NEW YORK (CBSNewYork)-- Americans of all ages remember fire drills in school. Most people rarely took them seriously, but kids today face a very different reality. Images from Columbine, Colorado ...

The heart doesn’t always beat at the same rhythm. Our heart responds to nervous signals sent from the brain, or to chemicals that the body produces in response to things it sees, hears or smells.

DENVER — The family of a 4-year-old boy whose heart had stopped beating hours earlier gathered at Children’s Hospital Colorado last month to say their final goodbyes to Cartier McDaniel.

Children’s Healthcare of Atlanta’s heart clinics treat about 200 children a year. This includes Audrey Koch, a Roswell teen with a heart condition called Long QT syndrome.

A pacemaker is keeping a 3-year-old South Florida boy's heart beating after he went into cardiac arrest during a trip to a water park over the July 4 weekend.

A good resting heart rate for an adult is usually between 60 and 90 bpm. Athletes can often have a resting heart rate closer to 40 bpm, and for physically fit adults, this is an exceptionally good ...