What is the operative mortality rate for Coronary Artery Bypass Grafting (CABG)?

From the Guidelines

The operative mortality rate for coronary artery bypass grafting (CABG) is generally between 1-4%, depending on the population studied. This rate can vary significantly based on several factors including patient age, comorbidities, and urgency of the procedure 1. Higher risk patients, such as those over 75 years old, those with poor left ventricular function, or patients requiring emergency surgery, may face mortality rates of 5-8% or higher. Conversely, younger patients without significant comorbidities may have mortality rates below 1%.

Key Factors Influencing Mortality Rate

• Patient age: older patients tend to have higher mortality rates
• Comorbidities: presence of conditions such as diabetes, hypertension, or chronic obstructive pulmonary disease (COPD) can increase mortality risk
• Urgency of the procedure: emergency surgeries tend to have higher mortality rates compared to elective procedures The mortality risk is typically assessed using validated scoring systems like the Society of Thoracic Surgeons (STS) risk calculator or EuroSCORE II, which incorporate multiple patient-specific variables to provide individualized risk estimates 1. These mortality figures have improved substantially over recent decades due to advances in surgical techniques, perioperative care, and patient selection. It's essential to consider that while operative mortality is a critical metric, it represents only one aspect of surgical outcomes, and long-term survival benefits often outweigh the initial procedural risk for appropriate candidates.

Long-Term Survival Benefits

• CABG can improve long-term survival and reduce the risk of myocardial infarction
• The use of arterial grafts, such as the left internal thoracic artery (LITA), can improve survival and reduce the incidence of late myocardial infarction and recurrent angina 1 In contrast to older studies, more recent data is not available in the provided evidence, however, the most recent study available 1 provides a general estimate of the operative mortality rate for CABG.

From the Research

Operative Mortality Rate for CABG

• The operative mortality rate for coronary artery bypass grafting (CABG) has been reported to be around 1.87% in a study of 34,416 patients 2.
• A study of 4310 patients undergoing isolated off-pump CABG reported a postoperative mortality rate of 0.7% 3.
• Another study found that the mortality rate for emergency CABG was 4.7%, compared to 2.6% for elective CABG 4.
• The goal of achieving an operative mortality rate of 1.0% for CABG is considered feasible in appropriately selected patients, but may only be achievable in around 60% of CABG patients without other improvements in processes of care 2.

Factors Affecting Operative Mortality Rate

• Patient risk profile, including factors such as age, sex, and comorbidities, can affect the operative mortality rate for CABG 2, 4.
• The use of off-pump CABG has been shown to improve early clinical outcomes, including operative mortality, compared to on-pump CABG 3.
• The choice of conduit for bypass grafts and target coronary selection can also affect survival and operative mortality rate 5.

Current Evidence and Recommendations

• The current evidence suggests that CABG remains the standard of care for obstructive coronary artery disease, particularly for patients with multivessel disease or diabetes 5.
• A multidisciplinary approach, including surgeons with a special interest in CABG, is recommended to optimize treatment selection and outcomes 5.
• Further study is needed to determine if an operative mortality rate of 1.0% for CABG is achievable nationwide 2.