Epicardial left atrial appendage and biatrial appendage accessory pathways

Background: Acute success rates of accessory pathway ablation for Wolff-Parkinson-White (WPW) syndrome can exceed 95%, with rare failures attributed to anatomically complex epicardial connections. Right atrial appendage to right ventricle pathways have been reported, but their left-sided counterparts have only recently been described.

Objective: The purpose of this study was to report three unique cases of WPW syndrome in children with left atrial appendage and biatrial appendage connections.

Results: Three young patients with high-risk accessory pathways (accessory pathway effective refractory period = 190-240 ms) had unsuccessful endocardial ablations despite aggressive efforts with various catheter techniques. One patient had a left atrial appendage to left ventricular connection; the other two had biatrial appendage pathways connected to their respective ventricular surfaces. The latter two patients had a history of ventricular fibrillation: one experiencing ventricular fibrillation in the electrophysiology laboratory and the other suffering from ventricular fibrillation arrest at home. All three patients were taken to the operating room, where the appendages were noted to be diffusely adherent to their ventricles by fibrofatty connections. Dissection of the appendages led to loss of preexcitation and no further tachycardia.

Conclusion: Surgical management of atrial appendage accessory pathways should be considered if aggressive attempts at endocardial ablation have failed.