5. Noninvasive Coronary Artery Imaging with CT and MRI

Cardiac CT angiography (CCTA) for coronary artery evaluation is now a clinically useful modality as a result of concurrent developments in computer speed and memory, and powerful multidetector CT scanner hardware with post-processing software. For many years, invasive coronary angiography was the gold standard for evaluating coronary artery disease since it provides a clear view of the coronary artery. But, it comes with a small risk of associated morbidity. Noninvasive coronary artery evaluation previously relied on phenomena secondary to coronary stenosis during physiologic stress (electrocardiogram, wall motion, and perfusion changes), but multiple problems with test performance still limit sensitivity and specificity. CCTA of the coronary artery lumen and wall permits noninvasive visualization, prognosis assessment, and an ability to determine the potential source of symptoms. In this chapter, we review CCTA techniques, data supporting its clinical application, clinical uses, associated radiation exposure, and future directions.