6 | Reviews International Cardiovascular Forum Journal 6 (2016) DOI: 10.17987/icfj.v6i0.181 Beyond the Coronary Arteries: Evolving Applications of Multi-detector Cardiac Computed Tomography in the Assessment of Non-coronary Structures Bo Xu, Sujith Seneviratne, Arthur Nasis MonashHeart, Monash Medical Centre, Melbourne, Australia Corresponding author; Dr. Bo Xu, MonashHeart, Monash Medical Centre, Melbourne, Australia e-mail: greatbear227@hotmail.com Introduction The ability of MDCT to obtain a three-dimensional volumetric dataset of the entire heart and adjacent structures that can be reconstructed at any point in the cardiac cycle makes it a powerful tool for the assessment of cardiac structures. This review will focus on the evolving niche applications of MDCT in the assessment of non-coronary structures, including the evaluation of the left ventricle for perfusion and scar, the evaluation of the right ventricle, the evaluation of congenital heart disease, pericardial disease, coronary anomalies and intra-cardiac masses. Evaluation of Non-Coronary Cardiac Structures A large number of non-coronary cardiac structures can be studied during a routine MDCT examination. These structures include the cardiac chambers, particularly the left-sided cardiac chambers, the cardiac valves, pulmonary arteries and veins, thoracic aorta and its proximal branches, cardiac veins and pericardium. Left ventricular (LV) and left atrial walls and cavities as well as left-sided valves are uniformly opacifed in a standard MDCT examination. In comparison, right-sided cardiac chambers, walls and valves may be suboptimal for interpretation due to variability in contrast infusion protocol. Structural heart abnormalities may be more common than appreciated. A large observational study of 4,543 patients who underwent MDCT for assessment of suspected coronary artery disease, demonstrated 4.4% patients had structural heart disease unrelated to atherosclerosis, with 25% of these patients having previously undiagnosed abnormalities and 30% of these patients requiring specifc treatment. 1 Left Ventricle: Evaluation of Perfusion and Scar An emerging clinical application of MDCT is the ability to evaluate LV myocardial perfusion and detect previous myocardial infarction. In comparison to gated single photon emission computed tomography and CMR, MDCT has high accuracy in detecting myocardial infarction, although it tends to slightly overestimate the area of infarcted myocardium. 2,3 Measurement of myocardial blood fow by computed tomography was frst quantifed using electron-beam computed tomography by applying the principles of indicator- dilution theory. 4,5 MDCT perfusion data are acquired during the early portion of frst-pass circulation of iodinated contrast, as iodinated contrast agents are predominantly intravascular during early frst-pass circulation and difuse to the extravascular space over time. Normally, after one minute of injection, the extravascular iodine concentration exceeds the intravascular iodine concentration. 6 In regions of myocardium subtended by stenosed coronary arteries, resulting in reduced perfusion, the rate of extravascular difusion of iodinated contrast is more pronounced. 7 Hypo-perfused myocardium (which represents reduced myocardial blood fow) * Corresponding author. E-mail: greatbear227@hotmail.com Abstract Beyond the assessment of coronary artery anatomy, multi-detector computed tomography (MDCT) can be used to provide detailed structural evaluation of multiple non-coronary structures. The purpose of this review is to provide a clinical update on the evolving niche applications of MDCT in the assessment of non-coronary structures, including the assessment of the left ventricle for perfusion and scar, the evaluation of the right ventricle, pericardium and coronary anomalies. Additionally, an overview of the roles of MDCT in the assessment of congenital heart disease and intra-cardiac masses will be reviewed. Key words: Multi-detector computed tomography; Structural heart disease; Coronary anomaly; Pericardial disease; Congenital heart disease Citation: Xu B, Seneviratne S, Nasis A. Beyond the Coronary Arteries: Evolving Applications of Multi-detector Cardiac Computed Tomography in the Assessment of Non-coronary Structures. International Cardiovascular Forum Journal 2016;6:6-12. DOI: 10.17987/icfj.v6i0.181 ISSN: 2410-2636 © Barcaray Publishing