Your heart pumping blood through your arteries puts pressure (tension) on the artery walls. Hypertension (high blood pressure) occurs when blood pressure stays elevated over time. The increased pressure puts a strain on your circulatory system, which can ultimately lead to serious problems, such as stroke, heart disease, kidney failure, and blindness. The June 25, 2008, issue of JAMA includes an article about controlling hypertension. This Patient Page is based on one published in the February 27, 2002, issue of JAMA.