Peripheral Vascular Procedures

CHAPTER 15


Peripheral Vascular Procedures



CHAPTER OBJECTIVES


After completing this chapter, the reader will be able to perform the following:


image Discuss the vascular anatomy of the upper and lower extremities and the pelvis


image List the various procedures that can be performed in these areas


image List the indications and contraindications for angiography in these areas


image Discuss vessel access for these procedures


image List the contrast agents that are suggested for peripheral angiography


image Discuss the patient positioning for peripheral angiography


image Identify common complications of these procedures


Peripheral angiography involves demonstration of the circulation of the upper and lower extremities. Arteriography of the extremities has gained importance in the identification of many vascular abnormalities, including embolism, aneurysm, and arterial injury, and many bone and soft tissue lesions.


Femoral arteriography involves the entire lower extremity and can be accomplished with a single-film technique, digital subtraction angiography (DSA), single-plane serial radiography, or biplane serial radiography. Femoral arteriography is a commonly performed procedure primarily used to diagnose a variety of vascular diseases and is a common site for percutaneous intervention.


Arteriography on the upper extremity is performed less frequently for arterial disease than for venous pathophysiology. It is also not as frequent an examination as arteriography of the lower extremity.



ANATOMIC CONSIDERATIONS


Arterial Supply


Upper Extremity


The aortic arch gives off three major vessels: the brachiocephalic, left common carotid, and left subclavian arteries (Fig. 15-1). The brachiocephalic artery is the first major branch coming off the aorta. It splits into the right subclavian and the right common carotid arteries.


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FIGURE 15-1 Schematic of the aortic arch and its major branches

The subclavian arteries course over the apex of the lungs and give off several branches. These branches are the vertebral artery, thyrocervical trunk, dorsal scapular artery, costocervical trunk, and internal mammary artery (also known as the internal thoracic artery).


The vertebral artery courses up to enter the skull. This vessel supplies the deep structures in the neck. It also gives off branches referred to as the spinal arteries to supply the spinal cord and the meninges. It then courses into the skull where it joins the basilar artery. The anatomy of the vertebral artery will be discussed in depth in Chapter 16.


Another branch of the subclavian artery that supplies the deep neck structures is the costocervical artery, which, as its name implies, provides the supply for the upper two intercostal spaces. The thyrocervical vessels supply the thyroid gland, superficial neck structures, and upper scapula. Branches to the upper six intercostal spaces, the pleura, pericardium, and the breast are given off by the internal mammary (internal thoracic) artery. The final branch emanating from the subclavian artery is the dorsal or descending scapular artery, which sends branches to the scapular musculature and both surfaces of the scapula.


When the subclavian artery enters the axilla, at approximately the level of the first rib, it becomes the axillary artery. The axillary artery and its branches supply the axilla, shoulder joint, upper humerus, and structures of the chest wall. There are six major branches that arise from the axillary artery: superior thoracic, lateral thoracic, thoracoacromial trunk, subscapular artery, and anterior and posterior humeral circumflex arteries.


Upon leaving the axilla, the axillary artery becomes the brachial artery. Initially, this vessel courses adjacent to the humerus, and as it descends it runs anterior to the humerus until it crosses the humeral epicondyles at the elbow. It gives off several branches, among them the deep brachial artery, the nutrient humeral artery, the superior and inferior ulnar collateral arteries, and its terminal branches are radial and ulnar arteries. The deep brachial artery courses around the posterior of the humerus and provides the blood supply to the triceps muscle. The nutrient artery enters the nutrient canal on the humerus. The ulnar collateral arteries provide an anastomosis with the recurrent ulnar and radial arteries in the forearm.


The terminal branches of the brachial artery are the radial and the ulnar arteries. The ulnar artery is the larger vessel beginning at the cubital fossa (the triangular space at the bend of the elbow) and coursing toward the medial side of the forearm. A branch of the ulnar artery, the common interosseous artery, usually divides into an anterior and posterior branch, which follows the interosseous membrane. Some other branches of the ulnar artery are the anterior and posterior recurrent arteries, the palmar carpal branch, the dorsal carpal branch, and several muscular branches that supply the medial side of the forearm.


The smaller radial artery arises at the level of the radial head and runs down the lateral side of the forearm toward the hand. It gives off the following branches: the radial recurrent artery, the palmar carpal branch, the superficial palmar branch, and several muscular branches.


The radial and ulnar arteries supply the hand with blood. As it passes the wrist, the radial artery moves from the palmar surface to the posterior side of the hand. The ulnar artery passes through the wrist to the palmar side of the hand. These two arteries form the superficial and deep palmar arches. The superficial palmar arch gives off branches, the common palmar digital arteries, which provide the blood supply to the fingers. The deep and superficial arches along with the radial and ulnar arteries supply the thumb and forefinger with blood.



Lower Extremity


At about the level of the fourth lumbar vertebra, the abdominal aorta terminates in a bifurcation. At this point, the aorta becomes the common iliac arteries. These arteries travel for a short distance (about 5 cm), and at about the upper level of the sacrum, they divide into the external and internal iliac arteries.


The internal iliac arteries supply blood to the pelvic region, whereas the external iliac arteries are the origin of the blood supply to the lower extremities (Fig. 15-2,A and B). The external iliac artery courses for about 10 cm before becoming the femoral artery at a point midway between the anterior superior iliac spine and the symphysis pubis. This is also the level at which the femoral artery enters the lower extremity. The branches of the femoral artery are divided into superficial and deep branches, as summarized in Box 15-1.



BOX 15-1   Major Branches of the Femoral Artery


























Superficial Deep
Epigastric Muscular branches
Circumflex iliac Deep external pudendal
External pudendal Deep femoral
  Lateral circumflex
  Medial circumflex
  Descending genicular


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FIGURE 15-2 A, Arteries on the lower limb shown from the anterior and posterior aspects.B, Selected films from a femoral arteriogram depicting the contrast agent in the lower extremity.

As the femoral artery passes into the popliteal space, it becomes the popliteal artery. It courses in a lateral oblique direction to its termination, where it divides into the anterior and posterior tibial arteries. The popliteal artery usually has six major branches—lateral superior genicular, medial superior genicular, middle genicular, lateral inferior genicular, medial inferior genicular, and sural arteries.


The anterior tibial artery courses forward from its origin to descend into the interosseous membrane of the lower leg to the level of the anterior aspect of the ankle joint, where it becomes the dorsalis pedis artery. The major branches of the anterior tibial artery are located around the knee and ankle joints, and many smaller muscular branches are given off along its descending route. The anterior tibial artery is the smaller of the two branches of the popliteal artery.


The posterior tibial artery is a direct continuation of the popliteal artery. Coursing downward toward the ankle, it passes between the medial malleolus of the tibia and the calcaneus and terminates in the foot. As in the anatomy of the anterior tibial artery, the major branches of the posterior tibial artery—the peroneal, nutrient, communicating, posterior medial malleolar, and medial calcaneal arteries—are concentrated around the knee and ankle joints. A summary of the circulation from the level of the anterior and posterior tibial arteries is given in Figure 15-3.


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FIGURE 15-3 Flowchart summarizing the arterial circulation of the lower extremity.


Veins


Upper Extremity


The veins of the body collect the blood from the systemic circulation and return it to the heart and lungs for reoxygenation. The venous system of the body is extensive, and consideration is given here only to major veins with significance in venous angiography. The venous system of the body ultimately empties into two major veins—the inferior and superior venae cavae—which direct the venous blood into the right atrium of the heart (Fig. 15-4). All of the major veins are tributaries of these vessels and compose the venous circulation. The superior vena cava receives blood from the upper portion of the body, and the inferior vena cava serves the lower portion.


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FIGURE 15-4 External and internal anatomy of the right atrium, right ventricle, and the tricuspid orifice. Blood circulation is identified by the arrows.

The venous system of the upper extremity consists of both superficial and deep veins. The deep veins are usually small and paired; they accompany the arteries and ultimately drain into the axillary vein. The veins of the upper extremity contain valves that prevent backflow of the blood and aid in movement of the blood to the heart.


There are two major superficial veins of the upper extremity—the cephalic vein and the basilic vein of the forearm (Fig. 15-5). These vessels are the primary means of drainage in the upper extremity. The cephalic vein starts in the distal forearm, receives the drainage from the dorsal aspect of the hand, runs along the lateral aspect of the arm, and ends just below the clavicle. At this point, the vein courses medially and joins the axillary vein. The median cubital vein forms a connection between the cephalic and the basilic veins of the upper extremity and is located on the anterior aspect of the arm at the level of the elbow. This vein is the usual location for blood sampling, intravenous injection, blood transfusion, and introducing catheters for contrast radiography. The basilic vein runs up from the distal forearm toward the medial side of the arm, where it ultimately becomes the axillary vein. The median vein collects the venous return from the palmar aspect of the hand. It then courses over the anterior of the arm until it joins the basilic vein. In another variant of the normal anatomy, the median vein can also join the median cubital vein. The axillary vein continues a short distance and becomes the subclavian vein at approximately the level of the first rib. The subclavian vein is then joined by the internal jugular vein to form the brachiocephalic vein. The brachiocephalic vein also collects blood from the vertebral, internal mammary, intercostal, and thyroid veins.


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FIGURE 15-5 The superficial branches of the upper limb.

The left and right brachiocephalic veins, which are formed by the union of the internal jugular and subclavian veins, join to form the superior vena cava. The superior vena cava then courses down on the right side of the ascending aorta, where it receives the azygos vein before entering the right atrium of the heart.


The azygos and hemiazygos system comprises unpaired vessels that lie on each side of the spine (Fig. 15-6). There are several normal variants of the anatomic presentation of this system of veins.


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FIGURE 15-6 A, Scheme of the main connections of the azygos, caval, and vertebral systems of veins. Connections of the azygos and hemiazygos veins with the posterior intercostal veins also occur. B, The main veins of the thorax. A dashed line indicates the course of a left superior vena cava (a rare anomaly) on its way to the coronary sinus.

The azygos vein arises at about the level of the right renal vein and courses up to the right of midline. It collects venous blood from a variety of vessels, including the intercostal, subcostal, mediastinal, esophageal, right ascending lumbar, pericardial, bronchial, accessory hemiazygos, and hemiazygos veins. The hemiazygos and accessory hemiazygos veins are located to the left of midline and are considered to correspond to the azygos vein. These vessels collect blood from a variety of vessels on the left side of the body and ultimately empty into the azygos vein for transport to the heart.



Lower Extremity


The venous system of the lower extremity comprises both deep and superficial veins. Unlike in the upper extremity, here the deep veins provide the primary drainage. There is some communication throughout the venous system of the lower extremity; however, this is limited to one-way flow from the superficial system to the deep veins.


The superficial veins are represented primarily by the great and small saphenous veins. The accessory saphenous vein also contributes to the return of blood from the lower extremity, when it is present. It is usually located over the posteromedial aspect of the thigh and communicates with both the great and small saphenous veins. The great saphenous vein originates at the medial side of the foot at the level of the median marginal vein. It continues in front of the medial malleolus, ascends along the anteromedial aspect of the lower leg and thigh, and ends in the common femoral vein. The location of this vessel at the medial malleolus provides an excellent avenue for intravenous administration of medications, if necessary. The small saphenous vein, also called the lesser saphenous vein, originates on the lateral side of the foot at the level of the lateral marginal vein. It then courses toward the posterior of the lower leg and ascends to above the knee joint. Several normal variants may be present at this level, and the small saphenous vein joins the popliteal, greater saphenous, or deep muscular calf veins (Fig. 15-7).


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FIGURE 15-7 Schematic drawing of the superficial veins of the lower extremity. For ease of visualization only the major vessels are included.

The deep veins of the lower extremity consist primarily of the femoral and popliteal. These are usually paired and accompany the arteries. These normally originate with the vessels in the plantar surface of the foot and follow the course of the anterior tibial, posterior tibial, and peroneal arteries. The anterior and posterior tibial veins ascend to just below the level of the knee, where they anastomose to form the popliteal vein (Fig. 15-8). At approximately the level of midthigh, the popliteal veins become the superficial femoral vein. This vein ascends until it is joined by the deep femoral vein. This occurs about 5 to 10 cm below the inguinal ligament; the resultant vessel is called the common femoral vein. The common femoral vein becomes the external iliac vein above the inguinal ligament. It connects with the internal iliac vein to become the common iliac vein. At about the level of the fifth lumbar vertebra, the left and right iliac veins join to become the inferior vena cava.


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FIGURE 15-8 The major veins of the lower leg as they would appear in a normal venogram. A, Anteroposterior projection. B, Lateral projection.

As in all veins, those of the lower extremity have thinner walls than the arteries and are equipped with valves to prevent the backflow of blood. The veins of the lower extremity begin as small channels; they are both superficial and deep in the foot. There are more valves in the deep-set veins; the veins become progressively larger along their ascending courses. These veins run with the arteries and are named similarly. The veins of the superficial group collect in the great and small saphenous veins.


The veins of the deep-set group and those of the small saphenous vein empty into the popliteal vein, whereas the great saphenous vein drains into the femoral vein. From this point, the blood flows up through the external and common iliac veins and ultimately into the inferior vena cava to the heart.


A summary of the venous circulation of the lower extremity is given in Figure 15-9.


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FIGURE 15-9 Flowchart summarizing the venous circulation of the lower extremity.


Pelvic Circulation


The abdominal aorta bifurcates at the level of the fourth lumbar vertebra forming the left and right common iliac arteries. As the common iliac arteries approach the level of the sacrum, they once again divide into the external and internal iliac arteries. These are the only normal branches off the common iliac arteries.


Table 15-1 summarizes the branches that arise from the external and internal iliac arteries.


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Feb 27, 2016 | Posted by in GENERAL RADIOLOGY | Comments Off on Peripheral Vascular Procedures

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