Left atrial-coronary sinus dissociation following an attempt at radiofrequency ablation for a left lateral accessory...

Area of Science:

• Electrophysiology
• Cardiac Arrhythmia Research
• Interventional Cardiology

Background:

• Coronary sinus (CS) electrograms are crucial for localizing left lateral accessory pathways and diagnosing supraventricular tachycardias (SVTs).
• CS activation typically mirrors left atrial (LA) activation via muscle bridges, aiding in tachycardia mechanism interpretation.
• Disconnection of these muscle bridges can lead to dissociation between CS and LA activation.

Observation:

• A case of orthodromic SVT mediated by a left lateral accessory pathway is presented.
• During radiofrequency ablation, the coronary sinus became dissociated from the left atrium.
• This dissociation altered the expected electrogram patterns.

Findings:

• Dissociated coronary sinus electrograms do not accurately represent left atrial activation.
• This phenomenon can lead to misinterpretation of SVT mechanisms.
• The case highlights a potential pitfall during electrophysiological studies and ablation.

Implications:

• Understanding CS-LA dissociation is vital for accurate SVT diagnosis and successful ablation.
• Clinicians must consider the possibility of dissociation when interpreting CS electrograms.
• This finding emphasizes the need for careful assessment of electrophysiological signals during catheter ablation procedures.