Incidentally Induced Atrial Fibrillation During Programmed Electrical Stimulation in Patients With Depressed Left...

Area of Science:

• Cardiology
• Electrophysiology
• Clinical Research

Background:

• Patients with left ventricular systolic dysfunction post-myocardial infarction (MI) are at risk for arrhythmias.
• Programmed electrical stimulation (PES) is used to assess arrhythmia risk.
• The clinical significance of incidentally induced atrial fibrillation (AF) during PES in this population is not well-defined.

Purpose of the Study:

• To investigate the long-term clinical implications of incidentally induced AF during PES.
• To determine if incidental AF during PES predicts future AF, other arrhythmias, or major cardiovascular events (MACE) in post-MI patients with reduced ejection fraction.

Main Methods:

• The study included 231 patients from the CARISMA study with LVEF ≤40% and no prior AF history.
• Patients underwent PES 6 weeks post-MI and received an implantable cardiac monitor (ICM) for 2-year continuous monitoring.
• Incidental AF during PES was recorded and analyzed in relation to long-term outcomes.

Main Results:

• Of 231 patients, 61 (26%) developed AF within 2 years; 10 had incidental AF during PES.
• Incidental AF during PES was not associated with a significantly increased risk of long-term AF (HR 1.6 [0.9-3.0], p=0.14).
• No significant differences were observed in the risk of bradyarrhythmia, ventricular arrhythmias, or MACE between patients with and without incidental AF.

Conclusions:

• Incidentally induced AF during PES in post-MI patients with reduced LVEF is not significantly associated with increased long-term risk of AF.
• This finding suggests that incidental AF during PES may not be a strong predictor of future cardiac arrhythmias or MACE in this specific patient group.