Revised Cardiac Risk Index (Lee Index)
Estimate perioperative major cardiac complication risk for adults undergoing non-cardiac surgery. Select all factors that apply.
What is the Lee risk calculator?
The Lee risk calculator is based on the Revised Cardiac Risk Index (RCRI), a widely used bedside tool for estimating perioperative cardiac risk before non-cardiac surgery. It is simple, fast, and clinically practical because it uses six predictors that are easy to obtain in preoperative evaluation.
Each positive predictor adds one point. The total score helps stratify risk for major cardiac complications such as myocardial infarction, pulmonary edema, ventricular fibrillation, complete heart block, and cardiac arrest.
RCRI predictors used in this calculator
- High-risk surgery
- History of ischemic heart disease
- History of congestive heart failure
- History of cerebrovascular disease (stroke/TIA)
- Diabetes requiring insulin
- Preoperative creatinine > 2.0 mg/dL (177 µmol/L)
How to interpret your score
Traditional Lee RCRI estimates
- 0 points (Class I): ~0.4% risk
- 1 point (Class II): ~0.9% risk
- 2 points (Class III): ~6.6% risk
- 3+ points (Class IV): ~11% risk
Some modern cohorts report higher absolute rates than the original study. For this reason, treat the output as a structured estimate, not a final decision by itself.
When this tool is useful
The Lee index is most helpful in pre-op visits when you need a rapid first-pass assessment to guide additional evaluation or perioperative optimization. It can support decisions around:
- Need for closer perioperative monitoring
- Discussion of risks/benefits with the patient
- Planning postoperative level of care
- Whether further cardiac workup may be appropriate
Important limitations
It does not replace clinical judgment
Risk depends on more than six variables. Functional status, urgency of surgery, frailty, active symptoms, and procedure-specific factors remain essential.
Not designed for every scenario
The RCRI was designed for non-cardiac surgery in adults. It is not a universal rule for pediatric cases, emergency contexts where data are incomplete, or highly specialized populations.
Absolute percentages vary by institution and era
Population characteristics and perioperative practices have changed over time. Use local outcomes data, specialty guidance, and shared decision-making whenever possible.
Practical pre-op checklist (beyond the score)
- Review active cardiac symptoms (chest pain, dyspnea, syncope)
- Assess functional capacity and exercise tolerance
- Optimize blood pressure, glucose, and heart failure status
- Confirm medication plans (beta-blockers, statins, anticoagulation, antiplatelets)
- Coordinate anesthesia and surgical teams for risk mitigation
Bottom line
The Lee risk calculator is a high-value screening tool: quick, validated, and clinically familiar. Use it to structure perioperative conversations and risk planning, but always combine it with full patient context and current guideline-based care.