Stent fractures in the Hemobahn/Viabahn stent graft after endovascular popliteal aneurysm repair

Disappointing results of popliteal aneurysm endovascular treatment with a new self-expandable covered stent

PURPOSE

To describe our clinical experience of endovascular exclusion of popliteal artery aneurysms using the new self-expandable covered stent SOLARIS® (Scitech Medical, Brazil), and to report its results in the context of surgical and endovascular treatment of popliteal artery aneurysms.

CASE REPORT

Among 20 popliteal artery aneurysms undergoing open or endovascular repair in 2022 and 2023, two patients were successfully treated with the Solaris stentgraft. Both patients had a patent popliteal artery and three run-off vessels. After stentgraft implantation, they received dual antiplatelet therapy for three months and they were followed-up with Duplex scan and clinical evaluation after three months, and every six months thereafter. After three months, one Solaris stentgraft had complete thrombosis and the other ruptured, requiring surgical removal. No complications were observed among the other aneurysms treated with open repair or with the Viabahn® stentgraft.

CONCLUSIONS

Endovascular treatment of popliteal aneurysms with the new covered self-expandable stent Solaris resulted in severe complications in the two cases reported, and in worse short-term outcomes than endovascular repair with Viabahn® and open repair. Its off-label use to treat popliteal artery aneurysms should be therefore discouraged.

Outcomes of popliteal stent-graft placement at the artery hinge point for popliteal artery aneurysm

OBJECTIVES

to assess whether stent-grafts crossing the hinge point (HP) in the popliteal artery are associated with increased complications and decreased patency rates, after endovascular treatment of the popliteal artery aneurysm.

METHODS

This was a single-center, case-control study. Patients were allocated to either the HP group (subjects with stent-grafts crossing the HP) or the control group (subjects with stent-grafts above and/or below the HP) based on stent-graft location in the femoropopliteal artery. HP was defined as the main curve in the popliteal artery in the most acute angle toward the femur that appeared during knee flexion, which was identified by reviewing post-operative angiograms. Independent, blinded reviews were performed for all imaging data. Graft evaluation by CTA or duplex ultrasound was performed at 1, 3, 6, and 12 months and annually thereafter. Outcomes measured included: stent-graft patency, stent-graft fracture, other stent-related complications, and major adverse events, including reintervention, death, amputation, stroke, and myocardial infarction.

RESULTS

A total of 44 limbs treated with placement of heparin-bonded Viabahn endoprostheses were included in this study. Twenty and Twenty Four patients were allocated to the HP group and the control group, respectively. Primary patency rates of the HP group at 1, 2, 3, and 5 years were 84.1±8.4%, 84.1±8.4%, 84.1±8.4%, and 72.1±13.3%, respectively. The primary patency rates of the control group were 87.0±7.0%, 82.4±8.0%, 82.4±8.0%, and 82.4±8.0%, respectively. There was no significant difference between the two groups (P=0.81). No reintervention was performed in the control group. In the HP group, 5 limbs (25.0%) developed endoleak, 3 (15.0%) developed thrombosis, and one (5.0%) developed a stent fracture followed by thrombosis. Thrombosis occurred in 2 limbs (8.3%) of the control group, and stent-graft migration was observed in another 2 cases (8.3%). Neither group demonstrated stent-graft infection or acute popliteal artery embolism. Overall, incidence of stent-related complications were significantly higher in the HP group (P=0.04). Event-free survival rates of the HP group at 1, 2, 3, and 5 years were 75.0±9.7%, 69.6±10.4%, 61.9±11.8%, and 29.0±12.8%, respectively. Corresponding rates in the control group were 79.2±8.3%, 79.2±8.3%, 79.2±8.3%, and 79.2±8.3%, respectively. The difference was not statistically significant between the two groups (P=0.20) CONCLUSIONS: crossing the HP with femoropopliteal artery stent-grafts increased the risk of stent-related complications and reinterventions but did not decrease stent patency or event-free survival.

Fracture of a covered stent-graft due to heterotopic ossification of residual hematoma after endovascular treatment of superficial femoral artery pseudoaneurysm: A case report

RATIONALE

Endovascular treatment (EVT) is considered a preferred procedure of superficial femoral artery (SFA) pseudoaneurysm in recent years. However, heterotopic ossification (HO) after SFA pseudoaneurysm is a rare occurrence, that may cause late stent-graft fracture.

PATIENT CONCERNS

A 58-year-old male who underwent EVT for SFA pseudoaneurysm 8 years ago presented with a progressive mass at the right thigh and claudication. Computed tomography angiography (CTA) showed fracture and occlusion of stent-graft, which was compressed by the deep femoral artery (DFA) pseudoaneurysm and a bone-like body.

DIAGNOSIS

According to the CTA images, the stent-graft was fractured and occluded, accompanied by DFA pseudoaneurysm.

INTERVENTIONS AND OUTCOMES

Debridement and arterial reconstruction were performed. Pathological analysis showed that the bone-like body was derived from HO. CTA at one-year follow-up showed that the prosthetic vessel was patent and previous hematoma disappeared.

CONCLUSIONS

This report demonstrates that residual hematoma can induce HO, which may result in late stent fracture, and it should thus be removed timely. Patients with SFA pseudoaneurysm who have undergone EVT should be followed up regularly.

Late Vascular Injury at Both Edges of the VIABAHN Stent Graft after Endovascular Repair for Idiopathic Superficial Femoral Artery Rupture

The VIABAHN stent graft is often used for traumatic and iatrogenic vascular injuries. In this case, vascular injury at both edges of the VIABAHN stent graft was noted 4 months after endovascular repair for idiopathic superficial femoral artery (SFA) rupture. The longitudinal compression of the SFA with a decrease in hematoma size was assumed to exceed the flexibility of the stent graft. Thus, the use of stent grafts for vascular injuries with giant pseudoaneurysms may result in late vascular injuries at both edges of the stent graft. Therefore, cautious assessment of its indications and strict surveillance are required.

Poor runoff and distal coverage below the knee are associated with poor long-term outcomes following endovascular popliteal aneurysm repair

OBJECTIVE

Reports of good short-term outcomes for endovascular repair of popliteal artery aneurysms have led to an increased use of the technique. However, data are lacking on long-term limb-related outcomes and factors associated with the failure of endovascular repair.

METHODS

All patients who underwent endovascular popliteal aneurysm repair (EPAR) at a single institution from January 2006 to December 2018 were included in the study. Demographics, indications, anatomic and operative details, and outcomes were reviewed. Long-term patency, major adverse limb event-free survival (MALE-FS) and graft loss/occlusion were analyzed with multivariable cox regression analysis and Kaplan-Meier curves.

RESULTS

We included 117 limbs from 101 patients with a mean follow-up of 55.6 months (range, 0.43-158 months). The average age was 73 ± 9.3 years. Thirty-two patients (29.1%) were symptomatic (claudication, rest pain, tissue loss, or rupture). The stent grafts crossed the knee joint in 91.4% of cases. In all, 36.8% of procedures used one stent graft, 41.0% used two stent grafts, and 22.2% of procedures used more than two stent grafts. The median arterial length covered was 100 mm, with an average length of stent overlap of 25 mm. Tapered configurations were used in 43.8% of cases. The majority of limbs (62.8%) had a three-vessel runoff, 20.2% had a two-vessel runoff, and 17% has a one-vessel runoff. The Kaplan-Meier estimates of graft occlusion at 1 and 3 years were 6.3% and 16.2%, respectively. The 1- and 3-year primary patency rates were 88.2% and 72.6%, and the 1- and 3-year major adverse limb event-free survival (MALE-FS) rates were 82% and 57.4%. The 1- and 3-year survival rates were 92.9% and 76.2%, respectively. On multivariable Cox regression, aneurysm size, one-vessel runoff, and coverage below the knee were associated with a lower 3-year MALE-FS. Coverage below the knee was also associated with a lower 3-year MALE-FS. Other anatomic or technical details were not associated with limb-related events or patency.

CONCLUSIONS

This study is the largest single center analysis to describe the predictors of poor outcomes after EPAR. EPAR is a safe and effective way to treat popliteal artery aneurysms. Factors associated with poor MALE-FS after EPAR include single-vessel tibial runoff and coverage below the knee.

Patient-specific computational fluid dynamics of femoro-popliteal stent-graft thrombosis

Intra-stent thrombosis is one of the major failure modes of popliteal aneurysm endovascular repair, especially when the diseased arterial segment is long and requires overlapping stent-grafts having different nominal diameters in order to accommodate the native arterial tapering. However, the interplay between stent sizing, post-operative arterial tortuosity, luminal diameter, local hemodynamics, and thrombosis onset is not elucidated, yet. In the present study, a popliteal aneurysm was treated with endovascular deployment of two overlapped stent-grafts, showing intra-stent thrombosis at one-year follow-up examination. Patient-specific computational fluid-dynamics analyses including straight- and bent-leg position were performed. The computational fluid-dynamics analysis showed that the overlapping of the stent-grafts induces a severe discontinuity of lumen, dividing the stented artery in two regions: the proximal part, affected by thrombosis, is characterized by larger diameter, low tortuosity, low flow velocity, low helicity, and low wall shear stress; the distal part presents higher tortuosity and smaller lumen diameter promoting higher flow velocity, higher helicity, and higher wall shear stress. Moreover, leg bending induces an overall increase of arterial tortuosity and reduces flow velocity promoting furtherly the luminal area exposed to low wall shear stress.

Open repair with resection and reimplantation for popliteal artery aneurysm

Popliteal artery aneurysms are the most frequent type of peripheral arterial aneurysm and can be repaired by either open or endovascular techniques. An 81-year-old man presented with leg swelling and during duplex ultrasound examination was diagnosed a popliteal aneurysm. The transverse diameter was 3.6 × 4.5cm, length 2.8cm, one run-off vessel patent. The popliteal aneurysm was asymptomatic for clinical signs of limb ischaemia. We opted for an open surgical repair through a posterior approach. During dissection of the popliteal artery above and below the aneurysm, the two non-diseased popliteal extremities appeared to be very close, leading to the decision to perform an end-to-end anastomosis between the two arterial extremities. The patient was discharged after three days with no adverse events. Follow-up consisted of duplex ultrasound examination at one, three and six months, and then annually. At the six-month follow-up there was no restenosis at the anastomosis.

Progressive stenosis of a popliteal artery stent graft by laminated thrombus

We present a case of failed popliteal artery aneurysm repair using a Viabahn stent graft (W. L. Gore & Associates, Flagstaff, Ariz) due to laminated thrombus formation. A 75-year-old man presented with a symptomatic popliteal artery aneurysm. He was treated with a Viabahn stent graft. On follow-up, the patient complained of lower extremity claudication, and duplex ultrasound examination showed a focal intrastent stenosis. A computed tomography scan showed a significant stenosis within the stent graft, at the level of the knee joint creases. The patient underwent superficial femoral artery to distal popliteal surgery. This case report aims to expand on the mechanism of stent graft failure in popliteal aneurysms.

Endovascular versus open repair of asymptomatic popliteal artery aneurysm

BACKGROUND

Popliteal artery aneurysm (PAA) is a focal dilatation and weakening of the popliteal artery. If left untreated, the aneurysm may thrombose, rupture or the clot within the aneurysm may embolise causing severe morbidity. PAA may be treated surgically by performing a bypass from the arterial segment proximal to the aneurysm to the arterial segment below the aneurysm, which excludes the aneurysm from the circulation. It may also be treated by a stent graft that is inserted percutaneously or through a small cut in the groin. The success of the procedure is gauged by the ability of the graft to stay patent over an extended duration. While surgical treatment is usually preferred in an emergency, the evidence on first line treatment in a non-emergency setting is unclear. This is an update of a review first published in 2014.

OBJECTIVES

To assess the effectiveness of an endovascular stent graft versus conventional open surgery for the treatment of asymptomatic popliteal artery aneurysms (PAA) on primary and assisted patency rates, hospital stay, length of the procedure and local complications.

SEARCH METHODS

The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase and CINAHL databases and World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers to 29 January 2019.

SELECTION CRITERIA

We included all randomised controlled trials (RCTs) comparing endovascular stent grafting versus conventional open surgical repair in patients undergoing unilateral or bilateral prophylactic repair of asymptomatic PAAs.

DATA COLLECTION AND ANALYSIS

We collected data on primary and assisted primary patency rates (primary endpoints) as well as operating time, the length of hospital stay, limb salvage and local wound complications (secondary endpoints). We presented results as risk ratio or mean difference with 95% confidence intervals and assessed the certainty of the evidence using GRADE.

MAIN RESULTS

No new studies were identified for this update. A single RCT with a total of 30 PAAs met the inclusion criteria. There was a low risk of selection bias and detection bias. However, the risks of performance bias, attrition bias and reporting bias were unclear from the study. Despite being an RCT, the certainty of the evidence was downgraded to moderate due to the small sample size, resulting in wide confidence intervals (CIs); only 30 PAAs were randomised over a period of five years (15 PAAs each in the groups receiving endovascular stent graft and undergoing conventional open surgery). The primary patency rate at one year was 93.3% in the endovascular group and 100% in the surgery group (RR 0.94, 95% CI 0.78 to 1.12; moderate-certainty evidence). The assisted patency rate at one year was similar in both groups (RR 1.00, 95% CI 0.88 to 1.13; moderate-certainty evidence). There was no clear evidence of a difference between the two groups in the primary or assisted patency rates at four years (13 grafts were patent from 15 PAA treatments in each group; RR 1.00, 95% CI 0.76 to 1.32; moderate-certainty evidence); the effects were imprecise and compatible with the benefit of either endovascular stent graft or surgery or no difference. Mean hospital stay was shorter in the endovascular group (4.3 days for the endovascular group versus 7.7 days for the surgical group; mean difference (MD) -3.40 days, 95% CI -4.42 to -2.38; P < 0.001; moderate-certainty evidence). Mean operating time was also reduced in the endovascular group (75.4 minutes in the endovascular group versus 195.3 minutes in the surgical group; MD -119.90 minutes, 95% CI -137.71 to -102.09; P < 0.001; moderate-certainty evidence). Limb salvage was 100% in both groups. Data on local wound complications were not published in the trial report.

AUTHORS' CONCLUSIONS

Evidence to determine the effectiveness of endovascular stent graft versus conventional open surgery for the treatment of asymptomatic PAAs is limited to data from one small study. At one year there is moderate-certainty evidence that primary patency may be improved in the surgery group but assisted primary patency rates were similar between groups. At four years there was no clear benefit from either endovascular stent graft or surgery to primary or assisted primary patency (moderate-certainty evidence). As both operating time and hospital stay were reduced in the endovascular group (moderate-certainty evidence), it may represent a viable alternative to open repair of PAA. A large multicenter RCT may provide more information in the future. However, difficulties in recruiting enough patients are likely, unless it is an international collaboration including a number of high volume vascular centres.

[Treatment of Peripheral Aneurysms - Dual Supera for Popliteal Artery Aneurysms: Immediate and Long-Term Results]

Popliteal aneurysms have the highest incidence of all peripheral aneurysms. The clinical symptoms are dominated by chronic embolism, resulting in irreversible ischemia with the associated risk of amputation and mortality, but rupture is less important. Acute aneurysm thrombosis bears a high risk of amputation and mortality. Endovascular exclusion with covered stents instead of open surgery has gained widespread acceptance and is based on reliable data. The principle of flow diversion for aneurysm treatment is well known for the cerebral vasculature, and is now emerging as a potential alternative with promising results and is challenging the concept of complete endovascular aneurysm exclusion or surgical bypassing. Since 2011, thirty-four out of 142 electively treated popliteal aneurysms and 8 thrombosed aneurysms were treated with a bare metal woven Nitinol stent. In this single centre series with continuous mid- to long-term follow-up, as described below, this option showed reliable results in terms of clinical outcome, material fatigue and preservation of outflow vasculature with the option for conversion. The limitation of the technique is determined by the available maximum outer stent diameter of 7.5 mm.

Fracture of a popliteal nitinol stent and pseudoaneurysm: a case report and review of the literature

There is a lack of reports onr stent fracture with pseudoaneurysm formation in the femoropopliteal artery, which can cause restenosis or occlusion of the treated arterial segment. We present a case of a large pseudoaneurysm of the popliteal artery that was observed 18 months after popliteal stenting using a self-expandable nitinol stent. We describe an endovascular approach to overcome this severe complication. Stent fractures are an often overlooked complication of femoropopliteal stenting and can be associated with serious diseases. The popliteal artery was successfully treated using self-expandable Viabahn endoprosthesis.

In Vivo Morphological Changes of the Femoropopliteal Arteries due to Knee Flexion After Endovascular Treatment of Popliteal Aneurysm

Purpose: To evaluate morphological changes of the femoropopliteal (FP) arteries due to limb flexion in patients undergoing endovascular treatment of popliteal artery aneurysms (PAAs). Materials and Methods: Seven male patients (mean age 68 years) underwent endovascular treatment of PAA with a Viabahn stent-graft between January 2013 and December 2017. During follow-up, one contrast-enhanced computed tomography angiography (CTA) scan of the lower limbs was acquired for each recruited patient. A standardized CTA protocol for acquisitions in both straight-leg and bent-leg positions was used to visualize changes in artery shape due to limb flexion. Three-dimensional reconstruction of the FP segment was performed to compute mean diameter and eccentricity of the vascular lumen and to measure length, tortuosity, and curvature of the vessel centerline in 3 arterial zones: (A) between the origin of the superficial femoral artery and the proximal end of the stent-graft, (B) within the stent-graft, and (C) from the distal end of the stent-graft to the origin of the anterior tibial artery. Results: After limb flexion, all zones of the FP segment foreshortened: 6% in zone A (p=0.001), 4% in zone B (p=0.001), and 8% in zone C (p=0.07), which was the shortest (mean 4.5±3.6 cm compared with 23.8±5.7 cm in zone A and 23.6±7.4 cm in zone B). Tortuosity increased in zone A (mean 0.03 to 0.05, p=0.03), in zone B (0.06 to 0.15, p=0.005), and in zone C (0.027 to 0.031, p=0.1). Mean curvature increased 15% (p=0.05) in zone A, 27% (p=0.005) in zone B, and 95% (p=0.06) in zone C. In all zones, the mean artery diameter and eccentricity were not significantly affected by limb flexion. Conclusion: Limb flexion induces vessel foreshortening and increases mean curvature and tortuosity of the FP segment both within and outside the area of the stent-graft.

Management of Asymptomatic Popliteal Artery Aneurysms

Popliteal artery aneurysms (PAAs) are the most common peripheral artery aneurysms. They are frequently symptomatic and are associated with high rates of morbidity and limb loss. PAA can be treated by open or endovascular means, although there are no specified recommendations guiding treatment choice. This article delineates many of the differences between open and endovascular repair of asymptomatic PAA, and highlights several key articles comparing open and endovascular repair to guide decision making. Proper diagnosis and choice of repair can lead to good outcomes in the treatment of asymptomatic PAA.

Aneurisma da artéria isquiática persistente: relato de caso de tratamento endovascular

A persistência da artéria isquiática é uma anomalia vascular congênita rara cuja principal complicação é a dilatação aneurismática. O quadro clínico pode incluir sintomas decorrentes da dilatação arterial e da isquemia, causada por trombose ou embolização distal. O tratamento dessa afecção rara conta com opções diversas que abrangem desde a ligadura do aneurisma até a correção endovascular. O presente relato descreve o caso de uma paciente do sexo feminino com queixa de tumoração pulsátil na região glútea. Foi encaminhada ao serviço de referência e realizou angiotomografia, que evidenciou persistência completa da artéria isquiática bilateralmente, com dilatação aneurismática à esquerda. A paciente foi submetida a tratamento endovascular do aneurisma, através de punção contralateral, com implante de dois stents revestidos com manutenção da perviedade distal da artéria. A manutenção da perviedade é particularmente importante nos casos da forma completa dessa variação anatômica. A paciente cursou com boa evolução.

Endovascular Treatment of Chronic Occluded Popliteal Artery Aneurysm

Critical limb ischemia may be the consequence of chronic occlusion of an aneurysm of popliteal artery. Endovascular repairs have the potential to be less invasive than open surgery and to allow the treatment, during the same procedure, of occlusive infrapopliteal diseases achieving a better distal outflow. Eleven patients with occluded popliteal artery aneurysm (PAA) underwent an endovascular repair of PAA using a new technique, by positioning of a Viabahn graft inside a bare nitinol stent, deployed at the level of aneurysm with the intent to avoid distal embolization and to assure an external scaffold for the Viabahn graft. Immediate success rate was 100%. A peroneal artery embolization occurred in 1 patient (9%) and was successfully treated by stent implantation. Four (36.4%) patients needed a below-the-knee revascularization to achieve at least 1 vessel line to the foot. Mean postoperative hospital stay was 2.6 days. At 24-month follow-up, primary patency, target lesion revascularization, and major amputation rates were 82%, 9%, and 0%, respectively. All patients are still alive at last follow-up visit. The endovascular repair with the combined use of a bare metal stent and Viabahn graft resulted in a low incidence of distal embolization and major amputation rate, with an excellent 24-month patency rate, and may offer a safe alternative to open surgery for the treatment of occluded PAAs.

Popliteal artery aneurysm treated with implantation of a covered stent graft (fluency(®)) reinforced with a nitinol stent (S.M.A.R.T. (®))

A 60-year-old man was admitted for right knee pain provoked by an enlarging popliteal artery aneurysm (PAA) after endovascular therapy for thromboembolism in the right popliteal artery. The PAA was treated with implantation of a covered stent graft (Fluency(®)); however, acute thromboembolism occurred 6 months after the intervention. Therefore, we implanted a nitinol stent (S.M.A.R.T.(®)) in the proximal part of the covered stent where the major hinge point existed in addition to a stent fracture. No vascular event occurred during 4.5 years of follow-up.

Popliteal Artery Aneurysm Repair in the Endovascular Era: Fourteen-Years Single Center Experience

To compare outcomes of popliteal artery aneurysm (PAA) repair by endovascular treatment, great saphenous vein (GSV) bypass, and prosthetic bypass.Single center retrospective analysis of patients presenting PAA from 2000 to 2013. Patients were divided into endovascular treatment (group A); GSV bypass (group B); and prosthetic graft bypass (group C). Outcomes were technical success, perioperative mortality, and morbidity. Survival, primary and secondary patency, and freedom from reintervention rate were estimated. Differences in ankle-brachial index (ABI), in-hospital length of stay (InH-Los), red blood cell (RBC) transfusion, and limb loss were reported. Mean follow-up was 49 (median: 35; 1-145; SD 42) months.Sixty-seven patients were included; 25 in group A, 28 in group B, and 14 in group C. PAA was symptomatic in 23 (34%) cases. Technical success was 100%. No perioperative death occurred. Three (4.5%) perioperative complications were reported with no significant difference between groups (P = 0.866). Five-years estimated survival was 78%. Estimated 5-years primary patency for groups A, B, and C was 71%, 81%, and 69%, respectively (P = 0.19). Estimated 5-years secondary patency for groups A, B, and C was 88%, 85%, and 84% (P = 0.85). Estimated 5-years freedom from reintervention for groups A, B, and C was 62%, 84%, and 70%, respectively (P = 0.16). A significant difference between preoperative ABI versus postoperative ABI was observed (P = 0.001). InH-LoS was significantly shorter in group A (P < 0.001). RBC transfusions were required significantly less in group A when compared to group C (P = 0.045). Overall limb salvage was achieved in all but 1 patient.PAA repair has good early and long-term outcomes with different treatment options. Endovascular treatment was not inferior to surgical repair with a reduced InH-LoS and RBC transfusion. It can be successfully employed even in nonelective setting. A randomized controlled trial with long-term follow-up and appropriate patient inclusion criteria is necessary to compare these 3 treatment options.

A Systematic Review and Meta-analysis of Endovascular Popliteal Aneurysm Repair Using the Hemobahn/Viabahn Stent-Graft

Purpose: To perform an evidence synthesis study to assess outcomes of endovascular repair of popliteal artery aneurysms (PAAs) using the Hemobahn or Viabahn stent-graft. Methods: A systematic literature review was conducted conforming to established standards to identify articles published between 1996 (the date of introduction of the Hemobahn stent-graft) and 2013 reporting stent-graft repair of PAAs in at least 10 patients. The data were pooled for Kaplan-Meier analysis of primary and secondary patency rates [presented with 95% confidence intervals (CIs)] as the primary outcomes. Random effects meta-analysis was performed for secondary outcomes that included rates of reintervention, endoleak, stent-graft fracture, and limb salvage. Results: Fourteen studies reported outcomes for 514 PAAs. There was considerable heterogeneity in reporting standards among studies. Pooled primary and secondary patency rates were 69.4% (95% CI 63.3% to 76.2%) and 77.4% (95% CI 70.1% to 85.3%), respectively, at 5 years. Five studies (including only one randomized controlled trial) compared surgical to endovascular repair; no difference was found in primary patency on evidence synthesis (hazard ratio 1.30, 95% CI 0.79 to 12.14, p=0.189). Conclusion: Stent-graft repair provides a feasible treatment option for anatomically suitable PAAs. Further studies are required to optimize both patient selection and follow-up protocols.

Mid-term outcomes of self-expanding covered stent grafts for repair of popliteal artery aneurysms

BACKGROUND

Enthusiasm for endovascular therapies has led to the use of stent graft repairs for popliteal artery aneurysms. In this report, we review our experience with this technique.

METHODS

A retrospective review was performed of all endovascular popliteal artery aneurysm repairs (EVPARs) performed by the vascular surgery group at a tertiary care medical center. Patient demographic data, operative details, and outcomes were examined.

RESULTS

We performed 33 EVPARs in 28 patients. All patients were male with a mean age of 76 years (range, 60-91). Mean aneurysm diameter was 3.2 cm (range, 1.5-6.3). All repairs were performed using a self-expanding covered stent graft. Among the patients, 18% were symptomatic at the time of repair. The median number of stents used was 2 (range, 1-4). Median duration of stay was 1 day (range, 0-12). The 1-year and 2-year patency were 87% and 81%, respectively, with a mean follow-up of 23 months. Loss of patency was associated with both poor distal runoff (P = .007) and increasing number of stents used (P = .03). Early complications were seen in 4 patients including: stent oversizing leading to in-folding, perforation of a tibial artery, access site hematoma, and access vessel dissection.

CONCLUSION

As experience with EVPAR continues to grow, caution must be applied in its use. Careful patient selection, proper operative technique, and correct vessel sizing are required for good outcomes. Poor distal runoff and use of numerous stents leads to diminished patency rates.

Long-term results of open repair of popliteal artery aneurysm

INTRODUCTION

Popliteal artery aneurysms (PAA) are rare. Different surgical techniques for open surgical repair are possible. This study presents a single centre experience using open surgical repair with a medial approach (MA) and outlines differences between symptomatic (SLS) and asymptomatic (ALS) legs.

METHODS

Data collection was performed retrospectively. The investigation period was from 1 January 1996 to 1 January 2013. Patients presented in the Outpatient Department and received a questionnaire concerning their quality of life. Data are presented as mean ± standard deviation. Mann-Whitney test and Cochran-Armitage test for trend was used for data analysis. Kaplan-Meier method was used to calculate limb salvage rates. p < 0.05 was considered statistically significant.

RESULTS

We analyzed 16 ALS and 26 SLS with an average age of 63.5 ± 10 years. Preoperative ankle-brachial index (ABI) was 1.0 ± 0.2 for ALS (on control examination: 1.12 ± 0.24) and 0.08 ± 0.18 for SLS (on control examination 0.94 ± 0.14) (p < 0.05). Limb salvage rate was 100% for ALS and 86.7% for SLS (overall 93.3%). Primary patency rate for SLS was 85%, for ALS rate of 100%, respectively (overall 92.5%). ALS reached an average of 13.1 ± 2.7 points (SLS 11.4 ± 2.8) on a numeric point scale.

CONCLUSION

Open surgery is therapy and prevention of acute ischaemia all in one, especially for asymptomatic patients and delivers good long-term results. Endovascular therapies offer an alternative but long-term results are pending. Open surgery should still be considered as a gold standard therapy.

Endovascular versus open repair of asymptomatic popliteal artery aneurysm

BACKGROUND

Popliteal artery aneurysm (PAA) is a focal dilatation and weakening of the popliteal artery. If left untreated, the aneurysm may thrombose, rupture or the clot within the aneurysm may embolise causing severe morbidity. PAA may be treated surgically by performing a bypass from the arterial segment proximal to the aneurysm to the arterial segment below the aneurysm, which excludes the aneurysm from the circulation. It may also be treated by a stent graft that is inserted percutaneously or through a small cut in the groin. The success of the procedure is gauged by the ability of the graft to stay patent over an extended duration. While surgical treatment is usually preferred in an emergency, the evidence on first line treatment in a non-emergency setting is unclear.

OBJECTIVES

To assess the effectiveness of an endovascular stent graft versus conventional open surgery for the treatment of asymptomatic popliteal artery aneurysms (PAA) on primary and assisted patency rates, hospital stay, length of the procedure and local complications.

SEARCH METHODS

The Cochrane Peripheral Vascular Diseases Group Trials Search Co-ordinator searched their Specialised Register (last searched June 2014) and CENTRAL (2014, Issue 5). Clinical trials databases were searched for any ongoing or unpublished studies.

SELECTION CRITERIA

All randomised controlled trials (RCTs) comparing endovascular stent grafting versus conventional open surgical repair in patients undergoing unilateral or bilateral prophylactic repair of asymptomatic PAAs were included.

DATA COLLECTION AND ANALYSIS

Data were collected on primary and secondary patency rates (primary endpoints) as well as operating time, the length of hospital stay, limb salvage and local wound complications (secondary endpoints).

MAIN RESULTS

A single RCT was identified that conformed to the inclusion criteria. There was a low risk of selection bias and detection bias. However, the risks of performance bias, attrition bias and reporting bias were unclear from the study. Despite being an RCT, the level of evidence was downgraded to moderate due to the small sample size, resulting in wide confidence intervals (CIs); only 30 PAAs were randomised over a period of five years (15 PAAs each in the groups receiving endovascular stent graft and undergoing conventional open surgery). The primary patency rate at one year was 100% in the surgery group and 93.3% in the endovascular group (P = 0.49). However, the assisted patency rate at one year was similar in both groups (100% patency). There was no clear evidence of a difference between the two groups in the primary or secondary patency rates at four years (13 grafts were patent from 15 PAA treatments in each group). However, the effects were imprecise and compatible with the benefit of either endovascular stent graft or surgery or no difference. Mean hospital stay was shorter in the endovascular group (4.3 days for the endovascular group versus 7.7 days for the surgical group; mean difference (MD) -3.40 days, 95% CI -4.42 to -2.38; P < 0.001). Mean operating time was also reduced in the endovascular group (75.4 minutes in the endovascular group versus 195.3 minutes in the surgical group; MD -119.20 minutes, 95% CI -137.71 to -102.09; P < 0.001). Limb salvage was 100% in both groups. Data on local wound complications were not published in the trial report.

AUTHORS' CONCLUSIONS

Due to the limitations of the current evidence from one small underpowered study, we are unable to determine the effectiveness of endovascular stent graft versus conventional open surgery for the treatment of asymptomatic PAAs. A larger ongoing multicentre RCT should provide more information in the future. However, it seems reasonable to suggest that endovascular repair should be considered as a viable alternative to open repair of PAA on a case by case basis.

Endovascular treatment of aneurysm of splenic artery arising from splenomesentric trunk using stent graft

We report a rare case of aneurysm of splenic artery arising anomalously from the superior mesenteric artery (SMA). The aneurysm was treated successfully by coil embolization of the splenic artery distal to aneurysm and then deploying a stent graft in the SMA. A combination of stent graft and coil embolization for the treatment of aberrant splenic artery aneurysm has been reported only once. We describe the imaging findings and the endovascular procedure in this patient.

Hygroma following endovascular femoral aneurysm exclusion: A case report

INTRODUCTION

Endovascular treatment of aneurysms in the superficial femoral artery (SFA) and popliteal segments is a suggested alternative to open surgical repair. Careful selection of patients for endovascular treatment of SFA aneurysms is mandatory.

PRESENTATION OF CASE

A complication due to endovascular stent-graft treatment in an 80-year old male with a 6 cm aneurysm in the SFA is presented. Hygroma developed after a partially unintended extravascular placed stent-graft. Two consecutive explorations resulted in a femoro-popliteal Polytetrafluoro-ethylene (PTFE) by-pass graft as the final solution.

DISCUSSION

Several explanations for the patient's complications are suggested.

CONCLUSION

A primary femoral-femoral/popliteal by-pass might be the best solution in SFA aneurysms due to risk of stent complications.

A review of surgically treated patients with obstruction after stenting in the femoropopliteal artery region

In this study, we retrospectively reviewed 36 cases that required surgical treatment in the femoropopliteal regions (46 regions) because of the development of obstructions after stent placement in these patients. Of the 46, stents were placed in 37 involved regions (80.4%) that included the common femoral and popliteal arteries; such as the common femoral, entire length of superficial femoral, or popliteal arteries, and the anastomosis site created during femoropopliteal (prosthetic graft) bypass surgeries (Group A). In contrast, 9 involved regions (19.6%) did not include the common femoral or popliteal arteries; the stents were primarily localized in the superficial femoral artery (Group B). Symptoms of stent occlusion were more severe in the former group of patients, who subsequently required peripheral artery bypass surgery. These results indicate that placement of stents in the common femoral artery and popliteal arteries should be avoided. (English translation of J Jpn Coll Angiol 2012; 52: 19-23).

Results of elective and emergency endovascular repairs of popliteal artery aneurysms

OBJECTIVE

Endovascular repair has emerged as a treatment option for popliteal artery aneurysms. Our goal was to analyze outcomes of elective and emergency endovascular popliteal artery aneurysm repair (EVPAR).

METHODS

This was a retrospective review of clinical data of patients treated with EVPAR at our institution between 2004 and 2010. Stent-related complications, patency, outcome limb salvage, and survival were evaluated and analyzed.

RESULTS

EVPAR was performed in 31 limbs of 25 patients (mean age, 81 years; range, 65-89 years). Repair was elective in 19 limbs (61%) and emergent in 12 (39%). One aneurysm ruptured and 11 presented with acute thrombosis. All 11 underwent thrombolysis before EVPAR. Patients were implanted with a mean of 2.1 Viabahn stent grafts (range, 1-4). Ten procedures (32%) were performed percutaneously and 21 by femoral cutdown. Technical success was 97%. Overall 30-day mortality was 6.4%, with 0% in the elective group, and 16.7% in the emergent group (P = .14). Early complications included graft thrombosis in two limbs (6.4%) and hematoma in four (13%), all after percutaneous repair. Myocardial infarction and thrombolysis-associated intracranial hemorrhage occurred in one patient each (3.2%). The 30-day primary and secondary patencies were 93.6% and 96.7%, respectively, and were 100% in the elective group and 83.3% and 91.6%, respectively, for the emergent group. Mean follow-up was 21.3 months (range, 1-75 months). Primary patency at 1 year was 86% (95% for elective, 69% for emergent; P = .56), secondary patency at the same time was 91% (elective, 100%; emergent, 91%). One-year limb salvage was 97%. Two-year survival was 91% for the elective group and 73% for the emergent group (P = .15). Five stent occlusions were encountered after 30 days, four in the elective group. Four underwent successful reintervention, two had bypass, and two had thrombolysis, followed by angioplasty. The fifth patient was asymptomatic and nonambulatory and remains under observation. Stent graft infolding occurred in one limb (3.2%), with no clinical sequelae. No stent migration or separation was observed. One stent fracture was noted in an asymptomatic patient. Three (10%) type II endoleaks were detected but none had aneurysm expansion. One (3.2%) type I endoleak was treated percutaneously with placement of an additional stent graft. Overall, major adverse events, including death, graft occlusion with or without reoperation, or reoperation for endoleak or stent infolding occurred after 11 procedures (35.5%). On univariate analysis, no factors predicted stent failure, including runoff, antiplatelet therapy, emergency repair, number of stents implanted, heparin bonding of the stent, or degree of stent oversizing.

CONCLUSIONS

These results support elective EVPAR in anatomically suitable patients with increased risk for open repair; however, major adverse events after EVPAR, mainly after emergency repairs, are frequent. A prospective randomized multicenter study to justify EVPAR in the emergent setting is warranted.

Complete Rupture of Polytetrafluoroethylene-covered Endoprosthesis after Exclusion of a Popliteal Aneurysm

Popliteal artery aneurysm (PAA) is the most commonly reported peripheral artery aneurysm. The usual treatment is exclusion bypass with a saphenous vein. However, the availability of medium size covered stent graft is an attractive option. By performing this procedure percutaneously, we can shorten the hospital stay of the patient. Favourable early and long-term results have been reported; however, little is known about the durability of the procedure. Given the mobile location of the stent-graft close to the knee joint, graft damage can be expected. We describe a case of complete rupture of a Viabahn(®) endoprosthesis which was inserted to exclude a PAA.