This clinical investigation utilizes the Constellation Full Contact Mapping catheter in the left and right atria to explore atrial signal characteristics that can guide atrial fibrillation and atrial flutter ablation procedures more effectively.

Atrial fibrillation (AF) and atrial flutter (AFL) are the most common cardiac arrhythmias in adults, and account for a substantial portion of patient morbidity and healthcare expenditures. Great effort has been put forth to discover effective treatments for AF/FL. Promising results of catheter ablation suggest that AF/FL may be eliminated in a majority of patients. For example, data from numerous laboratories shows that up to 85 percent of patients with the paroxysmal form of AF may be free of recurrences and off anti-arrhythmic drugs at one year follow-up.

Inclusion Criteria:

Patients referred to the PI (Dr. Biviano) or co-investigators in the Program of Cardiac Electrophysiology at Columbia University Medical Center who are scheduled to undergo ablation will be approached for recruitment:

• Older than 45 years of age
• History of AF and/or AFL and are candidates for catheter ablation.

Exclusion Criteria:

Patients not fitting the above clinical criteria or unwilling to comply with the instructions of the monitor are excluded, as well as patients with the following:

• Permanent leads or prosthetic or stenotic valves present
• Active systemic infection
• Echocardiographically-confirmed visual presence of thrombus
• For whom the inability of obtaining vascular access exists
• Heparin-induced thrombocytopenia
• Hemodynamic instability or shock

Due to the paucity and lack of quality of intracardiac electrogram information collected from the one patient for whom the catheter was used in the left atrium, the collected electrogram data were not analyzed further.

Potential adverse events were collected at time of catheter insertion up to 1 day after procedure.