The entire membership of both GWCs voted on the re- vised recommendations and text. The latter group was composed of experts representing cardiovascular med- icine, interventional cardiology, electrophysiology, heart failure, cardiac surgery, emergency medicine, internal medicine, cardiac rehabilitation, nursing, and pharmacy. The GWC included representatives from the ACC, AHA, American College of Physicians, American College of Emergency Physicians, and So- ciety for Cardiovascular Angiography and Interven- tions (SCAI). 1.3. Review and Approval This document was reviewed predominantly by the prior reviewers from the respective 2011 and 2013 guidelines. These included 8 official reviewers jointly nominated by the ACC and AHA, 4 official/organiza- tional reviewers nominated by SCAI, and 25 individual content reviewers. Reviewers RWI information was distributed to the GWC and is published in this docu- ment (Appendix 3). This document was approved for publication by the governing bodies of the ACC, the AHA, and the SCAI and was endorsed by the Latin American Society of Interventional Cardiology. 2. CULPRIT ARTERY ONLY VERSUS MULTIVESSEL PCI (See Section 5.2.2.2 of 2011 PCI guideline and Sec- tion 4.1.1 of 2013 STEMI guideline for additional rec- ommendations.) Approximately 50% of patients with STEMI have multivessel disease. [25,26] PCI options for patients with STEMI and multivessel disease include: 1) culprit artery only primary PCI, with PCI of nonculprit arteries only for spontaneous ischemia or intermediate- or high-risk findings on predischarge noninvasive test- ing; 2) multivessel PCI at the time of primary PCI; or 3) culprit artery only primary PCI followed by staged PCI of nonculprit arteries. Observational studies, randomized controlled trials (RCTs), and meta-analyses comparing culprit artery only PCI with multivessel PCI have reported conflicting results, [11,12,14 24,27,28] likely because of differing inclu- sion criteria, study protocols, timing of multivessel PCI, statistical heterogeneity, and variable endpoints (Data Supplement). 