Publications by authors named "Markus Roos"

Polymer micelles are an attractive means to solubilize water insoluble compounds such as drugs. Drug loading, formulations stability and control over drug release are crucial factors for drug-loaded polymer micelles. The interactions between the polymeric host and the guest molecules are considered critical to control these factors but typically barely understood.

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Aim: To test of the implantable-cardioverter-defibrillator is done at the time of implantation. We investigate if any testing should be performed.

Methods: All consecutive patients between January 2006 and December 2008 undergoing implantable cardioverter-defibrillator (ICD) implantation/replacement (a total of 634 patients) were included in the retrospective study.

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Aims: Oesophageal probes to monitor luminal oesophageal temperature (LET) during atrial fibrillation (AF) catheter ablation have been proposed, but their effects remain unclear. Aim of this study is to evaluate the effects of an oesophageal temperature probe with insulated thermocouples.

Methods And Results: Patients with symptomatic, drug-refractory paroxysmal or persistent AF who underwent left atrial radiofrequency (RF) catheter ablation were prospectively enrolled.

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Aims: Aim of this study was to evaluate the impact of a recently introduced contact force ablation catheter with modified irrigation technology compared with a conventionally irrigated ablation catheter on the incidence of endoscopically detected oesophageal lesions (EDEL).

Methods And Results: Patients with symptomatic, drug-refractory paroxysmal or persistent atrial fibrillation (AF) who underwent left atrial radiofrequency (RF) catheter ablation were prospectively enrolled. Patients were ablated using a single-tip RF contact force ablation catheter with conventional irrigation (Group 1; n = 50) or with a recently introduced intensified 'surround flow' irrigation technology (Group 2; n = 50).

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Background: Silent cerebral events (SCEs) have been observed on diffusion-weighted cerebral magnetic resonance imaging (MRI) in a substantial number of asymptomatic patients after atrial fibrillation (AF) ablation procedures. The purpose of this study was to investigate if periprocedural oral anticoagulation (OAC) management affects the incidence of new-onset SCE after radiofrequency catheter ablation (RFCA) of AF.

Methods And Results: One hundred ninety-two consecutive patients (64 ± 10.

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Infant multiple breath washout (MBW) testing serves as a primary outcome in clinical studies. However, it is still unknown whether current software algorithms allow between-centre comparisons. In this study of healthy infants, we quantified MBW measurement errors and tried to improve data quality by simply changing software settings.

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Introduction: Focal impulses (FI) and rotors are sources associated with the initiation and maintenance of atrial fibrillation (AF). Their ablation results in a lower recurrence rate. The aim of this study was to characterize for the first time the spatial relationship between such sources and atrial low voltage zones (LVZ) representing fibrosis.

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Background: Single-shot ablation devices for pulmonary vein isolation (PVI) in patients with symptomatic atrial fibrillation (AF) have been increasingly used in clinical practice.

Objective: A novel mapping-system integrated irrigated multipolar circular ablation catheter (nMARQ) has been introduced for PVI but data on larger patient cohorts on acute safety and efficacy are lacking.

Methods: A total of 145 consecutive patients undergoing AF ablation treated with the nMARQ underwent endoscopic evaluation of esophageal thermal damage (EDEL) and brain MRI for detection of silent cerebral events (SCE).

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Background: Silent cerebral events (SCE) have been identified on cerebral diffusion-weighted cerebral magnetic resonance imaging (DE-MRI) after catheter ablation (CA) of atrial fibrillation (AF). The purpose of this study was to investigate the impact of atrial remodeling on the incidence of SCE after AF CA.

Methods: Forty patients (67.

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Background: Endoscopically detected esophageal lesions (EDELs) have been identified in apparently asymptomatic patients after catheter ablation of atrial fibrillation (AF). The use of esophageal probes to monitor luminal esophageal temperature (LET) during catheter ablation to protect esophageal damage is currently controversial.

Objective: The purpose of this study was to investigate the impact of the use of esophageal temperature probes during AF catheter ablation on the incidence of EDELs.

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Brain magnetic resonance imaging (MRI) has identified a high incidence of cerebral ischemia in asymptomatic patients after atrial fibrillation (AF) ablation (silent). Detection of cerebral ischemic events on MRI is based on acute hyperintense lesions on diffusion-weighted imaging. In the literature, the incidence is related to specifications of MRI and depends on the definition applied.

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Purpose: Cryoballoon isolation of the pulmonary veins (PVI) is an effective and safe method in the treatment of patients with paroxysmal atrial fibrillation (PAF). The circular mapping catheter Achieve® (Medtronic Inc., Minneapolis, USA) can be introduced into the pulmonary vein (PV) through the inner lumen of the balloon catheter, allowing online mapping of the PV electrograms during ablation.

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Introduction: Recurrences after pulmonary vein isolation (PVI) in patients (pts) with paroxysmal atrial fibrillation (AF) are mostly due to PV reconnection. The effect of adenosine, orciprenalin and their combination on left atrial PV conduction after PVI with a phased radiofrequency (RF) circular multielectrode ablation catheter (Pulmonary Vein Ablation Catheter, PVAC) was prospectively evaluated during a prolonged waiting time. In addition, it was assessed whether pharmacological reconnection characterizes veins requiring use of an irrigated catheter.

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Multiple-breath washout (MBW)-derived lung clearance index (LCI) is a sensitive measure of ventilation inhomogeneity in patients with cystic fibrosis (CF), but LCI measurement is time consuming. We systematically assessed ways to shorten LCI measurements. In 68 school-aged children (44 with mild CF lung disease) three standard nitrogen (N2) MBWs were applied.

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Introduction: The Brugada syndrome (BrS) can first present with syncope. Class-I antiarrhythmic drug (AAD) test is used to unmask the diagnostic coved-type ECG pattern in case it is not spontaneously present. The aim of the study was to analyze patients with BrS presenting with syncope as first manifestation and compare patients with syncope and a spontaneous coved-type ECG to patients with syncope in whom a class-I AAD test unmasked the disease.

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Background: Guidelines have become very important in assisting with decision making in clinical practice. However, few studies have analyzed the level of evidence (LOE) underlying guidelines critically. This study aims to assess the accuracy of the referenced literature that has led to recommendations with a level of evidence A (LOE-A) rating.

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The authors investigated acoustic cardiography, the digital analysis of electrocardiogram (ECG) and heart sounds, to detect phrenic nerve stimulation (PNS) and assess its hemodynamic significance. They studied 42 patients and induced 46 instances of PNS induced through cardiac pacing at various locations in the heart. These 46 instances of PNS were either independently documented using fluoroscopy or were symptomatic.

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Aims: Although it has been shown that a transseptal (TS) puncture in the electrophysiology laboratory is associated with a high success and a low complication rate, this procedure remains challenging particularly in difficult septum anatomies (aneurismal septum and thick septum) and during repeat TS catheterization. Radiofrequency (RF) electrocautery current delivery through the TS needle has been shown to facilitate the TS puncture. The aim of this study was to verify prospectively the feasibility, safety, and outcome of RF energy delivery associated with the standard TS technique in patients undergoing a challenging TS puncture.

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We present the case of a 49-year-old woman with atrioventricular nodal re-entrant tachycardia and a severe pectus excavatum. The patient underwent an electrophysiological study and fast pathway ablation. Fast pathway ablation was not done on purpose but accidentally, likely due to the abnormal position of the heart in the chest cavity in this patient suffering from severe pectus excavatum.

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In this case report we describe the important role of real-time three-dimensional transesophageal echocardiography guidance in performing double transseptal puncture for atrial fibrillation ablation in a patient who underwent a previous Tirone David intervention.

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Nowadays, trans-septal (TS) puncture is a relatively safe and straightforward procedure in experienced hands. However, in the presence of a thick, aneurysmatic or extremely elastic fossa ovalis crossing the septum might be challenging. We here describe the use of a novel guidewire that permits easy and safe 'over the wire' TS access during atrial fibrillation ablation.

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Background: Abnormally long and short QT intervals are recognized to be associated with an increased risk for life-threatening ventricular arrhythmias. It is therefore important to define the upper and lower border of the normal QT.

Objective: The aim of this study was to describe the normal distribution of the QT interval in a contemporary population of young conscripts and to define long and short limits of the QT interval.

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Atrial fibrillation (AF) is a frequent chronic dysrythmia with an incidence that increases with age (>40). Because of its medical and socio-economic impacts it is expected to become an increasing burden on most health care systems. AF is a multi-factorial disease for which the identification of subtypes is warranted.

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Article Synopsis
  • - A 43-year-old male was diagnosed with adult-onset spinal muscular atrophy (SMA) after he presented with atrioventricular (AV) block, leading to the implantation of a dual-chamber pacemaker (DDD-PM).
  • - Four years later, the pacemaker data revealed frequent episodes of nonsustained ventricular tachycardia (NSVT), which worsened over time and prompted further investigation.
  • - An electrophysiological study confirmed prolongation of the His-ventricular (HV) interval and produced sustained ventricular tachycardia, resulting in the successful upgrade of his device to a dual-chamber cardioverter defibrillator, marking the first report of such serious arrhythmias in
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Aims: Pharmacological conditioning of the phrenic nerve can positively influence systolic performance, and diaphragm activation improves ventilatory function. Here we investigate whether pacing-induced diaphragmatic stimulation (PIDS) may improve left ventricular (LV) systolic function.

Methods And Results: We studied a total of 35 patients (4 females, mean age 67 +/- 9 years, ejection fraction 61 +/- 14%) within 7 days following open heart surgery.

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