What is the Revised Cardiac Risk Index?

The RCRI (Lee Criteria), published by Lee et al. in 1999 (Circulation), is a 6-predictor clinical scoring system that stratifies perioperative cardiac risk for major non-cardiac surgery into Classes I through IV.

What are the canonical RCRI / Lee classes?

Score 0 corresponds to Class I (Low Risk); Score 1 to Class II (Low Risk); Score 2 to Class III (Intermediate Risk); and Scores 3 to 6 to Class IV (High Risk).

What surgeries does the RCRI apply to?

It applies to adult non-cardiac surgeries (orthopedic, abdominal, vascular, thoracic, urological, etc.). It is not derived or validated for cardiac surgery or minor ambulatory procedures (e.g., superficial dermatologic or cataract procedures).

What qualifies as high-risk surgery under RCRI?

High-risk surgical procedures include suprainguinal vascular, intrathoracic, or intraperitoneal procedures.

What is the 2024 AHA/ACC guideline threshold?

The 2024 AHA/ACC perioperative guideline traditionally treats RCRI > 1 (scores 2 through 6) as an elevated calculated risk threshold. Scores of 0 or 1 are below this traditional elevated threshold.

Why are fixed complication percentages not hardcoded?

In the original 1999 Lee study, complication rates differed between derivation (0.4%, 0.9%, 6.6%, 11.0%) and validation cohorts (0.5%, 1.3%, 4.0%, 9.0%), and modern surgical cohorts show broad variability depending on biomarker surveillance and endpoint definitions. Presenting the score and Lee class avoids false precision.

Revised Cardiac Risk Index

Add one point for each of the six validated Lee criteria to determine the 0–6 RCRI score and Lee Class (I–IV) before non-cardiac surgery.

Six Clinical Criteria

1 pt each

Select each validated predictor present preoperatively.

High-Risk Surgery Suprainguinal vascular, intraperitoneal, or intrathoracic procedure

History of Ischemic Heart Disease Prior MI, positive stress test, angina, nitrate therapy, or pathologic Q waves

History of Congestive Heart Failure Prior pulmonary edema, PND, bilateral rales, S3 gallop, or clinical heart failure

History of Cerebrovascular Disease Prior transient ischemic attack (TIA) or stroke

Preoperative Insulin Therapy Diabetes mellitus currently treated with preoperative insulin

Preoperative Creatinine > 2.0 mg/dL Baseline serum creatinine > 2.0 mg/dL (> 177 µmol/L)

Perioperative Risk Assessment

RCRI Score (0–6)

Class I

Low Risk

Score Progression (0–6) Below traditional elevated threshold

Score 0 Score >1 (Elevated) Score 6

0 of 6 predictors selected

Canonical RCRI (Lee) Stratification AHA/ACC Framework

Class	Score	Risk Tier	2024 AHA/ACC Threshold
Class I	0	Low	Below traditional elevated threshold
Class II	1	Low	Below traditional elevated threshold
Class III	2	Intermediate	Elevated calculated risk marker
Class IV	3–6	High	Elevated calculated risk marker

Clinical Guidance & Limitations

RCRI Class I (Score 0). Below the traditional elevated-risk cutoff. Integrate with symptoms, functional capacity, surgical urgency, and clinician judgment.

Primary composite endpoint: Myocardial infarction, pulmonary edema, ventricular fibrillation/primary cardiac arrest, and complete heart block (Lee et al. 1999).

Cohort variability: Event rates differ significantly across historic cohorts (0.4%–11.0% in Lee 1999) and contemporary surgical registries; RCRI provides risk stratification rather than an absolute single-patient probability.

Scope: Decision-support tool for adult non-cardiac surgery. It does not replace individualized multidisciplinary assessment or mandate surgical postponement.

Summary

The Revised Cardiac Risk Index (RCRI), derived and validated by Lee et al. in 1999, sums six equally weighted clinical predictors before major non-cardiac surgery to stratify patients into Classes I through IV. Its original composite cardiac outcome included myocardial infarction, pulmonary edema, ventricular fibrillation or primary cardiac arrest, and complete heart block. The 2024 AHA/ACC guideline traditionally identifies an RCRI score greater than 1 as an elevated calculated risk marker. The score provides structured decision support and must be integrated with functional capacity, surgical urgency, and patient factors.

How it works

Review the six independent Lee criteria and select each that applies to the patient.
The calculator sums one point per criterion for a total score of 0 to 6.
Scores map directly to canonical Lee Classes: Class I (0), Class II (1), Class III (2), and Class IV (3–6).
Scores above 1 (>1) reach the traditional 2024 AHA/ACC threshold for elevated calculated perioperative risk.
Click Copy Clinical Summary to generate a formatted perioperative note for the health record.
Event rates vary by surgical cohort and cardiac endpoint; use score and class in clinical context rather than a single fixed percentage.

Use cases

Preoperative cardiac risk stratification before elective non-cardiac surgery.
Determining whether a patient meets the traditional RCRI > 1 elevated calculated risk threshold.
Standardizing perioperative documentation in EHR pre-anesthetic and surgical consult notes.
Facilitating multidisciplinary discussion among surgeons, anesthesiologists, and cardiologists.
Bedside risk assessment in preoperative holding areas and surgical pre-assessment clinics.

Frequently Asked Questions

Last updated: 2026-09-30 · Reviewed by Nham Vu