The aorta and peripheral arteries are of significant importance to the interventional cardiologist. The angiographic appearance of a number of clinical entities including aneurysmal disease, dissection, and occlusive disease is important to know. Moreover, knowledge of important complications of vascular access procedures and intervention as well as anatomic variants that may complicate catheter-based procedures is important to recognize. This chapter focuses on the aorta and major branches as well as several disease processes that are relevant to the interventional cardiologist.

The aorta can be divided into the ascending, transverse, descending, and abdominal segments (FIGURE 13.1A; Video 13.1). The ascending aorta arises after the aortic valve, and its first branches are the coronary arteries. The brachiocephalic artery, also known as innominate artery, arises from the ascending aorta and gives rise to the right subclavian artery and the right carotid artery. Most commonly, the left carotid artery is the next branch arising from the transverse aorta followed by the left subclavian artery. Typically, the vertebral arteries arise as the first branches of the subclavian arteries (FIGURE 13.1).

Commonly, the left carotid artery can arise from the innominate artery (FIGURE 13.2). This variation is often called a “bovine arch”, an inaccurate term. A true bovine arch has a single brachiocephalic origin that gives rise to a right subclavian, a bicarotid vessel that gives rise to the right and left carotid arteries and a left subclavian branch. The next most common aortic variant occurs when the left vertebral artery arises directly from the aorta (FIGURE 13.3).

When an aberrant right subclavian artery variant is present, the brachiocephalic trunk is absent. The right common carotid artery, the left common carotid artery, and the left subclavian artery arise from the aorta followed by the right subclavian artery, which arises from the aorta at the proximal descending aorta (FIGURE 13.3). Also called the arteria lusoria, it crosses the middle line of the body while traveling to the right arm and usually passes behind the esophagus. If the artery compresses the esophagus, it may produce a condition called dysphagia lusoria. Frequently, it arises from an aortic arch diverticulum at the proximal descending aorta, first described by Kommerell. This anomaly can make catheterization via the right radial approach challenging.

Acute aortic ascending arch dissection may be identified during cardiac catheterization for patients with suspectedmyocardial infarction orcardiac tamponade (FIGURE 13.4A; Video 13.2). The intimal flap is visible as well as a dilated ascending arch with contrast filling both the true and false lumens. Moderate aneurysmal dilation of the ascending aorta is seen with magnetic resonance angiography in FIGURE 13.4B Pseudocoarctation may be present if the aorta is

redundant as in the magnetic resonance angiogram in FIGURE 13.4BC. The absence of dilated intercostal vessels and reduced blood pressure in the lower extremities suggests the diagnosis of pseudocoarctation.

The angiogram in FIGURE 13.5 shows a right aortic arch with true coarctation. This patient has had a bypass graft for this disorder. FIGURE 13.6 shows a graft with numerous stents arising most proximally and then the right carotid artery; the coarcted portion of the aorta appears next, and then the right subclavian originates. The graft attaches to the descending aorta and finally an aberrant left innominate giving rise to the subclavian and left common carotid artery. FIGURE 13.7 demonstrates filling of the graft.

Selective left subclavian angiography reveals the left vertebral artery and left internal mammary artery as well as stenosis before and after repair (FIGURE 13.8A and B). Subclavian stenosis may compromise flow to the left internal mammary artery, which may lead to coronary ischemia if this vessel has been used for coronary artery bypass surgery. The subclavian stenosis in FIGURE 13.9A and Video 13.3 was found in a patient with shock and acute myocardial infarction. FIGURE 13.9B and Video 13.4 show the artery after stent placement with improved flow in the mammary artery.

The thoracic aorta can develop aneurysmal disease. Fusiform dilation is common. FIGURE 13.10 demonstrates dilation due to contained rupture of mycotic aneurysm. This was repaired with an aortic stent graft as shown in FIGURE 13.11. The left subclavian artery is partially occluded by the covered stent and fills faintly. FIGURE 13.12 demonstrates significant thoracic aortic tortuosity on computed tomography (CT) in a patient with severe kyphoscoliosis.

The abdominal aorta begins at the aortic hiatus of the diaphragm. FIGURE 13.13A is a lateral view where the celiac artery takes off as the most superior vessel and courses anteriorly in this view. The superior mesenteric artery also takes off anteriorly and then courses inferiorly. The renal arteries can be seen to take off and course posteriorly. FIGURE 13.13B demonstrates these
same vessels in the anteroposterior projection. Nonselective angiography in the lateral projection demonstrates a stenosis in the celiac artery and occlusion of the superior mesenteric artery (FIGURE 13.14).