The location of the touch up sites in the SVCI
Miyazaki et al. reported that conduction gaps were located on the anterolateral wall of the SVCI in the majority of cases (15). Our study also revealed that touch up ablation was needed in the anterior and lateral areas. The median value of the AI in the anterior and lateral areas was relatively lower than that in the posterior and septal areas. The ablation of the anterior or lateral area had a potential risk of sinus node or phrenic nerve complications. As a result of the fact that the operators worried about these complications, the AI value may have been lower than that of the other areas. The lower AI value in the anterior and lateral areas resulted in a higher incidence of touch up ablation in those areas.