A Rare Case of Permanent Junctional Reciprocating Tachycardia Ablated on the Roof of the Left Atrium

Abstract

Left-sided anteroseptal accessory pathways that course through the aortomitral fibrous continuity are some of the rarest types of accessory pathways. At this region the atrium and ventricle are separated by their greatest distance because of the intervening aortic valve. These pathways often have a long circuitous course that may involve the root and cusps of the aortic valve. Prior reports have demonstrated the feasibility of ablating these pathways along the anteroseptal mitral annulus, the left ventricular outflow tract, or in the left or noncoronary cusps of the aortic valve. We describe a case of a concealed decremental anteroseptal accessory pathway that was ablated on the roof of the left atrium remote from the mitral or aortic valve annuli. This report indicates that when an appropriate site for ablation of a left-sided anteroseptal accessory pathway is not found close to a valve annulus, these pathways may be amenable to ablation by targeting their atrial insertion site.

Ablation of Left‐Sided Accessory Pathways with Atrial Insertion Away from the Mitral Annulus Using an Electroanatomical Mapping System

“…Although it has not been systematically studied and fewer reports were found in medical literature, atrial insertions away from the MA could be the reason of ablation failure in patients with left‐sided APs . The initial report by Di Biase et al .…”

Electrophysiologic Characteristics of Ventricular Arrhythmias Arising from the Aortic Mitral Continuity—Potential Role of the Conduction System

“…Although successful ablation of arrhythmias at the AMC has been described, [1][2][3][4][5][6][7][8][9][10][11][12] the exact nature of the arrhythmogenic substrate remains unknown. 4,[13][14][15][16][17] While no myocardium has been found in this region, animal studies have shown that cells with electrophysiological properties similar to that of the atrioventricular (AV) junctional cells are present near the mitral annulus.…”

“…The aortic mitral continuity (AMC) is a fibrous structure embedded between the aortic and mitral annuli. Although successful ablations of arrhythmias at the AMC have been reported in the literature, [1][2][3][4][5][6][7][8][9][10][11][12] knowledge of the clinical, electrocardiographic (ECG), and electrophysiological characteristics of idiopathic ventricular arrhythmias (VAs) arising from this region remains limited. Furthermore, being a fibrous structure, the exact nature of the arrhythmogenic substrate remains unclear.…”

Electrophysiologic Characteristics of Ventricular Arrhythmias Arising From the Aortic Mitral Continuity – Potential Role of the Conduction System

“…Although successful ablation of arrhythmias at the AMC has been described, [1][2][3][4][5][6][7][8][9][10][11][12] the exact nature of the arrhythmogenic substrate remains unknown. 4,[13][14][15][16][17] While no myocardium has been found in this region, animal studies have shown that cells with electrophysiological properties similar to that of the atrioventricular (AV) junctional cells are present near the mitral annulus.…”

“…Although successful ablations of arrhythmias at the AMC have been reported in the literature, [1][2][3][4][5][6][7][8][9][10][11][12] knowledge of the clinical, electrocardiographic (ECG), and electrophysiological characteristics of idiopathic ventricular arrhythmias (VAs) arising from this region remains limited. Furthermore, being a fibrous structure, the exact nature of the arrhythmogenic substrate remains unclear.…”