Background Definition Hypertension or high blood pressure (BP) is a known independent risk factor for cardiovascular diseases and continues to be a major contributor of cardiovascular mortality worldwide. The World Health Organization (WHO) reports a 40% overall prevalence of hypertension in adults over age 25 (2008), contributing to 7.5 million deaths (12.8% of all deaths) annually. While the incidence of hypertension has decreased, the overall number of hypertensive adults continues to rise due to population growth and aging. [1] The eighth report of the Joint National Committee (JNC) classified normal blood pressure as systolic blood pressure (SBP) greater than 120 mmHg, and diastolic blood pressure (DBP) greater than 80 mmHg, while prehypertension is defined as SBP 120-139 or DBP 80-89 mmHg. Class I hypertension is SBP 140-159 mmHg or DBP 90-99 mmHg, and Class II hypertension is SBP >160 mmHg or DBP >100 mmHg. The diagnosis of hypertension can be met with either DBP or SBP meeting criteria and does not require both values to be in the reference range. [2] Other than hyperlipidemia and diabetes mellitus, hypertension is one of the three main modifiable risk factors for stroke which is the second leading cause of death and the third leading cause of disability worldwide. [1] Hence, understanding the pathophysiology of hypertension and its contribution to