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Dive into the research topics where Sebastiaan Velthuis is active.

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Featured researches published by Sebastiaan Velthuis.


Arthritis & Rheumatism | 2010

Cardiac involvement in Churg‐Strauss syndrome

Robert Dennert; Pieter van Paassen; Simon Schalla; Tatiana Kuznetsova; Becker S. N. Alzand; Jan A. Staessen; Sebastiaan Velthuis; Harry J.G.M. Crijns; Jan Willem Cohen Tervaert; Stephane Heymans

OBJECTIVE Churg-Strauss syndrome (CSS) is a rare form of systemic vasculitis. Previous studies showing cardiac involvement in CSS patients were limited in the number of patients and were often based solely on clinical manifestations. The aim of the present study was to determine in detail the incidence of cardiac involvement in a large population of ambulatory CSS patients. METHODS Thirty-two consecutive patients with CSS in remission (mean +/- SD duration of disease between diagnosis and enrollment 6.1 +/- 5.8 years, mean +/- SD age 61 +/- 10 years) who were previously unaware of cardiac involvement were compared with 32 randomly selected age- and sex-matched control subjects, using clinical evaluation, electrocardiography (EKG), echocardiography, and cardiac magnetic resonance imaging (MRI). RESULTS Detailed cardiac evaluation revealed a 62% prevalence of cardiac involvement in CSS patients compared with 3% in controls (P < 0.001), with clinical symptoms in 26% and 3%, respectively (P = 0.009), EKG abnormalities in 66% and 3%, respectively (P < 0.001), and echocardiographic defects in 50% and 3%, respectively (P < 0.001). Cardiac MRI detected cardiac manifestations in 62% of CSS patients. In the presence of cardiac MRI abnormalities, echocardiography could detect cardiac involvement with a sensitivity of 83% and a specificity of 80%. The absence of symptoms or EKG abnormalities did not exclude cardiac involvement, because abnormalities could still be detected in 38% of these patients at the time of echocardiography or cardiac MRI. CONCLUSION These results demonstrate a high incidence of cardiac involvement in CSS patients. Systematic cardiac evaluation including detailed imaging is required to properly identify CSS patients with cardiac involvement.


Antiviral Therapy | 2010

Intravenous immunoglobulin therapy for patients with idiopathic cardiomyopathy and endomyocardial biopsy-proven high PVB19 viral load.

Robert Dennert; Sebastiaan Velthuis; Simon Schalla; Luc W. Eurlings; Robert-Jan van Suylen; Pieter van Paassen; Jan William Cohen Tervaert; Petra F. G. Wolffs; Valère J. Goossens; C.A. Bruggeman; Johannes Waltenberger; Harry J.G.M. Crijns; Stephane Heymans

BACKGROUND Parvovirus B19 (PVB19) persistence in the heart has been associated with progressive cardiac dysfunction and evolution to dilated cardiomyopathy. In the present study, we investigated whether immunomodulation with intravenous immunoglobulin (IVIg) in addition to conventional heart failure therapy is safe and achieves virus reduction. Such therapy might improve cardiac function in patients with chronic dilated cardiomyopathy (DCM) and a significant PVB19 viral load in the heart. METHODS PVB19 viral load was studied in 25 post-mortem cardiac samples of patients with a normal heart. Then, 17 consecutive patients (mean age 53 +/-3 years) with DCM and symptomatic heart failure for >1 year with a PVB19 viral load in endomyocardial biopsies of >250 copies/microg DNA were treated with a high dose of IVIg (2 g/kg). RESULTS The post-mortem cardiac samples revealed a PVB19 presence in 80% with a mean load of 131 +/-40 copies/microg DNA. In the treated patients, IVIg resulted in a significant decrease of PVB19 viral load from 1,420 +/-216 to 619 +/-200 copies/microg DNA (P=0.004) and significantly improved the ejection fraction from 33 +/-3% 6 months before treatment and 34 +/-3% at baseline to 41 +/-3% 6 months (P=0.001) after IVIg therapy. The New York Heart Association classification significantly improved from 2.5 +/-0.1 at baseline to 2.1 +/-0.1 at follow-up (P=0.004). No therapy-related complications were noted. CONCLUSIONS The present pilot study demonstrates that IVIg significantly reduces viral load and improves cardiac function in patients with DCM related to increased PVB19 viral load in the heart.


Chest | 2013

Grade of pulmonary right-to-left shunt on contrast echocardiography and cerebral complications: a striking association.

Sebastiaan Velthuis; Elisabetta Buscarini; Marco W.F. van Gent; Pietro Gazzaniga; Guido Manfredi; Cesare Danesino; Wouter J. Schonewille; Cornelis J.J. Westermann; Repke J. Snijder; Johannes J. Mager; Martijn C. Post

BACKGROUND A pulmonary right-to-left shunt (RLS) carries the risk of cerebral paradoxical embolization and severe neurologic complications. Recognizing patients at risk is important to facilitate appropriate management strategies, but a direct relation between pulmonary shunt size and risk of complications remains controversial. This study evaluated the potential relation between pulmonary shunt grade on transthoracic contrast echocardiography (TTCE) and prevalence of cerebral manifestations in patients screened for hereditary hemorrhagic telangiectasia (HHT). METHODS We conducted a two-center, cross-sectional study of all consecutive patients screened for HHT between 2004 and 2011. Pulmonary shunt grading on TTCE (grade 0, no microbubbles; grade 1, < 30 microbubbles; grade 2, 30-100 microbubbles; grade 3, > 100 microbubbles) was performed according to contrast opacification of the left ventricle. Cerebral complications were defined as ischemic stroke, transient ischemic attack, or brain abscess diagnosed by a neurologist and confirmed by appropriate imaging techniques. RESULTS A pulmonary RLS was present in 530 out of 1,038 patients (51.1%; mean age, 44.3 ± 15.6 years; 58.6% women). The presence of a cerebral manifestation (n = 51) differed significantly among pulmonary shunt grades on TTCE: 1.4%, 0.4%, 6.5%, and 20.9% for grades 0, 1, 2 and 3, respectively. A pulmonary shunt grade 1 was not associated with an increased prevalence of cerebral manifestations (OR, 0.44; 95% CI, 0.05-4.13; P = .47), whereas pulmonary shunt grade 2 (OR, 4.78; 95% CI, 1.14-20.0; P = .03) and grade 3 (OR, 10.4; 95% CI, 2.4-45.3; P = .002) were both independent predictors for the prevalence of a cerebral ischemic event or brain abscess. CONCLUSIONS The pulmonary RLS grade on TTCE is strongly associated with the prevalence of cerebral complications in patients screened for HHT.


Chest | 2013

Original ResearchPulmonary Vascular DiseaseGrade of Pulmonary Right-to-Left Shunt on Contrast Echocardiography and Cerebral Complications: A Striking Association

Sebastiaan Velthuis; Elisabetta Buscarini; Marco W.F. van Gent; Pietro Gazzaniga; Guido Manfredi; Cesare Danesino; Wouter J. Schonewille; Cornelis J.J. Westermann; Repke J. Snijder; Johannes J. Mager; Martijn C. Post

BACKGROUND A pulmonary right-to-left shunt (RLS) carries the risk of cerebral paradoxical embolization and severe neurologic complications. Recognizing patients at risk is important to facilitate appropriate management strategies, but a direct relation between pulmonary shunt size and risk of complications remains controversial. This study evaluated the potential relation between pulmonary shunt grade on transthoracic contrast echocardiography (TTCE) and prevalence of cerebral manifestations in patients screened for hereditary hemorrhagic telangiectasia (HHT). METHODS We conducted a two-center, cross-sectional study of all consecutive patients screened for HHT between 2004 and 2011. Pulmonary shunt grading on TTCE (grade 0, no microbubbles; grade 1, < 30 microbubbles; grade 2, 30-100 microbubbles; grade 3, > 100 microbubbles) was performed according to contrast opacification of the left ventricle. Cerebral complications were defined as ischemic stroke, transient ischemic attack, or brain abscess diagnosed by a neurologist and confirmed by appropriate imaging techniques. RESULTS A pulmonary RLS was present in 530 out of 1,038 patients (51.1%; mean age, 44.3 ± 15.6 years; 58.6% women). The presence of a cerebral manifestation (n = 51) differed significantly among pulmonary shunt grades on TTCE: 1.4%, 0.4%, 6.5%, and 20.9% for grades 0, 1, 2 and 3, respectively. A pulmonary shunt grade 1 was not associated with an increased prevalence of cerebral manifestations (OR, 0.44; 95% CI, 0.05-4.13; P = .47), whereas pulmonary shunt grade 2 (OR, 4.78; 95% CI, 1.14-20.0; P = .03) and grade 3 (OR, 10.4; 95% CI, 2.4-45.3; P = .002) were both independent predictors for the prevalence of a cerebral ischemic event or brain abscess. CONCLUSIONS The pulmonary RLS grade on TTCE is strongly associated with the prevalence of cerebral complications in patients screened for HHT.


Journal of The American Society of Echocardiography | 2015

Clinical implications of pulmonary shunting on saline contrast echocardiography.

Sebastiaan Velthuis; Elisabetta Buscarini; James R. Gossage; Repke J. Snijder; Johannes J. Mager; Martijn C. Post

Pulmonary right-to-left shunting can be encountered using transthoracic contrast echocardiography (TTCE) with agitated saline. Diseases associated with pulmonary shunting on saline TTCE include hereditary hemorrhagic telangiectasia (HHT), hepatopulmonary syndrome, and some congenital heart defects after partial or complete cavopulmonary anastomosis. Furthermore, small pulmonary shunts on saline TTCE are also documented in a proportion of healthy individuals. Pulmonary shunting carries the risk for severe neurologic complications due to paradoxical embolization. In HHT, additional chest computed tomography is recommended in case of any pulmonary shunt detected on saline TTCE, to evaluate the feasibility for transcatheter embolotherapy of pulmonary arteriovenous malformations. Furthermore, antibiotic prophylaxis is advised in case of any pulmonary shunt on saline TTCE to prevent brain abscesses after procedures with risk for bacteremia. The present review provides an overview of important aspects of pulmonary shunting and its detection using saline TTCE. Furthermore, advances in understanding the clinical implications of different pulmonary shunt grades on saline TTCE are described. It appears that small pulmonary shunts on saline TTCE (grade 1) lack any clinical implication, as these shunts cannot be used as a diagnostic criterion for HHT, are not associated with an increased risk for neurologic complications, and represent pulmonary arteriovenous malformations too small for subsequent endovascular treatment. This implies that additional chest computed tomography could be safely withheld in all persons with only small pulmonary shunts on saline TTCE and sets the stage for further discussion about the need for antibiotic prophylaxis in these subjects. Besides further optimization of the current screening algorithm for the detection of pulmonary arteriovenous malformations in HHT, these observations can be of additional clinical importance in other diseases associated with pulmonary shunting and in those healthy individuals with documented small pulmonary shunts on saline TTCE.


European Respiratory Journal | 2014

Predicting the size of pulmonary arteriovenous malformations on chest computed tomography: a role for transthoracic contrast echocardiography

Sebastiaan Velthuis; Elisabetta Buscarini; Johannes J. Mager; Veronique M.M. Vorselaars; Marco W.F. van Gent; Pietro Gazzaniga; Guido Manfredi; Cesare Danesino; Arjen L. Diederik; Jan A. Vos; Silvia Gandolfi; Repke J. Snijder; Cornelis J.J. Westermann; Martijn C. Post

This study aimed to investigate whether pulmonary shunt grade on transthoracic contrast echocardiography (TTCE) predicts the size of pulmonary arteriovenous malformations (PAVMs) on chest computed tomography (CT) and subsequent feasibility for transcatheter embolotherapy. We prospectively included 772 persons with possible or definite hereditary haemorrhagic telangiectasia, who underwent both TTCE and chest CT for screening of PAVMs. A quantitative three-point grading scale was used to classify the pulmonary shunt size on TTCE (grade 1–3). Transcatheter embolotherapy was performed for PAVMs deemed large enough for endovascular closure on chest CT. TTCE documented pulmonary shunting in 510 (66.1%) patients. The positive predictive value of a pulmonary shunt grade 1, 2 and 3 on TTCE for presence of PAVMs on chest CT was 13.4%, 45.3% and 92.5%, respectively (p<0.001). None of the 201 persons with a pulmonary shunt grade 1 on TTCE had PAVMs on chest CT large enough for transcatheter embolotherapy, while 38 (25.3%) and 123 (77.4%) individuals with a pulmonary shunt grade 2 and 3 on TTCE, respectively, underwent endovascular closure of PAVMs. Pulmonary shunt grade on TTCE predicts the size of PAVMs on chest CT and their feasibility for subsequent transcatheter embolotherapy. Chest CT can be safely withheld from all persons with a pulmonary shunt grade 1 on TTCE, as any PAVM found in these subjects will be too small for transcatheter embolotherapy. Chest CT can be safely withheld from persons with pulmonary shunt grade 1 on TTCE http://ow.ly/sUAps


American Journal of Medical Genetics Part A | 2013

Hereditary hemorrhagic telangiectasia: how accurate are the clinical criteria?

Marco W.F. van Gent; Sebastiaan Velthuis; Martijn C. Post; Repke J. Snijder; Cornelis J.J. Westermann; Tom G. W. Letteboer; Johannes J. Mager

The clinical diagnosis of hereditary hemorrhagic telangiectasia (HHT) is based on the Curaçao criteria. Three out of four criteria are required for a definite clinical diagnosis HHT, two criteria are considered “possible” HHT, and 0 or 1 criterion makes the diagnosis unlikely. However, these consensus diagnostic criteria have not been validated. We report on the diagnostic accuracy of the clinical criteria. A total of 450 consecutive persons ≥16 years of age were screened for HHT between May 2004 and September 2009, including a chest CT to screen for pulmonary arteriovenous malformations (AVMs). We selected 263 first‐degree relatives of disease‐causing mutation carriers who underwent mutation analysis. Genetic test results were considered the gold standard. The family mutation was present in 186 patients (mean age 42.9 ± 14.6 yr; 54.8% female). A clinical diagnosis was definite, “possible”, and unlikely in 168 (90.3%), 17 (9.1%), and 1 (0.5%) patient, respectively. In 77 persons the family mutation was absent (mean age 37.1 ± 12.3 yr, 59.7% female). In this group a clinical diagnosis was definite, possible, and unlikely in 0, 35 (45.5%), and 42 (54.5%) persons, respectively. The positive predictive value of a definite clinical diagnosis was 100% (95% CI 97.8–100), the negative predictive value of an unlikely diagnosis 97.7% (95% CI 87.9–99.6). Of 52 patients with “possible” HHT, 17 (32.7%) displayed an HHT‐causing mutation. The Curaçao clinical criteria have a good diagnostic performance. Genetic testing is particularly helpful in patients with a “possible” clinical diagnosis HHT.


World Journal of Cardiology | 2015

Pulmonary hypertension in hereditary haemorrhagic telangiectasia

Veronique M.M. Vorselaars; Sebastiaan Velthuis; Repke J. Snijder; Jan A. Vos; Johannes J. Mager; Martijn C. Post

Hereditary haemorrhagic telangiectasia (HHT) is an autosomal dominant inherited disorder characterised by vascular malformations in predominantly the brain, liver and lungs. Pulmonary hypertension (PH) is increasingly recognised as a severe complication of HHT. PH may be categorised into two distinct types in patients with HHT. Post-capillary PH most often results from a high pulmonary blood flow that accompanies the high cardiac output state associated with liver arteriovenous malformations. Less frequently, the HHT-related gene mutations in ENG or ACVRL1 appear to predispose patients with HHT to develop pre-capillary pulmonary arterial hypertension. Differentiation between both forms of PH by right heart catheterisation is essential, since both entities are associated with severe morbidity and mortality with different treatment options. Therefore all HHT patients should be referred to an HHT centre.


Chest | 2013

Role of Transthoracic Contrast Echocardiography in the Clinical Diagnosis of Hereditary Hemorrhagic Telangiectasia

Sebastiaan Velthuis; Veronique M.M. Vorselaars; Marco W.F. van Gent; Cornelis J.J. Westermann; Repke J. Snijder; Johannes J. Mager; Martijn C. Post

BACKGROUND Hereditary hemorrhagic telangiectasia (HHT) can be diagnosed according to the four clinical Curaçao criteria, including the presence of pulmonary arteriovenous malformations (PAVMs). In the past few years, transthoracic contrast echocardiography (TTCE) replaced chest high-resolution CT (HRCT) imaging for the screening of PAVMs. The objective of this study was to determine whether the presence of any pulmonary shunt on TTCE can be accepted as a new clinical Curaçao criterion in diagnosing HHT. METHODS Between 2004 and 2012, we included 487 first-degree relatives of known HHT-causing mutation carriers who underwent both TTCE and chest HRCT imaging to screen for PAVMs. A quantitative three-point grading scale was used to differentiate among minimal, moderate, or extensive pulmonary shunt on TTCE (grade 1-3). Genetic testing was performed in all people and considered the gold standard for the diagnosis of HHT. RESULTS Chest HRCT imaging demonstrated PAVMs in 114 of 218 patients (52.3%) with a pulmonary shunt on TTCE. The addition of any pulmonary shunt on TTCE to the current clinical Curaçao criteria increased the number of positive criteria in 92 of 487 individuals (18.9%), which increased the sensitivity in diagnosing HHT from 88% to 94% at the expense of a decreased specificity from 74% to 70%. Accepting only pulmonary shunt grades ≥ 2 on TTCE as a diagnostic criterion for HHT enhanced the number of positive criteria in 30 (6.2%) individuals, which led to an increased sensitivity of 90% with no decrease in specificity (74%). CONCLUSIONS The addition of only pulmonary shunt grades ≥ 2 on TTCE to the current clinical Curaçao criteria increases its sensitivity without affecting specificity in the diagnosis of HHT.


Clinical and Vaccine Immunology | 2012

Differences in Virus Prevalence and Load in the Hearts of Patients with Idiopathic Dilated Cardiomyopathy with and without Immune-Mediated Inflammatory Diseases

Robert Dennert; Pieter van Paassen; Petra F. G. Wolffs; C.A. Bruggeman; Sebastiaan Velthuis; Susanne Felix; Robert-Jan van Suylen; Harry J. Crijns; Jan Willem Cohen Tervaert; Stephane Heymans

ABSTRACT Infections with cardiotrophic viruses and immune-mediated responses against the heart have been suggested to play a dominant role in the pathogenesis of idiopathic dilated cardiomyopathy (DCM). Furthermore, immune-mediated inflammatory diseases (IMIDs) may result in DCM. It has not previously been assessed whether DCM patients with and without an IMID have different prevalences and quantities of cardiotrophic viruses in the heart. Therefore, we compared the profiles of cardiotrophic viruses in heart tissue of DCM patients with and without an IMID. Serum and myocardial tissue samples were obtained from 159 consecutive patients with DCM and 20 controls. Patients were subdivided into three groups, the first two based on the presence (n = 34) or absence (n = 125) of an IMID and the third being a control group. The parvovirus B19 virus genome was detected in equal quantities in the non-IMID DCM patients (100/125) and the control group (15/20) but in lower quantities in the IMID patients (21/34, P = 0.02). Both the non-IMID and IMID DCM patients demonstrated increased myocardial inflammation compared to controls: 12.5 ± 1.8 and 14.0 ± 3.2 CD45-positive inflammatory cells, respectively, versus 5.1 ± 0.7 for the controls (P < 0.05 for both). Importantly, significantly higher parvovirus B19 copy numbers could be amplified in non-IMID than in IMID patients (561 ± 97 versus 191 ± 92 copies/μg DNA, P < 0.001) and control subjects (103 ± 47 copies/μg DNA, P < 0.001). The present study shows decreased parvovirus B19 prevalence and copy numbers in hearts of DCM patients with an IMID compared to those without an IMID. These findings may suggest that DCM patients with an IMID have a different pathophysiologic mechanism from that which is present in the virus-induced form of DCM.

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Martijn C. Post

Katholieke Universiteit Leuven

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