Original Contribution Comparison of exercise electrocardiogram and exercise echocardiography in intermediate-risk chest pain patients Alberto Conti, MD a, ⁎, Andrea Alesi, MD a , Giovanna Aspesi, MD a , Sofia Bigiarini, MD a , Simone Bianchi, MD a , Elena Angeli, MD a , Maurizio Zanobetti, MD b , Francesca Innocenti, MD b , Riccardo Pini, MD b , Gian Franco Gensini, MD c a Emergency Medicine and Chest Pain Clinic, Department of Critical Care Medicine and Surgery, Careggi University Hospital, Florence, Italy b Emergency Medicine, Department of Critical Care Medicine and Surgery, Careggi University Hospital, Florence, Italy c Department of Cardiology, Careggi University Hospital, Florence, Italy abstract article info Article history: Received 12 June 2014 Received in revised form 23 September 2014 Accepted 24 September 2014 Available online xxxx Background: The novel exercise computer-assisted high-frequency QRS analysis (HF/QRS) has demonstrated improved sensitivity and specificity over the conventional ST/electrocardiogram-segment analysis (ST/ECG) in the detection of myocardial ischemia. The aim of the present study was to compare the diagnostic value of the validated exercise echocardiography (ex-Echo) with the novel exercise ECG (ex-ECG) including HF/QRS and ST/ECG analysis. Methods: A prospective cohort study was conducted in the emergency department of a tertiary care teaching Hospital. Patients with chest pain (CP), normal resting ECGs, troponins, and echocardiography, labeled as “inter- mediate-risk” for adverse coronary events, underwent the novel ex-ECG and ex-Echo. An ST-segment depression of at least 2 mV or at least 1 mV when associated with CP was considered as an index of ischemia, as well as a decrease of at least 50% in HF/QRS intensity, or new wall motion abnormalities on ex-Echo. Exclusion criteria were QRS duration of at least 120 milliseconds, poor echo-acoustic window, and inability to exercise. Patients were followed up to 3 months. The end point was the composite of coronary stenoses of 50% or greater at angiography or acute coronary syndrome, revascularization, and cardiovascular death on the 3-month follow-up. Results: Of 188 patients enrolled, 18 achieved the end point. The novel ex-ECG and ex-Echo showed comparable negative predictive value (97% vs 96%; P = .930); however, sensitivity was 83% vs 61%, respectively (P = .612), and specificity was 64% vs 92%, respectively,(P = .026). The areas on receiver operating characteristic analysis were comparable (ex-ECG: 0.734 [95% confidence interval, or CI, 0.62-0.85] vs ex-Echo: 0.767 [CI, 0.63-0.91]; C statistic, P = .167). On multivariate analysis, both ex-ECG (hazard ratio, 5; CI, 1-20; P = .017) and ex-Echo (HR, 12; CI, 4-40; P b .001) were predictors of the end point. Conclusions: In intermediate-risk CP patients, the novel ex-ECG including HF/QRS added to ST/ECG analysis was a valuable diagnostic tool and might be proposed to avoid additional imaging. However, the novel test needs additional study before it can be recommended as a replacement for current techniques. © 2014 Elsevier Inc. All rights reserved. 1. Introduction The exercise echocardiography (ex-Echo), exercise stress myocardi- al perfusion imaging, and coronary computed tomography angiography (CTA) have shown higher diagnostic values over the exercise tolerance test in the diagnosis of stress-induced ischemia. Indeed, the sensitivity and specificity for coronary disease of the exercise tolerance test are reported to be up to 50% and 90%, respectively, compared with 85% and 88% of ex-Echo, 92% and 97% of exercise stress myocardial perfusion imaging, and 99% and 83% of CTA, respectively [1]. However, the exercise tolerance test is widely available, is less expensive, and avoids ionizing radiation, whereas nuclear scan, stress echocardiography, and CTA require specific expertise and time-sensitive availability. Thus, in patients with chest pain and nondiagnostic electrocardiograms (ECGs) and normal troponin levels, which tests should be used is still under debate. Because of the increasing imbalance between infinite demand and finite resources, we need to consider pretest probability and test sensitivity or specificity to the threshold approach to clinical decision making [2]. In the emergency setting, the validated exercise tolerance test is still considered the optimal first-line test for risk/assessment in intermediate-risk patients with suspected myocardial ischemia [3,4]. Recently, the automated computer-assisted analysis of high-frequency mid-QRS components during exercise (ex-HF/QRS) has been proposed for diagnostic in chest pain patients referred for exercise tolerance test. This novel electrocardiographic technique allows the detection of stress-induced ischemia by examining the high-frequency QRS American Journal of Emergency Medicine xxx (2014) xxx–xxx ⁎ Corresponding author at: Emergency Medicine and Chest Pain Clinic, Department of Critical Care Medicine and Surgery, Careggi University Hospital, Florence, Italy. E-mail addresses: xalbertoconti@gmail.com, aaaconti@hotmail.com (A. Conti). http://dx.doi.org/10.1016/j.ajem.2014.09.035 0735-6757/© 2014 Elsevier Inc. All rights reserved. Contents lists available at ScienceDirect American Journal of Emergency Medicine journal homepage: www.elsevier.com/locate/ajem Please cite this article as: Conti A, et al, Comparison of exercise electrocardiogram and exercise echocardiography in intermediate-risk chest pain patients, Am J Emerg Med (2014), http://dx.doi.org/10.1016/j.ajem.2014.09.035