Sudden Cardiac Arrest (SCA) is a condition in which the heart suddenly and unexpectedly stops beating. When this happens, blood stops flowing to the brain & other vital organs.
SCA usually causes death is not treated within minutes. The window of opportunity for using an AED is small defibrillation is more successfull if preformed within 5 minutes of the SCA. The chances of survival decrease 7-10% with every minute that passes after the arrest.