Part two: Against the motion asymptomatic popliteal artery aneurysms (less than 3 cm) should be repaired

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.

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.

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.

Excretory-secretory product of third-stage Gnathostoma spinigerum larvae induces apoptosis in human peripheral blood mononuclear cells

Human gnathostomiasis caused by third-stage Gnathostoma spinigerum larvae (G. spinigerum L3) is an important zoonotic disease in tropical areas of the world. The excretory-secretory products (ES) that are excreted by infective larva play a significant role in host immune evasion and tissue destruction. To investigate the poorly understood mechanisms of G. spinigerum L3 pathogenesis, we focused on the potential effect of ES on inducing apoptosis in human immune cells by using human peripheral blood mononuclear cells (PBMCs) as a model. Early and late apoptosis of PBMCs were assessed following the exposure of these cells to G. spinigerum L3 ES (0.1, 0.5, and 1.0 μg/ml) for 6-48 h. The apoptotic cells were identified by flow cytometric staining of PBMC with FITC-annexin V and propidium iodide. The expression of regulatory genes related to apoptosis mechanisms in ES-treated PBMCs was investigated using a Human Apoptosis RT² Profiler™ PCR Array. The results showed significant levels of early phase apoptosis at 18 h and of late phase apoptosis at 24 h. We speculate that this apoptosis in PBMCs occurs via the extrinsic pathway. Apoptosis in the ES-induced PBMCs was observed as quickly as 90 min after exposure, and the highest effect was observed at 18-24 h. Furthermore, ES can trigger apoptosis lasting for 48 h. Our findings expand the understanding of one of the mechanisms involved, immune-evasive strategy mechanism used by G. spinigerum larvae during human gnathostomiasis.