Coronary computed tomographic angiography and exercise electrocardiography: a great match or unequal partners?The opinions expressed in this article are not necessarily those of the Editors of the European Heart Journal or of the European Society of Cardiology.

Abstract

Coronary computed tomographic angiography (CCTA) is emerging as a powerful non-invasive tool in the diagnosis of coronary artery disease (CAD). However, there is concern that CCTA is being used indiscriminately without sufficient examination of its added value vis-a-vis more established forms of non-invasive testing.1 With an ever-growing armament of non-invasive tests for the diagnosis and evaluation of CAD, cardiologists must consider the following questions in weighing up the implementation of a new diagnostic modality in the routine clinical setting. Is testing necessary for the diagnosis of CAD in a particular patient group? Will testing guide management decisions and identify patients who may benefit from coronary revascularization? Will the benefits of testing outweigh its potential risks? The study by Mollet et al. 2 provides important insights into the relationship between the findings of CCTA and conventional treadmill exercise electrocardiography (ECG), but also raises important issues regarding the role of both tests in the diagnosis of CAD. The authors examined, in 62 patients with typical angina pectoris, the diagnostic value of exercise ECG and 16-slice multidetector CCTA, alone and in combination, to predict ≥50% diameter stenoses detected on invasive, selective coronary angiography (SCA) in any coronary artery branch with a calibre of ≥2 mm. Exercise ECG data from 53 patients and CCTA data from 61 patients were included in the analyses. The sensitivity of exercise ECG was 78%, specificity was 67%, and positive and negative predictive values were 89 and 47%, respectively. The sensitivity of CCTA was 100%, specificity was 87%, and positive and negative predictive values were 96 and 100%, respectively. In an analysis based on Bayesian principles, an abnormal CCTA increased the post-test probability of significant CAD after a positive exercise ECG from 89 to 99% and after a negative exercise ECG from 58 to 91%. A normal CCTA … *Corresponding author. E-mail address : gerber.thomas{at}mayo.edu