diastole

di·as·to·le   (dī-ās'tə-lē)    n.   Physiology The normal rhythmically occurring relaxation and dilatation of the heart chambers, especially the ventricles, during which they fill with blood. The lengthening of a normally short syllable in Greek and Latin verse. [Greek diastolē, dilation, separation, from diastellein, to expand : dia-, apart; see dia- + stellein, to place, send; see stel- in Indo-European roots.] di'as·tol'ic (dī'ə-stŏl'ĭk) adj.

Main Entry: di·as·to·le
Pronunciation: dI-'as-t&-(")lE
Function: noun
1 : the passive rhythmical expansion or dilation ofthe cavities of the heart during which they fill with blood —compare SYSTOLE
2 : the rhythmicalexpansion of a pulsating vacuole (as of an ameba) —di·a·stol·ic /"dI-&-'stäl-ik/ adjective

diastole di·as·to·le (dī-ās'tə-lē)
n.
The normal rhythmically occurring relaxation and dilatation of the heart chambers, especially the ventricles, during which they fill with blood.

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di'a·stol'ic (dī'ə-stŏl'ĭk) adj.

diastole   (dī-ās'tə-lē)  Pronunciation Key  The period during the normal beating of the heart in which the chambers of the heart dilate and fill with blood. Diastole of the atria occurs before diastole of the ventricles. Compare systole. diastolic adjective (dī'ə-stŏl'ĭk)

diastole

in the cardiac cycle, period of relaxation of the heart muscle, accompanied by the filling of the chambers with blood. Diastole is followed in the cardiac cycle by a period of contraction, or systole (q.v.), of the heart muscle. Initially both atria and ventricles are in diastole, and there is a period of rapid filling of the ventricles followed by a brief atrial systole. At the same time, there is a corresponding decrease in arterial blood pressure to its minimum (diastolic blood pressure), normally about 80 mm of mercury in humans. Ventricular diastole again occurs after the blood has been ejected (during ventricular systole) into the aorta and pulmonary artery.

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