As posted above, CPR is not for a heart attack. It is for cardiac arrest, or a heart that is no longer generating a pulse, and thus not perfusing vital organs such as the brain, lungs, and kidneys. The cardiac arrest victim can lose their pulse for a number of reasons, including a heart attack, though not every heart attack is fatal. CPR should be initiated on any witnessed cardiac arrest and proper training is key to increasing the odds of a successful resuscitation. The American Heart Association has clear and compelling data to demonstrate that CPR is the single most important factor in survivng a cardiac arrest regardless of the cause. CPR will certainly not revive every pulseless victim but without CPR, survival is improbable. Please take a class and learn this life-saving skill.