Pathophysiology BMS 243 Hypertension Dr. Aya M. Serry 2017

Blood Pressure Blood is carried to all parts of the body in vessels called arteries. Blood pressure is the force of blood pushing against the arteries.

When the heart is at rest, between beats, the blood pressure falls. Each time the heart beats (about 60-70 times a minute at rest), it pumps out blood into the arteries. The blood pressure is at its highest level when the heart beats, pumping the blood. When the heart is at rest, between beats, the blood pressure falls. This is called SYSTOLIC pressure. 120/ Top number 80 This is called DIASTOLIC pressure. Bottom number The blood pressure is always given as these two numbers with one above or before the other.

“Normal” blood pressure is when both numbers are lower than 120/80. Category Systolic (Top Number) Diastolic (Bottom Number) Normal Less than 120 Less than 80 “Normal” blood pressure is when both numbers are lower than 120/80. Doctors classify blood pressures under 140/90 as either "normal," or "prehypertension." "Normal" blood pressures are lower than 120/80.

Unless he takes ACTION to prevent it! “Prehypertension” NEW!!! If the blood pressure is in the prehypertensive range: Prehypertension 120-139 80-89 It means that the patient does not have high blood pressure now, but he is likely to develop it in the future. Unless he takes ACTION to prevent it! WE’LL TALK ABOUT SOME OF THOSE ACTIONS HERE IN A FEW MINUTES.

High Blood Pressure When blood pressure stays elevated over a long period of time it is called high blood pressure or “hypertension”. TENSE, SUDDEN EXERTION – CAN ELEVATE YOUR BP TEMPORARILY, EX: “WHITECOAT HYPERTENSION” HIGH BP IS WHEN IT IS ELEVATED OVER A LONG PERIOD OF TIME CHECK REGULARLY - RECORD WHAT YOUR BP IS. SHOW BP CARDS High blood pressure is dangerous because it makes the heart work too hard and contributes to hardening of the arteries .

High Blood Pressure “Hypertension” A blood pressure of 140/90 is considered high blood pressure. High Blood Pressure Systolic Diastolic Stage 1 140-159 90-99 LIKE MANY DISEASES…THERE ARE STAGES, OR LEVELS. HIGH BP ALSO HAS STAGES. STAGE 1 – NEED TO GET REGULAR MEDICAL CARE FROM DOCTOR STAGE 2 – URGENCY HERE – SHOULD GET IN TO SEE YOUR DOCTOR THIS WEEK. GREATER RISK FOR STROKE, HEART ATTACK HERE. * For adults 18 and older who: Are not on medicine for high blood pressure Are not having a short-term serious illness Do not have other conditions such as diabetes and kidney disease Note: When systolic and diastolic blood pressures fall into different categories, the higher category should be used to classify blood pressure level. For example, 160/80 would be stage 2 high blood pressure. There is an exception to the above definition of high blood pressure. A blood pressure of 130/80 or higher is considered high blood pressure in persons with diabetes and chronic kidney disease. Stage 2 160 or higher 100 or higher

High Blood Pressure Warning Signs: “Silent Killer” 1. 2. 3. 4. If undetected or left untreated it can cause: Heart failure Heart attack Kidney disease Blindness

Hypertension etiology The exact causes of high blood pressure are not known, but several factors and conditions may play a role in its development, including: Smoking Being overweight or obese Lack of physical activity Too much salt in the diet alcohol consumption

Stress Older age Genetics (Family history of high blood pressure) Chronic kidney disease Adrenal and thyroid disorders.

Hypertension Complications Increases your risk for : Heart disease & Stroke If left uncontrolled, hypertension can also cause: Heart failure Heart Attack Kidney disease Blindness

Complications of Hypertension High blood pressure is the most important risk factor for stroke. Very high pressure can cause a break in a weakened blood vessel, which then bleeds in the brain. This can cause a stroke. If a blood clot blocks one of the narrowed arteries, it can also cause a stroke. Stroke Heart Attack High blood pressure is a major risk factor for heart attack. The arteries bring oxygen-carrying blood to the heart muscle. If the heart cannot get enough oxygen, chest pain, can occur. If the flow of blood is blocked, a heart attack results. Blindness High blood pressure can eventually cause blood vessels in the eye to bleed. Vision may become blurred or otherwise impaired and can result in blindness. Heart failure The heart is unable to pump enough blood to supply the body's needs. Heart Attack - High blood pressure is a major risk factor for heart attack. The arteries bring oxygen-carrying blood to the heart muscle. If the heart cannot get enough oxygen, chest pain, can occur. If the flow of blood is blocked, a heart attack results. Heart Failure - As people get older, arteries throughout the body "harden," especially those in the heart, brain, and kidneys. High blood pressure is associated with these "stiffer" arteries. This, in turn, causes the heart to work harder. Arteries Kidney disease Kidneys act as filters to rid the body of waste. High blood pressure can narrow and thicken the blood vessels of the kidneys. The kidneys filter less fluid and waste builds up in the blood. The kidneys may fail altogether.

Pathophysiology of hypertension 1 Renin angiotensin aldosteron System(RAAS) 2 Sympathetic control 3 Endothelial control

Renin-Angiotensin-Aldosterone System Renin is a proteolytic enzyme produced by cells of kidney. It is secreted in response to: Decrease in arterial blood pressure. Decrease Na+ . Increased sympathetic nervous activity. Renin acts on a protein ( Angiotensinogen) and cleaves it to produce Angiotensin-I. Angiotensin-I is rapidly converted to Angiotensin-II by ACE (angiotensin converting enzyme) Angiotensin-II stimulates Aldosterone secretion from Adrenal Cortex which causes sodium and water retention..

Renin-Angiotensin-Aldosterone System From liver Angiotensinogen From kidney Renin Angiotensin I ACE Angiotensin II Vasoconstriction Aldosterone secretion Sodium & fluid retention

Sympathetic control of blood pressure Sympathetic stimulation and catcholamines (Adrenaline and nor adrenaline ) Stimulation of Beta receptors vasodilatation BP Stimulation of Alpha receptors vasoconstriction BP Vasoconstriction activated by  -adrenergic receptors would override vasodilatation by  -adrenergic receptors.

Endothelial control Endothelin BP Thromboxane A2 BP Vasoconstriction Vasodilatation Prostacyclin Histamine BP Bradykinin

Treatment of hypertension

Treatment of hypertension Different categories of antihypertensive drugs are used as: Diuretics: Acts on Kidneys to increase excretion of Na and H2O – decrease in blood volume – decreased BP. Angiotensin-converting Enzyme (ACE) inhibitors: Inhibit synthesis of Angiotensin II –decreased BP. α-adrenergic blockers: Bind to alpha adrenergic receptors and blocks the activity, vasodilatation- decreased BP.

Non pharmacological prevention of Hypertension You can take action to prevent getting high blood pressure or take steps to control it! See your doctor for regular blood pressure check ups Maintaining a healthy weight Choose and prepare foods with less salt x Eat a healthy diet rich in vegetables and fruits, and low fat dairy foods Get physically active If you smoke, think about quitting Drinking too much alcohol can raise blood pressure. It also can harm the liver, brain, and heart. Alcoholic drinks also contain calories, which matter if you are trying to lose weight. If you drink alcoholic beverages, have only a moderate amount — one drink a day for women; two drinks a day for men. What counts as a drink? 12 ounces of beer (regular or light, 150 calories), or 5 ounces of wine (100 calories), or 1 ounces of 80-proof whiskey (100 calories). SALT A key to healthy eating is choosing foods lower in salt and sodium. Most Americans consume more salt than they need. The current recommendation is to consume less than 2.4 grams (2,400 milligrams[mg] ) of sodium a day. That equals 6 grams (about 1 teaspoon) of table salt a day. The 6 grams include ALL salt and sodium consumed, including that used in cooking and at the table. For someone with high blood pressure, the doctor may advise eating less salt and sodium, as recent research has shown that people consuming diets of 1,500 mg of sodium had even better blood pressure lowering benefits. These lower-sodium diets also can keep blood pressure from rising and help blood pressure medicines work better. Losing even 10 pounds can lower blood pressure

Live Healthy Our heart health depends on it! 1. GET YOUR BLOOD PRESSURE CHECKED. 2. EAT HEALTHY FOODS. 3. GET PLENTY OF EXERCISE. MAIN MESSAGE – 1,2,3, PREVENTION, PREVENTION, PREVENTION!! YOU ARE IN CONTROL MOST HEART DISEASE RISK FACTORS NOT IN CONTROL OF: AGE FAMILY HX Our heart health depends on it! Source: Your Guide To Lowering Blood Pressure, www.nhlbi.nih.govc