Concealed Accessory Pathways with a Single Ventricular and Two Discrete Atrial Insertion Sites.

Area of Science:

• Electrophysiology
• Cardiology

Background:

• Atrioventricular reciprocating tachycardia (AVRT) involving concealed accessory pathways is a frequent clinical finding.
• Some patients exhibit multiple accessory pathways with distinct atrial and ventricular connections.

Observation:

• This study details three cases of AVRT with concealed pathways, each featuring a single ventricular insertion site and two separate atrial insertion sites.
• Case one demonstrated two discrete atrial insertion sites, with successful ablation of the Kent potential terminating retrograde conduction in both pathways.
• Case two involved supraventricular tachycardia (SVT) with alternating atrial activation patterns, successfully treated by ablating two distinct atrial insertion sites.
• Case three identified retrograde decremental conduction through two atrial insertion sites, with persistent SVT after ablating the first site, requiring ablation of the second for noninducibility.

Findings:

• Concealed retrograde accessory pathways can possess multiple, discrete atrial insertion sites sharing a common ventricular insertion point.
• Successful ablation strategies target either the common ventricular insertion site or the individual discrete atrial insertion sites.

Implications:

• Understanding multiple accessory pathway anatomy is crucial for effective ablation in complex AVRT cases.
• Targeted ablation of discrete atrial insertion sites offers a successful treatment for AVRT with multiple pathways.