systole

systole /sis″təlē/ [Gk, systole, contraction] , the contraction of the heart, driving blood into the aorta and pulmonary arteries. The occurrence of systole is indicated by the first heart sound heard on auscultation, by the palpable apex beat, and by the peripheral pulse. −systolic, adj.

During systole, the heart contracts and blood is pushed out of the heart (Leonard, 2008)