Heart valves and heart sounds Flashcards
What are the valves in the heart?
The valves are actually pointed flaps or cusps.
How many flaps do most heart valves have?
Most heart valves have three flaps, except the bicuspid or mitral valve, which has two.
What produces the characteristic “lubb-dubb” sounds of the heartbeat?
Closure of the heart valves produces the “lubb-dubb” sounds characteristic of the heartbeat.
What are Atrioventricular (AV) Valves?
Between the atria and the ventricles. Each AV valve is named for its location, number of cusps, or shape. The “lubb” is the low-pitched sound generated by blood turbulence from closure of both AV valves.
What is the Tricuspid Valve (Right AV Valve)?
Between the right atrium and the right ventricle.
What is the Bicuspid/Mitral Valve (Left AV Valve)?
Between the left atrium and the left ventricle. The bicuspid valve is also called the mitral valve because it is shaped like a miter or bishop’s hat.
What are Semilunar (SL) Valves?
Between the ventricles and large blood vessels, such as the pulmonary trunk and the aorta. Each SL valve is named for the vessel it leads to. The “dubb” is the second higher-pitched sound caused by blood turbulence from closure of both the SL valves.
What is the Pulmonary Valve (Right SL Valve)?
Between the right ventricle and the pulmonary trunk.
What is the Aortic Valve (Left SL Valve)?
Between the left ventricle and the aorta.
What are chordae tendineae?
Tendonlike cords that hold the tricuspid and bicuspid/mitral valves in place. They are attached to the heart wall by papillary muscles.
Why are chordae tendineae important?
Chordae tendineae keep the valve flaps from opening backward, or prolapsing, when the ventricles contract. This ensures blood moves forward through the heart instead of surging back into the atria.
