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Background: Incidence of central venous catheter (CVC)-related thrombosis in critically ill patients remains ambiguous and its association with potential hazardous sequelae unknown. The primary aim of the study was to evaluate the epidemiology of CVC-related thrombosis; secondary aims were to assess the association of catheter-related thrombosis with catheter-related infection, pulmonary embolism and mortality., Methods: This was a single-center, prospective observational study conducted at a tertiary intensive care unit (ICU) in the Netherlands. The study population consisted of CVC placements in adult ICU patients with a minimal indwelling time of 48 h. CVC-related thrombosis was diagnosed with ultrasonography. Primary outcomes were prevalence and incidence, incidence was reported as the number of cases per 1000 indwelling days., Results: 173 CVCs in 147 patients were included. Median age of patients was 64.0 [IQR: 52.0, 72.0] and 71.1 % were male. Prevalence of thrombosis was 0.56 (95 % CI: 0.49, 0.63) and incidence per 1000 indwelling days was 65.7 (95 % CI: 59.0, 72.3). No association with catheter-related infection was found (p = 0.566). There was a significant association with pulmonary embolism (p = 0.022). All 173 CVCs were included in the survival analysis. Catheter-related thrombosis was associated with a lower 28-day mortality risk (hazard ratio: 0.39, 95 % CI: 0.17, 0.87)., Conclusion: In critically ill patients, prevalence and incidence of catheter-related thrombosis were high. Catheter-related thrombosis was not associated with catheter-related infections, but was associated with pulmonary embolism and a decreased mortality risk., Competing Interests: Declaration of competing interest The authors declare that they have no competing interests., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Rationale: Antiplatelet therapy (APT) is the standard of care after endovascular revascularization (EVR) in patients with peripheral artery disease (PAD). APT aims to prevent both major adverse cardiovascular events (MACE) and major adverse limb events (MALE). Nonetheless, the rates of MACE and MALE after EVR remain high. In coronary artery and cerebrovascular disease, dual APT (DAPT)compared to acetylsalicylic acid alone has been proven to reduce MACE without increasing the risk of major bleeding when applied for a restricted number of weeks. However, within the PAD population, insufficient data are available to understand the potential attributable effect of DAPT over single APT (SAPT). Therefore, prospective randomized studies in targeted study populations are warranted., Trial Design: CLEAR-PATH is a Dutch multicenter, double-blind, placebo-controlled, randomized trial comparing SAPT (clopidogrel 75 mg plus placebo) with DAPT (clopidogrel 75 mg plus acetylsalicylic acid 80 mg) in patients with PAD undergoing EVR. CLEAR-PATH includes a time-to-event analysis with a follow-up of one year. The primary composite efficacy endpoint consists of all-cause mortality, nonfatal stroke, nonfatal myocardial infarction, severe limb ischemia, (indication for) re-intervention due to any symptomatic restenosis, re-occlusion, or due to acute limb ischemia, and major amputation. The primary safety endpoint contains major bleeding following the Thrombolysis in Myocardial Infarction classification. The enrolment started in August 2022. In total 450 primary efficacy outcome events are required which expectedly amounts to 1696 subjects. Recruitment will take approximately 36 months., Conclusion: CLEAR-PATH will assess the efficacy and safety of DAPT compared to SAPT following EVR in PAD patients., Trial Registration Number: NL80009.041.21., Competing Interests: Conflict of interest The CLEAR-PATH study is made possible by ZonMw (dossier number: 80-84800-98-44023) which is an independent grant provider. The authors have no (potential) conflict of interest., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

Background and Objectives: Vaccine-induced thrombotic thrombocytopenia (VITT) is a rare adverse effect characterized by thrombocytopenia and thrombosis occurring after COVID-19 vaccination. VITT pathophysiology is not fully unravelled but shows similarities to heparin-induced thrombocytopenia (HIT). HIT is characterized by the presence of antibodies against platelet factor 4 (PF4)/heparin complex, which can activate platelets in an FcγRIIa-dependent manner, whereas IgG-antibodies directed against PF4 play an important role in VITT., Materials and Methods: We characterized all clinically suspected VITT cases in the Netherlands from a diagnostic perspective and hypothesized that patients who developed both thrombocytopenia and thrombosis display underlying mechanisms similar to those in HIT. We conducted an anti-PF4 ELISA and a functional PF4-induced platelet activation assay (PIPAA) with and without blocking the platelet-FcγRIIa and found positivity in both tests, suggesting VITT with mechanisms similar to those in VITT., Results: We identified 65 patients with both thrombocytopenia and thrombosis among 275 clinically suspected VITT cases. Of these 65 patients, 14 (22%) tested positive for anti-PF4 and PF4-dependent platelet activation. The essential role of platelet-FcγRIIa in VITT with mechanisms similar to those in HIT was evident, as platelet activation was inhibited by an FcγRIIa-blocking antibody in all 14 patients., Conclusion: Our study shows that only a small proportion of clinically suspected VITT patients with thrombocytopenia and thrombosis have anti-PF4-inducing, FcɣRIIa-dependent platelet activation, suggesting an HIT-like pathophysiology. This leaves the possibility for the presence of another type of pathophysiology ('non-HIT like') leading to VITT. More research on pathophysiology is warranted to improve the diagnostic algorithm and to identify novel therapeutic and preventive strategies., (© 2024 International Society of Blood Transfusion.)

Introduction: In the first wave, thrombotic complications were common in COVID-19 patients. It is unknown whether state-of-the-art treatment has resulted in less thrombotic complications in the second wave., Methods: We assessed the incidence of thrombotic complications and overall mortality in COVID-19 patients admitted to eight Dutch hospitals between September 1st and November 30th 2020. Follow-up ended at discharge, transfer to another hospital, when they died, or on November 30th 2020, whichever came first. Cumulative incidences were estimated, adjusted for competing risk of death. These were compared to those observed in 579 patients admitted in the first wave, between February 24th and April 26th 2020, by means of Cox regression techniques adjusted for age, sex and weight., Results: In total 947 patients with COVID-19 were included in this analysis, of whom 358 patients were admitted to the ICU; 144 patients died (15%). The adjusted cumulative incidence of all thrombotic complications after 10, 20 and 30 days was 12% (95% confidence interval (CI) 9.8-15%), 16% (13-19%) and 21% (17-25%), respectively. Patient characteristics between the first and second wave were comparable. The adjusted hazard ratio (HR) for overall mortality in the second wave versus the first wave was 0.53 (95%CI 0.41-0.70). The adjusted HR for any thrombotic complication in the second versus the first wave was 0.89 (95%CI 0.65-1.2)., Conclusions: Mortality was reduced by 47% in the second wave, but the thrombotic complication rate remained high, and comparable to the first wave. Careful attention to provision of adequate thromboprophylaxis is invariably warranted., (Copyright © 2021 The Author. Published by Elsevier Ltd.. All rights reserved.)

Background:  Hepatic artery thrombosis (HAT) and portal vein thrombosis (PVT) are serious causes of morbidity and mortality after pediatric liver transplantation. To reduce thrombotic complications, routine antithrombotic therapy consisting of 1 week heparin followed by 3 months acetylsalicylic acid, was implemented in our pediatric liver transplant program in 2003. This study aimed to evaluate incidences of bleeding and thrombotic complications since the implementation of routine antithrombotic therapy and to identify risk factors for these complications., Methods:  This retrospective cohort study includes 200 consecutive pediatric primary liver transplantations performed between 2003 and 2016. Uni- and multivariate logistic regression analysis, Kaplan-Meier method, and Cox regression analysis were used to evaluate recipient outcome., Results:  HAT occurred in 15 (7.5%), PVT in 4 (2.0%), and venous outflow tract thrombosis in 2 (1.0%) recipients. Intraoperative vascular interventions (odds ratio [OR] 14.45 [95% confidence interval [CI] 3.75-55.67]), low recipient age (OR 0.81 [0.69-0.95]), and donor age (OR 0.96 [0.93-0.99]) were associated with posttransplant thrombosis. Clinically relevant bleeding occurred in 37%. Risk factors were high recipient age (OR 1.08 [1.02-1.15]), high Child-Pugh scores (OR 1.14 [1.02-1.28]), and intraoperative blood loss in mL/kg (OR 1.003 [1.001-1.006]). Both posttransplant thrombotic (hazard ratio [HR] 3.38 [1.36-8.45]; p  = 0.009) and bleeding complications (HR 2.50 [1.19-5.24]; p  = 0.015) significantly increased mortality., Conclusion:  In 200 consecutive pediatric liver transplant recipients receiving routine postoperative antithrombotic therapy, we report low incidences of posttransplant vascular complications. Posttransplant antithrombotic therapy seems to be a valuable strategy in pediatric liver transplantation. Identified risk factors for bleeding and thrombotic complications might facilitate a more personalized approach in antithrombotic therapy., Competing Interests: None declared., (Georg Thieme Verlag KG Stuttgart · New York.)

Background and Purpose: Carotid webs are increasingly recognized as an important cause of (recurrent) ischemic stroke in patients without other cardiovascular risk factors. Hemodynamic flow patterns induced by these lesions might be associated with thrombus formation. The aim of our study was to evaluate flow patterns of carotid webs using computational fluid dynamics., Materials and Methods: Patients with a carotid web in the Multicenter Randomized Clinical Trial of Endovascular Treatment of Acute Ischemic Stroke in the Netherlands (MR CLEAN) were selected for hemodynamic evaluation with computational fluid dynamics models based on lumen segmentations obtained from CT angiography scans. Hemodynamic parameters, including the area of recirculation zone, time-averaged wall shear stress, transverse wall shear stress, and the oscillatory shear index, were assessed and compared with the contralateral carotid bifurcation., Results: In our study, 9 patients were evaluated. Distal to the carotid webs, recirculation zones were significantly larger compared with the contralateral bifurcation (63 versus 43 mm 2 , P = .02). In the recirculation zones of the carotid webs and the contralateral carotid bifurcation, time-averaged wall shear stress values were comparable (both: median, 0.27 Pa; P = .30), while transverse wall shear stress and oscillatory shear index values were significantly higher in the recirculation zone of carotid webs (median, 0.25 versus 0.21 Pa; P = .02 and 0.39 versus 0.30 Pa; P = .04). At the minimal lumen area, simulations showed a significantly higher time-averaged wall shear stress in the web compared with the contralateral bifurcation (median, 0.58 versus 0.45 Pa; P = .01)., Conclusions: Carotid webs are associated with increased recirculation zones and regional increased wall shear stress metrics that are associated with disturbed flow. These findings suggest that a carotid web might stimulate thrombus formation, which increases the risk of acute ischemic stroke., (© 2019 by American Journal of Neuroradiology.)

Objectives: This study sought to report the 5-year outcomes of everolimus-eluting stents (EES) and paclitaxel-eluting stents (PES) in an all-comers population undergoing percutaneous coronary intervention (PCI)., Background: The medium-term 1 and 2-year results of the prospective randomized COMPARE trial (A Trial of Everolimus-Eluting Stents and Paclitaxel-Eluting Stents for Coronary Revascularization in Daily Practice) showed superior clinical outcomes with EES compared with PES in an all-comers PCI population. Whether this benefit is sustained over longer-term follow-up is unknown. Furthermore, systematic long-term follow-up data on these metallic drug eluting stents with durable polymers are scarce., Methods: We randomly assigned 1,800 patients undergoing PCI to EES or PES. The pre-specified composite primary endpoint was death, myocardial infarction (MI), or target vessel revascularization (TVR)., Results: Follow-up at 5 years was completed in 1,791 (99.5%) patients. Treatment with EES compared with PES led to a relative risk reduction of the primary endpoint by 27% (18.4% vs. 25.1%, p = 0.0005), driven by lower rates of MI (7.0% vs. 11.5%, p = 0.001) and TVR (7.4% vs. 11.4%, p = 0.003), but not with mortality (9.0% vs. 10.3%, relative risk 0.88, p = 0.36). Moreover, patients treated with EES compared with PES had lower rates of definite/probable stent thrombosis at 5 years (3.1% vs. 5.9%, p = 0.005). The hazard curves for TVR, MI, and stent thrombosis diverge over the first 3 years and, subsequently, progress in parallel., Conclusions: The early- and medium-term superiority of EES over PES measured both by safety and efficacy endpoints is sustained at 5 years in this all-comer population. (A Trial of Everolimus-Eluting Stents and Paclitaxel-Eluting Stents for Coronary Revascularization in Daily Practice [COMPARE]; NCT01016041)., (Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Aim: The aim of this study was to evaluate the current practice of the use of perioperative antithrombotic drugs to prevent arterial thrombo-embolic complications during arterial vascular surgery by Dutch vascular surgeons. Aim was also to compare the results with the literature and to evaluate the effect of guidelines., Methods: A comprehensive questionnaire was sent to all Dutch vascular surgeons performing arterial reconstructive surgery., Results: The response rate was 84%. Acetylsalicylic acid (ASA) was continued perioperatively by most surgeons (91%). Clopidogrel was discontinued by the majority of respondents (65%). During operation 97% of surgeons administered unfractionated heparin (UFH) before arterial clamping. A minority (11%) measures peroperatively anticoagulant activity in patients' blood. After infrainguinal venous bypass most surgeons (81%) preferred monotherapy with vitamin K antagonists (VKA), in agreement with the Dutch guideline in this respect. Before the introduction of the guideline in 2005, a survey was performed in 2004. Results of our 2011 survey showed more respondents (6% to 11%) prescribed ASA or VKA according to these guidelines., Conclusion: This survey showed a recognizable pattern of variation for perioperative arterial thrombosis prophylaxis amongst Dutch vascular surgeons, in agreement with reports from other countries over the past 20 years. Although a higher percentage of surgeons complied in 2011 with existing guidelines than in 2004, guidelines were not completely met. Possibly because current guidelines are not fully supported by evidence and do not cover all aspects of perioperative arterial thrombosis prophylaxis. Clearly there is need for (more) convincing data based on RCT's concerning the various aspects of perioperative arterial thrombosis prophylaxis.

Introduction: Atrial arrhythmias are associated to thromboembolism and anticoagulant treatment is installed according to risk profile. This study aimed to assess the rate of thrombotic events and major bleedings in adults with congenital heart disease (CHD) and atrial arrhythmias, as well as to determine the predictive value of specific clinical features and two risk scores for thromboembolism and bleeding., Methods and Results: In this retrospective study, a total of 229 adult CHD patients with atrial arrhythmias, were included. Incidence and risk factors of thromboembolism were assessed in patients without a mechanical valve (n = 191), whereas bleeding incidence and risk factors were studied in patients receiving vitamin K antagonists (n = 164). In 13 patients without a mechanical valve thrombotic events occurred, the first thrombotic event rate per year being 1.4%. A total of 29 patients on vitamin K antagonists suffered from major bleedings, at an annual first event rate of 4.4%. CHA2DS2-VASc score and HAS-BLED score predicted thromboembolic and bleeding risk best in a dichotomized form. At a cut-off of ≥ 2 for high risk the rate of thrombotic events was 3.0% per year compared to 0.7% for a score of <2 (HR 3.7; 95%-CI 1.2-11.5; p = 0.021). A major bleeding rate of 10.8% per year was found in patients on vitamin K antagonists for HAS-BLED ≥ 2 as opposed to 3.5% with a score of <2 (HR 2.6; 95%-CI: 1.1-6.6; 0.017)., Conclusion: In adult CHD patients, thrombotic events and major bleedings are important complications of atrial arrhythmias and anticoagulant treatment. Assessment of thromboembolic and bleeding risk in this patients group can be performed with dichotomized CHA2DS2-VASc and HAS-BLED scores respectively., (Copyright © 2015. Published by Elsevier Ireland Ltd.)

Purpose: In the Netherlands, 86% of patients start renal replacement therapy with chronic intermittent hemodialysis (HD). Guidelines do indicate predialysis care and maintenance of a well-functioning vascular access (VA) as critical issues in the management of the renal failure patient. Referral to the surgeon and time to VA creation are important determinants of the type and success of the VA and HD treatment., Methods and Results: Data from a national questionnaire showed that time from referral to the surgeon and actual access creation is <4 weeks in 43%, 4 to 8 weeks in 30% and >8 weeks in 27% of the centers. Preoperative ultrasonography and postoperative access flowmetry are the diagnostic methods in the majority of centers (98%). Most facilities perform rope-ladder cannulation with occasionally the buttonhole technique for selected patients in 87% of the dialysis units. Endovascular intervention for thrombosis is practiced by 13%, surgical thrombectomy by 21% and either endovascular or surgery by 66% of the centers. Weekly multidisciplinary meetings are organized in 57% of the units. Central vein catheters are inserted by radiologists (36%), nephrologists and surgeons (32%)., Conclusions: We conclude that guidelines implementation has been successful in particular regarding issues as preoperative patient assessment for VA creation and postoperative surveillance in combination with (preemptive) endovascular intervention, leading to very acceptable VA thrombosis rates.

Aim: The aim of this paper was to review technical success and clinical outcome of reinterventions to treat complications after endovascular abdominal aortic aneurysm (AAA) repair (EVAR) in a tertiary vascular center., Methods: The study enrolled 107 patients treated for post-EVAR complications between January 2005 and March 2014. Details of reinterventions, technical success, and midterm clinical outcome were analyzed for reinterventions. Radiologic follow-up after reinterventions was performed by computed tomography scans and duplex ultrasonography., Results: Indications for reinterventions in the 107 patients were predominantly endoleaks type Ia, Ib, II, and III (55.1%). Endograft obstructions were observed in 39 patients (36.4%). The initial technical success rate for the 107 reinterventions was 93.5% (N.=100). Median follow-up postreintervention was 20 months (range, 1-107 months). During follow-up, 34 of 107 patients (31.8%) needed at least one renewed reintervention. Kaplan-Meier analysis of overall survival after the primary reinterventions was 85% at 1 year, and 78% at 3 years of follow-up. AAA/EVAR-associated mortality was 4% at 3 years. Kaplan-Meier survival estimation of freedom of recurrence was 88% at 1 year post-reintervention and 78% at 3 years. Renewed reintervention-free survival dropped to 78% at 1 year and 58% at 3 years., Conclusion: In this series of patients, the technical success rate of reinterventions to treat post-EVAR complications was high. During a median follow-up of 20 months, AAA-associated mortality is low, but the need for renewed (endovascular) reinterventions is substantial.

Introduction: Because of ongoing controversy, renal and vital outcomes are compared between systemically administered unfractionated heparin and regional anticoagulation with citrate-buffered replacement solution in predilution mode, during continuous venovenous hemofiltration (CVVH) in critically ill patients with acute kidney injury (AKI)., Methods: In this multi-center randomized controlled trial, patients admitted to the intensive care unit requiring CVVH and meeting inclusion criteria, were randomly assigned to citrate or heparin. Primary endpoints were mortality and renal outcome in intention-to-treat analysis. Secondary endpoints were safety and efficacy. Safety was defined as absence of any adverse event necessitating discontinuation of the assigned anticoagulant. For efficacy, among other parameters, survival times of the first hemofilter were studied., Results: Of the 139 patients enrolled, 66 were randomized to citrate and 73 to heparin. Mortality rates at 28 and 90 days did not differ between groups: 22/66 (33%) of citrate-treated patients died versus 25/72 (35%) of heparin-treated patients at 28 days, and 27/65 (42%) of citrate-treated patients died versus 29/69 (42%) of heparin-treated patients at 90 days (P = 1.00 for both). Renal outcome, i.e. independency of renal replacement therapy 28 days after initiation of CVVH in surviving patients, did not differ between groups: 29/43 (67%) in the citrate-treated patients versus 33/47 (70%) in heparin-treated patients (P = 0.82). Heparin was discontinued in 24/73 (33%) of patients whereas citrate was discontinued in 5/66 (8%) of patients (P < 0.001). Filter survival times were superior for citrate (median 46 versus 32 hours, P = 0.02), as were the number of filters used (P = 0.002) and the off time within 72 hours (P = 0.002). The costs during the first 72 hours of prescribed CVVH were lower in citrate-based CVVH., Conclusions: Renal outcome and patient mortality were similar for citrate and heparin anticoagulation during CVVH in the critically ill patient with AKI. However, citrate was superior in terms of safety, efficacy and costs., Trial Registration: Clinicaltrials.gov NCT00209378. Registered 13th September 2005.

Purpose: To evaluate the efficacy and outcome of thrombolysis and thrombectomy for thrombosed polytetrafluoroethylene stent-grafts inserted in the superficial femoral artery (SFA) for occlusive disease., Methods: A retrospective review was conducted of 79 consecutive patients with a thrombosed SFA endograft between November 2001 and December 2011. Of these, 46 (58%) were treated with thrombolysis (n=40, 87%) or thrombectomy (n=6, 13%) and form the study group (33 men; median age 66.8 years, range 30-80). Median time from stent-graft insertion to thrombosis was 3 months (range 0-53)., Results: Thrombolysis was successful in 38 (95%) patients over a mean 24 hours (range 3-48); one patient had failed lysis and another died during lytic treatment. Thrombectomy was successful in all 6 patients. Thrombosis without a causal lesion was significantly more common in occlusions that presented <30 days after insertion (p=0.01). Over a median follow-up of 14 months (range 1-69), reinterventions were performed for restenosis in 12 patients and reocclusion in 14 patients, all within 18 months after thrombolytic treatment. More than a third of patients (16/45) had definitive failures (2/6 from the thrombectomy group); 4 were treated conservatively (no/minor symptoms) and 12 had bypass grafts. Three (7%) patients eventually required a major amputation. The primary, assisted primary, and secondary patency rates of thrombolysis at 6 months were 56%, 56%, and 68%, respectively. Secondary patency for the entire cohort was 58% at 1 year., Conclusion: Thrombolysis and thrombectomy of thrombosed endografts in the SFA is effective and safe. Patency rates after treatment are moderate, but prolonged secondary patency can be achieved.

Objective: In a proportion of patients with preeclampsia, unremodeled spiral arteries develop additional pathological changes, termed decidual vasculopathy (DV), or acute atherosis. DV has been correlated to adverse clinical outcome and increased placental pathology. However, it was unclear whether these effects pertained to individual features of DV., Methods: We performed a reanalysis of placental samples from preeclamptic pregnancies (n = 76), recording the number of vessels with DV, their location in the decidua and their morphological features. Results were correlated with clinical and placental parameters, using Spearman's rho test. P-value < 0.05 was considered significant., Results: Total number of vessels with DV (totalDV) correlated with higher diastolic blood pressure, higher urine protein-to-creatinine ratio, shorter gestational age, lower birth weight, 5 min APGAR score and umbilical artery pH, and with increased accelerated villous maturity, infarction and hematoma formation, but not with HELLP syndrome markers. Additionally, there was a striking correlation of increased perinatal mortality with the number of vessels located in the decidua basalis (DVbas), and with vessels showing DV with thrombosis (DVthrom). Other morphological features, such as foam cell infiltration, did not increase correlation strength., Discussion: In our study of preeclamptic placental samples, totalDV related to worse clinical outcome and increased placental pathology. Moreover, DVbas and DVthrom related to perinatal death. DV could be a manifestation of an underlying (vascular) pathology, increasing the risk of adverse pregnancy outcome., Conclusions: In preeclampsia, totalDV, DVbas and DVthrom correlated with increased placental pathology and adverse maternal and fetal outcome, most relevantly with perinatal mortality., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Results of trials with new oral anticoagulant drugs and vitamin K antagonists (VKA) might not be directly applicable to Dutch clinical practice due to the high level of control of anticoagulation in the Netherlands. In addition, the Dutch method for assessing anticoagulation control uses cross-sectional international normalised ratio (INR) test results while the method used in the trials is based on person-time. To enable comparisons, the two calculation methods were applied to INR data of a cohort of 5422 atrial fibrillation patients treated with VKA. Overall, 74% of test results and 77% of person-time were in the therapeutic range [2.0-3.5]. For the narrower target INR interval [2.5-3.5], 59% of test results and 61% of person-time were in range. It was only between two and six months after the start of treatment that the percentage of person-time in range was lower than the percentage of test results in range. Control of anticoagulation, expressed as a percentage of person-time spent in range, in this Dutch dataset was similar to recent trials with new oral anticoagulants, although it should be noted that the Dutch INR target is higher than the target in these trials. INR control as estimated by the two calculation methods (cross-sectional and longitudinal) was similar.

Background: Partial thrombosis of the false lumen has been reported as a significant predictor of mortality during follow-up in patients with acute type B aortic dissection. The purpose of this study was to investigate the correlation of false lumen thrombosis and aortic expansion during follow-up in patients with acute type B aortic dissection., Methods: All medically treated patients with acute type B aortic dissection observed in 4 cardiovascular referral centers between 1998 and 2011, with admission and follow-up computed tomography or magnetic resonance imaging scans, were included. Aortic diameters of the dissected aortas were measured at 4 levels on the baseline and follow-up scans, and annual growth rates were calculated. Univariate and multivariate regression analyses were used to investigate the effect of false lumen thrombosis on aortic growth rate., Results: A total of 84 patients were included, of whom 40 (47.6%) had a partially thrombosed false lumen, 7 (8.3%) had a completely thrombosed false lumen, and 37 (44.0%) had a patent false lumen. A total of 273 of the 336 (81.3%) evaluated aortic levels were dissected segments. Overall, the mean aortic diameter increased significantly at all evaluated levels (P < .001). Univariate analysis showed that annual aortic growth rates were significantly higher in those segments having a false lumen with partial thrombosis (mean, 4.25 ± 10.2) when compared with the patent group (mean, 2.10 ± 5.56; P = .035). In multivariate analysis, partial lumen thrombosis was an independent predictor of higher aortic growth (adjusted mean difference, 2.05 mm/year; 95% confidence interval, 0.10-4.01; P = .040)., Conclusions: In patients with acute type B aortic dissection, aortic segments with a partially thrombosed false lumen have a significantly higher annual aortic growth rate when compared with those presenting with patent or complete thrombosis of the false lumen. Therefore, patients with partial thrombosis require more intensive follow-up and may benefit from prophylactic intervention., (Copyright © 2013 The American Association for Thoracic Surgery. All rights reserved.)

Endocrine disorders affect both the coagulation and fibrinolytic systems, and have been associated with the development of cardiovascular diseases. Thrombin-activatable fibrinolysis inhibitor (TAFI) is a link between coagulation and the fibrinolytic system. The aim of this study was to determine the effect of thyroid hormone excess and deficiency on TAFI levels and function. The effect of hyperthyroxinemia on TAFI was studied in healthy volunteers who were randomised to receive levothyroxine or no medication for 14 days in a crossover design. The effect of hypothyroidism on TAFI was studied in a multicentre observational cohort study. Blood was drawn before treatment of patients with newly diagnosed hypothyroidism and when euthyroidism was achieved. Plasma clot-lysis times, activated TAFI (TAFIa)-dependent prolongation of clot-lysis and TAFI levels were measured. Thyroid hormone excess resulted in a hypofibrinolytic condition and in an enhanced TAFIa-dependent prolongation of clot lysis. A trend towards decreased plasma TAFI levels was observed in healthy volunteers who used levothyroxine. Hypothyroidism resulted in hyperfibrinolysis and a reduced TAFIa-dependent prolongation of clot lysis. In conclusion, alterations of TAFIa-dependent prolongation of clot lysis in patients with thyroid disorders may cause an impaired haemostatic balance. The disturbed haemostatic balance in patients with hyperthyroidism might make them prone to thrombosis, while the risk for bleeding may increase in patients with hypothyroidism.

Background: Microsurgical tissue transfer is a standard procedure in reconstructive surgery of defects in head and neck oncology patients. According to the literature vascular thrombosis occurs in 8-14% of cases and is considered to be the main reason for flap failure. A review of the literature on this subject was carried out and related to the quality guidelines of the Department of Cranio-Maxillofacial Surgery in the Maastricht University Medical Centre. We defined quality indicators and quality goals for the reconstruction of head and neck defects. We investigated whether or not these parameters are practicable in a specialized head and neck cancer unit., Patients and Methods: We included 81 consecutive patients with oral cancer/osteoradionecrosis of the mandible who received a microsurgical free tissue transfer for reconstruction. The patients were treated in our institution between August 2007 and December 2011. Patient data were collected in a prospective database. Follow-up was conducted in the Department of Cranio-Maxillofacial Surgery. Data were analysed for the defined reference groups, and the results were compared with the quality goals., Results: Median follow-up was 29.1 (range 1-55) months. There were only six (7.4%) immediate complications leading to compromised flaps. Among the complications were four (5.0%) anastomosis-related complications and two haematomas (2.5%). There was no flap loss. Based on the quality goals we were able to reach an overall flap success rate of 100%., Conclusion: Most of the defined quality goals can be attained in a specialized head and neck unit. Careful patient selection, pharmacologic, non-pharmacologic and surgical measures for preventing thrombosis, such as meticulous micro-vascular surgery are considered to be essential. No consensus in the literature was found on how complications could best be prevented. The role of a standardized pre-, peri- and postoperative management is presented. The importance of thorough planning and the technical skill of the reconstructive surgeon are highlighted. The debate on quality goals has the potential to enable further improvement in the care of head and neck cancer patients., (Copyright © 2012 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.)

Background: For many years, international guidelines have advised health care professionals not to adjust oral antithrombotic medication (OAM) regimens before invasive dental procedures. The authors conducted a study to examine the opinions of Dutch general dentists regarding the dental care of patients receiving treatment with these medications., Methods: The authors invited via e-mail 1,442 general dentists in the Netherlands to answer a 20-item Internet-based questionnaire that they developed. Survey items consisted of questions about medical history taking, number of patients in the dental practice receiving OAM therapy, frequency of consulting with medical and dental colleagues and suggested dental treatment of patients during various invasive dental procedures., Results: A total of 487 questionnaires were returned (response rate of 34 percent). The mean age of respondents was 47 years, and 77 percent were male. The majority of dentists responded that they obtain medical histories, but that they did not know how many of their patients were receiving OAM treatment. Dentists reported that they consult with medical colleagues frequently about antithrombotic medication. Ninety-one percent of respondents stated that they obtained their medical knowledge primarily in dental school. More than 50 percent of the dentists reported that they were not familiar with the international normalized ratio. The majority of dentists responded that they felt a need for clinical practice guidelines., Conclusions: According to the results of our survey, most dentists remain cautious when performing invasive dental procedures in patients who are treated with OAMs. Moreover, survey respondents tended to estimate that the risk of bleeding during dental procedures when OAM therapy is continued is higher than the risk of rethrombosis when use of antithrombotic medication is interrupted., Clinical Implications: A growing proportion of elderly patients and those with medically complex conditions are being treated in dental practices in the Netherlands. Consequently, more needs to be done to ensure that dentists are offered evidence-based guidance when treating patients who receive OAMs.

Background: In the prospective randomized TRIAS pilot study, the bio-engineered Genous™ endothelial progenitor cell capturing stent was compared with the Taxus Liberté™ SR paclitaxel-eluting stent. At 1 yr, a statistically nonsignificant difference in the rates of target vessel failure (cardiac death, myocardial infarction, or target vessel revascularization) was observed. We have evaluated the safety and efficacy up to 2 yr., Methods: A total of 193 patients with de novo coronary artery lesions carrying a high risk of restenosis were randomized to a Genous stent versus a Taxus stent. Dual antiplatelet therapy was prescribed for ≥1 month after Genous stent implantation and for ≥6 months after a Taxus stent., Results: Between 1 and 2 yr, patients treated with the Genous stent tended to have fewer episodes of target lesion revascularization (2.0% versus 5.3%), but nearly similar rates of cardiac death (1.0% versus 0%), myocardial infarction (0% versus 1.1%), and stent thrombosis (0% versus 1.1%) when compared with the Taxus stent. As a result, at 2-yr follow-up treatment with the Genous stent compared with the Taxus stent resulted in a nonsignificant difference in target vessel failure (TVR) (20.4% versus 15.8%; risk difference 4.6%, 95% CI -6.2-15.5%). No stent thrombosis was observed in the Genous group compared to five cases (in four patients) in the Taxus group, resulting in a difference as compared with the Taxus stent (risk difference -4.2%; 95%CI -8.2% to -0.2%)., Conclusions: In the TRIAS pilot study, treatment of coronary artery lesions carrying a high risk of restenosis with the Genous compared with the Taxus stent resulted in a nonsignificant difference of TVR at 2-yr follow-up, with convergence of the Kaplan-Meier curves between 1 and 2 yr. Stent thrombosis was only observed after Taxus stent implantation., (Copyright © 2011 Wiley-Liss, Inc.)

Objectives: The purpose of this study was to evaluate the long-term outcomes of the PASSION (Paclitaxel-Eluting Versus Conventional Stent in Myocardial Infarction with ST-Segment Elevation) trial., Background: In primary percutaneous coronary intervention for acute ST-segment elevation myocardial infarction (STEMI), the use of drug-eluting stents (DES) is still controversial. Several randomized controlled trials of DES, compared with bare-metal stents (BMS), with short-term follow-up showed a reduction in target lesion revascularization (TLR), but no differences in rates of cardiac death or recurrent myocardial infarction. Moreover, the occurrence of (very) late stent thrombosis (ST) continues to be of major concern, and, therefore, long-term follow-up results are needed., Methods: We randomly assigned 619 patients presenting with STEMI to a paclitaxel-eluting stent (PES) or the similar BMS. The primary end point was the composite of cardiac death, recurrent myocardial infarction, or TLR. We performed clinical follow-up at 5 years., Results: At 5 years, the occurrence of the composite of cardiac death, recurrent myocardial infarction, or TLR was comparable at 18.6% versus 21.8% in PES and BMS, respectively (hazard ratio [HR]: 0.82, 95% confidence interval [CI]: 0.58 to 1.18, p = 0.28). The incidence of definite or probable ST was 12 (4.2%) in the PES group and 10 (3.4%) in the BMS group (HR: 1.19, 95% CI: 0.51 to 276, p = 0.68)., Conclusions: In the present analysis of PES compared with BMS in primary percutaneous coronary intervention for STEMI, no significant difference in major adverse cardiac events was observed. In addition, no difference in the incidence of definite or probable ST was seen, although very late ST was almost exclusively seen after the use of PES. (Paclitaxel-Eluting Versus Conventional Stent in Myocardial Infarction with ST-Segment Elevation [PASSION]; ISRCTN65027270)., (Copyright © 2011 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Aims: The aim of this study was to determine the role of potential triggers of stent thrombosis., Methods and Results: Patients (n = 437) with "definite" ST were recruited consecutively in the setting of a large multicentre observational cohort study. Patients were interviewed with validated questionnaires to identify one of the following triggers: i) timing of onset of ST, ii) performance of vigorous ( ≥ 6 MET) physical activity in the two hours preceding ST, iii) presence of emotional stress (experiencing a serious life event in the 14 days preceding the ST or feelings of anger in the 12 hours of ST) and iv) presence of a documented active infection at the time of ST. A total of 363 patients (83.1%) were able to supply adequate information. A significant trigger was identified in 83 patients (22.9%). Analysis of the different categories according to timing of ST revealed a higher prevalence of triggers with an increasing time-interval between index PCI and ST. Analysis of circadian variation showed a steep peak incidence from 7 am-12 pm., Conclusions: Triggering mechanisms such as time of the day, physical exertion, emotional stress and infection may play an important role in a considerable number of patients presenting with ST, in particular in patients with (very) late ST.

Objectives: The aim of this study was to assess the 6-year clinical outcome after unrestricted use of sirolimus-eluting stents (SES) or paclitaxel-eluting stents (PES) as compared with bare-metal stents (BMS) in consecutive de novo patients undergoing percutaneous coronary intervention (PCI)., Background: SES and PES have been shown to significantly decrease target vessel revascularization (TVR) rates compared with BMS in "real-world" registries. However, possible higher rates of very-late stent thrombosis and a restenosis "catch-up" trend might jeopardize the benefit., Methods: Three PCI cohorts, each with exclusive use of 1 stent type (BMS = 450; SES = 508; PES = 576), were systematically followed for the occurrence of major adverse cardiac events (MACE)., Results: Very-late stent thrombosis was more common in SES and PES patients than BMS patients (2.4% vs. 0.9% vs. 0.4%, respectively; p = 0.02); however, there were no significant differences between the stent types for all-cause mortality and all-cause mortality/myocardial infarction at 6-year follow-up. Sixty-nine SES patients (Kaplan-Meier estimate 14%) and 72 PES patients (14%) had a TVR, as compared with 79 BMS patients (18%; log-rank p = 0.02), which maintained significance after adjustment for (potential) confounders. Multivariate analysis showed that DES implantation is associated with lower incidence of TVR and MACE than BMS implantation (hazard ratio: 0.65, 95% confidence interval: 0.49 to 0.86; p = 0.003; hazard ratio: 0.79, 95% confidence interval: 0.65 to 0.97; p = 0.02, respectively). Incidence of MACE was also lower in SES and PES patients (30% and 30%, respectively) than in BMS patients (34%); however, significance was borderline., Conclusions: The unrestricted use of both DES resulted in a sustained advantage in decreasing TVR and, to a lesser extent, MACE compared with BMS at 6 years. The SES and PES are equally safe and effective in the treatment of coronary lesions., (Copyright © 2010 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Background: There are limited data on the long-term safety and efficacy profile of coronary stent implantation in patients with stable coronary artery disease (CAD) undergoing percutaneous coronary intervention (PCI)., Objective: We aimed to assess the 4-year clinical outcome in patients who received a bare-metal stent (BMS), sirolimus-eluting stent (SES), or a paclitaxel-eluting stent (PES) for the percutaneous treatment of stable angina in our center during 2000-2005., Methods: In the study period, a total of 2,449 consecutive patients (BMS = 1,005; SES = 373; and PES = 1071) underwent a PCI as part of three historical PCI-cohorts for stable angina and were routinely followed for the occurrence of major adverse cardiac events (MACE)., Results: At 4 years follow-up, 264 BMS patients (26.8%) had a MACE, compared to 75 SES patients (20.9%) and 199 PES patients (23.9%). Multivariate analysis showed that SES and PES were superior to BMS with respect to MACE [hazard ratio (HR) = 0.62, 95% confidence interval (CI): 0.47-0.81; HR = 0.67, 95% CI: 0.55-0.82, respectively]. The occurrence of MACE was significantly lower in the SES and PES population, primarily due to less target-vessel revascularization (TVR) procedures (HR = 0.53, 95% CI: 0.37-0.75; HR = 0.71, 95% CI: 0.62-0.81, respectively). The occurrence of early, late, and very late stent thrombosis was equally rare with each stent type. There were no significant differences between SES and PES on death, myocardial infarction, TVR, and MACE., Conclusion: These findings suggest that SES and PES result in decreased TVR procedures and MACE compared to BMS at 4 years follow-up. SES or PES implantation should be the preferred choice over BMS for patients with stable CAD undergoing PCI., ((c) 2010 Wiley-Liss, Inc.)

Purpose: Central venous catheters (CVCs) are frequently used in patients with a haematological malignancy in order to administer chemotherapy, stem cell infusions, blood products, medication, parenteral hyperalimentation as well as for blood sampling. Reported complications consist of mechanical complications during the insertion and long-term complications such as CVC-related thrombosis and infections. CVC-related thrombosis and infections are frequently occurring complications and may cause significant morbidity in patients with haematological malignancies. CVC-related infections and thrombosis should not be considered as a result of modern care or fait accompli and must be one of the priority targets of a multidisciplinary approach emphasizing quality-of-care improvement., Methods: We conducted a survey among 23 Dutch and Belgian haematological centres to assess the local views and clinical practices concerning central venous catheters in haematological patients., Results and Conclusions: The local protocols and policies differ greatly among the centres probably reflecting wide differentiations in practice across Europe. It also shows lack of evidence concerning CVC-related thrombosis and infections which may cause morbidity in haematological patients. Further research has to be stimulated and development of clinical practice guidelines should be promoted.

Aims: Evidence regarding the optimal treatment of non-culprit lesions detected during primary PCI is lacking. Our aim was to investigate whether early invasive treatment improves left ventricular ejection fraction (EF) and prevents major adverse cardiac events (MACE)., Methods and Results: Of 121 patients with at least one non-culprit lesion, 80 were randomised to early FFRguided PCI (invasive group), and 41 to medical treatment (conservative group). Primary endpoint was EF at six months, secondary endpoints included MACE. In the invasive group, early angiography was performed 7.5 days (5-20) after primary PCI. Forty percent of the non-culprit lesions did not show haemodynamic significance (FFR > 0.75). Subsequent PCI of at least one non-culprit lesion was performed in 52%, PCI without preceding FFR was performed in 8% and elective CABG was done in 4%. No in-hospital events occurred in the conservative group. After six months, EF was comparable (59+/-9% vs. 57+/-9%, p=0.362), and there was no difference in MACE between invasively and conservatively treated patients (21 vs. 22%, p=0.929)., Conclusions: An invasive strategy towards non-culprit lesions does not lead to an increase in EF or a reduction in MACE. The functional stenosis severity of non-culprit lesions is frequently overestimated.

Background: Oral anticoagulant therapy is effective for the prevention of arterial thromboembolism in various patient groups. The increased risk of hemorrhage remains the major drawback to this therapy and is associated with the intensity of anticoagulation. Finding the optimal intensity at which the overall incidence rate of both bleeding and thromboembolic events is minimized represents a way to improve the safety of oral anticoagulant treatment., Methods: We evaluated all patients visiting the Leiden Anticoagulation Clinic with mechanical heart valve prostheses, atrial fibrillation, or myocardial infarction from 1994 to 1998. Untoward events were major thromboembolism and major hemorrhage. We calculated intensity-specific incidence rates of untoward events to assess the optimal intensity per indication of treatment. We enrolled 4202 patients for a total of 7788 patient-years., Results: A total of 3226 hospital admissions were reported, 306 owing to an untoward event. Incidence rates of untoward events were around 4% per year for all indications: 4.3 (95% confidence interval [CI], 3.1-5.6) for patients with mechanical heart valve prostheses, 4.3 (95% CI, 3.7-5.1) for patients with atrial fibrillation, and 3.6 per year (95% CI, 3.0-4.4) for patients treated after a myocardial infarction. The optimal intensity of anticoagulation for patients with mechanical heart valve prostheses was an international normalized ratio (INR) of 2.5 to 2.9; for patients with atrial fibrillation, an INR of 3.0 to 3.4; and for patients after myocardial infarction, an INR of 3.5 to 3.9., Conclusion: Our study suggests target INRs of 3.0 for patients with mechanical heart valve prostheses and atrial fibrillation and 3.5 after myocardial infarction as a starting point in future clinical trials.

Objectives: We investigated the impact of sex on outcomes after percutaneous coronary intervention (PCI) with drug-eluting stent (DES)., Background: Women have a higher risk of adverse outcomes after PCI than do men. However, long-term outcomes of women after contemporary PCI with DES have not been fully investigated., Methods: We performed a retrospective cohort study of 4,936 consecutive patients (28.2% women) who underwent PCIs between 2000 and 2004, before and after introduction of DES (bare-metal stent [BMS] group: n = 2,131, DES group: n = 2,805), to assess the impact of sex on long-term PCI outcomes and to compare outcome after PCI of women between the DES and BMS eras., Results: Compared with men, women undergoing PCIs were 5 years older and more frequently have comorbidities such as diabetes mellitus and hypertension. In patients treated throughout the BMS and DES eras, there were no differences by sex for risk of all-cause death, myocardial infarction, or target vessel revascularization 3 years after procedure. The procedural complexity was higher in the DES era, nevertheless, risk for target vessel revascularization and major adverse cardiac event at 3 years were significantly lower in women treated with DES than in women treated with BMS (adjusted hazard ratio [HR] for target vessel revascularization: 0.52 [95% confidence interval (CI): 0.36 to 0.75], adjusted HR for major adverse cardiac event: 0.63 [95% CI: 0.48 to 0.83])., Conclusions: Although women had worse baseline characteristics, no differences in 3-year outcomes were observed between men and women. Compared with BMS use, DES use has decreased revascularization rate equally in women and men.

Background and Objectives: Vascular access standards are predominantly based on older, single-center reports; however, the hemodialysis population has changed dramatically and primary arteriovenous fistula failure is a huge problem. This prospective, multicenter study used standardized definitions to analyze patency rates and potential risk factors that affect functional patency and late arteriovenous fistula functionality., Design, Setting, Participants, & Measurements: Eleven centers participated in a guidelines implementation program. All new permanent vascular accesses were included. Patency and functional patency, defined as access survival from creation and from first dialysis use, respectively, were calculated using Kaplan-Meier analysis. Risk factors for primary functional patency loss (intervention-free interval) and secondary failure (abandonment) were determined using regression models., Results: A total of 491 arteriovenous fistulas were placed in 395 patients. Six-, 12-, and 18-mo secondary patency and functional patency were 75 +/- 2.0, 70 +/- 2.3, and 67 +/- 2.7% and 90 +/- 1.9, 88 +/- 2.2, and 86 +/- 2.7%, respectively. Primary failure rate was 40%. Thrombosis rate was 0.14 per patient-year. Diabetes and arteriovenous fistula surveillance were significantly associated with primary functional patency loss. Preoperative duplex was inversely related to secondary failure. The secondary failure rate per hospital varied from 0 to 39%., Conclusions: This study showed a marked difference between patency and functional patency, likely to be explained by high primary failure rates. Hemodialysis patients with diabetes can be expected to have reduced primary functional patency rates, but if treated adequately, then arteriovenous fistula functionality can be maintained as long as in patients without diabetes.

Background: A prothrombotic or hypercoagulable state in atrial fibrillation may contribute to stroke and thromboembolism. Results of longitudinal population-based studies in elderly people with atrial fibrillation are not yet available., Methods: In the Rotterdam Study, a population-based prospective cohort study, 162 participants with atrial fibrillation at baseline, aged 55 years and over, were matched for age and gender with 324 people in sinus rhythm. Associations were examined between three coagulation factors and the risk of total and cardiac mortality and stroke. Hazard rate ratios were calculated with 95% confidence intervals using Cox's proportional hazards model, adjusted for potential confounders., Results: Plasma von Willebrand factor was, age- and gender-adjusted, associated with cardiac mortality in the total population (relative risk 1.16; 1.06-1.27, per 10 IU dL(-1) increase), but statistical significance was lost after additional adjustments. A strong association (1.27; 1.08-1.50, per 5-unit increase) was found between soluble P-selectin (sP-sel) and cardiac mortality in atrial fibrillation patients but not in participants in sinus rhythm. Furthermore, the expected association between fibrinogen and cardiac mortality was observed only in those in sinus rhythm (2.60; 1.69-4.01, per unit increase), and not in atrial fibrillation. No associations were found between coagulation factors and stroke., Conclusions: In this population-based study, plasma levels of sP-sel predicted clinical adverse outcomes in atrial fibrillation, suggesting a role of platelets in the prothrombotic state associated with atrial fibrillation. Fibrinogen was a risk factor of cardiac and all-cause mortality in sinus rhythm, but not in atrial fibrillation.

Objective: To determine which thromboprophylactic modalities were used by general surgeons in the Netherlands; to check current clinical practice against national and international guidelines., Design: Descriptive., Method: In April 2004 a questionnaire was sent to all 106 surgical practices in the Netherlands with questions regarding the use of thromboprophylaxis before, during and after various surgical interventions. Practice was compared with guidelines from the Dutch Institute for Healthcare Improvement CBO, the Dutch Surgical Association and the American College of Chest Physicians., Results: We obtained data from 92 (87%) surgical practices. Low molecular weight heparin was initiated before surgery by 92% of respondents. Risk factors such as age (72%) and prior venous thromboembolism (76%) played an important role in determining the thromboprophylactic protocol used. During hospitalisation, variations were seen primarily for operations performed on an out-patient basis: 61% of surgeons gave thromboprophylaxis in this setting. Prolonged thromboprophylaxis after hospital discharge was seldom administered. 54% of surgeons used prolonged thromboprophylaxis after surgery for hip or femur fractures. During cast immobilisation of the upper leg, 79% of all surgeons prescribed thromboprophylaxis., Conclusion: Current practice regarding thromboprophylaxis during hospitalisation conformed consistently to the guidelines. The guidelines were followed moderately with regard to the use of prolonged thromboprophylaxis following hip fractures. In the absence of clear guidelines, there were striking differences among surgical practices regarding thromboprophylaxis during out-patient care and plaster cast immobilisation.

Background and Objectives: The purpose of this study was to assess the incidence of central venous catheter (CVC)-related thrombosis and the contribution of two common inherited coagulation disorders (factor V Leiden, prothrombin G20210A mutation) to this complication in a large hospital population., Design and Methods: In a prospective setting, patients were assessed daily for signs and symptoms suggestive of thrombosis. Routine Doppler-ultrasound was performed weekly in all patients until CVC removal. Doppler-ultrasound examinations were stored on videotape and assessed by two blinded observers. In the case of clinically suspected thrombosis the physicians followed routine diagnostic and therapeutic procedures. The presence of factor V Leiden and prothrombin G20210A mutation and other potential risk factors were assessed in all patients., Results: In 252 consecutive patients the cumulative incidence of-CVC related thrombosis was 30% (clinically manifested thrombosis: 7%). The relative risk of factor V Leiden or prothrombin G20210A mutation for thrombosis was 2.7 (CI95% 1.9 to 3.8). In addition, a personal history of venous thrombosis was associated with CVC-related thrombosis, whereas the severity of thrombosis was affected by the absence of anticoagulants and the presence of cancer., Interpretation and Conclusions: Thrombosis is frequently observed after central venous catheterization. Common inherited abnormalities in blood coagulation contribute substantially to CVC-related thrombosis. In view of physicians' reluctance to prescribe prophylactic anticoagulant treatment in vulnerable patients, a priori determination of common inherited and acquired risk factors may form a basis to guide these treatment decisions.

Background: Tunnelled venous catheters improve venous access in cancer patients, but are associated with complications. We retrospectively analysed the outcome of Hickman catheter and Port-A-Cath (PAC) insertion in cancer patients from a department of medical oncology and compared these results with the literature., Methods: The files of patients in whom insertion of a Hickman or PAC was planned in the period March 1992 to August 1999 were analysed., Results: In total, 150 files were evaluated. In 149 patients, 128 Hickman catheters and 38 PACs were inserted successfully. Complications occurred in 44.6% of the catheters inserted successfully. Infection (24.1%) and thrombosis (7.2%) were observed most frequently. In 66.7% of patients with thrombosis, the catheter tip was positioned incorrectly. Removal for catheter-related complications occurred in 47.7%. Of 146 catheter insertions for which the name of the responsible (resident) surgeon could be traced, 48 different names were identified., Conclusions: In comparison with other studies, we found a high incidence of infections and a high removal rate for catheter-related complications. We confirmed the relationship between thrombosis and an inadequate position of the catheter tip. The level of experience of the (resident) surgeon performing the catheter insertion may have played a role in the high complication rate.

Objective: the aim of this study was to determine the pattern of shrinkage after endovascular aneurysm repair (EAR) using logarithmic, exponential and linear models and to calculate a lag time is present., Patients and Methods: patients with a complete CTA follow-up of 2 years and a primary shrinking aneurysm were included, resulting in a study group of 29 patients. Six functions, logarithmic, exponential and linear, all with and without lag time, were fitted to the thrombus volume obtained from measurements postoperative and after 6, 12 and 24 months. The correlation coefficient was used to determine the association between the calculated and measured values. A correlation coefficient >0.95 was considered a good fit., Results: a logarithmic model produced the best fits. From the 29 patients, two patients could not be described by any model. The remaining 27 patients could be fitted using a logarithmic function with a correlation coefficient of >0.95 (median 0.99, range 0.95-1.00). Twenty-two of these patients had a lag time (median 63.4 days, range 5.8-252.3). Only five of the initial 44 patients (11%) showed immediate sac shrinkage., Conclusion: almost all shrinkage processes could be described by a logarithmic function. In over 75% of patients a lag time to shrinkage could be calculated. In only a small proportion did the shrinking process start immediately after EAR., (Copyright 2002 Harcourt Publishers Limited.)

Background and Purpose: Epidemiological studies have shown an increased risk of venous thrombosis in women taking third-generation oral contraceptives, ie, those containing the progestogens desogestrel or gestodene. This study assesses the risk of ischemic stroke with several types of oral contraceptives., Methods: A multicenter, population-based, case-control study was performed in 9 Dutch centers in women aged 18 to 49 years. Women with a first ischemic stroke were compared with control women without vascular diseases. The control subjects were recruited by random-digit dialing and were stratified by age, area of residence, and year of stroke. All patients and control subjects filled in a questionnaire about the use of oral contraceptives and risk factors for ischemic stroke. Odds ratios were adjusted for the stratification factors., Results: Two hundred three women with an ischemic stroke and 925 control women were included. The risk of stroke in women using any type of oral contraceptives versus none was 2.3 (95% CI 1.6 to 3.3). Current users of first-generation oral contraceptives had an odds ratio of 1.7 (95% CI 0.7 to 4.4). Low-dose second-generation oral contraceptives increased the risk of stroke 2.4 times (95% CI 1.6 to 3.7), and third-generation oral contraceptives increased the risk of stroke 2.0 times (95% CI 1.2 to 3.5). The risk of stroke in women using third-generation oral contraceptives was not different from that in women using second-generation oral contraceptives (odds ratio 1.0, 95% CI 0.6 to 1.8)., Conclusions: Third-generation oral contraceptives (containing desogestrel or gestodene) confer the same risk of first ischemic stroke as second-generation oral contraceptives (containing levonorgestrel).

The association between plasma fibrinogen, factor VII, factor X, activated partial thromboplastin time, antithrombin III and the lifestyle factors cigarette smoking, alcohol use, fat intake and physical activity was assessed in 802 men aged 70-90 years in Zutphen (The Netherlands), Montegiorgio and Crevalcore (Italy). Smoking was positively associated with fibrinogen, also after adjustment for other lifestyle factors, age, use of anticoagulants and aspirin like drugs, body mass index, and history of myocardial infarction. Alcohol use was associated with increased levels of factor X and decreased levels of antithrombin III. Fat intake was positively associated with antithrombin III. Between cohorts, considerable differences were observed in levels of haemostatic parameters and the lifestyle factors. Compared to the mediterranean cohorts the Zutphen cohort showed the highest levels of fibrinogen and factor VII. Differences in lifestyle factors could, however, not explain differences between cohorts in levels of any of the haemostatic parameters, despite the observed associations between lifestyle factors and haemostatic parameters.

Objective: The outcome of renal transplantation with an arterial anastomosis to a vascular prosthesis in the aortofemoral tract is evaluated., Patients and Methods: All 7 Dutch transplant centers were invited to review their experience. Among a total of 5791 cadaveric renal transplantations performed between 1978 and 1994, 13 cases (0.2%) in 3 different centres were identified. In 6 cases the vascular reconstruction and transplant operation were performed simultaneously, and in 7 cases separately, with a mean interval of 3.5 yr. The indications for vascular reconstruction were aneurysmal disease in 4 and obstructive disease in 9 cases., Results: The early vascular complications of these procedures were hemorrhage in 4 and renal vein thrombosis in 1 and led to graft loss in 3 cases. The perioperative mortality was 2/13 (15%). The graft and patient survival were 68 and 83% respectively after 1 yr and 17 and 37% after 5 yr. Late mortality was mainly due to cardiovascular disease., Conclusions: Renal transplantation with an arterial anastomosis to a vascular prosthesis in the aortofemoral tract is a hazardous procedure with relatively poor short- and long-term results. These observations should be considered in the choice of renal replacement therapy in this special patient population.