Initial Diagnostic Evaluation of Stable Coronary Artery Disease: The Need for a Patient‐Centered Strategy

T he diagnosis and subsequent management of coronary artery disease (CAD) represents a major challenge to our healthcare systems, affecting millions of patients each year. Despite many years and literally thousands of publications, the optimal approach for the evaluation of stable ischemic heart disease remains unclear. Functional or stress testing to detect inducible ischemia has been the “gold standard” and remains the most common noninvasive test used to diagnose stable CAD. However, the advent of coronary computed tomography angiography (CCTA) has created a genuine debate regarding the best initial modality for the workup of stable CAD. Furthermore, simple and low-cost diagnostic options, such as ECG stress testing (GXT), should be considered, given extensive clinical experience and current pressures on healthcare resources. In this issue of JAHA, Roifman and colleagues evaluated initial testing strategies for stable CAD with anatomical versus functional stressing modality in a nonselected general population. The cohort consisted of 15 467 patients who had undergone a noninvasive test, with the end point being obstructive coronary artery disease on invasive coronary angiography. The authors demonstrated that neither stress imaging nor CCTA resulted in a higher diagnostic yield for obstructive CAD than GXT, a rather surprising result. Outcome data were also provided and did not demonstrate superior risk discrimination with cardiac imaging, as compared with GXT. The design of the current study has inherent selection biases that limit the conclusions and utility of these data. Patients had to have undergone both a noninvasive test and then invasive coronary angiography within 6 months of the index test to be included. Additionally, patients who had a noninvasive study during the preceding year were excluded. Depending on the testing modality, only 3.8% to 6.5% of patients having noninvasive testing underwent invasive angiography for the definitive diagnosis of CAD. In aggregate, only 3.3% of the initial cohort undergoing stress testing or CCTA were included in this retrospective trial. A major concern regarding this article was the use of the Framingham Risk Score rather than a determination of the pretest probability for coronary artery disease; this is critically important as Framingham Risk Score does not include an assessment of symptoms and should be used for evaluation of the 10-year risk for developing coronary heart disease. The use of the Framingham Risk Score for something other than prognosis is therefore an incorrect application of this measure. The authors do quote existing guidelines but do not stress that these guidelines offer specific scenarios for some of the recommendations; they also seem to overstate the impact of their findings. It is clear that not all patients with suspected CAD are the same and risk factors, pre-existing diagnoses, ability to exercise, the interpretability of an ECG, and the purpose of the evaluation should be considered in the selection of noninvasive testing. The European Society of Cardiology Guidelines clearly base noninvasive test selection for the initial diagnosis of CAD on the pretest likelihood of CAD and actually make a Class I recommendation for GXT in patients with an intermediate likelihood of CAD who have an interpretable ECG and can exercise. A virtually identical recommendation is made by the 2012 American College of Cardiology/American Heart Association guidelines, as supported by the appropriate use criteria. Thus, it appears that no guidelines recommend cardiac imaging procedures as the initial test in this population, although the European Society of Cardiology document does indicate that stress imaging is an initial testing option depending on local expertise. Both guidelines suggest stress imaging when the pretest likelihood is higher than intermediate or when the resting ECG is uninterpretable. It also is obvious that GXT cannot be considered the initial testing option when patients are unable The opinions expressed in this article are not necessarily those of the editors or of the American Heart Association. From the Section of Cardiology, Department of Medicine, Tulane University; Heart and Vascular Institute, Tulane University School of Medicine, New Orleans, LA. Correspondence to: Robert C. Hendel, MD, 1430 Tulane Ave, Suite 7550, New Orleans, LA 70115. E-mail: [email protected] J Am Heart Assoc. 2017;6:e006863. DOI: 10.1161/JAHA.117.006863. a 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley. This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.