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    Can someone give me a brief explanation of Cardiac Diastole?

    All I've got is...

    Atria and ventricles relax due to low pressure which causes elastic recoiling of the heart. Semilunar valves close, coronary arteries fill and the low pressure in the atria draws blood back to the heart from the veins.
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    (Original post by Philip-flop)
    Can someone give me a brief explanation of Cardiac Diastole?

    All I've got is...

    Atria and ventricles relax due to low pressure which causes elastic recoiling of the heart. Semilunar valves close, coronary arteries fill and the low pressure in the atria draws blood back to the heart from the veins.
    I'm not sure how much detail you are after but this is a fairly basic explanation

    At any given time the ventricles of the heart can either be in systole or diastole. During systole the depolarization of the heart muscle causes contraction of the cardiac myocytes, increasing the intracardiac pressure and therefore forcing blood out of the ventricles through the semilunar (Pulmonary and aortic) valves and into the great vessels. The valves open because the pressure in the ventricles exceeds that in the arteries.
    At the end of systole the cardiac myocytes become refractory and then repolarize (Diastole), this causes relaxation of the cardiac myocytes and therefore the ventricles. The relaxation causes a drop in pressure in the ventricles to a point where it is lower than the pressure that exists in the arteries, as a result of this the semilunar valves are forced closed. During systole the aortic pressure (required to maintain peripheral tissue perfusion) drops but is maintained to a physiologically adequate level by the elastic recoil of the main arteries.
    Hope this is helpful
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    (Original post by Tenrec)
    I'm not sure how much detail you are after but this is a fairly basic explanation

    At any given time the ventricles of the heart can either be in systole or diastole. During systole the depolarization of the heart muscle causes contraction of the cardiac myocytes, increasing the intracardiac pressure and therefore forcing blood out of the ventricles through the semilunar (Pulmonary and aortic) valves and into the great vessels. The valves open because the pressure in the ventricles exceeds that in the arteries.
    At the end of systole the cardiac myocytes become refractory and then repolarize (Diastole), this causes relaxation of the cardiac myocytes and therefore the ventricles. The relaxation causes a drop in pressure in the ventricles to a point where it is lower than the pressure that exists in the arteries, as a result of this the semilunar valves are forced closed. During systole the aortic pressure (required to maintain peripheral tissue perfusion) drops but is maintained to a physiologically adequate level by the elastic recoil of the main arteries.
    Hope this is helpful
    Thank you!! That was very descriptive but very useful
 
 
 
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