View clinical trials related to Tachycardia.
Filter by:To generate a list of potential genetic markers that correlate with an increased risk of life-threatening arrhythmias. To evaluate ECG-based risk markers such as heart rate variability and T-wave Alternans for their association with arrhythmic events.
In case of sinus node dysfunction, it is often necessary to choose the safer option provided by a DDD pacemaker even though the most appropriate mode of pacing is AAI mode. In addition to saving energy, the latter mode allows spontaneous ventricular activation, the haemodynamic consequences of which are, in most cases, better than those obtained with dual chamber pacing. Recent studies as the MOST study suggest also that ventricular desynchronization imposed by right ventricular apical pacing even when AV synchrony is preserved increases the risk of atrial fibrillation in patients with SND. Similar results were already given by anterior studies (PIPAF) which, taking into account the percentage of ventricular pacing, suggested that AF prevention algorithm in combination with a preserved native conduction are efficient in reducing AF burden. However, current practice is to implant a dual chamber pacemaker to prevent the risk of atrioventricular block (AVB) even if DDDR pacing with a fixed long AV delay was found inefficient in reducing ventricular pacing and was associated with a high risk of arrhythmias. The Symphony 2550 cardiac pacemaker offers pacing modes that automatically switch from AAI(R) mode to DDD(R) or DDI(R) in event of severe atrioventricular conduction disorder, irrespective of whether or not these are accompanied by an atrial arrhythmia, returning spontaneously to AAI(R) mode as soon as the spontaneous AV conduction has resumed. These 2 particular modes are called the AAI SafeR and DDD/AMC (R) mode. The main differences between both modes are that (i) AAI SafeR does not trigger any AV Delay after a sensed or paced atrial event which allows long PR intervals or even limited ventricular pauses with no switch to DDD(R), while (ii) DDD/AMC (R) is able to optimize AV Delay after switching to DDD(R) according to measured spontaneous conduction times and to provide an acceleration in case of vaso-vagal syndrome. This pacing mode has previously been assessed in clinical studies. This study intends to demonstrate that the automatic modes switching significantly reduce the percentage of ventricular pacing in patients implanted with a spontaneous AV conduction and reduce the occurrence of atrial arrhythmias, on a mid-term follow-up period, in comparison to standard DDD pacing with long AVDelay.
- Determine the accuracy of the NTX wireless monitoring system alerts - Evaluate patient compliance with wearing device - Determine false alarm rates
- Reduction in time to detection of Clinically Significant events - Reduction of time to Intervention during Clinically Significant events - Reduction in the number of admissions to Intensive Care
The purpose of this post approval study of heart block is to gather additional information regarding how often patients develop heart block (atrioventricular block) after having standard ablation procedure using cryotherapy with the Freezor™ catheter.
The MADIT-II trial has shown that patients with severely reduced left ventricular ejection fraction (LVEF) post myocardial infarction benefit from the implantable cardioverter-defibrillator (ICD). However, retrospective analyses of the MADIT-II data have revealed a significantly increased morbidity and mortality in patients with appropriate ICD therapy: Appropriate ICD therapy is associated with 3.3-fold increased all-cause mortality, and the risk of a first heart failure hospitalization is 90% higher after 1st appropriate ICD therapy. Hence, the 1st appropriate therapy might indicate the necessity and utility of further clinical diagnostics and therapy in these patients. This trial is designed to (i) improve the knowledge of the group characteristics of patients suffering from 1st appropriate ICD therapy, (ii) but moreover to take additional therapeutic steps to reduce the mortality of this patient population.
The purpose of this study is to determine/identify what mechanisms/factors are involved with regard to AV nodal reentrant tachycardia.
Many arrhythmias detected in the ventricular fibrillation (VF)-zone picture monomorphic ventricular tachycardia (VT) and, hence, could be terminated by antitachycardia pacing (ATP) treatment. Advantages of successful ATP are the painlessness termination and the shortened duration of arrhythmia. The ATP One Shot algorithm is integrated in the latest family of implantable cardioverter defibrillators (ICDs) from BIOTRONIK (Lumax). It allows a single delivery of ATP before charging capacitors to terminate lethal arrhythmia by painful shock. The present study evaluates the efficacy of the ATP One Shot algorithm for the termination of fast VT episodes. 200 patients with secondary prophylactic ICD indication will be followed for 18 months. Spontaneous episodes detected in the VF-zone of the ICD will be evaluated with regard to cycle length, episode duration and course of device therapy.
The purpose of this study is to describe the mechanism of orthostatic intolerance, relying on cardiovascular physiological studies. The syndrome is of undetermined etiology, but the syndrome causes impairment of a number of young adults, females more than males, with symptoms of tachycardia, fatigue, lightheadedness, palpitations, blurred vision, chest discomfort, difficulty concentrating, and dizziness with the upright posture. It is believed that many different pathophysiological processes can give rise to this disorder.
The COGENT-4 Field Following Study will evaluate the clinical performance of the Boston Scientific TELIGEN 100 HE Implantable Cardioverter Defibrillator (ICD), the COGNIS 100 HE Cardiac Resynchronization Therapy ICD (CRT-D) systems and the RELIANCE 4-SITE defibrillation lead (when available). An optional sub-study will also evaluate the clinical performance of the Reverse Mode Switch (RMS) feature in the TELIGEN 100 HE DR ICD.