PREAMBLE Since 1980, the American College of Cardiology (ACC) and American Heart Association (AHA) have translated scientific evidence into clinical practice guidelines with recommendations to improve cardiovascular health. These guidelines, which are based on systematic meth- ods to evaluate and classify evidence, provide a founda- tion for the delivery of quality cardiovascular care. The ACC and AHA sponsor the development and publica- tion of clinical practice guidelines without commercial support, and members volunteer their time to the writ- ing and review efforts. CLINICAL STATEMENTS AND GUIDELINES Clinical practice guidelines provide recommenda- tions applicable to patients with or at risk of developing cardiovascular disease (CVD). The focus is on medical practice in the United States, but these guidelines are relevant to patients throughout the world. Although guidelines may be used to inform regulatory or payer decisions, the goals are to improve quality of care and align with patients interests. Guidelines are intended to define practices meeting the needs of patients in most but not all circumstances and should not replace clinical judgment. Recommendations for guideline-directed manage- ment and therapy, which encompasses clinical evalua- tion, diagnostic testing, and both pharmacological and procedural treatments, are effective only when adopted by both practitioners and patients. Adherence to rec- ommendations can be enhanced by shared decision- making between clinicians and patients, with patient engagement in selecting interventions on the basis of individual values, preferences, and associated condi- tions and comorbidities. The ACC/AHA Task Force on Clinical Practice Guide- lines strives to ensure that the guideline writing com- mittee includes requisite expertise and is representative of the broader medical community by selecting experts from a broad array of backgrounds, representing dif- ferent geographic regions, sexes, races, ethnicities, intellectual perspectives/biases, and scopes of clinical practice. 