Clark Zeebregts | University Medical Center Groningen (original) (raw)

Papers by Clark Zeebregts

American journal of surgery, Jan 7, 2015

To date, the incidence and clinical relevance of arterial stenosis at clamp sites after femoropop... more To date, the incidence and clinical relevance of arterial stenosis at clamp sites after femoropopliteal bypass surgery is unknown. Ninety-four patients underwent a femoropopliteal bypass in which the arterial inflow and outflow clamp sites were controlled by the Fogarty-Soft-Inlay clamp and marked with an hemoclip. The number of pre-existing atherosclerotic segments, clamp force, and clamp time were recorded and the occurrence of a stenosis at the clamp site was determined. After a mean follow-up of 83 months, a significant stenosis was confirmed at 23 of the 178 clamp sites (12.9%; 95% confidence interval 8.4 to 18.8). The mean number of pre-existing atherosclerotic segments (P = .28) and the mean clamp force (P = .55) was similar between the groups with and without a stenosis. There was a significant difference regarding clamp time between the group with and without a stenosis (38 minutes and 26 minutes, P = .001). Arterial clamping, even with the Fogarty-Soft-Inlay clamp, can lea...

Cardiovascular research, Jan 26, 2015

Cardiovascular disease (CVD) is the leading cause of death in patients with chronic kidney diseas... more Cardiovascular disease (CVD) is the leading cause of death in patients with chronic kidney disease (CKD), a disease state that is strongly associated with loss of renal and systemic (alpha-)Klotho. Reversely, murine Klotho deficiency causes marked medial calcification. It is therefore thought that Klotho conveys a vasculoprotective effect. Klotho expression in the vessel wall, however, is disputed. We assessed Klotho expression in healthy human renal donor arteries (N=9), CKD (renal graft recipient) arteries (N=10), carotid endarterectomy specimens (N=8), other elastic arteries (3 groups of N=3), and cultured human aortic smooth muscle cells (HASMCs) (3 primary cell lines), using immunohistochemistry (IHC), immunofluorescence, qRT-PCR, and Western blotting (WB). We have extensively validated anti-Klotho antibody KM2076 by comparing staining patterns to other anti-Klotho antibodies (SC-22220, SC-22218, and AF1819), competition assays with recombinant Klotho, IHC on Klotho-deficient k...

Surgical technology international, 2015

In the last decade, minimally invasive endothermal ablation techniques have replaced surgery for ... more In the last decade, minimally invasive endothermal ablation techniques have replaced surgery for the treatment of superficial venous insufficiency to reduce postoperative complications and recovery time and to improve quality of life. To avoid the risks of nerve damage and need for tumescent anesthesia to improve patient comfort, an alternative heatless technique has been introduced recently. Endovenous mechanochemical occlusion using the ClariVein® catheter (Vascular Insights LLC, Quincy, MA) is a new technique combining mechanical injury to the venous endothelium coupled with simultaneous catheter-guided infusion of a liquid sclerosant. This produces irreversible damage to the endothelium resulting in fibrosis of the vein. The technique is related to a low complication rate and a success rate of 96% at two years and sustained quality of life improvement. This closure rate is comparable to endothermal techniques, but significantly less postoperative pain and earlier return to norma...

Medical Hypotheses, 2015

Appropriate sizing of endografts for endovascular aneurysm repair has traditionally been performe... more Appropriate sizing of endografts for endovascular aneurysm repair has traditionally been performed by one standardized method. By measuring the average of the minor and major axes in the sealing zone, the endograft size is traditionally calculated. However, no adequate scientific evaluation has been performed to validate this method. The guidelines that were published are based on theories and experience, more than scientific evidence. In case the central lumen line artery cross-section is a circular disk, the vessel diameter is a reliable estimation. Yet the aortic neck cross-section may not always be geometrically a perfect circular disk. Application of the standardized method might therefore lead to inaccurate endograft sizing, potentially leading to endoleaks. We hypothesize that in these cases the circumference of the vessel is a mathematically correct reference to deduct the appropriate endograft diameter. The following formula was applied in this study: diameter of the corresponding circle (d) equals circumference (C) divided by πd=Cπ. This study provides a theoretical analysis of the mathematical implications of this method. Only in case of highly irregularly shaped cylinders, the circumference-based method was more accurate than the standardized method. Nonetheless, the circumferential method was a practical reference in case the aortic neck was irregularly shaped. Also, the circumference method was accurate in all cases in deducting the diameter of a matching circle. Therefore, the hypothesis that was raised in this study has a strong theoretical base. We predict that in case this hypothesis holds true in the clinical practice, application of the circumference method might lead to less endoleaks than the standardized method.

Arteriosclerosis, thrombosis, and vascular biology, Jan 16, 2015

Patients with peripheral artery disease are at risk for critical limb ischemia and amputation. Ac... more Patients with peripheral artery disease are at risk for critical limb ischemia and amputation. Accumulation of advanced glycation end products is increased and predictive for coronary and cerebrovascular events in several high cardiovascular risk groups. We hypothesized that accumulation of tissue advanced glycation end products, measured by skin autofluorescence (SAF), predicts amputation in patients with peripheral artery disease. Between October 2007 and June 2008, 252 patients with peripheral artery disease were included at the outpatient clinic. During a 5-year follow-up, 22 (9%) had an amputation because of critical limb ischemia. Competing risk analysis showed a subproportional hazard ratio of 3.05 (95% confidence interval [CI], 1.87-4.96); P<0.0001 for amputation per unit of SAF. After correction for diabetes mellitus and Fontaine stage, subproportional hazard ratio was 2.72 (95% CI, 1.38-5.39); P=0.004. In patients with Fontaine stage I and II only (n=215), SAF was the o...

Journal of vascular surgery, Jan 6, 2015

The objective of this study was to determine the incidence of and specific preoperative and intra... more The objective of this study was to determine the incidence of and specific preoperative and intraoperative risk factors for postoperative delirium (POD) in electively treated vascular surgery patients. Between March 2010 and November 2013, all vascular surgery patients were included in a prospective database. Various preoperative, intraoperative, and postoperative risk factors were collected during hospitalization. The primary outcome variable was the incidence of POD. Secondary outcome variables were any surgical complication, hospital length of stay, and mortality. In total, 566 patients were prospectively evaluated; 463 patients were 60 years or older at the time of surgery and formed our study cohort. The median age was 72 years (interquartile range, 66-77), and 76.9% were male. Twenty-two patients (4.8%) developed POD. Factors that differed significantly by univariate analysis included current smoking (P = .001), increased comorbidity (P = .001), hypertension (P = .003), diabet...

BioMed research international, 2014

Vascular prosthetic graft infection (VPGI) is a severe complication after vascular surgery. CT-sc... more Vascular prosthetic graft infection (VPGI) is a severe complication after vascular surgery. CT-scan is considered the diagnostic tool of choice in advanced VPGI. The incidence of a false-negative result using CT is relatively high, especially in the presence of low-grade infections. (18)F-fluorodeoxyglucose positron emission tomography ((18)F-FDG PET) scanning has been suggested as an alternative for the diagnosis and assessment of infectious processes. Hybrid (18)F-FDG PET/CT has established the role of (18)F-FDG PET for the assessment of suspected VPGI, providing accurate anatomic localization of the site of infection. However, there are no clear guidelines for the interpretation of the uptake patterns of (18)F-FDG as clinical tool for VPGI. Based on the available literature it is suggested that a linear, diffuse, and homogeneous uptake should not be regarded as an infection whereas focal or heterogeneous uptake with a projection over the vessel on CT is highly suggestive of infec...

Annals of vascular surgery, 2014

The etiology of postoperative delirium (POD) following vascular surgery is generally unknown. The... more The etiology of postoperative delirium (POD) following vascular surgery is generally unknown. The incidence, however, can be as high as 35%. A possible neuroinflammatory basis for delirium is likely and C-reactive protein (CRP) as a marker for inflammation can possibly play a predictive role. Between March 2010 and September 2012, 277 consecutive elective vascular surgery patients were prospectively evaluated for the diagnosis of POD. Various potential risk factors, including postoperative CRP values, were collected. The mean age of the patients was 69 ± 11 years (range 21-92). The mean hospital length of stay was 6 ± 4 days (range 1-33). Sixteen patients (6%) developed POD during hospital stay. Univariate analysis revealed multiple comorbidities (P = 0.001), postoperative elevated CRP levels (P = 0.001), intensive care unit admittance (P = 0.01), and open aortic surgery or amputation procedures (P = 0.0001) to be significantly related to the diagnosis POD. Multivariate logistic reg...

American journal of surgery, 2004

The European journal of surgery = Acta chirurgica, 2002

To evaluate patency rates of Brescia-Cimino fistulas and to find out which independent factors we... more To evaluate patency rates of Brescia-Cimino fistulas and to find out which independent factors were predictors of failure. Retrospective clinical study. University hospital, The Netherlands. 150 consecutive patients (mean age 56 years, range 17-80) who had 153 primary Brescia-Cimino fistulas created during the 5-year period January 1995-December 1999. Patency rates calculated by the Kaplan-Meier method and the possible predictive value of 20 different variables assessed by Cox's proportional hazard model. The primary patency rate was 70% at 3 months, and 7 distinct factors were significantly associated with failure of the fistula. The ones with a hazard ratio (HR) for failure greater than 2.5 were: the start of dialysis before creation of the fistula (HR 2.79, p < 0.01), moderate or poor quality of both the artery (HR 2.54, p < 0.01) and vein (HR 3.55, p < 0.001), and postoperative use of acenocoumarol instead of acetylsalicylic acid (HR 3.14. p < 0.01). The major de...

Seminars in Vascular Surgery, 2015

Lower-limb venous insufficiency resulting from saphenous vein incompetence is a common disorder, ... more Lower-limb venous insufficiency resulting from saphenous vein incompetence is a common disorder, increasing with age. For decades, surgical stripping of the great saphenous vein has been the gold standard in varicose vein treatment. The desire to optimize outcomes of treatment and reduce surgical trauma has led to the development of endovenous techniques. Today, several endovenous techniques are available to ablate the saphenous vein segments with abnormal vein valve function. In this review, we discuss the techniques, mechanisms of action, outcomes, and complications of all endovenous treatment modalities for the treatment of symptomatic lower-limb varicose veins.

Plastic and Reconstructive Surgery, 2010

The authors conducted a review of the recent literature on the monitoring of free flaps to create... more The authors conducted a review of the recent literature on the monitoring of free flaps to create an overview of the current monitoring devices and their potential as an ideal monitoring method. A literature-based study was conducted using the PubMed and Cochrane databases. The following search terms were used: &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot;flap&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot; and &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot;monitoring.&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot; All monitoring methods found between January of 1999 and January of 2009 were evaluated. Monitoring methods that were described in five or more clinical reports were further investigated. The advantages and disadvantages of conventional monitoring methods, the implantable Doppler system, color duplex sonography, near-infrared spectroscopy, microdialysis, and laser Doppler flowmetry are presented. Furthermore, an overview is given of their potential as ideal monitoring method. The implantable Doppler system, near-infrared spectroscopy, and laser Doppler flowmetry appear to be the best monitoring devices currently available. As most of the publications on monitoring have focused on the reliability of the systems, future research should also address their cost efficiency.

Emergency Radiology, 2008

The aim of the study was to describe the successful endovascular management of a patient who was ... more The aim of the study was to describe the successful endovascular management of a patient who was admitted urgently with a second episode of acute abdominal aortic aneurysm (AAA) 30 months after emergency endovascular abdominal aortic aneurysm repair (eEVAR) for a ruptured AAA. The patient, an 84 year-old male physician, presented with severe acute abdominal and back pain. Contrast-enhanced computer tomography scanning showed type III endoleak owing to complete disconnection of both graft limbs and the prosthetic main body. Treatment consisted of acute stent-grafting with two bridging stent-grafts to seal the endoleak and reline the graft. The patient is alive and well 6 months postoperatively. This case indicates the need for follow-up after eEVAR, but also that complications can be managed endovascularly.

The American Journal of Surgery, 2014

Vascular, 2014

Complex iliac anatomy including extreme tortuosity constitutes a relative contraindication for en... more Complex iliac anatomy including extreme tortuosity constitutes a relative contraindication for endovascular abdominal aortic aneurysm repair with additional risk of limb-graft occlusion. The Gore Excluder limb-graft is a flexible stent-graft, which adapts easily to iliac tortuosity. Nevertheless, the presence of the stiff guide wire does not always allow for an ideal apposition of the stent graft to the angulated common iliac artery vessel wall. We describe herein a modified technique for Gore Excluder limb-graft deployment with partial removal of the stiff wire in cases with difficult tortuous or narrow iliac arteries during endovascular abdominal aortic aneurysm repair.

The American Journal of Surgery, 2011

Abdominal surgery is a major oxidative stress effector. The increase in oxidative stress has been... more 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. 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. 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. 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.