Thursday 21 April 2011

Hypertension and its causes





Hypertension is high blood pressure due to narrowing of arteries that carry blood.It makes the heart work harder to pump the blood to the body.It contributes to the hardening of arteries or atherosclerosis and development of heart failure.

  • Normal blood pressure: 120/80 mm-Hg
  • Pre-hypertension : 120-139/80-89 mm-Hg
  • Stage 1 high blood pressure : 140-159/90-99 mm-Hg
  • Stage 2 high blood pressure : 160 / above 100 mm-Hg


Symptoms :                                                 
Hypertension is associated with                    Who is more likely to develop high B.pressure?  
                                                                     
  1. Headache                                         1.People who have a family history of high B.P.
  2. Drowsiness                                       2.People who smoke.
  3. Confusion                                         3.Americans-Africans.
  4. Vision disorders                                4.Women who are pregnant or take birth control pills.
  5. Nausea                                             5..People eating foods with too many fats or salt. 
  6. Vomiting                                           6.People who are overweight or obese.
  7. Chest pain                                        7.Inactive people.
  8. Breathing problems                           8.People consuming too much Alcohol.
Daily routine causes:

  1. Smoking
  2. Being overweight or obese
  3. lack of physical activity
  4. too much salt in diet
  5. too much alcohol consumption
  6. stress
  7. Old age
  8. Genetics
  9. Family history of high blood pressure
  10. Chronic kidney disease
Pathophysiology of Hypertension:

        The lumen of vessels becomes narrow due to deposition of cholesterol.As a result of which the heart has to pump blood with a greater force due to which blood pressure increases.i.e the force on the walls of vessels.Cardiac output is increased in early
stages with total peripheral resistance normal(TPR) but later cardiac output becomes normal but TPR is increased....


It is due to following reasons:
  • Inability of kidney to excrete sodium resulting in natriuretic factors such as Atrial natriuretic factor being secreted to promotes salt excretion with the side effect of raising TPR.
  • An over reactive Renin angiotension system leads to vasoconstriction and retention of sodium and water.the increase in blood volume plus vasoconstriction leads to hypertension.
  • An over-reactive sympathetic system which leads to increase in the beating and pumping rate of heart.
Complications of Hypertension:


        Hypertension is most important risk factor for death in industrialized countries. It increases hardening of arteries thus predisposes people to Heart diseases, Peripheral disease and Strokes.Types of heart diseases that may occur are : Myocardial infraction, Heart failure, and Left ventricular hypertrophy.
Other complications are:
  • Hypertensive retinopathy(damage to blood vessels in retina due to elevated B.P) 
  • Hypertensive nephropathy( damage to kidney due to elevated B.P)
  • Hypertensive encephalopathy(Cerebral dysfunctions due to sudden and sustained elevated B.P)
  • Silent stroke is a type of stroke that does not have any outward symptoms and the patient is typically unaware that he has suffered a stroke.But it can still damage the brain and places the patient at increased risk for major stroke in future.