The heart has four chambers. The upper two are the right and left atria. The lower two are the right and left ventricles. Blood is pumped through the chambers, aided by four heart valves. The valves open and close to let the blood flow in only one direction.

Operations to replace poorly functioning heart valves are common procedures. They're done to improve the health and vigor of people with heart valve diseases. The surgeon who'll perform the operation is the best person to talk to about specific questions or concerns. He or she can best explain the details of the surgical procedure and recovery period. A replacement valve may be taken from another human heart (cadaver valve) or pig (porcine valve) or it can be a mechanical one.

People who have damaged, repaired or replaced heart valves are at increased risk for developing an infection of the valve (endocarditis). Until recently, the American Heart Association recommended giving antibiotics to prevent endocarditis to these patients before they had dental work. However, those guidelines have changed — the American Heart Association no longer recommends antibiotics before dental procedures, except for patients at the highest risk for bad outcomes from endocarditis, including:

• those with prosthetic heart valves
• patients who have had endocarditis in the past
• patients with certain types of congenital heart defects, and
• heart-transplant patients who develop a problem with a heart valve.

For all people with prosthetic heart valves, it’s very important to receive antibiotics before certain types of dental work involving the gum tissues, teeth or other soft tissues inside the mouth. This includes routine professional cleaning.

If a person has had heart valve surgery, but has not had a heart valve replaced, their cardiologist or surgeon will tell them if they need antibiotics. People who have had heart valve surgery will probably be placed on an anticoagulant to prevent blood clots from forming.