In a healthy heart, blood flows in only one direction. The four valves of the heart prevent blood from flowing backward. But a leaky heart valve, or heart valve regurgitation, causes a backflow of ...

The heart valves play a vital role in ensuring blood flows correctly through the heart and the rest of the body. If they do not function correctly, a person may require surgery to replace the damaged ...

In hydronic heating, to control where heated water goes to various sections of a building, the system might rely on two or more zone valves. A zone valve opens or closes based on demand from a ...