Active clinical trials for "Atrial Fibrillation"

The purpose of this study is to demonstrate whether renal sympathetic denervation is safe and effective in patients with hypertension and paroxysmal atrial fibrillation.

Atrial fibrillation (AF) affects as many as 1 in 16 people over the age of 65 and reduces the quality of life of large numbers of people in the UK and around the world. Catheter ablation is a minimally invasive treatment that has been developed to help eliminate AF. Recent studies have identified that a particular area of the heart, namely the left atrial appendage (LAA), which is a pouch in the left atrium (small collecting chamber of the heart), may be the main source of AF in many cases. There is a clear lack of knowledge about the structure, anatomy, function and electrical properties of the LAA, which is fundamental to furthering our understanding and management of AF. In addition, it is well known that AF significantly increases the risk of stroke. The majority of strokes occur due to blood clots forming in the LAA. Traditionally, the most effective treatment to minimise the risk of stroke has been to thin the blood with agents such as warfarin. This therapy requires regular blood tests at much inconvenience to patients and increases the risk of bleeding complications. Recently, a large study demonstrated that use of an implanted device (Watchman®) to occlude the LAA is as effective as warfarin in preventing stroke and confers a lower mortality rate. We aim to investigate whether it is safe and feasible to ablate the LAA and to implant a Watchman® device during the same procedure in patients who are in atrial fibrillation all of the time.

Prospective and explorative clinical study. The objective is to assess the clinical efficacy of pulmonary vein isolation using the Arctic Front Advance cryoballoon in patients with longstanding persistent atrial fibrillation (AF) at one year follow up. 44 subjects will be enrolled. Patients with longstanding persistent AF, with continuous AF duration longer than one year, who have not previously undergone an AF ablation procedure, and have symptoms related to AF corresponding to at least European Heart Rhythm Association (EHRA) score 2, will be studied. Patients should have failed at least one betablocker or class I or III antiarrhythmic drug. Excluded are those with congestive heart failure with New York Heart Association (NYHA) class 3 or more, left ventricular ejection fraction < 40%, left atrial diameter ≥ 60 mm, significant valvular disease or planned cardiac intervention within next 12 months, and conventional contraindications for AF ablation procedures. Patients will be screened with echocardiography and response to electrical cardioversion. Following conversion to sinus rhythm, amiodarone will be initiated to maintain sinus rhythm. Pulmonary vein isolation will be performed using the Arctic Front Advance cryoballoon ablation catheter. Pulmonary vein conduction block will be assessed by a circular mapping catheter. All patients will be subject to electroanatomical voltage mapping during sinus rhythm for demonstration of extent of atrial myocardial lesions after ablation. Patients will be followed every third month up to one year after the ablation procedure. Arrhythmia monitoring during follow up will be performed by 7 day Holter monitoring at 6, 9 and 12 months follow up, including a 12 lead ECG. 12 months follow up for symptoms, EHRA score, and quality of life. Patients with symptomatic recurrence requiring a redo ablation procedure will be re-studied after 8-12 months while asymptomatic patients will be studied at 12 months follow up. Primary end-Point is Clinical success based on symptoms and presence of AF. Secondary end-Points include freedom from AF without antiarrhythmic drugs at 6 and 12 months according to 7 day Holter and ECG, Rhythm, AF burden, AF profile, Quality of Life, Symptoms, Adverse Events, atrial size and function, Biomarkers, extent of scar tissue, predictive factors of freedom from AF, complications, hospitalization and Health economics.

The purpose of this study is to compare the efficacy and safety of PV isolation with continued antiarrhythmic drug treatment (PVI+ADT) to PV isolation without continued ADT (PVI-ADT) in patients undergoing treatment for symptomatic recurrent AF.

The study aims to compare the results of pulmonary vein isolation (PVI) with a single technology approach in patients suffering from paroxysmal atrial fibrillation (PAF) with patients who have persistent AF of less than 3 months. Many studies have shown that electrical reconnection of the pulmonary veins following the index procedure can occur in up to 40% of targeted veins leading to a recurrence of PAF. Endoscopically guided laser ablation utilising the HeartLight system (CardioFocus Inc., USA) has been shown to be safe and effective and has also shown promising rates of durable isolation compared to point by point radio frequency techniques. However, the impact of employing this technique for patients with persistent AF has not yet been reported. The study hypothesis is that there will be no statistically significant difference between the results of PVI in the two groups of patients.

The investigators are evaluating the effect of Pradaxa in comparison to warfarin on bone turnover and bone density in men and women with atrial fibrillation.

Atrial fibrillation (AF) is the most common heart arrhythmia. Many people do not have symptoms and are not aware they have AF. Others may feel dizzy, short of breath, feel very tired and become aware of a fast and irregular heart beat (palpitations). The main complication of AF is an increased risk of stroke and incidence of heart failure. There are two key aspects of treatment for AF. The first is protection from stroke, treated with oral anticoagulants. Treatment of AF is either by controlling the rate (frequency of contraction) or controlling the rhythm (restoring regular contraction). Rate-control is generally employed first with an intent to reduce the rate at which the lower pumping chambers contract and improve their efficiency. Appropriate medication is used and with this treatment strategy it is accepted that AF will be present as the long term heart rhythm. If symptoms persist despite medication the preferred strategy is to restore sinus rhythm (SR) and regular contraction in all pumping chambers of the heart. This can be done with electric shock treatment (DC cardioversion) together with long-term tablet medication, or by a more definitive 'cauterisation' therapy (catheter or thoracoscopic surgical ablation). In this study the investigators will study patients with symptomatic long standing persistent AF (continuous AF for more than 1 year) who have tried and failed drug and/or electrical therapy. At present the investigators do not know what the best ablation technique is for treating symptomatic, long-standing persistent AF (LSPAF). Catheter ablation (CA) is the most widely available invasive treatment available for AF. Thoracoscopic surgical ablation (SA) is not widely available but our hospitals have the expertise to conduct this procedure. CA has been shown to achieve modest degrees of success in restoring normal SR with the caveat that most patients do require 'multiple' procedures (usually two or three). SA offers patients an alternative choice of therapy with a keyhole surgical thoracoscopic) approach. It may have a higher single procedure success rate although there is the potential for greater complication rates. The investigators aim to examine this in detail to help us understand which approach might be better for managing LSPAF.

The aim of this trial is to evaluate the effect of acupuncture on prevention of atrial fibrillation (AF) recurrence after electrical cardioversion (EC) for persistent AF patients resistant to the antiarrhythmic drugs (AADs).

Treatment of (long-standing) persistent atrial fibrillation (AF) remains cumbersome and the surgical (epicardial) approach seems to be the most effective. Still, however a significant amount of failures exist which is mostly due to incompleteness of the surgical ablation lines. Checking, and if necessary additional ablation, of these lines afterwards endocardially by the cardiologist (the so-called serial hybrid approach) could overcome this problem.

There are multiple important factors which need to be monitored when conducting ablation for atrial fibrillation. The contact between the catheter tip and the inside of the heart wall is now measurable and may improve the effectiveness of catheter ablation for atrial fibrillation patients.