MH 073-074 Heart

Aortic Valve & Cardiac Skeleton
(H&E)

The aortic valve is located between the left ventricle (right side of specimen) and the aorta (left side of the specimen).

• Left Ventricle - receives oxygenated blood from the left atrium and pumps into the system circulation via the aorta. This high workload results in a thick myocardium.
• Aorta - the largest artery in the body and receives blood from the left ventricle.
• Aortic Valve - usually has three leaflets connected with no chordae tendineae or papillary muscles. This section is through one of the leaflets.
  • Endothelium - covers both external surfaces.
  • Dense Connective Tissue - forms the central core of collagen and elastic fibers.
  • Avascular - receive nutrients and oxygen by diffusion from blood in the heart chambers.
• Cardiac Skeleton - framework of dense irregular connective tissue that separates the atria from the ventricles.
  • Fibrous Rings - support heart values and are contain bands of collagen and elastic fibers that appear dark red in this specimen.

Aortic Valve & Cardiac Skeleton
(Phosphotungstic Acid/Hematoxylin)

Phosphotungstic acid/hematoxylin (PTA) is used to demonstrate muscle striations, intercalated discs, nervous tissue and fibrin.

The aortic valve is located between the left ventricle (right side of specimen) and the aorta (left side of the specimen).

• Left Ventricle - receives oxygenated blood from the left atrium and pumps into the system circulation via the aorta. This high workload results in a thick myocardium (dark gray).
• Aorta - the largest artery in the body and receives blood from the left ventricle.
• Aortic Valve - usually has three leaflets connected with no chordae tendineae or papillary muscles. Each leaflet is a thin fold of the endocardium. This section is through one of the leaflets.
  • Endothelium - covers both external surfaces and is continuous at their based with the endocardium.
  • Dense Connective Tissue - forms the central core of collagen and elastic fibers on the ventricular side. At the base of the valves the connective tissue is continuous with the cardiac skeleton.
  • Avascular - receive nutrients and oxygen by diffusion from blood in the heart chambers.
• Cardiac Skeleton - framework of dense irregular connective tissue that separates the atria from the ventricles.
  • Fibrous Rings - support heart values and are contain bands of collagen and elastic fibers that appear pink/red in this specimen.