Symptomatic Premature Ventricular Contractions in the Context of Cardiac Memory Following Septal Accessory Pathway Ablation: A Case Report.

Introduction: Wolff-Parkinson-White (WPW) syndrome is a congenital heart disorder marked by an accessory electrical pathway (AP) causing reentrant tachycardias. This report presents a case of WPW successfully treated with catheter ablation but followed by transient symptomatic premature ventricular contractions (PVCs). Case Summary: A 27-year-old WPW patient was referred due to paroxysmal tachycardias. The baseline electrocardiogram confirmed ventricular pre-excitation, and the patient underwent radiofrequency ablation targeting a right septal AP. Some days later, the patient experienced palpitations distinct from preablation symptoms. A 24-h Holter ECG and exercise testing revealed frequent, monomorphic PVCs originating from the previously pre-excited region. Low-dose beta-blocker therapy alleviated symptoms, and there was no evidence of PVC recurrence after tapering temporary beta-blocker medication. Discussion: This case illustrates a new onset of PVC after ablation of septal AP in WPW syndrome. We postulate that transient electric instability due to AP-associated cardiac memory led to enhanced local automatic activity resulting in PVC.