Typical flutter ablation location is in the which region?

• A. Cavotricuspid Isthmus
• B. Interatrial Septum
• C. Left Atrial Appendage
• D. Coronary Sinus Ostium

Answer: (A)

Typical flutter is a macro-reentrant rhythm that travels around the tricuspid valve in the right atrium. The crucial path for this circuit is the cavotricuspid isthmus—the narrow area between the inferior vena cava opening and the tricuspid annulus. Ablation targets this isthmus to create a complete, bidirectional block, which interrupts the reentrant circuit and prevents the flutter from sustaining itself.

Because the flutter circuit relies on that corridor, the cavotricuspid isthmus is the most effective site to ablate. Other regions don’t form the main reentrant path: the interatrial septum isn’t the critical corridor for typical flutter, the left atrial appendage isn’t involved in this right atrial flutter circuit, and while the coronary sinus ostium is a nearby landmark, it isn’t the key path that sustains typical flutter.