Primary Endovascular Aneurysm Repair Research Articles

Transarterial Coil Embolization for Type II Endoleak After Endovascular Aneurysm Repair (EVAR).

Background Endovascular aneurysm repair (EVAR) has evolved into treatment of choice for infrarenal abdominal aortic aneurysms (AAA). Type II endoleaks, although frequently benign, can lead to sac enlargement and rupture. Management of these endoleaks by endovascular means can be quite challenging and may require complex techniques and assistance of interventional radiologists, not always available in all vascular units. This is a single-center study of management of type II endoleaks with transarterial coil embolization performed by vascular surgeons and with minimum requirements regarding the necessary equipment. Methods From 2017 to 2022, 13 patients with type II endoleak were treated. Local anaesthesia and transfemoral or transbrachial approach was used. The superficial mesenteric artery (SMA) was catheterized and through the Riolan arch, coiling of the inferior mesenteric artery and/or the sac aneurysm was performed. Results The mean time period between the primary EVAR procedure and the transarterial intervention for the endoleak was 3.9 years. Primary technical success was achieved in 11 (84.6%) patients, whilesecondary technical success was 12 (92.3%). In the mean follow-up period, which was 2.6 years, the endoleak was treated successfully in 11 (84.6%) patients. Conclusions Transarterial coil embolization of type II endoleaks is a minimal low-cost procedure, with small percentage of complications, high technical and treatment success rates. It could be considered as a first-line treatment of unresolvable type II endoleaks, minimizing the need for open repair.

Impact of osteoporosis on overall survival following endovascular repair for abdominal aortic aneurysms

ObjectiveTo evaluate the impact of osteoporosis on overall survival following endovascular aneurysm repair (EVAR) for abdominal aortic aneurysms (AAAs). MethodsThis was a retrospective, single-center cohort study on 172 patients who had undergone primary EVAR for AAA between 2016 and 2018. Bone mineral density (BMD) was assessed by measuring the Hounsfield units (HUs) of the 11th thoracic vertebra on preoperative computed tomography; a BMD value of <110 HU was considered osteoporosis. All patients were divided into those with osteoporosis and those without osteoporosis, and long-term outcomes were compared. In addition, hazard ratios of each variable for all-cause mortality were evaluated using univariate and multivariate analysis. ResultsAll 172 patients were divided into two groups: 72 patients (41.9%) with osteoporosis and 100 patients (58.1%) without osteoporosis. The mean age was older and the mean BMD was lower in patients with osteoporosis than patients without osteoporosis (mean, 79.2 ± 7.2 years vs 75.0 ± 8.7 years, respectively; P < .05; 78.1 ± 26.7 HU vs 155.1 ± 36.3 HU, respectively; P < .05). During the median follow-up period of 68 months, overall survival was significantly lower in patients with osteoporosis than patients without osteoporosis (osteoporosis: 63.9% and 36.7% at 5 years and 7 years; nonosteoporosis: 83.8% and 74.6% at 5 years and 7 years, respectively; log-rank P < .05); freedom from aneurysm-related mortality did not differ significantly between groups (osteoporosis: 94.3% and 89.0% at 5 years and 7 years; nonosteoporosis: 100.0% and 96.7% at 5 years and 7 years, respectively; log-rank P = .078). In a multivariate analysis for overall survival after EVAR, coexistence of osteoporosis was found to be an independent risk factor for all-cause mortality (hazard ratio, 1.76; 95% confidence interval, 1.01-3.06; P < .05), as well as variables including age, statin use, sarcopenia, and aneurysm diameter. ConclusionsPatients with osteoporosis showed a higher all-cause mortality after EVAR than patients without osteoporosis. We believe that comorbidity of osteoporosis may be useful in estimating the life expectancy of patients with AAA.

The Role of Narrow Aortic Bifurcation in Affecting EVAR Treatment and Outcomes

The narrow aortic bifurcation (NAB) is considered a risk factor for endograft thrombosis after aorto-biiliac endovascular aneurysm repair (EVAR) for aortic or iliac aneurysm. Nowadays, no consensus on the threshold diameter for the definition of NAB is reached and other aortic bifurcation features are rarely considered. The aim of the study is to assess the EVAR outcomes using bifurcated endograft according to anatomical characteristics of aortic bifurcation. The study included patients treated with primary EVAR from 2016 to 2022. A retrospective analysis of single-center prospectively collected database was performed. Patients were classified in standard aortic bifurcation (SAB) (aortic bifurcation diameter >20mm), NAB (≤20mm and >16mm), and extremely NAB (eNAB) (≤16mm). The 3 groups were compared in terms of patient demographics, risk factors, procedure setting (elective or urgent/emergent), and type of deployed endograft. In NAB and eNAB groups, severe calcification (SC) and length of stenotic aortic bifurcation >10mm (long-NAB) were assessed from preoperative imaging. In SAB, NAB, and eNAB groups, following outcomes were evaluated: rate of intraoperative iliac endograft stenting (unilateral or kissing stenting), primary patency (PP), freedom from endograft-related reintervention, and overall survival during follow-up. The total number of deployed aorto-biiliac endografts was 365 (mean age: 76.6±7.4 years; male 89.3%): SAB 298 (81.6%), NAB 57 (15.6%), and eNAB 10 (2.7%) cases. Female gender, chronic obstructive pulmonary disease patients, and active smokers were more frequent in patients with smaller aortic bifurcation diameter (P=0.002, 0.039, and 0.010, respectively). In NAB and eNAB groups, SC was reported in 18/67 cases (26.9%) and long-NAB in 15/67 cases (25.4%). Patients with eNAB have more frequent SC of aortic bifurcation (60% vs. NAB 21.1%, P=0.018) and long-NAB (50% vs. NAB 17.5%, P=0.023). In SAB, NAB, and eNAB, intraoperative iliac endograft stenting was performed in 34/298 (11.4%), 9/57(15.8%), and 5/10 (50%), respectively (P=0.001). Kissing stenting was performed more frequently in groups with smaller aortic bifurcation diameter (P=0.010). Mean follow-up was 30.2±21.5 months. At 1, 3, and 5years, PP was 98.5%, 96.6%, and 95.6%, respectively. eNAB had lower rate of PP compared to NAB group (P=0.030). Long-NAB had lower rate of PP (P=0.035). At 1, 3, and 5years, endograft-related reintervention was 96.8%, 86.7%, and 76.7%, respectively, with no differences between 3 groups (P=0.423). At 1, 3, and 5years, survival was 92.5%, 77.6%, and 58.1%, respectively, with no difference between SAB, NAB, and eNAB (P=0.673). Female gender, chronic obstructive pulmonary disease patients, and active smokers have more frequently smaller aortic bifurcation diameter. eNAB patients have more challenging anatomical characteristics compared with NAB group, requiring higher rate of intraoperative stenting, especially kissing stenting. Mid-term PP seems to be negatively influenced by aortic bifurcation ≤16mm and long-NAB.

Effectiveness and Safety of Endoanchors in Abdominal and Thoracic Endovascular Aneurysm Repair: A Systematic Review and Meta-analysis

Purpose: This systematic review aimed to summarize the effectiveness and safety of endoanchor, a stabilizing device for the proximal endograft designed to prevent endoleak and stent migration in endovascular aneurysm repair (EVAR) and thoracic endovascular aneurysm repair (TEVAR). Materials and methods: A systematic review and meta-analysis was conducted per the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guideline. Literature up to May 31, 2023 was searched and independently screened from 4 databases. Data were pooled for meta-analysis. Primary outcomes included intraoperative and follow-up endoleak, stent migration, and reintervention rates; sac regression; and 30-day all-cause mortality. Results: Sixteen EVAR (n=1145) and 6 TEVAR studies (n=163) using the Heli-Fx EndoAnchor system were included from 2225 retrieved records. For EVAR patients (mean follow-up=11.9 months), the endoleak, graft migration, and reintervention rates were 3.97% (95% confidence interval [CI]=0.36%-1.99%), 0.004% (95% CI=0.00%-0.76%), and 5.43% (95% CI=0.86%-12.54%), respectively. The endoleak rates for primary and revision EVAR were 0.16% (95% CI=0.00%-1.65%) and 3.60% (95% CI=0.14%-9.72%), respectively. Only 4 cases of 30-day mortality (n=4) were reported in the literature. For TEVAR patients, the endoleak, stent migration, and reintervention rates were 7.4% (95% CI=0.03%-0.13%), 0.2% (95% CI=0.00%-0.06%), and 17.1% (95% CI=0.01%-0.45%), respectively. The 30-day mortality was 0.9% (95% CI=0%-0.12%). Conclusions: Endoanchor fixation in EVAR and TEVAR is effective and safe in preventing and treating endoleak and stent migration. The mortality is minimal in EVAR but higher in TEVAR. Clinical Impact Endoleak, graft migration, and reintervention in EVAR and TEVAR with endoanchor use were rare. Mortality in EVAR was low. The adjunctive deployment of endoanchors is an effective and safe means to prevent and treat endoleak and stent migration in EVAR and TEVAR. Yet, long-term efficacy and safety data and randomized controlled trials would be required to definitively recommend endoanchor use in routine clinical practice.

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

ObjectiveTo analyze the effects of total side branch embolization at endovascular aneurysm repair (EVAR) for abdominal aortic aneurysms on the incidences of persistent type 2 endoleak (pT2EL), changes in sac diameter, and reintervention. MethodsBetween 2013 and 2021, all patients who underwent primary EVAR with a few exceptions were included. Side branch embolization was considered during EVAR for inferior mesenteric artery (IMA) or IMA plus lumbar artery (LA) when feasible for contrast agent use. Outcomes measured were pT2EL, sac diameters, reintervention, ruptures, and aneurysm-related mortality. Radiation exposure and safety outcomes were also reported. ResultsAmong 732 patients who underwent EVAR, 616 (84.2%) were included. Of the 616 patients, 223 (36.2%) did not undergo side branch embolization (NO-E), whereas 228 (37.0%) underwent IMA only (IMA-E) and 165 (26.8%) underwent IMA+LA including median sacral artery (IMA+LA-E). The technical success rate of IMA and LA embolization was 97.0% and 74.7%, respectively. Crude incidences of pT2EL were significantly different from 6 months through 3 years (NO-E, 27.8%; IMA-E, 31.7%; IMA+LA-E, 9.4% at 3 years; P = .007). In the multivariate analysis adjusted for background differences, the incidences of pT2EL were significantly higher in the NO-E (odds ratio [OR], 3.21; 95% confidence intervals [CIs], 1.08-9.57; P = .004) and IMA-E (OR, 4.86; 95% CIs, 1.68-14.11; P = .004) compared with the IMA+LA-E group. Similarly, any reintervention until 3 years was significantly frequent in the NO-E (OR, 5.26; 95% CIs, 1.76-15.70; P = .003) and IMA-E group (OR, 4.19; 95% CIs, 1.38-12.67; P = .01). Surgical conversion and secondary rupture were seen only in 1 patient without any aneurysm-related mortality. Percent sac shrinkage from the baseline was significantly promoted in the IMA+LA group (NO-E, 12.1% ± 16.6%; IMA-E, 11.4% ± 16.7%; IMA+LA-E, 18.0% ± 18.8%; P = .047). Fluoroscopy time was significantly longer in the IMA+LA-E group (NO-E, 60.2 ± 47.4 minutes; IMA-E, 59.3 ± 39.5 minutes; IMA+LA-E, 75.5 ± 42.8 minutes; P < .0001), and so do the dose-area product (NO-E, 424.6 ± 333.4 Gy cm2; IMA-E, 477.7 ± 342.4 Gy cm2; IMA+LA-E, 631.8 ± 449.1 Gy cm2; P < .0001). No embolization-related complications or radiation-related adverse events were recorded. ConclusionsPre-emptive embolization of IMA, LAs, and median sacral artery at the time of EVAR reduced the incidences of pT2EL and any reintervention and promoted sac shrinkage during the follow-up period of 3 years.

Abstract 530: Explantation Vs Graft Preserving Strategy Following Primary Endovascular Aneurysm Repair

Background: Continuous sac expansion could result in rupture, requiring aggressive management with re-intervention to abolish the risk of rupture. Re-intervention could be achieved through salvage of the primary endograft through graft preserving strategy or explantation as necessary. We aim to scrutinise our 20 years of EVAR practice, strategies indications for management and re-interventions following primary endovascular aneurysm repair (EVAR). Methods: We performed 1555 aortic interventions over study period, including 910 EVARs. Using conventional and innovative diagnostic modalities with Prone contrASt enHanced computed tomography Angiography (PASHA), 136 endoleaks (ELs) were identified (15 type I, 98 type II; 18 type III; 5 type IV). Results: In total, 4.84% (44/910) patients underwent re-intervention post-primary EVAR; 18 EVAR GORE SalvAge Fabric Technique (ARAFAT), 12 double breastings, and 14 explantations (Figure 1) . Mean EL detection duration following primary EVAR was 53.3 ± 6.82 months, while re-intervention time was 70.2 ± 6.98 months. Mean sac size before the primary EVAR and re-intervention were 6.00 and 7.51 cm. Polyester (61.40%, 12/18) was the most commonly employed stent-graft material. Factors associated with the need for reintervention and likelihood of chronic fabric fatigue failure (CFFF) included the use of more than three modular stent-graft components (3.42 ± 1.31); with the proximal stent-graft diameter of 31.6 ± 3.80 cm and the use of iliac limbs more than 18 mm. We had one peri-operative mortality following explantation due to sepsis-induced multiorgan failure. Conclusions: Increasing complications post-EVAR necessitates developing and studying re-intervention strategies to salvage existing endograft and/or address graft-related complications. Re-intervention could be achieved through salvage of the primary endograft through graft preserving strategy or explantation as necessary.

Risk for surgical interventions following endovascular aneurysm repair with Endologix AFX or AFX2 Endovascular AAA Systems compared with other devices

ObjectiveTo evaluate the risk for 90-day returns to care and long-term subsequent surgical interventions after primary endovascular aneurysm repair (EVAR) with an Endologix AFX Endovascular AAA System compared with three other high-volume endograft devices. MethodsWe conducted a matched cohort study using data from Kaiser Permanente's Endovascular Stent Graft Registry. Patients aged ≥18 years who underwent primary EVAR for AAA in the health care system from January 1, 2011, to December 31, 2017, comprised the eligible study sample. The treatment group included patients who received an Endologix AFX or AFX2 device (n = 470). Patients who received one of three other high-volume endograft devices used within the health care system comprised the eligible comparison group (n = 2122). These patients were 2:1 propensity score matched without replacement to patients who received an Endologix device based on a number of patient and procedural characteristics. After the application of matching, conditional logistic regression was used to evaluate the likelihood for 90-day emergency department visit and readmission. Cause-specific Cox regression was used to evaluate the long-term risk of endoleak, graft revision, secondary reintervention (not including revision), conversion to open repair, and rupture during follow-up. Cox proportional hazards regression was used to evaluate the risk of mortality (overall and aneurysm related). ResultsThe final matched study sample included 470 patients who received an Endologix AFX or AFX2 device and 940 patients who received a different high-volume device. compared with the other devices, AFX/AFX2 had a higher risk for type III endoleak (hazard ratio [HR], 38.79; 95% confidence interval [CI], 14.51-103.67), revision surgery >1 year after the primary EVAR (HR, 4.50; 95% CI, 3.10-6.54), rupture (HR, 6.52; 95% CI, 1.73-24.63), and aneurysm-related mortality (HR, 2.43; 95% CI, 1.32-4.47) was observed with the use of AFX/AFX2. ConclusionsIn our matched cohort study, patients who received an Endologix AFX System during their primary EVAR had a higher risk for several adverse longitudinal outcomes, as well as aneurysm-related mortality, when compared with patients who received other high-volume devices. Patients who have received these devices should be monitored closely after EVAR.

Shortest Apposition Length at the First Postoperative Computed Tomography Angiography Identifies Patients at Risk for Developing a Late Type Ia Endoleak After Endovascular Aneurysm Repair

Purpose: Imaging surveillance following endovascular aneurysm repair (EVAR) is strictly recommended. This study investigates the value of endograft apposition and position relative to the aortic neck on the first postoperative computed tomography angiography (CTA) in determining patients at risk for a late type Ia endoleak (T1aEL). Materials and Methods: Patients with a T1aEL after the first postoperative CTA were selected from a consecutive database and matched with uncomplicated controls. Endograft apposition and position, including the shortest apposition length (SAL), were determined on the first postoperative CTA. The SAL is the shortest distance between the proximal endograft fabric and the first slice where circumferential apposition with the aortic wall is lost. Differences in endograft apposition at the first postoperative CTA were compared between groups. Logistic regression analysis identified independent predictors for late T1aEL. Results: A total of 32 patients with a late T1aEL were included and matched with 32 uncomplicated controls. Median follow-up after primary EVAR was 62.0 (interquartile range [IQR]: 36.8, 83.5) months in the T1aEL group compared with 47.5 (IQR: 34.0, 79.3) months in the control group; p=0.265. Median preoperative neck diameter was significantly larger in the T1aEL group than in the control group (26.6 [IQR: 24.9, 29.6] mm versus 23.4 [IQR: 22.5, 25.3] mm); p<0.001. Patients in the T1aEL group had a median SAL of 11.6 (IQR: 4.3, 20.5) mm compared with 20.7 (IQR: 13.1, 24.9) mm in the control group; p=0.002. SAL <10mm on the first postoperative CTA (odds ratio [OR]: 9.63, 95% confidence interval [CI]: 1.60–57.99) and larger neck diameter (OR: 1.80, 95% CI: 1.26–2.57) were independent predictors for developing a late T1aEL. Conclusion: Preoperative neck diameter and SAL on the first postoperative CTA following EVAR are important predictors for the development of a late T1aEL. Patients with a SAL of <10mm had a significantly higher risk of developing a late T1aEL. Future research should determine whether these patients would benefit from reintervention before an actual T1aEL is present. Clinical Impact Understanding the mechanisms of endovascular aneurysm repair failure is essential to further enhance clinical outcomes. Adequate proximal sealing is necessary to foster freedom from type 1a endoleak. This study demonstrates that the shortest apposition length (SAL) at the first postoperative computed tomography angiography (CTA) is able to identify patients at risk for a late type 1a endoleak. Especially patients with a SAL <10mm are at high risk. Currently, the guidelines advice repeated imaging with CTA in patients with a seal <10mm. Future research should determine whether these patients would benefit from re-intervention before an actual type 1a endoleak is present.

Two decades of experience in explantation and graft preserving strategies following primary endovascular aneurysm repair and lessons learned.

We aim to scrutinize our evolving re-intervention strategies following primary endovascular aortic aneurysm repair (EVAR) - EVAR GORE SalvAge Fabric Technique (ARAFAT), aortic sac double breasting with endograft preservation, and stent-graft explantation. We performed 1,555 aortic interventions over the study period, including 910 EVARs. Factors associated with the need for reintervention and the likelihood of chronic fabric fatigue failure (CFFF) were investigated. Using conventional and innovative diagnostic modalities with Prone contrASt enHanced computed tomography Angiography (PASHA), 136 endoleaks (ELs) were identified (15 type I, 98 type II; 18 type III; 5 type IV). Forty-four (4.84%) patients underwent re-intervention post-primary EVAR; 18 ARAFATs, 12 double breastings, and 14 explantations. Choice of re-intervention was based on patient fitness and mode of failure. Mean EL detection duration following primary EVAR was 53.3 ± 6.82 months, while mean time to re-intervention was 70.20 ± 6.98 months. The mean sac size before the primary EVAR and re-intervention was 6.00 ± 1.75 cm and 7.51 ± 1.94 cm, respectively. Polyester (61.40%) was the most commonly employed stent-graft material. Use of more than three modular stent-graft components (3.42 ± 1.31, p = 0.846); with the proximal stent-graft diameter of 31.6 ± 3.80 cm (p = 0.651) and the use of iliac limbs more than 17 mm (p = 0.364), all added together are contributing factors. We had one peri-operative mortality following explantation due to sepsis-induced multiorgan failure. Our re-intervention strategies matured from stent graft explantation to graft preservation with endovascular relining of the stent-graft. Graft preservation with aortic sacotomy and double breasting were used to manage concealed ELs due to aortic hygroma.

O077 Explantation vs graft preserving strategy following primary endovascular aneurysm repair: two decades of EVAR and lessons learned

Abstract Introduction Continuous sac expansion could result in rupture, requiring aggressive management with reintervention to abolish the risk of rupture. Re-intervention could be achieved through salvage of the primary endograft through graft preserving strategy or explantation as necessary. We aimed to scrutinise our 20 years of EVAR practice, strategies indications for management and reinterventions following primary endovascular aneurysm repair (EVAR). Methods We performed 1480 aortic interventions over the study period, including 910 EVARs. Using conventional and innovative diagnostic modalities with Prone contrASt enHanced computed tomography Angiography (PASHA), 133 endoleaks (ELs) were identified (15 type I, 98 type II; 18 type III; 5 type IV). Results In total, 44 patients underwent re-intervention post-primary EVAR;18 EVAR GORE SalvAge Fabric Technique (ARAFAT), 12 double breastings, and 14 explantations. Mean EL detection duration following primary EVAR was 53.3 ± 6.82 months, while re-intervention time was 70.2 ± 6.98 months. Mean sac size before the primary EVAR and re-intervention were 6.00 and 7.51 cm. Polyester (61.40%) was the most commonly employed stent-graft material. Factors associated with the need for reintervention and the likelihood of chronic fabric fatigue failure (CFFF) included the use of more than three modular stent-graft components (3.42 ± 1.31); with the proximal stent-graft diameter of 31.6 ± 3.80 cm and the use of iliac limbs more than 18 mm. We had one peri-operative mortality following explantation due to sepsis-induced multiorgan failure. Conclusion Increasing complications post-EVAR necessitates developing and studying reintervention strategies to salvage existing endograft and/or address graft-related complications. Take-home message Increasing complications post-EVAR necessitates developing and studying re-intervention strategies to salvage existing endograft and/or address graft-related complications.

O071 An innovative prone contrast enhancement computed tomography angiography (PASHA) protocol to diagnose concealed endoleak and aortic sac hygroma

Abstract Introduction Standard 4-phase supine computed tomography angiography (CTA) scans are unable to detect smaller fabric tear (&amp;lt; 1–2 mm) following EVAR, which are erroneously interpreted as type IV or V endoleak (EL). Here, we propose a novel diagnostic technique, ‘Prone contrASt enhanced computed tomography Angiography’ (PASHA)' that uses time-resolved four-phase CTA protocol to detect and classify concealed ELs. Methods We employed PASHA protocol in 46 patients after continuous sac expansion following primary EVAR where the standard 4-phase CTA could not identify the EL source. PASHA protocol uses a prone position during standard 4-phase CTA, which displaces the aorta anteriorly by approximately 5 mm, shortening the anterior cortex distance and allowing fluid transudation due to gravity with maximal EL enhancements. Results The average numbers of CT scans performed before diagnosing EL with PASHA protocol were 3.4 ±1.5 (range: 1–6). PASHA protocol demonstrated EL in all 46 cases that the standard supine 4-phase CTA could not identify. PASHA protocol effectively enhanced the degree of contrast infiltration into the aortic sac in all the patients. Conclusion PASHA is a multi-phase positional CTA technique that enhances the degree of contrast infiltration into the aortic sac when micro-leaks are present, increasing the EL detection rate following EVAR and strategically mapping successful future intervention. Take-home message Prone contrASt enHanced computed tomography Angiography (PASHA) is a multi-phase positional computed tomography angiography (CTA) technique that enhances the degree of contrast infiltration into the aortic sac when micro-leaks are present. PASHA increases the endoleak (EL) detection rate following endovascular aneurysm repair (EVAR) and strategically maps successful future interventions.

Explantation Versus Graft-Preserving Strategy Following Primary Endovascular Aneurysm Repair: Two Decades of EVAR and Lessons Learned

Continuous sac expansion could result in rupture, requiring aggressive management with reintervention to abolish the risk of rupture. Reintervention can be achieved through salvage of the primary endograft using a graft-preserving strategy or explantation, as necessary. We scrutinized our 20 years of endovascular aneurysm repair (EVAR) practice, strategy indications for management and reinterventions following primary EVAR.

Midterm outcomes of aneurysm repair with the Cook Zenith Alpha abdominal endovascular graft

ObjectiveOutcome reports after endovascular aneurysm repair (EVAR) using the low-profile Zenith Alpha Abdominal Endovascular grafts (Cook Medical, Bjæverskov, Denmark) are sparse. We present results from a single-center cohort treated with the Zenith Alpha, from a period where the graft was the primary EVAR device choice. The aim of the study was to evaluate short- and midterm outcomes of patients treated with the Zenith Alpha. MethodsA retrospective single-center study was performed including all patients treated with the Zenith Alpha graft from October 1, 2015 to September 30, 2018. All patients underwent computed tomography angiography (CTA) imaging preoperatively as well as at 3 and 12 months postoperatively. Hereafter, patients were followed yearly with duplex ultrasound and clinical exams. Additional imaging was performed on indication. All CTAs were analyzed using three-dimensional reconstruction software (Aquarius, TeraRecon, Durham, NC). Data was extracted from electronic charts according to a protocol that remained unchanged until the end of the study (December 31, 2020). The following outcomes were assessed according to Society for Vascular Surgery/International Society of Cardiovascular Surgeons reporting criteria: aortic-related and all-cause mortality, reinterventions, instruction for use (IFU) violations, endoleaks (ELs), and aneurysm shrinkage. ResultsA total of 241 patients were treated with the Zenith Alpha, and 214 (89%) were asymptomatic repairs. Technical success was achieved in 238 patients (99%). One hundred fifty-seven patients (65%) received implantation outside IFU. The median hospital length of stay was 2 days (interquartile range, 2-3 days). The median clinical follow-up was 35.1 months (interquartile range, 28.8-47.5 months). The 4-year Kaplan-Meier estimate of freedom from reintervention was 66% (95% confidence interval, 59%-73%). The main reasons for reinterventions were iliac limb stenosis and occlusion (n = 30; 12%) and type 2 EL (n = 13; 5%). Overall, significantly more patients with grafts implanted outside distal IFU developed type 1B ELs (n = 10/11; P = .009). Aneurysm sac shrinkage was observed in 48 patients (25%) 1 year postoperatively. The Kaplan-Meier estimate of freedom from aortic-related mortality was 99% (95% confidence interval, 98%-100%) 4 years postoperatively. ConclusionsEVAR with the Zenith Alpha shows acceptable freedom from aortic-related mortality up to 4 years postoperatively. The majority of patients were treated outside IFU, and significantly more type 1B ELs appeared in this subgroup of patients. The leading cause for reintervention was impaired limb patency. The root cause for impaired limb patency requires further investigation.

Intra-aneurysm sac pressure measurement using a thin pressure wire during endovascular aneurysm repair.

An endoleak is a typical complication of endovascular aneurysm repair (EVAR). It is characterized by persistent blood flow between a stent graft and the aneurysm sac. Usually, it can be visualized during primary EVAR, but in many cases, this remains impossible. Therefore, other methods of endoleak assessment are urgently needed. The measurement of aneurysm sac pressure (ASP) seems to be a promising direction of research in this area. We aimed to evaluate the safety and efficacy of a new method for invasive pressure measurement inside the abdominal aortic aneurysm (AAA) during EVAR. We also assessed a correlation between pressure values and early angiographic occurrence of an endoleak after the procedure. A total of 20 patients with AAA were included in this experimental prospective study. During EVAR, systolic, diastolic and mean pressure values were recorded both for ASP and aortic pressure (AP) before procedure, after stent graft opening and after final stent graft ballooning. The measurements were successfully obtained in all participants without any complications. There were no significant differences between all ASP and AP before procedure. After the procedure, blood pressure significantly decreased in the aneurysm sac but not in the aorta. Systolic ASP was significantly lower than systolic AP both after stent graft opening (80.4 ±20.9 mm Hg compared to 110.7 ±21.6 mm Hg, p < 0.01) and after its balloon post-dilatation (65.6 ±26.1 mm Hg compared to 107.4 ±22.1 mm Hg, p < 0.001). Diastolic ASP decreased significantly in comparison to diastolic AP only after stent graft ballooning (48.0 ±14.6 mm Hg compared to 56.4 ±13.6 mm Hg, p < 0.05). Our study confirmed that the novel method for the measurement of ASP during EVAR, using a thin pressure wire, is feasible and safe.

Management of Concealed Type IV Endoleak and Aortic Sac Hygroma by Prone ContrASt EnHancement Computed Tomography Angiography

Aortic sac hygroma and concealed endoleaks (EL) after endovascular aneurysm repair (EVAR) of abdominal aortic aneurysm needs particular attention with aggressive management as they are associated with rapid sac expansion and rupture risk. However, they can be erroneously reported as type IV or V EL with supine computed tomography (CT) scans, leading to delay in management. Therefore, we describe a novel diagnostic technique, 'Prone contrASt enHanced computed tomography Angiography' (PASHA), to document concealed EL METHODS: We present eight case descriptions with continuous sac expansion after primary EVAR. Management began with diagnosis using the PASHA imaging technique. PASHA is a multiphase CTA positional technique for increasing the accuracy of detecting EL after EVAR. Furthermore, the PASHA imaging technique also guides whether the open or endovascular intervention could be used effectively to manage the sac expansion. In synchrony with the PASHA technique, "EVAR GORE SalvAge FAbric Technique" (ARAFAT) was to salvage previous EVAR. The PASHA technique diagnosed all cases of type IIIb EL, as it enhanced the degree of contrast infiltration into the aortic sac when microleaks were present. ARAFAT was effectively used in five elderly patients. Another three had an open conversion; two with double breasting of the aortic sac and one EVAR explantation. The PASHA protocol helped classify and localize the concealed EL (type IV, V), which were not appropriately diagnosed by supine CT protocols. PASHA and ARAFAT were used as a fully functioning protocol to overcome apparent challenges in accurate diagnosis and subsequent concealed EL management in high-risk patients.

National Numbers of Secondary Aortic Reinterventions after Primary Abdominal Aortic Aneurysm Surgery from the Dutch Surgical Aneurysm Audit

Long-term secondary aortic reinterventions (SARs) can be a sign of (lack of) effectiveness of abdominal aortic aneurysm (AAA) surgery. This study provides insight into the national number of SARs after primary AAA repair by endovascular aneurysm repair (EVAR) or by open surgical repair in the Netherlands. Observational study included all patients undergoing SAR between 2016 and 2017, registered in the compulsory Dutch Surgical Aneurysm Audit (DSAA). The DSAA started in 2013, SARs are registered from 2016. Characteristics of SAR and postoperative outcomes (mortality/complications) were analyzed, stratified by urgency of SAR. Data of SARs were merged with data of their preceded primary AAA repair, registered in the DSAA after January 2013. In these patients undergoing SAR, treatment characteristics of the preceded primary AAA repair were additionally described, with focus on differences between stent grafts. Between 2016 and 2017, 691 patients underwent SAR, this concerned 9.3% of all AAA procedures (infrarenal/juxtarenal/suprarenal) in the Netherlands (77% elective/11% acute symptomatic/12% ruptured). Endoleak (60%) was the most frequent indication for SAR. SARs were performed with EVAR in 66%. Postoperative mortalities after SAR were 3.4%, 11%, and 29% in elective, acute symptomatic, and ruptured patients, respectively. In 26% (n=181) of the patients undergoing SAR their primary AAA repair was performed after January 2013 and data of primary and SAR procedures could be merged. In 93% (n=136), primary AAA repair was EVAR. Endografts primarily used were nitinol/polyester (62%), nitinol/polytetrafluoroethylene (8%), endovascular sealing (21%), and others (9%), compared with their national market share of 76% (odds ratio [OR], 0.52; 95% confidence interval [CI], 0.38-0.71), 15% (OR, 0.50; CI, 0.29-0.89), 4.9% (OR, 5.04; CI, 3.44-7.38), and 4.1% (OR, 2.81; CI, 1.66-4.74), respectively. In the Netherlands, about one-tenth of the annual AAA procedures concerns an SAR. A quarter of this cohort had an SAR within 1-5years after their primary AAA repair. Most SARs followed after primary EVAR procedures, in which an overrepresentation of endovascular sealing grafts was seen. Postoperative mortality after SAR is comparable with primary AAA repair.

Correlation of Baseline Plasma and Inguinal Connective Tissue Metalloproteinases and Their Inhibitors With Late High-Pressure Endoleak After Endovascular Aneurysm Repair: Long-term Results

Purpose: To investigate whether plasma and connective tissue matrix metalloproteinases (MMP) and their inhibitors (TIMP) may predict late high-pressure endoleak after endovascular aneurysm repair (EVAR). Materials and Methods: Samples of inguinal fascia and blood were collected in 72 consecutive patients (mean age 73.1 years; 68 men) undergoing primary EVAR with the Endurant stent-graft. Baseline plasma levels of MMP-2, MMP-9, TIMP-1, and TIMP-2 and baseline MMP-2 and MMP-9 activity estimated using gelatin zymography (GZ) were compared between patients who developed late endoleak in follow-up and those who did not. Subgroup analyses were performed between patients with (n=18) and without inguinal hernias and between patients with moderate-diameter (50–59 mm; n=45) or large-diameter (≥60 mm; n=27) abdominal aortic aneurysms (AAA) at primary EVAR. Results: The mean follow-up period was 63.1 months (range 7.5–91.5), during which time 13 (18.1%) patients developed type I (6 Ia and 5 Ib) or 2 type III endoleaks. Only GZ-analyzed proMMP-9 concentrations were higher in the endoleak group than in patients without endoleak (mean difference 8.44, 95% CI −19.653 to −1.087, p=0.03). The patients with primary inguinal hernia at presentation had significantly higher tissue TIMP-2 values (0.8±0.7 vs 0.5±0.4, p=0.018) but lower plasma total (pro- + active) MMP-9 values (11.9±7.8 vs 16.2±7.4, p=0.042) than patients without hernias at the time of EVAR. Patients with AAAs ≥60 mm had significantly higher mean tissue homogenate levels of total (pro- + active) MMP-9 (p=0.025) and total (pro- + active) MMP-2 (p=0.049) as well as higher proMMP-9 (p=0.018) and total (pro- + active) MMP-9 (p=0.021) levels based on GZ compared to patients with moderate-diameter AAAs. Regression analysis revealed a significant association between total (pro- + active) MMP-9 plasma samples and the presence of hernia (OR 0.899, 95% CI 0.817 to 0.989, p=0.029) and between GZ-analyzed proMMP-9 and late endoleak (OR 1.055, 95% CI 1.007 to 1.106, p=0.025). GZ-analyzed proMMP-9 and active MMP-9 were strong predictors of late endoleak in patients with hernia (p=0.012 and p=0.044, respectively) and in patients with AAAs ≥60 mm (p=0.018 and p=0.041 respectively). Conclusion: Inguinal fascial tissue proMMP-9 significantly predicted late endoleak. ProMMP-9 and active MMP-9 biomarkers are significantly associated with late endoleak in hernia patients and in patients with AAAs ≥60 mm. Considering the clinical association between hernia and AAA and the fact that the AAA wall connective tissue environment remains exposed to systemic circulation after EVAR, inguinal fascia extracellular matrix dysregulation and altered MMP activity may reflect similar changes in AAA biology, leading to complications such as endoleak.

Late surgical conversions after abdominal endovascular aortic repair: underlying mechanisms, clinical results and strategies for prevention.

Our goal was to report our results of late surgical conversion after endovascular aneurysm repair (EVAR). Variables analysed included baseline data, preinterventional anatomy, type of endovascular intervention, indications for conversion, operative technique, postoperative complications and follow-up survival rate. Between April 2011 and May 2018, 16 patients with late complications after EVAR underwent open surgical conversion at our institution. The mean age was 73.6 [standard deviation (SD) 8.9] years. There were 3 (18.8%) female patients. In 15 patients, the indication for primary EVAR was abdominal aortic aneurysm, and in 1 patient, chronic abdominal aortic dissection. Five patients underwent secondary EVAR service interventions for endoleak treatment between the index EVAR and the final secondary surgical conversion. Thirteen patients underwent surgery in an elective setting and 3 patients underwent emergency surgery. The mean time from EVAR to open surgical conversion was 6.31 (SD 4.0) years (range 1.2-16.0 years). The most common indication for conversion was endoleak formation (n = 12, 75%), followed by 3 cases of aortic rupture (1 patient with primary type 1 endoleak) and 2 cases of stent graft infection-1 with and 1 without an aortoduodenal fistula. One patient died during emergency open surgery of cardiopulmonary instability. Three patients developed postoperative renal dysfunction with recovery of their renal function before discharge. The in-hospital mortality rate was 12.5%. The median follow-up was 16.5 months (interquartile range 21 months). Freedom from death and aortic reintervention was 100%, respectively. After careful review of the index computed tomography scans for EVAR, the majority of failures could have been anticipated due to trade-offs with regard to length, diameter, morphology, shape and angulation of the proximal and/or distal landing zone. Despite being a challenging operation, late surgical conversion after EVAR yields excellent results with regard to outcome and freedom from the need for further aortic interventions. An anticipative strategy adhering to current recommendations for using or refraining from using EVAR in patients with anatomical challenges will help reduce the need for secondary surgical conversions and keep them to minimum.

Changes in Apposition of Endograft Limbs in the Iliac Arteries After Endovascular Aneurysm Repair: Determination With New Computed Tomography–Applied Software

Purpose: To validate new computed tomography (CT)–applied software used to determine endograft limb position and apposition after endovascular aneurysm repair (EVAR). Materials and Methods: Twelve EVAR patients (mean age 81±6 years; 10 men) with distal stent-graft extensions for 15 (3 bilateral) type Ib endoleaks during follow-up were selected based on the availability of the following CT studies: pre-EVAR, 1 month, and the penultimate scan prior to the scan disclosing the type Ib endoleak. Twelve patients (mean age 82±7 years; 11 men) without endoleak and a similar interval between the primary EVAR procedure and the penultimate CT scan of the endoleak group were selected as controls using measurements from both endograft limbs (n=21, 3 excluded). Prototype Vascular Imaging Analysis software was adapted to calculate 6 parameters for the distal apposition zone: fabric distance, shortest apposition length, endograft diameter, iliac seal surface (ISS), iliac endograft apposition surface (IEAS), and percentage of iliac surface coverage (IEAS/ISS × 100). Measurements were performed on the preoperative, first postoperative, and penultimate/matched follow-up CT scans. Interobserver variability was assessed with the intraclass correlation coefficient (ICC). Continuous data are presented as the median [interquartile range (IQR) Q1, Q3]. Results: CTA follow-up was not significantly different between the endoleak and control groups [30 months (IQR 18, 58) vs 36 months (IQR 21, 59), p=0.843]. Interobserver agreement was good to excellent for all parameters (ICC 0.879–0.985). Preoperative anatomy and endograft dimensions on the first follow-up CTA scan did not differ significantly between the groups. When the penultimate CTA scan was compared with the first postoperative CT scan, endograft dimensions had significantly changed in the endoleak group; importantly, apposition was significantly decreased, and fabric distance was significantly increased, indicating limb retraction. Differences in changes in endograft dimensions were significant between the groups. Conclusion: New CT-applied software was introduced to visualize apposition and position changes of endograft limbs during follow-up. The software demonstrated good-to-excellent interobserver agreement and enabled accurate analysis of post-EVAR endograft dimensions. Significant changes in apposition and position were observed with the software on the penultimate CT scan prior to diagnosis of type Ib endoleak.

Management of failed endovascular aortic aneurysm repair with explantation or fenestrated-branched endovascular aortic aneurysm repair

ObjectiveThe incidence of failed endovascular aneurysm repair (EVAR) is increasing, and understanding the different methods of management and repair is paramount. The objective of this study was to evaluate the clinical management and rescue of failed EVAR by either explantation or fenestrated-branched EVAR (F/B-EVAR). MethodsA retrospective analysis (1999-2016) of 247 patients who underwent either explantation (n = 162) or F/B-EVAR (n = 85) for failed EVAR was performed. F/B-EVAR was performed under a physician-sponsored investigational device exemption. Demographics of the patients, clinical presentation and failure etiology, perioperative management, rate of reinterventions, morbidity, and mortality were analyzed. Those undergoing surgical explantation were compared with those undergoing F/B-EVAR conversion. Statistical analysis included multivariable logistic regressions, Fisher exact test, and χ2 test. ResultsThe majority of patients were male (n = 216 [87%]), with a mean age of 75 years (range, 50-93 years). The mean time from primary EVAR was higher in F/B-EVAR (46 ± 7 months vs 69 ± 41 months; P < .001). Graft manufacturer did not differ between those requiring explantation and those having endovascular rescue (P = .170). All emergencies (n = 24 [10%]) and infections (n = 28 [11%]) were treated with open conversion. Endoleak was the most common reason for failure in both explantation and F/B-EVAR groups (75% vs 64%, respectively; P = .052). Type I endoleak was the most common endoleak reported in both groups, occurring more frequently in F/B-EVAR (64% vs 40%; P < .001); type II endoleak was more common in those undergoing open repair (28% vs 2%; P < .001). Graft migration (12% vs 26%; P = .005) and neck degeneration/disease progression (14% vs 59%; P < .001) were more prevalent in F/B-EVAR, but aneurysm enlargement was more common in explantation (68% vs 33%; P < .001). Thirty-day reintervention rates did not differ between F/B-EVAR and explantation (odds ratio, 0.6258; 95% confidence interval, 0.2-1.86; P = .4115); however, 30-day mortality was lower in the F/B-EVAR group (5% vs 10%; P = .0192). Similarly, aneurysm-related mortality was also lower in the F/B-EVAR group (hazard ratio, 0.0683; 95% confidence interval, 0.01-0.44; P = .0048). A subset analysis excluding emergencies and infections did not alter the lack of difference in terms of freedom from reinterventions (P = .1175), 30-day mortality (P = .6329), or aneurysm-related mortality (P = .7849). ConclusionsExplantation and F/B-EVAR are necessary options in treating patients with failed EVAR, and both techniques have competitive results. Different modes of failure may point to a preferred method of treatment; consequently, rescue of failed EVAR should be individualized according to each patient’s presentation and resources available.