Marc Dewey, MD
Coronary computed tomographic (CT) angiography and magnetic resonance (MR) angiography are both capable of providing noninvasive images of the coronary arteries (1-4) (Fig 1). Nevertheless, MR angiography has a number of important advantages because it does not involve radiation exposure or the intravenous injection of an iodinated contrast agent. Thus, if MR angiography were shown to have the same diagnostic accuracy in the detection of coronary artery stenoses as does CT angiography in comparison with the reference standard, conventional coronary angiography, it would likely become the preferred diagnostic test in patients who are suspected of having CAD (5). The aim of this Controversies article, which is accompanied by the article by Sakuma (6), is to provide an overview of the comparative effectiveness of CT angiography and highlight the controversial issues in coronary CT and MR angiography.