For more on AHA statements and guidelines development, visit http://my.americanheart.org/statements and select the Policies and Development link. Permissions: Multiple copies, modification, alteration, enhancement, and/or distribution of this document are not permitted without the express permission of the American Heart Association. Instructions for obtaining permission are located at http://www.heart.org/HEARTORG/General/ Copyright-Permission-Guidelines_UCM_300404_Article.jsp. A link to the Copyright Permissions Request Form appears on the right side of the page. 2012 by the American College of Cardiology Foundation and the American Heart Association, Inc. Circulation is available at http://circ.ahajournals.org DOI: 10.1161/CIR.0b013e318277d6a0 ACCF/AHA TASK FORCE MEMBERS Jeffrey L. Anderson, MD, FACC, FAHA, Chair; Jonathan L. Halperin, MD, FACC, FAHA, Chair-Elect; Alice K. Jacobs, MD, FACC, FAHA, Immediate Past Chair 2009 2011 ; Sidney C. Smith, Jr, MD, FACC, FAHA, Past Chair 2006 2008 ; Cynthia D. Adams, MSN, APRN-BC, FAHA ; Nancy M. Albert, PhD, CCNS, CCRN, FAHA; Ralph G. Brindis, MD, MPH, MACC; Christopher E. Buller, MD, FACC ; Mark A. Creager, MD, FACC, FAHA; David DeMets, PhD; Steven M. Ettinger, MD, FACC ; Robert A. Guyton, MD, FACC; Judith S. Hochman, MD, FACC, FAHA; Sharon Ann Hunt, MD, FACC, FAHA ; Richard J. Kovacs, MD, FACC, FAHA; Frederick G. Kushner, MD, FACC, FAHA ; Bruce W. Lytle, MD, FACC, FAHA ; Rick A. Nishimura, MD, FACC, FAHA ; E. Magnus Ohman, MD, FACC; Richard L. Page, MD, FACC, FAHA ; Barbara Riegel, DNSc, RN, FAHA ; William G. Stevenson, MD, FACC, FAHA; Lynn G. Tarkington, RN ; Clyde W. Yancy, MD, FACC, FAHA Table of Contents Preamble e357 1. Introduction e359 1.1. Methodology and Evidence Overview e359 1.2. Organization of the Writing Committee e360 1.3. Document Review and Approval e360 1.4. Scope of the Guideline e360 1.5. General Approach and Overlap With Other Guidelines or Statements e362 1.6. Magnitude of the Problem e363 1.7. 