The Saudi Gazette Heart surgery is done to correct problems with the heart. More than half a million heart surgeries are done each year in the United States for many heart problems. Heart surgery is used for both children and adults. This report discusses heart surgery for adults. Traditional heart surgery, often called open-heart surgery, is done by opening the chest wall to operate on the heart. Surgeons cut through the patient's breastbone (or just the upper part of it) to open the chest. Once the heart is exposed, the patient is connected to a heart-lung bypass machine where the machine takes over the heart's pumping action and moves blood away from the heart. This allows surgeons to operate on a heart that isn't beating and that doesn't have blood flowing through it. The definition of open heart surgery has become confusing because new procedures are being done on the heart through smaller cuts. Some new procedures are being done with the heart still beating. Another type of heart surgery is called off-pump, or beating heart, surgery. It's like traditional open-heart surgery, but it doesn't use a heart-lung bypass machine. Off-pump heart surgery is limited to coronary artery bypass grafting, CABG. Many heart surgeries can now be done through small incisions (cuts) between the ribs. This is called minimally invasive heart surgery. This type of heart surgery may or may not use a heart-lung bypass machine. Description u Your heart surgeon will make a 2-inch to 5-inch-long surgical cut in the chest wall. Muscles in the area will be divided so your surgeon can reach the heart. The surgeon can fix or replace a valve or perform bypass surgery. u During endoscopic surgery, your surgeon makes one to four small holes in your chest. Then he uses special instruments and a camera to perform the surgery. u During robot-assisted valve surgery, the surgeon makes two to four tiny cuts (about 1/2 inch to 3/4 inch) in your chest. The surgeon uses a special computer to control robotic arms during the surgery. The surgeon sees a three-dimensional view of the surgery on the computer. This method is very precise. You will not need to be on a heart-lung machine for these types of surgery. However, your heart rate will be slowed with medicine or a mechanical device. If there is a problem with these procedures, the surgeon may have to open the chest to do the surgery. The most common type of heart surgery for adults is coronary artery bypass grafting (CABG). During CABG, surgeons use healthy arteries or veins taken from another part of the body to bypass (that is, go around) blocked heart arteries. CABG relieves chest pain and reduces the risk of heart attack. Heart surgery also is done to: u Repair or replace valves that control the direction of blood flow through the heart u Repair abnormal or damaged structures in the heart u Implant medical devices that help control the heartbeat or support heart function and blood flow u Replace a damaged heart with a healthy heart from a donor These nontraditional methods of heart surgery (off-pump and minimally invasive) may reduce risks and speed up recovery time. Studies are under way to compare these types of heart surgery with traditional open-heart surgery. The results of these studies will help doctors decide the best surgery to use for each patient. Outlook The results of heart surgery in adults often are excellent. Heart surgery can reduce symptoms, improve quality of life, and increase lifespan. To understand heart surgery, it's helpful to know how a normal heart works. Heart in motion Your heart is a muscular organ that pumps blood to your body, it is at the center of the circulatory system. This system consists of a network of blood vessels, such as arteries, veins, and capillaries. These blood vessels carry blood to and from all areas of your body. An electrical system controls your heart and uses electrical signals to contract the heart's walls. When the walls contract, blood is pumped into your circulatory system. Inlet and outlet valves in your heart chambers ensure that blood flows in the right direction.Without the heart's pumping action, blood can't move throughout your body. Your blood carries the oxygen and nutrients that your organs need to work well. Blood also carries carbon dioxide (a waste product) to your lungs so you can breathe it out. A healthy heart supplies the body with the right amount of blood at the rate needed to work well. If disease or injury weakens your heart, your body's organs won't receive enough blood to work normally. Heart Disease Heart disease can disrupt a heart's normal electrical system and pumping functions. Diseases and conditions of the heart's muscle make it hard for your heart to properly pump blood. Damaged or diseased blood vessels make the heart work harder than normal. Problems with the heart's electrical system, called arrhythmias (ah-RITH-me-ahs), can make it hard for the heart to pump blood efficiently. The heart's electrical system is made up of three main parts: u The sinoatrial (SA) node, located in the right atrium of your heart u The atrioventricular (AV) node, located on the interatrial septum close to the tricuspid valve u The His-Purkinje system, located along the walls of your heart's ventricles A heartbeat is a complex series of events. These events take place inside and around your heart. A heartbeat is a single cycle in which your heart's chambers relax and contract to pump blood. This cycle includes the opening and closing of the inlet and outlet valves of the right and left ventricles of your heart. Each heartbeat has two basic parts: diastole and systole. During diastole, the atria and ventricles of your heart relax and begin to fill with blood. At the end of diastole, your heart's atria contract (atrial systole) and pump blood into the ventricles. The atria then begin to relax. Your heart's ventricles then contract (ventricular systole), pumping blood out of your heart. Each beat of your heart is set in motion by an electrical signal from within your heart muscle. In a normal, healthy heart, each beat begins with a signal from the SA node. This is why the SA node sometimes is called your heart's natural pacemaker. Your pulse, or heart rate, is the number of signals the SA node produces per minute. The signal is generated as the vena cavae fill your heart's right atrium with blood from other parts of your body. The signal spreads across the cells of your heart's right and left atria. This signal causes the atria to contract. This action pushes blood through the open valves from the atria into both ventricles. The signal arrives at the AV node near the ventricles. It slows for an instant to allow your heart's right and left ventricles to fill with blood. The signal is released and moves along a pathway called the bundle of His, which is located in the walls of your heart's ventricles. From the bundle of His, the signal fibers divide into left and right bundle branches through the Purkinje fibers. These fibers connect directly to the cells in the walls of your heart's left and right ventricles (see yellow on the picture in the animation). The signal spreads across the cells of your ventricle walls, and both ventricles contract. However, this doesn't happen at exactly the same moment. The left ventricle contracts an instant before the right ventricle. This pushes blood through the pulmonary valve (for the right ventricle) to your lungs, and through the aortic valve (for the left ventricle) to the rest of your body. As the signal passes, the walls of the ventricles relax and await the next signal. This process continues over and over as the atria refill with blood and more electrical signals come from the SA node. __
