For the Greek punctuation mark sometimes known as the diastole, see Hypodiastole.
Diastole (/daɪˈæstəli/dy-AST-ə-lee) is the relaxed phase of the cardiac cycle when the chambers of the heart are refilling with blood. The contrasting phase is systole when the heart chambers are contracting. Atrial diastole is the relaxing of the atria, and ventricular diastole the relaxing of the ventricles.
The term originates from the Greek word διαστολή (diastolē), meaning "dilation",[1] from διά (diá, "apart") + στέλλειν (stéllein, "to send").
^Diastole. Merriam-Webster Online Dictionary. 24 August 2008.