The human heart, long considered the body's emotional center, is still associated with feelings of love, the soul, and the spirit. The Greek philosopher Aristotle believed it to be the seat of sensation and thought, so important to life itself that it never suffered disease. Hippocrates, known as the father of medicine, believed any wound to the heart was fatal.

Today, it is understood that Aristotle and Hippocrates were wrong. Hearts do suffer disease. In fact, heart disease is the number one killer of Americans-according to the American Heart Association, one in every five deaths in the United States is due to heart disease. That is the bad news. The good news is that the heart is much more resilient than ancient doctors believed. It is not only capable of surviving a wound but of being cut open, repaired, and sewn back up, and...