The fate of endoleaks after endovascular aneurysm repair and the impact of oral anticoagulation on their persistence

Practice patterns of antiplatelet and anticoagulant therapy after fenestrated/branched endovascular aortic repair

OBJECTIVE

Antiplatelet and/or anticoagulant therapy are commonly prescribed after fenestrated/branched endovascular aortic repair (F/BEVAR). However, the optimal regimen remains unknown. We sought to characterize practice patterns and outcomes of antiplatelet and anticoagulant use in patients who underwent F/BEVAR.

METHODS

Consecutive patients enrolled (2012-2023) as part of the United States Aortic Research Consortium (US-ARC) from 10 independent physician-sponsored investigational device exemption studies were evaluated. The cohort was characterized by medication regimen on discharge from index F/BEVAR: (1) Aspirin alone OR P2Y12 alone (single-antiplatelet therapy [SAPT]); (2) Anticoagulant alone; (3) Aspirin + P2Y12 (dual-antiplatelet therapy [DAPT]); (4) Aspirin + anticoagulant OR P2Y12 + anticoagulant (SAPT + anticoagulant); (5) Aspirin + P2Y12 + anticoagulant (triple therapy [TT]); and (6) No therapy. Kaplan-Meier analysis and Cox proportional hazards modeling were used to compare 1-year outcomes including survival, target artery patency, freedom from bleeding complication, freedom from all reinterventions, and freedom from stent-specific reintervention.

RESULTS

Of the 1525 patients with complete exposure and outcome data, 49.6% were discharged on DAPT, 28.8% on SAPT, 13.6% on SAPT + anticoagulant, 3.2% on TT, 2.6% on anticoagulant alone, and 2.2% on no therapy. Discharge medication regimen was not associated with differences in 1-year survival, bleeding complications, composite reintervention rate, or stent-specific reintervention rate. However, there was a significant difference in 1-year target artery patency. On multivariable analysis comparing with SAPT, DAPT conferred a lower hazard of loss of target artery patency (hazard ratio [HR], 0.48; 95% confidence interval [CI], 0.27-0.84; P = .01). On sub-analyses of renal stents alone or visceral stents alone, DAPT no longer had a significantly lower hazard of loss of target artery patency (renal: HR, 0.66; 95% CI, 0.35-1.27; P = .22; visceral: HR, 0.31; 95% CI, 0.05-1.9; P = .21). Lastly, duration of DAPT therapy (1 month, 6 months, or 1 year) did not significantly affect target artery patency.

CONCLUSIONS

Practice patterns for antiplatelet and anticoagulant regimens after F/BEVAR vary widely across the US-ARC. There were no differences in bleeding complications, survival or reintervention rates among different regimens, but higher branch vessel patency was noted in the DAPT cohort. These data suggest there is a benefit in DAPT therapy. However, the generalizability of this finding is limited by the retrospective nature of this data, and the clinical significance of this finding is unclear, as there is no difference in survival, bleeding, or reintervention rates amongst the different regimens. Hence, an "optimal" regimen, including the duration of such regimen, could not be clearly discerned. This suggests equipoise for a randomized trial, nested within this cohort, to identify the most effective antiplatelet/anticoagulant regimen for the growing number of patients being treated globally with F/BEVAR.

Percutaneous Retrograde Trans-Gluteal Embolization of Type 2 Endoleak Causing Iliac Aneurysm Enlargement after Endovascular Repair: Case Report and Literature Review

Late type II endoleaks (T2ELs) arising from the internal iliac artery (IIA) may present during follow-up after endovascular aortic repair (EVAR) of aortoiliac aneurysm and may warrant embolization if enlargement of the aneurysmal sac is demonstrated. When coverage of the IIA ostium has been made due to extensive iliac disease, access options can be challenging. Different treatment options have been reported over recent years, and a careful selection of the best one must be made based on the characteristics of each case. The present study reports a simple and reproducible sheathless percutaneous superior gluteal artery (SGA) access and provides a discussion based on a review of the existing literature on this topic.

Editor's Choice -- European Society for Vascular Surgery (ESVS) 2024 Clinical Practice Guidelines on the Management of Abdominal Aorto-Iliac Artery Aneurysms

OBJECTIVE

The European Society for Vascular Surgery (ESVS) has developed clinical practice guidelines for the care of patients with aneurysms of the abdominal aorta and iliac arteries in succession to the 2011 and 2019 versions, with the aim of assisting physicians and patients in selecting the best management strategy.

METHODS

The guideline is based on scientific evidence completed with expert opinion on the matter. By summarising and evaluating the best available evidence, recommendations for the evaluation and treatment of patients have been formulated. The recommendations are graded according to a modified European Society of Cardiology grading system, where the strength (class) of each recommendation is graded from I to III and the letters A to C mark the level of evidence.

RESULTS

A total of 160 recommendations have been issued on the following topics: Service standards, including surgical volume and training; Epidemiology, diagnosis, and screening; Management of patients with small abdominal aortic aneurysm (AAA), including surveillance, cardiovascular risk reduction, and indication for repair; Elective AAA repair, including operative risk assessment, open and endovascular repair, and early complications; Ruptured and symptomatic AAA, including peri-operative management, such as permissive hypotension and use of aortic occlusion balloon, open and endovascular repair, and early complications, such as abdominal compartment syndrome and colonic ischaemia; Long term outcome and follow up after AAA repair, including graft infection, endoleaks and follow up routines; Management of complex AAA, including open and endovascular repair; Management of iliac artery aneurysm, including indication for repair and open and endovascular repair; and Miscellaneous aortic problems, including mycotic, inflammatory, and saccular aortic aneurysm. In addition, Shared decision making is being addressed, with supporting information for patients, and Unresolved issues are discussed.

CONCLUSION

The ESVS Clinical Practice Guidelines provide the most comprehensive, up to date, and unbiased advice to clinicians and patients on the management of abdominal aorto-iliac artery aneurysms.

Systematic Review and Meta-Analysis of the Effect of Anticoagulation on Outcomes After Endovascular Aneurysm Repair

PURPOSE

Our objective was to investigate whether patients who receive anticoagulation therapy have different outcomes after endovascular aneurysm repair (EVAR) from those who do not.

MATERIALS AND METHODS

We conducted a systematic review of studies that compared outcomes of EVAR in patients who were on therapeutic anticoagulation vs those who were not. We developed and reported the review in accordance with the PRISMA guidelines with a registered protocol (CRD42022375894). The Ovid interface was used to search Medical Literature Analysis and Retrieval System Online (MEDLINE), Excerpta Medica Database (EMBASE), and Cochrane Central Register of Controlled Trials (CENTRAL) up to November 2022. The quality of studies was assessed with the Newcastle-Ottawa Scale (NOS) (maximum score=9), and the evidence was appraised with the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) framework. The hazard ratio (HR) and 95% confidence interval (CI) was the effect estimate in time-to-event meta-analyses, calculated using the inverse-variance statistical method and random-effects models.

RESULTS

Sixteen studies qualified for inclusion reporting a total of 35 739 individuals. Anticoagulated patients had a statistically significantly higher hazard of death (HR=1.93, 95% CI=1.03-3.63), endoleak (HR=2.13, 95% CI=1.55-2.93), reintervention (HR=1.79, 95% CI=1.27-2.52), and aneurysm sac expansion (HR=2.72, 95% CI=1.57-4.72) than patients not receiving anticoagulation therapy. The median score on the NOS was 7 (range=4-9). The certainty of evidence was very low for mortality and reintervention and low for endoleak and sac expansion.

CONCLUSIONS

Anticoagulation is a poor prognostic factor after standard EVAR and should be considered in decision-making, consent processes, and surveillance strategies.

CLINICAL IMPACT

The number of individuals who take anticoagulation treatment has been rapidly increasing over the recent years. We aimed to investigate the effect of such treatment on outcomes after endovascular aneurysm repair (EVAR). Anticoagulated patients were found to have increased mortality, endoleak, and reintervention rates after EVAR compared to their non-anticoagulated counterparts. Anticoagulation therapy has a prognostic role in EVAR and should be considered in decision making and EVAR surveillance. Anticoagulated patients need to be informed of the higher failure rates of EVAR, and intensified surveillance strategies may need to be implemented in this patient cohort.

Management of Endoleaks After Elective Infrarenal Aortic Endovascular Aneurysm Repair: A Review

Importance

Endovascular aneurysm repair (EVAR) is the dominant treatment strategy for abdominal aortic aneurysms, encompassing 80% of all repairs in the United States. Endoleaks are ubiquitous and affect 30% of patients treated by EVAR, potentially leading to sac enlargement and increased risk of rupture. The care of EVAR patients requires long-term surveillance by a multidisciplinary team. Accordingly, physicians should be familiar with the fundamentals of endoleak management to achieve optimal outcomes, including timely referral for remediation or providing counseling and reassurance when needed.

Observations

PubMed and the Cochrane database were searched for articles published between January 2002 and December 2022 in English, addressing epidemiology, diagnosis, and management of endoleaks after EVAR. Endoleaks can be detected intraoperatively or years later, making lifelong surveillance mandatory. Type I and III have the highest risk of rupture (7.5% at 2 years and 8.9% at 1 year, respectively) and should be treated when identified. Intervention should be considered for other types of endoleak when associated with aneurysm sac growth larger than 5 mm based on current guidelines. Type II endoleaks are the most common, accounting for 50% of all endoleaks. Up to 90% of type II endoleaks resolve spontaneously or are not associated with sac enlargement, requiring only observation. Although the risk of rupture is less than 1%, cases that require reintervention are challenging. Recurrence is common despite endovascular treatment, and rupture can occur without evidence of sac growth. Type IV endoleaks and endotension are uncommon, are typically benign, and primarily should be observed.

Conclusions and Relevance

Endoleak management depends on the type and presence of sac expansion. Type I and III endoleaks require intervention. Type II endoleaks should be observed and treated selectively in patients with significant sac expansion. Since endoleaks can appear any time after EVAR, at least 1 contrast-enhanced computed tomographic angiogram or duplex ultrasound by an experienced laboratory is recommended every 5 years.

Thrombosis in the pathogenesis of abdominal aortic aneurysm

Background

Abdominal aortic aneurysms (AAAs) are a relatively common vascular pathology of the elderly with high morbidity potential. Irreversible degeneration of the aortic wall leads to lethal rupture if left untreated. Nearly all AAAs contain intraluminal thrombus (ILT) to a varying degree, yet the mechanisms explaining how thrombosis is disturbed in AAA are relatively unknown. This review examined the thrombotic complications associated with AAA, the impact of thrombosis on AAA surgical outcomes and AAA pathogenesis, and the use of antithrombotic therapy in the management of this disease.

Methods

A literature search of the PubMed database was conducted using relevant keywords related to thrombosis and AAAs.

Results

Thrombotic complications are relatively infrequent in AAA yet carry significant morbidity risks. The ILT can impact endovascular aneurysm repair by limiting anatomic suitability and influence the risk of endoleaks. Many of the pathologic mechanisms involved in AAA development, including hemodynamics, inflammation, oxidative stress, and aortic wall remodeling, contain pathways that interact with thrombosis. Conversely, the ILT can also be a source of biochemical stress and exacerbate these aneurysmal processes. In animal AAA models, antithrombotic therapies have shown favorable results in preventing and stabilizing AAA. Antiplatelet agents may be beneficial for reducing risks of major adverse cardiovascular events in AAA patients; however, neither antiplatelet nor anticoagulation is currently used solely for the management of AAA.

Conclusions

Thrombosis and ILT may have detrimental effects on AAA growth, rupture risk, and patient outcomes, yet there is limited understanding of the pathologic thrombotic mechanisms in aneurysmal disease at the molecular level. Preventing ILT using platelet and coagulation inhibitors may be a reasonable theoretical target for aneurysm progression and stability; however, the practical benefits of current antithrombotic therapies in AAA are unclear. Further research is needed to demonstrate the extent to which thrombosis impacts AAA pathogenesis and to develop novel pharmacologic strategies for the medical management of this disease.

Realignment of Migrated Celiac Stent Graft After Branched Stent Graft Implantation Through Retrograde Cannulation of the Superior Mesenteric Artery Using a Single Vascular Access

PURPOSE

The purpose of the study was to present an endovascular management of a type IIIc endoleak (EL) in a patient with migration of the bridging stent graft of the celiac trunk (CT) after branched aortic aneurysm repair with retrograde cannulation of the superior mesenteric artery (SMA).

TECHNIQUE

The therapy was applied in a 62-year-old man who underwent a branched EVAR 2 years ago. Meanwhile, the patient was treated due to type Ia EL 6 months ago. The patient suffered in the last days from unclear hemorrhage clinically correlated with weakness. In the computed tomography angiography (CTA), an EL IIIc with a migration of the bridging stent graft from the CT branch was displayed. As vascular access, the left axillar artery was used. Due to the misaligned bridging stent graft, an antegrade cannulation was impossible, so cannulation was performed retrograde through the SMA using pancreaticoduodenal and gastroduodenal arteries. Thereafter, the EL could be repaired with bridging stent grafts. The postinterventional control showed a satisfying reconstruction without EL or embolization.

CONCLUSION

Most of the complications such as type IIIc EL after complex endovascular repair can also be treated endovascularly. This sophisticated treatment requires that necessary materials and experience are available.

Antithrombotic Therapy for Aortic Aneurysms: A Systematic Review and Meta-Analysis

OBJECTIVES

The role of antithrombotic therapy in the management of aortic and peripheral aneurysms is unclear. This systematic review and meta-analysis aimed to assess the impact of antithrombotics on clinical outcomes for aortic and peripheral aneurysms.

METHODS

Medline, Embase, and CENTRAL databases were searched. Randomised controlled trials and observational studies investigating the effect of antithrombotic therapy on clinical outcomes for patients with any aortic or peripheral artery aneurysm were included.

RESULTS

Fifty-nine studies (28 with antiplatelet agents, 12 anticoagulants, two intra-operative heparin, and 16 any antithrombotic agent) involving 122 102 patients were included. Abdominal aortic aneurysm (AAA) growth rate was not significantly associated with the use of antiplatelet therapy (SMD -0.36 mm/year; 95% CI -0.75 - 0.02; p = .060; GRADE certainty: very low). Antithrombotics were associated with increased 30 day mortality for patients with AAAs undergoing intervention (OR 2.30; 95% CI 1.51 - 3.51; p < .001; GRADE certainty: low). Following intervention, antiplatelet therapy was associated with reduced long term all cause mortality (HR 0.84; 95% CI 0.76 - 0.92; p < .001; GRADE certainty: moderate), whilst anticoagulants were associated with increased all cause mortality (HR 1.64; 95% CI 1.14 - 2.37; p = .008; GRADE certainty: very low), endoleak within three years (OR 1.99; 95% CI 1.10 - 3.60; p = .020; I² = 60%; GRADE certainty: very low), and an increased re-intervention rate at one year (OR 3.25; 95% CI 1.82 - 5.82; p < .001; I² = 35%; GRADE certainty: moderate). Five studies examined antithrombotic therapy for popliteal aneurysms. Meta-analysis was not possible due to heterogeneity.

CONCLUSIONS

There was a lack of high quality data examining antithrombotic therapy for patients with aneurysms. Antiplatelet therapy was associated with a reduction in post-intervention all cause mortality for AAA, whilst anticoagulants were associated with an increased risk of all cause mortality, endoleak, and re-intervention. Large, well designed trials are still required to determine the therapeutic benefits of antithrombotic agents in this setting.

Association of Oral Anticoagulation Prescription with Clinical Events in Patients with an Asymptomatic Unrepaired Abdominal Aortic Aneurysm

Background: Most abdominal aortic aneurysms (AAA) have large volumes of intraluminal thrombus which has been implicated in promoting the risk of major adverse events. The aim of this study was to examine the association of therapeutic anticoagulation with AAA-related events and major adverse cardiovascular events (MACE) in patients with an unrepaired AAA. Methods: Patients with an asymptomatic unrepaired AAA were recruited from four sites in Australia. The primary outcome was the combined incidence of AAA repair or AAA rupture-related mortality (AAA-related events). The main secondary outcome was MACE (the combined incidence of myocardial infarction, stroke, or cardiovascular death). The associations of anticoagulation with these outcomes were assessed using Cox proportional hazard analyses (reporting hazard ratio, HR, and 95% confidence intervals, CI) to adjust for other risk factors. Results: A total of 1161 patients were followed for a mean (standard deviation) of 4.9 (4.0) years. Of them, 536 (46.2%) patients had a least one AAA-related event and 319 (27.5%) at least one MACE. In the sample, 98 (8.4%) patients were receiving long-term therapeutic anticoagulation using warfarin (84), apixaban (7), rivaroxaban (6), or dabigatran (1). Prescription of an anticoagulant was associated with a reduced risk of an AAA-related event (adjusted HR 0.61; 95% CI 0.42, 0.90, p = 0.013), but not MACE (HR 1.16; 95% CI 0.78, 1.72, p = 0.476). Conclusions: These findings suggest that AAA-related events but not MACE may be reduced in patients prescribed an anticoagulant medication. Due to the inherent biases of observational studies, a randomized controlled trial is needed to assess whether anticoagulation reduces the risk of AAA-related events.