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38-471: Beginning in 1971, it has been used to replace aortic valves and mitral valves . It was the first successful tilting-disc valve. It was manufactured first by Shiley Laboratories, then later by Pfizer after that company purchased Shiley. One model of the Bjork–;Shiley valve became the subject of a famous lawsuit and recall after it was shown to malfunction. The Björk–Shiley valve consists of

76-482: A catheter . The choice between SAVR and TAVR often relies on the open-heart surgical risk and indications for other open heart surgeries (etc., coronary bypass, other valve dysfunction). The Bentall procedure is a type of surgical procedure when the aortic valve, aortic root, and ascending aorta are replaced in a single operation. There are two basic types of artificial heart valve : mechanical and tissue. There are alternatives to animal tissue valves. In some cases,

114-459: A human aortic valve can be implanted. These are called homografts . Homograft valves are donated by patients and recovered after the patient expires. The durability of homograft valves is probably the same as for porcine tissue valves. Another procedure for aortic valve replacement is the Ross procedure (after Donald Ross ) or pulmonary autograft . The Ross procedure involves going to surgery to have

152-404: A left, right and posterior cusp. Anatomists have traditionally named them the left posterior (origin of left coronary), anterior (origin of the right coronary) and right posterior. The three cusps, when the valve is closed, contain a sinus called an aortic sinus or sinus of Valsalva. In two of these cusps, the origin of the coronary arteries are found. The width of the sinuses in cross-section

190-496: A single carbon-coated disc in a metal housing. The disc is held in place by two metal struts, an inflow and an outflow strut. The housing is made from the alloy Haynes 25, which is composed of 51% cobalt , 20% chromium , 15% tungsten , and 10% nickel . The Björk–Shiley valve was considered very durable and was widely used in the 1970s. However, later research indicated it was susceptible to long-term wear problems, and could shed microscopic metal fragments. Attempts to improve

228-476: A tunnel (baffle) between the heart's two upper chambers (atria). After surgery: Lifelong follow-up care with a cardiologist is needed. Most infants who undergo surgery have their symptoms relieved and are able to live a normal life. Potential complications that can occur include coronary artery problems, heart valves problems or irregular heart rhythms (arrhythmias). Transposition of the Great Vessels

266-421: Is possible for it to affect the aortic valve, it is not the most likely spot . Evaluation of the aortic valve can be done with several modalities. Auscultation with a stethoscope is quick and easy. It contributes the A 2 component to the second heart sound and changes with inspiration ("splitting") Transthoracic echocardiography (TTE) is used as the first test because it is non-invasive. Using TTE,

304-479: Is the bicuspid aortic valve (fusion of two cusps together) commonly found in Turner syndrome . Once diagnosed, the two options are to repair or replace the valve. Aortic valve repair or aortic valve reconstruction describes the reconstruction of both form and function of the native and dysfunctioning aortic valve. Most frequently it is applied for the treatment of aortic regurgitation. It can also become necessary for

342-476: Is through dilation of the left ventricle and return to normal filling pressures. Inadequate opening of the aortic valve, often through calcific aortic valve disease , results in higher flow velocities through the valve and larger pressure gradients. Diagnosis of aortic stenosis is contingent upon quantification of this gradient. This condition also results in hypertrophy of the left ventricle. A normally functioning valve permits normal physiology and dysfunction of

380-405: Is wider than the left ventricular outflow tract as well as wider than the ascending aorta. The junction of the sinuses with the aorta is called the sinotubular junction. The aortic valve is located posterior to the pulmonary valve and the commissure where the anterior two cusps join together points toward the pulmonary valve. It is these two sinuses that contain the origin of the coronary arteries. In

418-406: The agreement required Pfizer to provide up to $ 300 million for patient or survivor claims in the event of valve fractures. Not all of these valves have been removed and replaced. The risk of valve fracture has been balanced against the risk of the surgery to replace the valve. Decision tools have been published and are available from a trust set up for this purpose during the litigation surrounding

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456-434: The aorta arises from the right ventricle and the pulmonary artery arises from the left ventricle. This switch causes deoxygenated blood from the right heart to be pumped immediately through the aorta and circulated throughout the body and the heart itself, bypassing the lungs altogether. In this same condition, the left heart continuously pumps oxygenated blood back into the lungs through the pulmonary artery, instead of out into

494-431: The aortic valve contributes the A 2 component of the second heart sound (S 2 ). Closure of the aortic valve permits maintaining high pressures in the systemic circulation while reducing pressure in the left ventricle to permit blood flow from the lungs to fill the left ventricle. Abrupt loss of function of the aortic valve results in acute aortic regurgitation (also known as acute aortic insufficiency) and loss in

532-503: The aortic valve removed and replacing it with the patient's own pulmonary valve. A pulmonary homograft (a pulmonary valve taken from a cadaver) or a valvular prothesis is then used to replace the patient's own pulmonary valve. The first minimally invasive aortic valve surgery took place at the Cleveland Clinic in 1996. Endocarditis is infection of the heart and this often results in vegetations growing on valves. While it

570-434: The baby's body. Surgery: The arterial switch operation is a surgery where the pulmonary artery and the aorta are moved to their normal positions. This is the most common surgery done to correct dextro-TGA, and is considered the definitive treatment. The atrial switch operation is an alternative surgical option when the arterial switch is not feasible due to the particular coronary artery anatomy. This operation creates

608-430: The body's circulation as it normally would. In effect, two separate "parallel" circulatory systems are created. It is called a cyanotic congenital heart defect (CHD) because the newborn infant turns blue (cyanotic) from the lack of oxygen. Levo-Transposition of the great arteries (also known as Levo-TGA, congenitally corrected TGA, double discordance, or ventricular inversion) is a rare, acyanotic heart defect in which

646-440: The congenital disease known as transposition of the great arteries , these two valves are reversed (the anterior valve is the aortic valve) and the origin of the coronaries still follows this "rule" that the origins are in the sinuses facing the pulmonary valve. [REDACTED] The term "semilunar" refers to an approximate half-moon shape of the valve leaflets. When the left ventricle contracts ( systole ), pressure rises in

684-401: The costs of heart surgery to replace the valve. 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 . The aortic valve normally has three cusps or leaflets, although in 1–2% of

722-426: The degree of stenosis and insufficiency can be quantified to grade the valve dysfunction. Transesophageal echocardiography is less often used for aortic stenosis & insufficiency because the angle between the probe and the aortic valve is not optimal (the best window is a transgastric view). MRI and CT can be used to evaluate the valve, but much less commonly than TTE. Quantification of the maximum velocity through

760-405: The design of the valve and speed manufacturing, however, led to a weaker structure, with serious consequences. Beginning in 1979, Björk–Shiley valves with the convexo-concave design had a tendency to develop fractures in the outflow strut which could result in catastrophic valve failure and possibly sudden cardiac death. Later analysis revealed that the strut was fracturing at the place where it

798-420: The fetus having TGV. All infants with TGA will need surgery to correct the defect. Life expectancy is only a few months if corrective surgery is not performed. Before surgery: For newborns with transposition, prostaglandins can be given to keep the ductus arteriosus open which allows for the mixing of the otherwise isolated pulmonary and systemic circuits. Thus, oxygenated blood that recirculates back to

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836-418: The great arteries Transposition of the great vessels ( TGV ) is a group of congenital heart defects involving an abnormal spatial arrangement of any of the great vessels : superior and/or inferior venae cavae , pulmonary artery , pulmonary veins , and aorta . Congenital heart diseases involving only the primary arteries (pulmonary artery and aorta) belong to a sub-group called transposition of

874-682: The great arteries ( TGA ), which is considered the most common congenital heart lesion that presents in neonates. Transposed vessels can present with atriovenous , ventriculoarterial and/or arteriovenous discordance . The effects may range from a slight change in blood pressure to an interruption in circulation depending on the nature and degree of the misplacement, and on which specific vessels are involved. Although "transposed" literally means "swapped", many types of TGV involve vessels that are in abnormal positions, while not actually being swapped with each other. The terms TGV and TGA are most commonly used in reference to dextro-TGA – in which

912-413: The left ventricle. When the pressure in the left ventricle rises above the pressure in the aorta, the aortic valve opens, allowing blood to exit the left ventricle into the aorta. When ventricular systole ends, pressure in the left ventricle rapidly drops. When the pressure in the left ventricle decreases, the momentum of the vortex at the outlet of the valve forces the aortic valve to close. The closure of

950-408: The lungs can mix with blood that circulates throughout the body and can keep the body oxygenated until surgery can be performed. Atrial septostomy can also be performed, usually with a cardiac catheter instead of surgery, to enlarge a natural connection between the heart's upper chambers (atria). This will allow for the oxygen-rich and oxygen-poor blood to mix, resulting in improved oxygen delivery to

988-468: The most common type being intracardiac shunts such as atrial septal defect including patent foramen ovale , ventricular septal defect , and patent ductus arteriosus . Stenosis , or other defects, of valves and/or vessels may also be present. When no other heart defects are present it is called 'simple' TGV; when other defects are present it is called 'complex' TGV. Symptoms may appear at birth or after birth. The severity of symptoms depends on

1026-440: The normal diastolic blood pressure resulting in a wide pulse pressure and bounding pulses. The endocardium perfuses during diastole and so acute aortic regurgitation can reduce perfusion of the heart. Consequently, heart failure and pulmonary edema can develop. Slowly worsening aortic insufficiency results in a chronic aortic regurgitation which permits the heart to compensate (unlike acute aortic regurgitataion). This compensation

1064-419: 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. The aortic valve normally has three cusps however there is some discrepancy in their naming. They may be called the left coronary, right coronary and non-coronary cusp. Some sources also advocate they be named as

1102-404: The pressure change due to the fact that the right ventricle, which is adapted for pumping blood into the low-pressure pulmonary circulation, is being tasked with pumping blood at a much higher pressure against the high resistance of the systemic circulation , since it is now in the position of where the left ventricle is typically located. In many cases, TGV is accompanied by other heart defects,

1140-456: The primary arteries are transposed, with the aorta anterior and to the left of the pulmonary artery, and the morphological left and right ventricles with their corresponding atrioventricular valves are also transposed. In other words, the right ventricle is on the left side of the heart and the left ventricle is on the right side of the heart. The systemic and the pulmonary circulation are connected in this condition. Complications can arise from

1178-424: The treatment of aortic aneurysm, or less frequently for congenital aortic stenosis. Replacement of the aortic valve is done by replacing the native valve with a prosthetic valve. Traditionally, this has been a surgical procedure (surgical AVR or SAVR) but a non-surgical option called transcatheter aortic valve replacement (TAVR) or TAVI transcatheter aortic valve implantation delivers a prosthetic valve through

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1216-422: The two main arteries are in swapped positions; however, both terms are also commonly used, though to a slightly lesser extent, in reference to levo-TGA – in which both the arteries and the ventricles are swapped; while other defects in this category are almost never referred to by either of these terms. Dextro-Transposition of the great arteries (also known as dextro-TGA) is a cyanotic heart defect in which

1254-434: The type of TGV, and the type and size of other heart defects that may be present ( ventricular septal defect , atrial septal defect , or patent ductus arteriosus ). Most babies with TGA have blue skin color (cyanosis) in the first hours or days of their lives, since dextro-TGA is the more common type. Other symptoms include: Preexisting diabetes mellitus of a pregnant mother is a risk factor that has been described for

1292-399: The valve "recall". The tools take into account patient age, the size and location of the valve (aortic or mitral) and other factors to come up with a recommendation as to whether surgery to replace the valve is worthwhile. In some patients the risk of surgery to replace the valve is higher than the risk of the valve fracturing. A fund was also established for patient compensation and to pay for

1330-562: The valve results in left ventricular hypertrophy and heart failure. Dysfunctional aortic valves often present as heart failure by non-specific symptoms such as fatigue, low energy, and shortness of breath with exertion. Common causes of aortic regurgitation include vasodilation of the aorta, previous rheumatic fever , infection such as infective endocarditis , degeneration of the aortic valve, and Marfan's syndrome . Aortic stenosis can also be caused by rheumatic fever and degenerative calcification . The most common congenital heart defect

1368-429: The valve, the area of the opening of the valve, calcification, morphology (tricuspid, bicuspid, unicuspid), and size of the valve (annulus, sinuses, sinotubular junction) are common parameters when evaluating the aortic valve. Invasive measurement of the aortic valve can be done during a cardiac catheterization in which the pressure in the left ventricle and aorta can be measured simultaneously. Transposition of

1406-427: Was welded onto the metal valve ring. One end of the strut would fracture first, followed by the second strut some months later. Eventually, 619 of the 80,000 convexo-concave valves implanted fractured in this way, with the patient dying in two-thirds of those cases. The FDA withdrew approval of the convexo-concave valve in 1986. Valves welded by specific welders were at greater risk of fracture. The convexo-concave valve

1444-426: Was withdrawn from the market and multiple lawsuits were filed. In 1992, Pfizer (Shiley's parent company) and patients with defective valves agreed to a settlement, with Pfizer proposing a fund of $ 80 million to $ 130 million in compensation, and to set aside $ 75 million for research to identify recipients of heart valves with a significant risk of fracture. The eventual settlement totaled $ 215 million. A separate part of

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