Performance of an implantable cardioverter-defibrillator lead family.

Background: Lead failure is the major limitation in implantable cardioverter-defibrillator (ICD) therapy. Long-term follow-up data for Biotronik Linox ICD leads are limited. Therefore, we analyzed the performance of all these leads implanted at our institution.

[Reflex syncope-or more? : Ictal asystole!].

A 59-year-old male patient was admitted for possible reflex syncope following loss of consciousness during urination. During the visit, a malaise with unconsciousness occurred. Holter ECG at that time showed increasing sinus bradycardia with transition to a junctional escape rhythm (30/min); in addition, there were several sinus pauses > 2.

[Premature ventricular contractions and tachycardia in a structurally normal heart : Idiopathic PVC and VT].

Premature ventricular contractions (PVC) are a common, often incidental and mostly benign finding. Treatment is indicated in frequent and symptomatic PVC or in cases of worsening of left ventricular function. Idiopathic ventricular tachycardia (VT) is mostly found in patients with a structurally healthy heart.

Updated Survey on Interventional Electrophysiology: 5-Year Follow-Up of Infrastructure, Procedures, and Training Positions in Germany.

Objectives: This study provides an update and comparison to a 2010 nationwide survey on cardiac electrophysiology (EP), types and numbers of interventional electrophysiological procedures, and training opportunities in 2015.

Background: In 2010, German cardiology centers performing interventional EP were identified and contacted to provide a survey on cardiac EP.

Methods: German cardiology centers performing interventional EP in 2015 were identified from quality reports and contacted to repeat the 2010 questionnaire.

[AV-reentrant tachycardia and Wolff-Parkinson-White syndrome : Diagnosis and treatment].

The AV-reentrant tachycardia (AVRT) is a supraventricular tachycardia with an incidence of 1-3/1000. The pathophysiological basis is an accessory atrioventricular pathway (AP). Patients with AVRT typically present with palpitations, an on-off characteristic, anxiety, dyspnea, and polyuria.

Hyperaldosteronism induces left atrial systolic and diastolic dysfunction.

Patients with hypertension and hyperaldosteronism show an increased risk of stroke compared with patients with essential hypertension. Aim of the study was to assess the effects of aldosterone on left atrial function in rats as a potential contributor to thromboembolism. Osmotic mini-pumps delivering 1.

Low-Level But Not High-Level Baroreceptor Stimulation Inhibits Atrial Fibrillation in a Pig Model of Sleep Apnea.

Background: Obstructive sleep apnea (OSA) increases susceptibility to atrial fibrillation (AF) by a combined sympatho-vagal hyperactivation. The purpose of this study was to investigate the effect of autonomic nervous system modulation by low-level baroreceptor stimulation (LL-BRS) compared to high-level BRS (HL-BRS) on atrial arrhythmogenic changes in a pig model of OSA.

Methods And Results: Sixteen pigs received tracheotomy under general urethane/chloralose anesthesia.

[Typical atrial flutter: Diagnosis and therapy].

Typical, cavotricuspid-dependent atrial flutter is the most common atrial macroreentry tachycardia. The incidence of atrial flutter (typical and atypical forms) is age-dependent with 5/100,000 in patients less than 50 years and approximately 600/100,000 in subjects > 80 years of age. Concomitant heart failure or pulmonary disease further increases the risk of typical atrial flutter.

[AV nodal reentrant tachycardia. Diagnosis and therapy].

The AV nodal reentrant tachycardia (AVNRT) is one of the most common arrhythmias encountered in clinical practice. It is characterized by a constant heart rate and an on/off phenomenon. The clinical symptoms may include palpitations, anxiety, polyuria, and dyspnea.

Obstructive respiratory events and premature atrial contractions after cardioversion.

Recurrence of atrial fibrillation (AF) after electrical cardioversion (ECV) is increased in patients with obstructive sleep apnoea (OSA). In patients with persistent AF, with (n=40) and without (n=32) obstructive respiratory events (OREs) during sedation for ECV, we determined the occurrence of premature atrial contractions (PACs) before and after insertion of a nasopharyngeal tube. The influence of acute obstructive respiratory events on atrial electrophysiology after termination of AF was studied in pigs.

Catheter-based renal denervation reduces atrial nerve sprouting and complexity of atrial fibrillation in goats.

Background: Atrial fibrillation (AF) leads to structural and neural remodeling in the atrium, which enhances AF complexity and perpetuation. Renal denervation (RDN) can reduce renal and whole-body sympathetic activity. Aim of this study was to determine the effect of sympathetic nervous system modulation by RDN on atrial arrhythmogenesis.

Renal denervation: effects on atrial electrophysiology and arrhythmias.

Atrial fibrillation (AF) is the most common sustained arrhythmia and is associated with significant morbidity and mortality. Currently, atrial endocardial catheter ablation, mainly targeting focal discharges in the pulmonary veins, is the most widely used interventional treatment of drug-refractory AF. Despite technical improvements, results are not yet optimal.

Atrial autonomic innervation: a target for interventional antiarrhythmic therapy?

Atrial fibrillation is the most common arrhythmia and is associated with significant morbidity and mortality. The autonomic nervous system contributes to the creation of atrial fibrillation substrates. Atrial electrophysiology is influenced differently by sympathetic and parasympathetic activation.

Renal denervation suppresses ventricular arrhythmias during acute ventricular ischemia in pigs.

Background: Increased sympathetic activation during acute ventricular ischemia is involved in the occurrence of life-threatening arrhythmias.

Objective: To test the effect of sympathetic inhibition by renal denervation (RDN) on ventricular ischemia/reperfusion arrhythmias.

Methods: Anesthetized pigs, randomized to RDN or SHAM treatment, were subjected to 20 minutes of left anterior descending coronary artery (LAD) occlusion followed by reperfusion.

Potential role of renal sympathetic denervation for the treatment of cardiac arrhythmias.

The autonomic nervous system (ANS) has a pivotal role in the pathogenesis and maintenance of atrial and ventricular arrhythmias. Catheter-based renal denervation (RDN) is associated with a reduction of central sympathetic activity, muscle sympathetic nerve activity, and blood pressure in resistant hypertension. As renal afferent nerves are regulators of central sympathetic tone, RDN opens the possibility to modulate sympathetic activity, but without affecting peripheral chemoreceptors and mechanoreceptors in the heart and other organs.

A survey of German centres performing invasive electrophysiology: structure, procedures, and training positions.

Aims: To provide a nationwide survey (and reference for the future) on cardiac electrophysiologists, types and numbers of invasive electrophysiological procedures, and training opportunities in 2010.

Methods And Results: German cardiology centres performing invasive electrophysiology were identified from quality reports and contacted to fill a questionnaire. A majority of 122 centres (65%) responded.

Effects of electrical stimulation of carotid baroreflex and renal denervation on atrial electrophysiology.

Introduction: This study was designed to compare the effect of electrical baroreflex stimulation (BRS) at an intensity used in hypertensive patients and renal denervation (RDN) on atrial electrophysiology. BRS and RDN reduce blood pressure and global sympathetic drive in patients with resistant hypertension. Whereas RDN decreases sympathetic renal afferent nerve activity, leading to decreased central sympathetic drive, BRS modulates autonomic balance by activation of the baroreflex, resulting in both reduced sympathetic drive and increased vagal activation.

Calcium dysregulation in ventricular myocytes from mice expressing constitutively active Rac1.

Increased Rac1 activity and its concomitant elevation of reactive oxygen species (ROS) levels is believed to be involved in the development of cardiac diseases such as hypertrophy and arrhythmia. To study the effects of activated Rac1 on the properties of isolated ventricular myocytes we used a transgenic mouse model (RacET) expressing constitutively active Rac1. Concurrent with dilated cardiomyopathy global Ca(2+) handling as well as single cell contractility was substantially decreased.

Renal sympathetic denervation provides ventricular rate control but does not prevent atrial electrical remodeling during atrial fibrillation.

Renal denervation (RDN) reduces renal efferent and afferent sympathetic activity thereby lowering blood pressure in resistant hypertension. The effect of modulation of the autonomic nervous system by RDN on atrial electrophysiology and ventricular rate control during atrial fibrillation (AF) is unknown. Here we report a reduction of ventricular heart rate in a patient with permanent AF undergoing RDN.

Effects of renal sympathetic denervation on heart rate and atrioventricular conduction in patients with resistant hypertension.

Background: Renal sympathetic denervation (RDN) reduces sympathetic activity and blood pressure (BP) in patients with resistant hypertension. The present study aimed to investigate the effects of RDN on HR and other electrocardiographic parameters.

Methods: 136 patients aged 62.

Heart rate reduction by If-inhibition improves vascular stiffness and left ventricular systolic and diastolic function in a mouse model of heart failure with preserved ejection fraction.

Aims: In diabetes mellitus, heart failure with preserved ejection fraction (HFPEF) is a significant comorbidity. No therapy is available that improves cardiovascular outcomes. The aim of this study was to characterize myocardial function and ventricular-arterial coupling in a mouse model of diabetes and to analyse the effect of selective heart rate (HR) reduction by If-inhibition in this HFPEF-model.