Long Term Results of Kissing Stents in the Aortic Bifurcation.

BACKGROUND: To evaluate the long-term outcome after aortoiliac kissing stent placement and to analyze variables, which potentially influence the outcome of endovascular reconstruction of the aortic bifurcation. METHODS: All patients treated with aortoiliac kissing stents at our institution between April 1995 and August 2011 were retrospectively identified from a prospective single-center database. Data regarding patient characteristics (age, gender, smoking, cardio- and cerebrovascular risk factors, hyperlipidaemia, diabetes mellitus and use of antihypertensive medication), symptoms, pre-interventional examination and imaging, procedural details and follow-up were retrieved. Patency rates were calculated with Kaplan-Meier analysis. Factors affecting the patency were determined with Cox uni- and multivariate analysis. RESULTS: A total of 215 patients (63% men, mean age 61 ±â€ˆ10 years) were included. The median follow-up period was 31 (IQR 47.1) months. Primary, primary assisted, and secondary patency rates were 97%, 97%, and 99%, respectively, at one month; 92%, 95% and 94% at four months; 75%, 86%, and 91% at two years; 70%, 81%, and 91% at 5 years; and 67%, 81%, and 91% at ten years. Younger age and previous aortoiliac treatment were predictors for reduced primary and primary assisted patency. Smoking, previous aortoiliac intervention, TASC C and D lesions were predictors for reduced secondary patency. CONCLUSIONS: Reconstruction of the aortoiliac bifurcation with kissing stents is feasible, safe and effective in all types of lesions with satisfying long term patencies. TASC C and D lesions are associated with a higher occlusion rate. Younger age and previous aortoiliac interventions are predictors for reduced primary and primary assisted patency.

Superior two-year results of externally unsupported polyester compared to supported grafts in above-knee bypass grafting: a multicenter randomised trial.

OBJECTIVES: The aim of this study was to compare externally supported thin wall knitted polyester (P-EXS) and externally unsupported thin wall knitted polyester (P-non-EXS) for above-knee (AK) femoro-popliteal bypass grafting. DESIGN: A prospective multicenter randomised clinical trial. MATERIAL AND METHODS: Between 1999 and 2008, 265 AK femoro-popliteal bypass grafts (6 mm in diameter) were performed, including 136 P-EXS and 129 P-non-EXS. The selection of patients was based on the presence of disabling claudication or critical ischaemia. Follow-up took place at 3, 6, 12, 18, and 24 months and included clinical examination and duplex ultrasonography. The main end points of this study were primary patency rates at one and two years. Secondary end points were mortality, and primary assisted and secondary patency rates. Cumulative patency rates were calculated with life-table analysis and log-rank testing. RESULTS: The 1-year primary, primary assisted and secondary patency rates were 65%, 70% and 84%, respectively, for P-EXS and 76% (p = 0.05), 82% (p = 0.03) and 88% (p = 0.35), respectively, for P-non-EXS. Two-year primary, primary assisted and secondary patency rates were 45%, 57% and 70%, respectively, for P-EXS and 62% (p = 0.003), 75% (p = 0.005) and 84% (p = 0.02), respectively, for P-non-EXS. The overall mortality rate after two years was 11.3%. CONCLUSION: In above-knee femoro-popliteal bypass grafting patency rates of externally supported knitted polyester grafts were inferior to their unsupported counterpart. ISRCTN: At the time this study started this number was not the standard.

Surgical options for the management of visceral artery aneurysms.

Visceral artery aneurysm (VAA) is a rare entity but increased use of abdominal imaging has led to an increased prevalence. Rupture is related to a high mortality rate. Open repair, endovascular treatment and laparoscopic techniques have been described as treatment options. In this systematic review we describe the surgical options for treating VAA. A literature search identified articles focussing on the key issues of visceral artery aneurysms and surgical options using the Pubmed and Cochrane databases. Case reports dominate the literature about VAA. Twenty-seven small case series and ten review articles have been published in the last 20 years concerning the surgical options for VAA. The evidence does not exceed level 3. Surgical treatment is dictated by both patient and aneurysm characteristics. Whether VAA should be treated largely depends upon age, gender, presence of hypertension (e.g. in renal aneurysm), aneurysm size and presentation. Aneurysm size and characteristics, anatomical location and presence of collateral circulation dictate the surgical option to be chosen. The mortality and morbidity rates after elective open repair are low. Literature about surgical options for treating VAA remains scarce. Only a few clinical trials have shown the possibilities and results of open surgical repair. In general, there is no consensus on the surgical treatment of VAA and the highest level of evidence is based upon expert opinions.

Accuracy of FDG-PET-CT in the diagnostic work-up of vascular prosthetic graft infection.

OBJECTIVES: To investigate the diagnostic accuracy of fluoro-2-deoxy-d-glucose positron emission tomography (FDG-PET) compared with computed tomography (CT) scanning and added value of fused FDG-PET-CT in diagnosing vascular prosthetic graft infection. DESIGN: Prospective cohort study with retrospective analysis. MATERIALS: Twenty five patients with clinically suspected vascular prosthetic infection underwent CT and FDG-PET scanning. METHODS: Two nuclear medicine physicians assessed the FDG-PET scans; all CT scans were assessed by two radiologists. Fused FDG-PET/CT were judged by the radiologist and the nuclear medicine physician. The concordance between CT and FDG-PET and the inter-observer agreement between the different readers were investigated. RESULTS: Fifteen patients had a proven infection by culture. Single FDG-PET had the best results (sensitivity 93%, specificity 70%, positive predictive value 82% and negative predictive value 88%). For CT, these values were 56%, 57%, 60% and 58%, respectively. Fused CT and FDG-PET imaging also showed high sensitivity and specificity rates and high positive and negative values. Inter-observer agreement for FDG-PET analysis was excellent (kappa = 1.00) and moderate for CT and fused FDG-PET-CT analysis (0.63 and 0.66, respectively). CONCLUSION: FDG-PET scanning showed a better diagnostic accuracy than CT for the detection of vascular prosthetic infection. This study suggests that FDG-PET provides a useful tool in the work-up for diagnosis of vascular prosthetic graft infection.

Surgical strategy in patients with secondary and tertiary hyperparathyroidism. A bi-institutional series.

BACKGROUND: Although total parathyroidectomy with forearm autotransplantation is a widely accepted treatment for patients with secondary/tertiary hyperparathyroidism (HPT) some debate persists about the optimal surgical strategy. In particular, the question what to do when less than four parathyroid glands can be found during surgery has yet to be resolved. The aim of this retrospective study was to review the outcome of total parathyroidectomy with autotransplantation and to assess the proper procedure (to autotransplant or not) when finding less than 4 glands after extensive surgical exploration. METHODS: Between 1995 and 2005, parathyroidectomy was performed in 74 patients in two affiliated centers. In this case-control study both clinical and biochemical outcomes of a total or subtotal parathyroidectomy were compared. The parathyroid hormone (PTH), serum calcium concentration, phosphate and alkaline phosphatase levels were monitored preoperatively, 1 and 12 months postoperatively. RESULTS: Sixty five patients underwent a total parathyroidectomy and nine patients underwent a subtotal parathyroidectomy. Persistent HPT was seen in nine patients (12%). Recurrent HPT was seen in eight patients (11%). There were no significant differences between the group with > or = 4 glands excised and the group with three glands excised regarding serum PTH levels after 12 months and the number of patients with a hypo- or hyperparathyroidism (persistent or recurrent). Procedure related morbidity was minimal. CONCLUSIONS: Total parathyroidectomy with forearm autotransplantation is safe and effective for patients with secondary/tertiary hyperparathyroidism. In case of not finding a fourth gland after extensive surgical exploration, our general advice is to proceed as planned with the autotransplantation.

Culture results from wound biopsy versus wound swab: does it matter for the assessment of wound infection?

OBJECTIVES: The aim of this study was to determine whether assessment of wound infection differs when culture results from wound biopsy versus wound swab are available in clinical practice. METHODS: For 180 eligible patients, a swab and biopsy were taken from one wound during a regular appointment at a wound care facility in eastern Netherlands. Culture results from both methods were supplemented with clinical information and provided to a panel of six experts who independently assessed each wound as infect or not, separately for swab and biopsy. Assessments for biopsy and swab were compared for the complete expert panel, and for individual experts. RESULTS: The complete expert panel provided the same wound assessment based on (clinical information and) culture results from wound biopsy and wound swab in 158 of 180 wounds (87.8%, kappa 0.67). For individual experts, agreement between biopsy and swab varied between 77% and 96%. However, there were substantial differences between experts: the same assessment was provided in 62 (34.4%) to 76 (42.2%) wounds for swab and biopsy respectively. CONCLUSIONS: Assessment of infection does not significantly differ when culture results from swabs or biopsies are available. The substantial variability between individual experts indicates non-uniformity in the way wounds are assessed. This complicates accurate detection of infection and comparability between studies using assessment of infection as reference standard.

Prospective randomized study of carotid endarterectomy with Fluoropassiv thin wall carotid patch versus venous patch.

INTRODUCTION: The practice of carotid endarterectomy (CEA) with patch angioplasty is more effective compared to primary closure. However, the type of patch material remains a controversy. The Fluoropassiv thin wall carotid patch is a polyester patch with an interpenetrating, nanometer-scale, solvent-applied surface modification, based on a biocompatible fluoropolymer. The present pilot study is the first clinical trial evaluating results of CEA with Fluoropassiv versus venous patch. MATERIALS/METHODS: Eighty-seven patients were randomized to 42 Fluoropassiv patching and 45 venous patching. Patients were observed by a vascular surgeon and a neurologist and scanned using duplex ultrasound with a follow-up of 2 years. No patients were lost to follow-up. Restenosis was defined as a Peak Systolic Velocity ratio >2.6, lumen reduction >50%. RESULTS: Perioperative stroke rate was 2.4% in the Fluoropassiv group and 8.9% in the venous group (p=0.02; 1 regressive, 4 non-regressive strokes). Multivariate analysis showed that bilateral carotid stenosis and stroke as indication for CEA were related to perioperative stroke. There was no link between perioperative stroke and patch type after correction for these factors. Patch type had no influence on operation time, clamp time, cranial nerve damage, hypertension, hematoma, infections, time to discharge, or early thromboembolic events. There were no significant differences between the Fluoropassiv and the venous group for cumulative mortality (respectively 4.4 vs 4.8%), patch occlusion (4.8 vs 2.2%), or stroke rate during 2 year follow-up (2.2 vs 2.4%). CONCLUSION: This first clinical study with the Fluoropassiv thin wall carotid patch showed no enhanced thrombogenicity compared to a venous patch. The Fluoropassiv patch is not related to a higher rate of postoperative bleeding events either.

Application of PET/SPECT imaging in vascular disease.

BACKGROUND: Nuclear medicine imaging differs from other imaging modalities by showing physiological processes instead of anatomical details. OBJECTIVE: To describe the current applications of positron emission tomography (PET) and single photon emission computed tomography (SPECT) as a diagnostic tool for vascular disease as relevant to vascular surgeons. METHODS: A literature search identified articles focussing on vascular disease and PET or SPECT using the Pubmed database. Manual cross referencing was also performed. RESULTS: PET and SPECT may be used to assess plaque vulnerability, biology of aneurysm progression, prosthetic graft infection, and vasculitis. The ability to combine computerized tomography scanning or magnetic resonance imaging with PET or SPECT adds detailed anatomical information and enhances the potential of nuclear medicine imaging in the investigation of vascular disease. DISCUSSION: Considerable further information will be needed to define whether and where PET or SPECT will fit in a clinical strategy. The necessary validation studies represent an exciting challenge for the future but also may require the development of interdisciplinary imaging groups to integrate expertise and optimize nuclear diagnostic potential.

Clinical relevance of advanced glycation endproducts for vascular surgery.

Atherosclerosis is the main contributor to cardiovascular disease and leads to intimal plaque formation, which may progress to plaque rupture with subsequent thromboembolic events and/or occlusion of the arterial lumen. There is increasing evidence that the development or progression of atherosclerosis is associated with advanced glycation endproducts (AGEs). AGEs are a heterogeneous group of compounds formed by the non-enzymatic reaction of reducing sugars with proteins, lipids, and nucleic acids. An increased understanding of the mechanisms of formation and interaction of AGEs has allowed the development of several potential anti-AGE strategies. This review summarizes AGE formation and biochemistry, the pathogeneic role of AGEs in cardiovascular disease, anti-AGE therapies and clinical relevance to vascular surgery.

Diverging effects of diabetes mellitus in patients with peripheral artery disease and abdominal aortic aneurysm and the role of advanced glycation end-products: ARTERY study - protocol for a multicentre cross-sectional study.

INTRODUCTION: Diabetes mellitus is a well-defined risk factor for peripheral artery disease (PAD), but protects against the development and growth of abdominal aortic aneurysm (AAA). Diabetes mellitus is associated with arterial stiffening and peripheral arterial media sclerosis. Advanced glycation end-products (AGEs) are increased in diabetes mellitus and cardiovascular disease. AGEs are known to form cross-links between proteins and are associated with arterial stiffness. Whether AGEs contribute to the protective effects of diabetes mellitus in AAA is unknown. Therefore, the ARTERY (Advanced glycation end-pRoducts in patients with peripheral arTery disEase and abdominal aoRtic aneurYsm) study is designed to evaluate the role of AGEs in the diverging effects of diabetes mellitus on AAA and PAD. METHODS AND ANALYSIS: This cross-sectional multicentre study will compare the amount, type and location of AGEs in the arterial wall in a total of 120 patients with AAA or PAD with and without diabetes mellitus (n=30 per subgroup). Also, local and systemic vascular parameters, including pulse wave velocity, will be measured to evaluate the association between arterial stiffness and AGEs. Finally, AGEs will be measured in serum, urine, and assessed in skin with skin autofluorescence using the AGE Reader. ETHICS AND DISSEMINATION: This study is approved by the Medical Ethics committees of University Medical Center Groningen, Martini Hospital and Medisch Spectrum Twente, the Netherlands. Study results will be disseminated through peer-reviewed journals and scientific events. TRIAL REGISTRATION NUMBER: trialregister.nl NTR 5363.

Characterization of an 8-hydroxy-5-deazaflavin:NADPH oxidoreductase from Streptomyces griseus.

An 8-hydroxy-5-deazaflavin-dependent oxidoreductase was isolated from the actinomycete Streptomyces griseus and purified 590-fold with 72% overall yield. The enzyme catalyzes electron transfer between 8-hydroxy-5-deazaflavins and NADPH. It seems to be more specific than methanogenic oxidoreductase as it has an absolute requirement for both the 5-deazaflavin structure and the presence of an 8-hydroxy group in the substrate. A molecular weight of 42,000 was found with gel permeation chromatography, while SDS gel electrophoresis indicated the presence of two identical subunits. Maximal enzymatic activity was found at 0.32 M NaCl and pH 5.9 for reduction of 8-hydroxy-5-deazaflavin and pH 7.9 for the reverse reaction. From the kinetic constants it was estimated that the main function of this oxidoreductase is probably to provide cells with reduced 8-hydroxy-5-deazaflavin to be used in specific reduction reactions. These results indicate the occurrence of 8-hydroxy-5-deazaflavin-dependent electron transfer in microorganisms not belonging to the archaebacteria.

Endovascular treatment of ruptured abdominal aortic aneurysm: is there a long-term benefit at follow-up?

AIM: Several studies have shown the feasibility of endovascular repair of ruptured abdominal aortic aneurysms (rEVAR). However, the role and value of rEVAR remains controversial due to selection bias and lack of long-term results. In the present study we describe our short- and long-term results of treating patients with rEVAR irrespective of hemodynamic condition and challenging anatomy. METHODS: In April 2006 we started the single centre prospective non-randomised Ruptured Aneurysm Study (RASA). During a four year enrolment period all consecutive patients presenting with infrarenal ruptured AAA (rAAA, N.=117) were assessed for preferential rEVAR treatment. A rAAA was defined as extravasation of blood or hematoma outside the AAA due to transmural tear in the infrarenal abdominal aorta wall documented by preoperative computed tomography (CT) angiography examination or during open repair. Patients with challenging anatomy (infrarenal neck length below 15 mm and neck angulation above 60 degrees) were included as part of a damage control concept. Complication and mortality rates were studied at 30 days and yearly afterwards. RESULTS: Thirty-five patients (33% of all admitted rAAA) were treated with rEVAR and 42% of them were considered hemodynamically unstable (systolic blood pressure <100 mmHg) and 30% had challenging AAA anatomy. The mortality rate at 30 days in the rEVAR group was 17%, in the open repair group 31%, and in the entire rAAA group (including abstained patients) 36%. During the first 30 days, 18 rEVAR patients experienced complications with nine re-interventions as a result. Long-term mortality of the rEVAR patients was 34% after a median follow-up of 3.4 years. All deaths after one year follow-up were non-AAA related. Multivariate analysis shows that Hardman index, presence of peripheral arterial obstructive disease and lowest systolic blood pressure during surgery are independently associated with long-term survival. Challenging rAAA anatomy was not associated with impaired survival. CONCLUSION: Our study shows that rEVAR is feasible irrespective of hemodynamic condition and that it is associated with relative low mortality rates. Challenging rAAA anatomy may not affect overall long-term survival, but six out of ten patients remain unsuitable for rEVAR because of inappropriate anatomy.

Medical treatment in carotid artery intervention.

Medical treatment has a pivotal role in the treatment of patients with occlusive carotid artery disease. Large trials have provided the justification for operative treatment besides medical treatment in patients with recent significant carotid artery stenosis two decades ago. Since then, medical therapy has evolved tremendously. Next to aspirin, antiplatelet regimens acting on a different level in the modulation of platelet aggregation have made their entry. Moreover, statin therapy has been introduced. These changes among others in secondary stroke prevention, along with better understanding in life-style adjustments and perioperative medical management, have led to a decrease in stroke recurrence. Secondary prevention is therefore now the most important pillar of medical therapy. It consists of antiplatelet therapy, statins and blood pressure lowering agents in all patients. Small adjustments are recommended for those patients referred for invasive treatment. Moreover, long-term medical treatment is imperative. In this article, we summarize current evidence in literature regarding medical management in patients with previous stroke or TIA.

Increased accumulation of skin advanced glycation end-products precedes and correlates with clinical manifestation of diabetic neuropathy.

AIMS/HYPOTHESIS: The accumulation of AGE is related to the progression of the renal, retinal and vascular complications of diabetes. However, the relationship with diabetic neuropathy remains unclear. We recently showed that skin autofluorescence, measured non-invasively with an AutoFluorescence Reader (AFR), could be used to assess skin AGE accumulation. We evaluated the relationship between skin autofluorescence and the severity of diabetic neuropathy. MATERIALS AND METHODS: Skin autofluorescence in arbitrary units (AU) was assessed in 24 diabetic patients with a history of neuropathic foot ulceration (NP(+)), 23 diabetic patients without clinical neuropathy (NP(-)) and 21 control subjects, using the AFR. Arterial occlusive disease was excluded in all. The severity of foot ulceration was assessed by the Wagner score. Peripheral nerve function was assessed by neurography, measuring motor and sensory nerve conduction velocity and amplitude of the median, peroneal and sural nerves. Heart rate variability (HRV) and baroreflex sensitivity (BRS) were measured by Finapres to assess autonomic nervous function. RESULTS: Autofluorescence was increased in NP(-) compared with control subjects. In NP(+) patients, autofluorescence was further increased and correlated with the Wagner score. Autofluorescence correlated negatively with nerve conduction velocity and amplitude, HRV and BRS in both NP(+) and NP(-) groups. Autofluorescence correlated with age, diabetes duration, mean HbA(1)c of the previous year, serum creatinine level, presence of microalbuminuria and severity of diabetic retinopathy. CONCLUSIONS/INTERPRETATION: Skin autofluorescence correlates with the severity of peripheral and autonomic nerve abnormalities in diabetes, even before being clinically manifest. The AFR may be a convenient and rapid clinical tool for assessing risk of progression of long-term diabetic complications.

A lower prevalence of atopy symptoms in children with type 1 diabetes mellitus.

BACKGROUND: The Th1/Th 2 concept is a model to understand the pathophysiology of certain diseases. Atopic diseases (asthma, eczema and hayfever) are characterized by a chronic inflammatory reaction that is dominated by Th 2 cells, and type 1 diabetes mellitus (DM) is Th1 cell dominated. Because it is known that Th1 and Th 2 cells reciprocally counteract each other, it can be speculated that the prevalence of Th 2-mediated disease is lower in patients with Th1-mediated disease. OBJECTIVE: To compare the prevalence of atopic diseases between children with DM and age-matched controls. METHODS: Parents of children with DM were requested by Dutch paediatricians to complete the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire on the prevalence of atopic diseases. A control group was derived from a Dutch cross-sectional survey (the ISAAC2 study). RESULTS: We received 555 completed questionnaires, which is estimated to be 25% of the total number of Dutch children with DM. The control group consisted of 777 children. After age-matching, the questionnaires of 188 DM patients were used. Symptoms of asthma, hayfever and eczema were reported less in the group of children with DM compared with the control group (wheeze last year, OR 0.796, 95% CI 0.408-1.554; hayfever symptoms last year, OR 0.642, 95% CI 0.369-1.118; eczema symptoms last year, OR 0.693, 95% CI 0.430-1.115). CONCLUSION: The lower prevalence of astma, hayfever and eczema symptoms in DM patients compared with age-matched controls, although not statistically significant, is consistent with the Th1/Th 2 concept.

Simple non-invasive assessment of advanced glycation endproduct accumulation.

AIMS/HYPOTHESIS: The accumulation of AGE is thought to play a role in the pathogenesis of chronic complications of diabetes mellitus and renal failure. All current measurements of AGE accumulation require invasive sampling. We exploited the fact that several AGE exhibit autofluorescence to develop a non-invasive tool for measuring skin AGE accumulation, the Autofluorescence Reader (AFR). We validated its use by comparing the values obtained using the AFR with the AGE content measured in extracts from skin biopsies of diabetic and control subjects. METHODS: Using the AFR with an excitation light source of 300-420 nm, fluorescence of the skin was measured at the arm and lower leg in 46 patients with diabetes (Type 1 and 2) and in 46 age- and sex-matched control subjects, the majority of whom were Caucasian. Autofluorescence was defined as the average fluorescence per nm over the entire emission spectrum (420-600 nm) as ratio of the average fluorescence per nm over the 300-420-nm range. Skin biopsies were obtained from the same site of the arm, and analysed for collagen-linked fluorescence (CLF) and specific AGE: pentosidine, N(epsilon)-(carboxymethyl)lysine (CML) and N(epsilon)-(carboxyethyl)lysine (CEL). RESULTS: Autofluorescence correlated with CLF, pentosidine, CML, and CEL ( r=0.47-0.62, p