Karl Dujardin

• Doctor of Medicine
• Head of Department at AZ Delta

Background As cardiac catheterization operators are exposed to radiation exposure throughout their careers, optimal radiation protection is crucial. Our study was designed to assess the effects of supplementary protective measures beyond standard radiation protection attire and barriers, measuring their influence on scatter radiation exposure level...

Background: One third of patients undergoing transcatheter aortic-valve implantation (TAVI) have an indication for oral anticoagulation owing to concomitant diseases. Interruption of oral anticoagulation during TAVI may decrease the risk of bleeding, whereas continuation may decrease the risk of thromboembolism. Methods: We conducted an internat...

The optimal antithrombotic management of atrial fibrillation (AF) patients who require oral anticoagulation (OAC) undergoing percutaneous coronary intervention (PCI) remains unclear. Current guidelines recommend dual antithrombotic therapy (DAT; OAC plus P2Y12 inhibitor - preferably clopidogrel) after a short course of triple antithrombotic therapy...

Background and Aims Guidelines recommend opportunistic screening for atrial fibrillation (AF), using a 30-second single-lead electrocardiogram (ECG) recorded by a wearable device. Since many patients have paroxysmal AF, identification of patients at high risk presenting in sinus rhythm may increase the yield of subsequent long-term cardiac monitori...

A 31-year-old female patient was diagnosed with triple negative breast cancer, for which carboplatin and paclitaxel were administered through a port. At the time of port placement, neither fluoroscopic guidance, nor postoperative radiography had been possible because of pregnancy. Several months later, routine echocardiography revealed a right vent...

Background: A timely diagnosis of myocardial ischaemia is important. However, patients frequently present with rather atypical complaints. Eructonesius, or belching, is such an atypical complaint but may be considered an equivalent of angina. Case description: A 86-year-old male with known arterial hypertension was referred with longstanding eru...

Background An evaluation by the Dutch Neuro-Oncology Society (LWNO) showed that screening for psychosocial problems and the need for psychosocial care in glioma patients and their proxies is currently not optimal. Although tools to screen for psychosocial issues such as the Distress Thermometer exist, in daily practice they appear to be insufficien...

Background Direct-acting oral anticoagulant use for stroke prevention in atrial fibrillation is limited by bleeding concerns. Asundexian, a novel, oral small molecule activated coagulation factor XIa (FXIa) inhibitor, might reduce thrombosis with minimal effect on haemostasis. We aimed to determine the optimal dose of asundexian and to compare the...

Importance Inflammation promotes cardiovascular disease and anti-inflammatory treatment reduces cardiovascular events in patients with chronic coronary syndrome. Chronic kidney disease (CKD) is a risk factor for cardiovascular disease. It is unclear how inflammation mediated by interleukin 6 (IL-6) in patients with CKD is linked to cardiovascular d...

Background Guidelines recommend nonstatin lipid-lowering agents in patients at very high risk for major adverse cardiovascular events (MACE) if low-density lipoprotein cholesterol (LDL-C) remains ≥70 mg/dL on maximum tolerated statin treatment. It is uncertain if this approach benefits patients with LDL-C near 70 mg/dL. Lipoprotein(a) levels may in...

Objective To rapidly exclude severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection using artificial intelligence applied to the electrocardiogram (ECG). Methods A global, volunteer consortium from 4 continents identified patients with ECGs obtained around the time of polymerase chain reaction–confirmed COVID-19 diagnosis and age-...

Introduction Between 10-15% of patients undergoing percutaneous coronary intervention (PCI) have a history of atrial fibrillation (AF), and require both oral anticoagulant (OAC) as well as antiplatelet therapy following PCI. However this combination puts the patient at a high risk of serious or fatal bleeding complications. Using big data from elec...

Recent MitraClip heart failure (HF) trials suggest that baseline left ventricular (LV) remodeling may be critical for patient selection. We therefore investigated whether baseline LV remodeling affects safety, efficacy and clinical outcomes in HF patients with symptomatic secondary mitral regurgitation (MR) undergoing percutaneous mitral valve repa...

Background: After acute coronary syndrome, diabetes conveys an excess risk of ischaemic cardiovascular events. A reduction in mean LDL cholesterol to 1·4-1·8 mmol/L with ezetimibe or statins reduces cardiovascular events in patients with an acute coronary syndrome and diabetes. However, the efficacy and safety of further reduction in LDL cholester...

Background: Septal reduction remains an important target of current therapeutic modalities in hypertrophic obstructive cardiomyopathy (HOCM). Surgical septal myectomy has long been considered the gold standard in pharmacotherapy-refractory severely symptomatic patients with marked left ventricular outflow tract (LVOT) obstruction. In recent years,...

The radiation exposure in the cath lab of patients, cardiologists, and nurses was measured during three consecutive periods of 8 weeks. The first 8 weeks the baseline radiation exposure was obtained. In the second period standard incidences for coronarography and frame rate were changed, without compromising the image quality of the examination. In...

We evaluated whether rivaroxaban alone or in combination with aspirin would be more effective than aspirin alone for secondary cardiovascular prevention. METHODS In this double-blind trial, we randomly assigned 27,395 participants with stable atherosclerotic vascular disease to receive rivaroxaban (2.5 mg twice daily) plus aspirin (100 mg once dai...

Cardiac & Cardiovascular Systems

Background: Patients with peripheral artery disease have an increased risk of cardiovascular morbidity and mortality. Antiplatelet agents are widely used to reduce these complications. Methods: This was a multicentre, double-blind, randomised placebo-controlled trial for which patients were recruited at 602 hospitals, clinics, or community pract...

Background: Coronary artery disease is a major cause of morbidity and mortality worldwide, and is a consequence of acute thrombotic events involving activation of platelets and coagulation proteins. Factor Xa inhibitors and aspirin each reduce thrombotic events but have not yet been tested in combination or against each other in patients with stab...

Left ventricular non-compaction (LVNC) is a rare disease that can occur isolated or in association with other disorders, including congenital heart disease and musculoskeletal disorders. It is characterized by a two-layered myocardium with excessive trabeculation of the left ventricle. Diagnosis is challenging as left ventricular trabeculations can...

Left ventricular non-compaction (LVNC) is a rare disease that can occur isolated or in association with other disorders, including congenital heart disease and musculoskeletal disorders. It is characterized by a two-layered myocardium with excessive trabeculation of the left ventricle. Diagnosis is challenging as left ventricular trabeculations can...

Syncope, non-specific ST-segment alterations and elevated troponin (cTn) are suspicious of an acute coronary syndrome (ACS). While an ACS is excluded when the coronary angiogram returns normal, the raised cTn should prompt a search for other potentially lethal diseases, such as pulmonary embolism, myocarditis or malignant ventricular arrhythmias. H...

Syncope, non-specifi c ST-segment alterations and elevated troponin (cTn) are suspicious of an acute coronary syndrome (ACS). While an ACS is excluded when the coronary angiogram returns normal, the raised cTn should prompt a search for other potentially lethal diseases, such as pulmonary embolism, myocarditis or malignant ventricular arrhythmias....

An 83-year-old woman presented at the emergency department with progressive dyspnea at exertion during the last ten days. Clinical examination revealed an increased jugular venous pressure of 10 cm of water and peripheral edema. Biochemistry indicated a slightly elevated serum level of troponins. Based on the electrocardiography demonstrating a pse...

We present a case of severe haemolysis and acute renal failure 5 weeks following mitral valve repair of mitral valve prolapse. Intravascular haemolysis in this patient was caused by fragmentation of a mitral regurgitant jet due to residual prolapse and partial dehiscence of the mitral valve repair ring. Urgent redo mitral valve repair was successfu...

We present a case of severe haemolysis and acute renal failure 5 weeks following mitral valve repair of mitral valve prolapse. Intravascular haemolysis in this patient was caused by fragmentation of a mitral regurgitant jet due to residual prolapse and partial dehiscence of the mitral valve repair ring. Urgent redo mitral valve repair was successfu...

A 42-year old Caucasian male was found with first-degree atrioventricular block, right bundle branch block, and left anterior hemiblock on electrocardiogram ( Panel A ) and cardiomegaly on chest X-ray ( Panel B ). The left ventricle (LV) was severely dilated by echocardiography with a spherical shape (diastolic dimension 75 mm), reduced systolic fu...

A 34-year-old male presented with blurred vision and frontal headache since 2 months due to papilloedema and hypertensive retinopathy stage IV [ Panel A , fluoroangiography showing peripapillary oedema, cotton wool spots (arrowhead), flame shaped haemorrhages (arrow)]. His blood pressure was 210/120 mmHg. He took no oral medication, but used xylome...

Terfenadine's proarrhythmia prompted market withdrawal; therapeutic antihistaminic concentration is less than 1 nM, whereas IC50 of IKr and INa exceed 200 nM. Rabbit hearts were perfused with terfenadine (1-10,000 nM; 10-450 minutes). A dosage of 1 nM tended to shorten action potential duration (APD60) (-30 ± 30.5 ms; n = 6); 10 nM (450 minutes) si...

Carcinoid heart disease (CHD) is a rare form of valvular heart disease characterized by right-sided heart valve dysfunction. Carcinoid heart disease occurs most frequently when carcinoid tumour cells metastasize from a primary site in the gut to the liver, so that vasoactive substances produced by the tumour are able to reach the systemic circulati...

Carcinoid heart disease (CHD) is a rare form of valvular heart disease characterized by right-sided heart valve dysfunction. Carcinoid heart disease occurs most frequently when carcinoid tumour cells metastasize from a primary site in the gut to the liver, so that vasoactive substances produced by the tumour are able to reach the systemic circulati...

We report an unusual case of a 47-year-old Caucasian woman who presented with severe dyspnoea as a manifestation of restrictive cardiomyopathy, found to be due to myocardial deposition of kappa light chains. Non-routine specific immunofluorescence stainings of endomyocardial biopsy specimens were key for the diagnosis of myocardial light chain depo...

Calciphylaxis is a rare complication that occurs in 1% of patients with end-stage renal disease (ESRD) each year. Extensive microvascular calcification and occlusion/thrombosis lead to violaceous skin lesions, which progress to nonhealing ulcers with secondary infection, often leading to sepsis and death. The lower extremities are predominantly inv...

Several epidemiologic and clinical studies show that following myocardial infarction, dietary supplements of omega-3 polyunsaturated fatty acids (omega3FA) reduce sudden death. Animal data show that omega3FA have antiarrhythmic properties, but their mechanisms of action require further elucidation. The effects of omega3FA supplementation were studi...

Several epidemiologic and clinical studies show that following myocardial infarction, dietary supplements of omega-3 polyunsaturated fatty acids (omega3FA) reduce sudden death. Animal data show that omega3FA have antiarrhythmic properties, but their mechanisms of action require further elucidation. The effects of omega3FA supplementation were studi...

Coronary embolism is an uncommon cause of myocardial infarction which should be considered especially in patients with associated conditions like atrial fibrillation, intracardiac prosthesis or infective endocarditis. We present the case of a 64-year-old man with lone paroxysmal AF who sustained an acute anterior wall infarction due to an embolism...

We report a case of a 24-year-old Caucasian woman presenting with fatigue, weight loss, a cardiac murmur, anaemia and biochemical markers of inflammation due to Takayasu's arteritis (TA), a vasculitis of the aorta and large vessels that typically affects young women. The rarity of the disease, the great variability in presentation together with the...

This case illustrates the Eustachian valve as an ambiguous entity. By tethering a thrombus the valve prevented a major pulmonary embolism. However, in combination with a patent foramen ovale, it directs the thrombus into the left atrium, creating a threat for systemic embolisms.

We present the case of a 39-year-old man who was admitted to our emergency department because of acute onset of chest pain, dyspnea and fever (38,1°C). On clinical examination, the blood pressure was 170/50 mmHg at a heart rate of 136 beats per minute. A loud systolic-diastolic murmur was heard over the entire precordium with inspiratory crackles a...

The purpose of this study was to investigate the effects of bosentan (125 or 250 mg twice daily) on echocardiographic and Doppler variables in 85 patients with World Health Organization class III or IV pulmonary arterial hypertension (PAH). Bosentan, an orally active dual endothelin-receptor antagonist, improves symptoms, exercise capacity, and hem...

To evaluate whether prolongation of the plateau of the action potential duration, in the absence of instability and triangulation, can reverse the proarrhythmia elicited by a class III antiarrhythmic agent. The effects of almokalant, erythromycin and their combination, on cardiac electrophysiological parameters (action potential duration (APD), ins...

The objective of this study was to determine the effect of oral losartan on the degree of mitral regurgitation (MR). The regurgitant volume and effective regurgitant orifice were quantified using 3 methods (flow convergence, quantitative Doppler, and quantitative 2-dimensional echocardiography) in 32 patients (26 men, mean age 67 +/- 14 years) with...

The sequelae of severe brain injury include myocardial dysfunction. We sought to describe the prevalence and characteristics of myocardial dysfunction seen in the context of brain-injury-related brain death and to compare these abnormalities with myocardial pathologic changes. We examined the clinical course, electrocardiograms, head computed tomog...

To evaluate the role of intraoperative transesophageal echocardiography (IOTEE) during surgical removal of cardiac masses, we studied 75 consecutive patients (34 men, aged 56 +/- 16 years, range 17 to 82 years) who underwent surgery primarily for cardiac mass removal with the adjunct of IOTEE for the years 1993 through 1998. The IOTEE provided new...

The outcome of aortic regurgitation conservatively followed in clinical practice is poorly defined. Long-term outcome of 246 patients with severe or moderately severe aortic regurgitation diagnosed by color Doppler echocardiography was analyzed. With conservative management, mortality rate was higher than expected (at 10 years, 34+/-5%, P<0. 001) a...

Pulmonary venous flow (PVF) reversal is observed in mitral regurgitation (MR) and can be detected by Doppler echocardiography. However, the determinants of PVF alterations in MR have not been analyzed with simultaneous quantitative methods, and the diagnostic accuracy of flow reversal is uncertain. Prospectively, in 128 patients with isolated MR of...

This study sought to investigate, in patients with idiopathic-dilated cardiomyopathy, the clinical and prognostic value of a Doppler-derived index of myocardial function that combines systolic and diastolic time intervals of the left heart cycle. The Doppler index was measured in 75 patients (aged 61 +/- 13 years; 45 men and 30 women) in sinus rhyt...

Primary pulmonary hypertension is characterized by elevated pulmonary arterial pressure and vascular resistance, frequently producing right heart failure and death. Therefore, the Doppler right ventricular (RV) index, which is a measure of global RV function, could be a useful predictor of outcome in primary pulmonary hypertension. The Doppler RV i...

The proximal isovelocity surface area (PISA) method is accurate for quantitating mitral regurgitation but requires recording both mitral maximal and integrated jet velocities using the same continuous-wave Doppler jet signal. In 272 consecutive patients with isolated mitral regurgitation, the mean ratio of maximal to integral of velocity had a narr...

Quantitative Doppler echocardiography and proximal flow convergence methods are validated techniques for quantifying mitral regurgitation. However, the clinical interpretation of the values calculated is hindered by the absence of calibration of ranges of severity in large numbers of patients. In 180 consecutive patients (men, 62%; mean age+/-SD, 6...

Objectives: We sought to analyze the value of echocardiographic left ventricular (LV) diameters in assessing LV remodeling. Background: LV diameters are easily measured and commonly used as a substitute for volumetric analysis to evaluate LV remodeling caused by ventricular overload or dysfunction. However, the impact of these measurements on ou...

The incidence and impact of congestive heart failure and coronary artery disease on late survival after surgical correction of mitral regurgitation are poorly defined. In addition to the uncertainty about the frequency of this complication, the mechanisms of heart failure have not been fully analyzed. To determine survival and the incidence and mec...

Echocardiographic assessment of right ventricular function remains difficult and challenging. However, there is considerable clinical need for a simple, reproducible, and reliable parameter of right ventricular function in patients with right-sided heart disease. The purpose of this study was to assess the clinical value of a Doppler-derived index,...

This study was designed to determine the clinical value of a Doppler-derived index of combined systolic and diastolic myocardial performance in the assessment of cardiac amyloidosis. Cardiac amyloidosis is an infiltrative disease with diastolic and systolic dysfunction. Therefore, the index of myocardial performance combining systolic and diastolic...

A casual diagnosis cannot be established in 10% to 25% of the patients who are studied for fever of unknown origin (FUO). The long-term clinical outcome of these patients cannot be inferred from the literature. This study describes the results of a 5-year follow-up of 61 patients studied for FUO and discharged from the hospital with no causal diagn...