The Task Force strives to avoid bias by selecting experts from a broad array of back- grounds representing different geographic regions, sexes, ethnicities, intellectual perspectives/biases, and scopes of clinical practice, and by inviting organizations and pro- fessional societies with related interests and expertise to participate as partners or collaborators. Related Issues For additional information pertaining to the methodology for grading evidence, assessment of bene t and harm, shared decision making between the patient and clini- cian, structure of evidence tables and summaries, stan- dardized terminology for articulating recommendations, organizational involvement, peer review, and policies for periodic assessment and updating of guideline docu- ments, we encourage readers to consult the ACC/AHA guideline methodology manual (1). The recommendations in this focused update represent the of cial policy of the ACC and AHA until superseded by published addenda, statements of clari cation, focused up- dates, or revised full-text guidelines. To ensure that guide- lines remain current, new data are reviewed biannually to determine whether recommendations should be modi ed. In general, full revisions are posted in 5-year cycles (1). Jonathan L. Halperin, MD, FACC, FAHA Chair, ACC/AHA Task Force on Clinical Practice Guidelines The scope of this focused update is limited to consider- ations relevant to multivessel percutaneous coronary intervention (PCI) and thrombus aspiration in patients with ST-elevation myocardial infarction (STEMI) under- going primary PCI. 1.1. Methodology and Evidence Review Clinical trials presented at the major cardiology organi- zations 2013 to 2015 annual scienti c meetings and other selected reports published in a peer-reviewed format through August 2015 were reviewed by the 2011 PCI and 2013 STEMI GWCs and the Task Force to identify trials and other key data that might affect guideline rec- ommendations. 