Revascularization recommendations in this section are based predominantly on studies of patients with symptomatic SIHD and should be interpreted in this context. As discussed later in this section, recommendations on the type of revascularization are, in general, applicable to patients with UA/NSTEMI. In some cases (eg, unprotected left main CAD), specific recommendations are made for patients with UA/NSTEMI or STEMI. Historically, most studies of revascularization have been based on and reported according to angiographic criteria. Most studies have defined a significant stenosis as $70% diameter narrowing; therefore, for revascularization decisions and recommendations in this section, a significant stenosis has been defined as $70% diameter narrowing ($50% for left main CAD). Physiological criteria, such as an assessment of FFR, have been used in deciding when revascularization is indicated. Thus, for recommendations about revascularization in this section, coronary stenoses with FFR #0.80 can also be considered to be significant. As noted, the revascularization recommendations have been formulated to address issues related to 1) improved survival and/or 2) improved symptoms. When one method of revascularization is preferred over the other for improved survival, this consideration, in general, takes precedence over improved symptoms. When options for revascularization are discussed with the patient, he or she should understand when the procedure is being performed in an attempt to improve symptoms, survival, or both. Although some results from the SYNTAX (Synergy be- tween Percutaneous Coronary Intervention with TAXUS and Cardiac Surgery) study are best characterized as subgroup analyses and hypothesis generating, SYNTAX nonetheless represents the latest and most comprehensive comparison of PCI and CABG.949,950 Therefore, the results of SYNTAX have been considered appropriately when formulating our revascularization recommendations. 