Causes. Blood pressure is a measurement of the pressure in your arteries during the active and resting phases of each heartbeat. Here’s what the numbers mean:
- Systolic pressure. The first (top) number in a blood pressure reading, this is the amount of pressure your heart generates when pumping blood through your arteries to the rest of your body.
- Diastolic pressure. The second (bottom) number in a blood pressure reading, this refers to the amount of pressure in your arteries when your heart is at rest between beats.
Current guidelines identify normal blood pressure as lower than 120/80 mm Hg.