Should a patient with a history of old myocardial infarction (MI) as indicated by electrocardiogram (EKG) findings be cleared for surgery?

Preoperative Clearance for Surgery with Old MI on EKG

A patient with an old myocardial infarction on EKG can generally be cleared for surgery, but this requires systematic risk stratification based on current cardiac status, functional capacity, and type of surgery—not simply the presence of Q waves on the ECG. 1

The EKG Finding Itself Is Not a Contraindication

• The presence of pathological Q waves indicating old MI is a documented risk factor but does not automatically preclude surgery. 1
• Q waves on preoperative ECG were associated with increased risk of major cardiac complications in one large cohort (4,135 patients), where 17% had pathological Q waves. 1
• However, a contradictory study of 513 elderly patients (≥70 years) found that ECG abnormalities—including old MI patterns—were not predictive of postoperative cardiac complications when controlling for clinical comorbidities. 2
• The key distinction: ECG abnormalities are common (75% prevalence in elderly surgical patients) but nonspecific—clinical risk factors matter more than the ECG alone. 2

Mandatory Risk Stratification Algorithm

Step 1: Assess for Active Cardiac Conditions (Absolute Priority)

Do NOT clear if any of the following are present: 1

• Decompensated heart failure (dyspnea, rales, jugular venous distension, pulmonary edema) 1
• Unstable angina or recent MI (within 30 days) 1
• Significant arrhythmias (ventricular tachycardia, symptomatic bradycardia, new high-grade AV block) 1
• Severe valvular disease (symptomatic aortic stenosis or mitral regurgitation) 1

Step 2: Identify Clinical Risk Factors

Count the number of Revised Cardiac Risk Index (RCRI) factors present: 1

• History of ischemic heart disease (including old MI on ECG—this patient has 1 point)
• History of heart failure 1
• History of cerebrovascular disease 1
• Diabetes mellitus requiring insulin 1
• Chronic kidney disease (creatinine >2 mg/dL) 1
• High-risk surgery (intraperitoneal, intrathoracic, or suprainguinal vascular) 1

Step 3: Assess Functional Capacity

Can the patient achieve ≥4 METs without cardiac symptoms? 1

• Examples of 4 METs: climb 2 flights of stairs, walk up a hill, run a short distance, do heavy housework 1
• If functional capacity is ≥4 METs and no active cardiac conditions exist, proceed to surgery regardless of RCRI score. 1
• If functional capacity is <4 METs or unknown, proceed to Step 4. 1

Step 4: Surgery-Specific Risk Assessment

Low-risk surgery (<1% cardiac event rate): Proceed without further testing 1

• Examples: cataract surgery, breast surgery, ambulatory procedures 1

Intermediate-risk surgery (1-5% cardiac event rate): 1

• If 1-2 RCRI factors: Proceed to surgery with perioperative beta-blocker consideration 1
• If ≥3 RCRI factors: Consider noninvasive stress testing if it will change management 1

High-risk surgery (>5% cardiac event rate—vascular surgery): 1

• If ≥1 RCRI factor and poor functional capacity: Consider stress testing or coronary angiography if revascularization is feasible 1

Critical Timing Considerations

• An ECG within 30 days of surgery is adequate for stable patients. 1
• If the old MI is truly remote (>6 months) and the patient is asymptomatic with preserved functional capacity, the timing of the infarct itself is less relevant than current cardiac status. 1
• Do NOT delay surgery for routine stress testing in patients with good functional capacity (≥4 METs), even with multiple risk factors. 1

Common Pitfalls to Avoid

• Do not deny surgery based solely on Q waves without assessing current symptoms, functional capacity, and comorbidities. 2
• Do not order "routine" preoperative stress tests—they should only be obtained if results will change management (e.g., lead to revascularization before surgery). 1
• The ASA Task Force found that routine ECGs led to management changes in only 9.1% of abnormal cases, emphasizing that indicated testing based on clinical risk is superior to age-based or routine screening. 1
• Recognize that ECG abnormalities in elderly patients are prevalent (75%) but have limited predictive value compared to clinical history of heart failure or high ASA physical status. 2

Documentation Requirements

At minimum, document: 1

• Focused cardiovascular history (prior MI, heart failure symptoms, angina, functional capacity) 1
• Focused physical exam (vital signs, heart sounds, lung exam for rales, peripheral edema) 1
• Current medications (especially beta-blockers, antiplatelet agents, anticoagulants) 1
• RCRI score and functional capacity assessment 1

In summary: Clear the patient if they have no active cardiac conditions, reasonable functional capacity (≥4 METs), and the surgery risk is proportionate to their cardiac risk profile. The old MI on ECG is one data point in a comprehensive assessment, not an absolute contraindication. 1, 2