Significance of endoleaks after endovascular repair of abdominal aortic aneurysms: The EUROSTAR experience

Total realignment of multibranch stent graft using redo branch-in-branch endovascular repair for occult endoleak with rapid aneurysm sac expansion

Occult endoleaks can pose a diagnostic and treatment challenge. These endoleaks are not effectively identified by multiphase computed tomography angiography, magnetic resonance angiography, or contrast-enhanced ultrasound. Possible causes are small fabric tears and slow-flow, dynamic, or positional endoleaks. We describe a patient with rapid aneurysm sac expansion and disseminated intravascular coagulopathy 46 months after four-vessel branched physician-modified endograft repair of a ruptured extent III thoracoabdominal aneurysm. Imaging failed to demonstrate an endoleak but identified fresh blood products within the sac. The patient underwent total realignment using branch-in-branch repair with a physician-modified endograft. Repeated imaging 25 days postoperatively revealed decrease in aneurysm diameter by 10 mm.

Paradigm shifts in abdominal aortic aneurysm management based on vascular registries

Abdominal aortic aneurysm (AAA) is a relatively common and potentially fatal disease. The management of AAA has undergone extensive changes in the last two decades. High quality vascular surgical registries were established early and have been found to be instrumental in the evaluation and monitoring of these changes, most notably the wide implementation of minimally invasive endovascular surgical technology. Trends over the years showed the increased use of endovascular aneurysm repair (EVAR) over open repair, the decreasing perioperative adverse outcomes and the early survival advantage of EVAR. Also, data from the early EVAR years changed the views on endoleak management and showed the importance of tracking the implementation of new techniques. Registry data complemented the randomized trials performed in aortic surgery by showing the high rate of laparotomy-related reinterventions after open repair. Also, they are an essential tool for the understanding of outcomes in a broad patient population, evaluating the generalizability of findings from randomized trials and analysing changes over time. By using large-scale data over longer periods of time, the importance of centralization of care to high-volume centres was shown, particularly for open repair. Additionally, large-scale databases can offer an opportunity to assess practice and outcomes in patient subgroups (e.g. treatment of AAA in women and the elderly) as well as in rare aortic pathologies. In this review article, we point out the most important paradigm shifts in AAA management based on vascular registry data.

Outcomes of type Ia endoleaks after endovascular repair of the proximal aorta

OBJECTIVE

Thoracic endovascular aortic repair (TEVAR) can be complicated by a type Ia endoleak. However, its natural history remains unclear. This report describes the natural history and midterm outcome of conservatively treated type Ia endoleaks in the proximal aorta.

METHODS

Between 2007 and 2015, 395 patients underwent TEVAR at our institution. Only TEVARs landing proximally at landing zones 0, 1, and 2 were included (221/395). Type Ia endoleak's flow was classified as "fast" or "slow" based on the time needed to visualize the aneurysmal sac during arteriogram.

RESULTS

The median follow-up was 4.1 years. Aortic dissection, thoracic aortic aneurysm, and traumatic aortic injury were the most common indications for TEVAR; the incidence of type Ia endoleak was not statistically different. Forty-seven patients (21.3%) had a type Ia endoleak. TEVAR landing proximally at zone 1 increased the odds of developing a type Ia endoleak (odds ratio, 2.8; 95% confidence interval, 1.3-5.9; P = .0072). The 30-day mortality and the overall survival was not influenced by the development of immediate-type Ia endoleak. In 34 (72.3%) patients, the endoleak resolved spontaneously. Ninety-four percent of these patients had a SlowE (n = 32/34). All of spontaneous resolutions occurred before the end of the first postoperative year.

CONCLUSIONS

SlowE tends to resolve within 1 year after TEVAR. Initial conservative treatment seems to be a reasonable approach in patients with SlowE.

Cost-effectiveness of contrast-enhanced ultrasound for the detection of endovascular aneurysm repair-related endoleaks requiring treatment

OBJECTIVE

Follow-up after endovascular aneurysm repair is necessary to detect potentially life-threatening complications such as endoleaks. Computed tomography angiography (CTA) or magnetic resonance angiography (MRA) is often used as standard of care for follow-up. Contrast-enhanced ultrasound (CEUS) has been shown to be a viable and fast real-time nonionizing imaging modality with equivalent diagnostic accuracy while also being superior to color Doppler ultrasound. The aim of this cost-utility analysis was to evaluate the cost-effectiveness of this imaging method in comparison to others for the evaluation of endoleaks requiring treatment.

METHODS

A decision model based on Markov simulations estimated lifetime costs and quality-adjusted life years (QALYs) associated with CTA, MRA, CEUS, and color Doppler ultrasound. Model input parameters were obtained from recent literature. The applied sensitivity and specificity values amounted to 90.5% and 100.0% for CTA, 96.0% and 100.0% for MRA, 94.0% and 95.0% for CEUS, and 82.0% and 93.0% for color Doppler ultrasound. Probabilistic and deterministic sensitivity analysis was performed to estimate uncertainty of model results. To evaluate cost-effectiveness, incremental cost-effectiveness ratios were reported as a measure representing the economic value of a strategy compared with an alternative. The willingness to pay was set to $100,000/QALY.

RESULTS

In the base-case scenario for a willingness to pay of $100,000 per QALY, CEUS was the most cost-effective of the four diagnostic strategies with estimated costs of $17,383 and effectiveness of 9.770 QALYs. CTA was estimated to result in lifetime costs of $17,679 with an expected effectiveness of 9.768 QALYs, whereas color Doppler ultrasound showed expected costs of $17,287 with 9.763 QALYs. Expected costs and effectiveness of MRA amounted to $17,945 and 9.771 QALYs each. Base-case estimates of the incremental cost-effectiveness ratios for CEUS vs color Doppler ultrasound equaled $14,173.52/QALY.

CONCLUSIONS

CEUS is a cost-effective imaging method for the evaluation of therapy-requiring endoleaks in endovascular aneurysm repair surveillance.

Immediate and 1-year success rate of type 2 endoleak treatment using three-dimensional image fusion guidance

PURPOSE

To retrospectively assess immediate and 1-year success rate of type 2 endoleak (T2E) treatment with ethylene-vinyl-alcohol-polymer using three-dimensional (3D) image fusion guidance with cone beam computed tomography via trans-arterial embolization (TAE) or direct percutaneous sac injection (DPSI).

MATERIALS AND METHODS

A total of 37 patients with T2E who were treated either using TAE (34/37; 92%) or DPSI (9/37; 8%) were included. There were 34 men and 3 women with a mean age of 86±9 (SD) years (range: 67-104years). Mean aneurysm diameter was 67±14 (SD) mm (range: 42-101mm) at pre-procedure evaluation. Immediate success was complete embolization of the sac and feeding artery. 1-year success was reduction or stability of the aneurysmal sac diameter based on pre-procedure and 12-month follow-up examinations. Safety (treatment-related complications), patient demographics, duration of procedure and contrast volume were reported.

RESULTS

Immediate and 1-year successful outcomes were reported in 94% (n=32) and 88% (n=28) of patients after TAE and 100% (n=9) and 89% (n=8) after DPSI. T2E treatments were immediately successful for 95% of the procedures (41/43) and for 88% (36/41) at 1year. Overall, T2E treatment was effective in 33 patients (89%). No major complications occurred. Mean procedure time and contrast volume were significantly different between the 2 techniques with respectively 87±16 (SD) min (range: 65-120min) and 75±26 (SD) mL (range: 40-130mL) for TAE and 32±10 (SD) min (range: 20-50min) (P<0.01) and 6±6 (SD) mL (range: 2-22mL) (P<0.01) for DPSI. Mean aneurysm diameter at 1-year was 68±17 (SD) mm (range: 43-101mm). No significant differences in the pre-procedure sac diameter were found at long-term follow-up between patients without T2E and those with persistent T2E (P=0.1) in the successful embolization group (n=33).

CONCLUSION

TAE or DPSI treatments of T2E with ethylene-vinyl-alcohol-polymer using 3D-image fusion guidance were immediately successful for 95% of the procedures and remained effective for 88%. Longer follow-up is necessary to assess sac stability in the case of persistent endoleak.

Multicentre randomised controlled trial to evaluate the efficacy of pre-emptive inferior mesenteric artery embolisation during endovascular aortic aneurysm repair on aneurysm sac change: protocol of Clarify IMA study

INTRODUCTION

Type II endoleak (EL) is frequently seen after endovascular aneurysm repair (EVAR) for abdominal aortic aneurysm (AAA) and is often considered responsible for aneurysm sac enlargement if it persists. In order to reduce type II EL and consequent sac enlargement, pre-emptive embolisation of the inferior mesenteric artery (IMA), which is a main source for persistent type II EL, has been introduced in many vascular centres. At present, there is a lack of robust evidence to support the efficacy of pre-emptive embolisation of IMA on reduction of persistent type II EL with subsequent sac shrinkage.

METHOD AND ANALYSIS

This multicentre, randomised controlled trial will recruit 200 patients who have fusiform AAA ≥50 mm/rapidly enlarging fusiform AAA, with patent IMA, and randomly allocate them either to a pre-emptive IMA embolisation group or non-embolisation control group in a ratio of 1:1. The primary endpoint is the difference of aneurysm sac volume change assessed by CT scans between the pre-emptive IMA embolisation group and the control group at 12 months after EVAR. The secondary endpoints are defined as change of aneurysm sac volume in both groups at 6 and 24 months, freedom from sac enlargement at 12 and 24 months after EVAR, prevalence of type II EL at 1, 6, 12 and 24 months evaluated by contrast-enhanced CT, reintervention rate, aneurysm related mortality, overall survival, perioperative morbidity, volume of contrast media used during EVAR and dosage of radiation.

ETHICS AND DISSEMINATION

The protocol has been reviewed and approved by the ethics committee of Nara Medical University (No. 2113). The findings of this study will be communicated to healthcare professionals, participants and the public through peer-reviewed publications, scientific conferences and the University Hospital Medical Information Network Clinical Trials Registry home page.

TRIAL REGISTRATION NUMBER

UMIN000035502.

Similar 5-year outcomes between female and male patients undergoing elective endovascular abdominal aortic aneurysm repair with the Ovation stent graft

OBJECTIVE

Female patients undergoing endovascular aneurysm repair (EVAR) for infrarenal abdominal aortic aneurysms present with more challenging anatomy and historically have worse outcomes compared with men. The Ovation Abdominal Stent Graft platform (Endologix, Irving, Calif) contains a polymer-filled proximal sealing ring and has a low-profile delivery system, potentially beneficial in female patients. We therefore investigated differences in long-term outcomes between men and women treated with this device.

METHODS

We used data collected prospectively in the Effectiveness of Custom Seal with Ovation: Review of the Evidence (ENCORE) database, comprising five trials and the European Post-Market Registry. Anatomic characteristics of the proximal aneurysm neck and iliac arteries were compared between male and female patients. Outcomes were 5-year freedom from type IA and type I/III endoleaks, abdominal aortic aneurysm-related reinterventions, and overall survival. We used Kaplan-Meier analysis to estimate survival proportions and tested univariate differences in survival using log-rank tests. Cox proportional hazards modeling was used to adjust for baseline differences.

RESULTS

We identified 1045 (81%) male and 251 (19%) female patients undergoing EVAR. Female patients were older (mean age, 75 ± 8.4 years vs 73 ± 8.1 years; P < .006). Aneurysm diameter (52 ± 7.5 mm vs 55 ± 9.2 mm; P < .001) and proximal neck diameter (21 ± 3.3 mm vs 23 ± 2.9 mm; P < .001) were smaller in female patients, but adjusted for body surface area, female patients had relatively larger aneurysms and aneurysm necks. Furthermore, female patients presented with shorter proximal necks, smaller iliac artery diameters, more angulated necks, and higher rates of reverse-tapered necks. Five-year freedom from type IA endoleak was similar between men and women (97% vs 96%; P = .38), as was freedom from type I/III endoleaks (91% vs 94%; P = .37) and reinterventions (91% vs 93%; P = .67). Five-year survival was 81% for female patients, similar to the 79% in male patients (P = .55), with one aneurysm-related death in female patients (0.4%) and five in male patients (0.8%; P = .76). Risk-adjusted analyses showed no association between sex and type IA endoleak (hazard ratio [HR], 1.4; 95% confidence interval [CI], 0.6-3.1; P = .41), type I/III endoleak (HR, 1.4; 95% CI, 0.7-2.8; P = .33), reintervention (HR, 1.0; 95% CI, 0.6-2.0; P = .77), and overall mortality (HR, 0.7; 95% CI, 0.4-1.1; P = .14).

CONCLUSIONS

Female patients undergoing EVAR with the Ovation platform presented with substantially more adverse proximal neck characteristics. Despite these differences, 5-year freedom from endoleaks and overall survival did not differ between sexes.

Outcomes after treatment of complex aortic abdominal aneurysms with the fenestrated Anaconda endograft

OBJECTIVE

To date, information on the fenestrated Anaconda endograft is limited to case series with a small sample size. This study was performed to assess the technical and clinical outcome of this device in a large international case series.

METHODS

All worldwide centers having treated more than 15 complex abdominal aortic aneurysms (AAA) or type IV thoracoabdominal aortic aneurysm patients with the fenestrated Anaconda endograft were approached. Main outcome parameters were procedural technical success, postoperative and follow-up clinical outcome for endoleaks, target vessel patency, reintervention rate, and patient survival.

RESULTS

Three hundred thirty-five consecutive cases treated between June 2010 and May 2018 in 11 sites were included. Patients were treated for a short neck infrarenal (n = 98), juxtarenal (n = 191), suprarenal AAA (n = 27), or type IV thoracoabdominal aortic aneurysm (n = 19). Mean age was 73.6 ± 4.6 years (292 male). Endografts contained a total of 920 fenestrations, with a mean of 2.7 ± 0.8 fenestrations per case. Technical success was 88.4% (primary, 82.7%; assisted primary 5.7%). In 6.9% of cases, a procedural type IA endoleak was observed, spontaneously disappearing in 82.6% during early follow-up. The development of a type IA endoleak was associated with greater neck angulation (odds ratio [OR], 0.94; P = .01), three fenestrations (OR, 42.7; P = .01) and the presence of augmented proximal rings (OR, 0.17; P = .03). Median follow-up was 1.2 years (interquartile range, 0.4-2.6). The mean estimated glomerular filtration rate deteriorated from 67.6 ± 19.3 mL/min/1.73 m² preoperatively to 59.3 ± 22.7 mL/min/1.73 m² at latest follow-up (P = .00). The freedom from AAA growth were 97.9 ± 0.9% (n = 190) and 86.4 ± 3.0% (n = 68), with a freedom from AAA rupture of 99.7 ± 0.3% (n = 191) and 99.1 ± 0.7% (n = 68), at 1 and 3 years, respectively. The endoleak-free survival, excluding spontaneously resolved procedural endoleaks, at 1 and 3 years was 73.4 ± 2.6 (n = 143) and 65.6 ± 3.4% (n = 45), respectively. The target vessel patency at one and three years were 96.4 ± 0.7% (n = 493) and 92.7 ± 1.4% (n = 156), respectively. A total of 75 reinterventions were done in 64 cases (19.1%), of which 25 cases for an endoleak. The reintervention-free survival at 1 and 3 years were 83.6 ± 2.2% (n = 190) and 71.0 ± 3.7% (n = 68), respectively. No deaths during procedure, extending within 24 hours postoperatively, were observed. Within 30 days 14 patients (4.2%) died and during follow-up another 39 patients (11.6%) died. Three deaths were considered AAA related (one rupture, one endograft infection, and one bilateral renal artery occlusion). The estimated cumulative survival at 1 and 3 years were 89.8 ± 1.8% (n = 191) and 79.2 ± 3.0% (n = 68), respectively.

CONCLUSIONS

The custom-made fenestrated Anaconda endograft is a valuable option for the treatment of a complex AAA. A procedural type IA endoleak is seen relatively frequently, but spontaneously resolves in most cases.

Velocities of type II endoleaks on Doppler ultrasonography predict outcome

OBJECTIVE

We sought to determine whether flow velocities measured using Doppler ultrasonography after endovascular aortic aneurysm repair (EVAR) can predict for resolution of type II endoleaks without intervention. We also assessed the relationship of the flow velocities to sac growth and the need for intervention. We hypothesized that hemodynamic properties suggesting low flow velocity would predict for resolution of type II endoleaks.

METHODS

The data from 23 patients with type II endoleaks identified on Doppler ultrasonography after EVAR from January 2014 to December 2017 were retrospectively analyzed. The 23 patients with type II endoleaks were split into two groups. Group 1 included the 13 patients with resolved endoleaks or shrinking sac size and group 2, the 10 patients with an increasing sac size or those requiring intervention to seal the endoleak because of an increased sac size. We analyzed the velocities of the endoleak nidus.

RESULTS

Doppler ultrasound velocities were significantly lower in patients with resolved type II endoleaks and those with a shrinking aneurysm sac size compared with those demonstrating an increase in aneurysm sac size (42.6 ± 25.2 cm/s vs 219.5 ± 84.1 cm/s; P < .0001). Of the 10 patients in group 2, nine had required intervention with either translumbar embolization or transarterial embolization, with only two experiencing complete resolution of the type II endoleak, despite the intervention. All patients in group 2 had had ≥1 duplex ultrasound scan with endoleak nidus velocities >100 cm/s. In contrast, no patient in group 1 had had any duplex ultrasound scan with endoleak nidus velocities >100 cm/s.

CONCLUSIONS

The Doppler ultrasound velocities of type II endoleaks might be able to predict for spontaneous resolution of type II endoleaks or increased sac growth. Type II endoleaks on Doppler ultrasonography with endoleak nidus velocities >100 cm/s can persistent, even with attempted treatment.

Optimizing Surveillance and Re-intervention Strategy Following Elective Endovascular Repair of Abdominal Aortic Aneurysms

BACKGROUND

EVAR for abdominal aortic aneurysm has an initial survival advantage over OR, but more frequent complications increase costs and long-term aneurysm-related mortality. Randomized controlled trials of EVAR versus OR have shown EVAR is not cost-effective over a patient's lifetime. However, in the EVAR-1 trial, postoperative surveillance may have been sub-optimal, as the importance of sac growth as a predictor of graft failure was overlooked.

METHODS

Real-world data informed a discrete event simulation model of postoperative outcomes following EVAR. Outcomes observed EVAR-1 were compared with those from 5 alternative postoperative surveillance and re-intervention strategies. Key events, quality-adjusted life years and costs were predicted. The impact of using complication and rupture rates from more recent devices, imaging and re-intervention methods was also explored.

RESULTS

Compared with observed EVAR-1 outcomes, modeling full adherence to the EVAR-1 scan protocol reduced abdominal aortic aneurysm (AAA) deaths by 3% and increased elective re-interventions by 44%. European Society re-intervention guidelines provided the most clinically effective strategy, with an 8% reduction in AAA deaths, but a 52% increase in elective re-interventions. The cheapest and most cost-effective strategy used lifetime annual ultrasound in primary care with confirmatory computed tomography if necessary, and reduced AAA-related deaths by 5%. Using contemporary rates for complications and rupture did not alter these conclusions.

CONCLUSIONS

All alternative strategies improved clinical benefits compared with the EVAR-1 trial. Further work is needed regarding the cost and accuracy of primary care ultrasound, and the potential impact of these strategies in the comparison with OR.

Five-year results of endovascular abdominal aortic aneurysm repair with the Ovation abdominal stent graft

OBJECTIVE

Endovascular abdominal aortic aneurysm repair (EVAR) has been rigorously compared with open repair for the treatment of abdominal aortic aneurysms in randomized trials and observational studies, but a comparison of individual devices is lacking, and single-device registries and trials are limited by small sample size. Here we report a descriptive analysis of the Effectiveness of Custom Seal with Ovation: Review of the Evidence (ENCORE) database, pooled results of multiple studies evaluating the midterm results of EVAR with the Ovation Abdominal Stent Graft Platform.

METHODS

This is a retrospective analysis of the ENCORE database, a cohort of patients undergoing EVAR with the Ovation platform composed of pooled, prospectively collected data from 1296 patients from five clinical trials and the prospectively maintained European Union Post-Market Registry. The primary outcomes were 5-year rates of type IA and type I or III endoleak. Secondary outcomes included were 30-day mortality, 30-day major adverse event, technical success (successful deployment of the aortic body and iliac limbs), as well as 5-year survival, and freedom from aneurysm-related mortality, type II endoleak, device-related intervention, aneurysm rupture, sac expansion, and conversion to open repair.

RESULTS

A total of 1296 patients were included in the analysis. The average age was 73 ± 8 years and 81% of patients were male. Fifty percent of patients had complex aortic anatomy, (neck length <10 mm, neck diameter >28 mm, neck angle >60°, reverse neck taper >10%, distal common iliac artery diameter <10 mm, or external iliac artery diameter <6 mm). Technical success was 99.7%. Thirty-day mortality was 0.3%, 30-day rate of major adverse event was 1.6%, and polymer leak rate was 0.2%. Freedom from type IA endoleak at 1, 3, and 5 years was 97.6%, 97.1%, and 95.8%, respectively; type I or III endoleak at 1, 3, and 5 years was 96.9%, 95.7%, and 94.0%, respectively. Freedom from device-related reintervention at 1, 3, and 5 years was 96.2%, 94.4%, and 92.4% and primary freedom from sac expansion was 97.0% at 1 year, 90.3% at 3 years, and 84.9% at 5 years. Freedom from all-cause mortality and aneurysm-related mortality at 5 years were 78.9% and 99.3%, respectively.

CONCLUSIONS

This analysis of the ENCORE database demonstrates that EVAR with the Ovation platform has favorable midterm durability evidenced by successful aneurysm exclusion and 5-year freedom from aneurysm-related mortality.

Nonsteroidal anti-inflammatory drug use is a risk factor for early Type II endoleak after endovascular abdominal aortic repair

Objectives

Type II endoleak is a problem after endovascular abdominal aneurysm repair. Preoperative risk factors for Type II endoleak include anatomical factors in the lumbar artery and inferior mesenteric artery; however, preventable postoperative risk factors are unknown. Postimplantation syndrome is associated with lower incidence of Type II endoleak. Therefore, we focused on inflammation, and our aim was to investigate nonsteroidal anti-inflammatory drugs as a postoperative risk factor for Type II endoleak.

Methods

This was a retrospective study of patients with aortic aneurysm who underwent endovascular aneurism repair at the Department of Cardiovascular Surgery, Beppu Medical Center, Oita, Japan, from January 2011 to August 2018. Clinical characteristics were retrieved from patients’ medical records and included age, sex, body mass index, smoking history, comorbidities, treatment devices, medications, and perioperative information, including postimplantation syndrome. Postimplantation syndrome was defined as body temperature >38.5°C with 12,000/dL white blood cells or >10.0 mg/dL C-reactive protein. The primary outcome was the presence or absence of Type II endoleak assessed on the first postoperative enhanced computed tomography scan. Risk factors for Type II endoleak were assessed. Results and conclusions: Of the eligible 84 patients, 20 (24%) had Type II endoleak identified in the first enhanced computed tomographic scans after endovascular aneurism repair. Nonsteroidal anti-inflammatory drug use (odds ratio (OR): 21.2; 95% confidence interval (95% CI): 1.5–308.4; P = 0.026), cerebrovascular disease (OR: 7.27; 95% CI: 1.06–49.99; P = 0.044), and body mass index <22 kg/m2 (OR: 17.3; 95% CI: 2.1–141.8; P = 0.008) were independent risk factors for Type II endoleak after endovascular aneurism repair. Comparing the rate of Type II endoleak among patients who did not receive nonsteroidal anti-inflammatory drugs within 24 h after endovascular aneurism repair, patients who first used nonsteroidal anti-inflammatory drugs 12–24 h after endovascular aneurism repair, and those who received nonsteroidal anti-inflammatory drugs within 12 h after endovascular aneurism repair, we found a significant difference among the groups (4%, 18%, 45%, respectively; P = 0.001). Nonsteroidal anti-inflammatory drug use within 24 h after endovascular aneurism repair is a risk factor for Type II endoleak. We should know nonsteroidal anti-inflammatory drugs within 24 h after endovascular aneurism repair can be a risk of Type II endoleak.

Higher preprocedural fibrinogen levels are associated with aneurysm sac regression after EVAR

Summary. Background: The aim of our study was to determine the diameter of the aneurysm sac 24 months after endovascular abdominal aortic aneurysm repair (EVAR); to identify factors associated with sac regression, and to determine the impact of sac regression on all-cause mortality during long-term follow-up. Patients and methods: We conducted a retrospective review of prospectively collected data from patients treated with EVAR between January, 2010 and July, 2016. Sac regression was defined as at least 5 mm decrease in aneurysm diameter in relation to the preprocedural diameter seen on computed tomography angiography. Sociodemographic information, comorbidities, treatment, laboratory parameters, selected anatomical and genetic factors were all analysed to determine their impact on sac regression. Results: During the study period, 124 patients with mean age of 71.2 ± 7.2 years met the inclusion criteria. Sac regression was found in 45.2% of patients. Higher preprocedural fibrinogen was found in patients with sac regression in comparison with patients with stable sac or sac expansion (3.84 g/l vs 3.47 g/l; p = 0.028). In multivariate analysis after adjustment for age, hypertension, sex, smoking, dyslipidaemia, volume and percentage of intraluminal thrombus higher fibrinogen was associated with an increased probability of sac regression (OR 2.47; 95% CI 1.29–4.72; p = 0.006). Persistent type II endoleak was associated with significantly lower probability of sac regression in univariate and multivariate analysis after adjustment for age, hypertension, sex, smoking and dyslipidaemia (OR 0.26; 95% CI 0.10–0.66; p = 0.004). Higher age was a significant predictor of sac regression in multivariate analysis after adjustment for hypertension, sex, smoking and dyslipidaemia (OR 1.07; 95% CI 1.02–1.14; p = 0.012). No difference was found between patient subgroups with and without sac regression in all-cause mortality during follow-up. Conclusions: Higher preprocedural fibrinogen, absence of persistent type II endoleak and higher age were predictive factors of aneurysm sac regression post-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.

Usefulness of Abdominal Duplex Ultrasound for Detecting Endoleaks after Endovascular Aneurysm Repair

Objective: The usefulness of abdominal duplex ultrasound (DUS) for the detection of endoleaks after endovascular aneurysm repair (EVAR) was evaluated. Materials and Methods: Among 286 patients who underwent EVAR between September 2007 and July 2017, 241 patients were followed up using abdominal DUS. Endoleaks were detected in 74 patients (31%), who were divided into enlarged and nonenlarged sac groups. Endoleak velocities and widths were measured using abdominal DUS every 6 months after EVAR and were compared between the 2 groups. Results: The aneurysm diameter in the nonenlarged sac group was 54.4±8.7 mm in the final follow-up. None of the patients in the nonenlarged sac group were subjected to reintervention, whereas all patients in the enlarged sac group were subjected to reintervention. The aneurysm diameter in the enlarged sac group was 62.8±8.8 mm at the time of reintervention, and the maximum endoleak flow velocities and endoleak widths were significantly higher in the enlarged sac group than in the nonenlarged sac group (p<0.05). The cutoff values on receiver operating characteristics curves for endoleak velocity and width were 83.4 cm/s and 4.0 mm, respectively. Conclusion: Follow-ups using abdominal DUS are useful after EVAR. Endoleak velocity and width measurements are important, and reintervention may be needed when these measurements exceed their cutoff values.

Effectiveness of Intra-Arterial Aneurysm Sac Embolization for Type Ia Endoleak after Endovascular Aneurysm Repair

PURPOSE

To evaluate the effectiveness and durability of intra-arterial aneurysm sac embolization for the treatment of type Ia endoleak after endovascular aneurysm repair (EVAR).

MATERIALS AND METHODS

From February 2011 to December 2016, 22 patients underwent embolization of a type Ia endoleak after EVAR. Four patients (18%) were treated during the index EVAR and 18 (82%) in follow-up. Five patients (23%) were treated urgently and 17 (77%) electively. The embolization was performed with the use of liquid embolic agent, coils, and/or plugs. Adjunctive neck procedures were performed in 55% (n = 12) of the patients. The primary endpoint of this study was freedom from sac enlargement. Key secondary endpoints were technical success and freedom from endoleak-related reinterventions.

RESULTS

Technical success was 100%. The 30-day mortality was 5% (n = 1; acute coronary syndrome). At a mean follow-up of 15.4 months (range 0.1-65.4) the freedom from sac enlargement rate was 76% (16 out of 21). Reintervention-free survival rates at 6, 12, and 24 months were 80%, 68% and 68%, respectively.

CONCLUSIONS

In patients with persistent type Ia endoleak the embolization of the aneurysm sac with or without adjunctive neck procedures can be safely performed, leading to acceptable clinical and radiologic outcomes.

Open repair of a type Ia endoleak with a giant abdominal aortic aneurysm sac

Endovascular aneurysm repair (EVAR) has been widely accepted as a safe and effective treatment for abdominal aortic aneurysm. Endoleaks are the most common complication after EVAR and require urgent interventions. Usually endoleaks can be treated with endovascular procedures using a variety of techniques. Despite these interventions, if the endoleak still persists, conventional open surgery should be evaluated. A 67-year-old man had been treated with EVAR after a ruptured abdominal aortic aneurysm 7 years ago. Later on, a type II endoleak was detected due to the inferior mesenteric artery and treated with coil embolization at the first follow-up year. The patient was admitted to our emergency department due to abdominal pain. Computed tomography angiography demonstrated a type Ia endoleak from the posterior side of the graft with a huge abdominal aortic aneurysm sac (22.9 cm) without rupture. The patient was hemodynamically unstable, and open surgical repair was performed via left anterolateral thoracotomy and laparotomy. Here we report a case where we performed open repair of a type Ia endoleak and discuss the repairing techniques for type Ia endoleak in the light of the literature.

Select type I and type III endoleaks at the completion of fenestrated endovascular aneurysm repair resolve spontaneously

OBJECTIVE

The Society for Vascular Surgery reporting standards for endovascular aneurysm repair (EVAR) consider the presence of a type I or type III endoleak a technical failure. However, the nature and implications of these endoleaks in fenestrated EVAR (FEVAR) are not well understood.

METHODS

We performed a single-center retrospective review of 53 patients who underwent FEVAR with the Zenith Fenestrated AAA Endovascular Graft (Cook Medical, Bloomington, Ind) from 2013 to 2018. We excluded one patient without contrast-enhanced postoperative imaging who was lost to follow-up after discharge. Small, slow, type I and type III endoleaks on completion angiography were routinely observed. We identified patients with completion type I or type III endoleaks by angiography review and characterized endoleak type, location, and rate of resolution on initial postoperative imaging.

RESULTS

Fifty-two patients were included; mean age was 75 ± 8 years, 75% were male, and 91% were white. Of 146 visceral vessels (100 renal arteries and 46 superior mesenteric arteries), 145 (99%) were preserved with 103 fenestrations and 43 scallops; 102 (70%) target vessels were stented. After implantation of all device components, 31 patients (60%) had evidence of type I or type III endoleak. Twelve patients (39%) underwent further intervention at the index procedure, and three endoleaks resolved completely. Twenty-eight patients (54%) had a type I or type III endoleak on completion angiography. There were no differences between patients with and without completion endoleaks in baseline demographics, graft design, neck anatomy, or proportion of cases performed within the instructions for use of the device. Perioperative mortality was 1.9%. On initial postoperative imaging, 27 of 28 (96%) endoleaks resolved spontaneously. One small, persistent type IA or type III endoleak was identified on postoperative day 27 and was observed. This endoleak had resolved completely on computed tomography angiography 6 months postoperatively. In patients without a completion endoleak, one type IA endoleak secondary to graft infolding was discovered on postoperative imaging and was successfully treated with placement of endoanchors and Palmaz stent. Median follow-up was 269 days. No additional type I or type III endoleaks were identified in any patient for the duration of follow-up.

CONCLUSIONS

Whereas completion type I and type III endoleaks are common after FEVAR with the ZFEN device, nearly all of these endoleaks resolve spontaneously by the initial postoperative imaging. These results suggest that select completion endoleaks after FEVAR with the ZFEN device do not require intervention at the index procedure.

Post-EVAR aneurysm sac shrinkage is prognostically favorable, but does not justify withholding follow-up

BACKGROUND

One of the main drawbacks of endovascular aortic aneurysm repair (EVAR) compared to open aortic surgery is the possibility of developing endoleaks and secondary aneurysm rupture, requiring frequent imaging follow-up. This study aims to identify prognostic factors that could be incorporated in follow-up protocols, which might lead to better personalized, lower cost and safe EVAR follow-up.

METHODS

A retrospective study was performed including all patients who underwent elective EVAR from January 2000 to December 2015. Follow-up data were gathered by reviewing medical files for radiographic imaging. Linear and logistic regressions were used to assess predictive factors for aneurysm shrinkage.

RESULTS

In 361 patients, aneurysm sac shrinkage of 10 mm or more was measured in 152 (42.1%) patients. Patients with ≥10-mm aneurysm shrinkage had fewer endoleaks (4.3% vs. 24.6%, P<0.0001) and fewer re-interventions for endoleak (3.0% vs. 10.1%, P=0.007). Aneurysm sac shrinkage was correlated with the absence of endoleak development (OR 0.36, 95% CI 0.19-0.66, P=0.001). In patients who had achieved ≥10-mm shrinkage of the aneurysm sac, no further significant growth was seen, compared to 38 (15.3%) patients who did not attain size reduction (P<0.001).

CONCLUSIONS

Once patients achieve ≥10-mm aneurysm sac shrinkage, they are less prone to developing subsequent aneurysm growth and have significantly lower risk of requiring surgery for endoleaks. However, a small number of patients remain at risk of requiring endoleak surgery after aneurysm shrinkage. Therefore, we would not recommend ceasing life-long imaging follow-up after significant aneurysm sac shrinkage, though it might be safe to increase the interval of follow-up.

Conservative management of type 1A endoleaks at completion angiogram in endovascular repair of infra-renal abdominal aortic aneurysms with current generation stent grafts

Purpose

Proximal type 1A endoleaks on completion intra-operative angiography are not infrequently seen following endovascular abdominal aneurysm repair (EVAR). The natural course of these leaks is not well established. We sought to determine the rate of spontaneous resolution and a conservative treatment approach to these endoleaks.

Methods

All cases involving endovascular repairs of infra-renal abdominal aortic aneurysms resulting in proximal type 1A endoleak on final intra-operative completion angiography were retrospectively reviewed from 1 April 2010 and 30 March 2015. Demographic, pre and post-procedural imaging, and clinical outcomes were reviewed. Summarizing descriptive statistics are reported.

Results

Of the 337 patients who underwent an EVAR, 24 patients (7.1%) had a proximal type 1A endoleak on final intra-operative angiography. Twenty-two of 24 patients (92%) with proximal type 1A endoleaks had spontaneous resolution on follow-up imaging without any intervention, while two (8%) patients had a persistent endoleak. One of these patients required intervention. The median follow-up for patients with resolved endoleaks was 2.5 years vs. 4 and 6 years, respectively, for patients that did not resolve spontaneously.

Conclusion

A conservative approach may be used in the management of patients with proximal type 1A endoleaks on completion angiography once maximum proximal seal was achieved intra-operatively as the vast majority of these leaks spontaneously seal.

A Long-Time Follow-Up Study of a Single-Center Endovascular Aneurysm Repair (Evar) Endoleak Outcomes

Purpose:

The aim of this study was to evaluate the incidence, risk factors, and outcome of endoleaks related to endovascular aneurysm repair (EVAR) procedure at a single center with up to 10 years’ surveillance.

Materials and Methods:

All patients treated with EVAR for an abdominal aorta or iliac aneurysm in a 10-year period at a single cardiovascular center in Denmark were included. Data were collected from a national database and patient journals. Follow-up computed tomography angiography and plain abdominal X-ray reports were reviewed.

Results:

A total of 421 patients were included. There were 125 endoleaks observed in 117 (27.8%) patients after a median 95 days (interquartile range: 90-106 days). There were 16 type I, 107 type II, 1 type III, and 1 type V endoleaks. A total of 33 (7.8%) patients had at least 1 reintervention. Patients with type II endoleaks had significantly fewer active smokers and lower plasma creatinine at baseline. They also more often had one, or both, internal iliac arteries embolized as well as an identified endoleak at the procedural completion angiogram. Non-type II endoleaks were associated with internal iliac artery embolization. There was no association between the occurrence of endoleaks and increased mortality.

Conclusion:

Type II endoleaks are common after EVAR, yet few lead to reintervention. Absence of smoking, low plasma creatinine, embolized iliac arteries, and endoleak on completion angiogram were associated with type II endoleaks, whereas only embolized iliac arteries were associated with non-type II endoleaks. Overall, endoleaks are not associated with increased mortality.

Endovascular Treatment of Various Aortic Pathologies: Review of the Latest Data and Technologies

The technologies and innovations applicable to endovascular treatment for complex aortic pathologies have progressed rapidly over the last two decades. Although the initial outcomes of an endovascular aortic repair have been excellent, as long-term data became available, complications including endoleaks, endograft migration, and endograft infection have become apparent and are of concern. Previously, the indication for endovascular therapy was restricted to descending thoracic aortic aneurysms and abdominal aortic aneurysms. However, its indication has expanded along with the improvement of techniques and devices, and currently, it has become possible to treat pararenal aortic aneurysms and Crawford type 4 thoracoabdominal aortic aneurysm (TAAA) using the off-the-shelf devices. Additionally, custom-made devices allow for the treatment of arch or more extensive TAAAs. Endovascular treatment is applied not only to aneurysms but also to acute/chronic dissections. However, long-term outcomes are still unclear. This article provides an overview of available devices and the results of endovascular treatment for various aortic pathologies.

The Influence of 4 or more Patent Lumbar Arteries on Persistent Type II Endoleak and Sac Expansion after Endovascular Aneurysm Repair

BACKGROUND

This study aimed to review our clinical results and determine how preoperative patent lumbar arteries (LAs) influence the occurrence of type II endoleaks or aneurysm sac enlargement after endovascular aneurysm repair (EVAR) and to identify the preoperative computed tomography findings of persistent type II endoleaks from patent LAs that indicate the need for preventive procedures during EVAR.

METHODS

A total of 293 patients who underwent EVAR for infrarenal abdominal aortic aneurysm (AAA) between August 2007 and July 2013 were reviewed. Follow-up data were available for 194 patients (76% male, mean age 78 ± 6.8 years), and the mean follow-up time was 57 ± 23 months.

RESULTS

The number of patent LAs was identified as a significant positive predictor of persistent type II endoleaks (hazard ratio [HR], 1.4; 95% confidence interval [CI]: 1.2-1.7; P < 0.001) and sac enlargement (≥5 mm) at the 2-year follow-up period (HR, 1.3; 95% CI: 1.1-1.8; P = 0.009) after EVAR, using Cox regression analysis. The receiver operating characteristics curve (AUC: 0.72) showed that a cutoff of 4 patent LAs resulted in a sensitivity of 87% and specificity of 48%. The rates of freedom from sac enlargement (≥5 mm) at 3 and 5 years after EVAR were significantly lower in patients with 4 or more patent LAs than in those with fewer (90% and 76% vs. 96% and 89%; P = 0.0008).

CONCLUSIONS

The number of patent LAs is associated as a significant risk factor with the development of persistent type II endoleaks and sac enlargement after EVAR. Four or more patent LAs should be recognized as the group having an elevated risk of developing late sac enlargement after EVAR.

An Institution-Wide Algorithm for Treatment of Type II Endoleak Following Endovascular Aneurysm Repair (EVAR)

Objectives:

Multiple endovascular techniques have been described for the treatment of persistent type II endoleaks (pT2ELs) causing aneurysm sac growth following endovascular aneurysm repair (EVAR). In the event of a failed endovascular procedure and a pT2EL, a consensus regarding further treatment is lacking, and the literature suggests repeated endovascular attempts are rarely successful. Herein, we propose an algorithm for definitive management of pT2ELs with persistent sac growth following EVAR.

Methods:

A retrospective review of 29 patients who underwent treatment of persistent sac growth in the setting of pT2ELs was performed. Intervention methods were determined at the discretion of the operating surgeon. Aneurysmal sac enlargement was defined as a diameter increase > 5 mm, and persistent endoleak was defined as lasting greater than 6 months.

Results:

From 2000 to 2015, 917 EVAR procedures were performed at our institution. Isolated pT2ELs with sac enlargement were identified in 29 patients. Twenty-five patients underwent direct translumbar sac puncture and coiling and/or Onyx (Onyx, Plymouth, Minnesota) embolization of the culprit vessels. Thirteen (52%) of 25 patients had pT2EL after first endovascular intervention, and 10 (40%) of 25 patients failed 2 endovascular treatments. Of those 10, 7 displayed persistent aneurysmal sac growth and underwent a third embolization procedure. Type II endoleaks persisted in 6 patients; 3 patients were subsequently treated with laparotomy, ligation of lumbar vessels, sac exploration, and sac plication around the endograft. Technical success for this technique was 100%. During a mean follow-up of 38.4 months, no recurrent T2ELs, stent graft migration, and/or disjunction were observed.

Conclusions:

We propose a new algorithm for the management of pT2ELs. If 2 endovascular procedures fail to control of the endoleak, repeat endovascular attempts are not recommended. Endovascular failure should be followed by laparotomy with surgical ligation of culprit feeding vessels followed by sac exploration and plication of the sac, and endoaneurysmorrhaphy.

Carotid Access for Endovascular Repair of Aortic Pathology: A Systematic Review

BACKGROUND

Endovascular repair is now preferred to open access for the management of aortic diseases. This is typically performed via the femoral artery; however, not all patients are eligible for this. This systematic review summarizes the current evidence for utilizing the carotid artery as an alternative access route.

METHODS

A systematic review was conducted as per the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines using 4 electronic databases.

RESULTS

The search found 11 case reports representing 12 patients eligible for analysis (mean age 64.5 years). This included 3 thoracic aneurysms, 3 abdominal aneurysms, 4 penetrating ulcers, 1 endoleak, and 1 pseudoaneurysm. An open procedure was contraindicated in 83% (10/12) due to the poor physiological fitness of the patient. In 75% (9/12) of cases, traditional endovascular access was contraindicated by severe iliac disease. The remainder were contraindicated because of an existing ligated aortic stump (1/12, 8.3%) or technical difficulty with graft deployment via the femoral artery (2/12, 16.7%). There was 1 death, with the 30-day mortality 8.3%. The same patient suffered the only spinal ischemia before death (8.3%). There were no cases of stroke (0%), with one case of transient ischemic attack (8.3%).

CONCLUSIONS

Although there is a relative paucity of literature, this study demonstrates when traditional endovascular access is impossible and an open procedure contraindicated, carotid artery access for endovascular repair of aortic pathology is a viable alternative with good 30-day survival and low rates of neurological sequelae.

Endovascular and open surgical treatment of complications after endovascular aortic aneurysm repair: A single-center experience

While endovascular aortic aneurysm repair (EVAR) has proven to be a safer alternative to open surgical repair for infrarenal abdominal aortic aneurysms (AAA) repair, the development of stent-graft complications mandates follow-up computed tomography imaging to minimize AAA-related mortality. In this single-institution report, adverse EVAR events identified in 150 consecutive patients are detailed. Early morbidity was low (<3%), with only 1 patient death on post-procedure day 2. After discharge (mean follow-up of 24 months), 2 patients died from cancer and one AAA-related mortality occurred after open conversion for stent-graft migration. Although computed tomography imaging detected no EVAR endoleak at 30 days, 19 patients developed an endoleak, including three Type I and four Type III leaks. Our institutional series review confirmed that EVAR of infrarenal AAA is a safe and valid alternative to open surgical repair, but sac embolization at the primary procedure in patients judged to be at high risk for Type II endoleak should be considered.

Risk factors of secondary intervention for type II endoleaks in endovascular aneurysm repair: An 8-year single institution study

BACKGROUND/OBJECTIVES

The natural history of type II endoleaks (T2ELs) is still not completely understood; however, it is widely accepted that those associated with aneurysmal sac growth are harmful. We aimed to review our experience with T2ELs in endovascular aneurysm repair (EVAR).

METHODS

We retrospectively reviewed electronic medical records of all patients who underwent EVAR for infrarenal-type abdominal aortic aneurysms (AAAs) at a single institution from August 2007 to November 2015. Demographic and clinical data were collected. Preoperative contrast computed tomography scans were reviewed to determine aneurysm morphology (the maximum AAA diameter, number of lumbar arteries that enter the AAA sac, size of the inferior mesenteric artery (IMA), proximal neck diameter, proximal neck angle, existence of thrombosis, presence of atheroma, and existence of rupture).

RESULTS

Sixty-two patients underwent EVAR; the follow-up duration was 35.82 ± 31.89 months. There were statistically significant differences in female sex (P = .040), number of lumbar arteries on preoperative computed tomography scans (P = .010), and non-smoking status (P = .031) between patients with and without T2ELs. There were statistically significant differences in the maximum AAA diameter (P = .034) and size of the IMA (P = .043) between patients with and without secondary intervention in T2EL. There was one mortality after EVAR but no mortality associated with T2ELs.

CONCLUSIONS

A more judicious approach that considers risk factors of T2ELs is needed before EVAR. The risk of secondary intervention in patients developing a T2EL after EVAR could increase with the maximum AAA diameter ≥7 cm or IMA ≥3 mm.

Abdominal Aortic Emergencies

This article discusses abdominal aortic emergencies. There is a common thread of risk factors and causes of these diseases, including age, male gender, hypertension, dyslipidemia, and connective tissue disorders. The most common presenting symptom of these disorders is pain, usually in the chest, flank, abdomen, or back. Computed tomography scan is the gold standard for diagnosis of pathologic conditions of the aorta in the hemodynamically stable patient. Treatment consists of a combination of blood pressure and heart rate control and, in many cases, emergent surgical intervention.

Late Sac Rupture due to a Type IV Endoleak after Previous Endovascular Aortic Aneurysm Repair: A Case Report

Type IV endoleaks have been identified as endoleaks of low flow, and rupture risk has been estimated to be minimal in literature. Therefore, conservative treatment has been recommended in most cases. We are presenting a rare case of late rupture due to type IV endoleak that was treated with open repair applying a novel surgical technique.

Treatment of Abdominal Aortic Pathology

Abdominal aortic pathology is a diverse topic, ranging through a broad span of possible pathologies. The treatment options are equally vast, particularly with the ever-expanding endovascular techniques. In this article, we discuss management strategies for abdominal aortic aneurysms and aortic occlusive disease, because they represent some of the most common pathologies encountered in clinical scenarios.

EVAR and OPEN treatment of abdominal aortic aneurysm: What is the role of MMP-9 in the follow-up?

INTRODUCTION

The aim of our study is to verify the role of metalloproteinases in endovascular repair (EVAR) and OPEN surgery treatment for abdominal aortic aneurysm (AAA). Postoperatively, these enzymes could represent an important biomarker to adapt diagnostic tests and further investigations during follow-up.

MATERIAL AND METHOD

From 2004 to 2008, 55 patients were considered with AAA. Of these, 33 patients (mean age: 70.1 years), (mean AAA diameter: 5.4cm) were treated with OPEN surgery (group A) and 22 (mean age: 74.1 years) (mean AAA diameter: 5.1cm) were treated with EVAR. In 17 of them, there were no signs of endoleak (group B1), while in 5 patients, a presence of endoleak (group B2) was detected. Plasma samples were collected in order to determine MMP-9 activity. Enzyme immunoassay was performed preoperatively at 1, 3, 6 and 12 months. Patients treated conventionally were clinically examined after 1 and 12 months by ultrasound. Patients undergoing EVAR treatment were clinically examined by CT scan after 1, 3, 6 and 12 months. The analysis was done by assessing the interaction over time of the MMP-9 value in B1 and B2 groups.

RESULTS

The average values observed for MMP-9 were preoperatively and at 1, 3, 6 and 12 months, respectively: in group A 150.8ng/mL (SD=30.5), 252.5ng/mL (SD=25.2), 315.4ng/mL (SD=22.7), 295.3ng/mL (SD=26.8), 210.7ng/mL (SD=30.2); in group B1 105ng/mL (SD=10.8), 125.6ng/mL (SD=18), 85.8ng/mL (SD=19.9), 95ng/mL (SD=20.2), 80.4ng/mL (SD=15.6); in group B2 149ng/mL (29.2), 375.4ng/mL (SD=40.2), 215ng/mL (SD=35.9), 180ng/mL (SD=20.2), 175ng/mL (SD=33.4). The MMP-9 level was higher in group B2 compared to group B1 (P=0.01), suggesting a correlation with the presence of the endoleak.

CONCLUSIONS

This preliminary study shows that MMP-9 may be a biomarker of the presence of endoleak. Other further investigations and larger series are needed to show that metalloproteases could play a role in the follow-up of EVAR treated patients.