Active clinical trials for "Atrial Fibrillation"

Life-long therapy with oral anticoagulants (OAC) is strongly recommended in AF patients receiving left atrial appendage isolation (LAAI) to prevent thromboembolic (TE) events. However, some patients are observed to remain stroke-free while off OACs for years whereas others experience TE events if OAC is discontinued even for a short period of time. Therefore, we aim to evaluate the association of genetic variants (single nucleotide polymorphisms - SNPs) with off-anticoagulation stroke-risk in AF patients.

Implantable Loop Recorders (ILR) are small devices the size of a memory stick, which are implanted to investigate stroke, palpitations and fainting episodes. They monitor the heart constantly and detect abnormalities such as slow or fast heart beats and an irregular heartbeat called Atrial Fibrillation (AF). Stroke is a life threatening condition and no cause is identified for over 30% of strokes. AF is a predominant risk factor for stroke. About 30% of patients with stroke are found to have AF when they are monitored with an ILR. Unfortunately not every patient with a stroke can have an ILR; one of the prohibiting factors is cost. Therefore, there is an urgent unmet clinical need to rationalise the use of ILRs and prioritise their implantation in those patients that have most to gain and therefore achieving cost-effectiveness and improving patient care. In order to achieve the above, identifying parameters that can predict the presence of underlying AF is very important. Studies have shown that special factors including patient's other medical problems, family history, factors on paper recording of the electrical activity of the heart, heart monitors and ultrasound scan of the heart can be useful in predicting AF. Also certain blood molecules have been investigated as potential predictors of AF. The aim of this study is to look at all the above factors and combine them in order to determine whether these factors can predict the presence of AF. Identify predictors of AF will allow doctors to identify patients at different risk of having AF and use the ILR in all possible patients that might need it.

Investigate the compliance of oral anticoagulants in Chinese NVAF patients and find out the causes, so as to provide basis for formulating effective measures to improve the compliance of oral anticoagulants.

The purpose of this study is to assess pharmacokinetics and pharmacodynamics of Apixaban and clinical outcome of Apixaban in Thai patients with nonvalvular atrial fibrillation with varying degree of creatinine clearance

Early recurrence of cardioembolic stroke in patients with atrial fibrillation is common, reaching approximately 6% within 30 days after initial stroke. Therefore, it is preferable to provide early anticoagulation for cardioembolic stroke. However, early anticoagulation may increase the risk of hemorrhagic transformation of cerebral infarcts. It is difficult to decide the timing of initiation for anticoagulant therapy in stroke patients with non-valvular atrial fibrillation (NVAF). In 2013 the European Heart Rhythm Association presented the practical guides for oral anticoagulants in NVAF patients, which recommend that the optimal time to start anticoagulant therapy should be determined according to the stroke severity. However, this recommendation is principally an experts' opinion and is not suitable in the clinical practice in Japan. RELAXED, a multicenter observational study is planned to evaluate the efficacy and safety of an oral direct activated coagulation factor Xa inhibitor, rivaroxaban, for acute ischemic stroke patients with NVAF in consideration of the infarct size, timing of initiation for rivaroxaban medication, and other patient characteristics, and thereby to determine the optimal timing of the initiation during acute ischemic stroke. The consecutive acute ischemic stroke / transient ischemic attack (TIA) patients with NVAF who are treated with rivaroxaban will be enrolled. The infarction size at 0-48 hours after stroke onset will be measured by the diffusion weighted image (DWI) MRI. The primary efficacy endpoint is recurrent ischemic stroke within 3 months. The primary safety endpoint is major bleedings within 3 months. The optimal timing to initiate rivaroxaban during acute ischemic stroke is determined by analysis of co-relation between primary endpoints and the infarct size / time to initiate rivaroxaban.

Introduction - Pulmonary vein isolation (PVI) is the cornerstone of paroxysmal atrial fibrillation (AF) ablation. Recurrences remain, however, not infrequent and are mainly due to PVs reconnection. In this setting, all procedural means able to improve the quality of tissue lesions are welcome. Study Hypothesis - A continuous sensing of contact force (CF) during ablation, offered by a new catheter available on the market, was a valuable additional tool increasing the efficacy of the ablation procedure for PVI. Methods - Prospective observational non-randomized monocentric study. Patients with paroxysmal AF receive PVI following standard ablation procedures (linear antral catheter ablation guided by CARTO 3 System, Biosense Webster, Inc.) using either a new irrigated RF ablation catheter that provides tip-to-tissue CF information (THERMOCOOL SMARTTOUCH Catheter, Biosense Webster, Inc.) (CF group), or a non-CF irrigated catheter (THERMOCOOL SF or EZ STEER THERMOCOOL Catheter, Biosense Webster, Inc.) (control group). Overall, 60 consecutive patients are enrolled in the study, with 30 patients in each group. All procedures is performed by the same experienced operator, not blinded to the catheter used. Except for CF information (with an objective of at least 10 g, associated to the most perpendicular vector obtainable), ablation procedures are carried out using identical approaches in both groups. Patients are discharged from hospital free of antiarrhythmic therapy. Patients are enrolled in a specific follow-up plan. Primary Endpoints -(1) Proportion of PVI after exclusive anatomic approach, (2) Proportion of patients free of AF after 12-month follow-up.

The determination of the 2D6 genotype will enable us to determine the way flecainide is metabolized by the liver. Some individuals are poor metabolizers and some individuals are extensive metabolizers of the drug. This will also determine which patients will benefit from the drug.

The investigators aimed to use pharmacogenetic information in clinical practise which may lead to rapid, efficient, and safe warfarin dosing in this observational prospective study. In this context, the investigators plan to develop an algorithm for estimating the appropriate warfarin dose that is based on both clinical and genetic data from the Turkish study population. This study is unique not only investigating clinical factors, demographic variables, CYP2C9, and VKORC1 gene variations which contribute to the variability among patients in dose requirements for warfarin but also including thrombogenic single nucleotide polymorphisms (SNP) in the same patient population. Thus, warfarin would be a good example by being the first cardiovascular drug for pharmacogenetic guided "personalized medicine" applications.

Ablation of atrial fibrillation is standard therapy for symptomatic patients or patients with severely reduced systolic left ventricular ejection fraction. Complications of the procedure are ischemic thrombembolic stroke. Therefore periprocedural treatment with heparin is administered to acchieve a therapeutic anticoagulation. The efficacy of anticoagulation is measured by active-clotting time (ACT) which is measured with blood drawn mostly from the V. femoralis. Despite controlled anticoagulation periprocedural stroke is published with an incidence of up to 2% and asymptomatic cerebral embolization from 2% to 15%. The ACT-Trial has two aims: Analysis of the influence of the localization of blood drawing on the measured ACT: blood from central venous line, from LA and from LAA. Dependency of the ACT measured in the blood of the LAA with regard to anatomic und functional LAA-measurements. Patients will be included scheduled for left atrial ablation procedure and will be divided in two groups: atrial fibrillation at time of procedure and sinus rhythm at time of procedure.

This study is designed to look at the impact that support and motivation has on patients with Atrial Fibrillation's ability to lose weight and maintain this. We believe that weight loss has a positive impact on the reduction of symptoms of atrial fibrillation and can decrease the likelihood of the arrhythmia returning following cardio version. This study is designed for patients who have a diagnosis of Atrial Fibrillation and have a Body Mass Index greater than 27. In the study, we plan to provide support and motivation to patients with atrial fibrillation to encourage weight loss. There are several weight loss strategies available to follow. Information will be provided about each strategy to encourage informed choices. If the initial strategy chosen is not working, this can be change to a more suitable one as required. Follow up will be by telephone at 2 and 4 weeks then every month thereafter where you will be asked your weight and to clarify the weight loss strategy you are following. You will be seen at 6 and 12 months where you will have an ECG, BP check and your weight measured. A final telephone assessment will take place at 24 months. We hope that the research will in the future help patients with Atrial Fibrillation manage and maintain their weight loss to improve their symptoms and prevent recurrence of the arrhythmia. The results of this study could potentially change practice in our centre by providing more structured weight loss clinics for patients with Atrial Fibrillation