Hypertension
Hypertension or High Blood Pressure, medical condition in which constricted arterial blood vessels increase the resistance to blood flow, causing an increase in blood pressure against vessel walls. The heart must work harder to pump blood through the narrowed arteries. If the condition persists, damage to the heart and blood vessels is likely, increasing the risk for stroke , heart attack, and kidney or heart failure. Often called the “silent killer,” hypertension usually causes no symptoms until it reaches a life-threatening stage. Physicians use two measurements to describe blood pressure. Systolic pressure measures blood pressure as the heart contracts to pump out blood. Diastolic pressure measures blood pressure as the heart relaxes to allow blood to flow into the heart. An instrument called a sphygmomanometer measures systolic and diastolic pressure using units of millimeters of mercury (abbreviated mm Hg). Blood pressure is classified in four categories: normal, prehypertensio