Aortic valvuloplasty, also known as balloon aortic valvuloplasty (BAV), is a procedure used to improve blood flow through the

aortic valve 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. Th ...

in conditions that cause

aortic stenosis Aortic stenosis (AS or AoS) is the narrowing of the exit of the left ventricle of the heart (where the aorta begins), such that problems result. It may occur at the aortic valve as well as above and below this level. It typically gets worse ov ...

, or narrowing of the aortic valve. It can be performed in various patient populations including fetuses, newborns, children, adults, and pregnant women. The procedure involves using a

balloon catheter A balloon catheter is a type of "soft" catheter with an inflatable "balloon" at its tip which is used during a catheterization procedure to enlarge a narrow opening or passage within the body. The deflated balloon catheter is positioned, then in ...

to dilate the narrowed aortic valve by inflating the balloon. Valvuloplasty_Aortic

Medical Uses

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 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: * The valve is leaky (aortic insufficiency, also known as ...

(AVR) or transcatheter aortic valve implantation (TAVI). The most common conditions that deem patients too unstable for AVR or TAVI are

pulmonary edema Pulmonary edema, also known as pulmonary congestion, is excessive liquid accumulation in the tissue and air spaces (usually alveoli) of the lungs. It leads to impaired gas exchange and may cause hypoxemia and respiratory failure. It is due t ...

and cardiogenic shock, which BAV attempts to correct to stabilize the patient before definitive surgery. 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. 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. BAV can also be used as

palliation Palliative care (derived from the Latin root , or 'to cloak') is an interdisciplinary medical caregiving approach aimed at optimizing quality of life and mitigating suffering among people with serious, complex, and often terminal illnesses. Wit ...

therapy to improve symptoms in patients who cannot undergo AVR or TAVI due to contraindications. BAV has been performed on fetuses with

congenital heart defect A congenital heart defect (CHD), also known as a congenital heart anomaly and congenital heart disease, is a defect in the structure of the heart or great vessels that is present at birth. A congenital heart defect is classed as a cardiovascul ...

s 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 Hypoplastic left heart syndrome (HLHS) is a rare congenital heart defect in which the left side of the heart is severely underdeveloped and incapable of supporting the systemic circulation. It is estimated to account for 2-3% of all congenital hea ...

. 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. 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 Pregnancy is the time during which one or more offspring develops ( gestates) inside a woman's uterus (womb). A multiple pregnancy involves more than one offspring, such as with twins. Pregnancy usually occurs by sexual intercourse, but can ...

to avoid harm to the fetal

thyroid The thyroid, or thyroid gland, is an endocrine gland in vertebrates. In humans it is in the neck and consists of two connected lobes. The lower two thirds of the lobes are connected by a thin band of tissue called the thyroid isthmus. The thy ...

from the contrast dye needed during the procedure.

Technique

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. In order to reach the aortic valve, a

blood vessel The blood vessels are the components of the circulatory system that transport blood throughout the human body. These vessels transport blood cells, nutrients, and oxygen to the tissues of the body. They also take waste and carbon dioxide away ...

is punctured to introduce the catheter and advance it into the aortic valve. The most common site of entry is the

femoral artery The femoral artery is a large artery in the thigh and the main arterial supply to the thigh and leg. The femoral artery gives off the deep femoral artery or profunda femoris artery and descends along the anteromedial part of the thigh in the f ...

in the groin, but the carotid artery in the neck can also be used. The

umbilical artery The umbilical artery is a paired artery (with one for each half of the body) that is found in the abdominal and pelvic regions. In the fetus, it extends into the umbilical cord. Structure Development The umbilical arteries supply deoxygenated b ...

is used when the procedure is performed on a fetus. There has also been success using the

radial artery In human anatomy, the radial artery is the main artery of the lateral aspect of the forearm. Structure The radial artery arises from the bifurcation of the brachial artery in the antecubital fossa. It runs distally on the anterior part of th ...

in the wrist to gain access.

Ultrasound Ultrasound is sound waves with frequencies higher than the upper audible limit of human hearing. Ultrasound is not different from "normal" (audible) sound in its physical properties, except that humans cannot hear it. This limit varies ...

is commonly used to visualize the vessel being accessed to avoid potential complications. A

wire Overhead power cabling. The conductor consists of seven strands of steel (centre, high tensile strength), surrounded by four outer layers of aluminium (high conductivity). Sample diameter 40 mm A wire is a flexible strand of metal. Wire is c ...

is typically used to guide the balloon catheter from the access site to the aortic valve. Different size balloons are used depending on the age of the patient. 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 A ventricle is one of two large chambers toward the bottom of the heart that collect and expel blood towards the peripheral beds within the body and lungs. The blood pumped by a ventricle is supplied by an atrium, an adjacent chamber in the uppe ...

. 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.

Outcomes

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. The early benefits of BAV in adults typically do not last. The aortic valve becomes narrow again within months. These patients may progress to more definitive treatment such as AVR or TAVI if they are eligible and clinically stable. 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 Aortic regurgitation (AR), also known as aortic insufficiency (AI), is the leaking of the aortic valve of the heart that causes blood to flow in the reverse direction during ventricular diastole, from the aorta into the left ventricle. As a conseq ...

, and death have been reported. Other complications reported include but are not limited to

infection An infection is the invasion of tissues by pathogens, their multiplication, and the reaction of host tissues to the infectious agent and the toxins they produce. An infectious disease, also known as a transmissible disease or communicable dis ...

, damage to the artery being accessed, heart arrythmias, and decreased

kidney function Assessment of kidney function occurs in different ways, using the presence of symptoms and signs, as well as measurements using urine tests, blood tests, and medical imaging. Functions of a healthy kidney include maintaining a person's fluid ...

. 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. Many do not require surgical aortic valve replacement until later on in life, with many patients reaching adulthood before this occurs. 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. A common complication of BAV in children is

, which decreases in frequency the older the child is when the procedure occurs. Other complications include arrythmias, damage to the artery being accessed, as well as death. 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.

References

{{Cardiac procedures Cardiac surgery