Active clinical trials for "Atrial Fibrillation"

Heart failure is a clinical syndrome where the heart is unable to pump enough blood to satisfy the organism's metabolic needs. Heart failure has become a major clinical and public health problem with approximately 300,000 Canadians being affected. Atrial fibrillation is a rhythm disorder in which the upper chambers of the heart (the atria) are paralyzed by continuous electrical activity. Some of the continuous chaotic electrical activity in the atria travels to the lower cavities of the heart (the ventricles) causing then to beat irregularly and very rapidly. It is the most frequent cardiac arrhythmia, affecting 5% of individuals 65 years and older and it is associated with an increased risk of stroke. Both conditions (heart failure and atrial fibrillation) often co-exist in the same patient. Heart failure promotes atrial fibrillation and atrial fibrillation aggravates heart failure. The Atrial Fibrillation and Congestive Heart Failure (AF-CHF) trial is investigating whether preservation of normal cardiac rhythm influences mortality and morbidity. The AF-CHF study began in 2001 and 1,378 patients have been enrolled from 123 participating centres, in North America, South America, Europe, and Israel. The results of this trial which are expected in October 2007, will improve decision-making for the physician and will provide useful information to healthcare organizations responsible for the care of heart failure patients.

The purpose of this study is to characterise which fractionated electrogram morphologies are important to target in the catheter ablation of atrial fibrillation.

Atrial fibrillation is a common form of heart rhythm disturbance that for some patients is treated by catheter ablation (making an ablation lesion or burn inside the heart using a fine wire (catheter)). A new system for manipulating the catheters has recently been introduced into clinical practice (the Amigo Remote Catheter System (RCS)). This trial is designed to answer two primary questions: a) is the contact force (the force with which the catheter comes into contact with the heart) any different using the RCS to manual techniques,and b)are the resulting ablation lesions within the heart any different in terms of the volume and contiguity of the lesions produced. Additionally the investigators aim to determine how the two techniques compare in success (the proportion of patients whose heart rhythm disturbance is corrected by the procedure).

Study design: Randomized prospective comparison of pulmonary vein isolation alone versus a strategy aiming for atrial fibrillation termination by using a stepwise approach consisting of pulmonary vein isolation, biatrial defragmentation aiming for fractionated electrograms and linear ablation if required.

In this multi centre pilot study we will perform TEE in patients with AF who are eligible for VKA treatment. TTE will be used as pre-screening: if TTE shows left atrial abnormalities or aortic plaque, patients will be excluded from randomisation. TEE will be performed in all other patients to detect or exclude complex aorta plaques or signs of left atrial stasis. Three hundred patients who do not have these features on TTE will be randomly assigned to treatment with aspirin or VKA. Follow-up will be 1 year.

Hypothesis: Blocking the angiotensin (AT) II type 1 receptor (Olmesartan) reduces the incidence of episodes of atrial fibrillation in patients with paroxysmal atrial fibrillation during 12 months by more than 25% compared to standard medication without angiotensin II type 1 receptor. A total of 422 subjects will be included in the two study groups. The treatment arm will receive 40mg Olmesartan per day, the remaining patients will receive placebo. Follow-up is 12 months. Daily Tele-ECG recordings will determine the cardiac rhythm and asymptomatic episodes of atrial fibrillation (AF) every day. Concomitant therapy with AV-nodal blocking drugs are allowed during the study. In case of severe AF-induced symptoms, an antiarrhythmic "recovery medication" (amiodarone) is allowed during follow-up.

Assess the clinical safety and feasibility of MultiPulse Therapy (MPT) electrical stimulation waveform sequence in terminating paroxysmal and persistent atrial fibrillation.

To determine the effect of our compound (BMS-919373) on electrical activity of the heart using pacemakers.

Clinical study intended to evaluate the feasibility of a new irrigated RF ablation catheter that allows the physiologist to perform a regular RF ablation procedure while it is being monitored through an imaging technique known as Optical Coherence Reflectometry (OCR). This technique is based upon the use of infrared light; it is innocuous for the human body and allows for the detection of the contact between the catheter tip with the tissue besides the lesion formation during the Radiofrequency (RF) application as the OCR technique is able to distinguish between ablated tissue and healthy tissue. Both features are able to provide a better control of the ablation procedure, which may become in a better clinical result in cardiac ablation procedures, especially in Atrial Fibrillation cases.

This study will create a computer program that can be used to help dose a drug called warfarin for the prevention of blood clotting. The study will collected specific information about those patients receiving this drug and use that information to create a computer program that will predict the effects of the drug. With this prediction program in place, the investigators can perform a series of "what if I gave this amount of drug" simulations to determine the best dose of drug for that patient. Once the computer programs are developed, the investigators will test the program in patients that actually need this drug. They will also include genetic information into the prediction since it has been shown that this information can affect how well the drug works. Patients will have this genetic information determined during this study.