ERA. 1  baseball, baseball game - a ball game played with a bat and ball between two teams of nine players; teams take turns at bat trying to score runs; he played baseball in high school; there was a baseball game on every empty lot; there was a desire for National League ball in the area; play ball!.
The contraction of the heart muscle starts in the two atria, which push the blood into the ventricles. Then the walls of the ventricles squeeze together and force the blood out into the arteries: the aorta to the body and the pulmonary artery to the lungs.
High blood pressure makes your heart worker harder than it needed to before. Over the space of many years, this extra effort can lead to the heart muscle becoming thicker and less effective at pushing the blood round. This allows fluid to build up in your lower legs and ankles, which causes them to swell up.