The left ventricle contracts (systole), ejecting blood into the aorta, creating a pressure pulse. This can be measured as the systolic blood pressure. Part of this blood that is ejected during systole remains within the distended arteries, and rebounds during diastole (relaxation of the ventricle), creating the diastolic blood pressure. An adequate blood pressure is required for normal blood flow, however, this does not mean that the presence of a normal arterial blood pressure guarantees that the blood flow is normal. | The left ventricle contracts (systole), ejecting blood into the aorta, creating a pressure pulse. This can be measured as the systolic blood pressure. Part of this blood that is ejected during systole remains within the distended arteries, and rebounds during diastole (relaxation of the ventricle), creating the diastolic blood pressure. An adequate blood pressure is required for normal blood flow, however, this does not mean that the presence of a normal arterial blood pressure guarantees that the blood flow is normal. |