The AAA With a Challenging Neck: Outcome of Open Versus Endovascular Repair With Standard and Fenestrated Stent-Grafts

Outcomes of advanced EVAR versus open surgery in the management of complex abdominal aortic aneurysm repair: A systematic review and meta-analysis

BACKGROUND

Open surgery is still acknowledged as the gold standard for complex abdominal aortic aneurysm (c-AAA). Recently, advanced-endovascular aortic aneurysm repair (EVAR) for c-AAA has been developed, but its effectiveness compared to open surgery is still unclear.

METHOD

A systematic search was performed on the MEDLINE through PubMed and ScienceDirect databases. The search was aimed to investigate outcomes of both fenestrated- and chimney-EVAR (consider as advanced EVAR) compared to open surgery in c-AAA. Outcomes included postoperative complications, 30-day mortality, long-term mortality, and reintervention rate. Data were collected using the Mantel-Haenszel fixed effects model with relative risk (RR) as the effect size with 95% confidence interval (CI).

RESULTS

A total of 25 studies (n = 12,845 patients) were included in our study. The results demonstrated that advanced-EVAR correlated with diminished postoperative complications (RR 0.53; 95% CI 0.49-0.57; p < 0.001) compared to open surgery. Advanced-EVAR was associated with lower 30-day mortality compared to open surgery (RR 0.66; 95% CI 0.53-0.82; p < 0.001). Subgroup analysis revealed that fenestrated-EVAR resulted in superior outcomes (p < 0.001), whereas the chimney-EVAR subgroup did not show significant differences (p = 0.79), compared to open surgery in terms of 30-day mortality. Unfortunately, advanced-EVAR was associated with a higher long-term mortality rate (RR 1.46; 95% CI 1.20-1.78; p < 0.001) and a higher reintervention rate (RR 1.26; 95% CI 1.01-1.59; p = 0.04) compared to open surgery.

CONCLUSION

Advanced EVAR, especially fenestrated-EVAR, presented better short-term outcomes compared to open surgery; however, it failed to demonstrate superiority over open surgery in improving long-term outcomes.

Abdominal Stent Grafting With Coil Embolization for an Abdominal Aortic Aneurysm Sac With a Short Neck

A 68-year-old man underwent endovascular abdominal aortic aneurysm repair for a two-humped abdominal aortic aneurysm (AAA) with a short neck. The abdominal aorta had severe calcification, suggesting a high risk for type Ia endoleak. Initially, a catheter was placed in the aneurysm sac, followed by stent graft deployment. Then, coils were inserted into the aneurysm neck. Subsequently, the type Ia endoleak was resolved. One year after the surgery, no evidence of endoleak was observed, and the aneurysm size had decreased by 10 mm. Therefore, this procedure may be effective for short-neck AAAs.

Novel conformable stent-graft repair of abdominal aortic aneurysms with hostile neck anatomy: A single-centre experience

OBJECTIVES

Abdominal aortic aneurysms (AAAs) demonstrating hostile neck anatomy (HNA) are associated with increased perioperative risk and mortality. A number of these patients are not suitable for standard endovascular aneurysm repair (EVAR) and are high risk for open surgery. We present our experience with the first implantations in Scotland of a novel conformable aortic stent-graft designed to overcome some of the challenges of HNAs.

METHODS

From May 2018 to March 2022, 24 consecutive patients with non-ruptured AAAs demonstrating HNAs (neck length < 15 mm, or angulation > 60°) were treated with GORE Excluder Conformable AAA endoprosthesis (CLEVAR) (CEXC Device, W.L. Gore and Associates, Flagstaff, AZ, USA) at a Scottish vascular centre. We assessed clinical outcomes and technical success of CLEVAR during deployment, primary admission and the post-operative period at 3- and 12-month clinical follow-up alongside CT angiography.

RESULTS

Twenty-four patients (20 males, mean age 75.6) were included. Primary technical success of proximal seal zones and CLEVAR deployment (no type 1/3 endoleaks, no conversion to open repair, AAA excluded and patient leaving theatre alive) was achieved in 100% of patients. All patients were alive and clinically stable at 3- and 12-month follow-up. There were five patients requiring re-intervention; at the 3-month follow-up, one patient (4.2%) developed a type 1b endoleak requiring graft limb extension, one patient developed a right common femoral artery dissection requiring open repair and one patient required a limb extension of the right iliac limb due to risk of developing a type 1b endoleak. At the 12-month follow-up, two patients required embolization of type 2 endoleaks and no patients demonstrated type 1 or type 3 endoleaks.Conclusions: In-hospital and post-operative 3- and 12-month clinical and angiographic outcomes demonstrate safety and efficacy with CLEVARs in treating unruptured AAAs with HNA. Further research involving larger heterogenous sample sizes is warranted to determine long-term clinical outcomes.

Five-year outcomes of endosuture aneurysm repair in patients with short neck abdominal aortic aneurysm from the ANCHOR registry

OBJECTIVE

Hostile aortic neck anatomies such as proximal short necks are known to put patients at an increased risk for type IA endoleaks, migration, and need for reinterventions. The Heli-FX EndoAnchor System was designed to improve seal of aortic stent grafts. Endosuture aneurysm repair (ESAR) using EndoAnchors with the Endurant stent graft has been shown to be safe and effective for the treatment of patients with short necks through one year. This study reports the 5-year patient outcomes of the Aneurysm Treatment using the Heli-FX EndoAnchor System Global Registry (ANCHOR) short neck regulatory cohort.

METHODS

The 70 patients from the ANCHOR Registry were cohort submitted to regulators for approval of the Endurant short neck indication. Patients had an infrarenal neck length of ≥ 4 mm and <10 mm. At 5 years, this short neck cohort had clinical and imaging follow-up compliance rates of 85% (28/33) and 70% (23/33), respectively.

RESULTS

The short neck cohort had a mean age of 71.3±8.1 years and was 27.1% (19/70) female. Kaplan Meier freedom from all-cause mortality was 68.5 ± 6.2%, freedom from aneurysm-related mortality was 90.1 ± 4.5%, freedom from any endovascular or surgical secondary procedure was 76.9 ± 7.2%, and freedom from rupture was 95.6 ± 3.2%. Eight patients had a total of nine type IA endoleaks detected through 5 years, of which three resolved spontaneously by the next follow-up visit. There were two patients with renal complications who did not undergo reintervention and there were no device migrations reported through 5 years. After 5 years, 68.2% of patients (15/22) had sac regression, 13.6% (3/22) had stable sacs, and 18.2% (4/22) had increased sac diameter as compared with their 1-month measurements.

CONCLUSIONS

After ESAR treatment using Heli-FX EndoAnchors with Endurant, the 5-year outcomes of the short neck cohort from the ANCHOR registry had encouraging results with regards to proximal neck-related complications, secondary procedures, and sac regression. This review of ESAR in patients with short proximal necks showed positive outcomes through 5 years although follow-up of a larger cohort is necessary.

Brazilian Society for Angiology and Vascular Surgery guidelines on abdominal aortic aneurysm

The Brazilian Society of Angiology and Vascular Surgery, through the Guidelines Project, presents new Abdominal Aortic Aneurysm Guidelines, on the subject of care for abdominal aortic aneurysm patients. Its development prioritized descriptive guidelines, using the EMBASE, LILACS, and PubMed databases. References include randomized controlled trials, systematic reviews, meta-analyses, and cohort studies. Quality of evidence was evaluated by a pair of coordinators, aided by the RoB 2 Cochrane tool and the Newcastle Ottawa Scale forms. The subjects include juxtarenal aneurysms, infected aneurysms, and new therapeutic techniques, especially endovascular procedures. The current version of the guidelines include important recommendations for the primary topics involving diagnosis, treatment, and follow-up for abdominal aortic aneurysm patients, providing an objective guide for medical practice, based on scientific evidence and widely available throughout Brazil.

The effect of stent graft curvature on the hemodynamic displacement force after abdominal aortic aneurysm endovascular repair

Endovascular aortic aneurysm repair is a minimally invasive procedure with low mortality and morbidity. Clinical studies have revealed that a displacement force (DF) can cause stent graft (SG) migration in some circumstances requiring repeated intervention. This study aims to determine the relationship between the SG curvature and the calculated DF from four patient-specific computational fluid dynamics models. The SG's curvature was defined according to the centrelines of the implanted SG's branches. The centrelines were defined as either intersecting or separated lines. The centreline curvature (CLC) metrics were calculated based on the local curvature radii and the distances from the centrelines of idealized straight branches. The average CLC value and average variation were calculated to represent the entire graft's curvature. These CLC calculations were compared, and the method that gave the best correlation to the calculated DF was found. The optimal correlation is obtained from calculating the CLC average variation using separated centrelines and distance from straight lines, with an R² = 0.89. Understanding the relationship between vascular morphology and DF can help identify at-risk patients before the procedure. In these cases, we can provide appropriate treatment and follow up with the patient to prevent future failure.

Comparative Effectiveness of Treatment Modalities for Complex Aortic Aneurysms: A Network Meta-Analysis of Observational Studies

BACKGROUND

To conduct a network meta-analysis comparing multiple treatments for complex aortic aneurysms (CAAs).

METHODS

Medical databases were searched on November 11, 2022. Twenty-five studies (5,149 patients) and four treatments (open surgery [OS], chimney/snorkel endovascular aneurysm repair [CEVAR], fenestrated endovascular aneurysm repair [FEVAR], and branched endovascular aneurysm repair) were selected. Outcomes were branch vessel patency, mortality, and reintervention at short- and long-term followup, and perioperative complications.

RESULTS

Regarding branch vessel patency, OS was the most effective treatment and had higher 24-month branch vessel patency rates than CEVAR (odds ratio [OR], 10.77; 95% confidence interval [CI], 2.08-55.79). FEVAR (OR, 0.52; 95% CI, 0.27-1.00) and OS (OR, 0.39; 95% CI, 0.17-0.93) were better than CEVAR regarding 30-day mortality and 24-month mortality, respectively. Regarding 24-month reintervention, OS was better than CEVAR (OR, 3.07; 95% CI, 1.15-8.18) and FEVAR (OR, 2.48; 95% CI, 1.08-5.73). Regarding perioperative complications, FEVAR had lower acute renal failure rates than OS (OR, 0.42; 95% CI, 0.27-0.66) and CEVAR (OR, 0.47; 95% CI, 0.25-0.92) and lower myocardial infarction rates than OS (OR, 0.49; 95% CI, 0.25-0.97) and was the most effective treatment in preventing acute renal failure, myocardial infarction, bowel ischemia, and stroke, while OS was the most effective treatment in preventing spinal cord ischemia.

CONCLUSIONS

OS might have advantages regarding branch vessel patency, 24-month mortality, and reintervention and is similar to FEVAR regarding 30-day mortality. Regarding perioperative complications, FEVAR might confer advantages in preventing acute renal failure, myocardial infarction, bowel ischemia, and stroke, and OS in preventing spinal cord ischemia.

Is Evar Feasible in Challenging Aortic Neck Anatomies? A Technical Review and Ethical Discussion

Background: Endovascular aneurysm repair (EVAR) has become an accepted alternative to open repair (OR) for the treatment of abdominal aortic aneurysm (AAA) despite “hostile” anatomies that may reduce its effectiveness. Guidelines suggest refraining from EVAR in such circumstances, but in clinical practice, up to 44% of EVAR procedures are performed using stent grafts outside their instruction for use (IFU), with acceptable outcomes. Starting from this “inconsistency” between clinical practice and guidelines, the aim of this contribution is to report the technical results of the use of EVAR in challenging anatomies as well as the ethical aspects to identify the criteria by which the “best interest” of the patient can be set. Materials and Methods: A literature review on currently available evidence on standard EVAR using commercially available endografts in patients with hostile aortic neck anatomies was conducted. Medline using the PubMed interface and The Cochrane Library databases were searched from 1 January 2000 to 6 May 2021, considering the following outcomes: technical success; need for additional procedures; conversion to OR; reintervention; migration; the presence of type I endoleaks; AAA-related mortality rate. Results: A total of 52 publications were selected by the investigators for a detailed review. All studies were either prospective or retrospective observational studies reporting the immediate, 30-day, and/or follow-up outcomes of standard EVAR procedures in patients with challenging neck anatomies. No randomized trials were identified. Fourteen different endo-grafts systems were used in the selected studies. A total of 45 studies reported a technical success rate ranging from 93 to 100%, and 42 the need for additional procedures (mean value of 9.04%). Results at 30 days: the incidence rate of type Ia endoleak was reported by 37 studies with a mean value of 2.65%; 31 studies reported a null migration rate and 32 a null conversion rate to OR; in 31 of the 35 studies that reported AAA-related mortality, the incidence was null. Mid-term follow-up: the incidence rate of type Ia endoleak was reported by 48 studies with a mean value of 6.65%; 30 studies reported a null migration rate, 33 a null conversion rate to OR, and 28 of the 45 studies reported that the AAA-related mortality incidence was null. Conclusions: Based on the present analysis, EVAR appears to be a safe and effective procedure—and therefore recommendable—even in the presence of hostile anatomies, in patients deemed unfit for OR. However, in order to identify and pursue the patient’s best interest, particular attention must be paid to the management of the patient’s informed consent process, which—in addition to being an essential ethical-legal requirement to legitimize the medical act—ensures that clinical data can be integrated with the patient’s personal preferences and background, beyond the therapeutic potential of the proposed procedures and what is generically stated in the guidelines.

Can We Still Teach Open Repair of Abdominal Aortic Aneurysm in The Endovascular Era? Single-Center Analysis on The Evolution of Procedural Characteristics Over 15 Years

OBJECTIVE

In many vascular centers an endovascular first policy for the treatment of abdominal aortic aneurysms (AAA) has resulted in endovascular aortic repair (EVAR) outnumbering open aortic repair (OAR). The declining routine in OAR raises the question whether this might influence procedural outcomes and diminish surgical expertise for current and future vascular surgeons. We aimed to analyze OAR outcomes, AAA morphology and procedural details over the past 15 years while an endovascular first approach was successively implemented.

PARTICICPANTS AND DESIGN

All patients operated for (i)ntact infra-/juxtarenal AAA between January 1, 2005 and December 31, 2019 were identified. Outcome parameters were length of stay (hospital/ICU), in-hospital mortality and medical/surgical complications. Operative details were clamping zone, access and graft configuration. AAA anatomy including neck and iliac parameters was analyzed with Endosize©. Logistic regression, uni- and multivariate analysis were applied.

RESULTS

293 patients received elective OAR for iAAA. Baseline characteristics (age, sex, hypertension, smoking, occlusive disease, coronary disease, hyperlipidemia, diabetes, renal insufficiency and obesity) did not change over time. The number of OAR dropped significantly (-0.5 cases/year p = 0.02). The procedure time (2005-2007: 192.2 ± 87.5min to 2017-2019: 235.6 ± 88.2min; p = 0.0001) and the length of stay (2005-2007: 12.0 ± 7.9 to 2017-2019: 17.0 ± 23.1; p = 0.03) increased significantly, whereas the in-hospital mortality, length of ICU stay and complication rates didn't, nor did AAA anatomy. Upon multivariate analysis, annual number of OAR and any additional anastomosis significantly influenced procedure time, trainee involvement, for example, did not. Hospital length-of-stay depended on patient age (p = 0.002), complication rates (p < 0.0001) and procedure time (p = 0.006).

CONCLUSION

Mortality and complication rates for OAR have remained low and constant. With the increase of EVAR, the absolute number of OARs has decreased significantly. However, the total procedure time has increased and depends significantly on the annual number of OARs in total and per surgeon. This might influence outcome parameters and should be implanted in future surgical education.

Editor's Choice - Comparison of Open, Standard, and Complex Endovascular Aortic Repair Treatments for Juxtarenal/Short Neck Aneurysms: A Systematic Review and Network Meta-Analysis

OBJECTIVE

Abdominal aortic aneurysms (AAAs) with adverse morphology of the aneurysm neck are "complex". Techniques employed to repair complex aneurysms include open surgical repair (OSR) and a number of on label endovascular techniques such as fenestrated endovascular aneurysm repair (FEVAR) and endovascular aneurysm repair (EVAR) with adjuncts (including chimneys and endo-anchors), as well as off label use of standard EVAR. The aim was to conduct a network meta-analysis (NMA) of published comparative outcomes.

DATA SOURCES

An electronic search was performed in Embase, MEDLINE, and the Cochrane Central Register of Controlled Trials (CENTRAL). These databases were interrogated using the PubMed interface and the Healthcare Databases Advanced Search (HDAS) interface developed by the National Institute of Health and Care Excellence.

REVIEW METHODS

Online databases were interrogated up to April 2020. Studies were included if they compared outcomes between at least two methods of repair for complex aneurysms (those with at least one adverse neck feature: absent/short neck, conicality, angulation, calcification, large diameter, and thrombus). The primary outcome measure was peri-operative death. Pre-registration was done in PROSPERO (CRD42020177482).

RESULTS

The search identified 24 observational studies and 7854 patients who underwent OSR, FEVAR, off label EVAR, or chimney EVAR. No comparative studies included EVAR with endo-anchors. NMA was performed on 23 studies that reported outcomes of aneurysms with short/absent infrarenal neck. Compared with OSR, off label EVAR (relative risk [RR] 0.10, 95% confidence interval [CI] 0.01 - 0.41) and FEVAR (RR 0.62, 95% CI 0.32-0.94) were associated with lower peri-operative mortality. This difference was not seen at the midterm follow up (30 months). Compared with OSR, FEVAR was associated with a lower peri-operative myocardial infarction (MI) rate (RR 0.37, 95% CI 0.16 - 0.62) but a higher midterm re-intervention rate (hazard ratio 1.65, 95% CI 1.04 - 2.66). All studies had a "moderate" or "high" risk of bias. Confidence in the network findings (GRADE) was generally "low".

CONCLUSION

This NMA demonstrated a peri-operative survival benefit for off label EVAR and FEVAR compared with OSR, potentially due to reduced risk of MI. FEVAR carries a greater midterm re-intervention risk than OSR, with potential implications for cost effectiveness. There is paucity of comparative data for cases with adverse neck features other than short length.

The Polymer-Based Technology in the Endovascular Treatment of Abdominal Aortic Aneurysms

An abdominal aortic aneurysm (AAA) is a dilatation of the abdominal aorta that progressively grows until it ruptures. Treatment is typically recommended when the diameter is more than 5 cm. The EVAR (Endovascular aneurysm repair) is a minimally invasive procedure that involves the placement of an expandable stent graft within the aorta to treat aortic disease without operating directly on the aorta. For years, stent grafts' essential design was based on metallic stent frames to support the fabric. More recently, a polymer-based technology has been proposed as an alternative method to seal AAA. This review underlines the two platforms that are based on a polymer technology: (1) the polymer-filled endobags, also known as Endovascular Aneurysm Sealing (EVAS) with Nellix stent graft; and (2) the O-ring EVAR polymer-based proximal neck sealing device, also known as an Ovation stent graft. Polymer characteristics for this particular aim, clinical applications, and durability results are hereby summarized and commented critically. The technique of inflating endobags filled with polymer to exclude the aneurysmal sac was not successful due to the lack of an adequate proximal fixation. The platform that used polymer to create a circumferential sealing of the aneurysmal neck has proven safe and effective.

Editor's Choice - Influence of Proximal Aortic Neck Diameter on Durability of Aneurysm Sealing and Overall Survival in Patients Undergoing Endovascular Aneurysm Repair. Real World Data from the Gore Global Registry for Endovascular Aortic Treatment (GREAT)

OBJECTIVES

Aortic neck diameter is an independent anatomical feature that is poorly understood, yet potentially linked to proximal seal failure and adverse outcome following standard EVAR. The aim of this study was to assess whether large proximal aortic neck (LAN) diameter is associated with adverse outcome using prospectively collected individual patient data from The Global Registry for Endovascular Aortic Treatment (GREAT).

METHODS

A total of 3166 consecutive patients, from 78 global centres, receiving Gore Excluder stent grafts for infrarenal abdominal aortic aneurysm repair between 2011 and 2017 were included. Patient demographics, biometrics, operative details, and clinical outcome were analysed. Patients were divided into two groups: normal baseline proximal aortic neck (NAN) diameter (<25 mm on computed tomography aortography), and LAN (≥25 mm). Clinical follow up (including imaging) was available for 76.5% of patients 5 years post-intervention. Primary endpoints analysed were Type IA endoleak and any aortic re-intervention up to 5 years post-procedure. A composite endpoint of Type IA endoleak, re-intervention, aortic rupture, or aortic related mortality was also assessed.

RESULTS

A total of 1977 (62.4%) patients were classified NAN and 1189 (37.6%) were LAN. Immediate technical success was achieved in 3164 out of 3166 (>99.9%) of cases. Freedom from Type IA endoleak was achieved in 99.3% at 1 year and 97.3% at 5 years (lower in LAN vs. NAN: 96.8% [CI 93.7-98.4] vs. 98.6% [CI 94.5-99.6], p = .007). Freedom from aortic re-intervention was 93.7% at 1 year and 83.2% at 5 years (78.6% [CI 66.0-87.0] LAN vs. 86.0% [CI 81.8-89.3] NAN, p = .11). Freedom from primary composite endpoint was 95.9% at 1 year and 84.9% at 5 years (81.3% [CI 69.2-89.0] LAN vs. 87.0% [CI 81.6-91.0] NAN, p = .066). Five year survival was lower in the LAN group; 64.6% (CI 50.1-75.7) vs. 76.5% (CI 70.7-81.3), p = .03).

CONCLUSION

LAN is associated with delayed Type IA endoleak occurrence and lower overall survival.

What Did Endovascular Aortic Repair Bring for the Treatment Strategy of Abdominal Aortic Aneurysm?

Objective: We examined the effects of the introduction of endovascular aortic repair (EVAR) on treatment for abdominal aortic aneurysms (AAAs).

Subjects: We compared patients in the following three periods: period I (January 2002–December 2006, 105 patients), period II (January 2007–December 2011, 242 patients, duration of 5 years after the introduction of EVAR), and period III (January 2012–December 2016, 237 patients, duration of 5 years after period II). We used the American Society of Anesthesiologists (ASA) classification for risk assessment.

Results: In the Open repair (OR) group, the incidences of ASA class 2 increased and classes 3 and 4 decreased significantly in periods II and III compared with period I. In all periods, there were no in-hospital deaths. Suprarenal aortic cross-clamping was required in 18 patients (19.1%) in period III and 5 patients (6.3) in period I, and the difference was significant (P<0.05). In the EVAR group, no differences in age, sex, or ASA classification class were observed between periods II and III. In period II, one patient died due to aneurysm rupture during surgery. Significant differences were observed when comparing both groups in periods II and III: patients in the EVAR group were older (P<0.01) and the OR group had a higher proportion of ASA class 2 patients and the EVAR group had a higher proportion of ASA class 3 or 4 patients (P<0.01). Among all AAA surgeries, rupture occurred in 25 patients (23.8%) in period I, 18 patients (7.4) in period II, and 16 patients (6.8) in period III. The number of ruptures was significantly lower in periods II and III than in period I (P<0.01).

Conclusions: The findings of this study suggest that EVAR should be indicated for high-risk patients and had the good outcome of AAA treatment. (This is a translation of Jpn J Vasc Surg 2018; 27: 27–32.)

Midterm Single-Center Results of Endovascular Aneurysm Repair With Additional EndoAnchors

PURPOSE

To review midterm clinical outcomes of EndoAnchor placement during or after endovascular aneurysm repair (EVAR) or chimney EVAR (ch-EVAR).

MATERIALS AND METHODS

A retrospective analysis was conducted of 51 consecutive patients [median age 75 years; 38 men] who underwent EVAR/ch-EVAR with EndoAnchor placement between June 2010 and December 2016 to prevent seal failures (31, 61%) or to treat type Ia endoleak and/or migration (20, 39%). Median aortic neck diameter was 27.7 mm and median neck length was 9.0 mm. Thirty-three (65%) had a conical neck; 48 (94%) had at least 1 hostile neck characteristic. Thirty-two (63%) patients had severe comorbidities (ASA score ⩾III). Eight patients had a single ch-EVAR procedure. Baseline patient characteristics, anatomic variables, procedure details, early and late complications, reinterventions, and aneurysm-related and all-cause mortality rates were recorded. Follow-up imaging was performed with computed tomography angiography (CTA) or duplex ultrasonography.

RESULTS

Median procedure time was 100 minutes; a median of 6 EndoAnchors were implanted. There were 10 (10%) residual type Ia endoleaks at the end of the procedure; 9 had resolved by the first postoperative CTA. One residual and 2 new type Ia endoleaks were identified at the first postoperative imaging. Median follow-up for the entire cohort was 24.0 months, during which 3 new type Ia endoleaks were identified. Five of the 6 type Ia endoleaks were treated, 1 resolved spontaneously. There was 1 endograft limb occlusion without clinical consequences, 1 chimney graft occlusion without possibilities for a reintervention, 1 rupture after type IV endoleak (a Nellix device was successfully deployed within the main device), and 1 complete graft explantation for infection. There was no new-onset hemodialysis. Kaplan-Meier estimates of freedom from type Ia endoleak, proximal neck-related reinterventions, and aneurysm-related mortality at 2 years were 87.3%, 92.2%, and 94.0%, respectively.

CONCLUSION

EndoAnchors are helpful in the endovascular treatment of unfavorable proximal aortic necks, with fair midterm results.

Early results with the custom-made Fenestrated Anaconda aortic cuff in the treatment of complex abdominal aortic aneurysm

OBJECTIVE

The objective of this study was to investigate the feasibility of a specific custom-made fenestrated aortic cuff in the treatment of complex abdominal aortic aneurysms (AAAs).

METHODS

Between 2013 and 2016, a total of 57 custom-made Fenestrated Anaconda (Vascutek, Inchinnan, Scotland, UK) aortic cuffs were placed in 38 centers worldwide. All centers were invited to participate in this retrospective analysis. Postoperative and follow-up data included the presence of adverse events, necessity for reintervention, and renal function.

RESULTS

Fifteen clinics participated, leading to 29 cases. Median age at operation was 74 years (interquartile range [IQR], 71-78 years); five patients were female. Two patients were treated for a para-anastomotic AAA after open AAA repair, 19 patients were treated because of a complicated course after primary endovascular AAA repair, and 8 cases were primary procedures for AAA. A total of 76 fenestrations (mean, 2.6 per case) were used. Four patients needed seven adjunctive procedures. Two patients underwent conversion, one because of a dissection of the superior mesenteric artery and one because of perforation of a renal artery. Median operation time was 225 minutes (IQR, 150-260 minutes); median blood loss, 200 mL (IQR, 100-500 mL); and median contrast volume, 150 mL (IQR, 92-260 mL). Primary technical success was achieved in 86% and secondary technical success in 93%. The 30-day morbidity was 7 of 29 with a mortality rate of 4 of 29. Estimated glomerular filtration rate remained unchanged before and after surgery (76 to 77 mL/min/m²). Between preoperative and median follow-up of 11 months, estimated glomerular filtration rate was reduced statistically significantly (76 to 63 mL/min/m²). During follow-up, 9 cases had an increase in aneurysm sac diameter (5 cases >5 mm); 14 cases had a stable or decreased aneurysm sac diameter; and in 2 cases, no aneurysm size was reported. No type I endoleak was reported, and two cases with a type III endoleak were treated by endovascular means during follow-up. Survival, reintervention-free survival, and target vessel patency at 1 year were 81% ± 8%, 75% ± 9%, and 99% ± 1%, respectively. After 2 years, these numbers were 81% ± 8%, 67% ± 11%, and 88% ± 6%, respectively. During follow-up, the two patients with a type III endoleak needed endograft-related reinterventions.

CONCLUSIONS

Treatment with this specific custom-made fenestrated aortic cuff is feasible after complicated previous (endovascular) aortic repair or in complex AAAs. The complexity of certain AAA cases is underlined in this study, and the Fenestrated Anaconda aortic cuff is a valid option in selected cases in which few treatment options are left.

Decision uncertainty and value of further research: a case-study in fenestrated endovascular aneurysm repair for complex abdominal aortic aneurysms

Background

Fenestrated endovascular aneurysm repair (fEVAR) is a new approach for complex abdominal aortic aneurysms, limited to a few specialist centers, with limited evidence base. We developed a cost-effectiveness decision model of fEVAR compared to open surgical repair (OSR) to investigate the likely direction of costs and benefits and inform further research projects on this technology.

Methods

A systematic review with meta-analysis and a four-state Markov model were used to estimate the cost-effectiveness of fEVAR versus OSR. We used a recent coverage with evidence development framework to characterize the main sources of uncertainty and inform decisions about the type of further research that would be most worthwhile and feasible.

Results

Seven observational comparative studies were identified, of which four presented odds ratios adjusted for confounders. The odds ratios for operative mortality varied widely between studies. Assuming a central estimate of the odds ratio of 0.54 (95% CI 0.05–6.24), the decision model estimated that the incremental cost per quality adjusted life year (QALY) was £74,580/QALY with a probability of 9 and 16% of being cost-effective at standard cost-effectiveness thresholds of £20,000/QALY and £30,000/QALY, respectively. The Expected Value of Perfect Information over 10 years at a threshold of £20,000/QALY was £11.2 million. Operative mortality contributed to most of the uncertainty in the decision model.

Conclusions

In the case of “maturing technologies”, decision modelling indicates the likely direction of costs and benefits and guides the development of further research projects. In our analysis of fEVAR versus OSR, decision uncertainty, particularly around operative mortality, might be effectively resolved by a short-term RCT, or possibly a well-conducted comparative observational study. Decision makers may consider that a conditional coverage decision is warranted with assessments required to make this type of recommendation depending on local priorities and circumstances.

Electronic supplementary material

The online version of this article (10.1186/s12962-018-0098-7) contains supplementary material, which is available to authorized users.

Clinical Outcomes of Endovascular Aneurysm Repair with the Kilt Technique for Abdominal Aortic Aneurysms with Hostile Aneurysm Neck Anatomy: A Korean Multicenter Retrospective Study

PURPOSE

We aimed to evaluate the clinical efficacy and short-term clinical outcomes of Kilt technique-based endovascular aneurysm repair (EVAR) with Seal^® stent-grafts for abdominal aortic aneurysms (AAAs) with hostile neck anatomy (angle > 60°).

MATERIALS AND METHODS

We retrospectively evaluated the pre-EVAR and follow-up computed tomography angiography findings of 24 patients (mean age 71 ± 11 years; age range 32-87 years; mean follow-up 50 ± 12 months) with hostile neck AAAs treated between 2010 and 2015. Serial change in aneurysmal neck angle was calculated using a standardized protocol. Relationships between clinical variables and outcomes were evaluated using univariate and multivariate Cox analyses and mixed-model regression. In addition, the Kaplan-Meier method was used to assess the cumulative rates of survival, endoleak, and reintervention.

RESULTS

The primary technical success rate (success within 24 h after EVAR) was 100% (24/24). The survival rate was 96 ± 8% at 1 month, 6 months, 1 year, and 3 years, and 87 ± 18% at 5 years. Endoleaks occurred in three patients. Four reinterventions were performed in three patients; no surgical revisions were required. Causes of post-EVAR mortality included intracerebral hemorrhage at 14 days and rhabdomyolysis at 32 months. The most remarkable change after Kilt-based EVAR was an acute decrease in the neck angle, which was observed between the pre-EVAR and first follow-up visits (at 1 month) (P = 0.001).

CONCLUSION

Kilt-based EVAR with Seal^® stent-grafts for AAAs with a severely angulated neck (angle > 60°) provided high technical success, low mortality, and low complication rates during short-term follow-up.

Morphological and Biomechanical Features in Abdominal Aortic Aneurysm with Long and Short Neck-Case-Control Study in 64 Abdominal Aortic Aneurysms

BACKGROUND

Both, open and endovascular, procedures are related to higher complication rate in abdominal aortic aneurysm (AAA) with shorter neck. Previous study showed that long-neck AAA might have lower risk of rupture. Estimation of biomechanical forces in AAA improves rupture risk assessment. The aim of this study was to compare morphological features and biomechanical forces in the short- and long-neck AAA with threshold of 15 mm.

METHODS

Digital Imaging and Communication in Medicine images of 64 aneurysms were prospectively collected and analyzed in a case-control study. Using commercially available software, Peak wall Stress (PWS) and Rupture Risk Equivalent Diameter (RRED) were determined. Difference between the maximal aneurysm diameter (MAD) and RRED was calculated and expressed as an absolute and relative (percentage of the MAD) value. In addition, volume of intraluminal thrombus (ILT) was calculated and expressed relative to AAA volume.

RESULTS

Study included 64 AAA divided in group with long (36, 56.25%), and short (28, 43.75%) neck. There was no correlation between neck length and MAD, PWS, and RRED (P = 0.646, P = 0.421, and P = 0.405, respectively). Relative ILT volume was greater in the short-neck aneurysms (P = 0.033). Relative difference between RRED and MAD was -4% and -14.8% in short- and long-neck aneurysms, respectively (P = 0.029). The difference between RRED and MAD was positive in 14/28 patients (50%) with short neck and in 6/35 patients (17.14%) with long neck (P = 0.011).

CONCLUSIONS

Based on our biomechanical analysis, in AAA with neck longer than 15 mm rupture risk might be lower than the risk estimated by its diameter. It might be explained with lower relative volume of ILT.

Fenestrated and Branched Aortic Grafts

BACKGROUND

Abdominal and thoracic aortic aneurysms are diagnosed in 40 and 10 to 15 out of 100 000 persons per year, respectively. Fenestrated (fEVAR) and branched (bEVAR) stent grafts have been developed for abdominal juxtarenal and thoracoabdominal aneurysms. We discuss the patency and complication rates of fEVAR and bEVAR procedures and compare them with the outcome of open surgery.

METHODS

This review is based on pertinent publications from 2011 to 2014 that were retrieved by a selective literature search. The clinical outcomes of case series involving a total of more than 1500 patients are presented. The discussion takes account of recommendations contained in the literature and the authors' own experience.

RESULTS

Open surgery and aortic stent grafting have not been compared in any randomized trial to date. We identified 7 clinical series that included a total of 1270 fEVAR patients and 5 with a total of 408 bEVAR patients. The perioperative mortality after fEVAR procedures was 0-4%. Spinal cord ischemia arose in 1% of cases. The stent patency rate in visceral vessels ranged from 93 to 98%. bEVAR procedures were associated with both higher mortality (4-7%) and more common spinal cord ischemia (4-13%). 5-8% of all patients needed dialysis perioperatively, and the stent patency rate in visceral vessels was 94-97%. Preoperative renal insufficiency was a risk factor for peri-interventional death. Impaired renal function after fEVAR/bEVAR procedures was mainly associated with intermittent lower limb ischemia.

CONCLUSION

The results of fEVAR/bEVAR procedures in the last 5 years are similar to those of open surgery. The high postoperative rate of spinal cord ischemia remains a serious problem in the endovascular treatment of thoracoabdominal aortic aneurysms. The decision to implant a stent graft by an endovascular approach or to treat surgically should be made on a case-to-case basis in an interdisciplinary vascular conference.

Snorkel endovascular abdominal aortic aneurysm repair versus fenestrated endovascular aneurysm repair: is it a competition?

The endovascular treatment of juxtarenal abdominal aortic aneurysm (AAA) can be performed by either a standard endovascular stent graft with additional snorkle grafts to aorta branches (snorkel endovascular aneurysm repair) or implantation of a fenestrated stent graft (fenestrated endovascular aneurysm repair). While many vascular surgeons consider snorkel endovascular aneurysm repair and fenestrated endovascular aneurysm repair to be competing techniques or alternate strategies, published procedural outcomes suggest more complementary roles. In this clinical review, the advantages and disadvantages of these two approaches are debated, as much can be learned from both strategies. Because the indications and circumstances for juxtarenal AAA repair vary based on patient-specific comorbidities and anatomy, it is recommended that vascular surgeons have access to, and experience with, both treatment strategies. Based on published outcomes, patient outcomes, stent-graft patency, and re-intervention rates are generally similar and acceptable compared with open AAA repair. We conclude that there is a time and a place for both snorkel endovascular aneurysm repair and fenestrated endovascular aneurysm repair for the endovascular management of juxtarenal and pararenal AAA anatomy.

Results of open pararenal abdominal aortic aneurysm repair: single centre series and pooled analysis of literature

Objectives Endovascular treatment of pararenal abdominal aortic aneurysm has gained terrain over the past decade, despite the substantial need for reinterventions during follow-up. However, open repair is still a well-established treatment option. With the current study we report the results of a consecutive series of elective primary open pararenal abdominal aortic aneurysm repair in a tertiary vascular referral centre, combined with an overview of current literature and pooled data analysis of perioperative mortality of open and endovascular pararenal abdominal aortic aneurysm repair. Methods A retrospective analysis of a prospective database of all elective open pararenal abdominal aortic aneurysm repairs in the St. Antonius Hospital between 2005 and 2014 was performed. Primary endpoint was 30-day mortality. Secondary endpoints were 30-day morbidity, new onset dialysis, reintervention free survival, and overall survival during follow-up. Results Between 2005 and 2014, 214 consecutive patients underwent elective open pararenal abdominal aortic aneurysm repair. Mean age was 69.8 (±7.1) years, 82.7% (177/214) were men, and mean abdominal aortic aneurysm diameter was 62 (±11) mm. Thirty-day mortality was 3.4%. Thirty-day morbidity was 27.1%, which predominantly consisted of pneumonia (18.7% (40/214)), cardiac events (3.3% (7/214)), and new onset dialysis (2.8% (6/214)). Estimated five-year overall survival rate was 74.2%. 0.9% (2/214) of patients required abdominal aortic aneurysm-related reintervention, and an additional 2.3% (5/214) required surgical repair of an incisional hernia. Pooled analysis of literature revealed a 30-day mortality of 3.0% for open pararenal repair and 1.9% for fenestrated endovascular repair. Conclusion Open pararenal abdominal aortic aneurysm repair in the era of increasing endovascular options results in acceptable perioperative morbidity and mortality rates. Mid-term reintervention rate is low compared to fenestrated endovascular aneurysm repair. Expertise with open repair still remains essential for treatment of pararenal abdominal aortic aneurysms in the near future, especially for those patients that are declined for endovascular treatment.

Fenestrated stent grafts for the treatment of complex aortic aneurysm disease: A mature treatment paradigm

The introduction of fenestrated stent grafts (SGs) to treat abdominal aortic aneurysms (AAAs) with short proximal necks began in 1999. Nowadays, the whole visceral aorta can be treated totally by endovascular means. The established use of fenestrated devices to treat complex AAAs as a first-line management option has been previously reported. An up-to-date evaluation of the literature was performed including all types of publications regarding the use of fenestrated technology to repair complex AAAs. Fenestrated repair is now an established alternative to hybrid/chimney/snorkel repairs. However, specific criteria and prerequisites are required for the use and improvement of this method. Multiple device morphologies have been used incorporating the visceral arteries in various combinations. This modular strategy connects different devices (bridging covered stents and bifurcated SGs) with the aortic main body, thus excluding the aneurysm from the circulation. Precise deployment of the fenestrated SG is mandatory for successful visceral vessel revascularization. Accurate SG sizing and customization, a high level of technical skill, and facilities with modern imaging techniques including 3D road mapping and dedicated hybrid rooms are required. Most experience has been with the custom-made Zenith Cook platform, although off-the-shelf devices have been recently implanted. More complex repairs have been performed over the last few years, but device complexity has also increased. Perioperative, mid-term, and a few recently reported long-term results are encouraging. Secondary interventions remain the main problem, similar to that observed after traditional endovascular abdominal aortic aneurysm repair (EVAR).

Impact of Fenestrated Endovascular Abdominal Aortic Aneurysm Repair on Renal Function

Purpose: To investigate the impact of fenestrated endovascular aneurysm repair (fEVAR) on renal function perioperatively and at midterm. Methods: A case-controlled study was performed involving 58 patients (mean age 75±7 years; 51 men) who underwent elective fEVAR for a juxtarenal or short-necked abdominal aortic aneurysm (AAA) matched on age, sex, smoking, diabetes, and baseline estimated glomerular filtration rate (eGFR) with a contemporaneous group undergoing open aneurysm repair (OAR) for the same indications. Perioperative incidence of acute kidney injury (AKI) and levels of eGFR at 30 days and 1 year were compared. A systematic literature review was performed to identify studies that had used eGFR as renal outcome after fEVAR; the pooled data were meta-analyzed using an eGFR drop >30% at 1 month and the latest follow-up as endpoints. Results are reported as the pooled proportion and 95% confidence interval (CI). Results: The incidence of AKI after fEVAR was 28% compared to 10% after OAR (p=0.03). Following fEVAR, the mean eGFR dropped from 78±8 to 74±9 mL/min/1.73 m2 at 30 days compared to a change from 79±8 to 80±16 mL/min/1.73 m2 after OAR (p<0.01). However, the absolute drop in eGFR between fEVAR and OAR at 1 year was similar (7 mL/min/1.73 m2; p=0.53); 7% of the fEVAR patients had an eGFR drop >30% at that point compared with none for OAR (p=0.12). The systematic literature review identified eGFR outcomes for 193 fEVAR patients. Combining these patients with the 58 from our cohort study, the pooled proportions of eGFR drop >30% were 20% (95% CI 9% to 39%) at 30 days and 8% (95% CI 0.5% to 13%) at the end of follow-up. Conclusion: fEVAR has a significant perioperative impact on renal function, but 1-year results are similar to OAR. fEVAR patients may benefit from targeted AKI prevention strategies that need to be assessed in relevant studies.

The use of fenestrated and branched endovascular aneurysm repair for juxtarenal and thoracoabdominal aneurysms: a systematic review and cost-effectiveness analysis

BACKGROUND

Patients with large abdominal aortic aneurysms (AAAs) are usually offered reparative treatment given the high mortality risk. There is uncertainty about how to treat juxtarenal AAAs (JRAAAs) or thoracoabdominal aortic aneurysms (TAAAs). Endovascular repair of an abdominal aortic aneurysm (EVAR) is often seen as safer and easier than open surgical repair (OSR). However, endovascular treatment of JRAAAs or TAAAs requires specially manufactured stent grafts, with openings to allow blood to reach branches of the aorta. Commissioners are receiving increasing requests for fenestrated EVAR (fEVAR) and branched EVAR (bEVAR), but it is unclear whether or not the extra cost of fEVAR or bEVAR is justified by advantages for patients.

OBJECTIVE(S)

To assess the clinical effectiveness, safety and cost-effectiveness of fEVAR and bEVAR in comparison with conventional treatment (i.e. no surgery) or OSR for two populations: JRAAAs and TAAAs.

DATA SOURCES

Resources were searched from inception to October 2013, including MEDLINE (OvidSP), EMBASE (OvidSP) and the Cochrane Central Register of Controlled Trials (Wiley) and, additionally, for cost-effectiveness, NHS Economic Evaluation Database (NHS EED; Wiley) and EconLit (EBSCOhost). Conference abstracts were also searched.

REVIEW METHODS

Studies were included based on an intervention of either fEVAR or bEVAR and a comparator of either OSR or no surgery. For clinical effectiveness, observational studies were excluded only if they were not comparative, i.e. explicitly selected on the basis of prognosis.

RESULTS

For clinical effectiveness, searches retrieved 5253 records before deduplication. Owing to overlap between the databases, 1985 duplicate records were removed. Of the remaining 3268 records, based on titles and abstracts, 3244 records were excluded, leaving 24 publications to be ordered. All 24 studies were excluded as none of them satisfied the inclusion criteria. Sixteen studies were excluded on study design, six on intervention and two on comparator. Five out of 16 studies excluded on study design reported a comparison. However, all of the studies acknowledged that they had groups that were not comparable at baseline given that they had selectively assigned younger, fitter patients to OSR. Therefore, these studies were considered 'non-comparative'. For cost-effectiveness, searches identified 104 references before deduplication. Owing to overlap between the databases, 34 duplicate records were removed. Of the remaining 70 records, seven were included for the full assessment based on initial screening. After a full-text review, no studies were included. Because of the lack of clinical effectiveness evidence and difficulty in estimating costs given the rapidly changing and variable technology, a cost-effectiveness analysis (CEA) was not performed. Instead a detailed description of modelling methods was provided.

CONCLUSIONS

Despite a thorough search, no studies could be found that met the inclusion criteria. All studies that compared either fEVAR or bEVAR with either OSR or no surgery explicitly selected patients based on prognosis, i.e. essentially the populations for each comparator were not the same. Despite not being able to conduct a CEA, we have provided detailed methods for the conduct if data becomes available.

FUTURE WORK

We recommend at least one clinical trial to provide an unbiased estimate of effect for fEVAR/bEVAR compared with OSR or no surgery. This trial should also collect data for a CEA.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42013006051.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Editor's choice - thirty day outcomes and costs of fenestrated and branched stent grafts versus open repair for complex aortic aneurysms

OBJECTIVE

To compare 30 day outcomes and costs of fenestrated and branched stent grafts (f/b EVAR) and open surgery (OSR) for the treatment of complex abdominal aortic aneurysms (AAA) and thoraco-abdominal aortic aneurysms (TAAA).

METHODS

The multicenter prospective registry WINDOW was set up to evaluate f/b EVAR in high risk patients with para/juxtarenal AAA, and infradiaphragmatic and supradiaphragmatic TAAA. A control group of patients treated by OSR was extracted from the national hospital discharge database. The primary endpoint was 30 day mortality. Secondary endpoints included severe complications, length of stay, and costs. Mortality was assessed by survival analysis and uni/multivariate Cox regression analyses using pre- and post-operative characteristics. Bootstrap methods were used to estimate the cost-effectiveness of f/b EVAR versus OSR.

RESULTS

Two hundred and sixty eight cases and 1,678 controls were included. There was no difference in 30 day mortality (6.7% vs. 5.4%, p = 0.40), but costs were higher with f/b EVAR (€38,212 vs. €16,497, p < .001). After group stratification, mortality was similar with both treatments for para/juxtarenal AAA (4.3% vs. 5.8%, p = .26) and supradiaphragmatic TAAA (11.9% vs. 19.7%, p = .70), and higher with f/b EVAR for infradiaphragmatic TAAA (11.9% vs. 4.0%, p = .010). Costs were higher with f/b EVAR for para/juxtarenal AAA (€34,425 vs. €14,907, p < .0001) and infradiaphragmatic TAAA (€37,927 vs. €17,530, p < .0001), but not different for supradiaphragmatic TAAA (€54,710 vs. €44,163, p = .18).

CONCLUSION

f/b EVAR does not appear justified for patients with para/juxtarenal AAA and infradiaphragmatic TAAA fit for OSR but may be an attractive option for patients with para/juxtarenal AAA not eligible for surgery and patients with supradiaphragmatic TAAA.

CLINICAL TRIAL REGISTRATION

http://www.clinicaltrials.gov/ct2/show/NCT01168037; identifier: NCT01168037 (WINDOW registry).

Open versus Endovascular Repair of Abdominal Aortic Aneurysm in the Elective and Emergent Setting in a Pooled Population of 37,781 Patients: A Systematic Review and Meta-Analysis

Background. We evaluated the incidence of mortality and myocardial infarction (MI) in endovascular repair (EVAR) as compared to open aneurysm repair (OAR) in both elective and ruptured abdominal aortic aneurysm (AAA ) setting. Methods. We analyzed the rates of 30-day mortality, 30-day MI, and hospital length of stay (LOS) based on comparative observation and randomized control trials involving EVAR and OAR. Results. 41 trials compared EVAR to OAR with a total pooled population of 37,781 patients. Analysis of elective and ruptured AAA repair favored EVAR with respect to 30-day mortality with a pooled odds ratio of 0.19 (95% CI 0.17–0.20; I² = 88.9%; P < 0.001). There were a total of 1,835 30-day MI events reported in the EVAR group as compared to 2,483 events in the OAR group. The pooled odds ratio for elective AAA was 0.74 (95% CI 0.58–0.96; P = 0.02) in favor of EVAR. The average LOS was reduced by 296.75 hrs (95% CI 156.68–436.82 hrs; P < 0.001) in the EVAR population. Conclusions. EVAR has lower rates of 30-day mortality, 30-day MI, and LOS in both elective and ruptured AAA repair.

Treatment of Hostile Proximal Necks During Endovascular Aneurysm Repair

Endovascular aneurysm repair (EVAR) is a therapy that continues to evolve rapidly as advances in technology are incorporated into new generations of devices and surgical practice. Although EVAR has emerged as a safe and effective treatment for patients with favorable anatomy, treatment of patients with unfavorable anatomy remains controversial and is still an off-label indication for endovascular treatment with some current stent-grafts. The proximal neck of the aneurysm remains the most hostile anatomic barrier to successful endovascular repair with long-term durability. Open surgery for unfavorable necks is still considered the gold standard treatment in contemporary practice, despite the increased mortality and morbidity attributed to suprarenal cross-clamping, particularly in high-risk patients. Evolving technology may overcome the obstacles preventing endovascular treatment of unfavorable proximal neck anatomy; current approaches include purely endovascular as well as hybrid approaches, and generally include strategies that either extend the length of the short neck, move the proximal neck more proximally, or keep the short neck intact. These approaches include the use of debranching techniques, banding, chimneys, fenestrated and branched devices, filling the sac with endobags, endoanchors, and other novel devices. These newer-generation devices appear to have promising short- and midterm results. However, lack of good evidence of efficacy with long-term results for these newer approaches still precludes wide dissemination of endovascular solutions for the hostile proximal neck.

Innovative application of available stent grafts in Japan in aortic aneurysm treatment-significance of innovative debranching and chimney method and coil embolization procedure

OBJECTIVE

We here describe our experience with innovative uses of these devices.

PATIENTS AND METHODS

We reviewed treatment outcomes of 310 endovascular abdominal aortic repair (EVAR) and 83 thoracic endovascular aortic repair (TEVAR) cases performed between August 2007 and February 2012. We separately assessed results in elderly and high-risk patients who had a novel procedure. This group included 94 patients who underwent EVAR with IIA embolization, 10 patients who had EVAR and a renal artery chimney procedure for a short aortic neck, 20 patients who had two de-branching TEVAR or Chimney method for thoracic aortic aneurysms (TAA) and 3 patients who had debranching TEVAR for thoracic abdominal aortic aneurysms (TAAA).

RESULTS

Of the 393 patients given stent grafts (SGs), 3 (0.8%) died in the hospital, including 1 patient with pneumonia who underwent EVAR and IIA embolization and 1 patient with a cerebral infarction who had TEVAR. Four patients (4.3%) who were treated with EVAR with internal iliac artery (IIA) embolization presented with residual buttock claudication 6 months postoperatively, and 3 patients (3.2%) had onset of ischemic enteritis; however, in all 7 patients, the condition resolved without additional intervention. In the 10 patients who had EVAR and a renal artery chimney method, the landing zone (LZ) was ≤10 mm, but neither endoleak nor renal artery occlusion was observed perioperatively or during midterm follow-up. Of the 20 patients who had a 2-debranching TEVAR, including 9 in whom the chimney method was used with the LZ in zone 0, 1 (5%) had a residual endoleak. In 3 patients with TAAA, we used SGs to cover 4 abdominal branches and bypassed the visceral artery; the outcomes were good, with all patients being ambulatory at hospital discharge.

CONCLUSION

Among innovative SGs treatments, the debranching procedure and the chimney method using catheterization and the coil-embolization technique provided good outcomes, as used in addition to surgical procedures. Aortic aneurysm treatment will become increasingly noninvasive with the continuing development of more innovative ways to use the SGs currently available in Japan. (English Translation of Jpn J Vasc Surg 2012; 21: 165-173).

Endovascular treatment of infrarenal abdominal aortic aneurysm with short and angulated neck in high-risk patient

Endovascular treatment of abdominal aortic aneurysms (AAA) is an established alternative to open repair. However lifelong surveillance is still required to monitor endograft function and signal the need for secondary interventions (Hobo and Buth 2006). Aortic morphology, especially related to the proximal neck, often complicates the procedure or increases the risk for late device-related complications (Hobo et al. 2007 and Chisci et al. 2009). The definition of a short and angulated neck is based on length (<15 mm), and angulation (>60°) (Hobo et al. 2007 and Chisci et al. 2009). A challenging neck also offers difficulties during open repairs (OR), necessitating extensive dissection with juxta- or suprarenal aortic cross-clamping. Patients with extensive aneurysmal disease typically have more comorbidities and may not tolerate extensive surgical trauma (Sarac et al. 2002). It is, therefore, unclear whether aneurysms with a challenging proximal neck should be offered EVAR or OR (Cox et al. 2006, Choke et al. 2006, Robbins et al. 2005, Sternbergh III et al. 2002, Dillavou et al. 2003, and Greenberg et al. 2003). In our case the insertion of a thoracic endograft followed by the placement of a bifurcated aortic endograft for the treatment of a very short and severely angulated neck proved to be feasible offering acceptable duration of aneurysm exclusion. This adds up to our armamentarium in the treatment of high-risk patients, and it should be considered in emergency cases when the fenestrated and branched endografts are not available.

Women with abdominal aortic aneurysms have more extensive aortic neck pathology

BACKGROUND

The proportion of women with abdominal aortic aneurysm (AAA) treated with endovascular aortic repair (EVAR) is lower than for open repair (OR). Unfavorable morphologic features for EVAR in women with AAA may explain this disproportion. The objective of this study was to identify morphologic features in AAA patients undergoing elective repair with special emphasis on gender differences.

METHODS

Patients undergoing elective repair from January 1, 2006 to December 31, 2008 at our university's vascular unit were included in this study. Computed tomography (CT) angiograms were analyzed. Morphologic features considered unfavorable for EVAR rather than open repair (OR) included: infrarenal aortic neck <15 mm; angulation >60°; circumferential neck thrombus; neck width >32 mm; iliac arteries <7.5 mm; or presence of bi-iliac aneurysms. Complex aortic neck was defined as a neck length of <15 mm and one or more of the other aortic neck exclusion criteria.

RESULTS

One hundred seventy-two patients, including 140 men and 32 women, were treated during the study period, which included 99 with OR (21 women, 78 men) and 73 with EVAR (11 women, 62 men). Morphologic unsuitability for EVAR was 44% (75 of 172) and was not statistically different between women and men [47% (15 of 32) vs. 43% (60 of 140), P = 0.70]. Aortic neck pathology was the dominating feature for unsuitability for EVAR (69 of 75, 92%), and 85 of 172 patients had an unsuitable aortic neck. This rate was not different between women and men [19 of 32 (59%) vs. 66 of 140 (47%), P = 0.24]. Iliac unsuitability rates were 11% (19 of 172) and were not different between women and men [4 of 32 (12%) vs. 15 of 140 (11%), P = 0.76]. In patients unsuitable for EVAR, the proximal aortic necks showed more extensive aortic neck pathology in women than in men [8 of 15 (53%) vs. 13 of 60 (22%), P = 0.02]. More men had only short neck pathology [22 of 60 (37%) vs. 1 of 15 (7%), P = 0.03].

CONCLUSIONS

Aortic neck pathology is the dominating cause of EVAR exclusion in both genders. A higher proportion of women have more pathologic neck anatomy. Future development of EVAR devices should focus on the complexity of the aortic neck, which will benefit all AAA patients, but especially women.

Systematic review and meta-analysis of the early and late outcomes of open and endovascular repair of abdominal aortic aneurysm

Background

Any possible long-term benefit from endovascular (EVAR) versus open surgical repair for abdominal aortic aneurysm (AAA) remains unproven. Long-term data from the Open Versus Endovascular Repair (OVER) trial add to the debate regarding long-term all-cause and aneurysm-related mortality. The aim of this study was to investigate 30-day and long-term mortality, reintervention, rupture and morbidity after EVAR and open repair for AAA in a systematic review.

Methods

Standard PRISMA guidelines were followed. Random-effects Mantel–Haenszel meta-analysis was performed to evaluate mortality and morbidity outcomes.

Results

The existing published randomized trials, together with information from Medicare and SwedVasc databases, were included in a meta-analysis. This included 25 078 patients undergoing EVAR and 27 142 undergoing open repair for AAA. Patients who had EVAR had a significantly lower 30-day or in-hospital mortality rate (1·3 per cent versus 4·7 per cent for open repair; odds ratio (OR) 0·36, 95 per cent confidence interval 0·21 to 0·61; P &lt; 0·001). By 2-year follow-up there was no difference in all-cause mortality (14·3 versus 15·2 per cent; OR 0·87, 0·72 to 1·06; P = 0·17), which was maintained after at least 4 years of follow-up (34·7 versus 33·8 per cent; OR 1·11, 0·91 to 1·35; P = 0·30). There was no significant difference in aneurysm-related mortality by 2 years or longer follow-up. A significantly higher proportion of patients undergoing EVAR required reintervention (P = 0·003) and suffered aneurysm rupture (P &lt; 0·001).

Conclusion

There is no long-term survival benefit for patients who have EVAR compared with open repair for AAA. There are also significantly higher risks of reintervention and aneurysm rupture after EVAR.

Endovascular aneurysm repair: a perioperative perspective

Endovascular aneurysm repair (EVAR), has surpassed open repair as the technique of choice in many centres in response to several large studies which showed significantly improved 30-day mortality. While several multicentre EVAR trials looked at surgical outcomes, very few have specifically investigated the effect of anaesthetic techniques or perioperative care of these patients. The purpose of this review to is to present some of the current evidence for the different aspects of perioperative management of patients undergoing EVAR. This includes surgical considerations, pre-operative assessment, and choice of anaesthetic technique as well as pharmacological protective strategies.

Suitability of endovascular repair with current stent grafts for abdominal aortic aneurysm in Korean patients

Suitability rate of endovascular aneurysm repair (EVAR) and the anatomic features causing unsuitability have not been well determined in Asian patients who have abdominal aortic aneurysm (AAA). In a single Korean center, a total of 191 patients with abdominal aortic aneurysm (maximal diameter ≥ 4 cm) were identified. Aortoiliac morphologic characteristics in contrast-enhanced computed tomography images were retrospectively reviewed to determine suitability for EVAR with four FDA-approved stent-grafts. AAA was considered ideally suitable for EVAR in 46.6% of patients. The most frequent causes for unsuitability were common iliac artery (CIA) aneurysm (61.8%) and excessive neck angulation (52.9%). Problems such as small and/or short neck and small access were found in minor incidences. If CIA aneurysm is dealt by overstenting with sacrifice of internal iliac artery, suitability rate can increase to 65%. Larger aneurysms were more frequently unsuitable for EVAR and had more chance of having multiple unfavorable features. In conclusion, the overall feasibility rate for EVAR in Korean patients was not different from that in Western patients. However, considering the difference in the major causes of unsuitability, more attention has to be paid to neck angulation and CIA aneurysm to provide EVAR for more Korean patients especially who have large aneurysm.

Long-term outcomes of endovascular aneurysm repair for challenging aortic necks using the Talent endograft

The aim of the present paper is to evaluate the long-term outcomes of endovascular aneurysm repair (EVAR) for challenging aortic necks. Subgroup analyses were performed on 156 patients from the prospective multicenter Talent eLPS (enhanced Low Profile Stent Graft System) trial. Patients with high-risk aortic necks (length < 15 mm or diameter ≥28 mm) were compared with the remaining patients. Patients with high-risk (n = 86) and low-risk necks (n = 70) had similar age and gender distribution. Despite similar prevalences of co-morbidities, the high-risk group had higher Society for Vascular Surgery scores. The high-risk group also had larger maximum aneurysm diameters (56.6 versus 53.0 mm, P < 0.02). There were lower freedoms from major adverse events (MAEs) for the high-risk group at 30 days (84.9 versus 95.7%; P < 0.04) and 365 days (73.4 versus 89.2%; P = 0.02). Effectiveness endpoints at 12 m showed no significant differences. Freedom from all-cause mortality at 30 days (96.5 versus 100%) and aneurysm-related mortality at 365 days (96.0 versus 100%) were similar. At five years, there were no differences in endoleaks or change in aneurysm diameter. All migrations occurred in the high-risk group. The five-year freedom from aneurysm-related mortality for the high- and low-risk groups was 93.2 and 100%, respectively. In conclusion, despite a higher rate of MAEs within the first year and higher migration rates at five years, EVAR in aneurysms with challenging aortic necks can be treated with acceptable long-term results.

The Glasgow Aneurysm Score does not predict mortality after open abdominal aortic aneurysm in the era of endovascular aneurysm repair

OBJECTIVE

Endovascular aneurysm repair (EVAR) has reduced early adverse outcomes from abdominal aortic aneurysm (AAA) repair. Preferential use of EVAR may have altered the profile of patients who undergo open repair. The validity of scoring systems such as the Glasgow Aneurysm Score (GAS), devised when open surgery was the only treatment, required reappraisal.

METHODS

Patients were identified from a database of patients undergoing elective infrarenal aneurysm repair at seven United Kingdom centers, and the GAS was calculated for each patient. Discrimination and calibration were calculated to determine the performance of the model in this setting using the C statistic, tertile analysis, and the χ(2) test. Univariate analysis was performed to determine if a new iteration of the GAS could be produced.

RESULTS

We identified 330 patients who met the inclusion criteria. There were 18 deaths ≤30 days of surgery (5.4%). The average (standard deviation) GAS was 78.6 (8.8) for the survivors and 81.9 (10.4) for nonsurvivors (P = .122). The C statistic was 0.625 (95% confidence interval, 0.481-0.769; P = .75) suggesting a discriminatory ability not much better than chance alone. Despite this, calibration of the model was good. There was no significant difference in the comorbidities of either group, so no recalibration of the GAS could be performed.

CONCLUSION

The GAS did not discriminate between survivors and nonsurvivors after open AAA repair in this cohort. In the era of EVAR, it is possible that the GAS does not predict the outcome of open AAA repair. An alternative explanation is that patients with risk factors for poor outcomes from EVAR, such as adverse AAA morphology, are being selected out for open repair.

Technical modifications for endovascular infrarenal AAA repair for the angulated and dumbbell-shaped neck: the precuff Kilt technique

BACKGROUND

High risk surgical patients with abdominal aortic aneurysms and difficult infrarenal necks continue to be challenged when performing endovascular repair. Although fenestrated and branched endografts may ultimately be the main method of repair for these patients, their current limited availability has prompted the use of alternative endovascular techniques to enhance success of endovascular aortic aneurysm repair in patients with "dumbbell" shaped and angulated necks.

METHODS

A retrospective review of all patients who underwent endovascular abdominal aneurysm repair with a predeployed aortic cuff (Kilt) at University of California, Los Angeles between January 2009 and April 2010 was performed.

RESULTS

Four patients underwent initial Kilt placement before endovascular abdominal aortic aneurysm (AAA) repair. The mean age of these patients was 78.0 + 7.0 years. All were American Society of Anesthesiologists class 3 patients with multiple medical comorbidities. All of them had angulated and dumbbell-shaped necks. Median follow-up period was 11 months (8-18 months). All patients had postoperative computed tomography at 1 and 6 months because of their high-risk neck anatomy. One patient was found to have a large type I endoleak on computed tomography 1 month postoperatively. He required placement of an additional aortic cuff and Palmaz stent, after which the endoleak was found to have resolved. There were no open conversions, aneurysm sac enlargement, or perioperative deaths.

CONCLUSION

Short-term follow-up suggests that the Kilt technique may be useful in certain high-risk patients with traditionally unfavorable anatomy for endovascular abdominal aortic aneurysm repair. It can be performed with minimal patient morbidity, even in high-risk patients. Anatomic features most amenable to this technique include dumbbell-shaped and angulated infrarenal necks.