The American College of Cardiology and nine other cardiovascular societies issued updated Appropriate Use Criteria (AUC) for imaging in patients with stable ischemic heart disease (SIHD), which now include ratings for all imaging modalities available to clinicians.

The AUC, published online Dec. 17 in the Journal of the American College of Cardiology, include updated guidelines for calcium scoring, coronary computed tomography angiography, stress cardiac magnetic resonance and invasive coronary angiography. The criteria rate the use of imaging in 80 clinical situations as appropriate, may be appropriate and rarely appropriate.

“[T]his is the first imaging AUC document that now integrates the rating of variety of procedures ranging from the exercise ECG [echocardiogram] to the diagnostic coronary angiogram, representing the array of choices available to the medical community,” the authors wrote. They added that they did not provide cross-indication comparisons between modalities because of a lack of comparative data.

“This approach to current and future AUC documents represents an effort to produce a single AUC document on effective procedural choices for a given clinical strategy rather than procedure specific AUC documents.”

The AUC generally consider diagnostic imaging as appropriate or may be appropriate when initially assessing patients with symptoms representing ischemic equivalents, a new diagnosis of heart failure, arrhythmias and syncope. Other than exercise ECGs, however, imaging is not recommended in cases of low pre-test probability or low risk because the testing would not be beneficial.

Testing to evaluate new or worsening symptoms that manifest after previous tests was rated as appropriate or may be appropriate as was testing within three months of an abnormal prior test. Pre-operative testing was rated appropriate or may be appropriate for patients with poor functional capacity or who had intermediate or vascular surgery with at least one risk factor before an organ transplant. Exercise echocardiography was considered appropriate to clear patients for cardiac rehabilitation or if exercise were prescribed.

The only cases in which testing in asymptomatic patients was appropriate was calcium scoring and exercise testing in intermediate and high-risk patients as well as stress or imaging of the anatomy in higher-risk patients.

The panel also considered follow-up testing after a previous test, within two years of PCI and within five years of CABG rarely appropriate in the absence of new symptoms. AUC also rated pre-operative testing for patients with good functional capacity, previous tests within one year that were normal, or who had low-risk surgery as rarely appropriate.

The authors explained that while the guidelines are based on available evidence, physician discretion should also play a role in imaging decisions. “The contributors also recognize diversity in clinical opinion for particular clinical scenarios,” they wrote. “As such, the criteria can inform procedure use, but physician judgment is required for individual patient decisions.”