In Vivo Quantification of Cardiac-Pulsatility-Induced Motion Before and After Double-Branched Endovascular Aortic Arch Repair

The Relay^®Branch stent-graft (Terumo Aortic, Sunrise, FL, USA) offers a custom-made endovascular solution for complex aortic arch pathologies. In this technical note, a modified electrocardiography (ECG)-gated computed tomography (CT)-based algorithm was applied to quantify cardiac-pulsatility-induced changes of the aortic arch geometry and motion before and after double-branched endovascular repair (bTEVAR) of an aortic arch aneurysm. This software algorithm has the potential to provide novel and clinically relevant insights in the influence of bTEVAR on aortic anatomy, arterial compliance, and stent-graft dynamics.

Real World Practice Deviation from Nationwide Guidelines in Patients with Intermittent Claudication

OBJECTIVE

Patients with intermittent claudication (IC) are initially treated with supervised exercise therapy (SET), as advised by national and international guidelines. Dutch health insurance companies and the Dutch National Health Care Institute suggested an 87% compliance rate with these guidelines in the Netherlands in 2017 and judged this to be undesirably low. The aim of this study was to evaluate compliance with IC guidelines and to elaborate on the reasons for deviating from them (practice variation) in a large teaching hospital.

METHODS

A retrospective single centre cohort study was conducted at a large teaching hospital in the Netherlands. In total, 420 patients with newly diagnosed IC between 1 January 2017 and 31 December 2018 were analysed. Data included risk profiles and prescribed therapies.

RESULTS

For all 420 included patients, the compliance rate with the guidelines for SET was 80.5%. The rate of adequately motivated and defensible practice variation was 15.7%; the rate of unjustified practice variation was 3.8%. Meaningful care was seen in 96.2% of cases.

CONCLUSION

Deviation from IC guidelines was found in 19.5% of patients. Almost three quarters of this deviation can be explained by the decision to provide personalised, meaningful care.

Editor's Choice - Nationwide Analysis of Patients Undergoing Iliac Artery Aneurysm Repair in the Netherlands

OBJECTIVE

The new 2019 guideline of the European Society for Vascular Surgery (ESVS) recommends consideration for elective iliac artery aneurysm (eIAA) repair when the iliac diameter exceeds 3.5 cm, as opposed to 3.0 cm previously. The current study assessed diameters at time of eIAA repair and ruptured IAA (rIAA) repair and compared clinical outcomes after open surgical repair (OSR) and endovascular aneurysm repair (EVAR).

METHODS

This retrospective observational study used the nationwide Dutch Surgical Aneurysm Audit (DSAA) registry that includes all patients who undergo aorto-iliac aneurysm repair in the Netherlands. All patients who underwent primary IAA repair between 1 January 2014 and 1 January 2018 were included. Diameters at time of eIAA and rIAA repair were compared in a descriptive fashion. The anatomical location of the IAA was not registered in the registry. Patient characteristics and outcomes of OSR and EVAR were compared with appropriate statistical tests.

RESULTS

The DSAA registry comprised 974 patients who underwent IAA repair. A total of 851 patients were included after exclusion of patients undergoing revision surgery and patients with missing essential variables. eIAA repair was carried out in 713 patients, rIAA repair in 102, and symptomatic IAA repair in 36. OSR was performed in 205, EVAR in 618, and hybrid repairs and conversions in 28. The median maximum IAA diameter at the time of eIAA and rIAA repair was 43 (IQR 38-50) mm and 68 (IQR 58-85) mm, respectively. Mortality was 1.3% (95% CI 0.7-2.4) after eIAA repair and 25.5% (95% CI 18.0-34.7) after rIAA repair. Mortality was not significantly different between the OSR and EVAR subgroups. Elective OSR was associated with significantly more complications than EVAR (intra-operative: 9.8% vs. 3.6%, post-operative: 34.0% vs. 13.8%, respectively).

CONCLUSION

In the Netherlands, most eIAA repairs are performed at diameters larger than recommended by the ESVS guideline. These findings appear to support the recent increase in the threshold diameter for eIAA repair.

Radiation exposure in an endovascular aortic aneurysm repair program after introduction of a hybrid operating theater

BACKGROUND

A hybrid operating theater (HOT) enables optimal image quality, improved ergonomics, and excellent sterility for complex endovascular and hybrid procedures. We hypothesize that the commissioning of a new HOT involves a learning curve. It is unclear how steep the learning curve of these advanced HOTs is. The main purpose of this research was to evaluate radiation exposure parameters in a new HOT for a team of vascular surgeons experienced with infrarenal endovascular aneurysm repair (EVAR) procedures in a conventional operating room with a mobile C-arm. In addition, a comparison of the dose-area product (DAP) achieved in this study and in the literature was made.

METHODS

Before commissioning of the HOT, four vascular surgeons completed a comprehensive HOT training program. From the commissioning of the HOT, clinical and procedural data for all consecutive acute and elective patients treated with EVAR were retrospectively collected for a period of 18 months (January 2016-June 2017). A literature review was conducted of the dose-area product in EVAR procedures performed with a dedicated fixed system or mobile C-arm to analyze how this study performed compared with the literature.

RESULTS

In the 18-month study period, 77 patients were treated with EVAR (59 electively and 18 acutely), from whom the data were obtained. There was no significant change in radiation exposure parameters over time. From the commissioning of the HOT, EVAR procedures were performed with radiation exposure parameters similar to those of studies found in experienced vascular centers using fixed systems.

CONCLUSIONS

Concerning radiation exposure parameters, the commissioning of a new HOT was not accompanied by a learning curve. Radiation exposure parameters achieved in this study were similar to those of studies from experienced and dedicated vascular centers.

Atmospheric Pressure and Abdominal Aortic Aneurysm Rupture: Results From a Time Series Analysis and Case-Crossover Study

BACKGROUND

Associations between atmospheric pressure and abdominal aortic aneurysm (AAA) rupture risk have been reported, but empirical evidence is inconclusive and largely derived from studies that did not account for possible nonlinearity, seasonality, and confounding by temperature.

METHODS

Associations between atmospheric pressure and AAA rupture risk were investigated using local meteorological data and a case series of 358 patients admitted to hospital for ruptured AAA during the study period, January 2002 to December 2012. Two analyses were performed-a time series analysis and a case-crossover study.

RESULTS

Results from the 2 analyses were similar; neither the time series analysis nor the case-crossover study showed a significant association between atmospheric pressure ( P = .627 and P = .625, respectively, for mean daily atmospheric pressure) or atmospheric pressure variation ( P = .464 and P = .816, respectively, for 24-hour change in mean daily atmospheric pressure) and AAA rupture risk.

CONCLUSION

This study failed to support claims that atmospheric pressure causally affects AAA rupture risk. In interpreting our results, one should be aware that the range of atmospheric pressure observed in this study is not representative of the atmospheric pressure to which patients with AAA may be exposed, for example, during air travel or travel to high altitudes in the mountains. Making firm claims regarding these conditions in relation to AAA rupture risk is difficult at best. Furthermore, despite the fact that we used one of the largest case series to date to investigate the effect of atmospheric pressure on AAA rupture risk, it is possible that this study is simply too small to demonstrate a causal link.

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.

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 ± 10 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.

Endarterectomy or carotid artery stenting: the quest continues part two

BACKGROUND

Although randomized trials on carotid artery stenting (CAS) could not establish its equivalence to carotid endarterectomy (CEA) in patients with symptomatic carotid disease, CAS is rapidly evolving. Data on long-term outcome after CAS from randomized trials have now become available and ongoing, prospectively held registries frequently publish their results in increasing numbers of patients. We have therefore reviewed the currently available literature and provide an update of our previous article on this topic.

DATA SOURCES

PubMed literature searches were performed to identify relevant studies regarding current status of CEA and stenting for symptomatic carotid stenosis.

CONCLUSIONS

The efficacy of CAS in patients with symptomatic carotid artery stenosis remains unclear because of varying results in randomized trials. Although multiple registries do report promising results after CAS, peri-interventional stroke/death rates still exceed those rates currently found after CEA. Therefore, CEA remains the "gold standard" in treating these patients.

Mesenteric stenosis, collaterals, and compensatory blood flow

BACKGROUND

The mesenteric circulation has an extensive collateral network. Therefore, stenosis in one or more mesenteric arteries does not necessarily lead to symptoms. The objective of this study was to determine the effect of collateral flow on celiac artery (CA) and superior mesenteric artery (SMA) duplex parameters.

METHODS

Between 1999 and 2007, a cohort of 228 patients analyzed for suspected chronic mesenteric syndrome was studied. Stenosis of the mesenteric vessels and collateral flow patterns were identified on angiography and categorized. The effect of stenosis in one mesenteric vessel and the presence of collaterals from the other unaffected vessel was examined in both the CA and SMA.

RESULTS

Stenosis of the CA resulted in a significantly higher peak systolic velocity (PSV) and end-diastolic velocity in the normal SMA without stenosis. This was also found for the CA without stenosis in the presence of a stenosis of the SMA. An incremental effect of the severity of the CA stenosis was found with a mean SMA PSV of 158 cm/s when normal and 259 cm/s when occluded. The presence of collaterals had a clear effect on duplex parameters of the angiographically normal SMA. In the presence of collaterals and a 70% CA stenosis, the PSV in the normal SMA was significantly higher (P = .025).

CONCLUSIONS

This study shows that stenosis in either the CA or SMA increases flow velocities in the other unaffected mesenteric artery. This increase was correlated with the presence of collaterals. Collaterals and stenoses in one of the mesenteric arteries may lead to mimicking or overgrading of stenosis in the other mesenteric artery.

[From CVA or TIA to carotid surgery: the clinical treatment course for patients with symptomatic carotid disease could be shorter]

OBJECTIVE

To gain insight into the duration and the various components of the clinical treatment course for patients with symptomatic carotid artery stenosis, in order to improve the care provided to these patients.

DESIGN

Retrospective cohort study.

METHODS

All patients who had undergone a carotid intervention for significant symptomatic carotid stenosis from 2001 to 2011 were included. Quantile regression analysis was used to assess the changes which had occurred in the median duration of the period from neurological event to intervention from 2001 onward. In order to chart the clinical treatment course, it was split up in different components. In addition, the impact of the referrer and the relationship between the time of the intervention and the risk of perioperative complications were also evaluated.

RESULTS

The median duration of the entire clinical treatment course decreased during the study period from 79 days (interquartile range (IQR): 59-113) in the reference period 2001-2004 to 19 days (IQR: 13-28) in 2011. All components of the clinical pathway had contributed to this decline. The duration of the clinical course in patients who had been externally referred was more than 3 times longer (median 67 vs. 21 days, p < 0.01). The total duration of the process did not affect the number of perioperative complications.

CONCLUSION

In the last decennium, the duration of the clinical treatment course of care in patients with symptomatic carotid artery disease was greatly reduced. Analyses of the processes which make up the chain of events, however, reveal that there is still much to be gained in the period before initial presentation at the hospital for patients who are referred by their general practitioners as well as those referred by other hospitals.

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 skin autofluorescence after colorectal operation reflects surgical stress and postoperative outcome

BACKGROUND

Abdominal surgery is a major oxidative stress effector. The increase in oxidative stress has been related to postoperative complications. Oxidative stress leads to the formation and accumulation of oxidation protein end products, which exhibit autofluorescence (AF) and induce inflammatory reactions.

METHODS

Skin AF was assessed perioperatively in 40 consecutive colorectal surgery patients until discharge. Duration of surgery, estimated blood loss, and urinary production per hour were analyzed as measures of surgical stress. The clinical occurrence of anastomotic leakage, systemic infections, and cardiopulmonary complications within 30 days of surgery were analyzed.

RESULTS

A perioperative increase in skin AF of 19 ± .2% was observed. Duration of operation and blood loss were independently associated with the perioperative increase in skin AF. Skin AF correlated with C-reactive protein levels postoperatively. American Society of Anesthesiologists classification, duration of operation, and preoperative and perioperative increases in AF were independently associated with postoperative complications.

CONCLUSIONS

This is the first study to demonstrate an association between skin AF and surgical stress and outcomes, which may rate the condition of a patient after operation.

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.

Skin autofluorescence is increased in patients with carotid artery stenosis and peripheral artery disease

Advanced glycation end products (AGEs) have a pivotal role in atherosclerosis. We evaluated skin autofluorescence (SAF), a non-invasive measurement of tissue AGE accumulation, in patients with carotid artery stenosis with and without coexisting peripheral artery occlusive disease (PAOD). SAF was measured using the AGE Reader™ in 56 patients with carotid artery stenosis and in 56 age- and sex-matched healthy controls without diabetes, renal dysfunction or known atherosclerotic disease. SAF was higher in patients with carotid artery stenosis compared to the control group: mean 2.81 versus 2.46 (P = 0.002), but especially in the younger age group of 50–60 years old: mean 2.82 versus 1.94 (P = 0.000). Patients with carotid artery stenosis and PAOD proved to have an even higher SAF than patients with carotid artery stenosis only: mean 3.28 versus 2.66 (P = 0.003). Backward linear regression analysis showed that age, smoking, diabetes mellitus, renal function and the presence of PAOD were the determinants of SAF, but carotid artery stenosis was not. SAF is increased in patients with carotid artery stenosis and PAOD. The univariate and multivariate associations of SAF with age, smoking, diabetes, renal insufficiency and PAOD suggest that increased SAF can be seen as an indicator of widespread atherosclerosis.

[Endarterectomy more favourable than stenting in symptomatic significant carotid stenosis: higher risk of ischaemic stroke or death following stenting]

Carotid endarterectomy (CEA) has proven its value in the treatment of patients with recent significant carotid artery stenosis. Percutaneous transluminal angioplasty with carotid artery stenting ('stenting' in short) is an alternative to CEA. The results of stenting and CEA in patients with symptomatic significant carotid artery stenosis were evaluated in 9 prospective randomized controlled trials and 11 meta-analyses. Almost all of these trials failed to show superiority of stenting to CEA. According to the 4 largest and most recent studies in this field the risk of a stroke or death within 30 days after the intervention is considerably higher following stenting than following CEA. In the long run the results of stenting and CEA seem to be comparable. CEA remains the gold standard in treatment of significant carotid artery stenosis, in particular in patients older than 70.

Carotid endarterectomy: current consensus and controversies

Stroke is the third most common cause of mortality, and carotid artery stenosis causes 8% to 29% of all ischemic strokes. Best medical treatment forms the basis of carotid stenosis treatment, and carotid endarterectomy (CEA) has an additional beneficial effect in high-grade stenosis. Carotid angioplasty and stenting (CAS) has challenged CEA as a primary carotid intervention. At present, CEA remains the gold standard, but in the future, CAS techniques will evolve and might become beneficial for subgroups of patients with carotid stenosis. This chapter briefly describes the history of carotid interventions and current consensus and controversies in CEA. In the last two years, several meta-analyses were published on a variety of aspects of best medical treatment, CEA, and CAS. It is still a matter of debate as to whether asymptomatic patients with carotid stenosis should undergo a carotid intervention. Especially because medical treatment has dramatically evolved since the early carotid trials. On the other hand, it is clear that carotid interventions in symptomatic patients with a high-grade stenosis should be performed as early as possible after the initial neurological event in order to achieve optimal stroke risk reduction. In CEA, the use of patching is advocated above primary closure, while the role of selective patching is still unclear. No differences in stroke and mortality rates are observed for routine versus selective shunting, for conventional versus eversion CEA, or for local versus general anesthesia. It is anticipated that in the future, there will be several interesting developments in carotid interventions such as plaque morphology analysis, acute interventions during stroke in progress, and further evolvement of CAS techniques.

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.

The clinical relevance of assessing advanced glycation endproducts accumulation in diabetes

Cardiovascular disease is the major cause of morbidity and mortality associated with diabetes. There is increasing evidence that advanced glycation endproducts (AGEs) play a pivotal role in atherosclerosis, in particular in diabetes. AGE accumulation is a measure of cumulative metabolic and oxidative stress, and may so represent the "metabolic memory". Furthermore, increased AGE accumulation is closely related to the development of cardiovascular complications in diabetes. This review article will focus on the clinical relevance of measuring AGE accumulation in diabetic patients by focusing on AGE formation, AGEs as predictors of long-term complications, and interventions against AGEs.

Endarterectomy or carotid artery stenting: the quest continues

BACKGROUND

Carotid endarterectomy (CEA) is still considered the "gold-standard" of the treatment of patients with significant carotid stenosis and has proven its value during past decades. However, endovascular techniques have recently been evolving. Carotid artery stenting (CAS) is challenging CEA for the best treatment in patients with carotid stenosis. This review presents the development of CAS according to early reports, results of recent randomized trials, and future perspectives regarding CAS.

METHODS

A literature search using the PubMed and Cochrane databases identified articles focusing on the key issues of CEA and CAS.

RESULTS

Early nonrandomized reports of CAS showed variable results, and the Stenting and Angioplasty With Protection in Patients at High Risk for Endarterectomy trial led to United States Food and Drug Administration approval of CAS for the treatment of patients with symptomatic carotid stenosis. In contrast, recent trials, such as the Stent-Protected Angioplasty Versus Carotid Endarterectomy trial and the Endarterectomy Versus Stenting in Patients with Symptomatic Severe Carotid Stenosis trial, (re)fuelled the debate between CAS and CEA. In the Stent-Protected Angioplasty Versus Carotid Endarterectomy trial, the complication rate of ipsilateral stroke or death at 30 days was 6.8% for CAS versus 6.3% for CEA and showed that CAS failed the noninferiority test. Analysis of the Endarterectomy Versus Stenting in Patients With Symptomatic Severe Carotid Stenosis trial showed a significant higher risk for death or any stroke at 30 days for endovascular treatment (9.6%) compared with CEA (3.9%). Other aspects-such as evolving best medical treatment, timely intervention, interventionalists' experience, and analysis of plaque composition-may have important influences on the future treatment of patients with carotid artery stenosis.

CONCLUSIONS

CAS performed with or without embolic-protection devices can be an effective treatment for patients with carotid artery stenosis. However, presently there is no evidence that CAS provides better results in the prevention of stroke compared with CEA.

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.

Skin autofluorescence is a strong predictor of cardiac mortality in diabetes

OBJECTIVE

Advanced glycation end products (AGEs) are biomarkers of metabolic stress and are thought to contribute to the increase of coronary heart disease (CHD) in diabetes. Tissue autofluorescence is related to the accumulation of AGEs. The aim of the present study was to evaluate the relationship between skin autofluorescence and metabolic burden (hyperglycemia and hyperlipidemia) and its relationship with CHD and mortality.

RESEARCH DESIGN AND METHODS

Skin autofluorescence was measured noninvasively with an autofluorescence reader in 48 type 1 and 69 type 2 diabetic patients and 43 control subjects. The presence of CHD was observed at baseline and mortality during a follow-up period of 5 years.

RESULTS

Autofluorescence correlated with mean A1C, triglycerides, and LDL. Autofluorescence values further increased with age, microalbuminuria, dialysis treatment, and diabetes duration. Autofluorescence was strongly related to the presence of CHD (odds ratio 7.9) and predicted mortality (3.0). Multivariate analysis showed that autofluorescence was more strongly associated with CHD and mortality compared with A1C, triglycerides, and LDL.

CONCLUSIONS

Skin autofluorescence is strongly related to cumulative metabolic burden. Skin autofluorescence seems strongly associated with cardiac mortality and may provide important clinical information for risk assessment.

Accumulation of Advanced Glycation End Products, Measured as Skin Autofluorescence, in Renal Disease

Advanced glycation end products (AGEs) accumulate during renal failure and dialysis. Kidney transplantation is thought to reverse this accumulation by restoring renal function. Using a noninvasive and validated autofluorescence reader, we evaluated AGE levels in 285 transplant recipients (mean age, 52 years; range, 41 to 60 years), 32 dialysis patients (mean age, 56 years; range, 43 to 65 years), and 231 normal control subjects (mean age, 51 years; range, 40 to 65 years). Measurements in transplant recipients were performed for a mean of 73 months (range, 32 to 143 months) after transplantation. Dialysis patients were on dialysis therapy for a mean of 42 months (range, 17 to 107 months). Fluorescence was significantly increased in dialysis patients compared with normal control subjects (2.8 vs. 2.0 arbitrary units [a.u.], P < .0001). Although fluorescence levels were significantly decreased in transplant recipients compared with dialysis patients (2.5 vs. 2.8 a.u., P < .0001), fluorescence in transplant recipients was higher than in controls (2.5 vs. 2.0 a.u., P < .0001). In transplant recipients, fluorescence correlated positively with the duration of dialysis prior to transplantation (R = 0.21, P < .0001), and negatively with creatinine clearance (R = -0.34, P < .0001). No correlation was found between time after transplantation and fluorescence in transplant recipients (R = -0.10, P = .10). Fluorescence in dialysis patients was positively correlated with duration of dialysis (R = 0.36, P = .042). Our results, like those of others, suggest that kidney transplantation does not fully correct increased AGE levels found in dialysis patients. The increased AGE levels in kidney transplant recipients cannot be explained by the differences in renal function alone. The availability of a simple, noninvasive method (AGE-Reader) to measure AGE accumulation may be used to monitor AGE accumulation in a clinical setting as well as in a study setting.

Skin autofluorescence, a measure of cumulative metabolic stress and advanced glycation end products, predicts mortality in hemodialysis patients

Tissue advanced glycation end products (AGE) are a measure of cumulative metabolic stress and trigger cytokines driven inflammatory reactions. AGE are thought to contribute to the chronic complications of diabetes and ESRD. Tissue autofluorescence is related to the accumulation of AGE. Therefore, skin autofluorescence (AF) may provide prognostic information on mortality in hemodialysis (HD) patients. Skin AF was measured noninvasively with an AF reader at baseline in 109 HD patients. Overall and cardiovascular mortality was monitored prospectively during a period of 3 yr. The AF reader was validated against AGE contents in skin biopsies from 29 dialysis patients. Forty-two of the 109 (38.5%) HD patients died. Cox regression analysis showed that AF was an independent predictor of overall and cardiovascular mortality (for overall mortality odds ratio [OR] 3.9), as were pre-existing cardiovascular disease (CVD; OR 3.1), C-reactive protein (OR 1.1), and serum albumin (OR 0.3). Multivariate analysis revealed that 65% of the variance in AF could be attributed to the independent effects of age, dialysis and renal failure duration, presence of diabetes, triglycerides levels, and C-reactive protein. AF was also independently linked to the presence of CVD at baseline (OR 8.8; P < 0.001). AF correlated with collagen-linked fluorescence (r = 0.71, P < 0.001), pentosidine (r = 0.75, P < 0.001), and carboxy(m)ethyllysine (both r = 0.45, P < 0.01). Skin AF is a strong and independent predictor of mortality in ESRD. This supports a role for AGE as a contributor to mortality and CVD and warrants interventions specifically aimed at AGE accumulation.

Simple noninvasive measurement of skin autofluorescence

Accumulation of advanced glycation end products (AGEs) is thought to play a role in the pathogenesis of chronic complications of diabetes mellitus and renal failure. Several studies indicate that AGE accumulation in tissue may reflect the cumulative effect of hyperglycemia and oxidative stress over many years. Simple quantitation of AGE accumulation in tissue could provide a tool for assessing the risk of long-term complications. Because several AGEs exhibit autofluorescence, we developed a noninvasive autofluorescence reader (AFR). Skin autofluorescence measured with the AFR correlates with collagen-linked fluorescence and specific skin AGE levels from skin biopsy samples. Furthermore, skin autofluorescence correlates with long-term glycemic control and renal function, and preliminary results show correlations with the presence of long-term complications in diabetes. The AFR may be useful as a clinical tool for rapid assessment of risk for AGE-related long-term complications in diabetes and in other conditions associated with AGE accumulation.

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.

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</=0.002). In 32 of 46 diabetic patients (70%), autofluorescence values were above the 95% CI of the mean value in control subjects, and correlated with age, diabetes duration, mean HbA(1)c of the previous year and creatinine levels.

CONCLUSIONS/INTERPRETATION

The AFR offers a simple alternative to invasive measurement of AGE accumulation and, to date, has been validated in non-pigmented skin. The AFR may prove to be a useful clinical tool for rapid risk assessment of AGE-related long-term complications in diabetes mellitus and in other conditions associated with AGE accumulation.

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.

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.