Association Between Electrocardiographic Changes and Myocardial Injury or Death After Cardiac Surgery

Area of Science:

• Cardiology
• Cardiac Surgery
• Electrocardiography

Background:

• The association between myocardial injury after cardiac surgery (MICS), electrocardiogram (ECG) ischemia, and mortality remains unclear.
• This study investigates potential ischemic ECG changes following cardiac surgery and their link to 30-day mortality.

Purpose of the Study:

• To determine the association between potential ischemic ECG changes after cardiac surgery and 30-day mortality.
• To analyze the prognostic significance of various ischemic ECG patterns in the post-cardiac surgery population.

Main Methods:

• A cohort of 12,594 adult patients undergoing cardiac surgery was analyzed.
• Preoperative and postoperative ECGs (59,539 total) were reviewed for new potential ischemic changes.
• Statistical models adjusted for EuroSCORE II and analyzed mortality risk based on specific ECG findings.

Main Results:

• 72.2% of patients exhibited potential ischemic ECG changes; 2.1% died within 30 days.
• ST depression (≥ 2 mm) was linked to increased mortality (HR 2.17), while new Q waves (HR 0.57) and T-wave inversions (HR 0.58) were associated with lower mortality.
• New left bundle branch block (LBBB) increased mortality risk significantly only in patients who underwent coronary artery bypass grafting (CABG) (HR 2.78).

Conclusions:

• Potential ischemic ECG changes are frequent post-cardiac surgery but have varied associations with mortality.
• ST depression signifies a higher risk, whereas new Q waves and T-wave inversions indicate a lower risk of death.
• New LBBB is a significant mortality risk factor specifically after CABG, highlighting the need for nuanced interpretation of ECG changes.