Is an inferior infarct on electrocardiogram (EKG) a contraindication to surgery?

Inferior Infarct on EKG is Not an Absolute Contraindication to Surgery

An inferior infarct on EKG alone is not an absolute contraindication to surgery, but timing since the infarct, patient symptoms, and hemodynamic stability must be carefully evaluated to determine perioperative risk.

Risk Assessment Framework

Major Risk Factors (Contraindications to Elective Surgery)

• Unstable coronary syndromes, including recent MI (particularly within 6 months), represent major risk predictors that may warrant postponing or canceling elective noncardiac surgery 1
• Decompensated heart failure, significant arrhythmias, or hemodynamically compromising ventricular arrhythmias associated with the inferior infarct would be contraindications to elective surgery 1
• Active ischemia with recurrent chest pain or dynamic ST-segment changes would necessitate addressing the cardiac issue before proceeding with surgery 1

Timing Considerations

• Recent inferior MI (especially within 4-6 weeks) significantly increases perioperative risk and may warrant postponing elective surgery 1
• For patients with evidence of previous inferior MI but no active symptoms, the timing since infarct is critical - risk decreases substantially after 6 months post-MI 1
• Emergency surgery may still proceed despite inferior infarct if the surgical indication outweighs cardiac risk, but with intensified perioperative monitoring 1

Evaluation Process for Patients with Inferior Infarct on EKG

Step 1: Determine if the Infarct is Recent or Old

• Obtain history to determine timing of the infarct 1
• Compare with previous ECGs if available to determine if this is a new finding 1
• Consider cardiac biomarkers (troponin) to rule out recent/acute damage 1

Step 2: Assess Functional Capacity

• Patients with excellent functional capacity (>10 METs) can generally proceed to surgery despite evidence of previous inferior infarct 1
• Poor functional capacity (<4 METs) in a patient with inferior infarct warrants further evaluation 1

Step 3: Consider Additional Risk Factors

• Presence of right ventricular involvement with inferior MI increases risk 1
• Diabetes mellitus, renal insufficiency, or other comorbidities in addition to the inferior infarct increase perioperative risk 1
• Hemodynamic instability associated with the inferior infarct is a major risk factor 1

Step 4: Determine Need for Further Testing

• If the inferior infarct is old (>6 months), patient is asymptomatic, and has good functional capacity, no further testing is needed before proceeding with surgery 1, 2
• For patients with poor functional capacity or unknown timing of infarct, stress testing may be appropriate 1
• Pharmacological stress testing (DSE or MPI) is reasonable for patients with elevated risk and poor functional capacity if it will change management 1

Special Considerations

Type of Surgery

• Low-risk procedures (endoscopic, superficial, cataract, breast surgery) can generally proceed despite inferior infarct on EKG 1, 2
• High-risk procedures (vascular, prolonged operations with large fluid shifts) require more careful evaluation in patients with inferior infarct 1

Management During Surgery

• Patients with previous inferior infarct should have continuous ECG monitoring during and after surgery 1
• Serial postoperative ECGs are recommended, especially in the first 48 hours after surgery 1
• Postoperative troponin monitoring may be valuable in patients with previous inferior infarct 1

Common Pitfalls to Avoid

• Don't assume all Q waves in inferior leads represent active ischemia - some may be old and stable 3, 4
• Don't overlook right ventricular involvement in inferior infarcts, which increases perioperative risk 1, 5
• Avoid routine coronary revascularization before noncardiac surgery exclusively to reduce perioperative cardiac events 1
• Don't rely solely on ECG findings - clinical correlation is essential 6

Conclusion for Clinical Practice

• The presence of an inferior infarct on EKG requires careful evaluation but is not an absolute contraindication to surgery
• Risk stratification should consider timing of infarct, symptoms, functional capacity, and type of surgery
• For stable patients with old inferior infarcts and good functional capacity, surgery can generally proceed with appropriate monitoring