Cardiac catheterization is often used to locate and map blocked blood vessels. A doctor guides a thin plastic tube (called a catheter) through an artery in the arm or leg and then threads it into the coronary arteries. A liquid dye is injected through the catheter. X-rays record the course of the dye as it flows through the arteries. By mapping the dye's flow, the doctor identifies blocked areas. Once the mapping is done, the doctor can decide the best course of action.

A percutaneous transluminal coronary angioplasty (PTCA) is probably better known as angioplasty or balloon angioplasty. In this procedure, the doctor inserts and guides a catheter (or tube) toward the blocked area of the artery. Then, a second catheter with a small balloon on the tip is passed through the first catheter. Once the balloon tip reaches the blocked area, the balloon is inflated. This compresses the plaque build-up, widening the artery for blood flow. The balloon is deflated and removed at the end of procedure.

Just like a highway bypass allows drivers to drive around a certain area prone to congestion, a heart bypass can allow blood to flow around a blocked artery to reach the heart. During a heart bypass, a surgeon removes a healthy blood vessel from another part of the body (usually the leg or inside the chest wall). He or she then uses it to construct a detour around the blocked coronary artery. One end of the vessel is grafted (or attached) right below the blockage, while the other end is grafted right above the blockage. This allows blood to flow to the heart muscle again. In a double bypass surgery, two grafts are performed. In a triple bypass, three grafts. In a quadruple, four grafts.

The most radical form of open heart surgery is when a transplant of the heart or a part of the heart is needed. But where does a “new” heart come from? When a healthy person dies, the heart may be donated to be used in someone else’s body. The process is just like it sounds: A diseased heart is removed and a healthy donor heart is then attached. However, a transplant operation is extremely complicated. First, the donor and the recipient’s tissue types must be perfectly matched, or the recipient’s body could reject the donor heart. During the surgery, many blood vessels have to be detached and re-attached, so the patient must be connected to a heart-lung machine to keep the blood circulating. After the operation, there is still a risk that the patient's systems may reject the new heart. Because of all of these factors, the number of transplants performed is quite low.

Did you know that scientists have experimented with transplanting an animal heart into a human? In 1984, a twelve-day-old baby girl, known as Baby Fae, received the heart of a seven-month-old baboon. A team of medical scientists from Loma Linda University in California performed the operation. Although Baby Fae died twenty-one days later, the experiment provided valuable research information for the future.