CABG indicates coronary artery bypass graft; CAD, coronary artery disease; COPD, chronic obstructive pulmonary disease; COR, class of recommendation; EF, ejection fraction; LAD, left anterior descending; LIMA, left internal mammary artery; LOE, level of evidence; LV, left ventricular; N/A, not available; PCI, percutaneous coronary intervention; SIHD, stable ischemic heart disease; STEMI, ST-elevation myocardial infarction; STS, Society of Thoracic Surgeons; SYNTAX, Synergy between Percutaneous Coronary Intervention with TAXUS and Cardiac Surgery; TIMI, Thrombolysis In Myocardial Infarction; UA/NSTEMI, unstable angina/non ST-elevation myocardial infarction; UPLM, unprotected left main disease; and VT, ventricular tachycardia. Table 19. 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 $1 significant stenoses and unacceptable angina in whom GDMT cannot be implemented because of medication contraindications, adverse effects, or patient preferences IIa CABG C N/A IIa PCI C N/A Previous CABG with $1 significant stenoses associated with ischemia and unacceptable angina despite GDMT IIa PCI C (1021 1024) IIb CABG C (1025) 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 (980, 987 989) Viable ischemic myocardium that is perfused by coronary arteries that are not amenable to grafting IIb TMR as an adjunct to CABG B (923, 927, 929, 1026, No anatomic or physiological criteria for revascularization III: Harm CABG C N/A 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 available; PCI, percutaneous coronary intervention; SYNTAX, Synergy between Percutaneous Coronary Intervention with TAXUS and Cardiac Surgery; and TMR, transmyocardial revascularization. 