Hypertension in Hypoxia - Hypertension in Hypoxia - Open Access Pub

DOI10.14302/issn.2329-9487.jhc-14-edt3 Hypertension is a pathophysiological condition, when arterial blood pressure is elevated. The heart works harder to overcome the increased systemic pressure in order to maintain blood flow to cells and tissues. Over time, the additional strain on the heart and arteries slowly leads to deadly sequelae such as congestive heart failure, myocardial infarction, pulmonary embolism, cerebral aneurysm and kidney failure1. Primary hypertension is the most frequent, accounts about 90-95% incidences. It is associated with many factors such as sedentary lifestyle, stress, tobacco smoking, diabetes, high salt intake, potassium deficiency and sodium sensitivity, obesity, alcohol intake and vitamin D deficiency2, 3. Other hand, secondary hypertension is less frequent, and is linked to mainly dysfunctions and disorders associated with central nervous system, kidneys, lungs, vascular and endocrine system4. This review focuses on altitude-associated hypertension in the tourists, trekkers, and mountaineers who visit high altitude and normally reside near sea level. The acute physiological adjustments and early acclimatization that occur in the cardiovascular and pulmonary systems, ensures the oxygen delivery to the cells and tissues despite a significant reduction in the partial oxygen pressure. The review discusses also the high altitude tolerance and adaptations of the mountain dwellers living for generations. The review describes the pathogenesis of hypertension in general and molecular mechanisms of pulmonary hypertensions associated with high altitude hypoxia and different disease conditions. Hypertension is a common health problem, affecting about 33% populations worldwide associated with significant morbidity and mortality5. Hypertension is a chronic elevation of blood pressure (BP) that, in the long-term, causes organ dysfunction and damage. The absolute risk for hypertension even further increases in disease condition such as cardiovascular disease (CVD) when elevated BP coexists with other CVD risk factors, such as diabetes and dyslipidemia. The pathophysiology of hypertension involves a number of mechanisms that interact in complex fashion to influence BP and their derangement further plays a crucial role in developing a severe form. Many factors contribute to the raised blood pressure in hypertensive patients, including cardiac output and systemic vascular resistance, renin-angiotensin-aldosterone system, sympathetic nervous system, endothelial dysfunctions, and obesity and insulin resistance. Cardiac Output and Vascular