Clinical Spectrum of Nodoventricular Accessory Pathways: An Asian Collaborative Study.

backgroundNodoventricular accessory pathways (NV-APs) are rare embryonic remnants connecting the atrioventricular node to the ventricle. We describe their electrophysiological characteristics and ablation outcomes across a multicenter Asian cohort, highlighting a developmental link to Ebstein anomaly. CASE SERIES: Five patients presented with supraventricular tachycardia due to NV-APs (4 concealed, 1 manifest). Programmed stimulation confirmed ventricular participation and excluded the atrium from the circuit. Two patients had Ebstein anomaly, clinically extending histological data regarding structural atrioventricular junctional abnormalities in the postnatal heart. Ablation targets varied significantly given diverse anatomical insertions. Mapping efforts were made to record AP potentials; a successful ablation site was achieved at the right infero-paraseptum in 3 patients guided by AP potentials, the left infero-paraseptum in 1 patient, and the supero-paraseptal region via the noncoronary aortic sinus in 1 patient.

conclusionThis series illustrates the clinical heterogeneity of NV-APs. Their presence in Ebstein anomaly represents a developmental association driven by tricuspid hinge and atrioventricular node axis displacement, requiring targeted mapping of discrete potentials. TAKE-HOME MESSAGES: Nodoventricular pathways exhibit significant anatomical heterogeneity, including a developmental link to Ebstein anomaly. Successful ablation requires precise mapping of discrete pathway potentials rather than generic regional ablation.