Your heart beats about 100,000 times in one day and about 35 million times in a year. During an average lifetime, the human heart will ... are made by the heart valves as they open and close.

Yet one great achievement that frequently goes unrecognized is his studies of human anatomy ... His studies on the heart combined both experimentation and observation. Using an ox's heart to ...

Every year, more than 5 million people in the U.S. are diagnosed with heart valve disease, but this condition has no ...