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A pulse pressure (PP) of 21 mmHg indicates that you have NARROW PULSE PRESSURE. It may also be called low pulse pressure in some medical texts.
According to the American Heart Association (AHA) journal Hypertension, a value lesser than 40 mmHg indicates narrow pulse pressure.
However, a publication by S.Y. Liaw, RN, and colleagues in the International Journal of Nursing reports that the exact definition of narrow pulse pressure is not a discrete value but rather a ratio.
According to them, narrow pulse pressure occurs when the pulse pressure drops below 25% of the systolic pressure.
A narrow pulse pressure of 21 mmHg can cause symptoms such as fatigue, dizziness, fainting, shortness of breath, chest pain, and cold limbs.
Major causes of narrow pulse pressure include heart failure, cardiogenic shock, aortic stenosis, hypovolemia (low blood volume), pericardial effusion, and cardiac tamponade.
If you have a consistent pulse pressure reading of 21 mmHg, it can also lead to inadequate blood flow to organs, resulting in compromised oxygen delivery and potential organ dysfunction, contributing to symptoms such as dizziness, weakness, and organ damage.
Addressing comorbidities and adopting a healthy lifestyle to decrease narrow pulse pressure is important. Key strategies you should follow are given below.
- Increasing salt intake moderately
- Staying well-hydrated
- Wearing compression stockings
- Engaging in regular, moderate exercise
- Avoiding prolonged standing or sitting
- Consuming small, frequent meals
- Raising the head of the bed while sleeping
- Monitor and control cholesterol levels
- Regular check-ups
In the following sections, you will learn more about narrow pulse pressure and its health implications in detail.
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Contents
What Is Pulse Pressure?
Pulse pressure is crucial in understanding cardiovascular health, defined as the difference between systolic and diastolic blood pressure readings. Pulse pressure reflects the force the heart generates each time it contracts.
It is a cardiovascular metric that provides insight into the health and elasticity of the arteries, thus serving as an early indicator of cardiovascular diseases.
Since pulse pressure must be read in accordance with other health indicators, it is not a common measurement tool like blood pressure, and there are no official guidelines from AHA, Mayo Clinic, CDC, or WHO.
A 1997 study published in Hypertension by a team of researchers from the State University of New York is by far one of the best references for pulse pressure. According to the study, the various pulse pressure ranges are as follows.
Category | Pulse Pressure (PP) Range |
Low or narrow pulse pressure | PP ≤ 40 mmHg |
Normal pulse pressure | 40 < PP ≤ 50 mmHg |
Elevated pulse pressure | 50 < PP < 65 mmHg |
High or wide pulse pressure | PP ≥ 65 mmHg |
A high pulse pressure indicates a significant drop in pressure between the heart’s contraction and relaxation phases, often pointing to stiffening in the arteries (arteriosclerosis) or other cardiovascular issues, while a low pulse pressure indicates a decrease in stroke volume of blood.
Variations in pulse pressure can occur even minutes apart due to factors like changes in body position, stress, hydration levels, and heart rhythm.
These fluctuations are normal and reflect the dynamic nature of our cardiovascular system responding to different stimuli.
Pulse pressure distinguishes itself from blood pressure, which represents the force exerted by blood flowing through blood vessels against their walls both during and after each heartbeat.
While blood pressure readings consider both the systolic and diastolic pressures to assess overall cardiovascular health, pulse pressure specifically measures the gap between these two, offering additional insights into arterial elasticity and heart function.
Now that you know what pulse pressure is let us learn how to calculate it, and it is very simple! Read more below.
How do you calculate pulse pressure?
Calculating pulse pressure is a simple yet informative process. According to Dr. Francisco Lopez-Jimenez, M.D. from Mayo Clinic, it involves subtracting the diastolic blood pressure from the systolic blood pressure.
Pulse Pressure (PP) = Systolic Blood Pressure (SBP) − Diastolic Blood Pressure (DBP)
The systolic pressure is the top number in a blood pressure reading, indicating the pressure in the arteries when the heart beats.
The diastolic pressure, the bottom number, represents the pressure in the arteries when the heart is at rest between beats.
For example, if someone has a blood pressure reading of 120/80 mmHg, their pulse pressure would be:
PP = 120 − 80 = 40 mmHg
There are no alternative formulas for calculating pulse pressure directly from blood pressure readings.
However, various factors and conditions that influence systolic and diastolic blood pressure can indirectly affect the calculation of pulse pressure.
These include arterial stiffness, blood volume pumped by the heart (stroke volume), the speed at which the pulse wave moves through the circulatory system (pulse wave velocity), and the timing of the reflected waves from the peripheral vasculature.
A deeper understanding of pulse pressure is crucial to monitoring cardiovascular health and identifying potential risks, and below, you will learn more about it.
What does a narrow pulse pressure mean?
According to the Mayo Clinic, a narrow pulse pressure signifies a smaller-than-usual difference between the systolic and diastolic blood pressure readings.
When the pulse pressure narrows, it often reflects a decrease in the volume of blood ejected from the heart with each beat or an increase in resistance to blood flow during the heart’s resting phase between beats.
A pulse pressure of 21 mmHg can be a subtle indicator, suggesting that the heart’s ability to pump blood effectively might be compromised or that there are changes in the elasticity or tone of the arterial walls.
For instance, in a 2020 study published in the American Journal of Surgery, narrow pulse pressure was observed to be an independent indicator for class II hemorrhage.
The heart’s efficiency as a pump ensures oxygen and nutrient delivery throughout the body, and any deviation from optimal functioning can have cascading effects on overall health.
Understanding pulse pressure, particularly when it deviates from the norm, offers insight into the dynamic relationship between the heart’s pumping action and the vascular system’s condition.
While a narrow pulse pressure is a specific metric, its interpretation requires considering the broader context of an individual’s cardiovascular health.
It acts as a piece of the puzzle, contributing to the comprehensive assessment of cardiac function and vascular integrity.
Monitoring and recognizing changes in pulse pressure are crucial steps in safeguarding cardiovascular health, emphasizing the importance of regular health check-ups and cardiovascular assessments.
Identifying narrow pulse pressure at an early stage has a lot of clinical implications, and below are some symptoms that might help you make a quick diagnosis.
What are the symptoms of narrow pulse pressure?
Symptoms associated with a narrow pulse pressure of 21 mmHg may not be immediately obvious, as they can be subtle or indicative of underlying conditions.
According to A 2022 STATPearl publication by Prof. Travis D. Homan and colleagues, below are some of the common symptoms of pulse pressure.
- Fatigue: A common symptom where individuals feel unusually tired or exhausted, potentially due to insufficient blood flow and oxygen delivery to tissues.
- Dizziness or lightheadedness: These feelings may arise due to diminished cardiac output, resulting in decreased blood circulation to the brain.
- Shortness of breath: Experiencing difficulty breathing, especially during physical activity, may indicate that the heart is struggling to pump efficiently.
- Fainting spells (syncope): In certain instances, diminished blood supply to the brain may result in temporary loss of consciousness.
- Palpitations: The feeling of having a fast-beating, fluttering, or pounding heart, possibly reflecting the heart’s effort to maintain adequate blood circulation.
- Cold, clammy skin: This symptom can arise from reduced blood flow to the skin’s surface, making extremities feel colder to the touch.
- Weakness: Generalized weakness may be experienced, stemming from the body’s reduced efficiency in circulating blood and nutrients.
- Swelling of feet and ankles: Fluid accumulation in extremities can be a sign of the heart not pumping blood effectively.
While symptoms are something you can easily identify, knowing the causes of narrow pulse pressure can help rectify the root problems and address them. Keep reading to learn more about the causes.
What are the causes of narrow pulse pressure?
Understanding these causes is vital for diagnosing and managing potential health issues. Having a thorough understanding helps treat the root cause of narrow pulse pressure.
According to a trauma education book titled ‘Advanced Trauma Life Support’ below are some of the most common causes of narrow pulse pressure.
- Cardiac conditions: Reduced heart output due to conditions such as heart failure, where the heart’s ability to pump blood effectively is compromised, can lead to a narrow pulse pressure. Similarly, restrictive cardiomyopathy, which limits the heart’s capacity to fill properly during diastole, can also be a contributing factor.
- Volume status: Hypovolemia, or a decreased volume of circulating blood in the body, whether due to severe dehydration or blood loss, can cause a reduction in pulse pressure. This state affects the amount of blood the heart pumps with each beat.
- Valvular heart disease: Specific valvular conditions, particularly aortic stenosis (narrowing of the aortic valve) and mitral stenosis (narrowing of the mitral valve), can restrict blood flow out of the heart, leading to narrow pulse pressure.
- Increased vascular resistance: Conditions that increase peripheral resistance, such as severe sepsis or shock, can also lead to a narrow pulse pressure by affecting the dynamics between the systolic and diastolic phases of the heart cycle.
- Pericardial diseases: Pericardial effusion (fluid accumulation in the pericardium) and constrictive pericarditis (thickening of the pericardium) can restrict the heart’s ability to expand fully during filling, impacting pulse pressure.
While a pulse pressure of 21 mmHg won’t imply much information to a layman, understanding the risks and associated dangers might help you grasp the gravity of this condition. Read more to learn further.
What are the risks and dangers associated with narrow pulse pressure?
A narrow pulse pressure, marked by a small margin between systolic and diastolic blood pressure measurements, poses numerous risks and hazards, emphasizing the significance of prompt identification and treatment.
One major worry involves the heightened possibility of cardiovascular issues; a narrow pulse pressure of 21 mmHg may suggest diminished cardiac output, which could jeopardize the circulation of oxygen and nutrients to crucial organs, raising the chances of heart attacks and strokes.
This condition can also lead to organ damage, particularly affecting the kidneys, brain, and heart, due to prolonged periods of inadequate blood flow.
For those already dealing with heart conditions such as heart failure or valvular disease, a narrow pulse pressure may exacerbate their symptoms and accelerate the decline in their health status.
In severe cases, especially when associated with acute conditions like sepsis or significant blood loss, a narrow pulse pressure may signal shock, a critical state that demands immediate medical intervention.
Beyond these physical health risks, the symptoms related to narrow pulse pressure, including fatigue and shortness of breath, can severely impact an individual’s daily activities and overall quality of life.
The connection between narrow pulse pressure and these various health risks highlights the necessity for attentive monitoring and proactive management to mitigate its potential adverse effects on an individual’s health.
The current clinical approaches in treating narrow pulse pressure are elaborated below. More about it below.
How is narrow pulse pressure treated?
Treating narrow pulse pressure involves addressing the underlying conditions that contribute to it and implementing strategies to improve the blood flow in various organs.
When it comes to a pulse pressure of 21 mmHg, consider consulting your doctor to be the safer side.
2017 ACC/AHA Guidelines have clearly demonstrated and reported various strategies to manage blood pressure, which is the best way to regulate narrow pulse pressure as well.
The treatment strategy is comprehensive, with the goal of minimizing the chances of cardiovascular complications.
Medications for heart conditions
- Diuretics to reduce fluid overload.
- Beta-blockers to decrease heart rate and improve heart function.
- ACE inhibitors, or ARBs, lower blood pressure and reduce the heart’s workload.
- Inotropic agents to strengthen heart contractions.
Fluid replacement
- For hypovolemia (due to dehydration or blood loss), treatment involves replenishing fluids orally or intravenously to restore proper blood volume.
Treatment for pericardial diseases
- Anti-inflammatory medications for conditions like pericardial effusion.
- Surgical intervention in severe cases of pericardial diseases, such as constrictive pericarditis, to relieve pressure on the heart.
Lifestyle modifications
- Adopting a heart-healthy diet.
- Engaging in regular physical activity.
- Maintaining a healthy weight.
- Avoiding tobacco and excessive alcohol consumption.
Ongoing monitoring and follow-ups
- Regular check-ups with a healthcare provider to monitor the effectiveness of the treatment plan and make adjustments as necessary.
- Consider using top-of-the-line blood pressure monitors like Oxiline Pressure X Pro, CheckMe BP2, Omron Silver, etc for accurate assessment of pulse pressure.
- Referral to a cardiologist or specialist for advanced care in certain cases.
Robin Backlund is a dedicated journalist and a medical student who has written several articles and essays exposing the falseness and hollowness of online resources in the medical science niche.