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Systolic and Diastolic Blood Pressure

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Systolic and Diastolic Blood Pressure

Systolic and Diastolic Blood Pressure

Systolic blood pressure refers to the pressure of blood in the artery when the heart contracts. It is the top (and higher) number in a blood pressure reading.

Diastolic blood pressure refers to the pressure of blood in the artery when the heart relaxes between beats. It is the bottom (and lower) number in a blood pressure reading.

For example, if a person's systolic pressure is 120 millimeters of mercury (mm Hg) and the diastolic pressure is 80 mm Hg, blood pressure is recorded as 120/80 and read as "120 over 80."