Successful ablation of lower loop re-entry after Starnes procedure in an infant with severe tricuspid valve dysplasia: a case report

Background: Tricuspid valve dysplasia (TVD) is a rare right-sided congenital heart disease characterized by severe tricuspid regurgitation and right atrial enlargement, which may predispose to atrial arrhythmias. In severe neonatal cases, the Starnes procedure can be life-saving, but postoperative anatomical alterations may complicate subsequent arrhythmia management. Case summary: A 2-month-old female infant with TVD and pulmonary atresia developed drug-refractory atypical atrial flutter after the Starnes procedure. Three-dimensional electroanatomical mapping identified lower loop re-entry involving the cavotricuspid isthmus (CTI). Radiofrequency catheter ablation across the CTI successfully terminated the tachycardia. However, atypical flutter recurred 1 week later. During subsequent systemic pulmonary shunt surgery, additional surgical ablation was performed using the prior catheter ablation site as an anatomical landmark. After detaching the tricuspid valve patch, the CTI line was extended to the tricuspid annulus, resulting in complete arrhythmia control. Discussion: The outcome of this case suggests that foetal-onset volume overload from severe tricuspid regurgitation may promote early atrial remodelling and arrhythmogenic substrate formation in TVD. Although CTI ablation after the Starnes procedure may be feasible in a small infant, patch-related anatomic barriers may prevent complete lesion formation. Prior catheter ablation sites may be useful intraoperative landmarks for successful surgical ablation.