PreambleSince 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, based on systematic methods to evaluate and classify evidence,
provide a cornerstone of quality cardiovascular care.In response to reports from the Institute of Medicine1,2
and a mandate to evaluate new knowledge and maintain relevance at the point of
care, the ACC/AHA Task Force on Clinical Practice Guidelines (Task Force)
modified its methodology.3–5 The
relationships among guidelines, data standards, appropriate use criteria, and
performance measures are addressed elsewhere.5Intended UsePractice guidelines provide recommendations applicable to patients
with or at risk of developing cardiovascular disease. The focus is on
medical practice in the United States, but guidelines developed in
collaboration with other organizations may have a broader target. Although
guidelines may be used to inform regulatory or payer decisions, the intent
is 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.
Guidelines are reviewed annually by the Task Force and are official policy
of the ACC and AHA. Each guideline is considered current until it is
updated, revised, or superseded by published addenda, statements of
clarification, focused updates, or revised full-text guidelines. To ensure
that guidelines remain current, new data are reviewed biannually to
determine whether recommendations should be modified. In general, full
revisions are posted in 5-year cycles.3–6ModernizationProcesses have evolved to support the evolution of guidelines as
“living documents” that can be dynamically updated. This
process delineates a recommendation to address a specific clinical question,
followed by concise text (ideally <250 words) and hyperlinked to
supportive evidence. This approach accommodates time constraints on busy
clinicians and facilitates easier access to recommendations via electronic
search engines and other evolving technology.Evidence ReviewWriting committee members review the literature; weigh the quality of
evidence for or against particular tests, treatments, or procedures; and
estimate expected health outcomes. In developing recommendations, the
writing committee uses evidence-based methodologies that are based on all
available data.3–7 Literature searches focus on
randomized controlled trials (RCTs) but also include registries,
nonrandomized comparative and descriptive studies, case series, cohort
studies, systematic reviews, and expert opinion. Only selected references
are cited.The Task Force recognizes the need for objective, independent
Evidence Review Committees (ERCs) that include methodologists,
epidemiologists, clinicians, and biostatisticians who systematically survey,
abstract, and assess the evidence to address syste...