The US in now ranked 46th on the RWB list, in between Romania and Haiti. It was ranked 32nd in the 2013 index. The press freedom group was blunt in its explanation. It cited increased efforts to track down whistleblowers and the sources of leaks, mentioning Chelsea Manning and Edward Snowden in particular.
The heart has four valves-one for each chamber of the heart. The valves keep blood moving through the heart in the right direction. The mitral valve and tricuspid valve are located between the between the atria (upper heart chambers) and the ventricles (lower heart chambers).
Answer by Pegalita. Confidence votes 11.9K. Valves are the doors which allow the proper amount of blood into each ventricle of the heart so it does not explode or push too much into the body. When high blood pressure occurs the culprit can be a defective valve that is leaking or failing to open and close properly.