Lee’s Cardiac Risk Index (Original RCRI) Calculator

Ischemic Heart Disease (history of MI/positive stress test/current angina/use of nitrates/pathological Q waves) Check if present Congestive Heart Failure (history or signs/symptoms consistent with CHF) Check if present Cerebrovascular Disease (history of stroke or TIA) Check if present Diabetes Mellitus on Insulin Check if patient uses insulin Serum Creatinine mg/dL µmol/L Threshold for RCRI point: > 2.0 mg/dL (≈ > 177 µmol/L). Lee’s Cardiac Risk Index (Original RCRI): Explanation and Clinical Context The Revised Cardiac Risk Index (RCRI) by Lee and colleagues is a simple six-variable bedside tool to estimate the risk of major perioperative cardiac complications in patients undergoing noncardiac surgery. Each predictor scores one point: high-risk surgery (intraperitoneal, intrathoracic, or suprainguinal vascular), history of ischemic heart disease, history of congestive heart failure, history of cerebrovascular disease (stroke or TIA), treatment with insulin for diabetes, and elevated preoperative serum creatinine > 2.0 mg/dL (≈ 177 µmol/L).

The sum of points classifies patients into four risk strata with observed event rates in the original cohort: Class I (0 points) ≈ 0.4%, Class II (1 point) ≈ 0.9%, Class III (2 points) ≈ 7.0%, and Class IV (≥ 3 points) ≈ 11.0% for a composite of myocardial infarction, pulmonary edema, ventricular fibrillation/cardiac arrest, or complete heart block. Clinical Significance RCRI supports preoperative risk discussion, guides the need for perioperative optimization, and informs shared decision-making about further testing or monitoring. A higher class suggests greater likelihood of perioperative cardiac events and may warrant intensifying medical therapy (e.g., guideline-directed therapy for ischemic heart disease or heart failure), adjusting anesthetic/monitoring plans, and considering surgery-site or timing modifications when appropriate.

Interpretation Notes RCRI is most accurate in noncardiac, nonemergent surgeries similar to the derivation cohort and may under- or over-estimate risk in very high-risk vascular procedures, emergent cases, or populations with contemporary preventive therapies. It should be integrated with clinical judgment, surgical urgency, functional capacity, and current perioperative guidelines. Thresholds and definitions here follow the original publication to preserve predictive characteristics of the classic score.

Reference Lee TH, Marcantonio ER, Mangione CM, et al. Derivation and prospective validation of a simple index for prediction of cardiac risk of major noncardiac surgery. Circulation.

1999;100:1043–1049.