Systole vs. Diastole — What's the Difference?

The systole ( SIST-ə-lee) is the part of the cardiac cycle during which some chambers of the heart muscle contract after refilling with blood. The term originates, via New Latin, from Ancient Greek συστολή (sustolē), from συστέλλειν (sustéllein 'to contract'; from σύν sun 'together' + στέλλειν stéllein 'to send'), and is similar to the use of the English term to squeeze.

Diastole ( dy-AST-ə-lee) is the part of the cardiac cycle during which the heart refills with blood after the emptying done during systole (contraction). Ventricular diastole is the period during which the two ventricles are relaxing from the contortions/wringing of contraction, then dilating and filling; atrial diastole is the period during which the two atria likewise are relaxing under suction, dilating, and filling.

The rhythmic contraction of the heart, especially of the ventricles, by which blood is driven through the aorta and pulmonary artery after each dilation or diastole.

(Physiology) The normal rhythmically occurring relaxation and dilatation of the heart chambers, especially the ventricles, during which they fill with blood.

(physiology) The rhythmic contraction of the heart, by which blood is driven through the arteries.

The lengthening of a normally short syllable in Greek and Latin verse.

(prosody) A shortening of a naturally long vowel.

The phase or process of relaxation and dilation of the heart chambers, between contractions, during which they fill with blood; an instance of the process.

(mathematics) The shortest noncontractible loop on a compact metric space.

The lengthening of a vowel or syllable beyond its typical length.

The shortening of the long syllable.

The hypodiastole, a textual or punctuation mark formerly used to disambiguate homonyms in Greek.

The contraction of the heart and arteries by which the blood is forced onward and the circulation kept up; also, the contraction of a rhythmically pulsating contractile vacuole; - correlative to diastole.

The rhythmical expansion or dilatation of the heart and arteries; - correlative to systole, or contraction.

The contraction of the chambers of the heart (especially the ventricles) to drive blood into the aorta and pulmonary artery

A figure by which a syllable naturally short is made long.

The widening of the chambers of the heart between two contractions when the chambers fill with blood