Functional cardiac CT angiography

Despite the anatomical assessment of the coronary artery tree being a cornerstone in diagnosing coronary artery disease (CAD), it is well established that the pure morphological assessment obtained with cardiac computed tomography angiography (CCTA) does not provide a comprehensive overview of patient risk due to the fact that the anatomic relevance of coronary stenosis does not necessarily correlate with its hemodynamic significance. To address this predicament, novel CT acquisition techniques and post-processing software have been introduced in recent years. CT myocardial perfusion imaging (CT-MPI) and CT-derived Fractional Flow Reserve (CT-FFR) are two cutting-edge and promising techniques that could provide a comprehensive anatomical and functional assessment of the coronary artery tree and the myocardium with a single examination; ultimately allowing CT to become the “one-stop-shop” imaging modality to diagnose CAD. CTMPI enables the assessment of myocardial infarct size, the identification of dysfunctional tissue, and evaluation of ventricular function, while CT-FFR is able to assess the hemodynamic significance of a coronary plaque. Individually, or perhaps collectively, these techniques could provide valuable information to physicians, which could be beneficial in developing an effective tailored patient management strategy. This chapter provides a comprehensive technical overview of these two techniques, along with a summarized analysis of the current literature.