The heart pumps blood into the arteries with enough force to push blood to the far reaches of each organ from the top of the head to the bottom of the feet. Blood pressure can be defined as the pressure of blood on the walls of the arteries as it circulates through the body. Blood pressure is highest as its leaves the heart through the aorta and gradually decreases as it enters smaller and smaller blood vessels (arteries, arterioles, and capillaries). Blood returns in the veins leading to the heart, aided by gravity and muscle contraction.
Hypertension is the medical term for high blood pressure. It is known as the "silent killer" since it has no initial symptoms but can lead to long-term disease and complications..
Many people have high blood pressure and don't know it.
Important complications of uncontrolled or poorly treated high blood pressure include heart attack, congestive heart failure, stroke, kidney failure, peripheral artery disease, and aortic aneurysms (weakening of the wall of the aorta, leading to widening or ballooning of the aorta).
How is blood pressure measured?
Blood pressure is measured with a blood pressure cuff and recorded as two numbers, for example, 120/80 mm Hg (millimeters of mercury). Blood pressure measurements are usually taken at the upper arm over the brachial artery.
The top, larger number is called the systolic pressure. This measures the pressure generated when the heart contracts (pumps). It reflects the pressure of the blood against arterial walls.
The bottom, smaller number is called the diastolic pressure. This reflects the pressure in the arteries while the heart is filling and resting between heartbeats.
The American Heart Association has recommended guidelines to define normal and high blood pressure.
Normal blood pressure less than 120/80
Pre-hypertension 120-139/ 80-89
High blood pressure (stage 1) 140-159/90-99
High blood pressure (stage 2) higher than 160/100
As many as 60 million Americans have high blood pressure.
Uncontrolled high blood pressure may be responsible for many cases of death and disability resulting from heart attack, stroke, and kidney failure.
According to research studies, the risk of dying of a heart attack is directly linked to high blood pressure, particularly systolic hypertension. The higher your blood pressure, the higher the risk. Maintaining lifelong control of hypertension decreases the future risk of complications such as heart attack and stroke.
High Blood Pressure Symptoms
High blood pressure usually causes no symptoms and high blood pressure often is labeled "the silent killer." People who have high blood pressure typically don't know it until their blood pressure is measured.
Sometimes people with markedly elevated blood pressure may develop:
headache,
dizziness,
blurred vision,
nausea and vomiting, and
chest pain and shortness of breath.
People often do not seek medical care until they have symptoms arising from the organ damage caused by chronic (ongoing, long-term) high blood pressure. The following types of organ damage are commonly seen in chronic high blood pressure:
Heart attack
Heart failure
Stroke or transient ischemic attack (TIA)
Kidney failure
Eye damage with progressive vision loss
Peripheral arterial disease causing leg pain with walking (claudication)
Outpouchings of the aorta, called aneurysms
About 1% of people with high blood pressure do not seek medical care until the high blood pressure is very severe, a condition known as malignant hypertension.
In malignant hypertension, the diastolic blood pressure (the lower number) often exceeds 140 mm Hg.
Malignant hypertension may be associated with headache, lightheadedness, nausea, vomiting, and stroke like symptoms
Malignant hypertension requires emergency intervention and lowering of blood pressure to prevent brain hemorrhage or stroke.
It is of utmost importance to realize that high blood pressure can be unrecognized for years, causing no symptoms but causing progressive damage to the heart, other organs, and blood vessels.
High Blood Pressure Prevention
High blood pressure may be prevented by living a healthy lifestyle, including some of the following:
- eating a nutritious, low-fat diet;
- exercising regularly;
- decreasing salt (sodium) intake, read food labels so you know the salt content before you buy a product in the grocery store or eating a meal at a fast food restaurant, and avoid adding salt to foods;
- maintain a healthy weight and if you are overweight or obese, try to lose weight;
- drink alcohol in moderation;
- stop smoking;
- get routine health assessments and blood pressure screening;
- taking your blood pressure medications as directed, even if you're feeling fine; and
- reduce stress and practice relaxation techniques, physical activity will help with this.
High Blood Pressure Treatment
Blood pressure control is a lifelong challenge. Hypertension can progress through the years, and treatments that worked earlier in life may need to be adjusted over time. Blood pressure control may involve a stepwise approach beginning with diet, weight loss, and lifestyle changes and eventually adding medications as required. In some situations, medications may be recommended immediately. As with many diseases, the health care practitioner and patient work together as a team to find the treatment plan that will work for that specific individual.
Self-Care at Home
The management and control of high blood pressure involves two major options, lifestyle modification and medication.
Lifestyle Modifications to Manage High Blood Pressure
Weight Control
Aim for a healthy weight range for your height and body type. Your health care practitioner can help you calculate a healthy target weight.
Even a small amount of weight loss can make a major difference in lowering or preventing high blood pressure.
You must burn more calories than you take in to lose weight.
Crash or fad diets are not helpful and may be dangerous.
Some weight loss medications also carry major risks and may even elevate blood pressure, and great caution is advised in using these drugs. Please ask your health care practitioner or pharmacist for help in deciding if a weight loss medication is appropriate for your situation.
Exercise or Increase Physical Activity
Physical activity reduces total cholesterol and bad cholesterol (low density lipoprotein or LDL) and raises the good cholesterol (high density lipoprotein or HDL).
Both the American Heart Association (AHA) and the U.S. Surgeon General recommend 30 minutes of physical activity on most days of the week.
Physical activity includes many daily activities such as cleaning the house, raking the lawn, and walking. Other possible sources of activity can include using the stairs instead of an elevator or escalator, walking for errands instead of driving a car, and participating in a sport or social activity such dancing.
Medical Treatment
In about half of people with high blood pressure, limiting sodium intake by eliminating table salt, cooking salt, and salty and processed foods can reduce blood pressure by 5 mm Hg. Losing weight and participating in regular physical activity can reduce blood pressure further.
If these lifestyle changes and choices don't work, medications should be added. The medications have been proven to reduce the risk of stroke, heart disease, and kidney problems. Do not stop taking your medications without talking to your health care practitioner.
High Blood Pressure Medications
It may take trial and error to find the proper medication or combination of medications that will help control hypertension in each case. It is important to take the medications as prescribed and only discontinue them on the advice of your health care practitioner.
Water Pills (diuretics)
Diuretics are used very widely to control mildly high blood pressure, and are often used in combination with other medications.
They increase sodium excretion and urine output and decrease blood volume. The sensitivity to the effect of other hormones in your body is decreased.
One example of a diuretic is hydrochlorothiazide (HydroDIURIL)
The most commonly used diuretics to treat hypertension include:
hydrochlorothiazide (HydroDIURIL),
the loop diuretics furosemide (Lasix) and torsemide (Demadex),
the combination of triamterene and hydrochlorothiazide (Dyazide), and
metolazone (Zaroxolyn).
Beta-Blockers
Beta-blockers reduce heart rate and decrease the force of heart contraction by blocking the action of adrenaline receptors. Beta blockers are widely prescribed and effective but can cause increased fatigue and decreased exercise tolerance because they prevent an increased heart rate as a normal response to physical activity.
They are also prescribed for people who have associated heart disease,angina, or history of a heart attack.
Examples of beta blockers include, carvedilol (Coreg), metoprolol (Lopressor),atenolol (Tenormin)
Calcium Channel Blockers (CCBs)
Calcium channel blocking agents work by relaxing the muscle in artery walls and by therefore reducing the force of contraction of heart muscle.
Example of calcium channel blockers include, nifedipine (Procardia), diltiazem(Cardizem), verapamil (Isoptin, Calan), nicardipine (Cardene), amlodipine(Norvasc), and felodipine (Plendil)
Angiotensin-Converting Enzyme (ACE) Inhibitors
ACE inhibitors stop the production in the body of a chemical called angiotensin II, which causes blood vessels to contract. Narrower blood vessels are associated with increased blood pressure. Relaxing artery walls leads to lower blood pressure.
Examples of ACE inhibitors include Captopril (Capoten), enalapril (Vasotec),lisinopril (Zestril, Prinivil), quinapril (Accupril), and fosinopril (Monopril)
Angiotensin Receptor Blockers (ARBs)
ARBs work block angiotensin II receptors and prevent vasoconstriction, or narrowing of blood vessels.
Examples of ARBs include losartan (Cozaar), valsartan (Diovan), candesartan(Atacand), and irbesartan (Avapro)
Blockers of Central Sympathetic (autonomic nervous) System
These agents block messages from the brain's autonomic nervous system that contract blood vessels. The autonomic nervous system is the part of the unconscious nervous system of the body that controls heart rate, breathing rate, and other basic functions.
These medications relax blood vessels, thus lowering blood pressure.
An example is clonidine (Catapres)
Direct Vasodilators
Direct vasodilators relax (dilate) the blood vessels to allow blood to flow under lower pressure.
These medications are most often used in times of hypertensive crisis and are injected intravenously to quickly lower blood pressure readings.
Examples include nitroprusside (Nitropress), and diazoxide (Hyperstat)
