Successful Targeted Ablation of the Pathway Potential in the Noncoronary Cusp of the Aortic Valve in an Infant with Incessant Orthodromic Atrioventricular Reentrant Tachycardia

A 4-month-old infant presented with incessant SVT and severe failure to thrive. At EP study, orthodromic-reciprocating tachycardia using an anteroseptal accessory pathway was identified. Detailed mapping on the right atrial septum failed to disclose a distinctly early site of atrial activation or a near-field pathway potential. Mapping in the noncoronary cusp of the aortic valve identified a discrete pathway potential that was successfully targeted for ablation. At 12-month follow-up after the procedure, there had been no recurrence of tachycardia. Conclusion: Myocardial fibers above the aortic valve cusps may constitute the atrioventricular bypass connection and can be identified and targeted for successful ablation even in infants. (J Cardiovasc Electrophysiol, Vol. 20, pp. 216-220, February 2009).