Active clinical trials for "Atrial Fibrillation"

The purpose of this study is to determine the efficacy of Magnesium sulphate for the rate and rhythm control of the new onset (within 48 hours) atrial fibrillation in the hemodynamically unstable patients, admitted in the medical intensive care unit patients.

We conduct a randomized study comparing the safety and effectiveness of two interventional ablation techniques for treatment of paroxysmal atrial fibrillation: the segmental pulmonary vein ablation approach, (1) with empiric isolation of all pulmonary veins or (2) Segmental Isolation of the arrhythmogenic pulmonary vein(s)

Experimental data suggest that angiotensin II-antagonists reduce the atrial expression of prothrombotic adhesion molecules and oxidative stress parameters. The present study is designed to investigate the effects on angiotensin II-antagonist irbesartan to reduce the amounts of circulating oxidative stress markers and adhesion molecules in patients with persistent atrial fibrillation.

Transvenous pulmonary vein (PV) isolation using radiofrequency energy is an effective treatment for atrial fibrillation (1-4). However, rare but potentially life threatening complications such as thromboembolism (5), PV stenosis (5-10), left atrium-oesophageal fistula (11) and inflammatory syndromes (12) have been described. In preliminary studies an alternate approach using cryoenergy induces less endothelial disruption/ thrombus formation (13), preserves the extra cellular matrix and creates lesions with well-delineated border zones (14). Therefore, cryoenergy seems to be the ideal form of energy to safely perform PV isolation. We therefore hypothesise that in the setting of PV isolation for the treatment of atrial fibrillation (AF) cryoenergy is less traumatic and therefore reduces systemic inflammatory responses compared to radiofrequency energy. 78 patients presenting with symptomatic intermittent or persistent AF will be randomised to PV isolation with either radiofrequency (26 patients open irrigated tip, 26 patients closed irrigated tip) or cryoenergy (26 patients with cryoballoon). Systemic markers of cell damage and inflammatory response (t-troponin, CK, CK-MB, vWF, PAI-1, micro particles, platelet activation/overall function, CRP, IL-6, IL-8, IL-10, TNF alpha, procalcitonin) will be monitored before, during and 48h after the procedure. Further endpoints include time to PV-isolation and procedure related complications. Six month clinical follow-up will focus on freedom from AF and cardiovascular events.

Atrial fibrillation (AF) is a common supraventricular arrhythmia, the incidence of which increases with age. The aim of treatment of atrial fibrillation is to restore sinus rhythm and return the heart to atrioventricular synchrony, avoiding the risk of thromboembolism. The fact that pharmacological therapy of AF is at best 50% effective has led to a search for surgical approaches over the last 20 years. Maze procedure was a classic method to treat AF. However, it is such a complex procedure that very few surgeons have adopted it. A few minimally invasive procedures to create transmural lesions which mimic MAZE procedure have been introduced. One of the mostly favored methods is catheter-based radiofrequency ablation, another one is video assisted epicardial radiofrequency ablation through small thoracic incisions in operating room. Recently, we invented an epicardial radiofrequency ablation method under totally thoracoscope, which further minimized the surgery trauma and increased the cosmetic effect.

The purpose of the investigators study is to investigate the correlation between naturally occurring chemicals, called reactive oxygen species (ROS), in the blood of human patients and the development of an abnormal heart rhythm, known as atrial fibrillation (AF). The development of atrial fibrillation is associated with increased medical problems like stroke. Many factors seem to cause the development of AF, and this rhythm occurs frequently after open heart surgery. When patients develop AF after cardiac surgery they are at increased risk for cognitive changes, infections, the development of kidney failure, and increased length of hospitalization. ROS are chemicals in blood and tissues that tend to cause microscopic blood vessel and heart damage. These chemicals occur naturally as the result of chemical reactions that occur in states of stress and inflammation, like tissue trauma and as the result of smoking. Patients who undergo cardiac surgery may have higher levels of ROS because of their underlying medical conditions. In addition, the organized tissue trauma that occurs in the setting of surgery may serve to increase ROS levels further. In turn, the higher ROS levels may put patients at even higher risk for the development of AF. The investigators believe that increased levels of ROS may help potentiate a patient's development of AF. Accordingly the investigators aim to measure ROS levels before and after surgery to see if there are particular levels that predict the development of this abnormal heart rhythm. By developing a better knowledge of the relationship between ROS and AF, the investigators hope to better understand another possible method of detecting patients who are at the highest risk of developing AF before it occurs after surgery. If these patients are better identified, this may eventually lead to medical treatment to prevent AF; and hopefully this will result in a decrease of the malicious effects that result from developing this abnormal heart rhythm.

Atrial fibrillation (AF) is the commonest condition affecting the rhythm of the heart. Tablets to try to normalise the heart rhythm rarely work well. As a result, doctors have devised a treatment called catheter ablation in which special wires are used to deliver heat energy (called ablation lesions) on the inside surface of the heart. Unfortunately, in many patients (almost 1 in 2), some of these ablation lesions recover, and this leads to AF recurrence. Many of these patients then need a second procedure to deliver further ablation at these recovered areas. Recent research has shown that monitoring of heat delivery with a factor called Ablation Index may be useful in predicting which ablation lesions are less likely to recover. Therefore, we aim to carry out AF ablation guided with Ablation Index (AI) and observe whether this will be associated with better durability of ablation lesions, and thereby better freedom from AF. This study will include patients with persistent AF, those whose AF episode(s) last for longer than seven days. All patients participating in the study will undergo an initial ablation treatment guided by ablation Index . All patients will undergo a repeat procedure 8-10 weeks after their initial treatment. Any gaps found during the second procedure will be closed again by delivery of ablation. All participants will be issued with a simple to use handheld heart rhythm monitor, and asked to make a 30-second recording of their heart rhythm each day and also whenever they have symptoms. The monitor stores these recordings and they will be downloaded at review appointments arranged 6 weeks, 3 months, 6 months and 12 months after the initial ablation procedure.

This is a single-center, randomized, two treatment groups, open, phase IV clinical study in subjects with atrial fibrillation and left atrial thrombus. At Visit 0 (Screening Visit) subjects with left atrial thrombus established in transesophageal echocardiography (TEE) are eligible to entry in the study. If the subjects fulfill all other in- and exclusion criteria and undersign the informed consent the baseline cranial magnet resonance imaging (MRI) can be performed followed by randomization to one of the two treatment groups (Phenprocoumon or Dabigatran) at Visit 1 (Baseline Visit). The subjects will be treated for 12 months with Phenprocoumon (INR adjusted once daily) or Dabigatran 150 mg twice daily. Routinely clinical follow up visits will be done at week 4, month 3, month 6, month 9 and month 12. Follow up TEE will be performed after 4 weeks and after 12 months also the follow up cranial MRI at this visit. If the subject was randomized in the VKA group routinely INR measurements will performed.

Use of higher energy doses (120-150 J) may not offer additional benefits and higher success rate compared with low to moderate initial energy (100-120 J) of biphasic shock for atrial fibrillation cardioversion. In this prospective open-label randomized trial consecutive patients with AF and candidate to AF electrical cardioversion will be randomized to receive 100J or 120 J as initial dose of biphasic shock. Patients will be also randomized in each group to anterolateral or postero-anteriore placement of defibrillator electrodes.

The purpose of this study is to determine whether left atrium substrate based ablation plus circumferential is effective in the treatment of persistent and long-standing atrial fibrillation.