Atrial Flutter Ablation in the iCMR

Inclusion Criteria:

• Patient indicated for type I atrial flutter ablations with at least 1 documentedepisode of type I atrial flutter within 6 months (180 days) of enrollment

• Patient 18 years and older

Exclusion Criteria:

• Contraindications for MRI procedures

• Patients who cannot have anti-arrhythmic drugs (class I or class III) prescribed forthe treatment of type I atrial flutter stopped on the day of the procedure

• Previous CTI ablation procedures

• Myocardial infarction within 60 days of enrollment

• Current unstable angina

• Cardiac surgery within 90 days of enrollment

• Any cerebral ischemic event (including transient ischemic attacks) within 6 months (180 days) of enrollment

• Thrombocytosis or thrombocytopenia

• Contraindication to anticoagulation therapy

• Currently documented intracardiac thrombus or myxoma

• Implantation of permanent leads of an implantable device in or through the rightatrium within 90 days of enrollment

• Prosthetic valve through which the catheter must pass

• Interatrial baffle or patch through which the catheter must pass

• Moderate or severe tricuspid valve regurgitation or stenosis

• Uncompensated congestive heart failure

• Active systemic infection

• Pregnancy or if subject plans to become pregnant during the trial

• Uncontrolled hyperthyroidism

• Any other significant uncontrolled or unstable medical condition

• Enrollment in any concurrent study without Imricor written approval

• Life expectancy of less than or equal to 2 years (730 days) per physician opinion