Page 727 - Fundamentals of anatomy physiology

714 Unit 4 Fluids and Transport Left common Left subclavian artery
carotid artery
Figure 20–3 The Position and Superficial Arch of aorta
Anatomy of the Heart. Brachiocephalic
trunk Ligamentum
Base of heart arteriosum
11 Ribs Ascending
aorta Descending
2 2 Right aorta
3 Superior atrium Left pulmonary
3 vena cava artery
4
4 Auricle Pulmonary
5 5 of right trunk
6 atrium
6 Auricle of
7 7 Right left atrium
8 8 ventricle
9 9 Fat and vessels
10 10 Apex of Fat and in anterior
heart vessels in interventricular
coronary sulcus

sulcus Left
ventricle

a Heart position relative to the rib cage. b Major anatomical features on the anterior surface.

Left subclavian artery Ligamentum Left pulmonary artery Left Arch of aorta
Left common carotid arteriosum Left pulmonary veins atrium
Left pulmonary Right pulmonary
artery artery Fat and vessels Right artery
Brachiocephalic trunk Pulmonary in coronary ventricle
trunk sulcus Superior
Ascending Auricle of left atrium Coronary vena cava
aorta sinus
20 Left coronary artery Right
Superior (LCA) Left pulmonary
vena cava ventricle Right veins
Anterior atrium (superior
Auricle of interventricular and inferior)
right atrium sulcus

Right atrium Left
ventricle
Right Right Inferior
coronary ventricle Anterior vena cava
interventricular
artery branch of LCA

Coronary sulcus

Marginal branch Fat and vessels in posterior
of right coronary artery interventricular sulcus

c Anterior surface of the heart, cadaver dissection. d Major landmarks on the posterior surface. Coronary
arteries (which supply the heart itself ) are shown in
red; coronary veins are shown in blue.

2. The myocardium, or muscular wall of the heart, forms around both ventricles, and deeper muscle layers spiral
the atria and ventricles. This layer contains cardiac muscle around and between the ventricles toward the apex in a
tissue, blood vessels, and nerves. The myocardium consists figure-eight pattern.
of concentric layers of cardiac muscle tissue. The atrial
myocardium contains muscle bundles that wrap around 3. The endocardium covers the inner surfaces of the heart,
the atria and form figure eights that encircle the great ves- including those of the heart valves. This simple squamous
sels (Figure 20–4b). Superficial ventricular muscles wrap epithelium is continuous with the endothelium of the
attached great vessels.