It is recognized, however, that a clinician might select a procedure for a patient with a moderate to high pretest likelihood of IHD to provide information for both diagnosis and risk assessment, whereas in a patient with a low likelihood of IHD, it could be sensible to select a test simply for diagnostic purposes without regard to risk assessment. By separating the conceptual approaches to ascertaining diagno- Asymptomatic (SIHD) Asymptomatic Persons Without Known IHD (CV Risk) Stable Angina or Low-Risk UA* (SIHD; PCI/CABG) Acute Coronary Syndromes (UA/NSTEMI; STEMI; PCI/CABG) Patients with Known IHD Noncardiac Chest Pain New Onset Chest Pain (SIHD; UA/NSTEMI; STEMI) Sudden Cardiac Death (VA-SCD) Noninvasive Testing *Features of low risk unstable angina: Age, 70 y Exertional pain lasting <20 min. Pain not rapidly accelerating Normal or unchanged ECG No elevation of cardiac markers Figure 1. Spectrum of IHD. Guidelines relevant to the spectrum of IHD are in parentheses. CABG indicates coronary artery bypass graft; CV, cardio- vascular; ECG, electrocardiogram; IHD, ischemic heart disease; PCI, percutaneous coronary inter- vention; SCD, sudden cardiac death; SIHD, stable ischemic heart disease; STEMI, ST-elevation myo- cardial infarction; UA, unstable angina; UA/NSTEMI, unstable angina/non ST-elevation myocardial infarction; and VA, ventricular arrhythmia. sis and prognosis, the goal of the writing committee is to promote the sensible application of appropriate testing rather than routine use of the most expensive or complex tests whether warranted or not. It is not the intent of the writing committee to promote unnecessary or duplicate testing, al- though in some patients this could be unavoidable. Additionally, this guideline addresses the approach to asymptomatic patients with SIHD that has been diagnosed solely on the basis of an abnormal screening study, rather than on the basis of clinical symptoms or events such as anginal symptoms or ACS. 