Three-dimensional electroanatomical mapping for atrioventricular nodal reentrant tachycardia associated with persistent left superior vena cava

Background: The anatomical courses of the slow pathway and His bundle are altered in patients with atrioventricular nodal reentrant tachycardia (AVNRT) associated with persistent left superior vena cava (PLSVC). We report a case of successful catheter ablation in such a patient using an electroanatomical approach with a three-dimensional mapping system. Case: A 33-year-old woman underwent catheter ablation for AVNRT. The conventional approach for ablating the atrial end of the slow pathway was unsuccessful; therefore, a second attempt was made using a three-dimensional electroanatomical mapping system. The ablation was easily performed without damaging the His bundle because of a clear understanding of the anatomical relationships. Conclusion: The electroanatomical approach using a three-dimensional mapping system can be an alternative if conventional methods prove to be technically difficult because this new approach can provide precise spatial distribution of the pathways.