Active clinical trials for "Atrial Fibrillation"

The clinical effects of intra-operative radiofrequency ablation in patients with persistent or permanent atrial fibrillation and an indication for an implantation of a heart valve prosthesis or coronary bypass surgery are the purposes of this study. The study will examine if and to what extent the quality of life and the use of medical care differs between patients with and without ablation. Furthermore, there will be thorough echocardiographic examinations of the heart to detect differences between the different treatment groups. The patients will be followed for one year after treatment.

This study aims to guide participants in recognizing their OSA (obstructive sleep apnea) and AFib (atrial fibrillation) symptoms, realizing what medical conditions can cause these symptoms (if any) and inform the participants on their possible diagnosis

This is a study looking at the feasibility of conducting a larger definitive research trial looking at the effectiveness of high intensity interval training in individuals who are scheduled for electro-cardioversion. Usual care for these participants is to go home and continue with their typical daily routine. The investigators will test whether participating in 3-weeks of thrice-weekly high intensity interval training before electro-cardioversion can lengthen the time to recurrence of atrial fibrillation after electro-cardioversion in these individuals. Participants will be asked to come to the University of Ottawa Heart Institute for a baseline visit at which fitness (cycle ergometer), body composition (weight, height, waist circumference and percentage body fat), heart rate variability and habitual exercise levels will be measured. Participants will then be randomized to either the exercise group or the usual care group. Those randomized to the usual care group will go home for 3-weeks and continue with their typical daily routine. Those randomized to the exercise group will return to the Heart Institute three times per week for 3-weeks to participate in a high intensity interval training program prior to their electro-cardioversion. All participants will be asked to measure daily heart rate and rhythm using the AliveCor system which is compatible with their Smartphones, for up to 12-months following their electro-cardioversion. All participants will be asked to return at 3-weeks (and prior to their electro-cardioversion) to measure fitness (cycle ergometer), body composition (weight, height, waist circumference and percentage body fat), and habitual exercise levels. The entire study should last approximately 24-months. Participants will be involved for 52-weeks. The investigators are looking to recruit 20 participants total for the feasibility trial. The investigators hypothesize that recruitment rates, drop-out rates, and adherence to the intervention will support a larger definitive trial.

Assess the subject acceptance of MPT, using therapy parameters that have been shown to be effective in terminating episodes of atrial fibrillation.

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

The objective of this study is to determine the safety of discontinuing oral anticoagulation therapy in high risk patients who have had a successful cardiac ablation and remain AF recurrence free for 3 months post ablation.

In the present application, we propose to refine and extend current insight into AAF mechanism and therapy by examining the importance of pharmacologic RAAS inhibition, ACE genotype, and their interaction in secondary AF prevention. We have 3 specific aims: To confirm that RAAS inhibition therapy reduces the incidence of AF recurrence. To test the hypothesis that the incidence of AF recurrence in the absence of RAAS inhibition therapy is higher among patients with the D allele. To explore the hypothesis that RAAS inhibition therapy is more effective for preventing AF recurrence in patients with the DD genotype than in those with DI or II genotypes.

This trial evaluates the safety and effectiveness of catheter ablation for PAF. The investigational catheter being studied is the NAVISTAR® THERMOCOOL® irrigated-tip catheter. At the time of this study, the NAVISTAR® THERMOCOOL® Catheter was FDA-approved for commercial distribution in the U.S. for treating patients with Type I atrial flutter and drug refractory monomorphic sustained ventricular tachycardia post myocardial infarction. The catheter was approved for use in Europe for endocardial ablation for treating cardiac arrhythmias.

There is accumulating evidence for obstructive sleep apnea (OSA) as an independent risk factor for paroxysmal atrial fibrillation and for high recurrence rates of atrial fibrillation after ablation therapy. We have previously shown that simulated OSA triggers premature atrial beats (PABs) by acute changes in intra-thoracic pressure. Most episodes of atrial fibrillation are initiated by PABs. However, the origin of PABs induced by intra-thoracic pressure swings is unknown. This study investigates the origin of premature atrial beats induced by intra-thoracic pressure changes that simulate obstructive sleep apnea in patients with atrial fibrillation.

Coronary artery bypass grafting (CABG) is the most common procedure performed by cardiac surgeons. Post-operative atrial fibrillation (AF) is the most common adverse event following CABG, experienced in 20-50% of patients; the highest incidence of AF occurs by the third post-operative day. Reduction of AF by various drugs is moderately effective, but involves either rate control with beta blockers or rate conversion with amiodarone after the myocardial damage processes initiating AF have already occurred. Decreasing the incidence of post-operative AF, and hence the morbidity and mortality of high-risk CABG patients, could be more fruitfully approached by targeting the upstream combined processes of inflammation and coagulation activation induced by the surgical insult and associated ischemia-reperfusion (I/R). We propose that cell damage induced by oxidative stress and I/R injury could be prevented and/or inhibited by antioxidant supplementation. Specifically the investigators hypothesize that high-dose intravenous (IV) vitamin C supplementation will ameliorate ROS and therefore damp down upstream inflammatory processes, leading to a reduction of downstream adverse events with demonstrable links to inflammation processes, such as AF.