Systemic Review of Persistent Sciatic Artery Management

Safety and Effectiveness of Endovascular Treatment of Complications Associated with Persistent Sciatic Artery: A Qualitative Systematic Review

Clinical question

Is endovascular therapy with stent grafts (SGs) a safe and effective approach to treat complications associated with persistent sciatic artery (PSA)?

Take away point

The current review demonstrated good technical and clinical success rates and a low risk of adverse events with endovascular stent graft management of persistent sciatic artery.

Reference

Koike, Y., Motohashi, K., & Kato, S. (2024). Safety and Effectiveness of Endovascular Treatment of Complications Associated with Persistent Sciatic Artery: A Qualitative Systematic Review. Journal of Vascular and Interventional Radiology.

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Study design

Systemic review, qualitative

Funding Source

None

Setting

Academic

Figure

Summary

Persistent sciatic artery (PSA) is a rare vascular anomaly occurring in 0.025%–0.040% of the population, where the sciatic artery fails to regress during fetal development and continues to supply the lower limb. This anomaly often results in symptoms, with 80% of patients being symptomatic and 48% developing buttock aneurysms due to repetitive trauma and compression from its anatomical position. These aneurysms can lead to complications such as thrombotic occlusion, distal embolization, and even amputation. The primary treatment goals for symptomatic PSA are to prevent distal embolization and aneurysm rupture, typically through bypass surgery combined with embolization. Recently, stent graft (SG) placement has gained attention as an alternative treatment, although concerns about SG durability, potential fracture, and occlusion remain due to the repetitive trauma in the PSA's location. This systematic review aims to assess the safety and effectiveness of endovascular SG placement for treating PSA complications.

This systematic review, registered with the University Medical Information Network, analyzed existing literature on endovascular treatment of persistent sciatic artery (PSA) complications using stent graft (SG) placement. Following PRISMA guidelines, the study included patients with PSA complications such as aneurysms, rupture, or thrombosis, and excluded those without SG placement or without complications at risk of rupture. The literature search, conducted across multiple databases, identified eligible studies based on a predefined PICOS framework. Two authors independently screened and extracted data, resolving discrepancies by consensus. Outcomes assessed included technical and clinical success, patency, SG-related adverse events, reinterventions, amputations, and mortality. Statistical analyses, including Kaplan-Meier curves and Cox regression, were performed to evaluate the associations between SG characteristics and outcomes, with significance set at a p-value of ≤0.05.

The systematic review included 40 records of patients who underwent endovascular treatment with stent grafts (SGs) for persistent sciatic artery (PSA) complications. The study analyzed 31 case reports, 2 case series, and 7 conference proceedings, with a total of 40 patients (median age 67) treated across 41 limbs. Most patients presented with lower limb ischemia or aneurysm. The technical success rate was 100%, but 9.8% of limbs experienced intervention-specific adverse events, including intraprocedural dissection and thrombotic complications. The study found primary and secondary patency rates of 81.5% and 94.5% at 1 year, respectively, with SG occlusions mainly occurring within 2 years. The clinical success rate remained high at 95.7% over two years. SG fracture was rare, and no endoleaks or infections were reported. Univariate analysis showed no significant association between SG characteristics and primary patency rates.

The discussion highlights that endovascular treatment using stent grafts (SGs) for persistent sciatic artery (PSA) complications is effective, showing high technical and clinical success rates with a low risk of adverse events (AEs). The midterm patency and durability of SGs were found to be acceptable, although factors influencing patency remain unclear. The review supports SG placement as a preferable first-line therapy, especially for PSA aneurysms without occlusion, and suggests that endovascular approaches are increasingly favored due to their minimally invasive nature. The discussion also compares the findings with previous reviews and studies, noting similar success rates but emphasizing the need for more consistent follow-up and reporting to better understand long-term outcomes and the potential impact of anatomical factors on patency. The authors recommend SGs as a first-line treatment while acknowledging the limitations of the current data, including potential selection bias and inconsistencies in study methodologies.

Systemic Review of Renal Artery Aneurysm Management

A Qualitative Systematic Review of Endovascular Management of Renal Artery Aneurysms

Clinical question

How does endovascular management of renal artery aneurysms fare in a qualitative systemic review of the literature?

Take away point

Systematic review of 454 renal artery aneurysms management demonstrated that endovascular approaches were associated with high technical success (96%), a low rate of moderate-to-severe adverse events (6.7%; the most common being renal infarction, but only 16% were clinically evident), and no periprocedural mortality (0%).

Reference

Sheahan, K.P., Alam, I., Pehlivan, T., Pasqui, E., Briody, H., Kok, H.K., Asadi, H. and Lee, M.J., 2024. A systematic review of endovascular management of renal artery aneurysms. Journal of Vascular and Interventional Radiology.

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Study design

Systemic review

Funding Source

None

Setting

Academic

Figure

Figure. A Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) flowchart showing the search, review, and selection process. RAA = renal artery aneurysm.

Summary

Renal artery aneurysms (RAAs) are increasingly detected incidentally, with rupture rates of 3%–5% and associated mortality, especially in nonpregnant patients. Key risk factors include aneurysm size over 20 mm, progressive enlargement, and hypertension, with treatment recommended for aneurysms larger than 2-3 cm, progressive growth, or in pregnant women due to the high mortality risk during peripartum rupture (peripartum rupture is associated with mortality rates of up to 100% for the baby and 80% for the mother). Although there is limited prospective data comparing operative or endovascular repair with surveillance, endovascular techniques have emerged as the preferred treatment for most RAAs due to advancements in technology, quicker recovery times, and high success rates. This study reviews the evidence on endovascular treatment of RAAs, focusing on technical success, adverse events, treatment options, and intermediate to long-term outcomes to guide optimal management strategies.

This systematic review, registered with the PROSPERO database and conducted following Cochrane and PRISMA guidelines, aimed to evaluate the safety and effectiveness of endovascular treatment for renal artery aneurysms (RAAs). A comprehensive search of multiple databases identified studies published between 2000 and 2022, focusing on those with at least five patients undergoing endovascular treatment. Two authors independently selected and reviewed studies, with disagreements resolved through consensus. The review assessed RAA-related mortality, rupture rates, and secondary outcomes such as renal infarction and reintervention. Data analysis included descriptive statistics on outcomes, and a quality and risk-of-bias assessment was performed using the Risk of Bias in Nonrandomized Studies of Interventions tool. The study sought to provide clarity on optimal RAA management by reviewing technical success, adverse events, and long-term outcomes of endovascular techniques.

The systematic review included 26 single-center, retrospective observational studies published between 2007 and 2022, encompassing 13 cross-sectional studies, 6 cohort studies, and 7 case series. A total of 371 patients were reviewed, with a mean age of 53.8 years and a female predominance of 62%. Fibromuscular dysplasia was noted in 26% of cases, though its type was not specified. The majority (53%) of renal artery aneurysms (RAAs) were asymptomatic and most commonly located at the hilar bifurcation.

Endovascular management of renal artery aneurysms (RAAs) employed various techniques, each contributing to the high technical success rate of 96.69% observed across studies. The primary technique used was coil embolization, which accounted for 42% (n=191) of the procedures. This method involves the insertion of coils into the aneurysm to promote clot formation and vessel occlusion. Stent-assisted coiling was the next most common approach, used in 21.5% (n=98) of cases, where a stent is placed to maintain vessel patency while coils are deployed to occlude the aneurysm. Other techniques included the use of flow-diverting stents, liquid embolics, and covered stents, each chosen based on the aneurysm's characteristics and location. Despite the variety of methods, the overall complication rate was 22.9%, with severe adverse events occurring in 6.7% of cases. Mild complications, such as minor renal infarctions and postembolization syndrome (PES), were relatively common, while severe complications, including significant renal impairment, were rare. The need for reintervention was low, at 3%, typically due to issues like incomplete occlusion or reperfusion of the aneurysm sac.

Endovascular treatment of renal artery aneurysms (RAAs) is favored due to its reduced invasiveness, offering better outcomes compared to open surgery, especially for elderly patients and those with comorbidities. Techniques like coil embolization, stent grafts, and flow-diverting stents are employed based on aneurysm characteristics, with coil embolization being the most common but also associated with the highest number of mild adverse events. The study highlights the need for careful patient selection, particularly when dealing with complex aneurysms or when considering younger patients for stent grafts. Despite the technical success and low severe adverse event rate (6.7%), the risk of delayed aneurysm reperfusion necessitates ongoing surveillance. The discussion underscores the challenges of comparing different endovascular techniques and the need for standardization in adverse event reporting, antiplatelet therapy, and follow-up protocols to further refine treatment approaches.

Safety and efficacy of Computer Assisted Vacuum Thrombectomy

Clinical, Functional, and Quality of Life Outcomes after Computer Assisted Vacuum Thrombectomy for Pulmonary Embolism Interim Analysis of the STRIKE-PE Study

Clinical question

How safe and effective is Computer Assisted Vacuum Thrombectomy for treating Pulmonary Embolism?

Take away point

There is a significant reduction in pulmonary artery pressure and right ventricle to left ventricle ratios as well as improvement in 90-day functional and quality of life outcomes associated with the use of Computer Assisted Vacuum Thrombectomy.

Reference

Moriarty JM, Dohad SY, Schiro BJ, et al. Clinical, Functional, and Quality of Life Outcomes after Computer Assisted Vacuum Thrombectomy for Pulmonary Embolism: Interim Analysis of the STRIKE-PE Study. Journal of vascular and interventional radiology. Published online May 1, 2024. doi: https://doi.org/10.1016/j.jvir.2024.04.028

‌Study design

Prospective observational cohort study.

Funding Source

Industry sponsored; Penumbra.

Setting

International multi-institutional study across the USA and Europe.

Figure

Summary

The annual incidence of pulmonary embolism (PE) is increasing and there is significant associated morbidity for surviving patients in terms of decreased overall quality of life. Endovascular treatment strategies have promising clinical outcomes. But longer-term patient-reported outcomes and PE associated morbidity are lacking. The STRIKE-PE study is a muti-institutional prospective study evaluating the long-term safety and treatment outcomes after computer aided vacuum thrombectomy of PE. This article is the first interim analysis of the STRIKE-PE study and evaluates the safety and effectiveness of computer assisted vacuum thrombectomy (CAVT) for the first 150 patients through 90-day follow-up.

All 150 patients were treated with the Indigo Aspiration Mechanical thrombectomy system in combination with the automated computer assisted algorithm. The right ventricle to left ventricle (RV to LV) ratio and incidence of major adverse events within 48 hours were the primary endpoints of the study.
· The RV to LV ratio was assessed on computed tomography pulmonary angiograms.
· Major adverse events included device-related death, major bleeding, device associated pulmonary vascular or cardiac injury and clinical deterioration including prolonged end-organ hypoperfusion or cardiopulmonary resuscitation.

Quality of life and functional improvements were utilized as secondary endpoints.
· Functional outcomes were assessed using the Borg scale of dyspnea at rest and the New York Heart Association classification of heart failure.
· Quality of Life was assessed using the EQ-5D-5L questionnaire, the EQ visual analog scale and the Pulmonary Embolism Quality of Life questionnaire.

Overall, the authors found that the use of computer assisted vacuum thrombectomy was associated with a 16.3% reduction in pulmonary artery pressures, a 25.7% reduction in the RV to LV ratio. Four (2.7%) of the patients experienced major adverse events within 48 hours. Patients exhibited statistically significant improvements in their quality of life at 90 days after the procedure.

The authors discussed that their observed 25.7% reduction in RV to LV ratio was similar to other prospective single-arm clinical studies assessing endovascular approaches for the treatment of PE. The total device time in this study, 33.5 minutes, was lower, although the total procedure time was comparable to other aspiration thrombectomy studies. The reported major adverse events seen during the current study included major bleeding and device related clinical deterioration, which were similar to prior studies. Due to a relative paucity of data in literature, the authors were unable to compare the observed functional and quality of life improvements. However, the authors did emphasize that the FDA and the European Agency for the Evaluation of Medicinal Products both recommend monitoring patient-reported outcomes as effective endpoints in similar clinical trials. The limitations of the study included a lack of comparison with other procedural interventions and medical management with anticoagulation. In addition, as the functional and quality of life questionnaires are not specific to pulmonary embolism, concurrent treatment of other comorbid conditions may have confounded the data. Finally, there was potential bias as the RV to LV ratio was reported by the treating physicians and not through standardized core laboratory examination.

In conclusion, the authors reported that treating PE with computer assisted vacuum thrombectomy resulted in improved RV to LV ratios and pulmonary arterial pressures with an acceptable safety profile as well as improved functional and quality of life outcomes at 90-day follow-up.

Commentary

The authors reported the interim results from ongoing STRIKE-PE trial. The study was tailored to prospectively evaluate the safety and long-term outcomes of computer assisted vacuum thrombectomy with a large patient population from multiple institutions. The reported initial results demonstrated decreased right heart strain and improved 90-day functional and quality of life outcomes. There remained a paucity of data in literature examining the long-term patient outcomes after treatment of PE, which is of paramount importance for informing morbidity of surviving patients after PE treatment. The recognition of this importance by the FDA, and the inclusion of functional outcome assessment in this and other similar clinical trials represented progress in the field where long-term morbidity is regarded as important as the immediate clinical success. A potential area of improvement involves the development of PE-focused functional and quality of life measures, which can allow PE-specific assessment rather than a generalized morbidity questionnaire.

Approximately 3% of patients in this study experienced major adverse events associated with computer assisted vacuum thrombectomy, suggesting a strong safety profile. Also, the mitigation of blood loss can decrease the need for blood transfusion. Furthermore, the median ICU stay was 1 day and 38% of the patients did not require postprocedural ICU level of care. Finally, the total device time associated with computer assisted vacuum thrombectomy was less than similar mechanical thrombectomy devices though the total procedure time was comparable. This data can be leveraged by Interventional Radiology departments to acquire the necessary PE treatment equipment.

The STRIKE-PE trial is still ongoing, and it will be interesting to see the safety and immediate clinical outcomes of the entire patient population of 600 patients, as well as longer-term morbidity and functional outcomes. Future trials can also focus on comparing the efficacy of computer assisted vacuum thrombectomy with other methods of treatment. Overall, the initial interim results from the STRIKE-PE trial bolsters the use of computer assisted vacuum thrombectomy for PE with promising safety and effectiveness profile.

Post Author
Aniket Pandya, MD
ESIR Resident, PGY-4
University of Massachusetts Chan Medical School