Pulse pressure is a term used to describe the different between diastolic and systolic blood pressure.
The force exerted by blood on the blood vessel walls is referred to as blood pressure. It is calculated by finding the force exerted by the circulating blood on the blood vessel walls during systole and diastole, which are the two stages of the heart cycle. The heart/cardiac cycle is a term used to describe the series of events that occur during the course of heart beats. Diastole and systole are the 2 stages of this activity of the heart.The pressure that blood exerts during a systole and a diastole is respectively called systolic blood pressure and diastolic blood pressure. Doctors refer to the difference between these two types of blood pressure as pulse pressure.
Clinical significance of pulse pressure
Blood pressure readings in adults that is at 120/80 mmHg is regarded as normal. Thus healthy people with a diastolic blood pressure of 80 mmHg and a systolic blood pressure of 120 mmHg feature a pulse pressure of 40 mmHg. This reading tends to differ in people with irregular blood pressure.
Diastolic pressure refers to the pressure that the blood exerts during the stage of diastole, i.e., relaxation of the heart and it getting filled with blood.Systolic pressure is the pressure that the blood exerts during systole phase of cardiac activity, i.e., contraction of the heart muscle and pumping of blood.
Low pulse pressure or narrow pulse pressure is a term used to describe the condition of excessive reduction of the difference between the diastolic and systolic blood pressure. A pulse pressure of under 25 is regarded to be very low. It may also be noted that variations may occur in the readings of healthy people after they engage in some vigorous exercising or physical activities; but in such cases, the pulse pressure comes back to normal after the passage of some time.
Resting pulse pressure is the difference between the diastolic and systolic blood pressure when a person is relaxed, not engaging in any kind of exerting physical activity, or sitting. This pressure should not be too high or too low. People with low pulse pressure for prolonged periods need to consult a doctor as it could occur due to a variety of severe health disorders.
It is also important to remember that abnormal or low pulse pressure should not be the only factor that is taken into consideration when trying to diagnose any underlying health problem. This is because of the fact that a healthy individual with the perfect blood pressure of 120/80 mmHg will have the same pulse pressure reading of 40 when compared to an individual with an abnormal blood pressure reading of 140/100 mmHg.
Causes of low pulse pressure
In most cases, any kind of reduction in the systolic pressure or any increase in diastolic pressure may trigger a case of low pulse pressure. Some health conditions that cause abnormal blood pressure as a symptom may also lead to low pulse pressure. The symptoms that accompany low pulse pressure tend to differ as per the severity of the health disorder that affects the blood pressure.
Some of the common causes of low pulse pressure are listed below:
- Low volume of blood because of some injury can result in hypovolemic shock, thereby causing low pulse pressure readings.
- The readings can also be affected by mitral valve constriction; it is the valve present between the left ventricle and the left atrium. A narrow mitral valve will prevent or hamper the free flow of blood from the left atrium to the left ventricle at the time of a cardiac diastole. This can cause buildup of blood in the left atrium, which can then trigger an increase in the diastolic blood pressure.
- Aortic valve constriction can trigger a case of aortic stenosis. This valve regulates the passage of blood from the left ventricle to the aorta as well as to other areas of the body. Narrowing of this valve may prevent the passage of adequate amounts of blood out of the left ventricle during a cardiac systole. This can then lower the aortic pressure at the time of systole, thereby causing low pulse pressure.
- Other medical conditions that may cause low pulse pressure include:
- Cardiac tamponade, i.e., cardiac compression because of blood deposition in the space between the pericardium and the cardiac muscle.
- Pericardial effusion, i.e., excessive fluid buildup in the pericardial cavity.
- Constrictive pericarditis, i.e., prolonged pericardium inflammation marked by elasticity loss and scarring of the pericardium.
- Tachycardia, i.e., abnormally quick heartbeat
- Ascites, i.e., fluid accumulation in the peritoneal cavity
Treatment of low pulse pressure
Low pulse pressure is a symptom of poor cardiac function. Hence, it is important to visit a doctor for diagnosis and relevant treatment.
Treatment of low pulse pressure is dependent on the cause. If it is caused due to minor illnesses, then it can be easily treated with medications. Hospitalization may be required for treatment of causative conditions like valve disorders, shock,cardiac tamponade, heart attack, or congestive heart failure, etc.
Eating a healthy and balanced diet, lifestyle changes, exercising, and managing stress can also help normalize low pulse pressure.
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