Comparison of multimodality imaging

To understand the role, place, and timing of cardiovascular CT imaging in the assessment and management of cardiac patients, it is important to recognize the value and limitations of currently available techniques. This chapter summarizes these alternative techniques; for more in-depth information the reader is directed to the relevant dedicated Oxford Specialist Handbook.

Accreditation and certification in cardiovascular CT

Although radiologists and cardiologists receive core training in cardiovascular physiology and imaging, subspecialty practice in CCT requires specific training. To this end, international levels of clinical competency have been established that are now widely accepted. Certification exams in CCT are available via several US and European institutions. Some are linked to the process of accreditation, whilst others (e.g. CBCCT) are separate from that process (but have similar requirements).

Systemic veins

Most contrast-enhanced scanning protocols of the thorax are designed to provide optimal visualization of the lungs, pulmonary arteries, heart, or aorta and its branches. Nevertheless, the systemic venous system is routinely imaged during CT examinations, but is often regarded as of secondary importance to the main indication for the scan. However, there are many clinical situations where the visualization of the systemic veins is of prime interest. These include assessment of SVC obstruction, IVC involvement, potential access routes for central venous line wire placement, and pre-operative assessment.

Radiation physics, biology, and protection

This chapter describes the interactions of X-rays with matter, the biological effects of ionizing radiation (including estimated dose thresholds), the science behind radiation dosimetry, and principles of protection of people and the environment. It goes on to describe patient dose according to scanner design, scan parameters, and methods to manage and optimize radiation doses.

Peripheral arterial imaging

Accurate mapping and assessment of the upper limb, abdominal, and pelvic arterial tree has become a standard CT request and is now a pre-requisite for appropriate planning of interventional procedures in the thorax. In particular, the delivery systems of interventional devices (such as transcatheter aortic valve implantation have a minimum requirement for vessel calibre. Marked tortuosity of the vessels that comprise the access route to cardiac or thoracic vascular structures will also influence the choice of procedure undertaken. Further information may also be required on other important structures such as the mesenteric and renal vessels. This chapter will not deal with peripheral vascular disease below the inguinal ligaments.

Non-cardiac findings on cardiac CT

In addition to imaging the heart and coronary arteries, cardiac CT visualizes a variety of non-cardiac structures. This includes lung parenchyma, mediastinum, upper abdominal structures, pleura, bones, and chest wall. Each of these systems has numerous potential pathologies, some of which may be the cause of the patient’s symptoms (such as pulmonary embolism or aortic dissection) or additional findings that require further investigation or treatment. Others are of no clinical importance, such as common anatomical variants.

Ventricular pathology

Cardiac CT is most commonly performed for the evaluation of coronary artery disease in symptomatic patients. While abnormalities of myocardial structure and function are not common in patients undergoing coronary CT angiography, cardiac CT is a highly accurate test for abnormalities involving the right and left ventricles. Readers performing cardiac CT should be familiar with cardiomyopathies, as well as the appearance of cardiac masses. This chapter covers the assessment of the left and right ventricles, ventricular dysfunction, the CT appearance of cardiomyopathies, cardiac masses, and tumours (benign, malignant, and pseudo).

Coronary stent imaging

Percutaneous coronary intervention (PCI) with stent implantation is now the most common form of coronary revascularization. This chapter covers an introduction to coronary stent imaging, and further details including the blooming effect, technical requirements, diagnostic performance, and new developments.

The coronary arteries and cardiac veins

This chapter describes the anatomy of the coronary arteries and cardiac veins. It covers the coronary ostia and left coronary artery, the right coronary artery, the cardiac venous system, and the coronary sinus and its tributaries.

Difficult scenarios

This chapter describes difficult scenarios in CT scanning and general methods of avoiding or minimizing potential problems. Acquisition of high-quality images in coronary CTA requires a regular heart rate. Optimal image quality is achieved with contemporary MSCT scanners at heart rates under 60 bpm. Prospectively gated acquisitions are particularly dependent on a regular heart rate, and artefact, and mis-registration of data will inevitably occur in the presence of cardiac dysrhythmias. It also describes difficulties in obtaining scans in morbidly obese patients and children.