Jan M.M. Heyligers

In Vivo Cell Seeding With Anti-CD34 Antibodies Successfully Accelerates Endothelialization but Stimulates Intimal Hyperplasia in Porcine Arteriovenous Expanded Polytetrafluoroethylene Grafts

Background—The patency of AV expanded polytetrafluoroethylene (ePTFE) grafts for hemodialysis is impaired by intimal hyperplasia (IH) at the venous outflow tract. The absence of a functional endothelial monolayer on the prosthetic grafts is an important stimulus for IH. In the present study, we evaluated the feasibility of capturing endothelial progenitor cells in vivo using anti-CD34 antibodies on ePTFE grafts to inhibit IH in porcine AV ePTFE grafts. Methods and Results—In 11 pigs, anti-CD34–coated ePTFE grafts were implanted between the carotid artery and internal jugular vein. Bare ePTFE grafts were implanted at the contralateral side. After 3 (n=2) or 28 (n=9) days, the pigs were terminated, and the AV grafts were excised for histological analysis and SEM. At 3 and 28 days after implantation, 95% and 85% of the coated graft surface was covered by endothelial cells. In contrast, no cell coverage was observed in the bare graft at 3 days, whereas at 28 days, bare grafts were partly covered with endothelial cells (32%; P=0.04). Twenty-eight days after implantation, IH at the venous anastomosis was strongly increased in anti-CD34–coated grafts (5.96±1.9 mm2) compared with bare grafts (1.70±0.4 mm2; P=0.03). This increase in IH coincided with enhanced cellular proliferation at the venous anastomosis. Conclusions—Autoseeding with anti-CD34 antibodies results in rapid endothelialization within 72 hours. Despite persistent endothelial graft coverage, IH at the outflow tract is increased profoundly at 4 weeks after implantation. Further modifications are required to stimulate the protective effects of trapped endothelial cells.

Endovascular Aneurysm Sealing Early and Midterm Results From the EVAS FORWARD Global Registry

Purpose: To report the early and 12-month results of a global registry of patients treated with endovascular aneurysm sealing (EVAS) for abdominal aortic aneurysms (AAAs). Methods: The EVAS FORWARD Global Registry was a postmarket, multicenter, open-label, single-arm registry that enrolled 277 patients (mean age 75 years; 228 men) treated with the Nellix EVAS system for nonruptured AAAs at 18 sites over a 1-year period. The cohort had challenging aortic anatomy, with 17% having a proximal aortic neck length <10 mm, 8% a neck angulation >60°, and 20% an iliac diameter >25 mm. Baseline and follow-up computed tomography images were assessed by an independent core laboratory, and major adverse events were reviewed by an independent safety committee. Results: Three patients died within 30 days of the procedure (none device-related). There were 13 endoleaks recorded in this time frame: 8 type Ia, 1 type Ib, and 5 type II. Root cause analysis demonstrated that the majority of type Ia endoleaks were due to technical error (low device placement and underfilling of the endobags). Between 30 days and 1 year, there were 4 new type Ia endoleaks; all were treated. There was also 1 type III endoleak between a Nellix device and a distal extension limb. At 1 year, the persistent endoleak rate was 0.7% (1 type Ia and 1 type II). The Kaplan-Meier estimates of freedom from types I and II endoleak at 12-month follow-up were 96% and 98%, respectively. The estimate of freedom from open conversion (n=7) was 98% at 12 months and the rate of freedom from any reintervention was 92%. The need for secondary intervention was associated with aortic morphology; for patients meeting the requirements of the instructions for use (IFU), the freedom from reintervention at 12 months was 98% compared with 86% when the implant was outside the IFU (p=0.009). At 1 year, the estimates of freedom from aortic-related and all-cause mortality were 98% and 95%, respectively. Conclusion: The EVAS FORWARD Global Registry documents the 12-month outcome of EVAS in an unselected group of patients with challenging aortic morphology. The results at present appear acceptable with regard to perioperative outcomes and complications. The type II endoleak rate is low. The place of EVAS in the armamentarium of techniques to treat AAAs will be defined by durability data in the longer term.

Spiral Vein Reconstruction of the Infected Abdominal Aorta Using the Greater Saphenous Vein: Preliminary Results of the Tilburg Experience

OBJECTIVES The aim of this study was to evaluate patients, who underwent spiral vein reconstruction of the abdominal aorta to repair infected aneurysms or replace infected aortic grafts. METHODS All spiral vein reconstructions between March 2005 and May 2010 because of vascular infections of the abdominal aorta were retrospectively included. Diagnosis was determined by clinical examination, laboratory results, computed tomography (CT) and positron emission tomography (PET) scan, and microbiological tests. Spiral vein reconstruction consisted of harvesting the greater saphenous vein (GSV) and construction into a spiral graft, aortic reconstruction and a transmesenteric omentumplasty. Primary outcomes were survival and limb salvage. Secondary outcomes included technical, clinical and ongoing success, re-infection, ongoing infection and patency. RESULTS All five patients survived surgery, and there were no in-hospital deaths. Survival and limb salvage were 100% after median follow-up of 13 months (6-67 months). Further, technical, clinical and continuing success was 100%. There were no re-infections or ongoing infections. CONCLUSIONS Spiral vein reconstruction using the GSV showed good short-term survival and limb salvage. It, therefore, might be considered as an attractive treatment method for vascular infections of the abdominal aorta. Still, more follow-up is needed to evaluate long-term results.

A heparin-bonded vascular graft generates no systemic effect on markers of hemostasis activation or detectable heparin-induced thrombocytopenia–associated antibodies in humans

OBJECTIVES Almost a third of patients who undergo peripheral bypass procedures do not have suitable veins, making the use of prosthetic materials necessary. Prosthetic materials can cause platelet adhesion and activation of the coagulation cascade on the graft. One potential strategy to reduce this thrombogenicity is to covalently bind heparin to the endoluminal surface of grafts. This human in vivo study examined systemic effects of the endoluminal heparin and addressed whether graft implantation results in (1) a measurable reduction of systemic markers of hemostasis activation compared with control grafts and (2) antibody formation against heparin, potentially responsible for heparin-induced thrombocytopenia (HIT). METHODS The study included 20 patients undergoing femoropopliteal bypass grafting, of whom 10 received a standard Gore-Tex Thin Walled Stretch Vascular Graft (W. L. Gore & Associates, Flagstaff, Ariz) and 10 received a heparin-bonded expanded polytetrafluoroethylene (ePTFE) graft (Gore-Tex Propaten Vascular Graft). Blood samples were drawn before and directly after the operation and at days 1, 3, 5, and week 6 after surgery. Established markers of in vivo activation of platelets and blood coagulation (prothrombin fragment 1+2, fibrinopeptide A, soluble glycoprotein V, thrombin-antithrombin complexes, and D-dimers) were measured using standard commercially available techniques. Antiplatelet factor 4/heparin antibody titers were measured using a commercially available enzyme-linked immunosorbent assay, and platelet counts were determined. RESULTS No statistical differences were observed in any of the markers of in vivo activation of platelets and blood coagulation between patients receiving Propaten or control ePTFE. Moreover, no antibodies against heparin could be demonstrated up to 6 weeks after implantation. CONCLUSIONS No measurable effect of heparin immobilization on systemic markers of hemostasis was found using a heparin-bonded ePTFE graft in vivo. Also, no antibodies against heparin could be detected up to 6 weeks after implantation.

The upside down Gore Excluder contralateral leg without extracorporeal predeployment for aortic or iliac aneurysm exclusion

Endovascular techniques, including branched devices to preserve the internal iliac artery are evolving rapidly, but in cases in which the diameter of the proximal sealing zone is larger than that of the distal sealing zone, a reversed tapered device is needed. We describe the off label use of the Gore Excluder contralateral leg endoprosthesis in an upside down configuration to accommodate this diameter mismatch. The preinsertion technical steps of stent graft preparation, which do not require extracorporeal predeployment, are described in detail. As such, an aneurysm of the internal iliac artery and a saccular abdominal aortic aneurysm were successfully excluded.

Randomized trial of Legflow® paclitaxel eluting balloon and stenting versus standard percutaneous transluminal angioplasty and stenting for the treatment of intermediate and long lesions of the superficial femoral artery (RAPID trial): study protocol for a randomized controlled trial

BackgroundRestenosis after percutaneous transluminal angioplasty (PTA) of the superficial femoral artery (SFA) may occur in 45% of patients at 2 years follow-up. Paclitaxel-coated balloons have been found to reduce neointimal hyperplasia, and thus reduce restenosis. Recently, the Legflow® paclitaxel-coated balloon (Cardionovum Sp.z.o.o., Warsaw, Poland) (LPEB) has been introduced. This balloon is covered with shellac, a Food and Drug Administration (FDA) approved natural resin, to obtain an equally distributed tissue concentration of paclitaxel. The RAPID trial is designed to assess restenosis after PTA using the Legflow balloon combined with nitinol stenting versus uncoated balloons with nitinol stenting in SFA lesions >5 cm.Methods/DesignA total of 176 adult patients with Rutherford class 2 to class 6 symptoms due to intermediate (5–15 cm) or long (>15 cm) atherosclerotic lesions in the SFA will be randomly allocated for treatment with LPEB with nitinol stenting or uncoated balloon angioplasty with stenting. Stenting will be performed using the Supera® stent in both groups (IDEV Technologies Inc., Webster, TX). The primary endpoint is the absence of binary restenosis of the treated SFA segment. Secondary outcomes are target lesion revascularization (TLR), clinical and hemodynamic outcome, amputation rate, mortality rate, adverse events, and device-specific adverse events. Follow up consists of four visits in which ankle-brachial indices (ABI), toe pressure measurements, and duplex ultrasound (DUS) will be performed. Furthermore, a peripheral artery questionnaire (PAQ) will be completed by the patients at each follow-up. In the event that DUS reveals a symptomatic >50% restenosis, or a >75% asymptomatic restenosis, additional digital subtraction angiography will be performed with any necessary re-intervention.DiscussionThe RAPID trial is a multicenter randomized controlled patient blind trial that will provide evidence concerning whether the use of the Legflow paclitaxel/shellac coated balloons with nitinol stenting significantly reduces the frequency of restenosis in intermediate and long SFA lesions compared to standard PTA and stenting.Trial registrationISRCTN47846578

Report of two in situ reconstructions with a saphenous spiral vein graft of Coxiella burnetii-infected aneurysms of the abdominal aorta

Coxiella burnetii is a rare cause of vascular infections. Yet, Q fever is endemic in the southern part of The Netherlands. This report describes two patients--from the southern part of The Netherlands--with infected aneurysms of the abdominal aorta caused by Coxiella burnetii. Both patients underwent surgical debridement, in situ reconstruction with a great saphenous vein spiral graft, and a transmesenteric omentumplasty. One patient fully recovered, while the other died due to ischemic complications. A multidisciplinary work-up approach to treat infected abdominal aneurysms is proposed, including adequate surgical treatment and long-term antibiotic administration.

Intraplaque neovascularization and hemorrhage: markers for cardiovascular risk stratification and therapeutic monitoring.

Atherosclerotic disease results in major clinical events and remains a leading cause of morbidity and mortality in the western World. Atherosclerotic plaques have a heterogeneous presentation. Atherosclerotic plaques with a vulnerable phenotype have been associated with an increased risk for cardiovascular complications. Intraplaque neovascularization and hemorrhage are histopathological features that have been linked with the vulnerable plaque. The role of intraplaque neovascularization and hemorrhage in plaque destabilization and lesion progression has gained serious interest. Intraplaque neovascularization and hemorrhage have been correlated with the occurrence of prior cardiovascular events and have predictive value for the occurrence of future cardiovascular events. Pharmacological interventions showed an inhibiting effect of lipid-lowering drugs on plaque neovascularization. Imaging modalities such as contrast-enhanced ultrasound or MRI are able to visualize intraplaque neovascularization and hemorrhage noninvasively. Consequently, detection of intraplaque neovascularization and hemorrhage visualized with noninvasive imaging might improve the stratification of ‘high-risk’ patients.

Vascular access outcome in the elderly dialysis patient in combination with the quality of life.

Purpose: We performed a retrospective study on hemodialysis fistulae in patients aged 75 years and older. Methods: Dialysis records of 2 hospitals were searched for patients of 75 years and older who had primary autologous radiocephalic arteriovenous fistulae (RCAVFs) and brachiocephalic arteriovenous fistulae (BCAVFs). Outcome measures were primary, primary-assisted, and secondary patency rates. Also, quality of life (QOL) was measured. Results: A total of 107 fistulae were placed in 90 patients; 65 (61%) RCAVFs and 42 (39%) BCAVFs were created. The primary patency rate (P = .026) and the primary-assisted patency rate (P = .016) of BCAVFs were significantly higher than that of RCAVFs. Secondary patency rates at 1 year (P = .01) and 2 years (P = .035) were higher in BCAVFs than in RCAVFs. Conclusions: The BCAVFs give significantly higher primary and primary-assisted patency rates and also significantly higher secondary patency rates at 1 and 2 years. Therefore, we suggest the placement of elbow fistulae in the elderly patients. The QOL was surprisingly high in this population despite a high mortality rate.

Self-reported symptoms on questionnaires and anatomic lesions on duplex ultrasound examinations in patients with peripheral arterial disease

OBJECTIVE Whether a typical patient and symptom profile is associated with proximal or distal lesions in lower extremity peripheral arterial disease (PAD) is unknown. Knowing which patient characteristics, exertional leg symptoms, and cardiovascular risk profile accompany the anatomic lesion location may facilitate a more tailor-made management of PAD. METHODS This cross-sectional study comprised 701 patients from two vascular surgery outpatient clinics with new-onset symptoms of PAD (Fontaine 2) who underwent duplex ultrasound (DUS) examinations from March 2006 to March 2011. The main outcome measures were patient characteristics, self-reported leg symptoms, and cardiovascular risk factors as documented from questionnaires and medical records. Peripheral lesion information, categorized by proximal and distal lesions, was obtained from DUS examinations. Multivariable logistic regression analyses were performed of proximal vs nonproximal lesions, distal vs nondistal lesions, and proximal and distal vs absence of having both lesions to assess relationships between patient characteristics, leg symptom categories (typical vs atypical leg symptoms), cardiovascular risk factors, and anatomic lesion location. RESULTS Lesions were proximal in 270 (38.5%), distal in 441 (62.9%), and proximal and distal in 94 (13.4%). Patients with proximal lesions were younger (odds ratio [OR], 0.94; P < .0001) and less likely to be obese (OR, 0.34; P < .0001) than those without proximal lesions. Older age (OR, 1.07; P < .0001), male sex (OR, 1.96; P = .003), being without a partner (OR, 2.24; P = .004), and lower anxiety scores (OR, 0.42; P = .003) were associated with distal lesions. Patients with both lesions were more likely to be single (OR, 2.30; P = .010) and less likely to be obese (OR, 0.24; P = .009). No distinguishing leg symptom pattern was observed for patients with proximal lesions. Intermittent claudication was more frequently reported in those with distal lesions (P = .011). Although buttock and thigh pain seemed to be somewhat more present in proximal lesions (P < .01) and calf pain more in distal lesions (P < .001), patients still reported pain at a variety of levels throughout their legs, regardless of the anatomic lesion location. CONCLUSIONS Two distinctive PAD phenotypes-each with its own characteristics and risk factors-emerged by anatomic lesion location; however, PAD-specific leg symptoms did not always reflect the anatomic lesion location. These findings may open new opportunities to better tailor PAD management to these two PAD subgroups and may raise awareness about not relying on self-reported symptoms to guide further diagnostic imaging and peripheral lesion management.