Typical atrial flutter ablation and the risk of postablation atrial fibrillation.

Typical atrial flutter is readily abolished by creating a line of block along the isthmus between the tricuspid annulus and the inferior vena cava. However, postablation atrial fibrillation occurs frequently, and its occurrence increases during the follow-up. Preablation atrial fibrillation is the most important risk factor for postablation atrial fibrillation occurrence. Among patients with preablation atrial fibrillation, patients with drug-induced atrial flutter present a lower risk of postablation atrial fibrillation than patients with spontaneous preablation atrial fibrillation. Patients with preablation lone atrial flutter also present a significant risk of atrial fibrillation development as time passes. Hence, they must be advised of the risk of recurrent symptoms and late atrial fibrillation, and closely followed up despite successful transisthmic ablation. Patients with atrial fibrillation after transcatheter isthmus ablation should be offered catheter-based pulmonary vein isolation, particularly if atrial fibrillation occurs despite continuation of antiarrhythmic drug therapy.