Hemodynamic Comparison of Stent-Grafts for the Treatment of Aortoiliac Occlusive Disease

Bifurcated Endografts for the Treatment of Aortoiliac Disease a Systematic Review and Individual Patient Data (IPD) Meta-Analysis

BACKGROUND

This review aimed to assess the efficacy and safety of bifurcated endografts in the treatment of aortoiliac disease (AOID).

METHODS

A systematic search on PubMed, Scopus, and Web of Science was performed. The primary endpoint was primary patency, whereas secondary endpoints included reintervention, technical, clinical success, and overall postoperative complications.

RESULTS

Ten studies with a total of 365 patients were included in this review. Most included studies used the AFX unibody endograft, one study the Excluder endograft, and one the Powerlink endograft. The majority of included patients displayed TransAtlantic InterSociety Consensus (TASC) D aortoiliac lesions (56.1% 205/365). The pooled primary patency estimates at 12, 24, and 36 months were 93.93% (95% confidence interval [CI]: 87.7-100), 91.46% (95% CI: 84.6-98.8), and 90.25% (95% CI: 82.6-98.6), respectively. The mean primary patency time was 85.74 months (95% CI: 71.99-86.88). The pooled freedom from reintervention estimates at 12, 24, and 36 months were 91.94% (95% CI: 81.4-100), 91.03% (95% CI: 79.8-100), and 91.03% (95% CI: 79.8-100), respectively. The pooled estimates of major complications (rupture, graft thrombosis, amputation) were 11.12% (95% CI, 0.05%-3.03%), 3.76% (0.32%-9.45%), and 0.38% (0%-2.59%), whereas the pooled estimates for minor complications (hematoma, groin infection, dissection) and overall mortality were 5.27% (95% CI, 1.11%-11.38%), 6.93% (95% CI, 2.94%-12.16%), 2.19% (95% CI, 0.06%-6.14%), and1.57% (95% CI, 0.13-3.97), respectively. Technical and clinical success estimates were 99.92% (95% CI: 98.86%-100%) and 99.47% (95% CI: 94.92%-100%), respectively.

CONCLUSION

The application of bifurcated endografts may present a safe and viable option in the treatment of AOID, with preliminary results indicating promising primary patency outcomes. However, the definitive assessment of their efficacy and safety will be better determined through long-term follow-up studies and high-quality randomized controlled trials, which are essential to substantiate these initial findings.

CLINICAL IMPACT

Bifurcated endograft application may be a safe and viable alternative for high-risk patients with complex AOID TASC C and D lesions with encouraging primary patency outcomes potentially comparable to those of open surgery. Non-negligible postoperative complication rates were also noted. High-quality randomized controlled trials and studies comparing CERAB, kissing stenting, and the use bifurcated endografts for the treatment of AOID is necessary to draw more definite conclusions.

The Long-Term Results of Covered Endovascular Aortic Bifurcation Repair in Complex Aortoiliac Disease: A Two-Year Follow-Up

Background: We aimed to investigate the two-year outcomes of covered endovascular reconstruction (CERAB) of the aortic bifurcation in patients with complex aortoiliac occlusive dis ease. Methods: This study was prospectively initiated, with data retrospectively collected from 40 patients categorized as TASC II B, C, and D based on computed tomography angiography (CTA) findings. All patients underwent the CERAB procedure. We assessed the procedural outcomes, including clinical and symptomatic improvements, as well as patency rates over a two-year follow-up period. Results: A total of 40 patients (33 males and 7 females) with aorto-occlusive disease were treated using the CERAB procedure and included in this observational study. The technical success rate was 100% across all procedures. At 36 months, the overall primary patency, assisted primary patency, and secondary patency rates were 85%, 90%, and 92.5%, respectively. Conclusions: The two-year results of this study suggest that CERAB offers patency rates comparable to those reported in other studies for complex aorto-occlusive bifurcation diseases. The procedure showed favorable patency rates, particularly for more advanced TASC II B, C, and D lesions.

Treatment of common femoral artery steno-occlusive disease: a comprehensive review of anatomical and hemodynamic considerations

Open surgical repair, often in the form of endarterectomy, is still the gold standard for steno-occlusive disease in the common femoral artery, despite the success of lower-risk endovascular alternatives in other peripheral arterial regions. Stenting in the common femoral artery is not widely adopted due to the proximity of the artery to the mobile hip joint, and the perceived risk this has on the stent structure due to kinking. The purpose of this review was to assess how hip movement contributes to the anatomical and biomechanical challenges proposed in the common femoral artery, and how these challenges impact the hemodynamics with both open surgical and endovascular stent treatments. The findings demonstrated that the common femoral artery is a fixed arterial segment which does not bend or twist as previously perceived. However, high degrees of bending and twisting are evident in the vessels directly proximal and distal to the common femoral artery. Mechanical testing suggests that the latest generation braided Nitinol stents could be well-suited to these challenges. Both endarterectomy and stenting provide good hemodynamic results regarding limb perfusion. However, other hemodynamic parameters, such as wall shear stress, may not be optimized with either modality, increasing the risk of chronic restenosis. As a high proportion of common femoral artery disease extends into the adjacent arterial segments, further research is warranted to ascertain the optimum hemodynamic stent configuration, as a lower-risk alternative to open surgery.

Covered endovascular reconstruction of the aortic bifurcation: A systematic review aggregated data and individual participant data meta-analysis

BACKGROUND

We investigated the early and midterm efficacy and safety of covered endovascular reconstruction of the aortic bifurcation (CERAB) in the treatment of aortoiliac disease (AID).

METHODS

A systematic search on PubMed, Scopus, and Web of Science for articles published by August 2023 was performed. The primary end points were primary patency and secondary patency.

RESULTS

Eleven retrospective case series, involving 579 patients, were incorporated in the review with 88.9% of the included lesions being categorized as Trans-Atlantic Inter-Society Consensus (TASC) C or D. The pooled primary patency estimates at 12, 24 and 36 months were 94.4% (95% confidence interval [CI], 89.4-99.7), 84.4% (95% CI, 72.3-98.5) and 83.8% (95% CI, 71.4-98.3) respectively. The mean primary patency time, representing the period during which individuals remained event-free, was 51.9 months (95% CI, 43.6-55.4). The pooled 36 months primary patency for studies with a predominantly claudicant patient population (>75% of patients) was 89.4% (95% CI, 78.5-100.0), compared with 71.5% (95% CI, 45.6-100.0) for studies with a mixed population (50% of patients). The pooled 36 months primary patency for studies with a predominantly TASC D patient population (>82% of patients) was 70.4% (95% CI, 46.4-100.0) compared with 91.0% (95% CI, 79.1-100.0) for studies with a more homogenous cohort. The pooled secondary patency estimates at 12, 24, and 36 months were 98.6% (95% CI, 96.2-100.0), 97% (95% CI, 93.1-100.0), and 97% (95% CI, 93.1-100.0), respectively. The pooled technical success, 30-day mortality and 30-day systemic complications estimates were 95.9% (95% CI, 93.7- 97.4), 1.9% (95% CI, 1.0-3.5), and 6.4% (95% CI, 4.4-9.1), respectively. The pooled intraoperative and postoperative 30-day CERAB-related complications estimates were 7.3% (95% CI, 2.0-23.0) and 4.2% (95% CI, 0.7-21.0), respectively. The pooled major amputation and target lesion reinterventions by the end of follow-up were 1.9% (95% CI, 1.0-3.4) and 13.9% (95% CI, 9.9-19.2), respectively. The pooled access site complication estimate was 11.7% (95% CI, 5.9-21.7).

CONCLUSIONS

Although this review has showcased the safety and feasibility of the CERAB technique in treating AID, it has also highlighted the necessity for a close and prolonged follow-up period extending beyond 1 year. Moreover, the favorable secondary patency estimates predominantly attained via endovascular reinterventions emphasize a potentially advantageous characteristic of the CERAB technique, particularly valuable when addressing late-stage AID disease or anatomically complex lesions.

Combination of BeGraft and Solaris Stent Grafts for the Covered Endovascular Reconstruction of Aortic Bifurcation-BS-CERAB Technique

Background: This study examines the impact of the use of the combination of BeGraft and Solaris stent grafts on the outcomes during the covered endovascular reconstruction of aortic bifurcation (BS-CERAB) technique and extension to the iliac arteries. Methods: Consecutive patients with aortoiliac occlusive disease who underwent endovascular treatment using BS-CERAB between January 2020 and December 2023 were included. Patient demographics, symptoms, lesion characteristics, and procedural and follow-up details were collected and analyzed. Perioperative complications and reinterventions were also identified. Results: A total of 42 patients met the inclusion criteria (32 men, 76.2%, median age 72 years, range 59-85). Indications for treatment were intermittent claudication (42.9%) and critical limb ischemia (57.1%). Procedure success was achieved in all cases. The median patient follow-up time was 14 months (1-36). One patient died at a 10-month follow-up due to lung cancer. The mean pre-operative ABI increased from 0.37 ± 0.19 before intervention to 0.71 ± 1.23 post-operatively at 12 months (p = 0.037). The estimated primary patency rates at 3, 6, and 12 months were 90.5%, 85.7%, and 81.0% and primary assisted patency rates were 90.5%, 90.5%, and 85.7%, respectively. Secondary patency was 95.2% at 3 and 6 months and 90.5% at a 12-month follow-up. Active cancer (p = 0.023, OR 2.12 95%CI 1.14-3.25) was a risk factor for restenosis. Conclusions: This mid-term experience shows that the CERAB technique using the combination of BeGraft and Solaris stents grafts, for the endovascular treatment of severe aortoiliac atherosclerotic disease, may allow an effective reconstruction of the aortic bifurcation and iliac arteries related to high-patency and lower-reintervention rates.

The Technological Advancement to Engineer Next-Generation Stent-Grafts: Design, Material, and Fabrication Techniques

Endovascular treatment of aortic disorders has gained wide acceptance due to reduced physiological burden to the patient compared to open surgery, and ongoing stent-graft evolution has made aortic repair an option for patients with more complex anatomies. To date, commercial stent-grafts are typically developed from established production techniques with simple design structures and limited material ranges. Despite the numerous updated versions of stent-grafts by manufacturers, the reoccurrence of device-related complications raises questions about whether the current manfacturing methods are technically able to eliminate these problems. The technology trend to produce efficient medical devices, including stent-grafts and all similar implants, should eventually change direction to advanced manufacturing techniques. It is expected that through recent advancements, especially the emergence of 4D-printing and smart materials, unprecedented features can be defined for cardiovascular medical implants, like shape change and remote battery-free self-monitoring. 4D-printing technology promises adaptive functionality, a highly desirable feature enabling printed cardiovascular implants to physically transform with time to perform a programmed task. This review provides a thorough assessment of the established technologies for existing stent-grafts and provides technical commentaries on known failure modes. They then discuss the future of advanced technologies and the efforts needed to produce next-generation endovascular implants.

In-vitro and In-silico Haemodynamic Analyses of a Novel Embedded Iliac Branch Device

Background

Iliac branch devices (IBDs) are valid tools for internal iliac artery preservation during endovascular abdominal aortic aneurysm and iliac aneurysm repair. The purpose of this study was to evaluate the effectiveness of a novel IBD with an embedded branch configuration.

Method

A typical iliac artery model was reconstructed, and two models were manufactured using three-dimensional printing technology. The novel IBD was deployed into one iliac artery model by an experienced vascular surgeon. A mock circulation loop (MCL) and a computational fluid dynamics (CFD) simulation were used to investigate the haemodynamic parameters of the iliac models without (Model A) and with (Model B) the IBD. A morphological analysis was conducted using computed tomography angiography and medical endoscopy. The flow distribution rate (FDR) and energy loss (EL) were used to quantify IBD performance.

Results

The FDR of the right internal iliac artery in the MCL of Model A and Model B was 18.88 ± 0.12% and 16.26 ± 0.09%, respectively (P = 0.0013). The FDR of the right internal iliac artery in the CFD simulation of Model A and Model B was 17.52 and 14.49%, respectively. The EL of Model A was greater than Model B in both the MCL and the CFD simulation. Compared with Model A, Model B had a larger region (8.46 vs. 3.64%) with a relative residence time of >20 Pa⁻¹ at peak systole. Meanwhile, the area where the oscillatory flow index was >0.4 was significantly smaller in Model B than in Model A (0.46 vs. 0.043%). The region with an average wall shear stress of >4 Pa was greater in Model B than in Model A (0 vs. 0.22%).

Conclusion

The MCL and CFD simulation showed that the novel IBD had little impact on the FDR and EL of the iliac artery models. However, the IBD might be an effective tool for the treatment of abdominal aortic/iliac aneurysms that extend into branches. Further investigations are warranted to confirm whether this IBD could be useful in the clinic.