ECG and Atrial Appendage Doppler Discordance Is Common in Patients Undergoing Cardiac Surgery: Prospective Study

Area of Science:

• Cardiology
• Cardiac Surgery
• Electrophysiology

Background:

• Patients with atrial fibrillation (AF) face elevated thromboembolism risk, even with apparent sinus rhythm, due to potential asymptomatic AF episodes.
• Atrial mechanical discordance, where the left atrium (LA) is in sinus rhythm and the left atrial appendage (LAA) is in AF, may contribute to this risk.

Purpose of the Study:

• To determine the frequency of discordance between electrocardiogram (ECG) rhythm and LAA/right atrial appendage (RAA) Doppler ejection phenotype (transesophageal echocardiography [TEE]).
• To assess this discordance in patients undergoing cardiac surgery.

Main Methods:

• 124 patients undergoing coronary artery bypass graft (CABG) or valve surgery were prospectively studied.
• Intraoperative ECG and TEE were performed before cardiopulmonary bypass.
• ECG and TEE LAA/RAA Doppler spectra were independently classified as sinus rhythm or AF.

Main Results:

• Of 107 patients without a prior AF history, 39 (36%) showed ECG/atrial appendage Doppler discordance.
• Specifically, 12% had ECG/LAA discordance and 33% had ECG/RAA discordance.
• No significant differences in age, gender, or comorbidities were found between concordant and discordant groups.

Conclusions:

• A substantial minority of cardiac surgery patients without a history of AF exhibit ECG/atrial appendage Doppler discordance.
• This discordance may heighten the risk of thromboembolism in patients not on anticoagulation.
• Clinical parameters do not reliably identify patients at increased risk for this discordance.