A systematic review and meta-analysis of proximal aortic neck dilatation after endovascular abdominal aortic aneurysm repair

Remodeling of the Proximal Sealing Zone and Sac Shrinkage After Endovascular Aortic Repair or Fenestrated Endovascular Aortic Repair

OBJECTIVE

Variations in sac shrinkage are noted between endovascular aneurysm repair for abdominal aortic aneurysm and fenestrated endovascular aneurysm repair for short neck abdominal aortic aneurysm. These variations may originate from difference in the geometry and length of proximal sealing, which influences the quality and durability of the seal. This study aimed to explore the disparities in aneurysm exclusion and sac remodeling across these two scenarios.

METHODS

This study involved a retrospective analysis of prospectively collected data from 2014 to 2021. Of 486 endovascular abdominal aortic repair cases, 33 that exclusively used a low permeability ePTFE infrarenal device, strictly adhering to the instructions for use, were selected. Concurrently, 30 cases of fenestrated repair that utilized modified polyester woven fabric devices proximally with consistent use of the aforementioned low-permeability devices infrarenally were examined. The quality of both proximal and distal sealing zones in fenestrated repairs was maintained within the range specified in the ePTFE infrarenal device's instructions for use, ensuring consistent sealing integrity for reliable group comparisons. Key metrics used for analysis were the detection of endoleaks and measurements of sac dimensions. Additional analyses included comparisons of demographic data and postoperative diameter changes in the proximal sealing zone (encompassing 0, 5, 10, 15, and 20 mm below the most proximal sealing stent).

RESULTS

The demographic data and preoperative maximum-minimum diameter of the aneurysms did not differ between the groups. Proximal neck dilatation was similarly observed after both procedures. Immediately after the procedure, the incidence of lumbar arterial type II endoleaks was significantly lower after fenestrated repair than that after endovascular aortic repair (10% vs. 39.4%, p=0.0094). At the final observation, endovascular aortic repair substantially reduced the proximal sealing zone length (-4.73±15.30%), while fenestrated repair maintained the length (21.98±24.34%; p<0.0001). The preservation of the sealing length in fenestrated repairs was attributable to dilation occurring within the sealing range of the proximal device, oversized to accommodate the larger diameters in the more proximal sections of the aorta. The cumulative occurrence of sac shrinkage (>5 mm) following fenestrated repair increased faster than that after endovascular repair (p=0.002).

CONCLUSIONS

Although aortic neck dilatation progressed similarly in both groups, fenestrated repair maintained the sealing length and demonstrated a greater extent of sac shrinkage, even under the challenging circumstances in proximal sealing zone. The superior postoperative results were linked to both the durability of proximal sealing and a lower occurrence of lumbar arterial type II endoleaks, stemming from the effective shuttering of the collateral sources in the proximal lumbar or intercostal arteries.

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.

Implications of aortic neck dilation following thoracic endovascular aortic repair

OBJECTIVE

This article reports on a retrospective observational study designed to evaluate the incidence, etiology, and clinical implications of aortic neck dilation following thoracic endovascular aortic repair (TEVAR) for aneurysms with landing zones II and III.

METHODS

The study included 37 patients who underwent TEVAR and had postoperative computed tomography angiography available within 30 days and at least one computed tomography angiography at 1 year postoperatively. The primary end point was proximal aortic dilation (defined as growth ≥5 mm or ≥10% of the original diameter), and secondary end points included annual growth of the aneurysmal sac, device migration, endoleak, and reintervention with additional neck-related adverse events. The measurements taken during follow-up included the maximum diameter of the aneurysm and aortic diameter at various locations relative to the stent graft.

RESULTS

During follow-up, a significant increase in aortic diameter was observed at the proximal edge of TEVAR. The estimated freedom from 5 mm or 10% proximal aortic neck growth at 1, 2, and 3 years was 81%, 70%, and 65%, respectively. At the proximal edge of TEVAR the type III aortic arch was significantly associated with 5 mm growth during follow-up (P = .047) and this growth (5 mm or 10%) as well as a 10% increase at +20 mm were significantly associated with more aortic-related reinterventions. Moreover, an aortic diameter at the start <36 mm was associated with a greater increase during follow-up (area under curve in receiver operating characteristic >80%; P < .05).

CONCLUSIONS

The study concludes that proximal aortic dilation after TEVAR is a common and progressive phenomenon, and the management strategies for aortic neck dilation, including surveillance, secondary interventions, and open conversion, should be considered carefully to optimize patient outcomes and improve the long-term success of the procedure.

Diminishing Endograft Apposition during Follow-Up Is an Important Indicator of Late Type 1a Endoleak after Endovascular Aneurysm Repair

Late type 1a endoleaks (T1aELs) after endovascular aneurysm repair (EVAR) are hazardous complications which should be avoided. This study investigated the evolution of the shortest apposition length (SAL) post-EVAR and hypothesised that a declining apposition during follow-up may be an indicator of T1aEL development. Patients with a late T1aEL were selected from a consecutive multicentre database. For each T1aEL patient, the preoperative computed tomography angiography (CTA), first postoperative CTA, and pre-endoleak CTA were analysed. T1aEL patients were matched 1:1 to uncomplicated controls, based on endograft type and follow-up duration. Anatomical characteristics and endograft dimensions, including the post-EVAR SAL, were measured. Included were 28 patients with a late T1aEL and 28 matched controls. The SAL decreased from 11.2 mm (5.6-20.6 mm) to 3.9 mm (0.0-11.4 mm) in the T1aEL group (p = 0.006), whereas an increase in SAL was seen in the control group from 21.3 mm (14.1-25.8 mm) to 25.4 mm (19.0-36.2 mm; p = 0.015). On the pre-endoleak CTA, 18 patients (64%) in the T1aEL group had a SAL < 10 mm, and one (4%) patient in the control group had a SAL < 10 mm on the matched CTAs. Moreover, three mechanisms of decreasing sealing zone were identified, which might be used to determine optimal imaging or reintervention strategies. Diminishing SAL < 10 mm is an indicator for T1aEL during follow-up, it is imperative to include apposition analysis during follow-up.

A Scoping Review on the Incidence, Risk Factors, and Outcomes of Proximal Neck Dilatation after Standard and Complex Endovascular Repair for Abdominal Aortic Aneurysms

Background: To define proximal neck dilation (PND) after standard endovascular aneurysm repair (EVAR) and fenestrated EVAR (FEVAR), determining: incidence and risk factors; evidence base that links PND to outcomes of patients; recurring themes or gaps in the literature. Methods: We performed a scoping review and included only full-text English articles with follow-up focusing on PND in patients undergoing EVAR or FEVAR, published between 2000 and 2022. The following PICO question was used to build the search equation: in patients with abdominal-aortic-aneurysm (AAA) (Population) undergoing endovascular repair (Intervention), what are the incidence, risk factors and prognosis of radiologically defined PND (Comparison) on short-term and long-term outcomes (Outcomes)? Results: 15 articles were included after review. Measurement protocols for proximal aortic neck (PAN) varied among individual studies and the definition of PND resulted as heterogeneous. Rate of patients with a PND ranged between 0% and 41%. Large proximal neck (>28 mm) and excessive graft sizing (30%) were predictors for PND. New endografts with low outward radial forces and FEVAR seemed to be protective. Surgical conversion was the definitive option in the case of patients unfit for other endovascular treatments. Conclusions: PND is a frequent finding after EVAR and FEVAR. Excessive graft oversizing and large baseline PAN were predictors of neck enlargement, independently by the type of standard endograft used. FEVAR may be considered protective against complications, together with endografts using low outward radial forces. Lifelong radiological follow-up is mandatory.

Risk factors and adverse events related to supra- and infra-renal aortic dilation at twelve months after endovascular abdominal aortic aneurysm repair

BACKGROUND

Aortic remodeling and its effect on adverse events after endovascular abdominal aneurysm repair (EVAR) remain under investigation. This study aimed to assess aortic diameter alterations after EVAR, related risk factors and consequences to proximal sealing at 12 months.

METHODS

A single-center retrospective analysis of consecutive EVAR patients was undertaken. All patients underwent computed tomography angiography, preoperatively, at 1^st and 12^th month. The infrarenal diameter was measured just below the inferior renal artery, at 7 mm and 15 mm while the suprarenal, just above the superior renal artery (SRA), superior mesenteric artery (SMA) and just below the celiac trunk. Neck-related adverse events included migration and endoleak Ia.

RESULTS

A hundred fifty patients were included. At 1^st month, no significant diameter alteration was recorded at any level. At 12^th month, all infra-renal diameters increased (P<0.001) and diameters at SRA and SMA also augmented (P=0.024 and P=0.007, respectively). Neck diameter >29 mm, supra-renal fixation and oversizing >20% were associated to dilation at 12^th month. Neck adverse events were related to diameter alterations below the inferior renal artery (P=0.017), SRA (P=0.007) and SMA (P=0.05).

CONCLUSIONS

During the 12-month follow-up, aortic dilation may be detected from the supra-renal aorta to the total neck length. Neck dilation may be attributed to large neck diameter, supra-renal fixation, and aggressive oversizing. Neck-related adverse events are more common in patients with aortic dilation at 12 months.