# What is the RCRI score?

Counts the six factors of the Revised Cardiac Risk Index (Lee 1999) and shows the risk class and the rate of major cardiac complications that the original study found after noncardiac surgery.

- Page: https://www.acalculator.org/health/rcri-calculator
- JSON spec: https://www.acalculator.org/health/rcri-calculator.json
- Version: 26ddbc58f99b

## Default answer

Example with the default inputs (High-risk surgery No, Ischemic heart disease No, Heart failure No, Stroke or TIA No, Diabetes treated with insulin No, Creatinine over 2 mg/dL No): The RCRI score is 0 (Class I); the original study found major cardiac complications in 0.4% of such patients.

## Inputs

| Key | Label | Description |
| --- | --- | --- |
| surgery | High-risk surgery | Intraperitoneal, intrathoracic, or suprainguinal vascular surgery. |
| ihd | Ischemic heart disease | A past heart attack, a positive exercise test, current chest pain from the heart, nitrate use, or Q waves on the ECG. |
| chf | Heart failure | A history of heart failure, pulmonary edema, a third heart sound, or signs of fluid in the lungs. |
| cvd | Stroke or TIA | A past stroke or transient ischemic attack (TIA). |
| insulin | Diabetes treated with insulin | Diabetes treated with insulin before the surgery. |
| creatinine | Creatinine over 2 mg/dL | Preoperative serum creatinine over 2.0 mg/dL (177 µmol/L). |

## Outputs

| Key | Label | Description |
| --- | --- | --- |
| score | RCRI score | How many of the six factors apply, 0 to 6. |
| riskClass | Risk class | Lee class I (0), II (1), III (2), or IV (3 or more). |
| rate | Complication rate in the study | Rate of major cardiac complications (heart attack, pulmonary edema, ventricular fibrillation or cardiac arrest, complete heart block) in the Lee 1999 validation cohort for this class. |

## Method

RCRI = the number of the six Lee factors that apply; class I (0), II (1), III (2), IV (3 or more).

## Assumptions

- For adults having elective noncardiac surgery, as in the Lee 1999 study.
- Each factor counts 1 point. The rate is the one Lee and others found in their validation cohort for the class, not a personal prediction.

## Worked examples

1. surgery = yes, ihd = no, chf = no, cvd = no, insulin = no, creatinine = no gives score = 1, riskClass = Class II, rate = 0.9%. Source: Lee et al., Circulation 1999: 1 factor is class II, 0.9% major cardiac complications in the validation cohort.
2. surgery = no, ihd = no, chf = no, cvd = no, insulin = no, creatinine = no gives score = 0, riskClass = Class I, rate = 0.4%. Source: Lee et al. 1999: 0 factors is class I, 0.4% in the validation cohort.
3. surgery = yes, ihd = yes, chf = no, cvd = no, insulin = no, creatinine = no gives score = 2, riskClass = Class III, rate = 6.6%. Source: Lee et al. 1999: 2 factors is class III, 6.6% in the validation cohort.
4. surgery = yes, ihd = yes, chf = yes, cvd = yes, insulin = yes, creatinine = yes gives score = 6, riskClass = Class IV, rate = 11%. Source: Lee et al. 1999: 3 or more factors is class IV, 11% in the validation cohort.

## FAQ

### What is the RCRI?

The Revised Cardiac Risk Index (RCRI), also called the Lee index, estimates the risk of a major heart complication after noncardiac surgery. Lee and others published it in 1999 from 4,315 patients aged 50 or older having elective major surgery. It counts six factors, one point each.

### What counts as a major cardiac complication?

In the Lee study: a heart attack, fluid in the lungs from the heart (pulmonary edema), ventricular fibrillation or cardiac arrest, or complete heart block, during the hospital stay after surgery.

### What do the classes mean?

Class I is 0 factors, class II is 1, class III is 2, and class IV is 3 or more. In the study group used to check the index, the complication rates were 0.4%, 0.9%, 6.6%, and 11%. Later studies found different rates in other groups, so the numbers are a guide, not a personal prediction.

### What is high-risk surgery in the RCRI?

Surgery inside the abdomen (intraperitoneal), inside the chest (intrathoracic), or on the large blood vessels above the groin (suprainguinal vascular).

### How do guidelines use the RCRI?

The 2024 AHA/ACC perioperative guideline lists the RCRI as one of several tools to estimate risk before surgery. It is one part of an assessment that also looks at how well a person can exercise and at the type of surgery.

## Sources

- 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(10):1043-1049. https://doi.org/10.1161/01.CIR.100.10.1043
- Thompson A, Fleischmann KE, Smilowitz NR, et al. 2024 AHA/ACC/ACS/ASNC/HRS/SCA/SCCT/SCMR/SVM guideline for perioperative cardiovascular management for noncardiac surgery. Circulation. 2024;150(19):e351-e442. https://doi.org/10.1161/CIR.0000000000001285