To demonstrate that the use of Contact Therapy™ Cool Path™ ablation catheter in conjunction with the EnSite Velocity Contact Technology for the treatment of typical atrial flutter

• Does not result into unacceptable risk of intra-procedural composite serious adverse events and,
• Does not affect efficacy of the ablation procedure The study will also evaluate the

This will be a prospective, multi-center and non-randomized study. All enrolled patients who meet the eligibility criteria will receive ablation therapy for typical atrial flutter using the Contact Therapy™ Cool Path™ Cardiac Ablation System. Historical data from published (PMA P060019 Cool Path) , reported (IDE G090109 Cool Path Duo) and published literature on Atrial Flutter RF ablation studies is used to determine performance goals for primary study endpoints and derive the sample size. In addition, the following analyses will be performed in the study

1. Validation of ECI against conventional methods of assessing tip tissue contact and

2. Ancillary analysis to assess the relationship between the ECI and study outcomes. Subjects will undergo two follow up visits at day 10 and month 3 post procedure. The following assessments will be performed during these visits:

   • ECG
   • Query regarding adverse events since the last visit
   • Assessment of anti-arrhythmic and anti-coagulation medication
   • Query regarding recurrence or repeat ablation for typical atrial flutter

Inclusion Criteria:

• A signed written Informed Consent
• Presence of typical atrial flutter (cavo-tricuspid isthmus dependent)
• If subjects are receiving antiarrhythmic drug therapy (Class I or Class III AAD) for an arrhythmia other than typical atrial flutter, then they need to be controlled on their medication for at least 3 months. If a subject had typical atrial flutter before starting the AAD(s) (Class I or Class III) and then subsequently had another arrhythmia (i.e. atrial fibrillation), then the 3 month AAD criteria will not apply.
• One documented occurrence of the study arrhythmia documented by ECG, Holter, telemetry strip, or transtelephonic monitor within the past 6 months
• In good physical health
• 18 years of age or older
• Agree to comply with follow-up visits and evaluation

Exclusion Criteria:

• Prior typical atrial flutter ablation treatment
• Pregnancy
• Atypical flutter or scar flutter (non isthmus dependent)
• Significant coronary heart disease or heart failure; that is unstable angina pectoris and/or uncontrolled congestive heart failure (NYHA Class III or IV) at the time of enrollment
• A recent myocardial infarction within 3 months of the intended procedure date
• Permanent coronary sinus pacing lead
• Clinically significant tricuspid valvular disease requiring surgery and/or a prosthetic tricuspid heart valve.
• Evidence of intracardiac thrombus or a history of clotting disorders
• Participation in another investigational study
• Cardiac surgery within 1 month prior to the intended procedure date
• Allergy or contraindication to Heparin