No. A heart attack (myocardial infarction) occurs when the heart’s blood supply is reduced or blocked. The heart muscle becomes injured or may start to die. During a heart attack, the victim is conscious. In fact, the victim may complain about symptoms.
An SCA is an electrical problem in the heart which causes the heart to beat in an irregular, inefficient manner. Since the blood can’t circulate to the brain, the victim passes out.
A heart attack victim has a pulse but an SCA victim does not.
You don’t have to remember these distinctions. When the AED instructs you to put the pads on the victim, it will sense the heart rhythm and determine the best steps to take, giving you guidance all along the way.