The Maintenance of Human Atrial Fibrillation

Inclusion Criteria

• •patients undergoing electrophysiology study (EPS) for ablation of (a) paroxysmal AF (non-rheumatic) whose AF episodes self-terminate in \< 7 days, or (b) persistent AF (non-rheumatic) whose AF episodes last \>or= 7 days but terminate with DC cardioversion or anti-arrhythmic drugs and do not recur within 24 hours.
• •AF patients must have failed \>or= 1 anti-arrhythmic drug
• •will have a full evaluation focusing on diabetes mellitus, hypertension, coronary disease, left ventricular ejection fraction (LVEF). We will document whether AF relates to times of vagal activity (meals or sleep) or exercise. We will record the use of drugs affecting the renin-aldosterone-angiotensin system (RAAS) and statins, that may protect against atrial fibrosis and AF. We will document serum potassium level, since slight elevations slow CV in vitro. We will record 12-lead ECG and echocardiography for left atrial diameter, and stress test and/or coronary angiography if indicated.
• •will have event monitor recordings with daily transmissions for at least one week to document AF burden (study subjects) or exclude AF (control subjects).
• •must have with-held amiodarone for \> 30 days and other anti-arrhythmic drugs for \> 5 half-lives.