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Dive into the research topics where Yolanda van der Graaf is active.

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Featured researches published by Yolanda van der Graaf.


The Lancet | 2010

Vertebroplasty versus conservative treatment in acute osteoporotic vertebral compression fractures (Vertos II): an open-label randomised trial

Caroline A H Klazen; Paul N.M. Lohle; Jolanda De Vries; Frits H. Jansen; Alexander V. Tielbeek; Marion C Blonk; A. Venmans; Willem Jan van Rooij; Marinus C Schoemaker; Job R Juttmann; Tjoen H Lo; Harald J. J. Verhaar; Yolanda van der Graaf; Kaspar J. van Everdingen; Alex F Muller; Otto Elgersma; Dirk R Halkema; H. Fransen; Xavier Janssens; Erik Buskens; Willem P. Th. M. Mali

BACKGROUND Percutaneous vertebroplasty is increasingly used for treatment of pain in patients with osteoporotic vertebral compression fractures, but the efficacy, cost-effectiveness, and safety of the procedure remain uncertain. We aimed to clarify whether vertebroplasty has additional value compared with optimum pain treatment in patients with acute vertebral fractures. METHODS Patients were recruited to this open-label prospective randomised trial from the radiology departments of six hospitals in the Netherlands and Belgium. Patients were aged 50 years or older, had vertebral compression fractures on spine radiograph (minimum 15% height loss; level of fracture at Th5 or lower; bone oedema on MRI), with back pain for 6 weeks or less, and a visual analogue scale (VAS) score of 5 or more. Patients were randomly allocated to percutaneous vertebroplasty or conservative treatment by computer-generated randomisation codes with a block size of six. Masking was not possible for participants, physicians, and outcome assessors. The primary outcome was pain relief at 1 month and 1 year as measured by VAS score. Analysis was by intention to treat. This study is registered at ClinicalTrials.gov, number NCT00232466. FINDINGS Between Oct 1, 2005, and June 30, 2008, we identified 431 patients who were eligible for randomisation. 229 (53%) patients had spontaneous pain relief during assessment, and 202 patients with persistent pain were randomly allocated to treatment (101 vertebroplasty, 101 conservative treatment). Vertebroplasty resulted in greater pain relief than did conservative treatment; difference in mean VAS score between baseline and 1 month was -5·2 (95% CI -5·88 to -4·72) after vertebroplasty and -2·7 (-3·22 to -1·98) after conservative treatment, and between baseline and 1 year was -5·7 (-6·22 to -4·98) after vertebroplasty and -3·7 (-4·35 to -3·05) after conservative treatment. The difference between groups in reduction of mean VAS score from baseline was 2·6 (95% CI 1·74-3·37, p<0·0001) at 1 month and 2·0 (1·13-2·80, p<0·0001) at 1 year. No serious complications or adverse events were reported. INTERPRETATION In a subgroup of patients with acute osteoporotic vertebral compression fractures and persistent pain, percutaneous vertebroplasty is effective and safe. Pain relief after vertebroplasty is immediate, is sustained for at least a year, and is significantly greater than that achieved with conservative treatment, at an acceptable cost. FUNDING ZonMw; COOK Medical.


Stroke | 1999

Treatment of Intracranial Aneurysms by Embolization with Coils A Systematic Review

Eva H. Brilstra; Gabriel J.E. Rinkel; Yolanda van der Graaf; Willem Jan van Rooij; Ale Algra

BACKGROUND Embolization with coils is increasingly used for the treatment of intracranial aneurysms. To assess the percentage of complications, the percentage of aneurysm occlusion, and the short-term outcome, we performed a systematic review of studies on embolization with controlled detachable or pushable coils. SUMMARY OF REVIEW To find studies on embolization with coils, we performed a MEDLINE search from January 1990 to March 1997, checked all reference lists of the studies found, performed a Science Citation Index search on Guglielmi, and hand searched recent volumes of 25 journals. Two authors independently extracted data by means of a standardized data extraction form from 48 eligible studies totalling 1383 patients. Permanent complications of embolization with controlled detachable coils occurred in 46 of 1256 patients (3.7%; 95% CI, 2.7% to 4.9%); 400 of 744 aneurysms (54%; 95% CI, 50% to 57%) were completely occluded. By means of weighted linear regression, no relation between baseline characteristics and outcome measurements was found. The results in the prespecified subgroups of patients with a ruptured aneurysm, an unruptured aneurysm, or a basilar bifurcation aneurysm were essentially the same as the overall results. CONCLUSIONS Short-term results indicate that embolization with coils is a reasonably safe treatment for patients with an unruptured aneurysm and for patients with aneurysmal subarachnoid hemorrhage. The effectiveness in terms of complete occlusion of the aneurysm is moderate. Randomized trials are warranted to compare surgical clipping with embolization with coils.


Circulation | 1999

Common Carotid Intima-Media Thickness and Arterial Stiffness Indicators of Cardiovascular Risk in High-Risk Patients The SMART Study (Second Manifestations of ARTerial disease)

P.C.G. Simons; Ale Algra; Michiel L. Bots; Diederick E. Grobbee; Yolanda van der Graaf

BACKGROUND Common carotid intima-media thickness (IMT) and distensibility are markers of structural and functional vessel wall properties. Both parameters have been found in population-based studies to be associated with cardiovascular risk factors and prevalent cardiovascular disease. We investigated cross-sectionally whether IMT and distensibility are associated with cardiovascular risk in patients who already have vascular disease or atherosclerotic risk factors and evaluated the diagnostic ability of IMT and distensibility to discriminate between low- and high-risk patients. METHODS AND RESULTS IMT and distensibility (change of diameter) of the left and right common carotid arteries were measured in the first 570 patients (537 for distensibility) enrolled in the Second Manifestations of ARTerial disease (SMART) study, a cohort study among patients with a manifestation of vascular disease or cardiovascular risk factors. Three risk scores were used to classify each patients vascular risk. Areas under the curve (AUCs) of receiver-operating characteristic curves were calculated for IMT and distensibility after the patients were dichotomized on the median of the risk scores as the outcome. Risk scores increased nearly linearly with increasing IMT and decreasing distensibility. The AUCs for IMT predicting high-risk patients were 0.77, 0.73, and 0.77 based on the 3 risk scores. The AUCs for distensibility were 0. 65, 0.62, and 0.66. CONCLUSIONS Common carotid IMT and distensibility are clear markers of cardiovascular risk in patients who already have vascular disease or atherosclerotic risk factors. IMT appears to discriminate between low- and high-risk patients better than distensibility.


The Lancet | 1998

Randomised comparison of primary stent placement versus primary angioplasty followed by selective stent placement in patients with iliac-artery occlusive disease

Eric Tetteroo; Yolanda van der Graaf; Johanna L. Bosch; Andries D. van Engelen; M. G. Myriam Hunink; B.C. Eikelboom; Willem P. Th. M. Mali

BACKGROUND Percutaneous transluminal angioplasty (PTA) is a safe, simple, and successful treatment for intermittent claudication caused by iliac-artery occlusive disease. Primary stent placement has been proposed as more effective than PTA. We compared the technical results and clinical outcomes of two treatment strategies-primary placement of a stent across the stenotic segment of the iliac artery, or primary PTA followed by selective stent placement when haemodynamic results were inadequate. METHODS We randomly assigned 279 patients with intermittent claudication, recruited from departments of vascular surgery, either to direct stent placement (group I, n=143) or primary angioplasty (group II, n=136), with subsequent stent placement in case of a residual mean pressure gradient greater than 10 mm Hg across the treated site. The main inclusion criterion was intermittent claudication on the basis of iliac-artery stenosis of more than 50%, proven by angiography. All patients had a clinical assessment before intervention and at 3, 12, and 24 months. Clinical success was defined as improvement of at least one clinical category. Secondary endpoints were initial technical results, procedural complications, cumulative patency as assessed by duplex ultrasonography, and quality of life. FINDINGS In group II, selective stent placement was done in 59 (43%) of the 136 patients. The mean follow-up was 9.3 months (range 3-24). Initial haemodynamic success and complication rates were 119 (81%) of 149 limbs and 6 (4%) of 143 limbs (group I) versus 103 (82%) of 126 limbs and 10 (7%) of 136 limbs (group II), respectively. Clinical success rates at 2 years were 29 (78%) of 37 patients and 26 (77%) of 34 patients in groups I and II, respectively (p=0.6); however, 43% and 35% of the patients, respectively, still had symptoms. Quality of life improved significantly after intervention (p<0.05) but we found no difference between the groups during follow-up. 2-year cumulative patency rates were similar at 71% versus 70% (p=0.2), respectively, as were reintervention rates at 7% versus 4%, respectively (95% CI -2% to 9%). INTERPRETATION There were no substantial differences in technical results and clinical outcomes of the two treatment strategies both at short-term and long-term follow-up. Since angioplasty followed by selective stent placement is less expensive than direct placement of a stent, the former seems to be the treatment of choice for lifestyle-limiting intermittent claudication caused by iliac artery occlusive disease.


American Journal of Cardiology | 2008

Relation of epicardial and pericoronary fat to coronary atherosclerosis and coronary artery calcium in patients undergoing coronary angiography.

Petra M. Gorter; Alexander M. de Vos; Yolanda van der Graaf; Pieter R. Stella; Pieter A. Doevendans; Matthijs F.L. Meijs; Mathias Prokop; Frank L.J. Visseren

Fat surrounding coronary arteries might aggravate coronary artery disease (CAD). We investigated the relation between epicardial adipose tissue (EAT) and pericoronary fat and coronary atherosclerosis and coronary artery calcium (CAC) in patients with suspected CAD and whether this relation is modified by total body weight. This was a cross-sectional study of 128 patients with angina pectoris (61 +/- 6 years of age) undergoing coronary angiography. EAT volume and pericoronary fat thickness were measured with cardiac computed tomography. Severity of coronary atherosclerosis was assessed by the number of stenotic (> or =50%) coronary vessels; extent of CAC was determined by the Agatston score. Patients were stratified for median total body weight (body mass index [BMI] 27 kg/m(2)). Overall, EAT and pericoronary fat were not associated with severity of coronary atherosclerosis and extent of CAC. In patients with low BMI, those with multivessel disease had increased EAT volume (100 vs 67 cm(3), p = 0.04) and pericoronary fat thickness (9.8 vs 8.4 mm, p = 0.06) compared with those without CAD. Also, patients with severe CAC had increased EAT volume (108.0 vs 69 cm(3), p = 0.02) and pericoronary fat thickness (10.0 vs 8.2 mm, p value = 0.01) compared with those with minimal/absent CAC. In conclusion, EAT and pericoronary fat were not associated with severity of coronary atherosclerosis and CAC in patients with suspected CAD. However, in those with low BMI, increased EAT and pericoronary fat were related to more severe coronary atherosclerosis and CAC. Fat surrounding coronary arteries may be involved in the process of coronary atherosclerosis, although this is different for patients with low and high BMIs.


Stroke | 2002

Preoperative Diagnosis of Carotid Artery Stenosis Accuracy of Noninvasive Testing

Paul J. Nederkoorn; Willem P. Th. M. Mali; B.C. Eikelboom; Otto E. H. Elgersma; Erik Buskens; M. G. Myriam Hunink; L. Jaap Kappelle; Pieter C. Buijs; Aloys F. J. Wüst; Aad van der Lugt; Yolanda van der Graaf

Background and Purpose— Carotid endarterectomy has been shown to be beneficial in symptomatic patients with a severe stenosis (70% to 99%) of the internal carotid artery (ICA). Digital subtraction angiography (DSA) is the standard of reference in the diagnosis of carotid artery stenosis but has a relatively high complication rate. In a diagnostic study we investigated the accuracy of noninvasive testing compared with DSA. Methods— In a prospective diagnostic study we performed duplex ultrasound (DUS), magnetic resonance angiography (MRA), and DSA on 350 consecutive symptomatic patients. Stenoses were measured with the observers blinded for clinical information and other test results. Separate and combined test results of DUS and MRA were compared with the reference standard DSA. Only the stenosis measurements of the arteries on the symptomatic side were included in the analyses. Results— DUS analyzed with previously defined criteria resulted in a sensitivity of 87.5% (95% CI, 82.1% to 92.9%) and a specificity of 75.7% (95% CI, 69.3% to 82.2%) in identifying severe ICA stenosis (70% to 99%). Stenosis measurements on MRA yielded a sensitivity of 92.2% (95% CI, 86.2% to 96.2%) and a specificity of 75.7% (95% CI, 68.6% to 82.5%). When we combined MRA and DUS results, agreement between these 2 modalities (84% of patients) gave a sensitivity of 96.3% (95% CI, 90.8% to 99.0%) and a specificity of 80.2% (95% CI, 73.1% to 87.3%) for identifying severe stenosis. Conclusions— MRA showed a slightly better accuracy than DUS in the diagnosis of carotid artery stenosis. To achieve the best accuracy, however, both tests should be performed subsequently.


Stroke | 2007

Asymptomatic carotid artery stenosis and the risk of new vascular events in patients with manifest arterial disease: the SMART study.

Bertine M.B. Goessens; Frank L.J. Visseren; L. Jaap Kappelle; Ale Algra; Yolanda van der Graaf

Background and Purpose— The frequency of asymptomatic carotid artery stenosis (CAS) increases with age from 0.5% in individuals below 50 years of age to 5% to 10% in individuals over 65 years of age in the general population. Its prognostic value has been examined in the general population but less often in patients with clinical manifestations of arterial disease other than retinal or cerebral ischemia. We examined the relationship between asymptomatic CAS and the risk of subsequent events in this specific group of patients. Methods— This study involved 2684 consecutive patients with clinical manifestations of arterial disease or type 2 diabetes mellitus, but without a history of cerebral ischemia, enrolled in the SMART study (Second Manifestations of ARTerial disease). The degree of asymptomatic CAS was assessed with Duplex scanning and defined on the basis of the blood flow velocity patterns at baseline in both carotid arteries. None of the patients underwent carotid endarterectomy or endovascular intervention. During the follow-up period, vascular events (vascular death, ischemic stroke, and myocardial infarction) were documented in detail. Data were analyzed with Cox proportional hazards regression and adjusted for age, gender, and classic vascular risk factors. Results— Asymptomatic CAS of 50% or greater was present in 221 (8%) patients. During a mean follow up of 3.6 years (SD=2.3), a first vascular event occurred in 253 patients (9%). The cumulative incidence rate for the composite of subsequent vascular events after 5 years was 12.3% (95% CI=10.7 to 13.9), for cerebral infarction 2.2% (95% CI=1.4 to 2.8), and for myocardial infarction 8.0% (95% CI=6.6 to 9.4). Adjusted for age and gender, asymptomatic CAS of 50% or greater was related to a higher risk of subsequent vascular events (hazard ratio=1.5, 95% CI=1.1 to 2.1), in particular of vascular death (hazard ratio=1.8, 95% CI=1.2 to 2.6). After additional adjustment for vascular risk factors, the hazard ratios remained essentially the same. Conclusion— Asymptomatic carotid artery stenosis is an independent predictor of vascular events, especially vascular death, in patients with clinical manifestations of arterial disease or type 2 diabetes but without a history of cerebral ischemia.


Circulation | 2003

Coronary Collaterals An Important and Underexposed Aspect of Coronary Artery Disease

Jeroen Koerselman; Yolanda van der Graaf; Peter de Jaegere; Diederick E. Grobbee

Important risk factors for cardiovascular disease (CVD) have been identified, but they fail to explain why some patients with atherosclerosis become symptomatic and have recurrent symptomatic disease, and others do not. Apart from the extent of coronary atherosclerosis (among other factors), the sensitivity of organs to episodes of ischemia is probably of importance. An organ may be less sensitive to episodes of ischemia if supplied with sufficient blood flow by well-developed collateral vessels. Unfortunately, some organs or even some individuals do not appear to have well-developed collateral vessels, if developed at all. At present, it is not clear why there are differences between individuals in their capability of developing a sufficient collateral circulation. The potential of individuals to develop coronary collateral circulation has so far been largely neglected but may play a major role in determining myocardial vulnerability. In the present article, we propose why coronary collaterals are important, and why this individual potential to develop collaterals should be considered an additional indicator of cardiac vulnerability. Also, we review determinants that play a role in collateral coronary blood supply. Coronary collaterals, or “natural bypasses,” are anastomotic connections without an intervening capillary bed between portions of the same coronary artery and between different coronary arteries (Figure 1).1 Collateral circulation potentially offers an important alternative source of blood supply when the original vessel fails to provide sufficient blood.2 Timely enlargement of collaterals may even avoid transmural myocardial infarction (MI) and death in symptomatic patients.3 As early as in 1956, Baroldi et al4 demonstrated the presence at birth of mostly corkscrew-shaped collaterals in normal human hearts, with a lumen diameter of 20 to 350 μm and lengths ranging from 1 or 2 cm to 4 or 5 cm. In hearts with typical findings of coronary disease at autopsy, …


Journal of Vascular Surgery | 2008

Growth predictors and prognosis of small abdominal aortic aneurysms

Felix Jv Schlösser; Marco J.D. Tangelder; Hence J.M. Verhagen; Geert J. M. G. van der Heijden; Bart E. Muhs; Yolanda van der Graaf; Frans L. Moll

OBJECTIVE Evidence regarding the influence of cardiovascular risk factors, comorbidities, and patient characteristics on the growth of small abdominal aortic aneurysms (AAA) is limited. We assessed, in an observational cohort study, rupture rates, risks of mortality, and the effects of cardiovascular risk factors and patient demographics on growth rates of small AAAs. METHODS Between September 1996 and January 2005, 5057 patients with manifest arterial vascular disease or cardiovascular risk factors were included in the Second Manifestation of ARTerial disease (SMART) study. Measurements of the abdominal aortic diameter were performed in all patients. All patients with an initial AAA diameter between 30 and 55 mm were selected for this study. All AAA measurements during follow-up until August 2007 were collected. Multivariate regression analysis was performed to calculate the effects of demographic patient characteristics, initial AAA diameter, and cardiovascular risk factors on AAA growth. RESULTS Included were 230 patients, with a mean age of 66 years and 90% were male. Seven AAA ruptures (six fatal) occurred in 755 patient years of follow-up (rupture rate 0.9% per patient-year). In 147 patients, AAA measurements were performed for a period of more than 6 months. The median follow-up time was 3.3 years (mean 4.0, range 0.5 to 11.1 years, standard deviation (SD) 2.5). Mean AAA diameter was 38.8 mm (SD 6.8) and mean expansion rate 2.5 mm/y. Patients using lipid-lowering drugs had a 1.2 mm/y (95% confidence interval [CI] -2.34 to -0.060 mm/y) lower AAA growth rate compared to nonusers of these drugs. Initial AAA diameter was associated with a 0.09 mm/y (95% CI 0.01 to 0.18 mm/y) higher growth rate per millimetre increase of the diameter. No other factors, including blood lipid values, were independently associated with AAA growth. CONCLUSIONS Lipid-lowering drug treatment and initial AAA diameter appear to be independently associated with lower AAA growth rates. The risk of rupture of these small abdominal aortic aneurysms was low, which pleads for watchful waiting.


Circulation | 1999

Health-related quality of life after angioplasty and stent placement in patients with iliac artery occlusive disease: Results of a randomized controlled clinical trial

Johanna L. Bosch; Yolanda van der Graaf; M. G. Myriam Hunink

Backround —To assess the quality of life in patients with iliac artery occlusive disease, we compared primary stent placement versus primary angioplasty followed by selective stent placement in a multicenter randomized controlled trial. Methods and Results —Quality-of-life assessments were completed by 254 patients in a telephone interview. Assessment measures consisted of the RAND 36-Item Health Survey 1.0, time tradeoff, standard gamble, rating scale, health utilities index, and EuroQol-5D. The interviews were performed before treatment and after 1, 3, 12, and 24 months. When the 2 treatments were compared, no significant difference was observed ( P >0.05). All measurements showed a significant improvement in the quality of life after treatment ( P Conclusions —Health-related quality of life improves equally after primary stent placement and primary angioplasty with selective stent placement in the treatment of intermittent claudication caused by iliac artery occlusive disease.

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