The Difference Between Systolic and Diastolic Blood Pressure
Disclaimer.The materials on this page are intended for informational and educational purposes. No individuals should use the information, resources or tools contained herein to self-diagnosis or self-treat any health-related condition. The content of the website is not meant to be a substitute for advice provided by a doctor or other qualified health care professional. The company will not be held responsible for any negative consequences arising from the use of information posted on this site.
With age, our arteries get a little stiff. As a result, they don't stretch out as much every time the heart beats, so more blood gets pushed right on through the larger vessels into smaller ones. Because there's less blood in the large arteries between heartbeats, diastolic pressure tends to decrease.
High blood pressure or fatty deposits on the walls of the arteries (atherosclerosis) can make your arteries stiff. The greater your pulse pressure, the stiffer and more damaged the blood vessels are thought to be. Treating high blood pressure usually reduces pulse pressure. Following a healthy lifestyle is also important. Heart-smart strategies include getting regular exercise, not smoking, limiting alcohol and reducing the amount of salt in your diet.
The standard blood pressure cuff must be of the proper size to minimize errors in blood pressure determinations. The width of the bladder ideally should be 40% of the circumference of the limb tested. Most standard cuffs have a bladder length that is twice its width. This ensures that the length is the recommended 80% of the limb circumference. Cuffs that are too small give results erroneously high; cuffs that are too large give results erroneously low. The patient should be comfortably seated and the deflated cuff applied with the bladder centered over the brachial artery. It should be high enough on the arm to allow the stethoscope to be placed in the antecubital fossa without touching the cuff. Pressure is then rapidly increased to at least 30 mm Hg higher than that which eliminates a palpable radial pulse (Janeway TC. 1915).
This is true even if you’re taking blood pressure medication. And whether you’ve got high or low blood pressure, tracking your systolic and diastolic numbers is a great way to gauge how well lifestyle changes or medications are working.
Fowler NO. Physiology of cardiac tamponade and pulsus paradoxus. I. Mechanisms of pulsus paradoxus in cardiac tamponade. Mod Concepts Cardiovasc Dis. 1978;47:109–13.
Janeway TC. Important contributions to clinical medicine during the past 30 years from the study of human blood pressure. Bull Johns Hopkins Hosp. 1915;26:341–50.
Kannel WB, Sorlie P. Hypertension in Framingham. In: Paul O, ed. Epidemiology and control of hypertension. New York: Stratton Intercontinental, 1975