Clinical Research Directory

Inclusion Criteria: * Patients must be at least 21 years old at the time of enrollment. * Patients must be able to give informed consent. * Patients with symptomatic paroxysmal/persistent atrial fibrillation (AF). * Eligible patients must be determined to be suitable candidates for ablation to treat AF by their cardiologist and/or electrophysiologists regardless of this protocol. * Patients are scheduled to have a pre-procedure cardiac CT upon the discretion of their electrophysiologists Exclusion Criteria: * Known allergy to iodinated contrast media. * Elevated serum creatinine (\> 1.5mg/dl) OR calculated creatinine clearance of \< 60 ml/min (using the Cockcroft-Gault formula). * Patients with a positive urine or serum pregnancy test will be excluded from this study. * Patients with heart transplantation. * Patients with polymorphic ventricular tachycardia (VT) or presenting in electrical storm. * Presence of any other history or condition that the investigator feels would be problematic. * Patient with iodinated contrast administration for other reason 24 hours prior to investigational CT. * Patients who have a heart pacemaker, metallic foreign body (metal sliver) in their eye, or who have an aneurysm clip in their brain, mechanical heart valves and prosthetics that contain metal. * Patients with severe claustrophobia.