Why Is Systolic Pressure Higher Than Diastolic Pressure?

Blood pressure is used as an indicator for general health and potential risk of heart disease, stroke and other cardiovascular problems. A reading consists of a higher number, systolic pressure, over a lower number, or diastolic pressure.

Systolic Pressure

When the heart contracts to circulate blood throughout the body, it is called systole. There is increased pressure against the arterial walls as this greater volume of blood is pushed through, like water flowing through a garden hose.

Diastolic Pressure

After a contraction, the heart relaxes and fills with blood, going into diastole. This decreases pressure against the artery walls, created by the heart only fractions of a second ago.

Elevated Readings

Individuals with systolic blood pressure over 120 mm Hg (millimeters of mercury) or diastolic blood pressure over 80 mm Hg, are considered higher risk for vascular disorders.

Relative Importance

Traditionally, a high diastolic pressure has caused slightly more concern because this is when the heart should be at its most relaxed. However, there is evidence that systolic pressure is a better indicator of mortality risk.

Healthy Pressure

Regular exercise, decreasing stress levels, and proper eating habits are a few ways to keep blood pressure in check. For others, medication may also be necessary to reduce their risk of disease.

References

• Systolic Blood Pressure, Diastolic Blood Pressure, and Pulse Pressure: An Evaluation of Their Joint Effect on Mortality

Resources

• What Are High Blood Pressure and Prehypertension?
• Blood Pressure