Active clinical trials for "Atrial Fibrillation"

To compare the efficiency and safety between gene-oriented group and standard care group during 90 days of initial warfarin-treatment for requiring anticoagulation patients with valve replacement or atrial fibrillation with or without valvular heart disease。

Atrial fibrillation (AF) is a very common abnormal heart rhythm, triggered by rapid electrical activity originating from the pulmonary veins (PVs) that drain blood from the lungs back to the left atrium (LA). Ablation of the junction between the PVs and the LA, electrically isolating the veins from the heart, is the key to prevent AF. When using radiofrequency energy (RF), transmural lesions are required to achieve permanent pulmonary vein isolation (PVI). New technologies are currently available to predict the ablation lesion depth and to guide the duration of each application. However, deeper lesions mean a higher risk of overheating and damage of adjacent structures such as the esophagus that lies against the back wall of the LA. In order to minimize this risk, the investigators continuously monitor the temperature inside the esophagus during the procedure through a probe placed in the esophagus and they promptly terminate energy delivery in case of any esophageal temperature rises more than 39°C. To date, it is not known if a low power for a longer time is better than a high power for a shorter time when ablating on the LA posterior wall in order to create permanent scars without heating the esophagus. Therefore, the investigators plan to compare the incidence of esophageal temperature alerts and the success of the procedure with four different energy settings during ablation on the LA posterior wall.

The RATAF II study is a randomized, prospective, parallel group study, designed to compare the effects of two different drug regimens for rate control in permanent AF (atrial fibrillation). We will investigate on the difference in effects on exercise capacity, biomarkers (NT-proBNP (N-terminal pro-brain natriuretic peptide), troponins, hs-CRP), heart rate, echocardiographic measurements and symptoms. Our main hypothesis is that six months' treatment with the calcium channel blocker diltiazem will lower NT-proBNP and increase exercise capacity (peak VO2) compared to treatment with the beta blocker metoprolol in permanent AF.

Atrial fibrillation is a common heart rhythm disturbance, causing important discomfort for patients, a high risk of stroke, frequent hospital admissions and a two-fold increase in death. The number of patients with this condition are expected to double in the next 20 years. Medications to control heart-rate are used in the majority of patients, although the choice of agent is often guided by local preference rather than evidence from controlled trials. Despite the fact that patients with atrial fibrillation have high rates of other cardiac conditions such as heart failure, clinicians have insufficient evidence to personalise the use of different therapies. This feasibility study will allow us to develop a range of methods that can characterise patients according to the pumping and relaxing function of the heart, the burden of symptoms and to identify new blood markers. In this way, the investigators hope to improve clinical practice guidelines, allowing doctors to prescribe appropriate treatments for the right patients. The research will be focused around a randomised trial of two medication strategies, providing much-needed data on the comparison of digoxin and beta-blockers (two commonly-used drugs in patients with atrial fibrillation). It will also allow us to identify the best way to record patient-reported quality of life and develop robust techniques to determine heart function using non-invasive imaging, facilitating the conduct of a large-scale clinical trial. The key objectives of the research programme are to define the optimal medications for patients with atrial fibrillation and identify the most valid, reproducible and cost-effective methods to examine patients. The ultimate aim of the project is to improve clinical outcomes in atrial fibrillation, benefiting patients, the National Health Service and the global community.

Prospective trial comparing the efficacy and safety of CryoBalloonAblation (CBA) to standardized medication for treatment of early onset persistent atrial fibrillation (AF) without structural heart disease. The value of CBA in these patients has never been studied; the endpoints for persistent patients are much easier than for paroxysmal patients. Reduction in left atrial (LA) size will be compared versus patients on drug therapy and versus failing patients.

A streamlined AF ablation procedure done without PV mapping as a daycase is more effective than anti-arrhythmic drugs at reducing all hospital episodes for recurrent atrial fibrillation.

This study aims to validate a new dosage of cryotherapy based on time to effect in pulmonary vein ablation procedures in patients with paroxysmal atrial fibrillation.

It is hypothesised that a dual therapy strategy by oral anticoagulation with the new Factor-Xa-inhibitor apixaban plus clopidogrel is superior to a triple therapy regimen with phenprocoumon plus acetylsalicylic acid (ASA) and clopidogrel with respect to avoiding bleeding events in patients with atrial fibrillation undergoing percutaneous coronary intervention in the setting of an acute coronary syndrome.

The overall goal of this project is to test the feasibility of performing real-time electrogram morphology recurrence (EMR) mapping in patients with persistent atrial fibrillation (AF) to locate areas of high electrogram morphology recurrence rate. The Investigator believe that the EMR mapping can be integrated into cardiac mapping and used to identify potential sites for ablation. Furthermore, this study could help demonstrate the efficacy of this technology's ability to terminate or slow AF. The Investigator will test this technology on ten subjects undergoing a second ablation procedure. The Investigator will map the AF utilizing the EMR to indicate locations of stable activity and ablate the area. The Investigator believes that the study could produce acute AF termination or AF cycle length slowing. In addition to testing the real-time electrogram morphology recurrence mapping, the study would also like to determine the acute effects of radiofrequency ablation of areas of high recurrence rates and determine long term freedom from AF following ablation of areas of high recurrence rates.

The objective of this study is to evaluate the safety, efficacy and efficiency of rapid anticoagulation reversal with protamine sulfate versus routine activated clotting time (ACT) monitoring in patients undergoing catheter based ablation of atrial fibrillation.