CABG or PCI should not be performed with the primary or sole intent to improve survival in patients with SIHD with 1 or more coronary stenoses that are Table 3. Revascularization to Improve Symptoms With Significant Anatomic (>50% Left Main or >70% Non Left Main CAD) or Physiological (FFR <0.80) Coronary Artery Stenoses Clinical Setting COR LOE References 1 significant stenoses amenable to revascularization and unacceptable angina despite GDMT I CABG I PCI 1 significant stenoses and unacceptable angina in whom GDMT cannot be implemented because of medication contraindications, adverse effects, or patient preferences IIa CABG IIa PCI C N/A Previous CABG with 1 significant stenoses associated with ischemia and unacceptable angina despite GDMT IIb CABG C 381 Complex 3-vessel CAD (eg, SYNTAX score 22) with or without involvement of the proximal LAD artery and a good candidate for CABG IIa CABG preferred over PCI B 320, 343, 359 361 Viable ischemic myocardium that is perfused by coronary arteries that are not amenable to grafting IIb TMR as an adjunct to CABG B 397 401 No anatomic or physiologic criteria for revascularization III: Harm CABG III: Harm PCI C N/A CABG indicates coronary artery bypass graft; CAD, coronary artery disease; COR, class of recommendation; FFR, fractional flow reserve; GDMT, guideline-directed medical therapy; LOE, level of evidence; N/A, not applicable; PCI, percutaneous coronary intervention; SYNTAX, Synergy between Percutaneous Coronary Intervention with TAXUS and Cardiac Surgery; and TMR, transmyocardial laser revascularization. not anatomically or functionally significant (eg, <70% diameter non left main coronary artery stenosis, frac- tional flow reserve >0.80, no or only mild ischemia on noninvasive testing), involve only the left circumflex or right coronary artery, or subtend only a small area of viable myocardium.318,341,348,349,382 386 (Level of Evi- dence: B) 3.3. Revascularization to Improve Symptoms: Recommendations Class I 1. 