The risk of both fatal and non-fatal cardiovascular diseases increases with an increase in systolic and diastolic blood pressure. A systolic blood pressure of greater than 210 mm Hg and a diastolic blood pressure of higher than 120 mm Hg causes endothelial injury and endothelial thickness due to increased proliferation of cells in tunica intima of the blood vessels. These changes cause a further rise in blood pressure and promote ischemic tissue damage in vital organs. (RANG, H. P., & DALE, M. M.2012). The two main types of hypertension are secondary hypertension and malignant hypertension. Hypertension in which the direct cause is known is termed as secondary hypertension. While on the other hand, malignant hypertension is described as the condition in which the diastolic pressure has a value of above 130 mm Hg. In secondary hypertension, if the direct reason causing the increase in blood pressure is medically treated then immediately the blood pressure falls to normal. However, in malignant hypertension the case is not so straight forward. In most cases, malignant hypertension is very dangerous and if not treated appropriately, is fatal. Secondary hypertension develops slowly and in most cases is asymptomatic. Therefore, secondary hypertension is termed as a “silent killer”. While on the other hand, malignant hypertension has a rapid developmental phase which is associated with severe symptoms and requires immediate medical attention. (KODA-KIMBLE, M. A.2006).
In certain cases of hypertension, the cause is known and such cases are treatable through surgery such as phaeochromocytoma but in majority of cases the cause of hypertension is not known and these are classified under the category of essential hypertension. Some of the early features helpful in diagnosing hypertension are increased cardiac output and increased peripheral resistance. Blood pressure and kidney function have a strong correlation, the significance of which is exhibited when a hypotensive individual receives a kidney from a normotensive individual. Soon after transplantation, the hypertensive patient shows a speedy recovery and his blood pressure continues to stay within the normal range. Hypertension is a direct consequence of raised peripheral resistance which ultimately leads to hypertrophy of left ventricle. The increase in peripheral vascular resistance induces numerous changes in the vasculature and function of vital organs and thus it needs to be corrected in order to prevent further damage to the cardiovascular system. (RANG, H. P., & DALE, M. M.2012). The sympathetic nervous system, rennin angiotensin aldosterone mechanism and tonically active endothelium derived autocoids, are the main systems which work in coordination to ensure that blood pressure remains within a narrow range in a normal individual. Drastic changes in blood pressure produce life threatening consequences such as hemorrhage and coma. Hypertension if left untreated causes severe damage to the human body such as retinal hemorrhages and arteriolar occlusion. However, if hypertension is treated properly by undergoing anti-hypertensivess therapy along with life style modification, the morbidity and the rate of mortality due to cardiovascular diseases is reduced by several degrees. (GOODMAN et al 1996). The administration of anti-hypertensive drugs is