Diagnostic Criteria for Ischemic Heart Disease

Initial Clinical Assessment

The American College of Physicians recommends that all patients with chest pain must undergo detailed history and physical examination before any testing to assess the probability of IHD, which determines the entire diagnostic pathway and prevents unnecessary testing in low-risk patients or delayed diagnosis in high-risk patients 1
Immediately categorize patients presenting with acute angina as stable versus unstable; unstable angina patients require further categorization into high, moderate, or low risk 1
Obtain a resting ECG in all patients without an obvious noncardiac cause of chest pain for initial risk assessment 2

The American Heart Association recommends standard exercise ECG as the initial diagnostic test of choice for patients with intermediate pretest probability of IHD who have an interpretable ECG and at least moderate physical functioning, which represents the highest quality evidence (strong recommendation, high-quality evidence) 3
Exercise stress with radionuclide myocardial perfusion imaging or echocardiography should be used for patients with intermediate to high pretest probability of IHD who have an uninterpretable ECG but can exercise adequately 3
Pharmacologic stress with radionuclide myocardial perfusion imaging or echocardiography is recommended for patients with intermediate to high pretest probability of IHD who cannot achieve at least moderate physical functioning or have disabling comorbidity 4

Assess left ventricular function using Doppler echocardiography in patients with known or suspected IHD who have prior myocardial infarction, pathologic Q waves on ECG, symptoms or signs suggestive of heart failure, complex ventricular arrhythmias, or undiagnosed heart murmur 4
Conversely, do not routinely assess left ventricular function with any imaging modality in patients with normal ECG, no history of MI, no heart failure symptoms, and no complex arrhythmias 4

Never use pharmacologic stress imaging as the initial test in patients who can exercise and have an interpretable ECG, even if you think imaging will provide "better" information—this is explicitly contraindicated 1
Avoid routine imaging for left ventricular function assessment in low-risk patients with normal ECG and no concerning features 5

When stress ECG results are equivocal, proceed to stress imaging with either radionuclide myocardial perfusion imaging or stress echocardiography rather than repeating standard exercise ECG 6

All diagnostic and therapeutic decisions must involve shared decision-making with the patient, explaining risks, benefits, and costs of testing options, which is particularly important when choosing between imaging modalities or deciding whether to proceed with invasive testing based on noninvasive results 1