Contemporary Treatment of Popliteal Artery Aneurysms in 14 Countries: A Vascunet Report

Resolving the Challenges of an Enormous Popliteal Artery Aneurysm Rupture

Popliteal artery aneurysm rupture represents a diagnostic and therapeutic challenge. In this case report, we report the open surgical therapy of an enormous ruptured popliteal artery aneurysm (rPAA) (13 cm), emphasizing key points in diagnosis and treatment decision-making. The symptomatology of rPAAs is often misleading, with nonspecific signs such as edema and pain, which can lead to delayed diagnosis. Early recognition and appropriate treatment are critical to avoid complications such as acute limb ischemia and amputation.

Chronobiological perspectives and meteorological associations in symptomatic popliteal artery aneurysms

The potential influence of circadian rhythm, seasonal variations, and alterations in meteorological parameters has been studied across various vascular events. However, there is a lack of evidence on the potential chronobiological impacts on thromboembolic events related to the most common peripheral aneurysm, the popliteal artery aneurysm (PAA). Data was obtained from a German PAA registry and the German Meteorological Service (Deutscher Wetterdienst). In this observational cohort study seasonality and chronobiology as well as associations with meteorological parameters of symptomatic PAA were investigated. In a multivariate logistic regression analysis, it was further analyzed whether meteorological parameters could distinguish asymptomatic from symptomatic patients in the registry. Of 1200 registered PAA, n = 142 PAA presented with acute limb ischemia between February 2011 and September 2022. More symptomatic patients (57.0%) presented to the hospital between January and June than in the second half of the year with a nadir in the fall season. Symptom onset was predominantly in the morning hours (39.5%). Atmospheric pressure and humidity values from the index dates diverged from a normal distribution showing a bimodal ("double-peak") configuration. Most patients developed symptoms after a reduction in temperatures compared to 1 or 2 d prior to the index date. However, we found evidence for an interaction between age and temperature difference, where the effects of a decreasing temperature fade with increasing age. Facing the complexity of individual-environment interactions, further investigations are needed to determine whether meteorological parameters are true risk modifiers or surrogates for seasonal differences and altered behaviors.

Deciphering Popliteal Artery Aneurysm Patient Diversity: Insights From a Cluster Analysis of the POPART Registry

BACKGROUND

Popliteal artery aneurysms (PAAs) are the most common peripheral aneurysm. However, due to its rarity, the cumulative body of evidence regarding patient patterns, treatment strategies, and perioperative outcomes is limited. This analysis aims to investigate distinct phenotypical patient profiles and associated treatment and outcomes in patients with a PAA by performing an unsupervised clustering analysis of the POPART (Practice of Popliteal Artery Aneurysm Repair and Therapy) registry.

METHODS AND RESULTS

A cluster analysis (using k-means clustering) was performed on data obtained from the multicenter POPART registry (42 centers from Germany and Luxembourg). Sensitivity analyses were conducted to explore validity and stability. Using 2 clusters, patients were primarily separated by the absence or presence of clinical symptoms. Within the cluster of symptomatic patients, the main difference between patients with acute limb ischemia presentation and nonemergency symptomatic patients was PAA diameter. When using 6 clusters, patients were primarily grouped by comorbidities, with patients with acute limb ischemia forming a separate cluster. Despite markedly different risk profiles, perioperative complication rates appeared to be positively associated with the proportion of emergency patients. However, clusters with a higher proportion of patients having any symptoms before treatment experienced a lower rate of perioperative complications.

CONCLUSIONS

The conducted analyses revealed both an insight to the public health reality of PAA care as well as patients with PAA at elevated risk for adverse outcomes. This analysis suggests that the preoperative clinic is a far more crucial adjunct to the patient's preoperative risk assessment than the patient's epidemiological profile by itself.

[Vascular Registry is a tool for quality improvement in vascular medicine]

A 2002 óta működő Érsebészeti Regiszter kezdetben verőérműtétek adatainak gyűjtéséből és a beavatkozások eredményeinek elemzéséből állt. Nagy előrelépést jelentett 2006-ban az Európai Érsebész Társaság VASCUNET Munkacsoportjához történő csatlakozás, mely szervezet azóta globális nemzetközi tudományos együttműködéssé fejlődött. A hazai regiszter adatainak felhasználásával az elmúlt 15 évben számos nagy nemzetközi tanulmányt folytattunk le, és ezek alapján több mint 30 publikáció jelent meg, melyekben aktív szerepet vállaltak a Magyar Angiológiai és Érsebészeti Társaság Regiszter Bizottságának tagjai is. Az egyes országok vascularis ellátásának jellemzőit és eredményeit összehasonlító tanulmányok különösen hasznos következtetések levonását tették lehetővé, ami hozzájárulhat vascularis ellátórendszerünk fejlődéséhez. Az újonnan létrehozott Nemzeti Vaszkuláris Regiszter további jelentősége, hogy a tudományos elemző tevékenység mellett fontos szerepet játszhat az érgyógyászati minőségfejlesztésben is. Orv Hetil. 2024; 165(24–25): 950–954.

Residual Popliteal Aneurysm Perfusion Leading to Embolic Complications: A Case Report

Introduction

Surgical management of popliteal artery aneurysms has been described for half a century. Long term development of the excluded aneurysm sac in the popliteal segment however remains widely unknown, with only a few small series describing outcomes. Residual aneurysm perfusion has the potential to lead to serious complications.

Report

A 63 year old man presents with skin and soft tissue necrosis of the right calf two years after proximal and distal aneurysm ligation and great saphenous vein bypass for a popliteal artery aneurysm. Computed tomography and magnetic resonance angiography show perfusion of the excluded aneurysm as well as extensive necrosis of the gastrocnemius muscle. Direct angiography of the aneurysm demonstrated retrograde aneurysm perfusion due to insufficient distal ligation with recurrent micro-embolisation to the calf via geniculate arteries. Coiling of the geniculate arteries was performed, plugging the connection to the tibiofibular trunk and embolisation of the aneurysm sac. After the intervention, no flow was seen in the aneurysm sac and the patient made full recovery.

Discussion

Residual aneurysm sac perfusion can lead to complications long after successful aneurysm exclusion. Follow-up after surgery of popliteal aneurysms should include observation of the excluded aneurysm sac with control of residual blood flow. For persistent sac perfusion, aneurysm enlargement or symptoms, further treatment should be considered. Surgical aspects such as complete transection of the artery after aneurysm ligation or end to end anastomosis of the bypass may be considered, to prevent such complications.

Sex disparities in popliteal artery aneurysms

OBJECTIVE

Only 5% of patients with popliteal artery aneurysms (PAAs) are female. Evidence on PAA treatment and outcomes in women is therefore scarce. The POPART Registry provides one of Europe's largest data collections regarding PAA treatment. Data on clinical presentation, aneurysm morphology, and perioperative outcomes after open surgical PAA repair in women will be presented.

METHODS

POPART is a multicenter, noninterventional registry for open and endovascular PAA repair, with 42 participating centers in Germany and Luxembourg. All patients aged >18 years who have been treated for PAA since 2010 are eligible for study inclusion. Data collection is based on an online electronic case report form.

RESULTS

Of the 1236 PAAs, 58 (4.8%) were in women. There were no significant differences in age or cardiopulmonary comorbidities. However, female patients had a lower prevalence of contralateral PAAs and abdominal aortic aneurysms (P < .05). PAAs in women were more likely to be symptomatic before surgery (65.5% vs 49.4%; P = .017), with 19% of women presenting with acute limb ischemia (vs 11%; P = .067). Women had smaller aneurysm diameters than men (22.5 mm vs 27 mm; P = .004) and became symptomatic at smaller diameters (20 mm vs 26 mm; P = .002). Only 8.6% of women and 11.6% of men underwent endovascular aneurysm repair (P > .05); therefore, the perioperative outcome analysis focused on open surgical repair. In total, 23.5% of women and 16.9% of men developed perioperative complications (P > .05). There were no differences in major cardiovascular events (P > .05), but women showed a higher incidence of impaired wound healing (15.7% vs 7.2%; P = .05) and major amputation (5.9% vs 1.1%; P = .027). Female sex was significantly associated with the need for nonvascular reinterventions within 30 days after surgery (odds ratio: 2.48, 95% confidence interval: 1.26-4.88), whereas no significant differences in the odds for vascular reinterventions were observed (odds ratio: 1.98, 95% confidence interval: 0.68-5.77). In the multiple logistic regression model, female sex, symptomatic PAAs, poor quality of outflow vessels, and graft material other than vein graft were independently associated with perioperative reinterventions.

CONCLUSIONS

Women have smaller PAAs, are more likely to be symptomatic before treatment, and are more often affected by nonvascular reinterventions in the perioperative course. As our understanding of aneurysmatic diseases in women continues to expand, sex-specific treatment strategies and screening options for women in well-selected cohorts with modified screening protocols should be continuously re-evaluated.

Emergency treatment of popliteal aneurysms: Single center experience and systematic review and meta-analysis of endovascular versus open repair

BACKGROUND

Popliteal artery aneurysms (PAA) were traditionally treated by open repair (OR). Endovascular repair (ER) has become a new treatment strategy. The aim of this systemic review and meta-analysis was to evaluate and compare the current outcomes of OR and ER in the emergency treatment of PAA.

METHODS

A systematic literature search of the PubMed/Medline database was carried out. Outcomes were 30-day mortality, morbidity, major amputation rate (30 days), major amputation rate (1 year), 1-year primary patency rate, 1-year secondary patency rate and 1-year survival. Additionally, we included clinical data of patients with popliteal aneurysms treated between 2009 and 2021 at the Martin-Luther University Halle-Wittenberg.

RESULTS

We identified two cohort studies from 2014 and 2015 with a total of 199 patients that underwent emergent surgery (39 ER and 160 OR). We also included 26 patients from our institution. For emergency treatment, 30-day major amputation rates (18% vs 3%, Odds Ratio 5.82, 95% CI [1.75; 19.30], p = .004), 30-day mortality rates (10% vs 1%, Odds Ratio 5.57, 95% CI [1.01; 30.58], p = .05), 1-year major amputation rates (15% vs 6% Odds Ratio 3.61, 95% CI [1.18; 11.09], p = .02), 1-year loss of primary patency (54% vs 23%, Odds Ratio 3.19, 95% CI [0.91; 11.20], p = .07), and 1-year loss of secondary patency (44% vs 12%, Odds Ratio 6.91, 95% CI [3.01; 15.83], p < .05) were higher in the ER group when compared to the OR group.

CONCLUSION

Endovascular repair represents an alternative approach for the emergency treatment of PAA. Limited evidence from the available non-randomized studies shows unfavorable outcomes for patients undergoing ER. However, the results are prone to selection bias, and only randomized trials comparing ER to OR might reveal whether a subgroup of patients would benefit from ER as primary treatment of PAA in an emergency setting.

Popliteal artery aneurysm ultrasound criteria for reporting characteristics

INTRODUCTION

Duplex ultrasound (DUS) is the modality of choice for surveillance of popliteal artery aneurysms (PAAs). However, noninvasive vascular laboratories have no standard guidelines for reporting results. This study assessed reports of PAA DUS for inclusion of information pertinent to operative decision-making and timing of surveillance.

METHODS

This study was a retrospective review of a multi-institutional repository that was queried for all patients with a PAA from 2008 to 2022 and confirmed via manual chart review. DUS reports were abstracted and images were individually annotated for features of interest including dimensions, flow abnormalities, and percent thrombus burden.

RESULTS

A total of 166 PAAs in 130 patients had at least one DUS available for viewing. Postoperative surveillance of PAAs was performed at several intervals: the first at 30 months (IQR 3.7-113, n = 44), the second at 64 months (IQR 20-172, n = 31), and the third at 152 months (IQR 46-217, n = 16) after the operation. The largest diameter of operative PAAs (median 27.5 mm, IQR 21.8-38.0) was significantly greater than nonoperative PAAs (median 20.9 mm, IQR 16.7-27.3); p < 0.01. Fewer than 33 (21%) reports commented on patency of distal runoff. We calculated an average percent thrombus of 60% (IQR 19-81) in nonoperative PAAs, which is significantly smaller than 75% (IQR 58-89) in operative PAAs; p < 0.01.

CONCLUSION

In this multi-institutional retrospective study, PAAs are often not followed at intervals recommended by the Society for Vascular Surgery guidelines and do not include all measurements necessary for clinical decision-making in the multi-institutional repository studied. There should be standardization of PAA DUS protocols performed by all noninvasive vascular laboratories to ensure completeness of PAA DUS images and inclusion of characteristics pertinent to clinical decision-making in radiology reports.

Early and long-term results of surgical treatment of popliteal artery aneurysms using a heparin-bonded expanded polytetrafluorethilene graft

BACKGROUND

The aim of the present study was to assess early and long-term results of open surgical interventions for popliteal artery aneurysms (PAAs) with the use of heparin-bonded expanded polytetrafluorethylene (HePTFE) in a single center, retrospective, non-comparative cohort study.

METHODS

A retrospective analysis of a prospectively maintained dataset, including 207 open interventions for PAAs between 2002 and 2022, was performed and 170 procedures carried on with the use of a HePTFE graft were found. Perioperative results were analyzed in terms of mortality, graft thrombosis and amputation rates. Follow-up results were analyzed in terms of survival, primary and secondary patency, freedom from amputation, freedom from reintervention with life-table analysis and Kaplan Meier curves. Follow-up results were considered as primary outcomes, whereas perioperative results were considered as secondary outcomes.

RESULTS

In 82 interventions (48%) the PAA was asymptomatic. In 140 cases a medial approach was used, while in 30 cases a posterior approach was preferred. The level of the distal anastomosis was the p3 tract of the popliteal artery in 89% of the cases. One perioperative death occurred; early thromboses occurred in eight cases and the overall perioperative amputation rate was 2.8%. The median duration of follow-up was 48 months (range 1-251). Estimated survival rate at 10 years was 55% (standard error, SE, 0.065). The 10-year rates of primary and secondary patency and freedom from amputation were 40.8% (SE 0.06), 47.6% (SE 0.065) and 93.4% (SE 0.04), respectively. The estimated freedom from reintervention rate at 10 years was 57% (SE 0.05).

CONCLUSIONS

The results of this large monocentric experience showed that open surgical repair of PAAs with HePTFE is a safe procedure, with low rates of perioperative complications, and excellent results in the long-term setting.

Apolipoprotein E (ApoE) Rescues the Contractile Smooth Muscle Cell Phenotype in Popliteal Artery Aneurysm Disease

Popliteal artery aneurysm (PAA) is the most frequent peripheral aneurysm, primarily seen in male smokers with a prevalence below 1%. This exploratory study aims to shed light on cellular mechanisms involved in PAA progression. Sixteen human PAA and eight non-aneurysmatic popliteal artery samples, partially from the same patients, were analyzed by immunohistochemistry, fluorescence imaging, Affymetrix mRNA expression profiling, qPCR and OLink proteomics, and compared to atherosclerotic (n = 6) and abdominal aortic aneurysm (AAA) tissue (n = 19). Additionally, primary cell culture of PAA-derived vascular smooth muscle cells (VSMC) was established for modulation and growth analysis. Compared to non-aneurysmatic popliteal arteries, VSMCs lose the contractile phenotype and the cell proliferation rate increases significantly in PAA. Array analysis identified APOE higher expressed in PAA samples, co-localizing with VSMCs. APOE stimulation of primary human PAA VSMCs significantly reduced cell proliferation. Accordingly, contractile VSMC markers were significantly upregulated. A single case of osseous mechanically induced PAA with a non-diseased VSMC profile emphasizes these findings. Carefully concluded, PAA pathogenesis shows similar features to AAA, yet the mechanisms involved might differ. APOE is specifically higher expressed in PAA tissue and could be involved in VSMC phenotype rescue.

Endoleak following endovascular repair of popliteal artery aneurysm: clinical outcome and contrast-enhanced ultrasound detection

BACKGROUND

Continued blood flow in the aneurysm sac after repair, also known as endoleak, can occur after both open and endovascular popliteal aneurysm repair (EPAR) with risk for aneurysm sac enlargement. Primary aims were to investigate aneurysm sac growth and the presence and classification of endoleak after EPAR using contrast-enhanced ultrasound (CEUS).

METHODS

Cross-sectional study of patients receiving EPAR with expanded polytetrafluorethylene (ePTFE) covered stent-grafts between 1^st of January 2009 and 1^st of February 2019 at a tertiary referral endovascular center. Patients were re-invited in 2021 and 31 legs were examined for endoleak using CEUS. Endoleaks were classified by a core-lab consisting of three CEUS-experienced physicians.

RESULTS

Median follow-up was 57 months (range 33-143 months). Endoleak was detected in 16 PAA, and categorized as type I (N.=3), type II (N.=10), type III (N.=1) or indeterminate (N.=2). Median maximal PAA diameter was 24 mm (range 15-55 mm) at the time of EPAR compared to 17 mm (range 6-43 mm) at follow-up (P<.001). Maximal aneurysm sac diameter was smaller at follow-up than at the index procedure in both PAAs with and without endoleak on CEUS (P=0.005 vs. P<0.001, respectively). There was no difference in PAA sac shrinkage at follow-up between patients with or without endoleak (P=0.28). Freedom from aneurysm sac growth was 97%.

CONCLUSIONS

CEUS was sensitive in endoleak detection after EPAR. Shrinkage of the PAA sac was found in both patients with and without endoleaks. CEUS appears useful for targeted examinations rather than routine surveillance after EPAR.

Angiosarcoma after popliteal aneurysm exclusion surgery. A systematic review

OBJECTIVE

Expansion after popliteal artery aneurysm exclusion with bypass is a common phenomenon. Popliteal angiosarcoma is seldom reported in literature and in most cases after popliteal artery aneurysm surgery. This paper aims to present the case of a popliteal angiosarcoma, initially diagnosed as late aneurysmal growth after exclusion surgery, to conduct a systematic review of popliteal angiosarcoma and assess any association between angiosarcoma and previous popliteal aneurysm surgery.

METHODS

We performed a secondary popliteal aneurysmorraphy through posterior approach for symptomatic aneurysm expansion in a 79-year-old woman, 9 years after medial femoropopliteal venous bypass and aneurysm exclusion. The postoperative course was complicated by recurrent hematomas and wound spillages requiring multiple revisions. Pathological analysis identified an angiosarcoma. Staging revealed bone invasion and pulmonary metastasis. Despite transfemoral amputation and adjuvant chemotherapy the patient died eight months later. We performed a systematic review through MEDLINE on 'primary' and 'secondary' (with previous vascular surgery) angiosarcoma in popliteal artery aneurysm. Research was done using the terms '(hem)angiosarcoma', 'aneurysm', 'popliteal aneurysm or artery', 'femoral aneurysm or artery'. Other soft tissue sarcoma or non-popliteal locations were excluded.

RESULTS

Including this case, only 13 angiosarcomas in popliteal aneurysms are currently described. Two were reported without previous surgery considered a primary angiosarcoma and 11 after popliteal artery aneurysm surgery (secondary angiosarcoma). Patient age ranges from 8 months to 83 years with a male predominance (10/3). Nine of the 11 patients with secondary angiosarcoma were initially diagnosed as popliteal aneurysm expansion after previous bypass surgery, the two other secondary cases presented respectively with pain and inflammatory syndrome without expansion. All prior surgical exclusion were carried out by a medial approach. Interval with the index operation ranges from 3 months to 15 years. Death was reported in 8 of the 13 cases within the first year of diagnosis.

CONCLUSION

Although seldom reported, popliteal angiosarcomas are mainly described after popliteal artery aneurysm exclusion surgery, raising suspicion on a potential association, yet causality cannot be demonstrated. Angiosarcoma should be included in the differential diagnosis of popliteal aneurysm growth or unexpected outcome after exclusion bypass surgery. Systematic imaging and pathological studies should be undertaken to allow early diagnosis and treatment. Routine use of a posterior approach, with aneurysm resection, when feasible as initial popliteal artery aneurysm treatment, might reduce the risk of late sarcomatous transformation.

Early and mid-term outcomes of open popliteal artery aneurysm repair with prosthetic grafts

OBJECTIVES

The aim of this study is to assess the early and mid-term outcomes of open surgical repair (OR) for popliteal artery aneurysm (PAA) with prosthetic grafts.

MATERIALS AND METHODS

The pre-, intra-, and postoperative data of all patients who underwent PAA OR with prosthetic grafts at our Institution between January 2009 and July 2019 were included in a prospectively maintained database which was retrospectively analysed. Primary patency was defined as uninterrupted flow (<50% stenosis) in the graft with no additional procedures performed. Secondary patency was defined as the restoration of graft patency.

RESULTS

Eighty-two patients underwent OR for 104 PAA (age: 71, 67-78; 82 males) with prosthetic grafts. Seventy-two aneurysms (68%) were asymptomatic. The median diameter was 30mm (24-37). A medial approach was used in 35 aneurysms (34%) while a posterior approach (PA) in 69 (65%). Repairs either consisted of aneurysmectomy or aneurysm ligation without removal with an interposition graft with end-to-end anastomoses. Median operative time was 120 (103-142) minutes. The estimated blood loss (EBL) was 281 (150-281) ml. Only one patient treated by PA sustained a permanent peroneal nerve lesion, and a second patient treated via the same approach needed a surgical revision due to bleeding on postoperative day two. No temporary lesions were recorded. There were no early amputations. No perioperative deaths occurred. The median length of stay (LOS) was 3 (3-4) days. An expanded poly-tetra-flour-ethylene graft was used in 102 cases (98%) and a Dacron graft in the remain two cases (2%). As for the caliber, the 8mm graft was used in 64 cases (62%). Median follow-up was 34.6 (8.5-62.7) months. There was no related mortality. Nineteen PAA underwent reintervention with primary and secondary rate patency of 78% and 88% at three years. The median time to reintervention was 28.3 months.

CONCLUSIONS

Popliteal artery aneurysms open repair with prosthetic grafts are safe and feasible, with good mid-term results and satisfactory primary and secondary patency at three years.

Natural history, growth rates, and treatment of popliteal artery aneurysms

BACKGROUND

The natural history of a cohort of patients monitored for popliteal artery aneurysms (PAAs) has not been well described. A prevailing uncertainty exists regarding the optimal surveillance strategies and timing of treatment. The primary aim of the present study was to describe the care trajectory of all patients with PAAs identified at two tertiary vascular centers, both in surveillance and eventually treated. The secondary aim was to define the PAA growth rates.

METHODS

A retrospective, multicenter cohort study was performed of all patients with PAAs at two vascular centers in two countries (Sweden, 2009-2016; New Zealand, 2009-2017). Data were collected from electronic medical records regarding the comorbidities, treatment, and outcomes and analyzed on a patient- and extremity-specific level. Treatment was indicated at the occurrence of emergent symptoms or considered at a PAA threshold of >2 cm. The PAAs were divided into small (≤15 mm) and large (>15 mm) aneurysms. The mean surveillance follow-up was 5.1 years.

RESULTS

Most of the 241 identified patients (397 limbs) with a diagnosis of PAAs had bilateral aneurysms (n = 156). Most patients were treated within the study period (163 of 241; 68%), and one half of the diagnosed extremities with PAA had been treated (54%; 215 of 397). Among those who had undergone elective repair, treatment had usually occurred within 1 year after the diagnosis (66%; 105 of 158). More small PAAs were detected in the group that had required emergent repair compared with elective repair (6 of 57 [11%] vs 12 of 158 [8%]; P < .001). No differences were found in the mean diameters between the elective and emergent groups (30.1 mm vs 32.2 mm; P = .39). Growth was recorded in 110 PAAs and on multivariate analysis was associated with a larger index diameter (odds ratio, 1.138; 95% confidence interval, 1.040-1.246; P = .005) and a concurrent abdominal aortic aneurysm (odds ratio, 2.553; 95% confidence interval, 1.018-6.402; P = .046).

CONCLUSIONS

The present cohort of patients represented a true contemporary clinical setting of monitored PAAs and showed that most of these patients will require elective repair, usually within 1 year. The risk of emergent repair is not negligible for patients with smaller diameter PAAs. However, the optimal selection strategy for preventive early repair is still unknown. Future morphologic studies are needed to support the development of individualized surveillance protocols.

A Divide between the Western European and the Central and Eastern European Countries in the Peripheral Vascular Field: A Narrative Review of the Literature

Thirty years after the transition period, starting from 1989, Central and Eastern European countries (CEECs), representing one-fifth of the entire European population, share many historical, societal, political, economic, and cultural characteristics. Although accumulating data on coronary heart diseases and cerebrovascular diseases support these observations, in the case of peripheral arterial disease, data are scarce. The present review attempts to summarise the shreds of data that may highlight a divide in this field between CEECs and Western European countries. Disparities in risk factors and peripheral vascular care across Europe seem to be tangible and can be seen as a signal of existing differences. Improvements in research and development and the collection and cross-border share of scientific data are essential to initiate and facilitate convergence in this field.

Off-Label Use of a Double-Layer Micromesh Carotid Stent for Hybrid Treatment of Popliteal Artery Aneurism Complicated by Chronic Distal Embolization

We report our initial experience in off-label use of the double-layer micromesh (DLM) Roadsaver® stent for the hybrid treatment of a fusiform popliteal artery aneurism complicated by distal embolization and chronic limb threatening ischemia in a COVID-19-positive young male. A 36-year-old male patient was admitted with chronic limb threatening ischemia of the left lower limb. The duplex ultrasound and computer tomography angiography (CTA) demonstrated a fusiform popliteal artery aneurism with a maximal diameter of 14 mm and distal occlusion of peroneal and both tibial arteries. Urgent hybrid intervention was performed, starting with an open thrombectomy from the distal posterior tibial artery via a retromalleolar access followed by percutaneous deployment of the DLM Roadsaver® stent (Terumo, Tokyo, Japan) for the exclusion of the popliteal artery aneurism. The flow diverting effect was observed immediately with contrast stagnation in the asymmetrical part of the aneurism sac (grade C2 of the O'Kelly-Marotta flow diversion scale). The procedure was uneventful, with the regaining of an adequate foot perfusion and palpable pulse at the posterior tibial artery. On the 2^nd postoperative day, the patient was diagnosed with a symptomatic form of COVID-19 infection and transferred to a dedicated facility. At a one-month follow-up, the patient had no symptoms of limb ischemia and CTA showed complete thrombosis of the aneurism sac, absence of endoleaks, and patency of the treated arterial segment. This case demonstrates the possibility of off-label use of the DLM Roadsaver® stent for hybrid treatment of popliteal artery aneurism complicated by distal embolization and critical limb ischemia.

Adherence to instruction for use after endovascular repair of popliteal artery aneurysm

OBJECTIVES

Endovascular repair (ER) of popliteal artery aneurysm (PAA) is an alternative to open repair. However, there is no standardized protocol for when to opt for ER and the decision is therefore at the discretion of the clinician. This study aims to evaluate the adherence to the Instruction For Use (IFU) in patients undergoing ER for PAA and factors associated with stent graft patency at one year.

METHODS

The adherence to IFU provided by the manufacturer in 55 patients treated with Gore Viabahn® Endoprosthesis with Heparin Bioactive Surface for PAA between 2009 and 2019 were retrospectively analyzed. Duplex follow-up was performed at 30 days and one year.

RESULTS

The two groups of patients treated within (n = 10) and not within (n = 45) IFU did not differ in patient demographics, diagnostic assessment, treatment or outcome. Forty-five patients (81.8%) received stent graft placement with at least one deviation according to IFU. Distal oversizing >20% was the most frequent deviation against IFU (n = 22, 40.0%). Primary patency at one year was 72%. Diameter size difference >1 mm between overlapping stent grafts (6/14 [43%], p = 0.013) and renal insufficiency (5/12 [42%], p = 0.0086) were associated with lower primary patency at one year. Age-adjusted analysis of tortuosity index (HR 1.78/SD, 95% CI 1.17-2.71; p = 0.0071) and maximal PAA angle (HR 1.73/SD, 95% CI 1.018-2.95; p = 0.043) were associated with major amputation/mortality at end of follow-up.

CONCLUSION

The majority of patients undergoing ER for PAA were not treated within IFU. Diameter size difference >1 mm between overlapping stent grafts was associated with a higher loss of primary patency at one year. Multi-center studies with larger sample size and long-term follow up of patency are warranted.

Results After Open and Endovascular Repair of Popliteal Aneurysm: A Matched Comparison Within a Population Based Cohort

OBJECTIVE

To identify factors affecting the outcome after open surgical (OSR) and endovascular (ER) repair of popliteal artery aneurysm (PA) in comparable cohorts.

METHODS

A matched comparison in a national, population based cohort of 592 legs treated for PA (2008 - 2012), with long term follow up. Registry data from 899 PA patients treated in 2014 - 2018 were analysed for time trends. The 77 legs treated by ER were matched, by indication, with 154 legs treated with OSR. Medical records and imaging were collected. Analysed risk factors were anatomy, comorbidities, and medication. Elongation and angulations were examined in a core lab. The main outcome was occlusion.

RESULTS

Patients in the ER group were older (73 vs. 68 years, p = .001), had more lung disease (p = .012), and were treated with dual antiplatelet therapy or anticoagulants more often (p < .001). The hazard ratio (HR with 95% confidence intervals) for occlusion was 2.69 (1.60 - 4.55, p < .001) for ER, but 3.03 (1.26 - 7.27, p = .013) for poor outflow. For permanent occlusion, the HR after ER was 2.47 (1.35 - 4.50, p = .003), but 4.68 (1.89 - 11.62, p < .001) for poor outflow. In the ER subgroup, occlusion was more common after acute ischaemia (HR 2.94 [1.45 - 5.97], p = .003; and poor outflow HR 14.39 [3.46 - 59.92], p < .001). Larger stent graft diameter reduced the risk (HR 0.71 [0.54 - 0.93], p = .014). In Cox regression analysis adjusted for indication and stent graft diameter, elongation increased the risk (HR 1.020 per degree [1.002 - 1.033], p = .030). PAs treated for acute ischaemia had a median stent graft diameter of 6.5 mm, with those for elective procedures being 8 mm (p < .001). Indications and outcomes were similar during both time periods (2008 - 2012 and 2014 - 2018).

CONCLUSION

In comparable groups, ER had a 2.7 fold increased risk of any occlusion, and 2.4 fold increased risk of permanent occlusion, despite more aggressive medical therapy. Risk factors associated with occlusion in ER were poor outflow, smaller stent graft diameter, acute ischaemia, and angulation/elongation. An association between indication, acute ischaemia, and small stent graft diameter was identified.