Part one: For the motion asymptomatic popliteal artery aneurysms (less than 3 cm) should be treated conservatively

Intraluminal thrombus volume correlates with the crural vessel runoff in popliteal artery aneurysms upon initial presentation

Background: Patients having emergency surgery due to ischemia caused by a popliteal artery aneurysm (PAA) have worse outcomes in all endpoints (operation time, major adverse limb events (MALE), amputation-free survival) than after elective treatment, mostly due to a limited crural vessel runoff. This study investigates the relationship between PAA diameter, volume, and luminal thrombus load in relation to the preoperative crural runoff. Patients and methods: Retrospective single-centre evaluation of surgically treated patients with PAA and semi-automated quantitative CT analysis of PAA morphologies (diameter, volume and intraluminal thrombus volume). Primary endpoints were the correlations these characteristics with the number of patent crural vessels. Results: A total of 89 PAAs (61 patients, median age 75, IQR 12; 94.4% male) were identified, of which 47.2% were symptomatic with 18 acute limb ischemia (ALI). The diameter at surgery was 33.8 ± 12.1mm and the volume 68.5 ± 13.6mm3. A median of two lower leg vessels were patent (elective 3 [1, 2, 3] vs. emergency 1 [1, 2], p=0.1) upon preoperative CTA. 77 PAAs underwent elective surgery, five PAAs (5.6%) received endovascular treatment. The surgical complication rate was 23.6% without immediate or early occlusion. The follow-up was 42.5 [39-45] months. The overall mortality rate was 11.2% and the primary patency rate 73.9%. While the total aneurysm volume correlated well with the diameter (r=0.77, p<0.01), the intraluminal thrombus volume (ILT) showed the clearest correlation with the crural runoff (r=-0.34, p=0.01). No correlation between the diameter and crural runoff was observed (r=-0.17, p=0.1). A reduced crural run-off was significantly associated with impaired amputation-free survival (p=0.01). A subgroup analysis (n=21) with sequential CTs showed a tendency towards greater increase of thrombus volume compared to plain diameter during PAA growth. The thrombus volume index (=ILT/total PAA volume) was significantly higher in emergency patients (p=0.01), while diameters tended to be smaller (p=0.57). Conclusions: The increasing intraluminal thrombus volume correlates most distinctly with a reduced crural runoff in PAAs and should therefore be considered prognostically important, especially in the presence of an increased growth rate compared to the diameter.

Elective Surgical Repair of Popliteal Artery Aneurysms with Posterior Approach vs. Endovascular Exclusion: Early and Long Term Outcomes of Multicentre PARADE Study

OBJECTIVE

The aim of this study was compare elective surgical repair of popliteal artery aneurysms (PAAs) via a posterior approach vs. endovascular exclusion, analysing early and five year outcomes in a multicentre retrospective study.

METHODS

Between January 2010 and December 2023, a retrospectively maintained dataset of all consecutive asymptomatic PAAs that underwent open repair with posterior approach or endovascular repair in 37 centres was investigated. An aneurysm length of ≤ 60 mm was considered the only inclusion criterion. A total of 605 patients were included; 440 PAAs (72.7%) were treated via a posterior approach (open group) and the remaining 165 PAAs (27.3%) were treated using covered stents (endo group). Continuous data were expressed as median with interquartile range. Thirty day outcomes were assessed and compared. At follow up, primary outcomes were freedom from re-intervention, secondary patency, and amputation free survival. Secondary outcomes were survival and primary patency. Estimated five year outcomes were compared using log rank test.

RESULTS

At 30 days, no differences were found in major morbidity, mortality, graft occlusion, or re-interventions. Three patients (0.7%) in the open group experienced nerve injury. The overall median duration of follow up was 32.1 months. At five year follow up, freedom from re-intervention was higher in the open group (82.2% vs. 68.4%; p = .021). No differences were observed in secondary patency (open group 90.7% vs. endo group 85.2%; p = .25) or amputation free survival (open group 99.0% vs. endo group 98.4%; p = .73). A posterior approach was associated with better survival outcomes (84.4% vs. 79.4%; p = .050), and primary patency (79.8% vs. 63.8%; p = .012).

CONCLUSION

Early and long term outcomes following elective repair of PAAs measuring ≤ 60 mm via a posterior approach or endovascular exclusion seem comparable. Nerve injury might be a rare but potential complication for those undergoing open surgery. Endovascular repair is associated with more re-interventions.

Bypass Patency and Amputation-Free Survival after Popliteal Aneurysm Exclusion Significantly Depends on Patient Age and Medical Complications: A Detailed Dual-Center Analysis of 395 Consecutive Elective and Emergency Procedures

Background/Objectives: A popliteal artery aneurysm (PAA) is traditionally treated by an open PAA repair (OPAR) with a popliteo-popliteal venous graft interposition. Although excellent outcomes have been reported in elective cases, the results are much worse in cases of emergency presentation or with the necessity of adjunct procedures. This study aimed to identify the risk factors that might decrease amputation-free survival (efficacy endpoint) and lower graft patency (technical endpoint). Patients and Methods: A dual-center retrospective analysis was performed from 2000 to 2021 covering all consecutive PAA repairs stratified for elective vs. emergency repair, considering the patient (i.e., age and comorbidities), PAA (i.e., diameter and tibial runoff vessels), and procedural characteristics (i.e., procedure time, material, and bypass configuration). Descriptive, univariate, and multivariate statistics were used. Results: In 316 patients (69.8 ± 10.5 years), 395 PAAs (mean diameter 31.9 ± 12.9 mm) were operated, 67 as an emergency procedure (6× rupture; 93.8% severe acute limb ischemia). The majority had OPAR (366 procedures). Emergency patients had worse pre- and postoperative tibial runoff, longer procedure times, and more complex reconstructions harboring a variety of adjunct procedures as well as more medical and surgical complications (all p < 0.001). Overall, the in-hospital major amputation rate and mortality rate were 3.6% and 0.8%, respectively. The median follow-up was 49 months. Five-year primary and secondary patency rates were 80% and 94.7%. Patency for venous grafts outperformed alloplastic and composite reconstructions (p < 0.001), but prolonged the average procedure time by 51.4 (24.3-78.6) min (p < 0.001). Amputation-free survival was significantly better after elective procedures (p < 0.001), but only during the early (in-hospital) phase. An increase in patient age and any medical complications were significant negative predictors, regardless of the aneurysm size. Conclusions: A popliteo-popliteal vein interposition remains the gold standard for treatment despite a probably longer procedure time for both elective and emergency PAA repairs. To determine the most effective treatment strategies for older and probably frailer patients, factors such as the aneurysm size and the patient's overall condition should be considered.

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.

Nationwide cross-sectional epidemiological analysis of 3,306 lower limb peripheral aneurysm repairs in Brazilian public hospitals between 2008 and 2019: trends, mortality and costs

BACKGROUND

Although peripheral aneurysms can be limb or life threatening, the literature is scarce and there are only two large population-based epidemiological studies on peripheral aneurysm repair, comprising data from high-income countries only.

OBJECTIVE

To evaluate the epidemiology of peripheral aneurysm repairs in the Brazilian Public Health System, which exclusively insures more than 160 million Brazilians.

METHODS

retrospective cross-sectional analysis on open and endovascular peripheral aneurysm repairs performed in public hospitals between 2008 and 2019 using a public database.

RESULTS

3,306 peripheral aneurysm repairs were observed. Most patients were elderly (57.74%) male (72.66%) and patients treated with endovascular repair were older (p=0.008). Most repairs were emergency (59.56%) and open (93.8%) and there was an overall downward trend in procedure rates. We observed a decreasing predominance of emergency open repair over elective open repair (p<0.001), but open repairs prevailed over endovascular procedures, with no tendency to change this predominance. Mortality rates were 3.12% and 3.67% after elective and emergency open repair, respectively, with no difference, and 0 and 4.24% for elective and emergency endovascular repair, respectively. The government reimbursed an average of $1170.05 for open PA repair and $1802.01 for endovascular repair.

CONCLUSIONS

We presented the largest series of the literature analyzing all 3,306 lower limb peripheral aneurysm repairs performed in public hospitals in a middle-income country. Procedure rates tended to decrease. Open repair predominated. Mortality rates ranged from 0 to 4%. Most procedures were emergency, but there was a relative increase of elective treatments over the years.

Popliteal artery aneurysms treatments: early midterm results of the use of endovascular stent grafts

Background/aim

Popliteal artery aneurysms (PAAs) are abnormal bulgings, which account for 70% of all peripheral artery aneurysms. They are usually asymptomatic. In this study, we present our long-term results of endovascular stent grafts in the treatment of PAA in the light of literature data.

Material and methods

A total of 63 legs of 63 patients with PAA, who were treated with endovascular techniques in our clinic between July 2010 and July 2019, were retrospectively analyzed. All patients underwent color Doppler ultrasound (DUS), magnetic resonance angiography (MRA), or computed tomography angiography (CTA) to identify the diameter and length of PAAs, vessel tortuosity, the presence and degree of thrombus, and diameter in the healthy landing zone and to visualize tibioperoneal vascular structures. A Viabahn stent graft was inserted in all patients.

Results

57 patients (90.5%) were males with a mean age of 76.35 ± 7 years. 24 patients (38.1%) were symptomatic, while 11 patients (17.5%) had a concomitant abdominal aortic aneurysm (AAA). The mean follow-up period was 46.05 ± 25.01 months. The primary patency rate was 79.3%. A graft thrombosis was observed in 13 patients (20.6%) during a mean follow-up period of 8.31 ± 5.91 months. The number of distal arteries was significantly lower in the patients with thrombosis than those without.

Conclusions

Endovascular treatment of PAA using stentgrafts is safe in selected cases. However, it is reasonable to avoid endovascular treatment due to an increased risk for thrombosis in patients with a low number of patent distal arteries or impaired distal flow.

Outcomes of popliteal artery aneurysms treated by ligation and in situ saphenous vein bypass

BACKGROUND

Modality of elective repair (open or endovascular) of popliteal artery aneurysms (PAAs) is still debated. About open repair no strict evidence exists about the best surgical technique. The aim of this study was to report a 20-year experience with ligation and in situ saphenous vein bypass for the elective treatment of PAAs.

METHODS

A retrospective review of consecutive patients who underwent elective open surgical PAA repair in our center between January 2001 and April 2020 was performed. Ninety-two limbs in 84 patients underwent a PAA ligation and in situ saphenous bypass. Early (30 day) outcomes were assessed. Estimated 5-year outcomes according to Kaplan-Meier curves in terms of primary patency, primary assisted patency, secondary patency, and limb salvage were evaluated. Associations of patient and procedure variables with patency and limb salvage outcomes were sought with multivariate analysis.

RESULTS

Patients were predominantly male (80/84, 95.2%) with a mean age of 73.1 years (range 50-89). In all cases technical success was obtained. The mean hospital stay was 5.8 days (range 2-27). Thirty-day overall mortality (n=1) and major amputation (n=1) rates were both 1.2%. Mean duration of follow-up was 31.3 months (range 1-168). At 5 years estimated rates of primary patency, primary assisted patency, secondary patency, and limb salvage were 76.3%, 81.5%, 89.9%, and 96.6%, respectively. On multivariate analysis the associations were: primary patency with PAA diameter >30 mm (P=.007), and poor run-off status (P<.001); primary assisted patency with poor run-off status (P<.001); secondary patency with poor run-off status (P=.04). Major amputation had no independent predictors of poor outcomes.

CONCLUSIONS

Elective surgical treatment of PAAs with ligation and in situ saphenous vein bypass is safe, effective and urable with good 5-year outcomes in terms of overall patency and limb salvage. Poor run-off status seemed to be an independent predictor of worse patency rates. This surgical technique should be cautiously applied in patients with PAAs with a diameter >30 mm.

Treatment of bilateral popliteal artery aneurysms

Popliteal artery aneurysms are the most frequent type of peripheral aneurysm, accounting for 85% of the all of these aneurysms. Usually asymptomatic, they are generally diagnosed during clinical examination. Incidence is higher among males and seniors. They are bilateral in 50% of the cases and 60% are associated with abdominal aortic aneurysms. This paper describes a 72-year-old male patient who presented with two bilateral pulsatile masses, one in each popliteal region, was otherwise asymptomatic, and had a history of hypertension and dyslipidemia. Clinical examination and ultrasound imaging confirmed a diagnosis of bilateral aneurysms of the popliteal arteries. Popliteal artery aneurysms can be treated with open bypass surgery, with or without aneurysm resection, or with endovascular surgery. This Therapeutic Challenge discusses these possibilities.

Patients with abdominal aortic aneurysm have a high prevalence of popliteal artery aneurysms

Patients with abdominal aortic aneurysms (AAA) are more prone to develop popliteal artery aneurysms (PAA), but the prevalence is not well known. Our aim was to investigate the prevalence of PAA in patients with AAA, and to determine whether a certain risk factor profile is more commonly found in patients with concurrent aneurysms. All AAA patients (ICD code I71.3, I71.4) attending the outpatient clinic at the Karolinska University Hospital between 2011 and 2013 were included in the study cohort ( n=465); 48% (225) had been subjected to an ultrasound or computed tomography scan of their popliteal arteries. In these patients, three definitions of PAA were considered (⩾ 10.5, ⩾ 12, ⩾ 15 mm), although the overall analysis is based on PAA ⩾ 12 mm. The mean age was 70.7 years (SD 7.5), 89% were men, and the mean AAA diameter was 47 mm (SD 14). The prevalence of PAA was 19% ( n=43) by definition ⩾ 12 mm, and 11% ( n=25) with 15 mm. Claudication was more frequently found in AAA patients with PAA than patients without PAA. Sensitivity between clinical examination and radiology was 26%, and the specificity for clinical examination was 90%. In conclusion, owing to the high prevalence of PAA in AAA patients, described by us and others, the low cost and risks associated with ultrasound and the poor sensitivity at clinical examination, all women and men with AAA should undergo one radiological examination of their popliteal arteries.

Giant popliteal artery aneurysm: case report and review of the literature

Popliteal artery aneurysms (PAAs) are rare in general population but represent the second most common peripheral arterial aneurysms following those located in the aortoiliac segment. They usually affect men over 60 years old with established cardiovascular disease caused by atherosclerosis. Other more unusual conditions such as trauma, congenital popliteal aneurysm, mycotic aneurysm, inflammatory arteritis, or popliteal entrapment are responsible. The authors report the first ever case of a male diagnosed with chronic renal failure with giant popliteal artery aneurysm. We have successfully resected the aneurysm and revascularized with synthetic graft.