> ♪ well, you can tell by the way i use my walk... ♪ >> reporter: turns out this disco sound has the perfect beat for pumping the chest during c.p.r. recent studies show that compression-only c.p.r. saves lives and many more people are willing to do it. right now, less than a third of people who witness a cardiac arrest step forward. >> focusing on the compressions gets the blood throwing throughout the body which is critical but it also... it minimize the hesitation. >> reporter: starting c.p.r. a.s.a.p. can keep the patient alive until a defibrillate later arrives. what's key to know. >> we'll start with compressions. unzip the jacket, place the heel Get Live News Updates Every Minute from vimarsana.com Curated from 23000 News Agencies."> > ♪ well, you can tell by the way i use my walk... ♪ >> reporter: turns out this disco sound has the perfect beat for pumping the chest during c.p.r. recent studies show that compression-only c.p.r. saves lives and many more people are willing to do it. right now, less than a third of people who witness a cardiac arrest step forward. >> focusing on the compressions gets the blood throwing throughout the body which is critical but it also... it minimize the hesitation. >> reporter: starting c.p.r. a.s.a.p. can keep the patient alive until a defibrillate later arrives. what's key to know. >> we'll start with compressions. unzip the jacket, place the heel Get Live News Updates Every Minute from vimarsana.com Curated from 23000 News Agencies." property="og:description"> > ♪ well, you can tell by the way i use my walk... ♪ >> reporter: turns out this disco sound has the perfect beat for pumping the chest during c.p.r. recent studies show that compression-only c.p.r. saves lives and many more people are willing to do it. right now, less than a third of people who witness a cardiac arrest step forward. >> focusing on the compressions gets the blood throwing throughout the body which is critical but it also... it minimize the hesitation. >> reporter: starting c.p.r. a.s.a.p. can keep the patient alive until a defibrillate later arrives. what's key to know. >> we'll start with compressions. unzip the jacket, place the heel Get Live News Updates Every Minute from vimarsana.com Curated from 23000 News Agencies.">