• congenital heart disease;
  • atrial tachycardia;
  • catheter ablation;
  • computed tomography

Introduction: Ablation of atrial tachycardia (AT) occurring late after cardiac surgery for congenital heart disease can be challenging due to the complexity of the arrhythmogenic substrate.

Methods and Results: We performed an ablation procedure in a Fontan patient with an AT using a new approach combining 3D electroanatomical mapping with multislice computed tomography (MSCT). This technique visualizes the position of the catheter in relation to the endocardium, thereby improving delineation of scar tissue. The AT had a focal origin located between areas of scar tissue and was successfully ablated at the earliest activated site.

Conclusion: Ablation of complex arrhythmias can be facilitated by fusion of electroanatomical map and MSCT.