diastolic blood pressure

physiology

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July 23, 2026

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Diastolic blood pressure is the residual pressure in the arteries when the heart relaxes between beats. It is the lower number recorded when measuring blood pressure, typically around 80 millimeters of mercury (mmHg) in healthy individuals. This pressure is a key component of the cardiac cycle, occurring during the heart muscle's relaxation phase, known as diastole.12

Diastole is crucial for allowing the heart chambers to fill with blood. While systolic pressure reflects the force of blood against artery walls during heart contraction, diastolic pressure indicates the minimum pressure exerted on the arteries during the heart's resting phase. Abnormally low diastolic pressure can lead to dizziness and fainting, while consistently high diastolic pressure is a component of hypertension.21

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Hypertensive disorders of pregnancy
…Hg) or higher and a diastolic blood pressure of 90 mm Hg or higher, which antedate pregnancy. (The systolic is the highest blood pressure after the heart has contracted; the diastolic, the lowest after the heart has expanded.) An elevated blood pressure that first develops during pregnancy and persists beyond…
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…Hg) or higher and a diastolic blood pressure of 90 mm Hg or higher, which antedate pregnancy. (The systolic is the highest blood pressure after the heart has contracted; the diastolic, the lowest after the heart has expanded.) An elevated blood pressure that first develops during pregnancy and persists beyond…
Read More