Aortic valvuloplasty, also known as balloon aortic valvuloplasty (BAV), is a procedure used to improve blood flow through the aortic valve in conditions that cause aortic stenosis, or narrowing of the aortic valve. It can be performed in various patient populations including fetuses, newborns, children, adults, and pregnant women. [1] [2] The procedure involves using a balloon catheter to dilate the narrowed aortic valve by inflating the balloon. [1]
Guidelines and indications are specific to different patient populations. For adults with aortic stenosis, guidelines suggest that balloon aortic valvuloplasty (BAV) is to be used as a temporary procedure to improve blood flow through the aortic valve to alleviate symptoms and stabilize clinically before having more invasive procedures done, including aortic valve replacement (AVR) or transcatheter aortic valve implantation (TAVI). The most common conditions that deem patients too unstable for AVR or TAVI are pulmonary edema and cardiogenic shock, which BAV attempts to correct to stabilize the patient before definitive surgery. [1] [3] [4] [5] For adult patients with aortic stenosis who need noncardiac related surgeries, BAV can be indicated to decrease the risk of the operation in certain high-risk patients. [1] [3] BAV has been used in adult patients who have shortness of breath and the cause is unclear between aortic stenosis or from a primary lung problem. These patients undergo BAV and if their shortness of breath improves, the cause is deemed to be likely from aortic stenosis and they can undergo AVR or TAVI to correct the aortic stenosis definitively. [3] [4] BAV can also be used as palliation therapy to improve symptoms in patients who cannot undergo AVR or TAVI due to contraindications. [3] [1] [5]
BAV has been performed on fetuses with congenital heart defects involving the aortic valve to improve blood flow within the heart. It is not definitive treatment, but is performed in an attempt to prevent a condition called hypoplastic left heart syndrome. [1] For neonates and children with congenital aortic valve stenosis, BAV is commonly the first type of procedure performed to relieve the stenosis, but is not always a definitive treatment option. [6] [1] [5]
Guidelines suggest performing BAV in pregnant patients with severe aortic stenosis evident by severe symptoms. Changes in blood flow and circulation during pregnancy make it more likely for complications and symptoms to arise in patients with aortic stenosis. When BAV is indicated, it is suggested to attempt to wait until the third trimester to avoid harm to the fetal thyroid from the contrast dye needed during the procedure. [1] [2]
Aortic valvuloplasty relies on placing a catheter with a balloon at the tip in the aortic valve, which is then inflated to widen the narrowed valve. [1] In order to reach the aortic valve, a blood vessel is punctured to introduce the catheter and advance it into the aortic valve. The most common site of entry is the femoral artery in the groin, but the carotid artery in the neck can also be used. The umbilical artery is used when the procedure is performed on a fetus. [1] [7] There has also been success using the radial artery in the wrist to gain access. [7] Ultrasound is commonly used to visualize the vessel being accessed to avoid potential complications. [3] A wire is typically used to guide the balloon catheter from the access site to the aortic valve. [1] Different size balloons are used depending on the age of the patient. [1] In order for the balloon to remain in the proper position while it is being inflated in the aortic valve, blood flow through the valve needs to be temporarily reduced. This is typically achieved by increasing the heart rate through electrical stimulation of the heart muscle or through medications that decrease blood pumping from the left ventricle. [1] The blood pressure and flow across the aortic valve is monitored and repeated inflation of the balloon is sometimes needed to successfully dilate the aortic valve. [1]
After BAV in adults, it is common to have both clinical and symptomatic improvement early on. Clinically, the pressure across the aortic valve is reduced, there is increased blood flow, and the area of the aortic valve is increased due to mechanical dilation of the balloon. Many patients have a reduction of the symptoms associated with severe aortic stenosis, commonly reported as an improvement of their NYHA functional class, which is a way to categorize the severity of heart failure based on reported symptoms. [8] The early benefits of BAV in adults typically do not last. The aortic valve becomes narrow again within months. [8] [1] These patients may progress to more definitive treatment such as AVR or TAVI if they are eligible and clinically stable. [4] [1] BAV in adults has risks and complications associated with it due to the risk of the procedure itself as well as the commonly high-risk patient population that undergoes BAV. Major bleeding, stroke, aortic regurgitation, and death have been reported. [8] Other complications reported include but are not limited to infection, damage to the artery being accessed, heart arrythmias, and decreased kidney function. [3] [1] [8]
It is typical for children to require reintervention after having BAV, whether it be a repeat BAV or more definitive treatment with surgical aortic valve replacement. [6] Many do not require surgical aortic valve replacement until later on in life, with many patients reaching adulthood before this occurs. [9] [1] The outcomes are worse for neonates and infants. This is largely because earlier intervention is required in these patients due to being less clinically stable. [1] A common complication of BAV in children is aortic regurgitation, which decreases in frequency the older the child is when the procedure occurs. [1] Other complications include arrythmias, damage to the artery being accessed, as well as death. [1] [9]
For pregnant patients, data is lacking regarding outcomes of BAV. It is recommended that these patients requiring BAV progress to aortic valve replacement when suitable. Specific risks of performing BAV in pregnant patients include potential harm to the fetus from radiation exposure. [2]
Aortic stenosis is the narrowing of the exit of the left ventricle of the heart, such that problems result. It may occur at the aortic valve as well as above and below this level. It typically gets worse over time. Symptoms often come on gradually with a decreased ability to exercise often occurring first. If heart failure, loss of consciousness, or heart related chest pain occur due to AS the outcomes are worse. Loss of consciousness typically occurs with standing or exercising. Signs of heart failure include shortness of breath especially when lying down, at night, or with exercise, and swelling of the legs. Thickening of the valve without narrowing is known as aortic sclerosis.
The aortic valve is a valve in the heart of humans and most other animals, located between the left ventricle and the aorta. It is one of the four valves of the heart and one of the two semilunar valves, the other being the pulmonary valve. The aortic valve normally has three cusps or leaflets, although in 1–2% of the population it is found to congenitally have two leaflets. The aortic valve is the last structure in the heart the blood travels through before stopping the flow through the systemic circulation.
Tetralogy of Fallot (TOF), formerly known as Steno-Fallot tetralogy, is a congenital heart defect characterized by four specific cardiac defects. Classically, the four defects are:
dextro-Transposition of the great arteries is a potentially life-threatening birth defect in the large arteries of the heart. The primary arteries are transposed.
Mitral stenosis is a valvular heart disease characterized by the narrowing of the opening of the mitral valve of the heart. It is almost always caused by rheumatic valvular heart disease. Normally, the mitral valve is about 5 cm2 during diastole. Any decrease in area below 2 cm2 causes mitral stenosis. Early diagnosis of mitral stenosis in pregnancy is very important as the heart cannot tolerate increased cardiac output demand as in the case of exercise and pregnancy. Atrial fibrillation is a common complication of resulting left atrial enlargement, which can lead to systemic thromboembolic complications like stroke.
Interventional cardiology is a branch of cardiology that deals specifically with the catheter based treatment of structural heart diseases. Andreas Gruentzig is considered the father of interventional cardiology after the development of angioplasty by interventional radiologist Charles Dotter.
Bicuspid aortic valve is a form of heart disease in which two of the leaflets of the aortic valve fuse during development in the womb resulting in a two-leaflet (bicuspid) valve instead of the normal three-leaflet (tricuspid) valve. BAV is the most common cause of heart disease present at birth and affects approximately 1.3% of adults. Normally, the mitral valve is the only bicuspid valve and this is situated between the heart's left atrium and left ventricle. Heart valves play a crucial role in ensuring the unidirectional flow of blood from the atrium to the ventricles, or from the ventricle to the aorta or pulmonary trunk. BAV is normally inherited.
Coarctation of the aorta, also called aortic narrowing, is a congenital condition whereby the aorta is narrow, usually in the area where the ductus arteriosus inserts. The word coarctation means "pressing or drawing together; narrowing". Coarctations are most common in the aortic arch. The arch may be small in babies with coarctations. Other heart defects may also occur when coarctation is present, typically occurring on the left side of the heart. When a patient has a coarctation, the left ventricle has to work harder. Since the aorta is narrowed, the left ventricle must generate a much higher pressure than normal in order to force enough blood through the aorta to deliver blood to the lower part of the body. If the narrowing is severe enough, the left ventricle may not be strong enough to push blood through the coarctation, thus resulting in a lack of blood to the lower half of the body. Physiologically its complete form is manifested as interrupted aortic arch.
Aortic valve replacement is a procedure whereby the failing aortic valve of a patient's heart is replaced with an artificial heart valve. The aortic valve may need to be replaced because:
Cardiac catheterization is the insertion of a catheter into a chamber or vessel of the heart. This is done both for diagnostic and interventional purposes.
A pulmonary artery catheter (PAC), also known as a Swan-Ganz catheter or right heart catheter, is a balloon-tipped catheter that is inserted into a pulmonary artery in a procedure known as pulmonary artery catheterization or right heart catheterization. Pulmonary artery catheterization is a useful measure of the overall function of the heart particularly in those with complications from heart failure, heart attack, arrythmias or pulmonary embolism. It is also a good measure for those needing intravenous fluid therapy, for instance post heart surgery, shock, and severe burns. The procedure can also be used to measure pressures in the heart chambers.
Valvular heart disease is any cardiovascular disease process involving one or more of the four valves of the heart. These conditions occur largely as a consequence of aging, but may also be the result of congenital (inborn) abnormalities or specific disease or physiologic processes including rheumatic heart disease and pregnancy.
Percutaneous aortic valve replacement (PAVR), also known as percutaneous aortic valve implantation (PAVI), transcatheter aortic valve implantation (TAVI) or transcatheter aortic valve replacement (TAVR), is the replacement of the aortic valve of the heart through the blood vessels. The replacement valve is delivered via one of several access methods: transfemoral, transapical, subclavian, direct aortic, and transcaval, among others.
Lutembacher's syndrome is a very rare form of congenital heart disease that affects one of the chambers of the heart as well as a valve. It is commonly known as both congenital atrial septal defect (ASD) and acquired mitral stenosis (MS). Congenital atrial septal defect refers to a hole being in the septum or wall that separates the two atria; this condition is usually seen in fetuses and infants. Mitral stenosis refers to mitral valve leaflets sticking to each other making the opening for blood to pass from the atrium to the ventricles very small. With the valve being so small, blood has difficulty passing from the left atrium into the left ventricle. Septal defects that may occur with Lutembacher's syndrome include: Ostium primum atrial septal defect or ostium secundum which is more prevalent.
The following outline is provided as an overview of and topical guide to cardiology, the branch of medicine dealing with disorders of the human heart. The field includes medical diagnosis and treatment of congenital heart defects, coronary artery disease, heart failure, valvular heart disease and electrophysiology. Physicians who specialize in cardiology are called cardiologists.
A hybrid cardiac surgical procedure in a narrow sense is defined as a procedure that combines a conventional, more invasive surgical part with an interventional part, using some sort of catheter-based procedure guided by fluoroscopy imaging in a hybrid operating room (OR) without interruption. The hybrid technique has a reduced risk of surgical complications and has shown decreased recovery time. It can be used to treat numerous heart diseases and conditions and with the increasing complexity of each case, the hybrid surgical technique is becoming more common.
Apicoaortic Conduit (AAC), also known as Aortic Valve Bypass (AVB), is a cardiothoracic surgical procedure that alleviates symptoms caused by blood flow obstruction from the left ventricle of the heart. Left ventricular outflow tract obstruction (LVOTO) is caused by narrowing of the aortic valve and other valve disorders. AAC, or AVB, relieves the obstruction to blood flow by adding a bioprosthetic valve to the circulatory system to decrease the load on the aortic valve. When an apicoaortic conduit is implanted, blood continues to flow from the heart through the aortic valve. In addition, blood flow bypasses the native valve and exits the heart through the implanted valved conduit. The procedure is effective at relieving excessive pressure gradient across the natural valve. High pressure gradient across the aortic valve can be congenital or acquired. A reduction in pressure gradient results in relief of symptoms.
Fetal aortic stenosis is a disorder that occurs when the fetus’ aortic valve does not fully open during development. The aortic valve is a one way valve that is located between the left ventricle and the aorta, keeping blood from leaking back into the ventricle. It has three leaflets that separate when the ventricle contracts to allow blood to move from the ventricle to the aorta. These leaflets come together when the ventricle relaxes.
Alain Cribier, FACC, FESC is a French interventional cardiologist, who is a Professor of Medicine and Director of Cardiology at the University of Rouen's Charles Nicolle Hospital. Alain Cribier is best known for performing the world's first transcatheter aortic valve implantation in 2002, the first mitral commissurotomy in 1995 and the first balloon aortic valvuloplasty in 1986.
Percutaneous pulmonary valve implantation (PPVI), also known as transcatheter pulmonary valve replacement (TPVR), is the replacement of the pulmonary valve via catheterization through a vein. It is a significantly less invasive procedure in comparison to open heart surgery and is commonly used to treat conditions such as pulmonary atresia.