Recording for Potential AF Drivers and Patient Specific Atrial Anatomy & Atrial Electrogram Maps

Inclusion Criteria: * Patients at VCU Medical Center who are 21 years or older undergoing EPS for ablation of persistent AF (non-rheumatic) whose AF episodes last equal to or greater than 7 days but terminate with DC cardioversion or anti-arrhythmic drugs and do not recur within 24 hours. * Per current standard of care, AF patients must have failed equal to or greater than 1 anti-arrhythmic drug to qualify for ablation. Exclusion Criteria: * Active coronary ischemic in the past year * Rheumatic valve disease, that leads to distinct AF and increases thromboembolic risk * Prior ablation or cardiac surgery, that alters atrial electophysiology * Left atrial clot or dense contrast on TEE, which would increase thromboembolic risk * Out of range serum electrolytes, including K outside 4.0-5.0 mmol/1 * Left atrial diameter greater than 60 mm, to exclude extreme structural remodeling and failure to maintain sinus rhythm * Thrombotic disease, venous filters, transient ischemic attack or cerebrovascular accident, to minimize additional risk * Pregnancy * Inability or unwillingness to provide informed consent * Unable to converse in English * Use of anti-arrhythmic drug less than 5 X half-life Prior ablation or cardiac surgery, that alters atrial electophysiology