Revised Cardiac Risk Index for Pre-operative Risk

Introduction

The Revised Cardiac Risk Index (RCRI) was originally called the Lee Index. The Lee Index was a 9-item risk score published in 1977 by Goldman et al. In 1999 the RCRI was published by Lee et al. as a 6-item risk score derived and validated for predicting myocardial infarction, pulmonary edema, ventricular fibrillation or primary cardiac arrest, and complete heart block.

The Revised Cardiac Risk Index (RCRI) for pre-operative risk allows the clinician in the inpatient or outpatient preoperative setting to risk-stratify patients before undergoing a procedure or surgery. However, the score is not as well validated in emergency surgery patients. RCRI can also be a tool to help patients understand their individual risk profile as a part of an informed consent conversation. When patients present with elevated risk (RCRI ≥ 1, age ≥ 65, or age 45-64 with significant cardiovascular disease), additional preoperative risk stratification is provided (e.g. serum NT-proBNP or BNP) along with post-op cardiac monitoring recommendations (e.g. EKG, troponins). The RCRI has been validated by multiple studies. A large 2010 systematic review found moderate discrimination in predicting major perioperative cardiac complications (Ford, 2010). According to Duceppe (2017), other perioperative cardiac risk scores, such as the Myocardial Infarction and Cardiac Arrest (MICA) Score and the American College of Surgeons (ACS) National Surgical Quality Improvement Program (NSQIP) Score, have only been retrospectively validates and likely underestimates the risk of myocardial ischemia.

Scoring

The Revised Cardiac Risk Index (RCRI) is intended for the following population undergoing elective non-cardiac surgery or urgent/semi-urgent (non-emergent) non-cardiac surgery:

• Patients ≥ 45 years or

• Patients 18-44 years old with significant cardiovascular disease*

*Significant cardiac disease refers to a known history of

• coronary artery disease

• peripheral artery disease

• congestive heart failure

• severe pulmonary hypertension (PHTN)

• severe obstructive intracardiac abnormality (e.g. severe aortic stenosis, severe mitral stenosis or severe hypertrophic obstructive cardiomyopathy)

*See 2014 ACC/AHA Guidelines

*Defined as death, myocardial infarction, or cardiac arrest at 30 days after noncardiac surgery (Duceppe, 2017).

Management Considerations

One or more of the following criteria have been met:

1. RCRI score ≥ 1

2. Age ≥ 65

3. Age 45-64 with significant cardiac disease

According to the 2016 CCS Perioperative Guidelines:

• Measure the patient's NT-ProBNP or BNP (if available)

  • If NT-ProBNP is ≥ 300 ng/L or BNP ≥ 92 ng/L, then order an EKG in the PACU and troponins to be measured daily for 48-72 hours 

  • If NT-ProBNP is < 300 ng/L or BNP < 92 ng/L (after risk stratification), then no routine postoperative cardiac monitoring is warranted.

• If these assays are not available, then all patients require

  • monitoring with an EKG in the PACU and

  • troponins to be measured daily for 48-72 hours

.

Lee TH, Marcantonio ER, Mangione CM, Thomas EJ, Polanczyk CA, Cook EF, Sugarbaker DJ, Donaldson MC, Poss R, Ho KK, Ludwig LE, Pedan A, Goldman L. Derivation and prospective validation of a simple index for prediction of cardiac risk of major noncardiac surgery. Circulation. 1999 Sep 7;100(10):1043-9.