Clinical and Electrophysiological Characteristics of Patients Developing Macroreentrant Atrial Tachyarrhythmias...

Macroreentrant atrial tachycardias (MRAT) predominate the atrial arrhythmias in patients with operated heart disease, and advances in interventional electrophysiology and catheter ablation technology have pioneered a shift in their management.

We retrospectively analyzed clinical, procedural, and outcome data from a cohort of patients who had undergone radiofrequency (RF) ablation for MRAT (utilizing high-density atrial mapping) following cardiac surgery for congenital or acquired heart disease.

Forty-one patients underwent ablation for a MRAT from 2016 to 2023. These patients had a mean age of 50.17 ± 11.71 years and had undergone cardiac surgical intervention a median of 18 years prior to first presentation with atrial tachyarrhythmia. The commonest repaired lesion was a surgically corrected atrial septal defect. None of the studied patients had a left-sided macro reentrant circuit. The patients were followed up for a median duration of 2 years following ablation. Twenty-five patients (60.9%) had CTI-dependent atrial flutter (AFl). Using a strategy of high-density activation and voltage mapping and entrainment mapping to define the tachycardia circuit, an acute success rate of 95.1% was noted. Our population continued to do well on medium-term follow-up, with 90.2% of patients tachycardia-free at 2 years. However, seven patients (17.1%) developed sinus bradycardia requiring pacing, and three patients (7.3%) developed incident atrial fibrillation.

A meticulous approach to MRAT mapping utilizing a combination of newer high-density mapping catheters with entrainment mapping yields high rates of acute (95.1%) and medium-term success (90.2%) in patients with antecedent cardiac surgery.