Pre-Algebra on Khan Academy: No way, this isn't your run of the mill arithmetic. This is Pre-algebra. You're about to play with the professionals. Think of pre-algebra as a runway.
Coronary artery disease. The most common underlying cause of heart attack is atherosclerosis, a condition in which a fatty substance called plaque builds up on the inside walls of blood vessels. When this occurs in the coronary arteries, it's known as coronary artery disease (CAD).
A SCD attack is not the same as a heart attack. SCD is caused by an abnormal heart rhythm due to abnormal âelectrical circuitryâ of the heart. A heart attack is caused by blockage or occlusion of the arteries supplying blood to the heart, causing a portion of the heart muscle to be damaged.