Cozaar treats one of the causes of left ventricular hypertrophy (LVH), high blood pressure. In most cases, LVH stems from a problem with hypertension, or high blood pressure. LVH is a condition in which the walls of the left heart chamber swell. When treating this problem, Cozaar acts on certain chemicals causing your blood vessels to constrict and creating high blood pressure. By blocking the chemicals, Cozaar allows your blood vessels to relax and helps restore normal blood pressure in your body. This lessens the chances of a stroke in those who suffer from LVH. However, this drug in these situations does not seem to have the same efficacy when given to African Americans compared to other ethnic groups.