What does an RCRI (Revised Cardiac Risk Index) score of 2 indicate in terms of cardiac risk for non-cardiac surgery?

RCRI Score of 2: Moderate Cardiac Risk Classification

An RCRI score of 2 indicates moderate cardiac risk for non-cardiac surgery, with a predicted major adverse cardiovascular event (MACE) rate of approximately 6.7-7.4%, requiring functional capacity assessment to guide further preoperative evaluation and management decisions. 1, 2

Risk Stratification

The Revised Cardiac Risk Index stratifies patients into distinct risk categories based on the number of risk factors present 1:

• RCRI 0-1: Low risk (<1% MACE rate) 1, 3
• RCRI 2: Moderate risk (6.7-7.4% MACE rate) 4, 2
• RCRI ≥3: High risk (≥14.4% MACE rate) 2

With an RCRI score of 2, patients fall into the moderate-risk category, which is significantly elevated compared to low-risk patients but lower than high-risk patients. 1, 4

Clinical Management Algorithm for RCRI Score of 2

Step 1: Assess Functional Capacity

The critical next step is determining functional capacity, measured in metabolic equivalents (METs) or using the Duke Activity Status Index. 5, 1

• If functional capacity ≥4 METs (excellent): Proceed directly to surgery without further cardiac testing 5, 1
• If functional capacity <4 METs (poor) or unknown: Consider whether further testing would change management 5, 1

Activities requiring ≥4 METs include moderate cycling, climbing hills, singles tennis, and jogging, while activities <4 METs include slow ballroom dancing and walking at 2-3 mph 5

Step 2: Consider Additional Testing (If Functional Capacity Poor/Unknown)

Pharmacological stress testing (dobutamine stress echocardiogram or myocardial perfusion imaging) is reasonable only if results will change management decisions. 1

• A preoperative 12-lead ECG is reasonable for patients with known coronary heart disease or significant structural heart disease 1
• Routine preoperative coronary angiography is not recommended 1
• Biomarker assessment (BNP/NT-proBNP) may be reasonable for additional risk stratification 1

Step 3: Surgery-Specific Risk Consideration

For vascular surgery patients with RCRI score of 2, testing should only be considered if it will change management. 5

For intermediate-risk non-vascular surgery, there are insufficient data to determine the best strategy, but proceeding with tight heart rate control with beta blockade is reasonable. 5

Perioperative Medical Management

Beta Blockers

• Continue beta blockers in patients already taking them chronically (Class I recommendation) 1, 3
• For patients not on beta blockers, it may be reasonable to begin them before surgery, preferably more than 1 day before surgery to assess safety and tolerability 1
• Manage beta blockers after surgery based on clinical circumstances, with attention to hypotension, bradycardia, or bleeding 1

Other Medications

• Continue statins in patients currently taking them (Class I recommendation) 1, 3
• Continuation of ACE inhibitors or ARBs is reasonable perioperatively (Class IIa recommendation) 1
• Consider guideline-directed medical therapy for long-term cardiovascular risk reduction 1

Common Pitfalls and Caveats

Emergency surgery increases cardiac risk regardless of RCRI score. 6

The RCRI has moderate discriminative ability but may have suboptimal accuracy in certain clinical settings. 7

For thoracic surgery patients, the Thoracic Revised Cardiac Risk Index (ThRCRI) may be more appropriate, though some studies question its accuracy. 1

History of ischemic heart disease is the strongest independent predictor of perioperative events among the six RCRI variables. 4

Age >70 years, poor general medical condition, emergency surgery, and left bundle branch block on ECG are significantly associated with perioperative events beyond the RCRI score. 4

Key RCRI Risk Factors

The six independent predictors that comprise the RCRI include 1, 6:

• History of ischemic heart disease
• History of congestive heart failure
• History of cerebrovascular disease
• High-risk surgery
• Preoperative insulin treatment for diabetes mellitus
• Preoperative kidney dysfunction (creatinine >2 mg/dL or GFR <30 mL/min)

Note that a GFR <30 mL/min is a better predictor than creatinine >176.8 mmol/L alone. 2