Inter-atrial septum dissection during atrial fibrillation ablation via atrial septal defect: A rare complication

<h2>Abstract</h2> Catheter ablation has become an established treatment modality for atrial fibrillation (AF), particularly in patients with refractory or intolerant responses to medical therapy¹. The Marshall-Plan has garnered interest in this field for its ability to achieve durable posterior mitral isthmus ablation². This anatomically based approach combines alcohol ablation of the vein of Marshall with pulmonary vein isolation, mitral roof and isthmus ablation, and a cavotricuspid isthmus line. Despite its effectiveness, procedural complications, although rare, must be considered^3,4. Here, we report a case of suspected inter-atrial septum (IAS) dissection during Marshall-Plan AF ablation, complicated by the development of a saline transudative pericardial effusion. The study adheres to the Declaration of Helsinki.