillance must be continued long term. With this work we share the methodology adopted at our centre to treat juxtarenal aneurysm with FEVAR. Thanks to this detailed review of anatomical and technical features we provide guidance for endovascular surgeons to face hostile aneurysm with peculiar visceral vessels anatomy. With our findings will also motivate industries in their attempt to produce improved technologies able to overcome issues identified in this paper.

Elastic Deformation Measurement Using Duplex Ultrasound for the Detection of High Aneurysm Sac Pressure Following EVAR.

To describe the concept of aortic elastic deformation (ED) measurement using duplex ultrasonography (DUS) as a tool for detection of high aneurysm sac pressure following endovascular aortic repair (EVAR). High aneurysm sac pressure, with or without proven endoleak, will result in a less compressible aneurysm. Using the dual image function in B-mode of the DUS device and a standardized amount of applied probe pressure, ED can be measured. It is defined as the percentage of deformation of the aneurysm sac on probe pressure application. We hypothesize that less ED of the aneurysm sac can be related with high aneurysm sac pressure and possibly the presence of clinically relevant endoleak. In this note, we describe the technical details of the procedure and report on the applicability and results of ED measurements in the framework of aortic aneurysm and EVAR follow-up in a cohort of 109 patients. ED measurement is the first noninvasive pressure-based method in the quest to find a practical and reliable diagnostic tool to exclude high aneurysm sac pressure. In our patient cohort, patients with proven endoleak showed a smaller ED (less compressible), implying the presence of high aneurysm sac pressure. Further research should confirm whether ED measurement using DUS could reliably exclude endoleak after EVAR and further explore its potential for clinical application in EVAR follow-up. For the first time, a simple, fast, and inexpensive diagnostic tool is presented in this study for detecting high sac pressure following EVAR. High sac pressure is typically caused by clinically significant endoleaks, which can have significant consequences. Currently, computed tomography scanning is the most common method used to identify and characterize endoleaks. However, measuring elastic deformation may potentially replace more invasive and expensive modalities, such as the computed tomography in the future.

Pseudoendoleak: A post-endovascular aortic repair ultrasound surveillance pitfall - Single institution case series.

In the context of increasingly common endovascular treatment for abdominal aortic aneurysms, endoleak is a relatively common complication of (abdominal) EVAR, and ongoing multimodality surveillance programs are recommended by expert bodies including the Society for Vascular Surgery (SVS). We describe the colour doppler ultrasound (CDUS) finding defined as pseudoendoleak that may be misinterpreted as significant endoleak and may be resolved through the use of contrast-enhanced ultrasound (CEUS). Retrospective review of cases at our institution identified five cases where apparent endoleak on CDUS was not evident on CEUS, performed immediately following CDUS. Each of these five cases demonstrated interval increase in sac size at varying intervals post-EVAR, and in 4 out of 5 cases, no endoleak was demonstrated on multiple other modalities, at multiple time points. One case demonstrated an isolated type 2 endoleak at one time point, a finding that could not be reproduced. In each case, index-positive CDUS is thought to represent agitated fluid within the excluded sac that is not in continuity with the arterial blood pool as evidenced by the absence of CEUS enhancement. In cases of positive post-EVAR CDUS, CEUS is an effective tool to exclude the presence of pseudoendoleak and thus avoid further and potentially invasive diagnostic modalities in an elderly and comorbid cohort.

Prophylactic Aneurysm Embolization during EVAR Is Safe, Improves Sac Regression and Decreases the Incidence of Type II Endoleak

Clinically significant endoleaks remain costly, time-consuming, morbid and even mortal following endovascular aneurysm repair (EVAR). Perigraft arterial sac embolization (PASE) has been utilized to treat type II endoleaks (T2EL) diagnosed at the time of EVAR or after repair. Our objective was to analyze the safety and efficacy of prophylactic PASE on the incidence of T2EL and aneurysm sac regression in patients undergoing EVAR. We performed a retrospective review of prospectively maintained databases from the University of California San Diego and the San Diego Veterans Affairs hospitals between 2015 and 2019. Prophylactic PASE (pPASE) was performed at the time of EVAR with thrombin, contrast and gelfoam liquid embolic aneurysm treatment as previously described. We evaluated technical success, freedom from T2EL, freedom from reintervention, from sac expansion, from type I/III EL, from all-cause mortality (ACM), from aneurysm-related mortality and from non-target embolization (NTE). A total of 44 patients were included in the study. Technical success was 100% and no NTE was observed. The average duration of follow-up was 14±11months. In those treated and followed by CT scan, 100% of patients' aneurysms halted their growth following PASE, while 65.9% demonstrated sac regression. Mean aneurysm sac diameter decreased by 9mm (95% CI 7-12). At 3 years, freedom from T2EL was 87.1%. Presence of T2EL did not result in aneurysm expansion during the follow-up period and thus did not require reintervention in any of these patients. Freedom from re-intervention was 83.2% for Type Ib EL and limb occlusion and all procedures were determined to be successful at the time of completion. No aneurysm-related deaths occurred during the follow-up. PASE proves to be an effective tool in sac management for prophylaxis of endoleak and maximizing sac regression in EVAR. It is safe, effective and durable when employed in this manner in the short and medium-term and was associated with low rates of T2ELs and reinterventions and a 100% freedom from sac expansion. Further analysis is required to evaluate the long-term outcomes of this adjunctive procedure in EVAR.

Midterm evaluation of perigraft arterial sac embolization in endovascular aneurysm repair

ObjectiveManagement of clinically significant endoleaks (ELs) remains costly, time-consuming, and morbid. Unresolved ELs can result in rupture and mortality after endovascular aneurysm repair (EVAR). Perigraft arterial sac embolization (PASE) has been used to treat ELs diagnosed at the time of EVAR or during surveillance. MethodsA retrospective review of prospectively maintained databases was conducted. The databases were compiled from two institutions between 2006 and 2016. PASE was performed for type I, type II, or type III EL with a thrombin, contrast medium, and Gelfoam (Pfizer, New York, NY) slurry prepared as previously described. PASE was administered either at the time of EVAR (primary) or during surveillance (secondary). Safety end points included nontarget embolization, defined as neurologic or enteric clinical sequelae from lumbar artery or visceral artery embolization, allergic reaction, peripheral embolization, or rupture. Efficacy end points included successful resolution of EL and cessation of aneurysm sac growth on computed tomography (CT) scans with contrast enhancement. ResultsA total of 66 patients included in the study were treated with PASE. Primary PASE was performed in 38 patients (58%) and secondary in 28 (42%). Within the total cohort, the average clinical and CT scan follow-up was 1.7 years (0.1-11.6 years). Four patients required open repair for residual high-pressure ELs (one type IIIB and three type I; 6%). Of the 95% of patients who did not require open conversion, aneurysm growth did not occur during the follow-up period. In the overall cohort, PASE was successful in 88% of type I EL and 73% of patients with type II EL. There was no evidence of recanalization after thrombosis of culprit vessel for EL. No patients suffered nontarget embolization, spinal ischemia, allergic reaction, post-EVAR rupture, or colonic ischemia. ConclusionsPrimary and secondary PASE proved to be a safe, effective, and durable tool in sac management in conjunction with EVAR. Treating ELs during or after EVAR with PASE has minimized the incidence of EL on CT scan and halted aneurysm growth in our cohort. Further studies are needed to confirm the long-term durability of PASE in reducing secondary interventions after EVAR.

5-Year Outcome for Endoleak Type 2 after Endovascular Treatment in Abdominal Aortic Aneurysm in Songklanagarind Hospital

Objective: To study the incidence rate of endoleak type 2 in patients with abdominal aortic aneurysm treated with endovascular procedures. The results in Songklanagarind Hospital 5 years ago. Methods: Retrospective research studies in patients receiving abdominal aortic aneurysm treatment using elective endovascular repair, retrospective studies from Jan 2012- Dec 2016 and have followed up for 2 years to evaluate the incidence of endoleak type II and physical factors such as gender, age, weight, height, body mass index, and any underlying illnesses that are related to the occurrence of leaks. Results: In the year 2012-2016, there was a collection of data of patients diagnosed with aneurysm that had elective surgery. A total of 250 patients underwent surgery, with an average age was 76 (70,80) years, representing 194 males (77.6%). The average size of aneurysms is 6 centimeters and the incidence of endoleak type II was 73 people (29%). In related factors, Dyspilipidemia is likely to cause a significant endoleak type II (P <0.001). At the same time, it is found that in the first year after surgery, there is a chance of endoleak type II. Conclusion: From this study, it was found that at the Songklanagarind Hospital, there was an endoleak type II 29% and found that the risk of dyslipidemia is related to the endoleak type II.

IP017. Chronic Anticoagulation Is Associated With Increased Rates of Reintervention for Endoleak Following Endovascular Aneurysm Repair

The literature is conflicting concerning the effect of chronic anticoagulation (AC) and antiplatelet (AP) therapy on endoleak following endovascular repair of abdominal aortic aneurysm (EVR). While there are data suggesting higher rates of endoleak in patients taking AC, it is still unknown whether AC or AP therapy predispose patients to clinically significant endoleak. The objective of this study is to evaluate the impact of these medications on the rate of both endoleak and reintervention following EVR. We included 14,798 patients abstracted from the Vascular Quality Initiative index hospitalization and long-term follow-up (LTF) datasets for EVR (2008-2016) were included in the analysis. LTF in Vascular Quality Initiative is recorded as 9 to 21 months after the index procedure (or longer if available). Patients not taking any anticoagulant, AP agent, or aspirin (ASA) postoperatively were excluded. Patients taking any combinations of anticoagulant and or AP agent (treatment) following the index procedure were compared against patients taking ASA alone (control). Primary end points were rate of follow-up endoleak and rate of reintervention for endoleak. There were 11,023 patients receiving ASA alone, 2761 receiving both ASA and another AP agent, 938 receiving ASA and AC, and 76 patients receiving all three medications. Treatment groups were different from the control for age, race, coronary artery disease and chronic obstructive pulmonary disease (Table I). Significant differences between control and treatment groups for aortic anatomy are shown in Table I. Combined endoleak (defined as any endoleak identified during index procedure or LTF) was significantly higher in every group taking more than ASA compared with the group on ASA alone (Table II). There were no statistically significant differences between any of the treatment groups and the control group for LTF endoleak. However, there is a significantly increased rate of reintervention for endoleak in the ASA + AC group, compared with ASA alone (19 [3.3%] vs 112 [1.8%]; P = .017). Additionally, analysis of variance also demonstrates a significant difference of combined endoleak between treatment groups; P = .005. This is the first study to evaluate the impact of AC and AP status on rate of reintervention for midterm endoleak following EVR. We demonstrate that the combination of ASA and AC therapy following EVR is associated with an increased rate of reintervention for endoleak. However, our findings show that dual-AP therapy has minimal effect on reintervention rate. Additional investigation may be needed to further delineate the relationship between AC and endoleak reintervention.Table IPatient demographicsControl (ASA alone)ASA + APASA + ACASA + AP and ACNo. (SE or %)No. (SE or %)P valueNo. (SE or %)P valueNo. (SE or %)P valueAge73.1 (0.08)72.6 (0.16).00475.9 (0.27).00073.1 (0.87).979White race9923 (90%)2475 (90%).548875 (93%).00166 (87%).288Hypertension9009 (81.8%)2463 (89.2%)<.001849 (90.6%)<.00168 (89.5%).099Coronary artery disease2890 (26.2%)1320 (47.8)<.001374 (39.9%)<.00151 (67.1%)<.001Chronic obstructive pulmonary disease3453 (31.3%)978 (35.4%)<.001367 (39.1%)<.00128 (36.8%).321AAA diameter, mm55.5 (0.14)54.7 (0.3).01555.9 (0.4).47255.5 (1.2).971Neck AAA angle <45°4249 (38.5%)925 (33.5%)<.001352 (37.5%).55233 (43.4%).409AAA, Abdominal aortic aneurysm; AC, anticoagulant; AP, antiplatelet; ASA, aspirin; SE, standard error.Boldface entries indicate statistical significance. Open table in a new tab Table IIEndoleak outcomesControl (ASA alone)ASA + APASA + ACASA + AP and ACNo. (%)No. (%)P valueNo. (%)P valueNo. (%)P valueCombined endoleak2978 (27)681 (24.7).012283 (30.2).03931 (40.8).009LTF endoleak781 (12.5)189 (12.3).86378 (13.4).5137 (17.1).345LTF endoleak requiring reintervention112 (1.8)24 (1.6).58819 (3.3).0170 (0)1.0AAA, Abdominal aortic aneurysm; AC, anticoagulant; AP, antiplatelet; ASA, aspirin; LTF, long-term follow-up.Boldface entries indicate statistical significance. Open table in a new tab

Aggressive Surveillance Is Needed to Detect Endoleaks and Junctional Separation between Device Components after Zenith Fenestrated Aortic Reconstruction

Junctional separation and resulting type IIIa endoleak is a well-known problem after EVAR (endovascular aneurysm repair). This complication results in sac pressurization, enlargement, and eventual rupture. In this manuscript, we review the incidence of this late finding in our experience with the Cook Zenith fenestrated endoprosthesis (ZFEN, Bloomington, IN). A retrospective review was performed of a prospectively maintained institutional ZFEN fenestrated EVAR database capturing all ZFENs implanted at a large-volume, academic hospital system. Patients who experienced junctional separation between the fenestrated main body and distal bifurcated graft (with or without type IIIa endoleak) at any time after initial endoprosthesis implantation were subject to further evaluation of imaging and medical records to abstract clinical courses. In 110 ZFENs implanted from October 2012 to December 2017 followed for a mean of 1.5years, we observed a 4.5% and 2.7% incidence of clinically significant junctional separation and type IIIa endoleak, respectively. Junctional separation was directly related to concurrent type Ib endoleak in all 5 patients. Three patients presented with sac enlargement. One patient did not demonstrate any evidence of clinically significant endoleak and had a decreasing sac size during follow-up imaging. The mean time to diagnosis of modular separation in these patients was 40months. Junctional separation was captured in surveillance in 2 patients and reintervened upon before manifestation of endoleak. However, the remaining 3 patients completed modular separation resulting in rupture and emergent intervention in 2 and an aortic-related mortality in the other. Junctional separation between the fenestrated main and distal bifurcated body with the potential for type IIIa endoleak is an established complication associated with the ZFEN platform. Therefore, we advocate for maximizing aortic overlap during the index procedure followed by aggressive surveillance and treatment of stent overlap loss captured on imaging.

Bifurcated-bifurcated aneurysm repair is a novel technique to repair infrarenal aortic aneurysms in the setting of iliac aneurysms

BackgroundUp to 40% of abdominal aortic aneurysms (AAAs) have coexistent iliac artery aneurysms (IAAs). In the past, successful endovascular repair required internal iliac artery (IIA) embolization, which can lead to pelvic or buttock ischemia. This study describes a technique that uses a readily available solution with a minimally altered off-the-shelf bifurcated graft in the IAA to maintain IIA perfusion. MethodsFrom August 2009 to May 2015, 14 patients with AAAs and coexisting IAAs underwent repair with a bifurcated-bifurcated approach. A 22-mm or 24-mm bifurcated main body device was used in the IAA with extension of the “contralateral” limb into the IIA. Intraoperative details including operative time, fluoroscopy time, and contrast agent use were recorded. Outcome measures assessed were operative technical success and a composite outcome measure of IIA patency, freedom from reintervention, and clinically significant endoleak at 1 year. ResultsFourteen patients underwent bifurcated-bifurcated repair during the study period. Technical success was achieved in 93% of patients, with successful treatment of the AAA and IAA and preservation of flow to at least one IIA. The procedure was performed with a completely percutaneous bilateral femoral approach in 92% of patients. Three patients had a type II endoleak on initial follow-up imaging, but none were clinically significant. There were no cases of bowel ischemia or erectile dysfunction. One patient had buttock claudication ipsilateral to IIA coil embolization (contralateral to bifurcated iliac repair and preserved IIA) that resolved by 6-month follow-up. Two patients required reinterventions. One patient presented to his first follow-up visit on postoperative day 25 with thrombosis of the right external iliac limb ipsilateral to the bifurcated iliac repair, which was successfully treated with thrombectomy and stenting of the limb. This same patient presented at 83 months with growth of the preserved IIA to 3.9 cm and underwent coil embolization of the aneurysm. Another patient presented for surveillance 44 months after his original repair with component separation of the mating stent and the iliac bifurcated stent grafts. This was treated with a limb extension and endoanchors to fuse the endografts. Of the 13 patients who underwent bifurcated-bifurcated repair, 100% of the preserved IIAs remained patent at last follow-up. The composite outcome measure of IIA patency and freedom from reintervention and clinically significant endoleak at 1 year was 92% (n = 12/13). ConclusionsIn this small retrospective review, bifurcated-bifurcated aneurysm repair of aortoiliac aneurysms with preservation of perfusion to the IIA is technically feasible and safe with good short-term and midterm results in male patients.

Systemic Inflammatory Disease and Its Association With Type II Endoleak and Late Interventions After Endovascular Aneurysm Repair.

Abdominal aortic aneurysms are associated with chronic inflammation within the aortic wall, and previous studies have suggested that chronic inflammation may be a consequence of a dysregulated and persistent autoimmune response. Persistent aortic remodeling after aneurysm repair could place the patient at risk for endoleak or sac rupture. To determine whether patients with systemic inflammatory disease and large aneurysms have persistent aortic remodeling after endovascular aneurysm repair (EVAR). The records of all patients who underwent EVAR between July 2002 and June 2011 at the Veterans Affairs Connecticut Healthcare System were included in this retrospective review. Patients were considered to have a systemic inflammatory disease when confirmed by a referring specialist. Post-EVAR surveillance was performed by yearly imaging. Endovascular aneurysm repair. Significant endoleak, defined as endoleak and sac diameter increase of 0.5 cm or greater. A total of 51 of 79 patients (65%) had a systemic inflammatory disease. These patients had similar comorbid conditions compared with patients without inflammation but significantly greater numbers of major postoperative complications after EVAR (23.5% vs 3.6%; P = .02) and overall postoperative complications after EVAR (27.5% vs 7.1%; P = .03). Patients with a history of systemic inflammatory disease developed more endoleaks (45.1% vs 17.9%; P = .02) and late sac expansion (51.0% vs 21.4%; P = .01) and required more interventions (21.6% vs 3.6%; P = .03) during long-term follow-up. Systemic inflammatory disease was significantly associated with significant endoleak (odds ratio, 5.18; 95% CI, 1.56-17.16; P = .007). Patients with systemic inflammatory disease are at high risk for postoperative complications, type II endoleak, sac expansion, and additional interventions after EVAR. Additional strategies for improving the efficacy of EVAR in these patients may be warranted.

Outcomes Following Limb Crossing in Endovascular Aneurysm Repairs.

Crossing the limbs of the stent during endovascular aneurysm repair (EVAR) is often used to aid cannulation of the contralateral limb. This study assessed outcomes following the use of this technique. Retrospective review of crossed (n = 43) and uncrossed (n = 269) EVARs was performed at a tertiary vascular center over 5 years. Primary end points were graft limb occlusion (GLO), endoleak, and sac expansion rates. Indications for limb crossing were also assessed. Two-year GLO (P = .34) and type 1 endoleak (P = .413) rates were similar between groups. Patients undergoing crossed EVAR experienced more type 2 endoleaks (P = .002) at 24 months but no increase in sac expansion rates was observed (P = .275). Thirty-day (P = .57) and late (P = .268) mortalities were similar between groups. The main indication for limb crossing was distal aortic angulation (48.8%). Crossed EVAR does not increase the risk of GLOs or clinically significant endoleaks. Further studies are needed to determine the effect on type 2 endoleak rates.

044 Endovascular and transcatheter management of coarctation-related aneurysms in adults

IntroductionAortic coarctation surgery is associated with a late risk of aneurysm formation. This is particularly seen with patch aortoplasty repair. These aneurysms have a high risk of rupture in the...

Calcium channel blockers enhance sac shrinkage after endovascular aneurysm repair

Sac shrinkage is a surrogate marker of success after endovascular aneurysm repair (EVAR). We set out to determine if any common cardioprotective medications had a beneficial effect on sac shrinkage. This retrospective observational study took place at Leeds Vascular Institute, a tertiary vascular unit in the Northern United Kingdom. The cohort comprised 149 patients undergoing EVAR between January 1, 2005, and December 31, 2008. Medication use was recorded at intervention (verified at study completion in 33 patients), and patients were monitored for 2 years. The main outcome measures were the effect of medication on sac shrinkage as determined by percentage change in maximal idealized cross-sectional area of the aneurysm at 1 month, 6 months, 1 year, and 2 years by linear regression model, in addition to 2-year endoleak and death rates determined by a binary logistic regression model. After exclusions, 112 patients, who were a median age of 78 years (interquartile range, 78-83 years), remained for analysis. The median Glasgow Aneurysm Score was 85 (interquartile range, 79-92). At 2 years, mortality was 13.4%, endoleak developed in 37.5%, and significant endoleak developed in 14.3%. Patients taking a calcium channel blocker had enhanced sac shrinkage, compared with those not taking a calcium channel blocker, by 6.6% at 6 months (-3.0% to 16.3%, P = .09), 12.3% at 1 year (2.9% to 21.7%, P = .008), and 13.1% at 2 years (0.005% to 26.2%, P = .007) independent of other medication use, graft type, endoleak development, or death. Enhanced sac shrinkage occurred after EVAR in patients taking calcium channel blockers. This warrants further study in other centers and at the molecular level.

Hybrid Stent-Graft Repair of an Iatrogenic Complex Proximal Right Common Carotid Artery Injury

Iatrogenic carotid trauma requires early diagnosis and adequate treatment. Classic open repair may be technically challenging if trauma is in base of the neck. We present a case of an iatrogenic carotid pseudoaneurysm treated with endovascular repair. An 87-year-old woman presented with a pulsatile neck mass 10 days after coronary artery bypass graft surgery. A computed tomographic angiogram showed a 1.6 × 1.0 × 2.0-cm pseudoaneurysm arising from the posterior wall of the proximal right common carotid artery. Endovascular management was considered, and a percutaneous angiogram demonstrated an arteriovenous fistula in addition to the pseudoaneurysm. Through a cervical cut-down, retrograde percutaneous access was obtained through the common carotid artery, which allowed easier access to the area of trauma owing to vessel tortuosity. Subsequently, a 5 mm × 2-cm Viabahn was deployed. The postdilation angiogram showed a significant endoleak that kept filling the pseudoaneurysm. A second 6mm × 5-cm Viabahn was placed and successfully postdilated with a 6 mm × 4-cm balloon. No endoleaks or fistulas were noted on the completion angiogram. The patient remains asymptomatic after 15 months. Follow-up images showed thrombosis of pseudoaneurysm. Endovascular treatment with self-expanding stent-grafts and open cut-down access are excellent options to treat major vessel injuries at the base of the neck, where anatomy and cumbersome access make open surgery a more difficult option.

Elective visceral hybrid repair of type III thoracoabdominal aortic aneurysm

According to the classification given by Crawford et al. type III thoracoabdominal aortic aneurysm (TAAA) is dilatation of the aorta from the level of the rib 6 to the separation of the aorta below the renal arteries, capturing all the visceral branch of aorta. Visceral hybrid reconstruction of TAAA is a procedure developed in recent years in the world, which involves a combination of conventional, open and endovascular aortic reconstruction surgery at the level of separation of the left subclavian artery to the level of visceral branches of aorta. We presented a 75-years-old man, with elective visceral hybrid reconstruc tion of type III TAAA. Computerized scanning (CT) angiography of the patient showed type III TAAA with the maximum transverse diameter of aneurysm of 92 mm. Aneurysm started at the level of the sixth rib, and the end of the aneurysm was 1 cm distal to the level of renal arteries. Aneurysm compressed the esophagus, causing the patient difficulty in swallowing act, especially solid food, and frequent back pain. From the other comorbidity, the patient had been treated for a long time, due to chronic obstructive pulmonary disease and hypertension. In general endotracheal anesthesia with epidural analgesia, the patient underwent visceral hybrid reconstruction of TAAA, which combines classic, open vascular surgery and endovascular procedures. Classic vascular surgery is visceral reconstruction using by-pass procedure from the distal, normal aorta to all visceral branches: celiac trunk, superior mesenteric artery and both renal arteries, with ligature of all arteries very close to the aorta. After that, by synchronous endovascular technique a complete aneurysmal exclusion of thoracoabdominal aneurysm with thoracic stent-graft was performed. The postoperative course was conducted properly and the patient left the Clinic for Vascular Surgery on postoperative day 21. Control CT, performed 3 months after the surgery showed that the patient's vascular status was uneventful with functional visceral by-pass and with good position of a stent-graft without a significant endoleak. Visceral hybrid reconstruction represents a complementary surgical technique to that with open reconstruction of TAAA. This approach is far less traumatic to a patient, and is especially important in patients with lot of comorbidities, because there is no need for thoracotomy, and ischemic-reperfusion injury of the body is reduced to a minimum.

Endovascular infrarenal aneurysm repair in patients with horseshoe kidneys: case series and literature review

Horseshoe kidney may cause technical and access problems during open aortic aneurysm repair. The aim of this study is to report two cases from our institution and to review the world's literature on successful endovascular infrarenal aneurysm repair in patients with horseshoe kidneys. A retrospective review of a prospectively entered departmental computerized database was performed for the two patients from our institution. Articles were searched electronically from PubMed and Medline, using the terms 'horseshoe kidney' and 'aneurysm'. Endovascular cases were reviewed from the world's literature. In addition to the two patients from our institution, there were 19 patients with infrarenal aneurysms and horseshoe kidneys in published literature who underwent successful endovascular aneurysm repair. The occlusion of lower-pole or accessory renal arteries does not seem to cause significant endoleak or renal impairment in the long run. In conclusion, our experience and current literature seem to suggest that endovascular repair of infrarenal aortic aneurysms for patients with horseshoe kidneys is safe. Renal impairment will depend on the area of kidney perfused by the accessory renal arteries. The endovascular treatment option is less invasive than open repair, and circumvents the problem of difficult exposure, especially in those patients with significant co-morbidity.

Utility of Noninvasive Aneurysm Sac Pressure Measurement During and After Endovascular Abdominal Aortic Aneurysm Repair

Purpose The utility of noninvasive pressure sensors in the intra- and postoperative settings is not entirely clear. The objectives of this study were to determine intraoperative pressure criteria in the setting of technically successful endovascular aneurysm repair (EVAR) and to evaluate pressure changes during follow-up. Materials and Methods A total of 55 patients (42 men) underwent attempted noninvasive sensor monitor placement within the aneurysm sac. Pressures were recorded before and after EVAR. Recordings were repeated at 1 day, 2 weeks, 3 months, and 1 year. Clinical data, pressure recordings, and computed tomography were retrospectively assessed. Results Noninvasive pressure sensors were successfully placed in 51 patients. The mean intraoperative decreases in pulse pressure (PP) and PP ratio (PPR) in the setting of technical success were statistically different versus (i) baseline recordings and (ii) pressures obtained in the setting of type I endoleak (74.2% vs 41.5% and 76.2% vs 46.5%, respectively). At follow-up, there were continued decreases in PP and PPR, with a decrease in mean pressure resuming at the 3-month interval. Four of 14 type II endoleaks were treated because of relatively increased pressure with stable or increased aneurysm size. Conclusions An intraoperative decrease in PP and PPR in the range of approximately 70% after EVAR was associated with successful aneurysm exclusion. Noninvasive sensors can provide useful ancillary information in confirming technical success intraoperatively. During follow-up, an increase in sensor pressure recordings may be suggestive of clinically significant endoleak; however, further research is necessary.

Long-term results of balloon-expandable LifePath endografts in abdominal aortic aneurysm: A single-center experience

This retrospective single-center study analyzed long-term results after LifePath (Edwards Lifesciences LLC, Irvine, Calif) endoprosthesis implantation for abdominal aortic aneurysm (AAA), primarily focusing on the wire form fracture issue and consecutive endoleak rate. Between 1999 and 2004, all consecutive patients with LifePath AAA devices in our institution were included in the retrospective analysis. All patients had computed tomography angiography (CTA) imaging preoperatively and image postprocessing. The follow-up using CTA imaging specifically addressed material fatigue (wire form fractures) resulting in migrations and type I endoleaks. During the 6-year study period, which included the 1-year withdrawal and redesign of the device, 51 patients were treated with LifePath AAA endografts. The 30-day mortality was 0%. The perioperative 30-day morbidity was 9.8%. One patient required a primary conversion due to misdeployment of the iliac limbs within the graft main body. The primary endoleak rate was 20.56% (type I, 2%; type II, 19.6%). During the mean follow-up of 40.7 months, 12 patients died, six were lost to follow-up, and 32 underwent subsequent CTA imaging. Eight patients (25%) demonstrated a proximal type I endoleak, seven (22%) had a type II endoleak, and three had a type III endoleak (9%). In nine patients (28.1%), wire form fractures could be detected at image postprocessing. Four patients required a secondary conversion due to endoleak and aneurysm growth (2 type I endoleaks and 2 type III endoleaks). Wire form fracture is the major structural problem in the LifePath balloon-expandable endograft device, resulting in a significant endoleak rate. We must caution those patients with a LifePath device in-situ that careful follow-up must be performed due to material fatigue and they should consider secondary conversion.

Endoleak Detection with CT Angiography in an Abdominal Aortic Aneurysm Phantom: Effect of Tube Energy, Simulated Patient Size, and Physical Properties of Endoleaks

To analyze the detection of endoleaks with low-tube-voltage computed tomographic (CT) angiography. A cylindrical plastic phantom mimicking an aortic aneurysm, containing a stent graft and 36 simulated endoleaks of various diameters, densities, and distances from the graft, was placed into three different water containers corresponding to small, intermediate-sized, and large patients. CT was performed at 80, 100, and 120 kVp, and the volume CT dose index (CTDI(vol)) was noted. Three radiologists independently analyzed the CT images for endoleak localization with diagnostic confidence and for image quality. Analysis of variance was used to compare results and to find parameters that have an effect on endoleak detection. All 6-mm endoleaks were correctly identified at all tube energies except for five endoleaks at 80 kVp in the thick phantom. Observers detected more 4-mm leaks at higher tube voltage in the thick phantom (P < .001) and at 100 kVp compared with 80 kVp in the intermediate phantom (P = .006). Compared with CTDI(vol) at 120 kVp, CTDI(vol) was lower by nearly 50% at 80 kVp in the thin and intermediate phantoms and at 100 kVp in the thick phantom. Endoleak diameter, position, phantom dimension, and tube voltage all had a significant effect on the number of detected leaks (P < .0001). This phantom study suggests that reduced radiation exposure is achievable with CT angiography at 80 kVp in small and intermediate-sized patients and at 100 kVp in large patients, with no increased risk of missing significant endoleaks measuring 6 mm or larger.

Abstract 6192: Endovascular Stent-Graft Repair of Type B Aortic Dissection: Intermediate to Long-Term Results

The aim of this study is to assess mid- to long-term clinical results of the endovascular stent-graft repair in patients with type B aortic dissection. Retrospective analysis was done on 73 patients (average age: 55.6 ± 12.4) who underwent stent-graft repair at our center from June 1994 to December 2007. The indications of case selection were progression of dissection despite adequate medical treatment, dynamic obstruction, intractable pain, aortic diameter of 6cm or more, or continuous false lumen leakage in either acute or chronic presentation. Median follow-up duration was 43 months (5 ~ 97 months, 64.4 ± 38.8 months). There was an absence of immediate postprocedural mortality or paraplegia. Angiographic success, defined as immediate closure of entry site without any significant endoleak, was obtained in 67/73 (91.7%) patients. Clinical success, defined as the complete obliteration or complete thrombosis of the false lumen at follow-up, was achieved in 53/73 (72.6%) patients. 22/73 (30.1%) patients demonstrated complications such as persistent type I endoleak, false lumen flow patency at distal portion of stent-graft, and 5/73 (6.8%) patients such as type II endoleak. Among these endoleaks, 5 cases were progressed and 17 cases were remained unchanged. There were unintended left subclavian artery occlusion (1 case), transient acute renal failure (1 case), saccular aneurysm (5 cases) and stent-graft migration or torsion (2 cases) as complications. During medial follow-up 43 months, 4 patients (5.5%) were died. In conclusion, cIinical outcomes of stent-graft repair of type B aortic dissection were favorable and should be considered as a safe and effective treatment option of type B aortic dissection, particularly in patients with a high risk surgical mortality or mobility.