Abdominal Aortic Aneurysm Sac Research Articles

Endovascular Abdominal Aortic Aneurysm Repair Preserving A Right Crossed Unfused Inferior Ectopic Kidney

An 80 year old man presented with a 41 mm abdominal aortic aneurysm (AAA), a 35 mm right common iliac artery aneurysm, and also right crossed inferior non-fused renal ectopia resulting from disrupted embryonic kidney migration and impaired ureteric bud migration to the opposite side. The left upper renal artery (red arrow) for left kidney (red arrowheads) stemmed from the usual aortic level (L1/L2) and the left lower renal artery (blue arrow) for the ectopic kidney (blue arrowheads) arose from the AAA sac (A). The aneurysms were repaired using a custom made branched tube graft to the lower renal artery and a right iliac branched graft (Cook Aortic Intervention, Bloomington, IN, USA) (B). We thank Jairo Garcia (jairoillustrations@gmail.com) for his artistic illustrations.Figure 1

Characteristics and Outcomes of Ruptured Abdominal Aortic Aneurysms Below the Size Threshold for Elective Repair

The current guidelines recommend elective abdominal aortic aneurysm (AAA) repair at 5.5 cm in men and 5.0 cm in women. However, rupture occurs in patients with aneurysm size below these thresholds. This study aimed to investigate the proportion of small ruptured AAAs (rAAAs) below elective operative thresholds and to compare outcomes of repair with larger aneurysms. The 2011 to 2018 American College of Surgeons National Surgical Quality Improvement Program open and endovascular AAA repair databases were reviewed for all cases of rAAA. Patients were divided into two groups: small rAAA for those who present below size thresholds and large rAAA for the remainder. The proximal/distal extent of rAAA and the preoperative characteristics and outcomes of infrarenal rAAA were compared. Of the 1612 ruptured AAA repairs, 167 (10.4%) were small rAAAs. The proportion of small rAAA did not significantly change during the study period (P = .15; Fig). Patients in the large rAAA group were more likely to have juxtarenal or suprarenal aneurysms (27% vs 16%; P = .001). Patients in the small infrarenal rAAA group had significantly lower body mass index and were more likely to be African American and to have hypertension. Patients in the small AAA group were more likely to be assigned to American Society of Anesthesiologists class ≤3 and to undergo endovascular aneurysm repair but less likely to have hypotension on presentation. Repair of small rAAA was associated with lower bleeding, mortality, and mean operative time and higher readmission (Table). Multivariate analysis showed that rupture with hypotension, open repair, general anesthesia, age, and high American Society of Anesthesiologists class were associated with increased mortality, but aneurysm size was not. Current guidelines for elective repair based solely on AAA sac diameter fail to identify 10% of patients presenting with rupture. Ruptured AAA carries significant mortality regardless of the size of the aneurysm. Further research into sac morphology and more sensitive imaging modalities may help identify small rAAA at high risk of rupture that would benefit from elective repair.TableDemographics, comorbidities, operative characteristics, and outcomes of ruptured abdominal aortic aneurysm (rAAA)Small infrarenal rAAALarge infrarenal rAAAP valueTotal141 (100)1051 (100)Age, years <503 (2.1)40 (3.8) 51-6429 (20.5)200 (19.0) 65-7942 (29.7)311 (29.5) 80+56 (39.7)371 (35.3).86 Mean (SD)71.8 (11.6)70.8 (11.8).38Male sex105 (74.4)817 (77.7).38Functional status.16 Dependent8 (5.6)35 (3.3)BMI, kg/m2<.02 <1814 (9.9)95 (9.0) 18-2447 (33.3)217 (20.6) 25-3039 (27.6)282 (26.8) 30-3412 (8.5)188 (17.8) 35+16 (11.3)134 (12.7)BMI, kg/m2, mean (SEM)26.1 (0.6)27.8 (0.2)Height, inches, mean (SEM)67.6 (0.3)67.7 (0.1).65Weight, kg, mean (SEM)80.3 (1.8)86.8 (0.7)<.01Race White102 (72.3)790 (75.1) African American17 (12.1)53 (5.0)<.01 Other22 (15.6)208 (19.7)Comorbidities Diabetes mellitus22 (15.6)144 (13.7).54 Current smoker52 (36.8)401 (38.1).76 COPD26 (18.4)162 (15.4).35 CHF3 (2.1)32 (3.0).54 HTN106 (75.1)692 (65.8).02 Current dialysis3 (2.1)16 (1.5).59Presentation AAA diameter, mean (SEM)4.4 (0.1)8.0 (0.1)<.01 Rupture with hypotension47 (33.3)521 (49.5)<.01Surgical technique EVAR111 (78.7)685 (65.1)<.01 Open30 (21.2)366 (34.8)Anesthesia technique GA126 (89.3)959 (91.2) Other15 (10.6)92 (8.7).46ASA class ≥499 (70.2)862 (82.0)<.01Operating time, minutes, mean (SEM)163.7 (8.9)182.3 (8.9).03Complications Wound infection5 (3.5)36 (3.4).94 Pneumonia10 (7.0)100 (9.5).35 Unplanned intubation11 (7.8)93 (8.8).67 Failed vent weaning24 (17.0)224 (21.3).23 Cardiac arrest10 (7.0)103 (9.8).3 Myocardial infarction6 (4.2)90 (8.5).07 Stroke2 (1.4)20 (1.9).68 Bleeding77 (54.6)713 (67.8)<.01 DVT/thrombophlebitis4 (2.8)39 (3.7).6 Sepsis11 (7.8)108 (10.2).35 Renal failure1 (0.7)11 (1.0).7 Ischemic colitis8 (5.6)81 (7.7).38 Repeated rupture of aneurysm7 (4.9)61 (5.8).68 Lower extremity ischemia3 (2.1)50 (4.7).15 Any morbidity92 (65.2)776 (73.8).03Mortality24 (17.0)260 (24.7).04Readmission19 (13.4)60 (5.7)<.01Reoperation23 (16.3)151 (14.3).53Hospital length of stay, days (SD)9.78 (12.2)9.71 (15.2).84ASA, American Society of Anesthesiologists; BMI, body mass index; COPD, chronic obstructive pulmonary disease; CHF, congestive heart failure; DVT, deep venous thrombosis; EVAR, endovascular aneurysm repair; GA, general anesthesia, HTN, hypertension; SD, standard deviation; SEM, standard error of the mean.Values are reported as number (%) unless otherwise indicated. Boldface P values represent statistical significance. Open table in a new tab

Comparison of Abdominal Aortic Aneurysm Sac and Neck Wall Motion with 4D Ultrasound Imaging

The rupture of abdominal aortic aneurysms (AAAs) is associated with high mortality despite surgical developments. The determination of aneurysm diameter allows for follow up of aneurysm growth but fails in precisely predicting aneurysm rupture. In this study, time resolved three dimensional ultrasound (4D ultrasound) based wall motion indices (WMIs) are investigated to see if they are capable of distinguishing between uneven affected regions of the aneurysm wall. In a prospective study, 56 patients with an AAA were examined using 4D ultrasound. Local longitudinal, circumferential, and shear strains were computed using custom methods. The deformation of the neck and sac of each aneurysm was characterised by statistical indices of the obtained distributions of local wall strains (WMIs): mean and peak strain, heterogeneity index, and local strain ratio. The locations of regions with highest local peak strain were determined. Compared with the aneurysm neck, the sac is characterised by low mean strain, but highly heterogeneous deformation, described by high local strain ratio and heterogeneity index. Differences were highly significant (p<.001) for all strain components. The regions with the highest circumferential peak strain were found more often in the posterior part of the aneurysm neck (p<.050) and sac (p<.001) regions, compared with other wall regions. No statistically significant correlation was found between the WMIs and maximum AAA diameter, except for longitudinal mean strain, which decreased with the increasing diameter (rho=-.42, p<.010). Characterisation of wall kinematics by 4D ultrasound based WMIs provides a new and independent criterion for the distinction of diseased tissue in the AAA sac and the less affected neck region. This is a promising step towards the establishment of new biomarkers to differentiate between the mechanical instability of the AAA and rupture risk.

Intra-abdominal Aortic Aneurysm Sac Angiography After Endovascular Aortic Repair Predicts Type II Endoleak

Incidence of type II endoleak (T2E) is a major concern as a negative late outcome after endovascular aneurysm repair (EVAR). Since 2015, we have performed n-butyl-2-cyanoacrylate (NBCA) injection into the abdominal aortic aneurysm (AAA) sac during EVAR for prevention of T2E. As an assistant of NBCA injection, intra-aneurysm sac angiography (IASA) has been performed for confirming the patent lumbar artery (LA). Although we reported a satisfactorily reduced incident rate of T2E by NBCA injection, there was a question of whether NBCA injection was routinely necessary for all EVARs. The aim of this study was to evaluate the relationship between T2E after EVAR and the finding of no contrasted LA on IASA. During EVAR, a 5F catheter was placed into the aneurysm sac from the contralateral side of the femoral artery before deployment of aortic stent grafts. For cases without type I and type III endoleak by completion digital subtraction angiography, IASA was performed to look for the patent LA. Between November 2017 and December 2019, there were 76 patients who underwent IASA during EVAR. Among them, we evaluated non-NBCA-injected patients because LA was not identified by IASA. The incidence of T2E at 7 days and the AAA sac diameter at 6 months after EVAR were evaluated by contrast-enhanced and plain computed tomography (CT), respectively. Among patients undergoing IASA, there were 14 patients (18.4%) in whom patent LA was not identified by IASA during EVAR. Preoperative AAA mean diameter was 54.1 ± 8.8 mm. Patent LAs were identified in 11 patients by preoperative contrast-enhanced CT. The mean number of patent LA pairs was 1.8 ± 1.3. Preoperative contrast-enhanced CT also identified patent inferior mesenteric artery in six cases, and five were coil embolized during EVAR. EVAR was performed using one of five stent grafts: Endurant (Medtronic, Santa Rosa, Calif), four; AFX2 (Endologix, Irvine, Calif), four; Aorfix (Lombard Medical, Irvine, Calif), three; Zenith Alpha Abdominal (Cook Medical, Bloomington, Ind), two; and Excluder (W. L. Gore & Associates, Flagstaff, Ariz), one. Postoperative contrast-enhanced CT at 7 days showed no T2E in all patients. Postoperative CT at 6 months was performed in seven patients. It showed AAA sac shrinkage in five patients (71.4%) and no AAA sac enlargement. IASA after EVAR might be able to predict no T2E when LAs are not identified on IASA.

Characteristics and Outcomes of Ruptured Abdominal Aortic Aneurysms Below the Size Threshold for Elective Repair

The current guidelines recommend elective abdominal aortic aneurysm (AAA) repair at 5.5 cm in men and 5.0 cm in women. However, rupture can occur in patients with aneurysm below these size thresholds. This study aims to investigate the proportion of AAA that rupture below elective operative thresholds and compare the outcomes of repair to ruptured aneurysm at larger size in a national database. The American College of Surgeons National Surgical Quality Improvement Program targeted vascular files for open AAA repair and endovascular aneurysm repair (EVAR) were reviewed for all cases of ruptured AAA between 2011 and 2018. Patients were divided into two groups: small AAA for those that presented with ruptured aneurysms below current size guidelines and large AAA for those that met size criteria for elective repair. The proportion of infrarenal AAA between the two groups was determined. The comorbidities and perioperative outcomes of infrarenal AAA repair in both groups were compared. Of the 1612 ruptured AAA repairs, 167 (10.4%) were small AAAs. The proportion of small AAA ruptures did not significantly change during the study period (P = .15) (Figure). Patients in the large AAA group were more likely to have juxtarenal or suprarenal aneurysms compared to patients in the small AAA group (27% vs 16%; P = .001). Comparison of infrarenal AAA only demonstrated that the mean small AAA (n = 141) diameter was 4.41 (range, 2-5.4cm) compared to large AAA (n = 1051) mean diameter of 8.03 cm (range, 5-20 cm) (P < .01) (Table). Patients in the small AAA group had significantly lower body mass index and mean body weight and were more likely to present with hypotension compared to patients with large AAA. Patients in the small AAA group were more likely to have American Society of Anesthesiologists classification of ≤3 and to undergo EVAR. Repair of small ruptured aneurysms was also associated with lower bleeding, mortality, and mean operative time; but had higher readmissions rates. Multivariable regression demonstrated that dependent functional status (odds ratio [OR], 2.5; 95% confidence interval [CI], 1.2-5.3), rupture with hypotension (OR, 3.4; 95% CI, 2.5-4.8), American Society of Anesthesiologists class ≥4 (OR, 2.5; 95% CI, 1.4-4.7), and open repair compared to EVAR (OR, 1.9; 95% CI, 1.3-2.6) were associated with increased mortality but not aneurysm size. Current guidelines for elective repair based solely on AAA sac diameter fail to identify at least 10% of patients that present with rupture. Rupture of infrarenal AAA carries significant mortality regardless of the size of the aneurysm at the time of rupture. Further research into sac morphology and more sensitive imaging modalities may help identify small AAA at high risk of rupture that would benefit from elective repair.TableCharacteristics of infrarenal small and large ruptured abdominal aortic aneurysm (AAA) repairsSmall AAAn = 141Large AAAn = 1051P valueAge, years.38 <503 (2.13)40 (3.81) 51-6429 (20.57)200 (19.03) 65-7942 (29.79)311 (29.59) 80+56 (39.72)371 (35.3) Mean ± standard deviation71.8 ± 11.6570.89 ± 11.84Sex.38 Male105 (74.47)817 (77.74)Functional status.16 Dependent8 (5.67)35 (3.33)BMI <1814 (9.93)95 (9.04).07 18-2447 (33.33)217 (20.65).17 25-3039 (27.66)282 (26.83).84 30-3412 (8.51)188 (17.89).07 35+16 (11.35)134 (12.75).38 Mean26.0527.77.02Mean height67.667.7.65Mean weight177.1191.4<.01Race White102 (72.34)790 (75.17).46 Other39 (27.66)261 (24.83)Comorbidities Diabetes mellitus22 (15.6)144 (13.7).54 Current smoker52 (36.88)401 (38.15).76 COPD26 (18.44)162 (15.41).35 CHF3 (2.13)32 (3.04).54 HTN106 (75.18)692 (65.84).02 Current dialysis3 (2.13)16 (1.52).59Presentation Mean AAA diameter (cm)4.41 ± 0.068.03 ± 0.06<.01 Rupture with hypotension47 (33.33)521 (49.57)<.01Surgical technique EVAR111 (78.72)685 (65.18)<.01 Open30 (21.28)366 (34.82)Principal anesthesia technique General126 (89.36)959 (91.25) Other15 (10.64)92 (8.75)ASA class.46 ≤342 (29.79)189 (17.98) ≥499 (70.21)862 (82.02)<.01Emergency case Yes102 (72.34)888 (84.49)<.01Mean operating time, minutes163.79 ± 8.99182.39 ± 8.99.03Adverse events Wound infection5 (3.55)36 (3.43).94 Pneumonia10 (7.09)100 (9.51).35 Unplanned intubation11 (7.8)93 (8.85).67 Failed vent weaning24 (17.02)224 (21.31).23 Cardiac arrest10 (7.09)103 (9.8).3 Myocardial infarction6 (4.26)90 (8.56).07 Stroke2 (1.42)20 (1.9).68 Bleeding77 (54.61)713 (67.84)<.01 DVT/thrombophlebitis4 (2.84)39 (3.71).6 Sepsis11 (7.8)108 (10.28).35 Renal failure1 (0.71)11 (1.05).7 Ischemic colitis8 (5.67)81 (7.71).38 Repeat repair of aneurysm7 (4.96)61 (5.8).68 Lower extremity ischemia3 (2.13)50 (4.76).15Any morbidity104 (73.76)808 (76.88).41Mortality24 (17.02)260 (24.74).04Readmission within 30 days19 (13.48)60 (5.71).005Reoperation23 (16.31)151 (14.37).53Hospital length of stay, days9.78 (12.20)9.71 (15.22).84ASA, American Society of Anesthesiologists,; BMI, body mass index; CHF, congestive heart failure; COPD, chronic obstructive pulmonary disease; DVT, deep vein thrombosis; EVAR, endovascular aneurysm repair; HTN, hypertension. Open table in a new tab

Unibody Endograft Using AFX 2 for Less Invasive and Faster Endovascular Aortic Repair: Protocol for a Multicenter Nonrandomized Study.

BackgroundSince the introduction of endovascular aortic repair (EVAR) for treatment of abdominal aortic aneurysms (AAAs), progressive improvements in results have been achieved. However, conventional bifurcated stent grafts have been proven to have a nonnegligible risk of failure and secondary intervention, principally due to the lack of adequate proximal sealing. The unique AFX 2 Endovascular AAA System (Endologix, Irvine, CA) unibody device, which provides different sealing and fixation features compared with conventional devices, seems to overcome these limitations.ObjectiveThe aim of this study is to evaluate intraoperative, perioperative, and postoperative results in patients treated with the AFX 2 Endovascular AAA System endografts for elective AAA repair in a large cohort of consecutive patients.MethodsAll eligible EVAR patients will be included in this observational, multicenter, prospective, nonrandomized study. The number of patients to be enrolled is 500.ResultsThe primary endpoint of the study is to evaluate the technical and clinical success of EVAR with unibody endografts in short- (90-day), mid- (1-year), and long-term (5-year) follow-up periods. The following secondary endpoints will also be addressed: operative time, intraoperative radiation exposure, contrast medium usage, AAA sac shrinkage at 12-month and 5-year follow-up, and any potential role of patients’ baseline characteristics and device configuration on primary endpoint. The actual start date of the investigation was November 2019. The final patient is expected to be treated by the end of December 2020, and the estimated study completion date is December 2025.ConclusionsThis study will provide verified real-world data on AAAs treated by AFX 2 endografts and followed for a long-term interval.International Registered Report Identifier (IRRID)PRR1-10.2196/16959

Total Luminal Volume Predicts Risk after Endovascular Aneurysm Repair

Large aneurysm diameter represents a well known predictor of late complications after endovascular aneurysm repair (EVAR). However, the role of the thrombus free lumen inside the abdominal aortic aneurysm (AAA) sac is not clear. It was hypothesised that greater luminal volume represents a relevant risk factor for late complications after EVAR. A retrospective cohort analysis was performed including all patients undergoing EVAR from 2005 to 2016at a tertiary referral institution. Pre-operative AAA lumen volume was measured in centre lumen line reconstructions and patients were stratified into quartiles according to luminal volume. The primary endpoint was freedom from AAA related complications. Secondary endpoints were freedom from neck events (type 1A endoleak, migration>5mm or any pre-emptive neck related intervention), iliac related events (type 1B endoleak or pre-emptive iliac related intervention), and overall survival. Four hundred and four patients were included: 101 in the first quartile (Q1; <61cm3). Patients with higher luminal volumes had wider, shorter, and more angulated proximal necks. There were more ruptured AAAs, more aorto-uni-iliac implanted devices and patients outside neck instructions for use in the 4th quartile. Five year freedom from AAA related complications was 79%, 66%, 58% and 56%, respectively (p=.007). At five years, freedom from neck related events was 86%, 84%, 73%, and 71%, respectively, for the four groups (p=.009), and freedom from iliac related events was 96%, 91%, 88%, and 88%, respectively (p=.335). On multivariable analysis, luminal volume was an independent predictor of late complications (Q4 vs. Q1 - hazard ratio: 1.91, 95% confidence interval 1.01-3.6, p=.046). Overall survival at five years was not affected by lumen volume (p=.75). AAA luminal volume represents an important risk factor for AAA related complications. This information may be considered when deciding tailoring surveillance protocols after EVAR. However, larger studies are needed to validate this hypothesis.

Abdominal Aortic Aneurysm Sac Healing and Prevention of Endoleaks

Abdominal Aortic Aneurysm Sac Healing and Prevention of Endoleaks

Multicenter experience in translumbar type II endoleak treatment in the hybrid room with needle trajectory planning and fusion guidance

ObjectiveThe objective of this study was to evaluate the efficacy of treating type II endoleaks (T2Ls) after aortic endovascular repair with image guidance translumbar puncture using intraoperative cone beam computed tomography with preprocedure computed tomography angiography fusion in hybrid operating rooms. MethodsTwenty-six consecutive T2L patients in three different institutions were treated between March 2015 and September 2017 by direct translumbar puncture of the abdominal aortic aneurysm (AAA) sac after previous endovascular aortic repair. All patients were treated at a single setting in a cardiovascular hybrid operating room with a workstation featuring needle trajectory planning and guidance software. Aneurysm sac size change from the index treatment, freedom from recurrent endoleak after treatment, demographics, risk factors, and procedure factors were analyzed with univariate analysis. ResultsAll patients (N = 26; 19 male, 7 female; age range, 59-95 years; mean body mass index, 27.44 ± 3.06 kg/m2) underwent treatment for AAA sac expansion or symptoms. Four patients had failed to respond to previous catheter-directed T2L treatment. The most common risk factors included hypertension, hypercholesterolemia, coronary artery disease, tobacco use, and diabetes. Time to initial endoleak diagnosis ranged from 2 to 1914 days (average, 404 days). Aneurysm size after initial repair was 60.3 ± 7.5 mm; sac size had increased 10.1 ± 6.5 mm at the time of treatment. Onyx (Medtronic, Irvine, Calif) or glue (n-butyl cyanoacrylate) and coil embolization was used in 20 cases, and 6 patients were treated with coiling alone. There was no difference between the patients treated with coils alone and those treated with coils or glue (P > .05) in terms of freedom from failure. Total procedure time was 75.9 ± 40.7 minutes; contrast material volume, 19.9 ± 29 mL; fluoroscopy time, 13.74 ± 12.2 minutes; and radiation dose, 121.16 ± 167.7 mGy. After embolization, the mean sac diameter decreased by 2.2 mm to 67.5 ± 9.8 mm. Average follow-up period was 214 days. In 19 patients, the sac reduced in size between 0.2 and 19.1 mm per 100 days; in 2 patients, there was continued AAA expansion (3.4-4.3 mm per 100 days); there was no change in the sac size in 5 patients after the procedure. There were no AAA ruptures during the study period. Once T2L was treated, the recurrence rate was low at 11.5%. ConclusionsThis initial multicenter evaluation of the effectiveness of fusion image-guided translumbar obliteration of T2L demonstrated that the technique was effective at all three study centers and showed excellent efficacy to reduce AAA sac size. This may become a more effective and efficient method of treating T2L compared with transarterial or transcaval embolization because of its high success rate and technical ease.

Endovascular Aortic Aneurysm Repair without Type 2 Endoleak Using Concomitant N-Butyl-2-Cyanoacrylate Injection into the Abdominal Aortic Aneurysm Sac

The aim of this study was to evaluate our new method to occlude target lumber arteries using N-butyl-2-cyanoacrylate (NBCA) during endovascular aneurysm repair (EVAR) for prevention of type 2 endoleak (T2E). Between 2013 and 2018, 176 patients who underwent EVAR for abdominal aortic aneurysm (AAA) were reviewed. Starting from October 2015, 83 patients (treatment group) underwent NBCA injection into the aneurysmal sac during EVAR. The incidence of T2E at 7days and AAA sac diameter 12months after EVAR were compared with those of the control group comprising 93 consecutive patients who underwent EVAR alone before 2015. The incidence of T2E at 7days was significantly lower in the treatment group (2.4%) than in the control group (22.6%) (P<0.001). AAA sac diameter at 12months in the treatment group had a mean decrease of 6.6mm as compared with the mean 4.4mm in the control group (P=0.026). In multivariate analysis, NBCA injection was significantly related to the reduction of incidence of T2E at 7days (odds ratio=11.8, P<0.001) and a decrease in AAA sac diameter at 12months (P<0.001). There was no NBCA injection-related complication and reintervention in the treatment group. NBCA injection might be safe and useful to reduce the incidence of T2Es and to prevent AAA sac expansion.

Contrast Enhanced Ultra Sound (CEUS) for EVAR Monitoring: A New First Line Method for Post-operative Surveillance? A Single Center Experience

Introduction: EVAR (Endo Vascular Aortic Repair) is the first line therapy for the treatment of abdominal aortic aneurysms (AAA). The most frequent post-operative complications of EVAR are endoleaks (EL) that occur when blood leaks back into the aneurysm sac. Type II EL is the most frequent complication requiring lifelong surveillance by radiological imaging. Nowadays, according to guidelines, Computed Tomography Angiography (CTA) scan represents the gold standard modality of imaging to detect EL. CEUS (Contrast Enhanced Ultra Sound) is playing an emerging role in EL detection that could change the follow up algorithm in the near future, reducing the need for CTA imaging to selected cases. Methods: The purpose of the study is to evaluate the role of CEUS in detecting endoleaks after EVAR. Between 2014-2018, 111 patients treated with EVAR for AAA were collected, the mean follow up was 25 months; 14 patients (group 1) were enrolled in the group monitored by CT scan at 1, 6, 12 months and then once per year; 19 patients (group 2) in the group monitored by CEUS and CT scan at 1 month, by CEUS at 6 months and then by Ultrasound Scan (US) yearly; 59 patients (group 3) in the group monitored by CEUS at 1 and 6 months and then, in case of absence of complications, by US yearly. CTA was performed only in case of AAA sac's growth. During the follow-up, 2 patients died in peri-operative period for causes not related to EVAR and 17 patients have been dropped out (5 in group 1, 2 in group 2, 10 in group 3). Results: At the first month we reported 4 EL type II and 1 EL type 1b in group 1 (35%, 5/14), 6 EL type II and 1 EL 1b in group 2 (36%, 7/19) , 12 EL type II, 1 EL type 1b (22% 13/59) and 1 graft thrombosis of left iliac branch in group 3. Patients with type I EL have been promptly treated. All patients with type II EL have been monitored at 6 months, according to clinical and ultrasound presentation. We did not report deaths or major complication in patients with EVAR monitored only by CEUS. Five patients with type II EL and growth of the sac underwent to embolization with resolution of EL in 4 cases, while all the others EL type 2 resolved spontaneously or did not develop AAA growth. Conclusion: CEUS can provide additional contents in terms of dynamic images and flow patterns created by EL inside the AAA sac. The main disadvantages of this technique are operator dependency, lack of quantification, interpretation difficulties in complex anatomies and in high body mass index patients. Anyway, our results highlight the role of CEUS, compared to CT scan, in EVAR surveillance in terms of low cost, good diagnostic performance and, mostly, reduction of exposure to radiations and risk development of contrast medium induced nephropathy for patients needing a lifelong follow-up. Disclosure: Nothing to disclose

A simplified method of pre-emptive perigraft aortic sac embolization to prevent type II endoleak using the Excluder endograft

Pre-emptive, nonselective perigraft embolization of abdominal aortic aneurysm sac to reduce the risk of type II endoleak has been previously reported with a percutaneous technique using contralateral access with resheathing for coiling. The approach has been modified to simplify the procedure and to eliminate unnecessary sheath exchanges.

Decreased Abdominal Aortic Aneurysm Size Following EVAR in Patients With CT Evidence of Subclinical Thoracic Aortic Dissection

Aneurysm sac regression following endovascular repair (EVAR) of an abdominal aortic aneurysm (AAA) is an established indicator of surgical success. However, even with a completely excluded aneurysm, the degree of aortic sac regression may vary. This study evaluates the relationship between aneurysm sac regression after EVAR and the presence of morphological features in the thoracic aorta that can be associated with a subclinical aortic dissection, termed dissection morphology in this study. Patients who underwent EVAR to repair an infrarenal aortic aneurysm at Mount Sinai Hospital between 1996 and 2017 with a postoperative CT scan and a 3-year follow-up scan available for analysis were included in the study. Patients with a type I or type III endoleak were not included. The thoracic aorta was evaluated for dissection morphology on CT scan, which included the presence of aortic dissection, penetrating aortic ulcers, and intramural hematomas. AAA sac regression after EVAR was compared between patients with dissection morphology (n=157) and patients without those characteristics (n=141). An independent investigator performed the CT analysis and was blinded to the degree of sac regression. Demographics and comorbid clinical conditions were compared between patients with and without dissection morphology. There were no significant differences in age, gender, smoking habits, or cardiovascular conditions. The median AAA diameter after EVAR, over the course of the study, in patients with dissection morphology decreased by 11.30mm (-17.20, -3.60) compared to a median change of 0.30mm (-8.60, 8.60) in patients without dissection morphology features (p<0.001). Patients with dissection morphology also had fewer type II endoleaks in postoperative follow-up scans (22.9% vs. 53.9%, p<0.001). Additionally, patients with dissection morphology had longer EVAR operative times (192.00min [167.25, 230.00] vs.174.00min [150.00, 215.00], p=0.004). AAA-related mortality after 3 years was not significantly different between the 2 groups (p=1.0). The presence of imaging features consistent with dissection morphology in the thoracic aorta correlated with greater AAA sac regression and fewer type II endoleaks after EVAR. Assessing these imaging features in patients undergoing EVAR may be useful in understanding aneurysm behavior in terms of aneurysm growth, risk of rupture, and outcomes following endovascular surgery. Identifying differential rates of aneurysm sac regression may have implications regarding the role of subclinical dissections in the etiology of AAA development.

Is Abdominal Aortic Aneurysm Behavior after Endovascular Repair Associated with Aneurysm Wall Density on Computed Tomography Angiography?

Background and objectives: Abdominal aortic aneurysm (AAA) growth is unpredictable after the endovascular aneurysm repair (EVAR). Continuing aortic wall degradation and weakening due to hypoxia may have a role in post-EVAR aneurysm sac growth. We aimed to assess the association of aortic wall density on computed tomography angiography (CTA) with aneurysm growth following EVAR. Materials and Methods: A total of 78 patients were included in the study. The control group consisted of 39 randomly assigned patients without aortic pathology. Post-EVAR aneurysm sac volumes on CTA were measured twice during the follow-up period to estimate aneurysm sac behavior. A maximum AAA sac diameter, aortic wall and lumen densities in Hounsfield units (HU) on CTA were measured. A relative aortic wall density (the ratio of aortic wall to lumen densities) was calculated. A statistical data analysis was performed using standard methods. Results: An increase in the AAA sac volume was observed in 12 (30.8%) cases. Median relative aortic wall density on CTA scores in both the patient and the control group at the level of the diaphragm were similar: 0.15 (interquartile range (IQR), 0.11–0.18) and 0.16 (IQR 0.11–0.18), p = 0.5378, respectively. The median (IQR) relative aortic wall density score at the level of the maximum AAA diameter in the patient group was lower than at the level below renal arteries in the control group: 0.10 (0.07–0.12) and 0.17 (0.12–0.23), p < 0.0001, respectively. The median (IQR) relative growing AAA sac wall density score was lower than a relative stable/shrinking AAA sac wall density score: 0.09 (0.06–0.10) and 0.11 (0.09–0.13), p = 0.0096, respectively. Conclusions: A lower aortic aneurysm wall density on CTA may be associated with AAA growth after EVAR.

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

ObjectiveEndovascular 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. MethodsAll 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. ResultsThe 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). ConclusionsPatients 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.

Abdominal Aortic Disease: A Multicase Review

Abdominal aortic disease affects more than 3 million people per year. For vascular sonographers, imaging aortic disease can become routine. Therefore, it is necessary to expand the knowledge that we have of aortic disease, diagnosis, and treatment. We present 4 cases with new or worsening conditions diagnosed by duplex ultrasound (DUS). Our first case is a 79-year-old woman returning for surveillance of an endovascular aneurysm repair (EVAR). The DUS findings reveal an increasing abdominal aortic aneurysm (AAA) sac, with evidence of flow originating from an incomplete seal at the attachment suggesting type I endoleak. Next, is a 56-year-old man returning 1 month after type A dissection repair, now presenting with unilateral claudication. The DUS findings of the left lower extremity demonstrated an early systolic deceleration waveform, suggesting more proximal disease. Upon further imaging, an abdominal aortic dissection was identified terminating into the left internal iliac artery, causing the true lumen to be compressed. The third case was a 75-year-old man returning for follow-up of an EVAR and iliac repair. The DUS findings show an increase in iliac artery sac size and anechoic area that was filled with color Doppler flow. These findings are suggestive of type I endoleak involving the distal attachment. The last case is a 56-year-old man returning for EVAR and iliac artery repair surveillance. The common iliac artery aneurysm sac had increased in diameter and length. The distal attachment of the left iliac extension cuff terminated within the aneurysm sac, causing a type I endoleak. Accurate DUS diagnosis of aortic disease is crucial for patient care. Meticulous analysis of the vessels and surrounding structures can make a difference in diagnostic outcomes. Vascular sonographers should continually review and revise vascular laboratory protocols to increase their diagnostic accuracy and improve patient care. It is important to extend the vascular laboratory protocols when complex cases arise to better demonstrate complicated diagnoses and challenging anatomy.

Aortic sac enlargement after endovascular aneurysm repair: volume-related changes and the impact of intraluminal thrombus.

PurposeAbdominal aortic aneurysm (AAA) growth after endovascular aneurysm repair (EVAR) is still unpredictable. The issue of optimal frequency of computed tomography angiography for surveillance and its measurement method accuracy remain unclear. We aimed to assess the value of abdominal aneurysm sac volume measurement for detecting expansions and the association of preprocedural intraluminal thrombus (ILT) volume with aneurysm sac growth following EVAR.Material and methodsA total of 107 patients underwent elective EVAR. Inclusion criteria provided a cohort of 39 patients. Changes of postoperative maximum aneurysm sac diameter and AAA volume were calculated. Volumetric AAA changes and demographic data of the cases with clinically irrelevant AAA diameter enlargement were evaluated. Preoperative ILT volumes were collected. ILT and AAA sac volume ratio was calculated. Statistical data analysis was performed using standard methods.ResultsThe mean changes of maximum AAA diameter and volume in percentage after EVAR were –5.08 ± 8.20 mm and –13.39 ± 23.32%, respectively. A moderate positive linear correlation between those changes was found (R 2 = 0.731; p < 0.0001). The mean relative AAA volume increase in cases without clinically relevant diameter enlargement was 11.50 ± 8.27%. The means of ILT and AAA sac ratios were 0.59 ± 0.17 and 0.52 ± 1.8 in growing AAA sac and in stable or shrinking AAA sac groups, respectively (p = 0.308).ConclusionsVolumetric AAA measurement may be useful as an additional method to diameter measurement after EVAR to identify clinically relevant sac growth. Preoperative volume of ILT may not significantly affect the growth rate of AAA after EVAR.

Type II endoleak model creation and intraoperative aneurysmal sac embolization with n-butyl cyanoacrylate-lipiodol-ethanol mixture (NLE) in swine.

The purpose of this study was to evaluate the feasibility of type II endoleak model creation and efficacy of intraoperative aneurysmal sac embolization using n-butyl-2-cyanoacrylate-lipiodol-ethanol mixture (NLE) for type II endoleak in swine. In six swine (mean body weight 53.5 kg), abdominal aortic aneurysm (AAA) was created and then end-to-side anastomosis between the left renal artery and AAA sac was performed. And then, endovascular abdominal aortic aneurysm repair (EVAR) was performed, leading to creation of a type II endoleak model. As control group, EVAR without sac embolization was performed in two swine. In four swine, AAA sac was embolized using NLE immediately after EVAR via the microcatheter placed in AAA sac (NLE embolization group). Follow-up aortography was performed immediately and three days after the procedure, and then the aneurysms were extracted. The AAA sac and type II endoleak model were successfully created in all cases. In control group, type II endoleak persisted three days after the procedure. In NLE embolization group, endoleak disappeared immediately and three days after the procedure. In NLE embolization group, AAA sac was occupied with thrombus and embolic material. Inflammatory changes were recognized in aneurysmal sac wall in NLE embolization group. This experimental study suggests that creation of a type II endoleak model in swine is feasible and that intraoperative AAA sac embolization with NLE during EVAR might reduce the occurrence of type II endoleak.

TCT-286 Novel Approach for Treatment of Aortic Stent Graft Endoleak: a Preclinical Feasibility Study of Catheter-Delivered Expandable Foam

Endoleak is defined as persistent flow of blood into the abdominal aortic aneurysm (AAA) sac after endograft placement and signifies a failure to completely exclude the aneurysm. It is present in 20-50% of patients treated with endograft implantation and is associated with continued risk for

Invited commentary

In light of the current enthusiasm for the expanded use of branched and fenestrated endovascular aneurysm repair (F/B-EVAR) of complex aortic aneurysms, we are fortunate that Dr Schanzer and his colleagues have given us some insight into the high reintervention rate of patients after F/B-EVAR. The 26% need for at least one re intervention is probably understated in this study, given the inclusion of a small number of iliac branched devices and the significant number of commercially available Cook Zenith fenestrated renal branch devices (arguably the low-hanging fruit of F/B-EVAR grafts). Furthermore, the authors can expect even further reinterventions, given the relatively short-term follow-up of 25 months and the fact that reintervention rates seem to increase rather than to decrease over time. Several points are worth emphasizing. First of all, it is reassuring to see that the great majority of problems requiring reintervention after F/B-EVAR can be successfully managed (most often through an endovascular approach). Second, these devices were placed under the auspices of a physician-sponsored investigational device exemption trial. As such, patients were carefully selected to ensure anatomic suitability for a successful repair. This senior author knows better than most the poor results that can result when the limits of anatomic acceptability are stretched to expand the application of endovascular technology.1Schanzer A. Greenberg R.K. Hevelone N. Robinson W.P. Eslami M.H. Goldberg R.J. et al.Predictors of abdominal aortic aneurysm sac enlargement after endovascular repair.Circulation. 2011; 123: 2848-2855Crossref PubMed Scopus (576) Google Scholar Analogous to the application of EVAR, we can anticipate even higher rates of failure, reintervention, and poor outcomes as this technology proliferates to less selective surgeons. Third, the authors demonstrate a significantly higher reintervention rate in physician-modified endografts (PMEGs) compared with company-manufactured devices (CMDs). They note that there is still a role for PMEGs in urgent cases. By inference, CMDs are preferred for elective cases. Given that CMDs are restricted to only a small number of centers nationwide, the implications for surgeons using PMEGs for elective repair are important. Finally, patients with complex aneurysms repaired with F/B-EVAR should be considered to have a chronic disease with vigilant continued follow-up and anticipated reinterventions. Reinterventions after fenestrated or branched endovascular aortic aneurysm repairJournal of Vascular SurgeryVol. 68Issue 3PreviewReinterventions after fenestrated or branched endovascular aneurysm repair (F/B-EVAR) are sometimes necessary to maintain aneurysm exclusion or endograft and target artery patency. These reinterventions are nontrivial, potentially associated with morbidity, mortality, and resource utilization. Whereas rates, types, and outcomes of reintervention after infrarenal EVAR have been well described, they have not been well described for F/B-EVAR. We sought to characterize the morbidity, mortality, and resource utilization due to reinterventions after F/B-EVAR. Full-Text PDF Open Archive