Atrioventricular valves

(noun)

These valves separate the atria from the ventricles on each side of the heart and prevent backflow from the ventricles into the atria during systole. They include the mitral and tricuspid valves.

Related Terms

Examples of Atrioventricular valves in the following topics:

  • Operation of Semilunar Valves

    • These valves do not have chordae tendineae, and are more similar to valves in veins than to atrioventricular valves.
    • The semilunar valves act in concert with the atrioventricular valves to direct blood flow in the heart.
    • When the atrioventricular valves are open, the semi lunar valves are shut and blood is forced into the ventricles.
    • When the atrioventricular valves shut, the semilunar valves open, forcing blood into the aorta and pulmonary artery.
    • Describe the operation of the semilunar valves, the aortic and pulmonary valves

  • Operation of Atrioventricular Valves

    • The atrioventricular valves separate the atria from the ventricles and prevent backflow from the ventricles into the atria during systole.
    • A heart valve allows blood flow in only one direction through the heart, and the combination of the atrioventricular and semi-lunar heart valves determines the pathway of blood flow.
    • Valves open or close based on pressure differences across the valve.
    • The atrioventricular (AV) valves separate the atria from the ventricles on each side of the heart and prevent backflow of blood from the ventricles into the atria during systole.
    • Describe the operation of the atrioventricular valves: bicuspid (mitral) and tricuspid

  • Structures of the Heart

    • The heart pumps blood through the body with the help of structures such as ventricles, atria, and valves.
    • This deoxygenated blood then passes to the right ventricle through the right atrioventricular valve (tricuspid valve), a flap of connective tissue that opens in only one direction to prevent the backflow of blood.
    • The valve separating the chambers on the left side of the heart is called the biscuspid or mitral valve (left atrioventricular valve).The blood passes through the bicuspid valve to the left ventricle where it is pumped out through the aorta, the major artery of the body, taking oxygenated blood to the organs and muscles of the body.
    • Once blood is pumped out of the left ventricle and into the aorta, the aortic semilunar valve (or aortic valve) closes, preventing blood from flowing backward into the left ventricle.
    • One-way valves separate the four chambers.

  • The Cardiac Cycle

    • The atria contract at the same time, forcing blood through the atrioventricular valves into the ventricles.
    • Closing of the atrioventricular valves produces a monosyllabic "lup" sound.
    • Closing of the semilunar valves produces a monosyllabic "dup" sound.
    • The signal is initiated at the sinoatrial valve.
    • The signal is (b) delayed at the atrioventricular node before it is passed on to the (c) heart apex.

  • Heart Murmurs

    • Heart murmurs are pathologic heart sounds indicative of valve and blood flow abnormalities.
    • Yet most heart problems do not produce any murmur and most valve problems also do not produce an audible murmur.
    • Anatomical sources of heart murmurs include stenosis of the bicuspid aortic valve which tends to appear between 40 and 70 years of age, and stenosis of the tricuspid aortic valve where symptoms more likely to appear after 80 years of age.
    • The first heart sound is caused by the atrioventricular valves--Mitral (M) and Tricuspid (T)--and the second heart sound is caused by the semilunar valves--Aortic (A) and Pulmonary/Pulmonic (P).
    • Heart murmurs are often the result of leaky valves.

  • Anatomy of the Heart

    • The atria and ventricle on each side of the heart are linked together by valves that prevent backflow of blood.
    • The pulmonary vein and aorta also have valves connecting them to their respective ventricle.
    • The sinoatrial (SA) and atrioventricular (AV) nodes are bundles of nerve fibers that form this conduction system.
    • It also merges with the inner lining of blood vessels and covers heart valves.
    • The position of valves ensures proper directional flow of blood through the cardiac interior.

  • Heart Valve Disorders

    • Valvular heart disease is any disease process involving one or more of the valves of the heart (the aortic and mitral valves on the left and the pulmonary and tricuspid valves on the right).
    • Valvular heart disease includes aortic and mitral valve disorders, and pulmonary and tricuspid valve disorders.
    • Pulmonary valve diseases are the least common heart valve disease in adults.
    • The most common types of pulmonary valve diseases are: pulmonary valve insufficiency, pulmonary valve incompetence, and pulmonary valve regurgitation.
    • Both tricuspid and pulmonary valve diseases are less common than aortic or mitral valve diseases due to the lower pressure those valves experience.

  • Heart Sounds

    • The two major heart sounds are "lub" (from the closure of AV valves) and "dub: (from the closure of aortic and pulmonary valves).
    • The closing of the heart valves produces a sound.
    • S2 is split because aortic valve closure occurs before pulmonary valve closure.
    • During inspiration (breathing in) there is slightly increased blood return to the right side of the heart, which causes the pulmonary valve to stay open slightly longer than the aortic valve.
    • Abnormal heart sounds may indicate problems with the health of the valves.

  • Pumps and the Heart

    • The septum divides the left and right side of the heart, while the valves of the heart ensure that blood only flows in one direction.They include the tricuspid valve-found between the right atrium and the right ventricle-and the mitral valve-found between the left atrium and the left ventricle.
    • The list of heart valves also includes the semi-lunar valves, which are located at the bottom of the aorta and pulmonary artery.
    • Strong tendinous chords attached to valves prevent them from turning inside out when they close.
    • The heart beat can be heard as a sound that the valves make when they close.
    • The ‘lub' sound is made when the atrio ventricular valves close and the ‘dub' sound is made when the semi lunar valves close.

  • Bacterial Infections of the Heart

    • If a heart valve is damaged and covered with a piece of blood clot, the valve provides a place for the bacteria to attach themselves and an infection can be established.
    • The valves of the heart do not receive any dedicated blood supply.
    • When bacteria attaches to a valve surface and forms a vegetation, the host immune response is blunted.
    • The lack of blood supply to the valves also has implications for treatment, since drugs also have difficulty reaching the infected valve.
    • Normally, blood flows smoothly through these valves.