Electrophysiological features and radiofrequency catheter ablation of accessory pathways associated with atrioventricular discordance

Abstract

Introduction: Although a high prevalence of the presence of an accessory pathway (AP) associated with atrioventricular (AV) discordance has been reported, a case series of its characteristics and the results of catheter ablation (CA) have not been sufficiently documented. Methods and Results:We retrospectively examined 11 consecutive patients with atrioventricular discordance who underwent CA for atrioventricular reciprocating tachycardia (AVRT) via an AP and planned cardiac surgery after CA. Orthodromic AVRTs were induced in 10 patients via AP, but no antidromic/duodromic AVRT was induced in any of the cases. A total of 13 APs were identified, and all of them were located around the anatomical tricuspid valve (TV) annulus, including two Ebsteinoid valves. The APs were predominantly located posteriorly, posterolaterally, and posteroseptally on the TV in nine patients (82%). Two patients (18%) had multiple APs or a single broad AP. Four (36%) and three (27%) patients showed twin AVNs and other supraventricular tachycardias (SVTs) except AVRT via the AP. Ten patients (91%) had acute successful CA in the first session, except for one patient with multiple APs who required the third session to eliminate all APs before the planned Fontan surgery. There were no major complications associated with CA. Seven of eight patients who underwent cardiac surgery after CA did not experience peri-/postoperative SVT.Conclusion: APs in patients with AV discordance are usually associated with the anatomical TV annulus. CA of an AP in AV discordance is highly effective and recommended to reduce the risk of SVT. The coexistence of twin AVNs and other SVTs should be considered during CA of an AP in AV discordance. K E Y W O R D S accessory pathway, atrioventricular discordance, atrioventricular tachycardia, corrected transposition of the great arteries, radiofrequency catheter ablation, supraventricular tachycardia

JCS 2022 Guideline on Management and Re-Interventional Therapy in Patients With Congenital Heart Disease Long-Term After Initial Repair

“…Patients with the Ebstein malformation, 358,359 discordant AV connection (as seen in ccTGA) and heterotaxy syndrome, are known to possess accessory pathways at a high incidence. 360, 361 The Wolffe-Parkinson-White (WPW) syndrome occurring after reparative cardiac surgery has been reported as caused by electrical junction of the atrial and ventricular tissues. 362 The details of AVNRT associated with congenital malformations are not well known.…”

Therapy of supraventricular and ventricular arrhythmias in adults with congenital heart disease—narrative review

“…Patients with congenital heart disease can also develop paroxysmal SVT due to atrioventricular nodal reentrant tachycardia (AVNRT) or atrioventricular tachycardia (AVRT) via an accessory pathway and focal atrial tachycardia (13). Accessory pathways and associated arrhythmias are most often seen in Ebstein's anomaly and congenitally corrected transposition of the great arteries (14)(15)(16)(17)(18). Twin AV-nodes are present most often in patients with congenitally corrected TGA (1,19,20) and can give rise to AVNRT in these patients.…”

Doubly unusual in double discordance: Appendage-based accessory pathway in congenitally corrected transposition

“…In ccTGA, the left-sided tricuspid valve often has features of Ebstein anomaly, and accessory pathways tend to be located on its annulus or in the septal/paraseptal region ( Table 1 ). 3 , 4 , 5 …”