Revised Cardiac Risk Index for Pre-Operative Risk
Why Use
Provides individualized risk stratification prior to undergoing surgery, which can be helpful in discussions of informed consent. Contains 6 objective, binary variables and is scored in an additive manner. In patients with elevated risk (RCRI ≥1, age ≥65, or age 45-64 with significant cardiovascular disease), this tool helps direct further preoperative risk stratification (e.g., with serum NT-proBNP or BNP) and determine appropriate cardiac monitoring post-op (e.g., EKG, troponins).
When to Use
Patients ≥45 years old (or 18-44 years old with significant cardiovascular disease) undergoing elective non-cardiac surgery or urgent/semi-urgent (non-emergent) non-cardiac surgery. Use with caution in patients undergoing emergency surgery or vascular surgery, as the score is not as well validated for the former and performance is known to be poor for the latter.
Formula
Pearls / Pitfalls
Easy to use by any involved specialty, including general internal medicine, cardiology, anesthesia, and surgery. Can be used in the inpatient or outpatient preoperative setting. Includes a limited number of risk factors, in part because the original studies did not include a sufficient number of patients for every important risk factor (e.g., it underestimates hemodynamic and cardiovascular outcomes in valvular disease). Other patient-important outcomes that are not assessed by this tool include risk of stroke, major bleeding, prolonged hospitalization, and ICU admission. While the 2017 Canadian Cardiovascular Society specified the RCRI in their preoperative cardiovascular assessment algorithm for patients undergoing elective surgery, more recent European (2022) and American (2024) guidelines no longer recommend any specific tool.
Advice
According to the 2017 CCS Perioperative Guidelines : If the RCRI is ≥1, the patient’s age is ≥65, or they are between 45-64 years old with significant cardiac disease, consider obtaining NT-proBNP or BNP. If the NT-proBNP is ≥300 ng/L or BNP is ≥92 ng/L, then an EKG should be ordered in the PACU, and troponins should be measured daily for 48-72 hours. If, after risk stratification, the NT-proBNP is <300 ng/L or BNP <92 ng/L, no routine postoperative cardiac monitoring is recommended. If these assays are not available, then patients should be monitored with an EKG in the PACU and troponin measurements daily for 48-72 hours if they meet any one of the following additional criteria: known history of coronary artery disease, cerebral vascular disease, peripheral artery disease, heart failure, severe pulmonary hypertension, or a severe obstructive intracardiac abnormality (e.g., severe aortic stenosis, severe mitral stenosis, or severe hypertrophic obstructive cardiomyopathy). The data supporting the use of NT-proBNP/BNP comes from a large 2014 meta-analysis of 18 studies with a total of 2,477 patients ( Rodseth 2014 ). This study, which was in agreement with multiple previous meta-analyses, noted that for patients with a pre-operative NT-proBNP of <300 ng/L or BNP <92 ng/L, the rate of 30-day postoperative non-fatal MI or death was 4.9% (3.9%-61%), and was 21.8% (19.0%-24.8%) in those with pre-operative NT-proBNP is ≥300 ng/L or BNP is ≥92 ng/L.
More Information
Interpretation per the original 1999 study. Values are based on a combination of derivation and validation sets. RCRI Score Approximate Risk of Major Cardiac Event (95% CI)* 0 0.5% 1 1.1% 2 5% ≥3 10% * 2024 American guidelines do not list the exact risk estimates for each score level and instead refer to an RCRI >1 as denoting elevated risk. **2017 CCS guidelines and 2022 ESC guidelines offer alternative risk levels based on RCRI score. Consider adjusting interpretation based on region.