What is sudden cardiac arrest (SCA)?

Sudden cardiac arrest (SCA) refers to a critical condition where the heart unexpectedly stops beating effectively due to a malfunction of its electrical system. This electrical malfunction disrupts the normal rhythmic contractions of the heart, leading to an immediate cessation of blood flow to the brain and other vital organs.

In SCA, the heart may go into a dangerously fast rhythm (ventricular tachycardia) or potentially stop beating altogether (ventricular fibrillation), both of which seriously impede the heart's ability to pump blood. This is distinct from a heart attack, which occurs when blood flow to a part of the heart muscle is blocked. While a heart attack can lead to sudden cardiac arrest, they are not the same condition; SCA is primarily an electrical issue rather than a problem with blood supply to the heart.

Understanding the differences among these conditions is crucial for effective response and treatment, particularly in emergency situations where rapid defibrillation can be lifesaving. This underscores the importance of recognizing SCA as a critical and immediate medical emergency that requires prompt action.