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Blood pressure measurements include both a systolic and a diastolic reading. These two readings are taken at opposite ends of the cardiac cycle and are a person's highest and lowest blood pressure levels. The difference between these two extremes is called the pulse pressure, and represents the force that your heart generates each time it contracts. In a person with a systolic blood pressure of 120 mmHg and a diastolic pressure of 80 mmHg, the pulse pressure would be 40 mmHg.
Some evidence suggests that pulse pressure is a better predictor of clinical outcome than the systolic or diastolic blood pressure alone. However, using pulse pressure as a clinical predictor or diagnosis tool is complicated because the pulse pressure doesn’t provide unique information. Pulse pressure must be calculated from the systolic and diastolic readings. So, saying that someone has an “elevated pulse pressure” is usually the same as saying that they have an “elevated systolic blood pressure,” which is already known to be an important clinical finding requiring treatment.
A person with normal blood pressure(120/80) will have a pulse pressure of 40 (120-80). But that doesn’t mean that a person with a pulse pressure of 40 has normal blood pressure. Consider these examples:
- Systolic Pressure = 120; Diastolic Pressure = 80; Pulse Pressure = 120-80 = 40
- Systolic Pressure = 140; Diastolic Pressure = 100; Pulse Pressure = 140-100 = 40
Clearly, a blood pressure of 140/100 is much different than 120/80. These examples demonstrate that pulse pressure, by itself, can’t be used to make treatment decisions when other information is unavailable.
Sometimes pulse pressure does provide important information. A number of studies have shown that pulse pressure does offer value when thinking about a patient’s overall risk profile. Several studies have identified that high pulse pressure:
- Causes more artery damage compared to high blood pressure with normal pulse pressure
- Indicates elevated stress on a part of the heart called the left ventricle
- Is affected differently by different high blood pressure medicines
While pulse pressure generally won’t change your course of treatment, your doctor may consider it when designing your overall treatment plan.
O' Rourke, M, et al. Pulse Pressure: Is this a clinically useful risk factor? Hypertension, 1999; 34:372.
Franklin, SS, et al. Is pulse pressure useful in predicting risk for coronary heart disease? The Framingham heart study. Circulation, 1999 July 27; 100(4):354-60.
Vaccarino, V, et al. Pulse pressure and risk of cardiac events in the Systolic Hypertenion in the Elderly (SHE) program. American Journal of Cardiology, 2001 Nov 1; 88(9):980-6.
Domanski, MJ, et al. Isolated systolic hypertension: Prognostic information provided by pulse pressure. Hypertension, 1999 Sep; 34(3):375-80.Pulse pressure: An indicator of heart health? What is pulse pressure? How important is pulse pressure to your overall health? Answer from Sheldon G. Sheps, M.D.
Blood pressure readings are given in two numbers. The top number is the maximum pressure your heart exerts while beating (systolic pressure), and the bottom number is the amount of pressure in your arteries between beats (diastolic pressure). The numeric difference between your systolic and diastolic blood pressure is called your pulse pressure. For example, if your resting blood pressure is 120/80 millimeters of mercury (mm Hg), your pulse pressure is 40 — which is considered a normal and healthy pulse pressure.
A high pulse pressure may be a strong predictor of heart problems, especially for older adults. Generally, a pulse pressure greater than 40 mm Hg is abnormal. A pulse pressure lower than 40 may mean you have poor heart function, while a higher pulse pressure may mean your heart's valves are leaky (valve regurgitation).
The most important cause of elevated pulse pressure is stiffness of the aorta, the largest artery in the body. The stiffness may be due to high blood pressure or fatty deposits on the walls of the arteries (atherosclerosis). The greater your pulse pressure, the stiffer and more damaged the vessels are thought to be. Other conditions — including severe iron deficiency (anemia) and overactive thyroid (hyperthyroidism) — can increase pulse pressure as well.
Treating high blood pressure usually reduces pulse pressure as well.