Balloon valvuloplasty, also called percutaneous balloon valvuloplasty, is a surgical procedure used to open a narrowed heart valve. The procedure is sometimes referred to as balloon enlargement of a narrowed heart valve.
Balloon valvuloplasty is performed on children and adults who have a narrowed heart valve, a condition called stenosis. The goal of the procedure is to improve valve function and blood flow by enlarging the valve opening. It is sometimes used to avoid or delay open heart surgery and valve replacement.
There are four valves in the heart—the aortic valve, pulmonary valve, mitral valve, and tricuspid valve—each at the exit of one of the heart's four chambers. These valves open and close to regulate the blood flow from one chamber to the next and are vital to the efficient functioning of the heart and circulatory system. Balloon valvuloplasty is used primarily to treat pulmonary, mitral, and aortic valves when narrowing is present and medical treatment has not corrected or relieved the related problems. With mitral stenosis, for example, medical solutions are typically tried first, such as diuretic therapy (reducing excess fluid), anticoagulant therapy (thinning the blood and preventing blood clots), or blood pressure medications. Valvuloplasty is recommended for those patients whose symptoms continue to progress even after taking such medications for a period of time.
Valvular stenosis can be a congenital defect (develops in the fetus and is present at birth) or can be acquired, that is to stem from other conditions. Mitral valve stenosis in adults, for example, is rarely congenital and is usually acquired, either a result of having rheumatic fever as a child or developing calcium obstruction in the valve later in life. Pulmonary stenosis is almost entirely congenital. Aortic stenosis usually does not produce symptoms until the valve is 75% blocked; this occurs over time and is consequently found in people between the ages of 40 and 70. Tricuspid stenosis is usually the result of rheumatic fever; it occurs less frequently than other valve defects.
Childhood symptoms of valve narrowing may include heart dysfunction, heart failure, blood pressure abnormalities, or a murmur. Adult symptoms will likely mimic heart disease and may include blood pressure abnormalities, shortness of breath, chest pain (angina), irregular heart beat (arrhythmia), or fainting spells (syncope). Electrocardiogram (EKG), x ray, and angiography (a special x-ray examination using dye in the vascular system) may be performed to identify valvular heart problems. Depending on the severity of symptoms, cardiac catheterization may also be performed to examine heart valve function prior to recommending a surgical procedure. Valvular angioplasty is performed in children and adults to relieve stenosis. While it offers relief, it does not always cure the problem, particularly in adults, and often valvotomy (cutting the valve leaflets to correct the opening) or valve replacement is necessary at a later date.
Congenital heart-valve disease occurs in one of every 1,000 newborns and is thought to be caused by inherited factors. In 2–4% of valve problems, health or environmental factors affecting the mother during pregnancy are believed to contribute to the defect. Pulmonary valve stenosis represents about 10% of all congenital heart problems. About 5% of all cardiac defects are stenosis of the aortic valve. Valve abnormalities are diagnosed in children and adults of both sexes; 80% of adult patients with stenosis are male, most adults with mitral stenosis are women who had rheumatic fever as a child. Tricuspid stenosis is rarely found in North America and Europe.
In balloon valvuloplasty, a thin tube (catheter) with a small deflated balloon at its tip (balloon-tipped catheter) is inserted through the skin in the groin area into a blood vessel, and then is threaded up to the opening of the narrowed heart valve. The balloon is inflated to stretch the valve open and relieve the valve obstruction.
The procedure, which takes up to four hours, is performed in a cardiac catheterization laboratory that has a special x-ray machine and an x-ray monitor that looks like a regular TV screen. The patient will be placed on an x-ray table and covered with a sterile sheet. An area on the inside of the upper leg will be washed and treated with an antibacterial solution to prepare for the insertion of a catheter. The patient is given local anesthesia to numb the insertion site and will usually remain awake, able to watch the procedure on the monitor. After the insertion site is prepared and anesthetized, the cardiologist inserts a catheter into the appropriate blood vessel, then passes the smaller balloon-tipped catheter through the first catheter. Guided by the xray monitor that allows visualization of the catheter in the blood vessel, the physician slowly threads the catheter up into the coronary artery to the heart. The deflated balloon is carefully positioned in the opening of the valve that is being treated, and then is inflated repeatedly, which applies pressure to dilate the valve. The inflated balloon widens the valve opening by splitting the valve leaflets apart. Once the valve is widened, the balloon-tipped catheter is removed. The other catheter remains in place for six to 12 hours because, in some cases, the procedure must be repeated. A double-balloon valvuloplasty procedure is often performed on certain high-risk patients because it is considered more effective in restoring blood flow.
For at least six hours before balloon valvuloplasty, the patient will have to avoid eating or drinking anything. An intravenous line is inserted so that medications (anticoagulants to prevent clot formation and radioactive dye for x rays) can be administered. The patient's groin area is shaved and cleaned with an antiseptic. About an hour before the procedure, the patient is given an oral sedative such as diazepam (Valium) to ensure that he or she will relax sufficiently for the procedure.
After balloon valvuloplasty, the patient will spend several hours in the recovery room to be monitored for vital signs (such as heart rate and breathing) and heart sounds. During this time, electrical leads attached to an EKG machine will be placed on the patient's chest and limbs, and a monitor will display the electrical impulses of the heart continuously, alerting nurses quickly if any abnormality occurs. For at least 30 minutes after removal of the catheter, direct pressure is applied to the site of insertion; after this a pressure dressing will be applied. The skin condition is monitored. The insertion site will be observed for bleeding until the catheter is removed. The leg in which the catheter was inserted is temporarily prevented from moving. Intravenous fluids will be given to help eliminate the x-ray dye; intravenous anticoagulants or other medications may be administered to improve blood flow and to keep coronary arteries open. Pain medication is administered as-needed. Some patients will continue to take anticoagulant medications for months or years after the surgery and will have regular blood tests to monitor the effectiveness of the medication.
Following discharge from the hospital , the patient can usually resume normal activities. After balloon valvuloplasty, lifelong follow-up is necessary because valves sometimes degenerate or narrowing recurs, a condition called restenosis, which will likely require repeat valvulplasty, valvotomy, or valve replacement.
Balloon valvuloplasty can have serious complications. For example, the valve can become misshapen so that it does not close completely, which makes the condition worse. Embolism, where either clots or pieces of valve tissue break off and travel to the brain or the lungs causing blockage, is another possible risk. If the procedure causes severe damage to the valve leaflets, immediate valve replacement is required. Less frequent complications are bleeding and hematoma (a local collection of clotted blood) at the puncture site, abnormal heart rhythms, reduced blood flow, heart attack, heart puncture, infection, and circulatory problems. Because restenosis is frequent in adult patients with valvular disease, particularly when underlying heart disease or other conditions are present, the procedure is recommended only as an emergency rescue for high-risk patients who are not candidates for valve replacement.
Balloon valvuloplasty is considered a safe, effective treatment in children with congenital stenosis, improving heart function and blood flow. In adults, balloon valvuloplasty may give temporary relief and improve heart function and blood flow, but underlying coronary artery disease or other disease conditions may encourage restenosis, making valve replacement eventually necessary. The most successful valvuloplasty results are achieved in treating narrowed pulmonary valves, although the treatment of mitral valve stenosis is also generally good. The aortic valve procedure is more difficult to perform and is generally less successful.
Heart Owner's Handbook: Congenital Heart Disease and Diseases of the Heart Valves. Texas Heart Institute, New York: John Wiley & Sons, 1996.
Mayo Clinic Practice of Cardiology: Balloon Valvuloplasty. 3rd ed. Edited by Emilio R. Giuliani, et al. St. Louis: Mosby, 1996.
American Heart Association. 7320 Greenville Ave. Dallas, TX 75231. (214) 373-6300. http://www.americanheart.org .
"Heart Valve Problems." Aetna Intelihealth. [cited April 2003]. http://www.intelihealth.com .
Lori De Milto L. Lee Culvert
Balloon valvuloplasty is performed in a hospital cardiac catheterization laboratory, a special room much like an operating room , by a cardiologist or vascular surgeon.