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Common Congenital Heart Lesions - page 102 / 126





102 / 126

102 of 126

Peripheral Vasculature Diseases – Section 1 DISEASES OF THE AORTA

First, some general review of the aorta: The largest conductance vessel of the vascular system Can break it down into four sections:

Aortic arch

5-6 cm in length three major branches

Descending aorta Abdominal aorta

o brachiocephalic (bifurcates to give right common carotid and right subclavian) o left common carotid o left subclavian from arch, the diameter narrows to 2-2.5 cm subdiaphragmatic provides arteries to abdominal viscera bifurcates into left and right common iliacs, which supply the pelvic organs and lower extremities

Section of Aorta Ascending aorta

Details 3 cm diameter at base of heart (LA)

Aorta is an artery…it is composed of:

  • 1.


    • a.

      endothelial layer

  • 2.


    • a.

      internal elastic lamina

    • b.

      smooth muscle cells

    • c.

      matrix including elastic fibers and collagen, respectively for stretching and strength – in aorta, ratio of elastin to collagen is 2:1, allowing aorta to expand during systole and recoil during diastole

    • d.

      external elastic lamina

  • 3.


    • a.

      collagen fibers

    • b.

      perivascular nerves

    • c.

      vasa vasorum supplies oxygenated blood to the aorta

Aorta’s recoil against the closed aortic valve during diastole is what promotes forward propagation of blood flow.

  • o

    with age, get degeneration of the elastic fibers of the aorta and its branches – collagen becomes

more prominent and arteries stiffen

  • o

    stiffer arteries

increased systolic blood pressure

  • o

    Aorta, thus, with age is subject to injury from mechanical trauma due to high pulsatile pressure

and shear stress.

Diseases of the aorta commonly appear as aneurysm, dissection, or obstruction.

  • o

    Aneurysm and dissection are discussed in the text…I will elaborate on them in colored text boxes

() below…

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