Active clinical trials for "Atrial Fibrillation"

Ablation for paroxysmal atrial fibrillation (PAF) by means of pulmonary vein isolation (PVI) is the principal method for the treatment of PAF. Usually, PVI is confirmed by recording PV potentials (PVP) from the circular catheter placed at the ostium of PV. However, newer and faster methods became avialable. The only currently available technique which can visualize LA anatomy on-line, is intracardiac echocardiography (ICE). It seems that ICE could replace all other techniques used for LA imaging. Also, there may be no need for introducing diagnostic catheters and only ablation catheter and single transseptal puncture will do. Hypothesis. Simplified ICE-based ablation is faster and with shorter fluoroscopy time than standard ablation without compromising safety and efficacy and with no significant increase in costs. Aim. To compare procedural data, costs, safety and efficacy of simplified ICE-based ablation versus standard RF ablation for AF. Methods. This is prospective, controlled trial. Three centers will be included: center 1 where simplified ICE-based procedure is performed and centers 2 and 3 where standard approach is used. Patients with PAF will be allocated to two approaches: (1) standard (n=45) arm undergoing multi-electrode RF ablation in centers 2 and 3 and (2) the simple-ICE group (n=45) undergoing RF ablation in center 1 using ablation catheter and ICE catheter only. Ablation procedure will be performed using electro-anatomical system according to the CLOSE protocol. In the simple-ICE group PVI is confirmed by lack of LA capture during pacing from or up to 5 mm inside the ablation line. In the standard group both pacing from ablation line and signals from the circular diagnostic electrode will be used to confirm PVI. A one year follow-up is planned including three visits in cardiology clinics with 4-7 day Holter ECG 3, 6 and 12 months after the procedure. Assessed outcomes include duration of procedure, duration and dose of radiation, one-year procedural efficacy, peri- and post-procedural complications and cost-efficacy

This study is a prospective, randomized controlled study to evaluate intraprocedural efficacy of anterior aspects of pulmonary veins insolation between very High Power Short Duration (vHPSD) and High Power Short Duration (HPSD) in patient with paroxysmal or persistent Atrial Fibrillation.

Atrial fibrillation (AF) is the most common arrhythmia with an expected rise in prevalence over the next decade. Catheter ablation is a safe treatment option in eliminating AF however, success rates still remains variable. Existing strategies do not take into account the differences in AF perpetuation mechanisms beyond the pulmonary veins (PVs) due to the underlying substrate. Here, I will investigate the differences in persistent AF mechanisms due to the underlying substrate and utilise these findings to generate AF mechanism specific ablation strategies. I have defined a new metric, rate-dependent conduction velocity (RDCV) slowing that has shown to correlate with sites of re-entry activity in AF. In this study, techniques and methods will be developed to measure RDCV slowing sites. The impact autonomic modulation has on AF mechanisms and CV dynamics will also be assessed. The hypothesis is that a combination of structural, electrical and autonomic remodelling play an important mechanistic role in persistent AF and ablation strategies adapted to target these will result in greater procedural success rate. The study findings have the potential to improve the success rate of catheter ablation in persistent AF thereby improve patient wellbeing and reduce the cost burden of AF treatment.

This study aims at assessing whether electric cardioversion can act as a discriminant factor between patients requiring Pulmonary Vein Isolation (PVI) procedure alone or PVI procedure combined with substrate modulation. All included patients will undergo an electric cardioversion, then: Patients with electric cardioversion success will be treated as per Standard of Care and according to ESC recommendations (2020). A prospective registry will be implemented for these patients. Patients with electric cardioversion failure will be randomized in the study between 2 ablative procedures: PVI procedure alone PVI procedure combined with substrate modulation

The present study aims to investigate whether care improvement in patients after catheter ablation/cardioversion compared with standard care can be realized by using a digital eHealth platform with connected mobile sensors through early detection of atrial fibrillation recurrence and patient empowerment.

Background: A Danish study raised the question of the usefulness of escalating energy protocols compared to fixed high-energy protocols. Maximal energies are usually the final choice of the physicians. Some authors showed that decreasing impedance by manual pressure application (MPA) had a positive impact on cardioversion outcome. This is likely due to the impedance decrease linked to MPA. Objective: This new clinical cardioversion study of atrial fibrillation (AF) patients aims to compare the efficacy and safety of a new high energy escalation strategy. The protocol combines high energy shocks at first shock, jumping to maximal defibrillator energy at second shock and finally complemented by MPA at third shock, if success is not reached using electric shocks only. Experimental design: Patients will be recruited at the Intensive Cardiology Care Unit, Cardiology Clinic, National Cardiology Hospital (NCH), Sofia, Bulgaria. All eligible patients will sign a written informed consent prior to the cardioversion and will receive the standard hospital procedures during cardioversion. AF patients will be alternatively randomized to cardioversion using one of the two defibrillators, following the strategy below: DEFIGARD HD-7 arm: 3 consecutive shocks with escalating selected energy: 150J, 200J, 200J. The third shock is combined with MPA LIFEPAK15 arm: 3 consecutive shocks with escalating selected energy: 150J, 360J, 360J. The third shock is combined with MPA The statistical power analysis will consider a superiority comparison between the cumulative energy actually delivered by both defibrillators. The secondary cardioversion efficacy outcome measures are: the cumulative success rate (measured at 1 minute post-shock), number of delivered shocks. Delivered energy will be measured during each shock with a dedicated pulse recording device (approved by the NCH Ethical Committee). Heart rhythm will be measured in continuously recorded peripheral ECG. The secondary cardioversion safety outcome measures are: markers for myocardial necrosis (high sensitive troponin I, CK-MB) evaluated on blood samples taken before and 8-12 hours after cardioversion; ST-segment changes (post-shock - pre-shock) measured in lead II; Complications after cardioversion measured during 2 hours follow-up period in the ICCU - the presence of apnea, arrhythmias, bradycardia and the need for respective therapy at the discretion of attending physician.

The purpose of this study is to demonstrate the safety and effectiveness of the Cardioblate iRF and CryoFlex hand held devices for the treatment of non-paroxysmal AF.

The investigator propose to test the efficacy of adjunctive ET-GP ablation in patients undergoing redo PVI for paroxysmal AF.

This prospective randomized study will assess the safety and efficacy of FIRM-guided ablation (FIRM+PVI) compared to pulmonary vein isolation (PVI) without FIRM, for the treatment of symptomatic atrial fibrillation.

In this pilot and feasibility study, the investigators will enroll patients with frequent symptomatic episodes of atrial fibrillation (AF) in a cross-over study testing two different classes of anti arrhythmic drugs (AADs). This pilot and feasibility study will provide preliminary data for a larger study in which the investigators will test the hypothesis that a common AF genetic risk allele modulates response to different AADs.