Dr. Shiel received a Bachelor of Science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his Internal Medicine residency and Rheumatology fellowship at the University of California, Irvine. He is board-certified in Internal Medicine and Rheumatology.


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An abnormally fast heart rate (tachycardia) also can cause low blood pressure. The most common example of tachycardia causing low blood pressure is atrial fibrillation (Afib). Atrial fibrillation is a disorder of the heart characterized by rapid and irregular electrical discharges from the muscle of the heart causing the ventricles to contract irregularly and (usually) rapidly. The rapidly contracting ventricles do not have enough time to fill maximally with blood before each contraction, and the amount of blood that is pumped decreases in spite of the faster heart rate. Other abnormally rapid heart rhythms such as ventricular tachycardia also can produce low blood pressure, and sometimes life-threatening shock.
Hypertension results from a complex interaction of genes and environmental factors. Numerous common genetic variants with small effects on blood pressure have been identified[34] as well as some rare genetic variants with large effects on blood pressure.[35] Also, genome-wide association studies (GWAS) have identified 35 genetic loci related to blood pressure; 12 of these genetic loci influencing blood pressure were newly found.[36] Sentinel SNP for each new genetic locus identified has shown an association with DNA methylation at multiple nearby CpG sites. These sentinel SNP are located within genes related to vascular smooth muscle and renal function. DNA methylation might affect in some way linking common genetic variation to multiple phenotypes even though mechanisms underlying these associations are not understood. Single variant test performed in this study for the 35 sentinel SNP (known and new) showed that genetic variants singly or in aggregate contribute to risk of clinical phenotypes related to high blood pressure.[36]
An elevated blood pressure reading means that your blood pressure falls just above the normal level, corresponding to a systolic pressure between 120 and 129 or a diastolic pressure of 80 or less. The new guidelines eliminate the previous category of prehypertension. About one-fourth of Americans have elevated levels and they have two times the risk of heart disease compared with those who have lower blood pressures. Lifestyle changes can help many people with prehypertension lower their blood pressure.
High blood pressure is the most common chronic medical problem prompting visits to primary health care providers in USA. The American Heart Association estimated the direct and indirect costs of high blood pressure in 2010 as $76.6 billion.[144] In the US 80% of people with hypertension are aware of their condition, 71% take some antihypertensive medication, but only 48% of people aware that they have hypertension adequately control it.[144] Adequate management of hypertension can be hampered by inadequacies in the diagnosis, treatment, or control of high blood pressure.[164] Health care providers face many obstacles to achieving blood pressure control, including resistance to taking multiple medications to reach blood pressure goals. People also face the challenges of adhering to medicine schedules and making lifestyle changes. Nonetheless, the achievement of blood pressure goals is possible, and most importantly, lowering blood pressure significantly reduces the risk of death due to heart disease and stroke, the development of other debilitating conditions, and the cost associated with advanced medical care.[165][166]
Dr. Charles "Pat" Davis, MD, PhD, is a board certified Emergency Medicine doctor who currently practices as a consultant and staff member for hospitals. He has a PhD in Microbiology (UT at Austin), and the MD (Univ. Texas Medical Branch, Galveston). He is a Clinical Professor (retired) in the Division of Emergency Medicine, UT Health Science Center at San Antonio, and has been the Chief of Emergency Medicine at UT Medical Branch and at UTHSCSA with over 250 publications.
If diet and exercise are not sufficient to lower blood pressure, the first medications recommended are often diuretics or so-called "water pills." These reduce sodium and fluid levels in the body to lower blood pressure. Taking diuretics means you will urinate more frequently. Sometimes, diuretics deplete potassium levels as well, which can lead to muscle weakness, leg cramps, and tiredness. Other side effects of diuretics can include elevated blood sugars in people with diabetes. Less commonly, erectile dysfunction can occur.
This study is exploring whether use of losartan, a medicine commonly used to lower blood pressure, is effective at treating abnormal nighttime blood pressure in children and young adults who have sickle cell disease. To participate in this study, you or your child must be 5 to 25 years old and have high blood pressure and a certain type of sickle cell disease: hemoglobin SS or Sβ0 thalassemia. This study is located in Birmingham, Alabama.
Effective lifestyle modification may lower blood pressure as much as an individual antihypertensive medication. Combinations of two or more lifestyle modifications can achieve even better results.[87] There is considerable evidence that reducing dietary salt intake lowers blood pressure, but whether this translates into a reduction in mortality and cardiovascular disease remains uncertain.[96] Estimated sodium intake ≥6g/day and <3g/day are both associated with high risk of death or major cardiovascular disease, but the association between high sodium intake and adverse outcomes is only observed in people with hypertension.[97] Consequently, in the absence of results from randomized controlled trials, the wisdom of reducing levels of dietary salt intake below 3g/day has been questioned.[96]
Right after exercise is stopped, blood pressure decreases — often to levels a bit lower than normal resting blood pressure, and this effect can last for hours. Also, people who exercise regularly usually experience permanent improvements in resting blood pressure levels, as exercise strengthens the heart, helps with weight loss, improves circulation and lessens peripheral resistance — all factors that benefit blood pressure.
Echocardiogram is an ultrasound examination of the heart It is used to evaluate the anatomy and the function of the heart. A cardiologist is required to interpret this test and can evaluate the heart muscle and determine how thick it is, whether it moves appropriately, and how efficiently it can push blood out to the rest of the body. The echocardiogram can also assess heart valves, looking for narrowing (stenosis) and leaking (insufficiency or regurgitation). A chest X-ray may be used as a screening test to look for heart size, the shape of the aorta, and to assess the lungs.
2. Take the right nutrients. Talk with your chiropractor or other healthcare professional about the wide range of well-studied nutrients that, along with dietary and lifestyle modifications, can help normalize your blood pressure. One meta-analysis found magnesium supplements could lower blood pressure. Likewise, researchers find a small but significant decline in blood pressure for people with hypertension who use fish oil. (You can get all of fish oil’s benefits combined with anti-inflammatory flax oil and GLA in our Optimal Omega.) 
Some people may ask why doctors are lowering the threshold for high blood pressure, when it was already difficult for many patients to achieve the previous blood pressure targets of below 140 mm Hg/90 mm Hg, said Dr. Pamela B. Morris, a preventive cardiologist and chairwoman of the ACC's Prevention of Cardiovascular Disease Leadership Council. However, Morris said that the guidelines were changed because "we now have more precise estimates of the risk of [high] blood pressures," and these new guidelines really communicate that risk to patients. So, just because it's going to be difficult for people to achieve, "I don't think it's a reason not to communicate the risk to patients, and to empower them to make appropriate lifestyle modifications," Morris told Live Science.

Sodium is a key part of how the body controls blood pressure levels. The kidneys help balance fluid and sodium levels in the body. They use sodium and potassium to remove excess fluid from the blood. The body gets rid of this excess fluid as urine. When sodium levels in the blood are high, blood vessels retain more fluid. This increases blood pressure against the blood vessel walls.
MRI (or magnetic resonance imaging) scan is a radiology technique which uses magnetism, radio waves, and a computer to produce images of body structures. MRI scanning is painless and does not involve X-ray radiation. Patients with heart pacemakers, metal implants, or metal chips or clips in or around the eyes cannot be scanned with MRI because of the effect of the magnet.
Healthcare professionals use a stethoscope and a manual sphygmomanometer to measure your blood pressure. Typically they take the reading above your elbow. The sphygmomanometer has a bladder, cuff, bulb, and a gauge. When the bulb is pumped it inflates the bladder inside the cuff, which is wrapped around your arm. This inflation will stop the blood flow in your arteries. The stethoscope is used to listen for sound of the heartbeat, and no sound indicates that there is no flow. As the pressure is released from the bladder, you will hear the sound of the blood flowing again. That point becomes systolic reading. The diastolic reading is when you hear no sound again, which means that the blood flow is back to normal.
About This Image: Person receiving a blood pressure test. Medical research shows that as we age blood pressure rises slightly to accommodate an increased demand of oxygen and nutrients. It is completely natural for the first number (systolic) to be 100 plus our age. A recent study by a group of UCLA researchers came very close to corroborating Dr. Piette's guide for blood pressure of 100 plus your age for men, subtracting 10 for women, and this is after this rule had been in use for five or more decades. Are we now being taught that Dr. Piette's guide for blood pressure is wrong merely for drug company profit?
There was a time when the high blood pressure medication list was very short indeed. In the 1950s, reserpine was one of the few products on the market to treat hypertension. It is rarely used due to its numerous side effects and drug interactions. The peripheral adrenergic inhibitors work in the brain to block signals that tell blood vessels to constrict. They are mostly used when other high blood pressure medications fail to solve the problem. Guanadrel (Hylorel), guanethidine monosulfate (Ismelin), and reserpine (Serpasil) are peripheral adrenergic inhibitors.
In hypertensive emergency, there is evidence of direct damage to one or more organs.[27][28] The most affected organs include the brain, kidney, heart and lungs, producing symptoms which may include confusion, drowsiness, chest pain and breathlessness.[26] In hypertensive emergency, the blood pressure must be reduced more rapidly to stop ongoing organ damage,[26] however, there is a lack of randomized controlled trial evidence for this approach.[28]
Hypertension is rarely accompanied by symptoms, and its identification is usually through screening, or when seeking healthcare for an unrelated problem. Some people with high blood pressure report headaches (particularly at the back of the head and in the morning), as well as lightheadedness, vertigo, tinnitus (buzzing or hissing in the ears), altered vision or fainting episodes.[20] These symptoms, however, might be related to associated anxiety rather than the high blood pressure itself.[21]
Unfortunately, a problem doesn’t always announce itself with a fanfare of trumpets. Even the highest blood pressure can be entirely asymptomatic. Similarly, low blood pressure also known as hypotension can occur in your patient despite no symptoms seemingly being present. This is particularly true if the patient is lying still in an unmonitored bed.

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.
Some people have low blood pressure all the time. They have no symptoms and their low readings are normal for them. In other people, blood pressure drops below normal because of a medical condition or certain medicines. Some people may have symptoms of low blood pressure when standing up too quickly. Low blood pressure is a problem only if it causes dizziness, fainting or in extreme cases, shock.
Vasovagal syncope can be treated with several types of drugs such as beta blockers, for example, propanolol (Inderal, Inderal LA) and selective serotonin reuptake inhibitors such as fluoxetine (Prozac), escitalopram oxalate (Lexapro), paroxetine (Paxil), sertraline (Zoloft), citalopram (Celexa), and fluvoxamine (Luvox). Fludrocortisone (Florinef) (a drug that prevents dehydration by causing the kidney(s) to retain water) also may be used. A pacemaker can also be helpful when a patient fails drug therapy.

^ 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.


Hypertension is diagnosed on the basis of a persistently high resting blood pressure. The American Heart Association recommends at least three resting measurements on at least two separate health care visits.[74] The UK National Institute for Health and Care Excellence recommends ambulatory blood pressure monitoring to confirm the diagnosis of hypertension if a clinic blood pressure is 140/90 mmHg or higher.[75]
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