Waligraft endoprosthesis for the percutaneous treatment of femoral and popliteal artery aneurysms

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.

Update on the Diagnosis and Management of Popliteal Aneurysm and Literature Review

Popliteal artery aneurysms (PAAs) are the most frequent peripheral aneurysm with a significant morbidity if left untreated. Open surgical technique is still considered the gold standard; however the revolution in endovascular repair has proven to be a valid alternative option in selected patients. The role of endovascular treatment in PAA is still considered in its infancy. In addition, the indications for use of endovascular stents as compared to standard open surgery have not yet been fully defined and more studies are warranted to characterize the durability of this technique. This article describes the general principles of the natural history, clinical presentation, and long-term limb salvage and survival outcomes for patients with such aneurysms. It also details the features and results for the devices in current use and highlights the current consensus in the management of PAA.

Stent graft exclusion of a pseudoaneurysm in a Blalock-Taussig shunt

This case is the first report of slow-growing pseudoaneurysm after vessel dissection secondary to two stents implantation into classic Blalock Taussig shunt in a patient with pulmonary atresia and ventricular septal defect. Pseudoaneurysm was successfully excluded by a percutaneous approach with self-expandable stent graft deployment from the aorta to the middle of the Blalock Taussig shunt. Nearly 3 years after the procedure, the classic BT is patent, and there were no restenosis or thrombosis in spite of the very long length of the stented segment.

Tratamento endovascular de aneurisma de artéria poplítea

CONTEXTO: Dos aneurismas periféricos, o da artéria poplítea é o mais freqüente, correspondendo a 70 a 80% dos casos. O tratamento cirúrgico convencional consta de exclusão do aneurisma e interposição de enxerto em ponte ou de ressecção parcial ou total do aneurisma e reconstrução arterial com enxerto em continuidade. O tratamento endovascular surgiu como uma alternativa ao reparo convencional. OBJETIVO: Avaliar o uso de endoprótese para o tratamento endovascular do aneurisma de artéria poplítea. METODOLOGIA: Num total de 17 pacientes, todos do sexo masculino, 11 foram tratados por técnica endovascular, utilizando-se próteses Hemobahn e Viabahn. RESULTADOS: Um paciente apresentou pseudo-aneurisma no pós-operatório imediato. Dentre as complicações tardias, um paciente apresentou endoleak distal da prótese após 7 meses, e houve oclusão da endoprótese em outro. Os nove pacientes restantes apresentaram controle de eco-Doppler satisfatório aos 20 meses, resultando em uma perviedade primária de 90% em um período médio de 27 meses de seguimento. CONCLUSÃO: O tratamento endovascular para aneurisma de artéria poplítea é factível e apresenta algumas vantagens em relação ao tratamento aberto, como menor tempo de internação e de recuperação.

Alternativa técnica no tratamento endovascular dos aneurismas da artéria poplítea

O aneurisma de artéria poplítea é relativamente raro, porém representa cerca de 85% de todos os aneurismas arteriais periféricos. Apresenta-se geralmente com um quadro de complicação isquêmica e elevado risco de perda do membro acometido. Em função disso, preconiza-se seu tratamento eletivo, atualmente realizado com resultados satisfatórios pela técnica endovascular. Relatamos nossa experiência com a utilização do stent de nitinol auto-expansível revestido com PTFEe - Fluency (Bard, Alemanha), reforçado internamente com o stent de nitinol auto-expansível Zilver (Cook, EUA) no tratamento de um aneurisma de artéria poplítea.

Early complications and long-term outcome after open surgical treatment of popliteal artery aneurysms: is exclusion with saphenous vein bypass still the gold standard?

BACKGROUND

Popliteal artery aneurysms (PAAs) are rare, but thromboembolic complications may result in limb loss. To define complications and outcomes after open surgical repairs, we reviewed our experience.

METHODS

Clinical data of patients with PAA seen between 1985 and 2004 at Mayo Clinic, Rochester, Minnesota, were reviewed and outcomes in 289 patients with open revascularization were analyzed. Kaplan-Meier method with log-rank tests, chi(2), and Wilcoxon rank sum tests were used for analysis.

RESULTS

A total of 358 PAAs were treated in 289 patients, consisting of 281 (97%) men and eight (3%) women. There were 133 (46%) unilateral and 156 (54%) bilateral PAAs with a mean diameter of 2.9 cm (range, 1.5 to 9 cm). Abdominal aortic aneurysm (AAA) was more frequent with bilateral than unilateral PAAs (65% [101/156] vs 42% [56/133] P = .001). There were 144 (40%) asymptomatic limbs (group 1), 140 (39%) had chronic symptoms (group 2), and 74 (21%) had acute ischemia (group 3). Great saphenous vein (GSV) was used in 242 limbs (68%), polytetrafluoroethylene (PTFE) in 94 (26%), and other types of graft in 22 (6%). Early mortality was 1% (3/358), all in group 3 (4% [3/74]). Six of seven patients with perioperative myocardial infarctions belonged to group 3 (8%). The 30-day graft thrombosis rate was 4%, with 1% in group 1 (1/144), 4% in group 2 (5/140), and 9% in group 3 (7/74). All six early amputations (8%) were in group 3, five with failed bypass (4 PTFE, 1 GSV). Mean follow-up was 4.2 years (range, 1 month to 20.7 years). The 5-year primary and secondary patency rates were 76% and 87%, respectively, higher with GSVs (85% and 94%) than PTFE (50% and 63%, P < .05). Seven recurrent PAAs (2%) required reintervention. The 5-year freedom from reintervention was 100% after endoaneurysmorrhaphy vs 97% after ligations (P = .03). Five-year limb salvage rate was 97% (85% in group 3). There was no limb loss in group 1 and none in group 2 with GSV. In group 3, preoperative thrombolysis reduced the amputation rate in class II patients with marginally threatened limbs (96% vs 69%, P = .02).

CONCLUSION

Acute presentation of PAA continues to carry high mortality and cardiac morbidity; although preoperative thrombolysis appears to improve results, the 8% early and 15% late amputation rates remain ominous. Early elective repair is recommended because these patients had no surgical mortality, a low rate of complications, and asymptomatic patients had no limb loss at 5 years. GSV and endoaneurysmorrhaphy continues to be the gold standard for open repair of PAA.

A Contemporary Review of Popliteal Artery Aneurysms

Popliteal artery aneurysms account for 85% of all peripheral aneurysms and are frequently associated with abdominal aortic aneurysms. Up to 75% of all popliteal artery aneurysms are discovered in symptomatic patients who present with arterial insufficiency, leg swelling, or pain. Popliteal artery aneurysms can be diagnosed with duplex ultrasonography. Aneurysm repair should be considered for all symptomatic patients with rest pain or limb-threatening symptoms. Asymptomatic aneurysms larger than 2 cm should also be treated to prevent the development of limb-threatening ischemia and assure better surgical bypass graft patency and longer freedom from amputation. Conventional aneurysm repair consists of either opening the aneurysm sac and interposing a bypass graft or aneurysm ligation combined with bypass grafting. If the aneurysm sac is left intact, side branch perfusion may persist and the aneurysm may continue to enlarge and can rupture. Endovascular popliteal aneurysm repair has not demonstrated clinical equipoise to standard surgery but may be advantageous in select high-risk patients.

Mid-term outcomes of endovascular popliteal artery aneurysm repair

OBJECTIVE

This study documents mid-term outcomes of a series of endovascular popliteal aneurysm repairs compared with concurrent results of open surgical repair.

METHODS

A retrospective chart review was done of all popliteal artery aneurysm repairs since January 1, 2000. Patency was defined as continued presence of palpable pulses or maintenance of postoperative ankle-brachial index +/- 0.15. Statistical methods included chi(2), t test, Fisher's exact test, and Kaplan-Meier plots with log-rank comparison.

RESULTS

A total of 56 popliteal artery aneurysm repairs were performed. All endovascular popliteal aneurysm repairs (EVPAR, n = 15) were performed using Viabahn endoprostheses. Patients with open repair (OR, n = 41) underwent surgical bypass and aneurysm exclusion with great saphenous vein (n = 26), short saphenous vein (n = 3), or polytetrafluoroethylene (n = 12), through either a medial (n = 28) or posterior (n = 13) approach. All urgent cases received open repair. Technical success was 100% in both groups. Mean follow-up was 16.5 +/- 3 months (range, 0.5 to 56 months). Aneurysm size, location, and outflow were similar between groups. Primary patency, secondary patency, and survival did not differ between groups. Endoleaks were observed in three (20%) of 15 endovascular cases, and type I and III endoleaks were treated with additional endografts.

CONCLUSION

To our knowledge, this represents the largest United States series of EVPAR to date. Early mid-term results of elective endovascular repair of popliteal artery aneurysms are encouraging. Further studies are warranted to define optimal indications for EVPAR and to generate long-term outcomes for this technique.

The posterior approach for repair of popliteal artery aneurysms

OBJECTIVES

Ligation and bypass is the most commonly performed surgical treatment for popliteal artery aneurysm. This approach can be complicated by persistent collateral flow to the excluded aneurysm sac, which may lead to aneurysm growth, the development of compressive symptoms, and in some cases, rupture. Repair of popliteal aneurysms by posterior endoaneurysmorrhaphy and reconstruction with a short prosthetic interposition graft avoids these complications because patent collaterals communicating with the aneurysm sac are oversewn at the time of surgery. We report the early and mid-term outcomes of popliteal artery aneurysm repair using this posterior approach.

METHODS

The records of all patients operated on for popliteal artery aneurysm from December 1981 to June 2003 were retrospectively reviewed. Patients who underwent popliteal artery aneurysm repair with a posterior approach were included in the study.

RESULTS

From 1981 to 2003, 30 popliteal aneurysms (mean diameter, 3.2 cm; range, 1.9 to 6.2 cm) were repaired in 24 patients using a posterior approach with interposition prosthetic grafting. The median follow up was 21.5 months. Primary patency, primary assisted patency, and secondary patency were 92.2%, 95.8%, and 95.8%, respectively, at 1 and 2 years. The limb salvage rate was 100%.

CONCLUSIONS

Popliteal endoaneurysmorrhaphy using a posterior approach with interposition prosthetic grafting is simple, safe, and effective. The patency and limb salvage rates are equivalent to those obtained with ligation and vein bypass. In addition, the posterior approach eliminates the postoperative complications associated with persistent collateral flow into the aneurysm sac.

Open repair versus endovascular treatment for asymptomatic popliteal artery aneurysm: Results of a prospective randomized study

PURPOSE

The aim of this prospective randomized study was to evaluate the relative risks and advantages of using the Hemobahn graft for popliteal artery aneurysm (PAA) treatment compared with open repair (OR). The primary end point was patency rate; secondary end points were hospital stay and length of surgical procedure.

METHODS

The study was a prospective, randomized clinical trial carried out at a single center from January 1999 to December 2003. Inclusion criteria were an aneurysmal lesion in the popliteal artery with a diameter > or = 2 cm at the angio-computed tomography (CT) scan, and proximal and distal neck of the aneurysm with a length of > 1 cm to offer a secure site of fixation of the stent graft. Exclusion criteria were age < 50 years old, poor distal runoff, contraindication to antiplatelet, anticoagulant, or thrombolytic therapy, and symptoms of nerve and vein compression. The enrolled patients were thereafter prospectively randomized in a 1-to-1 ratio between OR (group A) or endovascular therapy (ET) (group B). The follow-up protocol consisted of duplex ultrasound scan and ankle-brachial index (ABI) measured during a force leg flexion at 1, 3, and 6 months. Group B patients underwent an angio-CT scan and plain radiography of the knee with leg flexion (> 120 degrees) at 6 and 12 months, and then yearly.

RESULTS

Between January 1999 and December 2003, 30 PAAs were performed: 15 OR (group A) and 15 ET (group B). Bypass and exclusion of the PAA was the preferred method of OR; no perioperative graft failure was observed. Twenty stent grafts were placed in 15 PAAs. Endograft thrombosis occurred in one patient (6.7%) in the postoperative period. The mean follow-up period was 46.1 months (range, 12 to 72 months) for group A and 45.9 months (range, 12 to 65 months) for group B. Kaplan-Meier analysis showed a primary patency rate of 100% at 12 months for OR and 86.7% at 12 months with a secondary patency rate of 100% at 12 and 36 months for ET. No statistical differences were observed at the log-rank test. The mean operation time (OR, 155.3 minutes; ET, 75.4 minutes) and hospital stay (OR, 7.7 days; ET, 4.3 days) were statistically longer for OR compared with ET (P < .01).

CONCLUSION

We can conclude, with the power limitation of the study, that PAA treatment can be safely performed by using either OR or ET. ET has several advantages, such as quicker recovery and shorter hospital stay.

The value of duplex surveillance after open and endovascular popliteal aneurysm repair

OBJECTIVE

The objective of this study was to determine the clinical value of vascular laboratory surveillance after open or endovascular repair of popliteal aneurysm by analysis of the frequency and nature of secondary interventions performed.

METHODS

Over an 8-year period, 55 popliteal artery aneurysms were repaired in 46 men (mean age, 72 years) by aneurysm ligation and bypass grafting (vein, 37; prosthetic, 7), endoaneurysmorrhaphy and interposition grafting (prosthetic, 3; vein, 1), or endograft exclusion (n = 7). Indications for intervention included aneurysm thrombosis with critical limb ischemia (n = 8), symptomatic (n = 10) or asymptomatic (n = 37), >1.75 cm popliteal aneurysm with mural thrombus. Catheter-directed thrombolysis was used in three limbs to restore aneurysm and tibial artery patency before open repair. Duplex ultrasound surveillance was performed after repair to identify residual and acquired lesions. Life-table analysis was used to estimate repair site intervention-free (primary) and assisted-primary patency.

RESULTS

During a mean 20-month follow-up interval, 20 secondary procedures were performed in 18 (31%) limbs to repair duplex-detected graft stenosis (n = 10), repair site thrombosis (n = 5), vein graft aneurysm (n = 3), graft entrapment (n = 1), or type 1 endoleak (n = 1). Primary patency was 76% and 68% at 1 and 3 years, and was uninfluenced by tibial artery runoff status or type of bypass conduit. Open (n = 12) or endovascular (n = 8) secondary procedures were performed on 15 (12 vein, 3 prosthetic) bypass grafts, 2 endografts, and 1 interposition graft. Mean time to repair graft stenosis (11 months) was shorter than to repair of vein graft aneurysm (37 months). Assisted-primary patency was 93% and 88% at 1 and 3 years; redo bypass grafting was required and successful in five limbs. Limb salvage was 100%.

CONCLUSIONS

One third of popliteal artery aneurysms repaired by open or endovascular procedures required a secondary intervention within 2 years of repair. Repair-site surveillance using duplex ultrasound was able to identify lesions that threaten patency, which resulted in excellent assisted patency and limb preservation rates when corrected.

Biomechanical Incompatibility of Popliteal Stent Placement

Peripheral stents or endografts in specific arterial segments are exposed to extreme mechanical stress. Despite high rates of primary technical success, mechanical bending due to knee joint flexion can limit long-term patency of stents or endografts in the popliteal artery or the femoropopliteal segment. Every stent or endograft responds differently to bending during knee joint flexion, which can be revealed only by functional investigation. Mechanical bending has to be considered in future studies to assess the influence of differences in stent design, material, or postinterventional drug treatment on the long-term patency of endoprostheses in the femoropopliteal segment. To demonstrate the concept of biomechanical incompatibility, we present several illustrations of different stent designs placed in the popliteal artery.

Management of carotid injuries in a hostile neck using endovascular grafts

Pseudoaneurysms and iatrogenic injuries of the extracranial carotid artery are not common but represent unique operative challenges with associated high morbidity and mortality. We report two cases in which a Wallgraft was used via percutaneous femoral access to treat such injuries. In the first, a 6-cm carotid pseudoaneurysm was successfully excluded by coil embolization of the external carotid artery and stent grafting across the carotid bifurcation. In the second case, an endovascular graft was used to treat an intraoperative common carotid injury in a re-operated, radiated neck. These cases demonstrate the utility of endovascular graft treatment of emergent carotid injuries.

Fate of excluded popliteal artery aneurysms

OBJECTIVE

Popliteal artery aneurysms (PAA) are frequently treated with ligation and exclusion bypass grafting. It is assumed that these aneurysms will shrink and remain asymptomatic. This may not always be true. We sought to elucidate the fate of excluded PAA over time.

METHODS

Data for all PAAs treated with ligation and exclusion bypass grafting between 1986 and 1999 were retrospectively reviewed. Computed tomography (CT) scans and duplex ultrasound scans provided aneurysm patency data and maximal transverse diameter measurements of the popliteal artery during late postoperative follow-up. This information was compared with that from similar preoperative studies.

RESULTS

Forty-one patients (39 men, 2 women) underwent 57 ligation and exclusion bypass grafting procedures. Both preoperative and late postoperative (mean, 4.0 years; range, 0.43-13.5 years) CT scans or duplex ultrasound scans were available for review of 25 PAAs in 18 patients (ages 42-80 years; mean, 63 years). Preoperative PAA size ranged from 14 to 45 mm (mean, 28.7 mm). In late follow-up, 12 (48%) PAA had decreased in size (mean, 7.3 mm), 5 (20%) remained unchanged, and 8 (32%) increased in mean transverse diameter (mean, 5.9 mm). One large aneurysm increased by 50%. Contrast material enhancement was identified in the excluded sac in 11 aneurysms.

CONCLUSIONS

PAA treated with ligation and exclusion bypass grafting often expand and can become symptomatic. This may be analogous to type II endoleak or endotension noted after aortic endovascular repair. We recommend PAA excision or endoaneurysmorrhaphy when feasible.

Treatment of popliteal artery aneurysms with the Hemobahn stent-graft

PURPOSE

To report a prospective study to ascertain the results of popliteal aneurysm treatment with a self-expanding stent-graft.

METHODS

In a recent 3-year period, 21 patients (18 men; median age 67 years, range 52-82) with 23 popliteal aneurysms were treated with Hemobahn stent-grafts. Follow-up evaluation included duplex scanning, ankle-brachial index (ABI) measurements, and radiographic examination of the knee. Outcome measures were occlusion of the stent-graft and limb loss.

RESULTS

Technical success in placing the stent-graft and excluding the aneurysm was 100%. An additional vascular intervention was performed in the same session in 5 (24%) cases. In the other 16 patients, local anesthesia was used in 10 (63%). During a median follow-up of 15 months (range 2-37), 5 (22%) of 23 stent-grafts occluded, resulting in a cumulative patency of 74%. All occlusions occurred within 6 months after the intervention; 2 were successfully recanalized, and none of the 3 patients with persisting occlusion required an amputation.

CONCLUSIONS

The results of this study suggest that endovascular stent-graft repair of popliteal artery aneurysms is feasible. Midterm patency rates are lower compared to traditional surgical repair.

Stent-graft repair of a recurrent popliteal arteriovenous fistula

PURPOSE

To describe the successful endovascular treatment of a popliteal arteriovenous fistula with a stent-graft.

CASE REPORT

A 54-year-old man was referred to our hospital with a distal popliteal arteriovenous fistula following an arthroscopic meniscectomy 6 years earlier. Three surgical attempts to close the fistula were undertaken, but the fistula recurred. He now presented with symptoms of progressive venous hypertension with claudication, swelling of the leg, and ulceration at the ankle. The fistula was closed with a stent-graft deployed percutaneously. At 18 months, the patient is doing well; duplex evaluation has documented the patency of the popliteal artery and the stent-graft.

CONCLUSIONS

Endovascular treatment of a popliteal arteriovenous fistula is an alternative to open surgical reconstruction. In this situation, after multiple failed surgical closures and in a leg with extensive venous hypertension, it may be the best treatment option.