Aims: The purpose of this study was to evaluate a retrograde approach for radiofrequency (RF) ablation of ectopic atrial tachycardias (EATs) with an early atrial activation at the His site.
Methods and results: This study included 12 patients with EAT. During tachycardia, earliest atrial activation was recorded at the His site at a standard catheter setting. Activation mapping was performed in the right atrium and along the mitral annulus and at the aortic root after retrograde insertion of the ablation catheter over the ascending aorta. In five patients, earliest atrial activation was recorded at the mitral annulus (in two patients at the superior-lateral annulus and in three patients at the inferior-medial annulus). In four of these patients, EAT could be successfully treated by RF ablation through the retrograde approach, whereas in one patient, a transseptal puncture was performed in order to achieve a stable catheter position. In seven patients, RF ablation at the non-coronary aortic sinus eliminated the tachycardia. During a follow-up period of 14 +/- 8 months, there was no tachycardia recurrence.
Conclusion: In patients with EATs and early atrial activation at the His site, tachycardia may arise in the non-coronary aortic sinus or from the mitral annulus. Radiofrequency energy ablation can be performed through a retrograde approach in the majority of these patients and is safe and effective in eliminating this type of tachycardia.