Transcatheter Aortic Valve Replacement
The aortic valve is one of four valves that control blood flow in the heart. The aortic valve specifically controls the blood that runs from the heart through your aorta and to the rest of the body. Over time or because of a congenital heart defect, you can develop aortic stenosis—a type of heart valve disease—which is narrowing of the aortic valve. This narrowing blocks the flow of blood to your body and forces your heart to work harder. You may need TAVR to replace a diseased aortic valve or to repair a replacement aortic valve that no longer works. Your doctor may recommend TAVR if you have a medical condition that makes it too risky to replace the valve during open-heart surgery, which is more invasive.
Cardiologists, or doctors who specialize in the heart, typically perform TAVR in a hospital. Before TAVR, your medical team will measure the valve opening, then give you medicines that relax you or put you to sleep, as well as medicines that prevent abnormal blood clots. During the procedure, your doctor will guide a thin, flexible tube called a catheter to your heart through vessels that can be accessed from the groin or thigh, abdomen, chest, neck, or collar bone. Inside the catheter is a folded replacement valve, which your doctor will implant securely within the old valve. Once your doctor is sure the new valve has been placed correctly, he or she will check for leaks and possible complications, such as a problem in the heart’s electrical signaling.
After a TAVR procedure, your hospital stay may be shorter and you may be able to return to daily activities, such as exercising and driving, sooner than with open-heart surgery. However, TAVR carries some risks, including stroke, damage and bleeding where the catheters were inserted; need for permanent pacemaker due to damage to the heart’s electrical signaling during the procedure; and injury to the kidneys or the heart. Sometimes the new valve leaks because it does not fit well. Your doctor may give you medicine to prevent infection or abnormal blood clots. About a month after the procedure, your doctor will test to check how well the valve is working and how well you are healing. You may need follow-up visits every year to make sure the valve continues working as it should.
How It Works- Transcatheter Aortic Valve Replacement
There are several ways your doctor can perform TAVR, depending on your health and the condition of your blood vessels. Your doctor usually guides a tube with the replacement valve through a blood vessel in your groin or thigh, called the femoral artery.
If your femoral artery is too small or damaged by disease, your doctor may guide the tube through vessels that can be accessed from the chest. This approach is called transapical access. Your doctor may cut into your chest through your breastbone or ribs to access the heart directly through the aorta or through the pointed end of the heart, called the apex.
Less commonly, your doctor may guide the tube through vessels accessed from the abdomen, neck, or collar bone.
- Abdomen. NHLBI researchers developed this approach, called transcaval access, to make TAVR available to high-risk patients whose leg arteries are too small or diseased for the standard approach. The doctor makes holes in both the vena cava, a major vein in your abdomen, and the nearby aorta. The doctor guides the tube with the replacement valve first through the vein and then through the aorta to the heart. You may be able to stay awake when the medical team does this procedure. This type of TAVR approach may benefit women, whose blood vessels are usually smaller than men’s are.
- Collar bone. Accessing the heart from the vessel under the clavicle, or collar bone, may be an option if you have had heart surgery before or if you have another condition that makes it more difficult to access other parts of the chest.
- Neck. With transcarotid access, your doctor will cut into one side of your neck to expose the carotid artery and closely monitor you while opening a hole in the artery for the tube. This type of procedure is rare but may be used when other options will not work.
- Septum. In rare cases, your doctor will reach the faulty valve by guiding the tube through a blood vessel from your thigh to the heart and poking a hole through the septum, the wall of tissue that separates the right and left atria of the heart.
Your doctor may also use additional techniques to help prevent complications. New approaches to doing TAVR are making the procedure available to more patients.
In some patients, a replacement valve can push aside an old valve flap, blocking blood flow to the heart. The result—coronary artery obstruction—is a rare but life-threatening complication of TAVR, and NHLBI researchers have invented a technique to prevent it. Called Bioprosthetic Aortic Scallop Intentional Laceration to prevent Iatrogenic Coronary Artery obstruction (BASILICA), the procedure involves using an electrified wire inside a catheter to cut the existing valve flap before placing the new valve. Without this technique, replacing a faulty valve would be too risky for these patients.