What are the criteria for deciding between Coronary Artery Bypass Grafting (CABG) and Percutaneous Coronary Intervention (PCI) in patients with coronary artery disease?

Deciding Between CABG vs PCI for Coronary Artery Disease

CABG is superior to PCI for improving survival in patients with complex multivessel coronary artery disease (SYNTAX score >22), left main disease with high complexity (SYNTAX score ≥33), or diabetes with multivessel disease. 1

Anatomical Considerations

Left Main Disease

• For unprotected left main coronary artery disease (LMCAD):
  • CABG is recommended as first-line therapy for patients with high SYNTAX score (≥33) 1
  • PCI is recommended for low SYNTAX score (0-22) due to non-inferior survival and lower invasiveness 1
  • PCI should be considered for intermediate SYNTAX score (23-32) if complete revascularization can be achieved 1
  • PCI is contraindicated in patients with unfavorable anatomy who are good surgical candidates 1

Three-Vessel Disease

• CABG is recommended for patients with 3-vessel disease, particularly with:
  • Complex coronary anatomy (SYNTAX score >22) 1
  • Diabetes mellitus 1, 2
  • Involvement of proximal LAD artery 1
• PCI may be considered in 3-vessel disease with:
  • Low SYNTAX score (≤22) 1, 3
  • High surgical risk or inoperable patients 1
  • Left ventricular ejection fraction ≤35% when complete revascularization can be achieved 1

Two-Vessel Disease

• CABG is recommended if proximal LAD artery is involved 1
• CABG is reasonable with extensive ischemia (>20% perfusion defect) or when vessels supply large areas of viable myocardium 1
• PCI is recommended for two-vessel disease without proximal LAD involvement 1

Single-Vessel Disease

• CABG with LIMA graft is reasonable for isolated proximal LAD disease with evidence of extensive ischemia 1
• PCI is recommended for single-vessel disease without proximal LAD involvement 1
• Neither CABG nor PCI should be performed for non-significant stenoses (<70% diameter) or those with minimal ischemia 1

Clinical Factors

Diabetes Mellitus

• CABG is strongly preferred over PCI in diabetic patients with multivessel disease 1, 2
• Long-term data (up to 14 years) shows CABG provides:
  • Lower mortality (49.6% vs 57.6%) 2
  • Reduced myocardial infarction (15.6% vs 28.1%) 2
  • Less repeat revascularization (7.7% vs 26.9%) 2

Left Ventricular Dysfunction

• CABG is reasonable for patients with:
  • Mild-moderate LV dysfunction (EF 35-50%) and multivessel disease 1
  • Severe LV dysfunction (EF <35%) even without viable myocardium 1
• PCI should be considered in patients with LV dysfunction who are at high surgical risk 1

Symptom Relief

• Both CABG and PCI are beneficial for symptom relief in patients with significant stenoses and unacceptable angina despite medical therapy 1
• For complex 3-vessel disease, CABG is preferred over PCI for symptom improvement 1

Risk Assessment Tools

• Heart Team approach is recommended for all patients with complex CAD 1
• SYNTAX score calculation is recommended to guide decision-making 1
  • Low: 0-22
  • Intermediate: 23-32
  • High: ≥33
• STS score should be calculated to assess surgical risk 1

Outcomes Comparison

Mortality

• CABG provides significant reduction in long-term mortality compared to PCI in multivessel disease (RR 0.73) 4
• The mortality benefit is most pronounced in:
  • Complex 3-vessel disease 3
  • Diabetic patients 2
  • Left main disease with high SYNTAX score 1

Major Adverse Events

• CABG advantages:
  • Lower rates of myocardial infarction (RR 0.58) 4
  • Significantly less repeat revascularization (RR 0.29) 4, 3
• PCI advantages:
  • Trend toward fewer strokes (though not statistically significant in most studies) 4
  • Less invasive procedure with shorter recovery time 1

Common Pitfalls and Caveats

• Avoid using PCI for complex left main disease (SYNTAX ≥33) in good surgical candidates 1
• Don't perform revascularization (either CABG or PCI) for non-significant stenoses (<70%) or minimal ischemia 1
• Remember that CABG provides greater benefit in diabetic patients, even with less complex anatomy 2
• Consider that repeat revascularization rates are consistently higher with PCI across all patient subgroups 4, 3
• The benefits of CABG over PCI increase with longer follow-up periods, particularly in diabetic patients 2