Modern understanding of the cardiovascular system began with the work of physician William Harvey (1578–1657), who described the circulation of blood in his book "De motu cordis". The English clergyman Stephen Hales made the first published measurement of blood pressure in 1733.[152][153] However, hypertension as a clinical entity came into its own with the invention of the cuff-based sphygmomanometer by Scipione Riva-Rocci in 1896.[154] This allowed easy measurement of systolic pressure in the clinic. In 1905, Nikolai Korotkoff improved the technique by describing the Korotkoff sounds that are heard when the artery is ausculated with a stethoscope while the sphygmomanometer cuff is deflated.[153] This permitted systolic and diastolic pressure to be measured.

Blood pressure is measured with a blood pressure cuff (sphygmomanometer). This may be done using a stethoscope and a cuff and gauge or by an automatic machine. It is a routine part of the physical examination and one of the vital signs often recorded for a patient visit. Other vital signs include pulse rate, respiratory rate (breathing rate), temperature, and weight.
^ Jump up to: a b Brook RD, Appel LJ, Rubenfire M, Ogedegbe G, Bisognano JD, Elliott WJ, Fuchs FD, Hughes JW, Lackland DT, Staffileno BA, Townsend RR, Rajagopalan S, American Heart Association Professional Education Committee of the Council for High Blood Pressure Research, Council on Cardiovascular and Stroke Nursing, Council on Epidemiology and Prevention, and Council on Nutrition, Physical, Activity (Jun 2013). "Beyond medications and diet: alternative approaches to lowering blood pressure: a scientific statement from the American Heart Association". Hypertension. 61 (6): 1360–83. doi:10.1161/HYP.0b013e318293645f. PMID 23608661.
^ Mente, Andrew; O'Donnell, Martin; Rangarajan, Sumathy; Dagenais, Gilles; Lear, Scott; McQueen, Matthew; Diaz, Rafael; Avezum, Alvaro; Lopez-Jaramillo, Patricio; Lanas, Fernando; Li, Wei; Lu, Yin; Yi, Sun; Rensheng, Lei; Iqbal, Romaina; Mony, Prem; Yusuf, Rita; Yusoff, Khalid; Szuba, Andrzej; Oguz, Aytekin; Rosengren, Annika; Bahonar, Ahmad; Yusufali, Afzalhussein; Schutte, Aletta Elisabeth; Chifamba, Jephat; Mann, Johannes F E; Anand, Sonia S; Teo, Koon; Yusuf, S (July 2016). "Associations of urinary sodium excretion with cardiovascular events in individuals with and without hypertension: a pooled analysis of data from four studies". The Lancet. 388 (10043): 465–75. doi:10.1016/S0140-6736(16)30467-6. PMID 27216139.
The first chemical for hypertension, sodium thiocyanate, was used in 1900 but had many side effects and was unpopular.[152] Several other agents were developed after the Second World War, the most popular and reasonably effective of which were tetramethylammonium chloride, hexamethonium, hydralazine, and reserpine (derived from the medicinal plant Rauwolfia serpentina). None of these were well tolerated.[159][160] A major breakthrough was achieved with the discovery of the first well-tolerated orally available agents. The first was chlorothiazide, the first thiazide diuretic and developed from the antibiotic sulfanilamide, which became available in 1958.[152][161] Subsequently, beta blockers, calcium channel blockers, angiotensin converting enzyme (ACE) inhibitors, angiotensin receptor blockers, and renin inhibitors were developed as antihypertensive agents.[158]
Moderate or severe bleeding can quickly deplete an individual's body of blood, leading to low blood pressure or orthostatic hypotension. Bleeding can result from trauma, surgical complications, or from gastrointestinal abnormalities such as ulcers, tumors, or diverticulosis. Occasionally, the bleeding may be so severe and rapid (for example, bleeding from a ruptured aortic aneurysm) that it causes shock and death rapidly.
Researchers at the University of Melbourne and Macquarie University have uncovered unusual activity between neurons controlling breathing and blood pressure during the development of essential hypertension. Essential hypertension, which is high blood pressure with no known cause, affects 30% of the global population and is a major contributor to cardiovascular disease.
Strong Heart Study. Since 1988, the NHLBI has supported the Strong Heart Study (SHS), the largest epidemiologic study of American Indians ever conducted. The SHS aims to estimate the impact of heart and blood vessel diseases and to assess how common and significant standard risk factors are in this community. Thirteen tribes and communities in four states participate in the study. Visit Strong Heart Study for more information.

Stress reduction techniques such as biofeedback or transcendental meditation may be considered as an add-on to other treatments to reduce hypertension, but do not have evidence for preventing cardiovascular disease on their own.[125][126][127] Self-monitoring and appointment reminders might support the use of other strategies to improve blood pressure control, but need further evaluation.[128]
Calcium channel blockers are drugs that reduce the movement of calcium into cells of the heart and vessels. This reduces the strength of heart contractions and relaxes the arteries, allowing them to remain more open, lowering blood pressure. Side effects of calcium channel blockers can include heart palpitations, dizziness, swollen ankles, and constipation. Calcium channel blockers can be taken alone or with other blood pressure medications. They should be taken with food or milk. Because of potential interactions, those taking calcium channel blockers should avoid alcohol and grapefruit juice.
Determining the normal blood pressure range in children is a little complicated, and it all depends on the size and age of the child. One rule of thumb that doctors use to determine BP troubles in children is that, a child is considered to be suffering from Prehypertension. If he/she has a blood pressure higher than that of 90% of the children of the same age and size. The child is said to have hypertension if he/she has a blood pressure higher than that of 95% of the children of the same age and size.

How can I stabilize my blood pressure? A wide range of factors influences blood pressure, including anxiety, stress, and medications. High blood pressure can have severe complications, such as a heart attack or stroke. A person can address fluctuating blood pressure with home remedies and lifestyle changes. Learn more about normalizing blood pressure here. Read now

The kidney can respond to changes in blood pressure by increasing or decreasing the amount of urine that is produced. Urine is primarily water that is removed from the blood. When the kidney makes more urine, the amount (volume) of blood that fills the arteries and veins decreases, and this lowers blood pressure. If the kidneys make less urine, the amount of blood that fills the arteries and veins increases and this increases blood pressure. Compared with the other mechanisms for adjusting blood pressure, changes in the production of urine affect blood pressure slowly over hours and days. (The other mechanisms are effective in seconds.)
The primary symptoms of malignant hypertension is a blood pressure of 180/120 or higher and signs of organ damage. Other symptoms of malignant hypertension include bleeding and swelling of blood vessels in the retina, anxiety, nosebleeds, severe headache, and shortness of breath. Malignant hypertension may cause brain swelling, but this symptom is very rare.

As you get older, high blood pressure, especially isolated systolic hypertension, is more common and can increase your risk of serious health problems. Treatment, especially if you have other medical conditions, requires ongoing evaluation and discussions with your doctor to strike the best balance of reducing risks and maintaining a good quality of life.

It has been shown that meditation and other relaxation techniques can help lower blood pressure. Yoga, tai chi, and breathing exercises can also help reduce blood pressure. It's best when these are combined with changes in diet and exercise. Tell your doctor if you are taking any herbal remedies, since some of these preparations can actually raise blood pressure or interact with your blood pressure medications. The following are supplements that may lower blood pressure:
Medications used to lower blood pressure include diuretics (e.g., hydrochlorothiazide*), beta-blockers (e.g., atenolol, metoprolol), ACE inhibitors (e.g., ramipril, enalapril, lisinopril), calcium channel blockers (e.g., nifedipine, amlodipine), angiotensin II receptor blockers (e.g., losartan, valsartan), and direct renin inhibitors (e.g., aliskiren).
Blood pressure is the force of your blood pushing against the walls of your arteries. Each time your heart beats, it pumps out blood into the arteries. Your blood pressure is highest when your heart beats, pumping the blood. This is called systolic pressure. When your heart is at rest, between beats, your blood pressure falls. This is the diastolic pressure. Your blood pressure reading uses these two numbers. Usually they're written one above or before the other, such as 120/80. If your blood pressure reading is 90/60 or lower, you have low blood pressure.