A decade after World War II, there was still no such thing as open-heart surgery, and yet half a million Americans were dying from heart disease every year. One in a hundred children would suffer and die from congenital heart disease as well, and doctors did little other than predict their deaths. After the first daring operation in 1954 and through the next three decades, five heroic surgeons braved the scorn of their peers, withstood fierce desperation, and faced possible death in order to devise procedures that would save overwhelming numbers of those doomed children and provide hope for a new life to all manner of heart-failing individuals. Devising and mastering heart transplants and bypass surgery, they invented artificial heart valves, the lifesaving pacemaker, and worked toward the holy grail of an artificial heart as their private and professional lives imploded. The story of the Cardiac Cowboys, their outsized personalities, and often self-destructive behavior is a saga more thrilling and exhilarating than fiction.