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Physicians should embrace non-invasive coronary angiography as a helpful addition to the armamentarium with which to diagnose and help combat cardiovascular disease. In selected patients, coronary CTA can be useful to rule out significant coronary artery or bypass graft stenoses and this helps avoid unnecessary invasive coronary angiograms. In the future, an important application may be in the anatomic definition of plaque burden and composition. Technical improvements will continue to broaden the spectrum of patients who may profit from computed tomographic imaging of the coronary arteries.

Two-dimensional images are the basis for interpretation of all CT imaging, including CT angiography. Understanding the anatomy, being able to track the structures on consecutive slices, and ultimately diagnosing these studies accurately will be dependent on the CT user’s understanding of the axial images and corresponding anatomy. This is probably the most important skill to learn, as virtually all diagnoses can be made based solely on the original axial image set. Analysis of the 2-D images has been shown to be as accurate for the diagnosis of obstructive CAD as 3-D imaging, and superior to some reconstruction methods (see Chapter 4).

There have been extensive validations using EBCT for virtually all cardiac size, shape, and functional measures and these were established long before such measures were attempted by MRI. Recent improvements in spiral/helical CT have also accorded this validity to MDCT. CT then becomes a very robust method to define the heart and its detailed anatomy in health and in disease. Furthermore, these types of measures can be accomplished during postprocessing of images intended to define coronary artery anatomy, generally without the need for additional imaging. The disadvantage is that additional sets of cardiac data are required at various portions of the cardiac cycle (nominally at end-diastole and end-systole) and this then obligates concomitant increases in radiation exposure to the patient. That said, CT is a very robust method that can function as both a primary method and a complementary method (such as to echocardiography, contrast ventriculography, radionuclide angiography, and MRI) to quantitate details of cardiac anatomy and function.

During the past decade, we have been witness to a tremendous development in the field of CT imaging. CTA has gained remarkably by improvements in scan time and image quality, replacing diagnostic angiography in many cases of peripheral, carotid, and renal angiography. These vascular beds do not suffer from motion artifacts, so imaging with CT is ideal. CTA is less expensive, less invasive, and allows simultaneous visualization of large anatomic areas from multiple angles using 3-D display. Nevertheless, along with exciting advances, MDCT also carries some emerging and important issues such as increased patient radiation exposure and continued exposure to iodinated contrast.

Cardiovascular magnetic resonance imaging provides a multifaceted and comprehensive assessment for the diagnosis and treatment of cardiovascular disease, including cardiovascular structures, function, tissue characterization, myocardial perfusion, and metabolism. Applications include the assessment of coronary artery disease, pathologic myocardial substrates, congenital heart disease, thoracic vasculature, valvular function, masses, and electrophysiologically relevant substrates. Advances in technology will continue to lead to novel clinical and research applications.

Physicians should embrace non-invasive coronary angiography as a helpful addition to the armamentarium with which to diagnose and help combat cardiovascular disease. In selected patients, coronary CTA can be useful to rule out significant coronary artery or bypass graft stenoses and this helps avoid unnecessary invasive coronary angiograms. In the future, an important application may be in the anatomic definition of plaque burden and composition. Technical improvements will continue to broaden the spectrum of patients who may profit from computed tomographic imaging of the coronary arteries.

This review has indicated that there is an interaction between the assessment of coronary anatomic abnormality — through the CCS or possibly even the non-invasive coronary angiogram — and the assessment of the functional consequences of atherosclerosis using gated MPS. Additional information of clinical importance may come from assessment of biomarkers of inflammation such as high-sensitivity CRP. It is considered likely that with an increased emphasis on prevention and a concomitant aging of the population, many forms of non-invasive cardiac imaging will continue to grow. The CCS and non-invasive CT coronary angiography approaches are likely to grow greatly in the preventive arena for the early detection of coronary atherosclerosis, in guiding the aggressiveness of medical therapy in these patients, and in detection of significant CAD. Gated MPS is likely to have its greatest growth in the increasing numbers of patients with known CAD, as the most effective method to identify which of these patients are most likely to benefit from medical therapy versus coronary revascularization or myocardial reshaping procedures.

The ability of CT angiography to comprehensively assess cardiovascular structure and function makes it a robust technology for the assessment, treatment, and follow-up of patients with electrophysiologically related disease processes. Cardiovascular CT angiographic imaging holds the promise to continue to advance the field of cardiac electrophysiology through understanding of electrophysiologically relevant pathologic substrates and facilitation of novel interventional approaches. This effort will be enhanced by a multidisciplinary approach to diagnosis and therapeutic intervention in patients with electrophysiologically relevant issues.