HEART VALVES

Atrioventricular ( AV ) Valves

2 atrioventricluar ( AV ) valves prevent backflow into atria when ventricles contract.

Semilunar ( SL ) Valves

2 semilunar valves prevent backflow from major arteries back into ventricles. Open and close in response to pressure changes. Each valve consists of 3 cusps that roughly resemble half a moon.

Chordea Tendineae

Anchor cusps of AV valves to PAPILLARY MUSCLES that function to hold valve flaps in closed position and prevent flaps from everting back into atria

2 major types of valves

Atrioventricular valves, located between atria and ventricles and Semilunar valves, located between ventricles and major arteries.

Heart Valves

Ensure unidirectional blood flow through the heart. They open and close in response to pressure changes. No valves are found between major vein and atria, not a problem because Inertia of incoming blood prevents backflow and heart contractions compress venous openings.

Aortic semilunar valve

Located between left ventricle and aorta.

Pulmonary semilunar valve

Located between right ventricle and pulmonary trunk.

Mitral valve ( left AV valve, bicuspid valve )

Made up of 2 cusps and lies between left atria and ventricle.

Tricuspid valve ( right AV valve )

Made up of 3 cusps and lies between right atria and ventricle.