- The time period when the heart is contracting. The period specifically during which the left ventricle of the heart contracts. The final letter in "systole" is pronounced as a long "e" as in "lee." The adjective for systole is systolic. The systolic pressure is specifically the maximum arterial pressure during contraction of the left ventricle of the heart. In a blood pressure reading, the systolic pressure is typically the first number recorded. For example, with a blood pressure of 120/80 ("120 over 80"), the systolic pressure is 120. By "120" is meant 120 mm Hg (millimeters of mercury). A systolic murmur is a heart murmur heard during systole, the time the heart contracts, between the normal first and second heart sounds. "Systole" came without change from the Greek systole meaning "a drawing together or a contraction." The term has been in use since the 16th century to denote the contraction of the heart muscle.
* * *Contraction of the heart, especially of the ventricles, by which the blood is driven through the aorta and pulmonary artery to traverse the systemic and pulmonary circulations, respectively; its occurrence is indicated physically by the first sound of the heart heard on auscultation, by the palpable apex beat, and by the arterial pulse. [G. s., a contracting]- aborted s. a loss of the systolic beat in the radial pulse through weakness of the ventricular contraction.- electrical s. the duration of the QRST complex ( i.e., from the earliest Q wave to the end of the latest T wave on the ECG).- electromechanical s. the period from the beginning of the QRS complex to the first (aortic) vibration of the second heart sound. SYN: QS2 interval.- late s. SYN: prediastole.
* * *sys·to·le 'sis-tə-(.)lē n the contraction of the heart by which the blood is forced onward and the circulation kept up compare DIASTOLE (1)sys·tol·ic sis-'täl-ik adj
* * *n.the period of the cardiac cycle during which the heart contracts. The term usually refers to ventricular systole, which lasts about 0.3 seconds. Atrial systole lasts about 0.1 seconds.• systolic adj.
* * *sys·to·le (sisґto-le) [Gr. systolē a drawing together, contraction] the contraction, or period of contraction, of the heart, especially that of the ventricles; sometimes divided into components, as preejection and ejection periods, or isovolumic and ejection.
Medical dictionary. 2011.