R-on-T Phenomenon Causing Cardiac Arrest in a Post-coronary Artery Bypass Graft (CABG) Patient

Area of Science:

• Cardiology
• Cardiac Surgery
• Electrophysiology

Background:

• Temporary epicardial pacing wires are frequently used post-coronary artery bypass graft (CABG) surgery to prevent and manage cardiac arrhythmias like bradycardia and atrioventricular (AV) block.
• These wires are typically placed on the right atrium and ventricle and can also aid in sequential atrioventricular pacing to improve cardiac output in patients with reduced ejection fraction.

Observation:

• Certain patient risk factors, including advanced age, valvular surgery, poor left ventricular function, diabetes, and pre-existing arrhythmias, increase the likelihood of developing life-threatening arrhythmias post-CABG.
• While generally considered a life-saving measure, there are rare instances where temporary epicardial pacing itself can precipitate adverse cardiac events.

Findings:

• This report details a specific case where temporary epicardial pacing wires, intended to prevent arrhythmias, instead triggered ventricular arrhythmias.
• The complication arose due to improper sensing by the epicardial pacing wires, leading to an unintended pro-arrhythmic effect.

Implications:

• This case underscores the importance of vigilant monitoring and appropriate programming of temporary epicardial pacing systems in the post-CABG setting.
• Recognizing and managing complications related to improper sensing is crucial for patient safety and optimizing outcomes after cardiac surgery.
• Further investigation into sensing abnormalities with temporary epicardial pacing may be warranted to refine clinical practice and prevent rare but serious adverse events.