Publications by authors named "Alexander Bitzen"

Introduction: Ablation of pulmonary veins (PV) is an established therapeutic option for patients with symptomatic drug-refractory paroxysmal atrial fibrillation (AF). Radiofrequency (RF) is currently the most widespread energy source for PV ablation. Cryothermal energy applied with a cryoballoon technique as an alternative has recently evolved.

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Aims: We compared a newly developed irrigated gold tip electrode ablation catheter and a gold tip 4 and 8 mm catheter with the corresponding platinum-iridium (Pt) tip catheters in an in vitro setting.

Methods And Results: In a flow chamber simulating physiological flow conditions, radiofrequency catheter ablation was performed on tissue samples of porcine endomyocardium and liver. Lesion depth, energy and temperature delivery, and popping frequency were determined.

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Background: Patients with atrial fibrillation (AF) often exhibit abnormalities of P wave morphology during sinus rhythm. We examined a novel method for automatic P wave analysis in the 24-hour-Holter-ECG of 60 patients with paroxysmal or persistent AF and 12 healthy subjects.

Methods: Recorded ECG signals were transferred to the analysis program where 5-10 P and R waves were manually marked.

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Background: The aim of this study was to assess the efficacy of high-frequency (HF) pacing from the right atrial appendage (RAA) or coronary sinus ostium (CS-Os) for the termination of acute atrial fibrillation (AF) and atypical atrial flutter (AAFL) during an electrophysiological (EP) study.

Methods: 128 episodes of acute fast atrial arrhythmias (FAAs; 93 AF and 35 AAFL) were analyzed in 110 patients. Patients were initially observed for 60s leading to spontaneous termination of 28 FAAs.

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Aims: Amiodarone is one of the most efficient and safe antiarrhythmic drugs in the treatment of atrial fibrillation (AF). Although pro-arrhythmic effects of amiodarone therapy are rare, the aim of the present study was to identify clinical constellations which may lead to amiodarone-associated pro-arrhythmia.

Methods And Results: Sixty-three consecutive patients (pts) (49 males; 64+/-10.

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Amiodarone is one of the most efficient and safe antiarrhythmic drugs in the treatment of atrial fibrillation (AF). Yet, though rare, proarrhythmic effects remain a clinical problem. We present three cases of amiodarone-associated "Torsade de pointes" tachycardia (Tdp) in patients treated concomitantly with heart rate controlling medication for AF.

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Introduction: Cerebral embolism and stroke are feared complications of left atrial catheter ablation such as pulmonary vein (PV) ablation. In order to assess the thrombogenicity of left atrial catheter ablation, knowledge of both clinically evident as well as silent cerebral embolism is important. The aim of the current study was to examine the use of diffusion-weighted magnetic resonance imaging (DW-MRI) for detection of cerebral embolism, apparent as well as silent, caused by PV catheter ablation.

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Several prospective randomized clinical trials have reported that atrial-based "physiological" pacing is associated with a lower incidence of paroxysmal and permanent atrial fibrillation than single-chamber ventricular pacing in patients with conventional pacemaker indication. Whether atrial pacing itself is antiarrhythmic remains still uncertain. By contrast, right ventricular pacing is considered to beget atrial fibrillation, even in preserved AV synchrony during dual-chamber pacing.

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Gold-tip electrodes. Radiofrequency (RF) catheter ablation is widely used to induce focal myocardial necrosis using the effect of resistive heating through high-frequency current delivery. It is current standard to limit the target tissue-electrode interface temperature to a maximum of 60-70 degrees C to avoid char formation.

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Aims: The number of implantable cardioverter defibrillator (ICD) implantations, as well as follow-up procedures such as generator exchanges, lead revisions and lead system upgrades, is ever-increasing. Lead revisions and implantation of additional leads require venous access at the site of the previous ICD implantation. The aim of our study was therefore to evaluate the incidence of venous obstruction after chronic transvenous ICD system implantation.

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Background: Electrical isolation of pulmonary veins (PV's) is crucial to achieve success in catheter ablation for trigger elimination in focal atrial fibrillation (AF). To guide ostial PV radiofrequency (RF) delivery, it is necessary to identify the electrical breakthrough (EBT) between PV and left atrium. For this purpose, coronary sinus (CS) fixed rate pacing is commonly used.

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