Clinical Research Directory

Hybrid Ablation of Atrial Fibrillation in Heart Failure

A randomised controlled trial to assess the efficacy of staged hybrid ablation when compared with standard catheter ablation in patients with non-paroxysmal atrial fibrillation (AF) and Heart Failure

Atrioventricular Node Ablation and Conduction System Pacing in Patients With Well Controlled Permanent Atrial Fibrillation (AF), Heart Failure and Preserved Ejection Fraction: Heart Rate Regularization Versus Medical Rate Control

The goal of this clinical trial is to assess the clinical efficacy of physiological pacing combined with atrioventricular node ablation, in patients with Heart Failure with preserved Ejection Fraction (HFpEF) and well controlled permanent atrial fibrillation.The main question it aims to answer is that heart rate regularization added to physiological pacing - preventing the deleterious effect of right ventricular apical pacing - would reduce mortality and heart failure hospitalizations. Researchers will compare physiological pacing combined with atrioventricular node ablation (intervention arm) versus optimal pharmacological therapy (control arm) to see if physiological pacing combined with atrioventricular node ablation reduce time to the composite of all-cause mortality or hospitalization due to heart failure or intravenous diuretics (time frame 24 months). Participants will : * Be randomized in intervention arm or control arm. * Visit the clinic 3 months, 12 months and 24 months after the randomization for checkups and tests.

Noninvasive 3D Mapping in Persistent Atrial Fibrillation, to Describe Modifications of the Arrhythmogenic Substrate After Pulmonary Vein Isolation and Identify Potential Predicting Factors of Ablation Success

Atrial fibrillation (AF) is the most common cardiac arrhythmia in adults. It is a major cause of ischemic stroke and heart failure. Intravascular cardiac ablation of the left atrium by catheter delivery is an efficient treatment to restore sinus rhythm. AF ablation is a class IIa treatment for patients with symptomatic persistent AF refractory or intolerant to antiarrhythmic medication. There are still many debates considering the ablation strategy. The pulmonary veins remain the cornerstone of AF ablation therapy, even in persistent AF. There is a large electrical remodeling occurring in the left atrium between paroxysmal AF, early persistent AF and long-standing persistent AF. However, no multicentric and randomized study has demonstrated so far the interest of targeting other left atrial substrate, such as rotors or focal sources. Our study aims to describe with a noninvasive mapping system the arrhythmogenic substrate of persistent AF \> 6 months pre- and post-cardioversion, and after pulmonary vein isolation.

Value of Screening and Treatment of SAHS in the Management of AF Ablation Candidates

The present prospective cohort study (not randomized) analyses the value of screening and treatment of SAHS in the management of patients with AF refractory to antiarrhythmics drugs, potentially candidates for ablation. Patients at low risk of suffering from SAHS will follow conventional management of their AF, according to the usual criteria of the Arrhythmia Unit. Patients with high or intermediate risk of SAHS, will undergo respiratory polygraphy. If the result is positive, they will be treated as standard for this syndrome and their heart rate will be monitored for 3 months. After this, the patient's arrhythmic load will be reevaluated differentiating patients into two groups, those that must be ablated from those that have improved their condition and the clinical criteria is no longer ablation but follow-up.

Convergent Ablation Plus Left Atrial Appendage Isolation for the Treatment of Persistent Atrial Fibrillation

A randomised controlled clinical trial to assess efficacy of convergent ablation with the LARIAT procedure, as compared to standard endocardial catheter ablation in patients with long-standing persistent atrial fibrillation (AF).

Triple Atria Extrastimuli vs Pulmonary Vein Isolation Alone in Persistent Atrial Fibrillation

The problem addressed in this proposal is related to the success rate in treating one of the most common arrhythmias in the Western population, atrial fibrillation (AF). Specifically, the success rate is particularly low in persistent atrial fibrillation, being up to 40% lower than the success rate for paroxysmal atrial fibrillation. Atrial fibrillation is associated with increased mortality and morbidity (stroke, heart failure, dementia, etc.). The most effective treatment is electrical isolation of the pulmonary veins (PVI) by catheter ablation using radiofrequency or cryoablation of the atrial myocardial tissue. This ablation allows the elimination of the main initiators of the arrhythmia but may not address its maintainers, which play a significant role in persistent atrial fibrillation. This project proposes a new approach in studying the atrial myocardial substrate for persistent fibrillation ablation. Until now, maintainers of the arrhythmia have been sought by conducting studies during atrial fibrillation. In this project, we will use short-coupled stimulation techniques during sinus rhythm and analyze the response of the atrial myocardium, attempting to unmask areas where the impulse propagates abnormally/slowly. These areas of the atrial muscle with hidden slow conduction (HSC) could generate short circuits that maintain atrial fibrillation. It would be expected that these areas would show fragmented electrograms in response to rapid electrical stimuli not visible in basal rhythm. The study is divided into two sub-studies to be carried out over the 3-year project. 1. This study aims to test the feasibility of this new arrhythmic substrate characterization strategy, as well as observe differences between patients with paroxysmal and persistent AF and compare it with conventional fragmented electrogram analysis during AF. 2. The second sub-study will apply the knowledge acquired during the first phase regarding the characterization of electrograms-HSC, allowing for radiofrequency ablation procedures to be performed using a new substrate ablation technique consisting of the elimination of these electrograms and comparing the results with those patients who undergo conventional pulmonary vein ablation techniques. The ultimate goal, from a global point of view, is to demonstrate that it is possible to improve the results of arrhythmia treatment by identifying and eliminating these electrograms-HSC.

RESOLVE-AF: Clinical Evaluation of the Ablacath™ Mapping Catheter and Ablamap® System Utilizing Electrographic Flow (EGF) Mapping to Resolve Extra-PV Sources of Atrial Fibrillation and Guide Ablation Therapy.

Demonstrate the safety and effectiveness of the Ablacath™ Mapping Catheter and Ablamap® System in patients with all types of atrial fibrillation (AF) including paroxysmal or persistent or long-standing persistent, undergoing and De Novo or Redo procedures. Phenotype patients and demonstrate the prognostication power of Electrographic Flow (EGF®) maps among all subjects using 12-month follow-up outcomes following EGF-guided mapping and ablation.

Re-ablation of Persistent Atrial Fibrillation

Pulmonary vein re-isolation plus Vein of Marshall ethanol ablation in combination with block of mitral and tricuspid isthmuses and dome line will be compared to pulmonary vein re-isolation alone in patients undergoing re-ablation for persistent atrial fibrillation in this investigator initiated, randomized, patient-assessor blinded multicenter trial. Patients are followed with standard ECG at 3 months, with standard ECG, 5-days' ECG monitoring and quality of life assessment after 12 months, with standard ECG and quality of life assessment after 24 months, through patient files at 60 months after the ablation. Primary endpoint: Change in AFEQT score between baseline and 12 months.

Assert-IQ Implantable Cardiac Monitor (ICM) Post Market Study

This is a prospective, non-randomized, multi-center, real-world post-market study to collect and evaluate data regarding the performance of the enhanced atrial fibrillation detection algorithm of the Assert-IQTM Implantable Cardiac Monitor (ICM) device.

Electrical Cardioversion As a Predictor in Postoperative Preservation of Sinus Rhythm

The aim of this study is to evaluate benefits of electric cardioversion in the early and long-term postoperative period in patients after radiofrequency catheter isolation of pulmonary veins. Parameters of the left atrium will be evaluated by transthoracic echocardiography and electroanatomic mapping. Preservation of the sinus rhythm will be assessed by 24-hour electrocardiographic monitoring. The main question that is planned to be answered is: Does a reverse remodeling of the left atrium and/or a decrease in the progression of the fibrosis zone occur after performing electrical cardioversion (and before subsequent catheter ablation) in patients with persistent and long-standing persistent atrial fibrillation (AF)? Can performed electrical cardioversion serve as a predictor of AF freedom in this group of patients? Participants will undergo a follow-up examinations (echocardiography, ECG, 24-hour ECG monitoring) at the 3rd, 6th and 12th months after catheter ablation. Based on the results of these examinations, the recurrence rate of AF will be estimated. Two groups of patients will include both persistent and long-standing persistent AF. Experimental group will include patients who underwent electrical cardioversion before the intervention, and active comparator group will include those patients who did not undergo it. The experimental group will be subdivided into a persistent AF patients who were successfully cardioverted in sinus rhythm and persistent AF patients who failed to restore sinus rhythm during DC at the time of catheter ablation. Analysis and comparison of subgroups will be performed.

Atrial Fibrillation Ablation Versus Atrioventricular Nodal Ablation with Conduction System Pacing in Heart Failure

The goal of this clinical trial is to evaluate two treatment strategies in patients with chronic atrial fibrillation and heart failure, who are eligible for atrial fibrillation ablation. Patients will be randomized to either atrial fibrillation ablation or to implantation of a pacemaker with conduction system pacing followed by atrioventricular node ablation. The effect of treatment allocation on total mortality, cardiovascular hospitalization and heart failure hospitalization will be compared.

Cyroablation for Pulmonary Vein Isolation Alone in Patients with Early Persistent AF Assessed by Continuous Monitoring

This study aimed to evaluate the efficacy of Cryoablation in patients with early persistent atrial fibrillation as a first index procedure using continuous cardiac rhythm monitoring.

Optimal Pacing Rate for Cardiac Resynchronization Therapy

This is a prospective, randomized crossover study. The objective of the study is to determine if a pacing rate of 80 beats per minute (bpm) improves exercise tolerance during the 6-minute walk test. The investigators will randomly assign half of the participants to a starting rate of 60 bpm and then switch them to a rate of 80 bpm for 3 months, and vice versa.

Comparison of Catheter Plus Marshall Vein Ablation vs. Catheter Ablation Alone in Persistent AF With Heart Failure

This multicenter, randomized controlled trial aims to compare the clinical efficacy and safety of combining catheter ablation with Marshall vein ethanol ablation versus catheter ablation alone in patients with persistent atrial fibrillation (AF) and concomitant heart failure. Persistent AF is a common arrhythmia that significantly impacts the quality of life and survival rates, especially when coexisting with heart failure. While catheter ablation is a standard treatment for AF, its effectiveness in persistent AF, particularly in patients with heart failure, remains suboptimal. The addition of Marshall vein ethanol ablation may enhance treatment outcomes by targeting arrhythmogenic substrates. This study will enroll 120 participants across three centers to evaluate whether this combined approach can reduce AF recurrence, improve heart function, and enhance patient outcomes compared to catheter ablation alone.

Ablation of Focal Activation in Atrial Fibrillation

Recurrent focal electrical activation (or ectopy) superseding sinus activation is the only mechanism proven to drive paroxysmal atrial fibrillation (AF). However, it has not been possible to show similar focal drivers during AF, owing to the limitations of mapping in persistent AF. RETRO-Mapping has been developed as a method to generate activation maps during AF to test the hypothesis that persistent AF is also maintained by focal drivers. RETRO-Mapping is able to locate sites of focal activation that were isolated, intermittent, or recurrent during persistent AF. However, a 30-second segment of AF can have approximately 150 wavefronts in a small area of myocardium. Screening for focal activation and manually validating these prior to ablation was not feasible using current commercial systems. RETRO-Mapping can automatically detect focal activation and a recording system that enables the intracardiac signals to be directly analysed by the RETRO-Mapping software. This will allow RETRO-Mapping to build a detailed classification of focal activation types and study the impact of ablation of these sites on the AF cycle length, to address the hypothesis that persistent AF is maintained by focal drivers.

Left Roof Linear, Mitral Isthmus Linear and Left Anterior Septal Linear Ablation for Non-paroxysmal AF: PROMISED Trial.

The purpose of this prospective randomized study is to assess whether a new treatment strategy consisting of circumferential Pulmonary vein isolation (PVI), left ROof linear (RL), Mitral Isthmus linear (MIL), and left anterior SEptal linear (ASL) ablation and left atrial appendage (LAA) Device occlusion (PROMISED procedure) is superior to the PVI combined LAA closure in enhancing the long-term success rate of catheter ablation in non-paroxysmal atrial fibrillation (AF) patients.

Thoracoscopic Surgical Versus Catheter Ablation Approaches for Primary Treatment of Persistent Atrial Fibrillation

Rationale: Atrial fibrillation (AF) is a highly prevalent cardiac arrhythmia. AF is classified as paroxysmal or persistent AF, based on the duration and persistency of the arrhythmia. Despite state-of-the-art pharmacological therapies targeting the ventricular rate or aiming to restore sinus rhythm, many patients with persistent AF stay symptomatic. Catheter ablation, endocardial pulmonary vein isolation (PVI) in particular, is the most commonly applied approach to treat drug refractory persistent AF, but particularly in this patient group results are modest. Alternatively, the PVs can be approached epicardially by thoracoscopic surgery to isolate the PVs. This approach is more efficacious, at the cost of a more invasive procedure and longer hospital stay. However, no studies have been conducted comparing catheter with thoracoscopic ablation in patients with persistent AF as a primary invasive procedure after failing treatment with anti-arrhythmic medication. Objective: This current study aims to assess a patient specific therapy plan for patients with persistent AF by randomizing thoracoscopic versus catheter ablation for PVI without adjuvant substrate ablation in those patients. Study design: This is a prospective, non-blinded randomized multicenter study. Subjects will be randomized (1:1) to one of the two study-arms (thoracoscopic surgical or catheter PVI). The follow-up will last 5 years, with heart rhythm monitoring at three and six months, one year and yearly in the following years. In case AF recurs during the first year, the subject will receive the treatment of the otherother arm, or according to patient choice or clinical routine. Study population: Patients with an indication for invasive treatment of persistent AF. Intervention: Thoracoscopic surgical or catheter PVI without additional lesions.

A Prospective Study of REPeat Ablation In Patients With Recurrent PERSistent Atrial Fibrillation: Pulmonary Vein Isolation vs. Adjunct Posterior Wall Isolation (REPAIR PERS-AF Study)

This study aims to investigate the best strategy for repeat ablation of recurrent persistent atrial fibrillation (AF) after previous persistent AF ablation involving pulmonary vein isolation (PVI) along. Patients with low voltage areas on the posterer wall will be randomized to PVI alone or the posterer wall isoaltion (PWI) in addition to PVI.

First-line Cryoablation for Early Treatment of Persistent Atrial Fibrillation

The goal of this multicentre, prospective, randomized, open, blinded for evaluation of end point (PROBE) controlled parallel-group superiority trial, is to compare the efficacy of antiarrhythmic drug (AAD) therapy and cryoballoon pulmonary vein isolation (PVI) regarding freedom from atrial fibrillation (%) assessed by an implantable cardiac monitor (ICM), ECG tracing or Holter at 12 months in patients with persistent AF. The main question\[s\] it aims to answer are: * Will first-line cryoballoon ablation for PVI compared to AAD, result in 25 % higher freedom from atrial tachyarrhythmias lasting \> 6 minutes at 12 months (primary outcome) excluding three months initial blanking period, in patients with symptomatic and recurrent persistent AF? * Will first-line cryoablation for PVI, compared to AAD result in a superior improvement in health related Quality of Life (HRQoL), AF/AT burden, AF/AT progression and reversion, more reverse atrial remodeling, cognitive function, healthcare utilization with associated costs, better safety, at 12-24-36 months as compared with drug use? Participants will be randomized 1:1 to first-line PVI using the cryoballoon or to first-line antiarrhythmic drug therapy and during 3 years follow-up undergo regular; * Continuous ECG monitoring for assessment of first AF recurrence and AF burden using an implantable cardiac monitor, * Regular echocardiographic exams for reverse atrial remodelling assessment, * HRQoL questionnaires * Assessment of cognitive function * Atrial fibrillation evaluation regarding structured characterisation and AF progression/regression * Assessment of Health care use and costs * Safety