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.

A hypertensive emergency, unlike the similar sounding hypertensive urgency, is characterized by serious, life-threatening complications. A hypertensive emergency means that the blood pressure is >180 mm Hg or the diastolic pressure is >120 mm Hg, and that end-organ damage is occurring. Signs and symptoms can include shortness of breath, anxiety, chest pain, irregular heart rate, confusion, or fainting.  

Meschia JF, Bushnell C, Boden-Albala B, et al; American Heart Association Stroke Council; Council on Cardiovascular and Stroke Nursing; Council on Clinical Cardiology; Council on Functional Genomics and Translational Biology; Council on Hypertension.. Guidelines for the primary prevention of stroke: a statement for healthcare professionals from the American Heart Association/American Stroke Association. Stroke. 2014;45(12):3754-3832. PMID: 25355838 www.ncbi.nlm.nih.gov/pubmed/25355838.

Most commonly high blood pressure causes no symptoms at all. This means that people with high blood pressure can be having damage occur to their heart, kidneys, eyes, and circulation without feeling badly! It is very important, therefore, to have blood pressure testing as part of the routine physical examination. However, in people with uncomplicated high blood pressure, they may experience

A reduction from 8% to 6% of cardiovascular events is known as an absolute risk reduction of 2%. This may seem small, but the translation is not small when applied to real world people. This can be understood more easily as something called “number needed to treat” which is calculated by 1 divided by the absolute risk reduction. In this case, an absolute risk reduction of 2% translates to a “number needed to treat” of 50 (1 divided by 0.02 = 50). This means that 50 people need to have a BP down to < 120/80 in order for 1 cardiovascular event to be prevented. In the context of many other things we do in our life (medical treatment or not), this is really good!
^ Jump up to: a b c Giuseppe, Mancia; Fagard, R; Narkiewicz, K; Redon, J; Zanchetti, A; Bohm, M; Christiaens, T; Cifkova, R; De Backer, G; Dominiczak, A; Galderisi, M; Grobbee, DE; Jaarsma, T; Kirchhof, P; Kjeldsen, SE; Laurent, S; Manolis, AJ; Nilsson, PM; Ruilope, LM; Schmieder, RE; Sirnes, PA; Sleight, P; Viigimaa, M; Waeber, B; Zannad, F; Redon, J; Dominiczak, A; Narkiewicz, K; Nilsson, PM; et al. (July 2013). "2013 ESH/ESC Guidelines for the management of arterial hypertension: The Task Force for the management of arterial hypertension of the European Society of Hypertension (ESH) and of the European Society of Cardiology (ESC)". European Heart Journal. 34 (28): 2159–219. doi:10.1093/eurheartj/eht151. PMID 23771844.
Low blood pressure is diagnosed by a doctor when they check your blood pressure with a sphygmomanometer. For people who experience low blood pressure without other symptoms, it may only require regular monitoring by a doctor during routine exams, and medical treatment may not be necessary. If certain signs suggest an underlying condition, your doctor may recommend one or more of the following tests to diagnose a cause for your hypotension:
Low blood pressure is also known as hypotension. This is usually defined in an adult as a systolic recording of less than 90 mmHg, although it has been suggested that for elderly people, below 110 mmHg is a more appropriate definition. Blood pressure and heart rate are controlled by the autonomic nervous system (the nervous system that controls bodily functions that we do not have to think about).                                                                                                                                                                                                
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.
^ Jump up to: a b c d e f Chobanian AV, Bakris GL, Black HR, Cushman WC, Green LA, Izzo Jr. JL, Jones DW, Materson BJ, Oparil S, Wright Jr. JT, Roccella EJ, et al. (December 2003). "Seventh report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure". Hypertension. Joint National Committee On Prevention. 42 (6): 1206–52. doi:10.1161/01.HYP.0000107251.49515.c2. PMID 14656957. Archived from the original on 20 May 2012. Retrieved 1 January 2012.

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.
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]

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.

Certain medications contain ingredients that can elevate blood pressure. Cold and flu medications that contain decongestants are one example of drugs that raise blood pressure. Other kinds of medicines that can raise blood pressure are steroids, diet pills, birth control pills, non-steroidal anti-inflammatory drugs (NSAIDs), pain relief medications, and some antidepressants. Talk to your doctor about the medications or supplements you are taking that might affect your blood pressure.

Medicines are available if these changes do not help control your blood pressure within 3 to 6 months. Diuretics help rid your body of water and sodium. ACE inhibitors block the enzyme that raises your blood pressure. Other types of medicines— beta blockers, calcium channel blockers, and other vasodilators—work in different ways, but their overall effect is to help relax and widen your blood vessels and reduce the pressure inside the vessel. [See also the free government publication “Medicines to Help You: High Blood Pressure” (PDF) from the US Food and Drug Administration.]
Postural hypotension is considered to be a failure of a person's cardiovascular system or nervous system to react appropriately to sudden changes. Usually, when a person stands up, some of their blood pools in their lower extremities. If this remains uncorrected, it would cause the person's blood pressure to fall or decrease. A person's body usually compensates by sending messages to their heart to beat faster and to their blood vessels to constrict, offsetting the drop in blood pressure. If this does not happen, or does not happen quickly enough, postural hypotension is the result.
Cirrhosis of the liver is the most common cause of portal hypertension. In cirrhosis, the scar tissue (from the healing of liver injury caused by hepatitis, alcohol, or other liver damage) blocks the flow of blood through the liver. Blood clots in the portal vein, blockages of the veins that carry blood from the liver to the heart, parasitic infection (schistosomiasis), and focal nodular hyperplasia are also causes of portal hypertension.
One especially important cause of low blood pressure is orthostatic hypotension, which is sometimes referred to as postural hypotension. This happens when blood pressure drops rapidly during changes in body position—usually when changing from sitting to standing—inducing classic signs that the blood pressure is too low, like dizziness, blurry vision, and fainting.
Orthostasis literally means standing upright. Orthostatic hypotension, or postural hypotension, is defined as a decrease in systolic blood pressure of at least 20 mm Hg or at least 10mm Hg within 3 minutes of the patient standing. If orthostatic hypotension is present, the client may be at risk of falls and should be closely supervised with ambulation or advised to call for assistance with activity.
Caffeine can bring on the jitters, but there is no evidence that it can cause long-term hypertension. However, a caffeinated beverage might bring on a temporary rise in blood pressure. It is possible that caffeine could block a hormone that helps keep arteries widened, which causes blood pressure to rise. It is also possible that caffeine causes adrenal glands to release more adrenaline, causing blood pressure to increase. The exact reason why caffeine causes increased blood pressure is unknown.
Normal blood pressure is less than 120/80. Knowing your blood pressure and remembering to check it regularly can help save your life. Choosing healthier, heart-conscious foods, maintaining a healthy weight, getting up and staying active, and managing your stress are great ways to help keep your blood pressure at the level it should be. Learn more about what you can do to help control your blood pressure.
For a normal reading, your blood pressure needs to show a top number (systolic pressure) that’s between 90 and less than 120 and a bottom number (diastolic pressure) that’s between 60 and less than 80. The American Heart Association (AHA) considers blood pressure to be within the normal range when both your systolic and diastolic numbers are in these ranges.
Dietary changes can help control blood pressure. One diet designed to promote lower blood pressure is known as the DASH diet. This stands for Dietary Approaches to Stop Hypertension. The DASH diet recommends eating more vegetables, fruits, whole grains, low-fat dairy products, poultry, nuts, and fish. Red meat, saturated fats, and sweets should be avoided. The DASH diet can lower blood pressure within 2 weeks. It can also help to reduce your intake of sodium. The following is the DASH diet suggested daily intake:
In the 19th and 20th centuries, before effective pharmacological treatment for hypertension became possible, three treatment modalities were used, all with numerous side-effects: strict sodium restriction (for example the rice diet[152]), sympathectomy (surgical ablation of parts of the sympathetic nervous system), and pyrogen therapy (injection of substances that caused a fever, indirectly reducing blood pressure).[152][158]
There is no treatment available for the causes of portal hypertension. However, treatment can prevent or manage the complications. Diet, medication (nonselective beta-blockers), endoscopic therapy, surgery, and radiology procedures can all help in treating or preventing symptoms of portal hypertension. If these treatments are unsuccessful in treating symptoms, transjugular intrahepatic portosystemic shunt (TIPS) or distal splenorenal shunt (DSRA) are two procedures that may reduce pressure in the portal veins. Maintaining a healthy lifestyle may help to prevent portal hypertension.