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Dive into the research topics where Martijn C. Post is active.

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Featured researches published by Martijn C. Post.


Neurology | 2004

Closure of a patent foramen ovale is associated with a decrease in prevalence of migraine

Martijn C. Post; Vincent Thijs; Luc Herroelen; Werner Budts

A patent foramen ovale (PFO) is one of the major causes of right-to-left shunt, and a causal relationship between migraine and a PFO has been suggested.1 We evaluated whether percutaneous closure of a PFO was associated with changes in the prevalence of migraine. ### Patient selection. Patients with a PFO who had a paradoxical embolic event or systemic desaturation and who underwent a percutaneous closure in our center between February 1999 and September 2002 were included. The medical files were reviewed. The ethical committee approved the study. ### Evaluation of migraine. A questionnaire was composed in such a way that a neurologist could diagnose migraine with or without aura (MA+ and MA−) according to the criteria of the International Headache Society. The questionnaire was sent to all patients and focused on three periods: 1 year before and 2 months and at least 6 months after percutaneous closure. Two neurologists blinded to the patients’ files diagnosed MA+ …


Neurology | 2006

Embolization of pulmonary arteriovenous malformations and decrease in prevalence of migraine

Martijn C. Post; Vincent Thijs; Wouter J. Schonewille; Werner Budts; Roel J.R. Snijder; Herbert W.M. Plokker; Cornelis J.J. Westermann

Objective: To determine if embolization of pulmonary arteriovenous malformations (PAVMs) decreases the occurrence of migraine. Methods: All 105 patients with hereditary hemorrhagic telangiectasia (HHT), minimum age 16 years, who underwent an embolization of PAVM in our hospital between June 1995 and April 2004, were included in this study. A structured headache questionnaire was sent to all patients and focused on two periods: 1 year before and at least 6 months after embolization. Two independent neurologists diagnosed migraine according to the International Headache Society criteria. Results: Eighty-four patients (80%) sent back the questionnaire (mean age 47.8 ± 15.1 years, 51 female). Median follow-up time was 48 months (first quartile: 23 months; third quartile: 66 months). The overall prevalence of migraine decreased from 45.2% before to 34.5% after embolization (p = 0.01). The prevalence of migraine with aura decreased from 33.3% before to 19.0% after embolization (p = 0.002). The severity of headache attacks decreased in patients who still had migraine (p = 0.15) or migraine with aura after embolization (p = 0.11). Conclusion: Embolization of pulmonary arteriovenous malformations in patients with hereditary hemorrhagic telangiectasia seems to be related to a decrease in prevalence of migraine, suggesting that the presence of a right-to-left shunt rather than the localization of this shunt plays a causative role in the pathogenesis of migraine.


European Respiratory Journal | 2009

Screening for pulmonary arteriovenous malformations using transthoracic contrast echocardiography: a prospective study

M. W. F. van Gent; Martijn C. Post; J.G.L.M. Luermans; Roel J.R. Snijder; Cornelis J.J. Westermann; Herbert W.M. Plokker; T. T. Overtoom; Johannes J. Mager

Pulmonary arteriovenous malformations (PAVMs) are associated with severe neurological complications in patients with hereditary haemorrhagic telangiectasia (HHT). The objective of the present study was to prospectively establish the diagnostic value of transthoracic contrast echocardiography (TTCE) as a screening technique for PAVM using chest high-resolution computed tomography (HRCT) as the gold standard for PAVMs. All consecutive adult patients referred for HHT screening underwent a chest HRCT (n = 299), TTCE (n = 281), arterial blood gas analysis (n = 291), shunt fraction measurement (n = 111) and chest radiography (n = 296). TTCE was positive in 87 (58.8%), 12 (16.7%) and four (6.7%) patients, and chest HRCT was positive in 54 (36.5%), three (4.2%) and zero (0%) patients with a definite, possible and negative clinical diagnosis of HHT, respectively. Two patients with a negative TTCE were diagnosed with PAVMs after computed tomography; in both cases the PAVMs were too small to be treated by embolotherapy. The sensitivity of TTCE was 97% (95% confidence interval (CI) 93.6–98.3) and negative predictive value 99% (95% CI 96.9–99.8). The other diagnostic tests showed a considerable lower diagnostic value. The present prospective study shows that transthoracic contrast echocardiography has an excellent diagnostic value and can be used as an initial screening procedure for pulmonary arteriovenous malformations. The high false-positive rate of transthoracic contrast echocardiography possibly represents microscopic pulmonary arteriovenous malformations.


Acta Cardiologica | 2005

Percutaneous closure of a patent foramen ovale: single-centre experience using different types of devices and mid-term outcome.

Martijn C. Post; Kristien Van Deyk; Werner Budts

Introduction — Patent foramen ovale (PFO) has been identified as a source of paradoxical embolism and cryptogenic stroke. Low recurrence rates of ischaemic stroke after percutaneous closure have been described.We report our single-centre experience using four different types of devices. Methods — All patients, who underwent a percutaneous PFO closure in the University Hospitals Leuven between February 1999 and December 2003, were included. The primary end point was defined as reoccurrence of stroke, transient ischaemic attack (TIA), or a peripheral thrombo-embolic event.The periprocedural and mid-term complications were reported. Results — One-hundred and twelve patients, mean age 52.1 ± 12.5 years (63 men/49 women), were included in the study. Indications for closure were cryptogenic stroke (91.9%), peripheral embolism (4.5%), obligate right-to-left shunt in Ebstein anomaly (1.8%), platypnoea syndrome or brain abscesses (both 0.9%).The Cardioseal/Starflex® was used in 12, the Amplatzer PFO occluder® in 35, the PFOStar/CardiaStar® in 64, and the Helex® in one patient.The primary end point occurred in 1.8% for stroke and 2.8% for TIA during a median follow-up of 1.9 years, range 4.9 years. Periprocedural complications were dislocation of the device (0.9%), transient arrhythmias (15.5%), aspiration pneumonia (0.9%), inguinal haematoma (3.6%), and an allergic reaction to medication (1.8%). Mid-term complications were perforation of the device (0.9%), persistent transient arrhythmias (6.3%) and thrombus formation on the device (0.9%). No significant differences in outcome or the occurrence of any type of complication could be documented between the different types of devices. Conclusion — Percutaneous PFO closure seems to be a highly efficient and relatively safe procedure, independent of the type of device used for closure.


European Journal of Echocardiography | 2009

Three-dimensional transoesophageal echocardiography in a patient undergoing percutaneous mitral valve repair using the edge-to-edge clip technique

Martin J. Swaans; B. J. L. Van den Branden; J. A. S. van der Heyden; Martijn C. Post; Benno J. Rensing; Frank D. Eefting; H. W. M. Plokker; Wybren Jaarsma

We report a case of percutaneous mitral valve repair, using the Mitraclip device, in which we show that application of real-time three-dimensional transoesophageal echocardiography (3D-TEE) is extremely helpful for the guidance of this procedure. Because of its excellent visualization capacities, 3D-TEE simplifies the transseptal puncture, the positioning of the clip above the mitral valve orifice, the grasping of the mitral valve leaflets, and the evaluation of the final result. Therefore, we conclude that 3D-TEE has the potential to increase the safety and efficacy of this new technique to treat mitral regurgitation in patients who cannot undergo conventional valve surgery.


Jacc-cardiovascular Interventions | 2014

Survival of Transcatheter Mitral Valve Repair Compared With Surgical and Conservative Treatment in High-Surgical-Risk Patients

Martin J. Swaans; Annelies L.M. Bakker; Arash Alipour; Martijn C. Post; Johannes C. Kelder; Thom de Kroon; Frank D. Eefting; Benno J. Rensing; Jan Van der Heyden

OBJECTIVES The goal of this study was to compare survival between transcatheter mitral valve (MV) repair using MitraClip system (Abbott Vascular, Santa Clara, California), MV-surgery, and conservative treatment in high-surgical-risk patients symptomatic with severe mitral valve regurgitation (MR). BACKGROUND Up to 50% of patients with symptomatic severe MR are denied for surgery due to high perioperative risk. Transcatheter MV repair might be an alternative. METHODS Consecutive patients (n = 139) treated with transcatheter MV repair were included. Comparator surgically (n = 53) and conservatively (n = 59) treated patients were identified retrospectively. Surgical risk was based on the logistic European System for Cardiac Operative Risk Evaluation (log EuroSCORE) or the presence of relevant risk factors, as judged by the heart team. RESULTS The log EuroSCORE was higher in the transcatheter MV repair group (23.9 ± 16.1%) than in the surgically (14.2 ± 8.9%) and conservatively (18.7 ± 13.2%, p < 0.0001) treated patients. Left ventricular ejection fraction was higher in surgical patients (43.9 ± 14.4%, p = 0.003), with similar values for the transcatheter MV repair (36.8 ± 15.3%) and conservatively treated (34.5 ± 16.5%) groups. After 1 year of follow-up, the transcatheter MV repair and surgery groups showed similar survival rates (85.8% and 85.2%, respectively), whereas 67.7% of conservatively treated patients survived. The same trend was observed after the second and third years. After weighting for propensity score and controlling for risk factors, both the transcatheter MV repair (hazard ratio [HR]: 0.41, 95% confidence interval [CI]: 0.22 to 0.78, p = 0.006) and surgical (HR: 0.52, 95% CI: 0.30 to 0.88, p = 0.014) groups showed better survival than the conservatively treated group. The transcatheter MV repair and surgical groups did not differ (HR: 1.25, 95% CI: 0.72 to 2.16, p = 0.430). CONCLUSIONS Despite a higher log EuroSCORE, high-surgical-risk patients with symptomatic severe MR treated with transcatheter MV repair show similar survival rates compared with surgically treated patients, with both displaying survival benefit compared with conservative treatment.


Chest | 2010

Real Prevalence of Pulmonary Right-to-Left Shunt According to Genotype in Patients With Hereditary Hemorrhagic Telangiectasia: A Transthoracic Contrast Echocardiography Study

Marco W.F. van Gent; Martijn C. Post; Repke J. Snijder; Cornelis J.J. Westermann; Herbert W.M. Plokker; Johannes J. Mager

BACKGROUND Transthoracic contrast echocardiography (TTCE) can detect pulmonary right-to-left shunting (RLS) and is used to screen for pulmonary arteriovenous malformations (PAVMs) in patients with hereditary hemorrhagic telangiectasia (HHT). We studied the prevalence and size of pulmonary RLS in HHT type 1, HHT type 2, and HHT-negative controls, and its positive predictive value (PPV) and negative predictive value (NPV) for PAVMs that can be treated by embolotherapy. METHODS In 343 consecutive persons referred for possible HHT as first-degree family members of index patients a TTCE and chest CT scan were performed. All persons were offered genetic analysis. RESULTS An HHT-causing mutation was confirmed in 92 (mean age 41 ± 15 y; 59% female) HHT1 relatives and in 97 (mean age 47 ± 14 y; 52% female) HHT2 relatives. TTCE showed a pulmonary RLS in 78 (85%) HHT1- and 34 (35%) HHT2-related mutation carriers, respectively (P < .0001). In HHT1 relatives, 29 of 53 (55%) PAVMs and in HHT2 relatives three of 17 (18%) PAVMS were treated, resulting in a PPV of TTCE for treatable PAVMs of 36.3% and 8.3%, respectively. The accompanying NPV was 100%. A minimal, moderate, or large shunt was present in 12 (13%), 24 (26%), and 42 (46%) HHT1-related, and in 20 (21%), 6 (6%), and 8 (8%) HHT2-related mutation carriers, respectively (P for trend < .0001). A large shunt predicted treatable PAVMs in 55.8% of HHT1 relatives and 37.5% of HHT2 relatives. TTCE was positive in four (6%) of 63 persons without HHT. CONCLUSIONS A pulmonary shunt on TTCE is more prevalent and larger in HHT1- compared with HHT2-related mutation carriers. Shunt grading is helpful to predict treatable PAVMs, particularly in the HHT2 group. TTCE is also positive in a small fraction of persons without HHT.


Chest | 2009

Grading of Pulmonary Right-to-Left Shunt With Transthoracic Contrast Echocardiography: Does It Predict the Indication for Embolotherapy?

Marco W.F. van Gent; Martijn C. Post; Repke J. Snijder; Martin J. Swaans; Herbert W.M. Plokker; Cornelis J.J. Westermann; Tim T. Overtoom; Johannes J. Mager

RATIONALE Pulmonary arteriovenous malformations (PAVMs) are associated with severe neurologic complications in patients with hereditary hemorrhagic telangiectasia (HHT). Therefore, screening is warranted. Transthoracic contrast echocardiography (TTCE) can effectively detect a pulmonary right-to-left shunt (RLS). OBJECTIVES To determine prospectively the predictive value of TTCE grading to detect PAVMs on high-resolution CT (HRCT) scans of the chest and the indication for embolotherapy. METHODS Three hundred seventeen patients, referred for possible HHT, were screened for PAVMs. Patients who underwent both chest HRCT scanning and TTCE were included in the study (n = 281). For the purposes of this study we used a 3-point grading scale, and shunt grades 3 and 4 according to the classification model of Barzilai et al were combined. Embolotherapy was performed of all PAVMs judged large enough for treatment. RESULTS Echocardiographic criteria for a pulmonary RLS were present in 105 patients (41%) [mean (+/- SD) age, 43.7 +/- 15.7 years; female gender, 63%]. Chest HRCT scan findings were positive in 55 patients (52%) in this group. The positive predictive value of shunt grade for the presence of PAVMs on chest HRCT scans was 22.9% for grade 1 (n = 35), 34.8% for grade 2 (n = 23), and 83.0% for grade 3 (n = 47), respectively. None of the patients with PAVMs seen on chest HRCT scans and a TTCE grade 1 (n = 8) or 2 (n = 8) were candidates for embolotherapy. Of 39 patients with TTCE grade 3 and PAVMs seen on chest HRCT scans, 26 patients (67%) underwent embolotherapy. CONCLUSION An increased echocardiographic shunt grade correlates with an increased probability of PAVMs seen on chest HRCT scans. Only patients with a TTCE grade 3 displayed PAVMs on chest HRCT scans that were large enough for embolotherapy.


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.


Jacc-cardiovascular Interventions | 2012

Percutaneous edge-to-edge mitral valve repair in high-surgical-risk patients: do we hit the target?

Ben J.L. Van den Branden; Martin J. Swaans; Martijn C. Post; Benno J. Rensing; Frank D. Eefting; Wybren Jaarsma; Jan Van der Heyden

OBJECTIVES This study sought to assess the feasibility and safety of percutaneous edge-to-edge mitral valve (MV) repair in patients with an unacceptably high operative risk. BACKGROUND MV repair for mitral regurgitation (MR) can be accomplished by use of a clip that approximates the free edges of the mitral leaflets. METHODS All patients were declined for surgery because of a high logistic EuroSCORE (>20%) or the presence of other specific surgical risk factors. Transthoracic echocardiography was performed before and 6 months after the procedure. Differences in New York Heart Association (NYHA) functional class, quality of life (QoL) using the Minnesota questionnaire, and 6-min walk test (6-MWT) distances were reported. RESULTS Fifty-five procedures were performed in 52 patients (69.2% male, age 73.2 ± 10.1 years, logistic EuroSCORE 27.1 ± 17.0%). In 3 patients, partial clip detachment occurred; a second clip was placed successfully. One patient experienced cardiac tamponade. Two patients developed inguinal bleeding, of whom 1 needed surgery. Six patients (11.5%) died during 6-month follow-up (5 patients as a result of progressive heart failure and 1 noncardiac death). The MR grade before repair was ≥3 in 100%; after 6 months, a reduction in MR grade to ≤2 was present in 79% of the patients. Left ventricular (LV) end-diastolic diameter, LV ejection fraction, and systolic pulmonary artery pressure improved significantly. Accompanied improvements in NYHA functional class, QoL index, 6-MWT distances, and log N-terminal pro-B-type natriuretic peptide were observed. CONCLUSIONS In a high-risk population, MR reduction can be achieved by percutaneous edge-to-edge valve repair, resulting in LV remodeling with improvement of functional capacity after 6 months.

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Werner Budts

Katholieke Universiteit Leuven

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Benno J. Rensing

Erasmus University Rotterdam

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Vincent Thijs

Florey Institute of Neuroscience and Mental Health

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Justin G.L.M. Luermans

Maastricht University Medical Centre

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