What Is the Difference Between Systolic and Diastolic Blood Pressure
When people say "taking your blood pressure," they mean measuring the force of the blood that your heart pumps through your body. These two figures are referred to as systolic and diastolic blood pressure, both figures are significant, but for different reasons.
Blood Pressure Overviews
When the heart beats, blood moves through the arteries to get to different parts of the body. is different from what you see from a garden hose or water faucet.
The pulse of the blood flow and the pressure it puts on the body change from time to time. You can tell because it's at its highest point during a heartbeat and at its lowest point between beats (diastolic).
If the readings are too high, it could mean that a person has high blood pressure, which can be dangerous. If the readings are too low, there may not be enough blood moving to the brain and other important parts of the body. It's a sign that there might be a heart condition or other problem
Systolic
By looking at your pulse, you can tell when your heart is beating. This is called a heartbeat, and this is why it is called systole. It's the pressure in your heart during a heartbeat and the highest pressure you can measure.
Systolic Blood Pressure is too High:
When a person is exercising, stressed, or has a high heart rate, the heart muscle pushes out blood with more force. Because of it, the pressure in your heart goes up as well. When there is more pressure, that's normal. In other words, when the pressure is high while a person is at rest, that's called high blood pressure.
Systolic Blood Pressure is too Low:
The term "hypotension" is used when the systolic blood pressure is lower than it should be. If this low blood pressure is bad enough, it can make you lightheaded, dizzy, or faint. If it goes on for a long time and isn't treated, your kidneys may start to shut down, which can be very bad.
Systolic hypotension may happen if there is not enough blood in your body, which can make you feel weak. If you are very thirsty or have a lot of bleeding, this can happen. There isn't enough blood to move through the body.
Diastolic
The heart takes a break between beats so it can get more blood. This pause between beats is called "diastole." During this pause before the next heartbeat, your diastolic blood pressure is the number that is read out.
The diastolic reading, or bottom number, is the pressure in the arteries when the heart is at rest between beats. This is the period during which the heart receives blood and oxygen.
Your diastolic blood pressure reading indicates the following
Less than 80 is considered normal.
For stage 1 hypertension, the range is 80-89.
The diastolic reading, or bottom number, is the pressure in the arteries when the heart is at rest between beats. This is the period during which the heart receives blood and oxygen, having high blood pressure can make your diastolic number go up even when you're just lying down and not moving.
FAQs on Systolic and Diastolic Blood Pressure in the Cardiac Cycle
1. What is systolic and diastolic blood pressure?
Systolic and diastolic blood pressure are the two measurements that represent the pressure of blood in the arteries during and between heartbeats.
Systolic blood pressure is the pressure when the heart ventricles contract and pump blood into the arteries.
Diastolic blood pressure is the pressure when the heart relaxes between beats and fills with blood.
These two values are written as systolic over diastolic, such as 120/80 mmHg.
2. What is the difference between systolic and diastolic blood pressure?
The main difference between systolic and diastolic blood pressure is that systolic measures pressure during heart contraction, while diastolic measures pressure during heart relaxation.
- Systolic pressure: Occurs during ventricular systole (heart contraction).
- Diastolic pressure: Occurs during ventricular diastole (heart relaxation).
- Systolic is usually the higher number in a blood pressure reading.
3. Why is systolic blood pressure higher than diastolic pressure?
Systolic blood pressure is higher because it measures the force exerted when the heart actively pumps blood into the arteries.
- During ventricular contraction, blood is pushed with high force.
- This increases pressure inside the arteries.
- During diastole, the heart relaxes and arterial pressure falls.
4. What is a normal systolic and diastolic blood pressure range?
A normal adult blood pressure is typically around 120/80 mmHg.
- Normal systolic pressure: About 90–120 mmHg.
- Normal diastolic pressure: About 60–80 mmHg.
5. How is systolic and diastolic blood pressure measured?
Systolic and diastolic blood pressure are measured using a sphygmomanometer and a stethoscope or digital monitor.
- A cuff is wrapped around the upper arm.
- The cuff is inflated to stop blood flow in the brachial artery.
- As air is released, the first tapping sound indicates systolic pressure.
- The disappearance of sound indicates diastolic pressure.
6. What happens during systolic blood pressure in the cardiac cycle?
During systolic blood pressure, the ventricles contract and pump blood into the major arteries.
- The left ventricle pumps blood into the aorta.
- The right ventricle pumps blood into the pulmonary artery.
- Arterial pressure rises to its maximum level.
7. What happens during diastolic blood pressure in the cardiac cycle?
During diastolic blood pressure, the heart muscles relax and the chambers fill with blood.
- The ventricles expand during ventricular diastole.
- Blood flows from the atria into the ventricles.
- Arterial pressure drops to its lowest point.
8. Which is more important: systolic or diastolic blood pressure?
Both systolic and diastolic blood pressure are important indicators of cardiovascular health.
- Systolic pressure is often emphasized in adults over 50 as a predictor of heart disease.
- Diastolic pressure is especially important in younger individuals.
- Abnormal levels of either can indicate hypertension or circulatory problems.
9. What causes high systolic or diastolic blood pressure?
High systolic or diastolic blood pressure is usually caused by increased resistance in the arteries or excessive cardiac workload.
- Narrowing of arteries due to atherosclerosis.
- High salt intake and fluid retention.
- Stress and overactivation of the sympathetic nervous system.
- Kidney or endocrine disorders.
10. Why are systolic and diastolic blood pressure important in the body?
Systolic and diastolic blood pressure are important because they ensure proper blood flow and oxygen delivery to tissues.
- Maintain circulation through the systemic and pulmonary circuits.
- Support nutrient and oxygen supply to organs.
- Help remove carbon dioxide and metabolic wastes.
