High density mapping and catheter ablation of atrial tachycardias in adults with congenital heart disease

Aims We used a new grid-style multi-electrode mapping catheter (Advisor (TM) HD Grid, Abbott) and investigated its use for high density mapping of atrial tachycardias in adult patients with congenital heart disease. Patients and methods All patients with congenital heart disease who had mapping of atrial tachycardias using the new grid-style catheter between March 2018 and April 2019 were included. Results A total of 24 adult patients had high density mapping of atrial tachycardias using the grid-style multi-electrode catheter. Mean procedure duration was 207 +/- 72 min., mean fluoroscopy time was 7.1 +/- 7.9 min. In patients with right atrial substrates, fluoroscopy time was shorter compared to biatrial or left atrial substrates (0.9 +/- 2.2 min for right atrial substrates, n = 19 vs. 6.3 +/- 8.3 min for left atrial substrates, n = 2 and 7.5 +/- 4.3 min for biatrial substrates, n = 3, p = 0.01). A mean number of 14.814 +/- 10.140 endocardial points were collected and 2.319 +/- 1244 points were finally used to characterize the tachycardia. Procedural success was achieved in 21/24 (88%) subjects and partial success in 2/24 (8%) patients. Recurrence rate was low (12.5%). In one patient, radiofrequency ablation within the cavotricuspid isthmus resulted in occlusion of a branch of the right coronary artery. No complications related to the use of the mapping catheter itself occurred. Conclusion High density mapping of AT using the grid-style catheter showed promising results with respect to procedural and midterm outcome and fluoroscopy time. Using the grid-style catheter might offer advantages compared to other multi-electrode catheters used for high density mapping of AT in patients with CHD.