Basics

• As the measurement of the force of blood against the arteries, blood pressure reveals how hard the heart must work to circulate blood each time it pumps. Blood pressure measures the force of blood in the vessels as the heart pumps (top number/systolic) and when the heart is at rest, between beats (bottom number/diastolic).
  
  Blood pressure is measured by a sphyganomanometer; the results are reported in millimeters of mercury (mm Hg). High blood pressure is diagnosed when the systolic reading is at or above 140 mm Hg and/or the diastolic reading is at or above 90 mm Hg.
  
  Your health-care provider will not diagnose hypertension on the basis of a single reading, but on several readings. For this purpose, your health-care provider may recommend that you monitor and record your blood pressure readings at home and bring the results to your next scheduled visit.
  
  

Types

• When the health-care provider diagnoses high blood pressure, he will determine if it is primary hypertension or secondary hypertension.
  
  

Primary Hypertension

• Primary hypertension is diagnosed in 85-95 percent of those with high blood pressure. Hypertension is considered to be primary when there is no identifiable cause for the condition. Primary hypertension, formerly called essential hypertension, generally has a slow onset, developing over a number of years. There is no cure for primary hypertension, but it can be controlled through lifestyle changes and/or the use of medication.
  
  

Secondary Hypertension

• Physicians diagnose secondary hypertension when an underlying cause for the high blood pressure is present. Such causes may be kidney abnormalities, adrenal gland disease, thyroid disorder, use of certain medications such as oral contraceptives and other conditions.
  
  Unlike primary hypertension, secondary hypertension's onset is generally abrupt.
  
  If the underlying cause of secondary hypertension is successfully controlled or removed, the blood pressure may return to readings within normal limits.
  
  

Pulmonary Hypertension

• The body has two circulatory systems: systemic and pulmonary. The blood pressure that is most often referred to is systemic blood pressure, meaning the pressure of the blood in the arteries throughout the body.
  
  Pulmonary circulation refers to the blood pumped from the heart to the lungs. In rare instances, people are diagnosed with increased pulmonary blood pressure.