A new program based on a smartphone app is designed to help people lend a hand and save lives.

PulsePoint is being announced this morning, with more than half of the metro area already signed up, including the communities served by the Central Jackson County Fire Protection District – Blue Springs, Grain Valley and Lake Lotawana.

Here’s how it works: People who have CPR certification download the app. When there’s a heart emergency, those within half a mile get an alert and the chance to respond. That can an off-duty emergency responder or anyone else with CPR certification.

An ambulance can take a few minutes to arrive, and proponents point out that CPR -- cardiopulmonary resuscitation -- can be a vital bridge. According to PulsePoint, in cardiac emergencies, the chances of survival drop 10 percent for minute without resuscitation.

Barbara Hensley of the Mid-America Regional Council described the program, which is already up and running, on Tuesday. It was activated during an incident at the Great Wolf Lodge and showed that it works, she said.

“Hopefully we can bring on more cities and counties as we go forward,” she said.