Textile Aging Characterization on New Generations of Explanted Commercial Endoprostheses: A Preliminary Study.

OBJECTIVE/BACKGROUND: The goal of the present study was to assess the aging phenomena on second-generation textile endoprostheses (EPs) through explant analysis and to establish a preliminary classification of observed defects and material damages. METHODS: From January 2011 to June 2016 110 second- and recent-generation EPs were collected as a part of a European collaborative retrieval program. The analysis focused on the first 41 consecutive commercial EPs collected between 2011 and 2014 and made from polyethylene terephthalate. Explants were submitted to a standardized evaluation protocol, which included data recording, eye-naked evaluation, cleaning of organic remnants, and structural analysis under numerical optical microscopy. Observations were reported using a classification based on 15 features evaluating the fabric, the stitches between the fabric and the stents, and the stents. The total surface area of the holes within the fabric was measured. RESULTS: EPs were implanted for thoracic and abdominal procedures in 12 and 29 cases, respectively. The mean ± SD duration of implantation was 34 ± 26 months (range 2 days-8 years). Sixty-four percent of the samples demonstrated at least one defect caused by compression damage potentially related to the insertion of the EP within the delivery system, which promoted holes and tears. Ninety-five percent of all EPs demonstrated at least one type of abrasion on the stitches. The degradation of the stitches and the number of ruptures increased with duration of implantation. Stent degradation was rare and consisted of corrosion and rupture. Cumulated holed surface area increased with time and was measured up to 13.5 mm2. CONCLUSION: Various aging-related phenomena on commercial textile EPs were identified and classified. Main damaging mechanisms were related to compression and abrasion leading to tears and holes in the fabric and rupture of stitches.

[Pre- and postoperative imaging of type B aortic dissection]. / Imagerie de la dissection aortique de type B : ce que veut savoir le chirurgien avant et après l'intervention.

Type B aortic dissections are serious diseases with a 60 to 80 % 5-year survival rate. Although typically managed with a medical treatment, surgery may be necessary in the acute/subacute or the chronic phase if significant complications are encountered. For these patients, CT angiography is the first-line imaging modality, used for indicating and preparing the surgical procedure as well as for follow-up. Physicians in charge of these patients should be familiar with the key reading points. Visceral malperfusion is the most common acute complication, while aneurysmal dilatation of the false lumen is the most common chronic complication, with surgical management generally indicated when the axial diameter of the aorta exceeds 55mm. Endovascular treatment tends to replace open surgery: it requires precise measurements and identification of the entry tear (contribution of 4D-MRA).

Five Year Outcomes of Surgical Treatment for Popliteal Artery Entrapment Syndrome.

OBJECTIVE/BACKGROUND: The aim of this study was to evaluate long-term outcomes following surgery for popliteal artery entrapment syndrome. METHODS: A retrospective study of all patients that underwent surgery for popliteal artery entrapment syndrome between January 2003 and December 2009 was performed. Patient demographic data, clinical features, imaging modalities, and surgical management were recorded. The primary outcome was 5 year patency. RESULTS: Eighteen patients (25 limbs) underwent surgery. The mean age at the time of surgical procedure was 35 (median 35 years; range 15-49). Presentation was bilateral in seven patients (39%). Diagnosis was made using various imaging modalities, including position stress test, Duplex ultrasonography, computed tomography angiography, magnetic resonance imaging and conventional angiography. In four limbs the popliteal artery was compressed and undamaged (16%), and treatment consisted of musculo-tendinous division alone. In 16 limbs the popliteal artery was damaged with lesions limited to the popliteal artery (64%) where treatment consisted of venous interposition. In five limbs lesions extended beyond the popliteal artery (20%) and procedures included one below knee femoro-popliteal bypass, three femoro-posterior tibial bypasses, and one popliteo-posterior tibial bypass. Musculo-tendinous division was associated with vascular reconstruction in 19 limbs (90%). Mean follow up was 82 months (median 81 months, range 60-120). Five year patency was 84%. CONCLUSION: Long-term outcomes of surgical procedures performed for popliteal artery entrapment syndrome can be considered satisfactory.

[Contribution of mathematical models and biomechanical properties in predicting the risk of abdominal aortic aneurysm rupture]. / Apport des modèles mathématiques et des études biomécaniques dans la prédiction du risque de rupture des anévrysmes de l'aorte abdominale.

INTRODUCTION: Rupture is the worst outcome of abdominal aortic aneurysm (AAA). The decision to operate should include counterbalancing the risk of aneurysm rupture against the risk of aneurysm repair, within the context of a patient's overall life expectancy. Current surgical guidelines are based on population studies, and important variables are missed in predicting individual risk of rupture. METHODS: In this literature review, we focused on the contribution of biomechanical and mathematical models in predicting risk of AAA rupture. RESULTS: Anatomical features as diameter asymmetry and lack of tortuosity are shown to be anatomical risk factors of rupture. Wall stiffness (due to modifications of elastin and collagen composition) and increased inflammatory response are also factors that affect the structural integrity of the AAA wall. Biomechanical studies showed that wall strength is lower in ruptured than non-ruptured AAA. Intra-luminal thrombus also has a big role to play in the occurrence of rupture. Current mathematical models allow more variables to be included in predicting individual risk of rupture. CONCLUSION: Moving away from using maximal transverse diameter of the AAA as a unique predictive factor and instead including biological, structural and biomechanical variables in predicting individual risk of rupture will be essential in the future and will help gain precision and accuracy in surgical indications.

Results of isolated infrapopliteal percutaneous transluminal angioplasty for critical limb ischemia in high-risk diabetic patients.

AIM: Infrapopliteal occlusive arterial lesions mostly characterize diabetic patients arteriopathy. Diabetic patients are prone to multiple comorbidities that make them candidates for low-invasive therapeutic options. The aim of this study was to evaluate the safety of infrapopliteal angioplasty in high-risk diabetic patients. METHODS: We undertook a study (retrospective study of a prospectively collected database) of all infrapopliteal endovascular revascularizations performed for critical limb ischemia in high-risk (≥3 major comorbidities) diabetic patients in our institution between 2008 and 2010. Study end points were safety, technical success rate, healing rate, overall 1-year survival, primary patency, secondary patency and limb salvage rates. RESULTS: A total of 101 high-risk diabetic patients (160 arterial lesions: 94 stenosis and 66 occlusions) underwent infrapopliteal endovascular surgery. No major adverse cardiovascular or cerebrovascular event was recorded within 30 days. Two major adverse limb events (two thromboses requiring major amputation) and seven minor adverse events were recorded. Technical and healing rates were, respectively, 83% and 78%. The 1-year survival, primary patency, secondary patency and limb salvage rates were, respectively, 86%, 67%, 83% and 84%. CONCLUSION: Infrapopliteal angioplasty can be considered as a safe and feasible option for high-risk diabetic patients with critical limb ischemia.

Gender related Long-term Differences after Open Infrainguinal Surgery for Critical Limb Ischemia.

OBJECTIVE: The role of gender on long-term infrainguinal open surgery outcomes still remains uncertain in critical limb ischemia patients. The aim of this study is to evaluate the gender-specific differences in patient characteristics and long-term clinical outcomes in terms of survival, primary patency and limb salvage among patients undergoing infrainguinal open surgery for CLI. MATERIAL AND METHODS: All consecutive patients undergoing infrainguinal open surgery for critical limb ischemia between 2003 and 2012 were included. Survival, limb salvage and primary patency rates were assessed. Independent outcome determinants were identified by the Cox proportional hazard ratio using age and gender as adjustment factors. RESULTS: 584 patients (269 women and 315 men, mean age 76 and 71 years respectively) underwent 658 infrainguinal open surgery (313 in women and 345 in men). Survival rate at 6 years was lower among women compared to men with 53.5% vs 70.9% (p < 0.001). The same applied to primary patency (35.9% vs 52.4%, p < 0.001) and limb salvage (54.3% vs 81.1%, p < 0.001) at 6 years. Female-gender was an independent factor predicting death (hazard ratio 1.50), thrombosis (hazard ratio 2.37) and limb loss (hazard ratio 7.05) in age and gender-adjusted analysis. CONCLUSION: Gender-related disparity in critical limb ischemia open surgical revascularization outcomes still remains.

Chronic mesenteric ischemia: 20 year experience of open surgical treatment.

OBJECTIVES: Both open surgery (OS) and endovascular surgery (ES) have been proposed for the treatment of symptomatic chronic mesenteric ischaemia (CMI). OS was considered the gold standard but ES is increasingly proposed as the first option. The aim was to report long-term outcomes associated with OS in patients suffering CMI in the modern era in order to help in choose between the two techniques. MATERIALS AND METHODS: A retrospective single centre analysis of all consecutive digestive artery revascularizations performed for CMI between January 2003 and December 2012 was carried out. Primary outcomes were 30 day mortality and morbidity, and secondary outcomes were survival, primary patency (PP), secondary patency (SP), and freedom from digestive symptoms, depending on the completeness of the revascularization performed. RESULTS: Eighty-six revascularizations were performed. Median follow up was 6.9 years (range 0.3-20.0). The 30 day mortality and morbidity rates were respectively 3.5% and 13.9%. Ten year survival was 88% for complete revascularization (CR) and 76% for incomplete revascularization (IR) (p = .54). The PP was 84% at 10 years for CR and 87% respectively for IR (p = .51). The 10 year SP was 92% for CR and 93% for IR (p = .63). Freedom from digestive symptoms was influenced by the completeness of revascularization: 79% for CR versus 65% for IR at 10 years (p = .04). CONCLUSIONS: OS for CMI, especially complete revascularization, provides lasting results despite high morbidity.

Current optimal morphological evaluation of peripheral arterial diseases.

Imaging plays a central role in the management of peripheral arterial diseases (PAD), emphasized by the continuously increasing use of modern cross-sectional imaging and the corresponding decline of digital subtraction angiography (DSA) in the diagnostic setting. Imaging is sometimes used as a screening tool in high-risk individuals. In symptomatic patients, imaging is mandatory to make an accurate positive diagnosis, grade the severity and the extent of the abnormalities, carefully choose and plan the best therapeutic option and provide adequate follow-up. Non-invasive diagnosis of PAD can be made by Doppler ultrasonography, magnetic resonance angiography (MRA) and computed tomography angiography (CTA). Given the major technological breakouts over the last decade, MRA and especially CTA are nowadays mature and precise enough to properly answer all the questions raised in symptomatic patients. This review article aims at describing state-of-the-art non-invasive imaging of PAD, its involvement in the decision-making for the vascular surgeon and the future trends and developments expected in the coming years.

Popliteal artery entrapment syndrome.

Intermittent claudication is frequently encountered in vascular surgical practice in atherosclerotic patients. However, it may also be observed in a younger subset of patients without any cardiovascular risk factors and can represent a challenging diagnosis. Popliteal artery entrapment syndrome is rare but can cause intermittent claudication in young people. There is a lack of consensus about optimal strategies or diagnosis and management, particularly for variants such as functional popliteal entrapment. Since the first description in 1959, knowledge of the pathology and the underlying anatomic abnormalities was advanced through sporadic publications of case reports and small case series, but popliteal artery entrapment syndrome still remains a rare anatomic abnormality. It can be difficult to differentiate from other causes of lower limb pain in young patients, and diagnosis can be challenging. We propose to review clinical symptomatology, classification, radiological diagnosis and treatment of popliteal entrapment syndrome.

Poor long-term stability of the Corvita abdominal stentgraft.

INTRODUCTION: The endovascular treatment of abdominal aortic aneurysms was introduced in the early 1990s, with different generations of devices using various options for either the stent skeleton or the membrane. REPORT: Corvita generated one of these devices using braided stainless steel and a porous spun polycarbonate urethane membrane. DISCUSSION: In this report, we describe a case involving Corvita stentgraft explantation for complete aneurysm reperfusion after 13 years, demonstrating major degradation of the polyurethane membrane.

Practical experience with the TAG and conformable TAG devices: lessons learned in about 100 cases.

AIM: We reported our 10-year experience with the Gore TAG thoracic endoprosthesis for treatment of thoracic aorta pathologies. METHODS: We performed a systematic retrospective study of prospectively recorded data of all patients who underwent thoracic endovascular aortic repair (TEVAR) procedure with Gore TAG thoracic endoprosthesis between January 2001 and March 2013, and conducted an analysis of patient demographics, periprocedural records, complications, reinterventions, and survival. RESULTS: During this period, 96 patients underwent TEVAR with Gore TAG device. Indications for operation were degenerative aneurysm in 38 patients (39.6%), type B aortic dissection in 24 (25.0%), penetrating ulcer in 8 (8.3%), intramural hematoma in 10 (10.4%), traumatic transection in 9 (9.4%), and other pathology in 7 (7.3%). Forty-four patients (45.8%) had acute thoracic aortic syndromes requiring immediate or delayed procedures. Forty-two (43.8%) patients underwent supra-aortic trunks debranching. Landing zones were zone 0 in 8 patients (8.3%), zone 1 in 4 (4.2%), zone 2 in 36 (37.5%), zone 3 in 29 (30.2%) and zone 4 in 19 (19.8%). Technical success rate was 96.6%. Thirty-day mortality was 10.4%. Major adverse events included stroke in 8.3%, spinal cord ischemia in 4.2%, and vascular injuries in 7.3%. Overall survival in the cohort was 86% at 1 year and 78% at 2 years with a mean follow-up of 11.1±12.4 months. Major reintervention was required in 10 patients (10.4%). CONCLUSION: This single-center study demonstrates acceptable rates for operative mortality and major adverse events after endovascular repair of various thoracic aortic pathologies with both generations of Gore TAG device. However, a better knowledge in long-term results is necessary to define target populations.

Properties and challenges in materials used as vascular and endovascular devices.

In the last decades, main evolutions in the field of vascular surgery have been correlated to the development of devices allowing more reliable and safe sustainable treatment. First devices that have been proposed were vascular prostheses made of polymeric materials. The second generation of devices was stents made of metals and alloys. The third generation, endografts, associated these both materials. Materials used as vascular and endovascular devices must meet a number of requirements based on dimensional, physical and mechanical criteria. Ideally, they should demonstrate a behavior as close as possible as that of human arteries in terms of mechanical properties such as compliance, long-term durability, and in terms of biological properties such as biocompatibility, luminal surface healing and thrombogenicity. We propose in the present manuscript a review of properties of materials currently used for the construction of vascular and endovascular devices, future challenges in the fields of new materials and scientific approaches and tests to understand and predict the behavior of the next generations of devices.