About the Revised Cardiac Risk Index Calculator
The Revised Cardiac Risk Index (RCRI), also called the Lee index, estimates the risk of a major cardiac complication — myocardial infarction, pulmonary oedema, ventricular fibrillation or primary cardiac arrest, or complete heart block — after major noncardiac surgery. It was derived and prospectively validated by Lee and colleagues in 4,315 patients aged 50 or over having elective major noncardiac operations at a Boston teaching hospital (Circulation, 1999).
Six independent predictors each score one point: high-risk surgery (intraperitoneal, intrathoracic or suprainguinal vascular), a history of ischaemic heart disease, a history of congestive heart failure, a history of cerebrovascular disease, preoperative insulin treatment, and preoperative serum creatinine above 2.0 mg/dL (177 µmol/L). This calculator adds the points, assigns the RCRI class and shows the complication rates reported in the original derivation and validation cohorts.
The RCRI is a pre-operative risk stratification tool used by anaesthetists, surgeons, physicians and students. Guidelines from the ACC/AHA and others use it to separate low-risk patients (score 0–1) from those who may need further assessment. It does not by itself determine whether to test, treat or cancel surgery.
With the default inputs, the rcri score is 1 / 6. Change any value above to recalculate instantly.
How to use the revised cardiac risk index calculator
- 1Decide whether the planned operation is high risk (intraperitoneal, intrathoracic or suprainguinal vascular).
- 2Tick any history of ischaemic heart disease, heart failure or stroke/TIA.
- 3Tick insulin treatment and a creatinine above 2.0 mg/dL if present.
- 4Read the RCRI score, class and the published complication rates.
- 5Use the result alongside functional capacity and the urgency of surgery.
Formula and method
Each of the six predictors identified by multivariable analysis in the derivation cohort scores one point. Patients are grouped by the number of factors: Class I (0), Class II (1), Class III (2) and Class IV (3 or more).
Lee et al. reported major cardiac complication rates of 0.5%, 1.3%, 4% and 9% for 0, 1, 2 and ≥ 3 factors in the derivation cohort (2,893 patients), and 0.4%, 0.9%, 7% and 11% in the validation cohort (1,422 patients). The population was adults aged 50 or older undergoing elective, non-urgent major noncardiac surgery; rates in emergency surgery or other settings can differ.
- IHD
- History of ischaemic heart disease
- CHF
- History of congestive heart failure
- CVD
- History of cerebrovascular disease
Worked examples
Bowel resection, otherwise well
Intraperitoneal surgery is the only factor, giving 1 point (Class II). Lee et al. observed major cardiac complications in 0.9% of such patients in the validation cohort.
Aortic surgery with prior MI and insulin-treated diabetes
High-risk surgery, ischaemic heart disease and insulin treatment give 3 points — Class IV, with an 11% complication rate in the validation cohort.
Knee replacement in a patient with heart failure and CKD
Joint replacement is not high-risk surgery, but heart failure and creatinine above 2.0 mg/dL give 2 points (Class III, about 7% in the validation cohort).
Frequently asked questions
What counts as high-risk surgery in the RCRI?+
Intraperitoneal (abdominal cavity), intrathoracic (chest cavity) and suprainguinal vascular procedures, such as aortic aneurysm repair. Orthopaedic, peripheral vascular below the groin and superficial operations do not score.
What is a low RCRI score?+
A score of 0 or 1 is generally considered low risk, with a major cardiac complication rate of about 1% or less in the original study. Two or more factors indicate elevated risk.
Which complications does the RCRI predict?+
Major cardiac complications during the hospital stay: myocardial infarction, pulmonary oedema, ventricular fibrillation or primary cardiac arrest, and complete heart block.
Does the RCRI apply to emergency surgery?+
It was derived in patients aged 50 or more undergoing elective major noncardiac surgery. Emergency surgery carries higher risk than the RCRI suggests, and later studies show it underestimates risk in some groups, such as vascular surgery patients.
What is the creatinine threshold in µmol/L?+
The original threshold is a serum creatinine above 2.0 mg/dL, which is about 177 µmol/L.
For healthcare professionals and education only. This calculator implements a published formula or score but is not a diagnosis and does not replace clinical judgment. Verify inputs and results against the original source before using them in patient care.