How is the Revised Cardiac Risk Index (RCRI) calculation used to assess cardiac risk in patients undergoing non-cardiac surgery?

From the Guidelines

The Revised Cardiac Risk Index (RCRI) is a widely used and validated clinical tool to assess perioperative cardiac risk in patients undergoing non-cardiac surgery, and it should be calculated by assigning one point for each of six independent risk factors: high-risk surgery, history of ischemic heart disease, history of congestive heart failure, history of cerebrovascular disease, preoperative insulin treatment for diabetes, and preoperative serum creatinine >2.0 mg/dL. The RCRI is used to stratify patients into risk categories, which helps clinicians make informed decisions about perioperative management, including whether additional cardiac testing is warranted, if surgery should be delayed for cardiac optimization, or if more intensive perioperative monitoring is needed 1.

Key Components of the RCRI

• High-risk surgery (intraperitoneal, intrathoracic, or suprainguinal vascular procedures)
• History of ischemic heart disease
• History of congestive heart failure
• History of cerebrovascular disease
• Preoperative insulin treatment for diabetes
• Preoperative serum creatinine >2.0 mg/dL

Risk Stratification

The RCRI stratifies patients into risk categories based on the number of risk factors present:

• Class I (0 points) with low risk of major cardiac complications
• Class II (1 point) with moderate risk
• Class III (2 points) with higher risk
• Class IV (≥3 points) with high risk

Clinical Application

The RCRI is particularly valuable because it uses readily available clinical information and provides a simple, objective assessment that can guide resource allocation and risk mitigation strategies 1. For immediate implementation, clinicians should systematically review each patient's history for these six factors before non-cardiac surgery, calculate the score, and adjust perioperative care plans according to the risk category.

Perioperative Management

The RCRI can help clinicians determine the need for:

• Additional cardiac testing
• Delaying surgery for cardiac optimization
• More intensive perioperative monitoring
• Other risk mitigation strategies to reduce the risk of major cardiac complications in patients undergoing non-cardiac surgery.

From the Research

RCRI Calculation

The Revised Cardiac Risk Index (RCRI) is a widely used model for predicting cardiac events after noncardiac surgery. The calculation of RCRI involves identifying six independent predictors of cardiac complications:

• High-risk type of surgery
• History of ischemic heart disease
• History of congestive heart failure
• History of cerebrovascular disease
• Preoperative treatment with insulin
• Preoperative serum creatinine >2.0 mg/dL

Predicting Cardiac Risk

The RCRI predicts cardiac risk by assigning points to each of these predictors. The rates of major cardiac complication with 0,1,2, or ≥3 of these factors are:

• 0 factors: 0.5% risk of major cardiac complication
• 1 factor: 1.3% risk of major cardiac complication
• 2 factors: 4% risk of major cardiac complication
• ≥3 factors: 9% risk of major cardiac complication 2

Limitations of RCRI

While the RCRI is a useful tool for predicting cardiac risk, it has some limitations. For example, it may underestimate cardiac complications in certain patient populations, such as those undergoing vascular surgery 3. Additionally, the RCRI alone is not sufficient to guide postoperative cardiac monitoring, as many patients without RCRI risk factors may still experience cardiac complications 4.

Alternative Risk Prediction Models

There are alternative risk prediction models that may be more accurate than the RCRI in certain situations. For example, the Vascular Study Group of New England Cardiac Risk Index (VSG-CRI) has been shown to more accurately predict cardiac complications in vascular surgery patients 3. Other models, such as the CtRCRI, may also be useful for predicting long-term cardiovascular outcomes 5.

Clinical Applications

The RCRI can be used in clinical practice to identify patients at higher risk for cardiac complications and to guide further risk stratification and management strategies. For example, patients with a high RCRI score may require more intensive cardiac monitoring and treatment, while those with a low score may be able to undergo surgery with minimal cardiac risk 6, 2.