Effectiveness of Early Invasive Therapy for Atrial Tachycardia in Adult Atrial-Baffle Survivors

Abstract

I nteratrial baffle procedures, such as Mustard or Senning operations, were the standard of care in the mid-to late 20th century for patients born with dextrotransposition of the great arteries (D-TGA). The surgical process of redirecting systemic and pulmonary venous circulation with complex baffling in the atria is a known risk factor for late atrial tachyarrhythmias.1 Newer surgical techniques, such as the atrial switch, have supplanted interatrial baffle operations.The substrate for late atrial tachyarrhythmia has historically been reported as atrial flutter or intra-atrial reentrant tachycardia (IART).1 Investigators have since shown that atrioventricular (AV) nodal reentrant tachycardia (AVNRT) and nonautomatic focal atrial tachycardia (NAFAT) are also prevalent.3,4 (Nonautomatic FAT is defined as an arrhythmia inducible with pacing maneuvers and presumably caused by microreentry or by triggered mechanisms.) Original attempts at radiofrequency ablation (RFA) in these patients were reasonably successful. 5 The increasing frequency of RFA has engendered newer transbaffle access (TBA) techniques that enable access to the pulmonary venous atrium (PVA). 6,7 The goal is to offer more lasting control of atrial arrhythmias.Our institution has experienced a notable increase in adult Mustard and Senning survivors who present with clinically significant, recurrent atrial arrhythmias. Antiarrhythmic agents are relatively ineffective and can have undesirable side effects. Using a strategy of early RFA intervention (after ≤1 trial of antiarrhythmic therapy) with atrial mapping, our team of adult and pediatric electrophysiologists studied short-and midterm RFA outcomes in adults with a prior Mustard or Senning procedure who presented at our institution over a period of one year for clinically significant arrhythmias.