What are the key steps in preoperative cardiovascular risk assessment?

Key Steps in Preoperative Cardiovascular Risk Assessment

Preoperative cardiovascular risk assessment should follow a systematic stepwise approach that prioritizes identification of high-risk conditions and stratification of patients based on clinical risk factors and surgical risk.

Step 1: Assess Urgency of Surgery

• Emergency surgeries may not allow time for comprehensive evaluation 1
• For emergencies, focus on perioperative medical management and surveillance 2

Step 2: Review Prior Cardiac Interventions and Evaluations

• If coronary revascularization within past 5 years and stable clinical status, further cardiac testing generally unnecessary 1
• If favorable coronary evaluation within past 2 years without new symptoms, repeat testing usually not needed 1

Step 3: Identify Major Clinical Predictors of Risk

Major predictors that may require delay of elective surgery include 1:

• Unstable coronary syndromes (unstable/severe angina, acute/recent MI)
• Decompensated heart failure
• Significant arrhythmias (high-grade AV block, symptomatic ventricular arrhythmias, supraventricular arrhythmias with uncontrolled rate)
• Severe valvular disease

Step 4: Assess Intermediate Clinical Risk Factors

Evaluate for presence of 1, 2:

• History of ischemic heart disease
• History of compensated/prior heart failure
• History of cerebrovascular disease
• Diabetes mellitus (particularly insulin-dependent)
• Renal insufficiency (creatinine >2.0 mg/dL)
• Uncontrolled systemic hypertension

Step 5: Evaluate Functional Capacity

• Determine if patient can achieve ≥4 METs (e.g., climb flight of stairs, walk on level ground at 6.4 km/h) 1
• Poor functional capacity (<4 METs) is associated with increased perioperative risk 3
• Consider using validated tools like Duke Activity Status Index 1

Step 6: Determine Surgery-Specific Risk

Categorize surgical risk 1:

• High-risk: Major vascular, prolonged procedures with large fluid shifts/blood loss
• Intermediate-risk: Intraperitoneal, intrathoracic, carotid, head/neck, orthopedic, prostate
• Low-risk: Endoscopic, superficial, cataract, breast procedures

Step 7: Risk Stratification and Management

Based on clinical risk factors, functional capacity, and surgical risk:

For patients with 0-1 risk factors:

• Proceed with planned surgery
• No additional cardiac testing needed 2

For patients with ≥2 risk factors undergoing intermediate/high-risk surgery:

• Consider non-invasive cardiac testing if results would change management 3
• Consider perioperative beta-blockade (starting 1 month before surgery if possible) 4
• Initiate statin therapy (ideally 30 days before surgery) 4

Common Pitfalls to Avoid

1. Overuse of preoperative testing: Stress testing rarely indicated in low-risk patients and may unnecessarily delay surgery 4

2. Inappropriate beta-blocker use: High-dose beta-blockers administered 2-4 hours before surgery increase stroke and mortality risk 3

3. Routine coronary revascularization: Does not reduce perioperative risk and should not be performed without specific indications independent of planned surgery 3

4. Ignoring age as risk factor: Advanced age (>75 years) significantly increases perioperative cardiovascular risk 3

5. Underestimating risk in vascular surgery patients: The Revised Cardiac Risk Index may underestimate risk in these patients 2

6. Neglecting troponin monitoring: For intermediate/high-risk patients undergoing high-risk surgery, check troponin preoperatively and at 24/48 hours after surgery 1

7. Discontinuing necessary medications: Maintain appropriate antiplatelet therapy unless bleeding risk is prohibitive 2

8. Overlooking functional capacity assessment: Poor functional capacity is a strong predictor of adverse outcomes 1

The 2024 AHA/ACC guidelines emphasize that this stepwise approach should guide perioperative risk stratification and management, though clinical judgment remains essential for individualized care 1.