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This document from the American Society of Nuclear Cardiology represents an updated consensus statement on the evidence base of stress myocardial perfusion imaging (MPI), emphasizing new developments in single-photon emission tomography (SPECT) and positron emission tomography (PET) in the clinical evaluation of women presenting with symptoms of stable ischemic heart disease (SIHD). The clinical evaluation of symptomatic women is challenging due to their varying clinical presentation, clinical risk factor burden, high degree of comorbidity, and increased risk of major ischemic heart disease events. Evidence is substantial that both SPECT and PET MPI effectively risk stratify women with SIHD. The addition of coronary flow reserve (CFR) with PET improves risk detection, including for women with nonobstructive coronary artery disease and coronary microvascular dysfunction. With the advent of PET with computed tomography (CT), multiparametric imaging approaches may enable integration of MPI and CFR with CT visualization of anatomical atherosclerotic plaque to uniquely identify at-risk women. Radiation dose-reduction strategies, including the use of ultra-low-dose protocols involving stress-only imaging, solid-state detector SPECT, and PET, should be uniformly applied whenever possible to all women undergoing MPI. Appropriate candidate selection for stress MPI and for post-MPI indications for guideline-directed medical therapy and/or invasive coronary angiography are discussed in this statement. The critical need for randomized and comparative trial data in female patients is also emphasized.

The evaluation of patients with suspected stable ischemic heart disease is among the most common diagnostic evaluations with nearly 20 million imaging and exercise stress tests performed annually in the United States. Over the past decade, there has been an evolution in imaging research with an ever-increasing focus on larger registries and randomized trials comparing the effectiveness of varying diagnostic algorithms. The current review highlights recent randomized trial evidence with a particular focus comparing the effectiveness of cardiac imaging procedures within the stable ischemic heart disease evaluation for coronary artery disease detection, angina, and other quality of life measures, and major clinical outcomes. Also highlighted are secondary analyses from these trials on the economic findings related to comparative cost differences across diagnostic testing strategies.

BACKGROUND: Individuals referred for stress testing to identify coronary artery disease may have nonobstructive atherosclerosis, which is not detected by stress tests. Identification of increased risk despite a negative stress test could inform prevention efforts. Abnormal ankle-brachial index (ABI) is associated with increased cardiovascular risk. HYPOTHESIS: Routine ABI testing in the stress laboratory will identify unrecognized peripheral arterial disease in some patients. METHODS: Participants referred for stress testing without known history of atherosclerotic disease underwent ABI testing (n = 451). Ankle-brachial index was assessed via simultaneous arm and leg pressure using standard measurement, automated blood-pressure cuffs at rest. Ankle-brachial index was measured after exercise in 296 patients and 30 healthy controls. Abnormal postexercise ABI was defined as a >20% drop in ABI or fall in ankle pressure by >30 mm Hg. RESULTS: Overall, 2.0% of participants had resting ABI /=1.40, and 5.5% had borderline ABI. No patient with abnormal or borderline ABI had an abnormal stress test. Participants who met peripheral arterial disease screening criteria (age >/=65 or 50-64 with diabetes or smoking) tended toward greater frequency of low ABI (2.9% vs 1.0%; P = 0.06) and were more likely to have borderline ABI (0.91 to 0.99; 7.8% vs 2.9%; P = 0.006). Postexercise ABI was abnormal in 29.4% of patients and 30.0% of controls (P not significant). CONCLUSIONS: Ankle-brachial index screening at rest just before stress testing detected low ABI in 2.0% of participants, all of whom had negative stress tests.

The exercise ECG is an integral part within the evaluation algorithm for diagnosis and risk stratification of patients with stable ischaemic heart disease (SIHD). There is evidence, both older and new, that the exercise ECG can be an effective and cost-efficient option for patients capable of performing at maximal levels of exercise with suitable resting ECG findings. In this review, we will highlight the major dilemmas in interpreting suspected coronary artery disease symptoms in women and identify optimal strategies for employing exercise ECG as a first-line diagnostic test in the SIHD evaluation algorithm. We will highlight current evidence as well as recent guideline statements on this subject. TRIAL REGISTRATION NUMBER: NCT01471522; Pre-results.

Background: Since the first version of the Appropriate Use Criteria (AUC) in Radionuclide Imaging was published in 2005, the utilization of these criteria as a means to guide test selection has exponentially increased but barriers have limited full implementation. Concurrent health care utilization management has included AUC as a guide to reimbursement coverage. In 2012, we performed a survey of primary care and cardiology specialists on AUC knowledge and utilization practices for myocardial perfusion imaging (MPI). Methods: A total of 148 clinicians (49 referring clinicians, 99 nuclear cardiac imaging specialists) participated in the scripted surveys completed by telephone or online. The scope included questions covering a range of topics to serve as a "Needs Assessment" in the field of MPI. Interviewees were questioned on their personal knowledge, experience, and practice using current AUC, their perception of colleague knowledge base and referral pattern. Both current and perceived optimal practice patterns were evaluated. Results: Compared to non-imaging referrers, cardiac imaging specialists were more likely to use AUC in practice (85.7% vs 66.7%, P = .038). Using a grading score of low-high (scores: 1-5), referring clinicians reported less knowledge of the AUC when compared to imaging specialists. By comparison, few referring clinicians (23.5%) perceived the need for improved AUC knowledge. Comparatively, imaging specialists nearly unanimously supported that referring clinicians required marked improvement in AUC knowledge (P<.0001). Referring clinicians had a self-reported knowledge gap in knowledge of SPECT and PET imaging when compared to imaging specialists (P<.0001). For example, only 60% of referring clinicians reported adequate knowledge with regards to Tc-99m SPECT as compared to 99% of imaging specialists (P<.0001). Importantly, when in doubt regarding a test indication, nearly 60% of referring clinicians reported that they refer the patient to a test. Conclusion: Sizeable gaps in knowledge exist among referring clinicians with regards to the AUC that impact daily decision-making and the effectiveness of referral patterns. Targeted educational programs are needed to improve knowledge deficiencies and to guide every day test utilization patterns of referring clinicians using MPI

The lack of standardized reporting of the magnitude of ischemia on noninvasive imaging contributes to variability in translating the severity of ischemia across stress imaging modalities. We identified the risk of coronary artery disease (CAD) death or myocardial infarction (MI) associated with >/=10% ischemic myocardium on stress nuclear imaging as the risk threshold for stress echocardiography and cardiac magnetic resonance. A narrative review revealed that >/=10% ischemic myocardium on stress nuclear imaging was associated with a median rate of CAD death or MI of 4.9%/year (interquartile range: 3.75% to 5.3%). For stress echocardiography, >/=3 newly dysfunctional segments portend a median rate of CAD death or MI of 4.5%/year (interquartile range: 3.8% to 5.9%). Although imprecisely delineated, moderate-severe ischemia on cardiac magnetic resonance may be indicated by >/=4 of 32 stress perfusion defects or >/=3 dobutamine-induced dysfunctional segments. Risk-based thresholds can define equivalent amounts of ischemia across the stress imaging modalities, which will help to translate a common understanding of patient risk on which to guide subsequent management decisions.