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.
In some cases, when plaque ruptures, a blood clot may block blood supply to the heart muscle. This causes a heart attack. If a blood vessel to the brain is blocked, usually from a blood clot, an ischemic stroke can happen. If a blood vessel within the brain bursts, most likely as a result of uncontrolled hypertension (high blood pressure), a hemorrhagic stroke can result.