Aortic valve 237414 217499496 2008-06-06T09:02:59Z SmackBot 433328 Date the maintenance tags or general fixes The '''aortic valve''' is one of the [[heart valve|valves]] of the [[heart]]. It lies between the [[left ventricle]] and the [[aorta]]. {{Refimprove|date=June 2008}} {{Heart diagram}} ==Function & Physiology== During ventricular [[systole (medicine)|systole]], [[pressure]] rises in 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 aortic pressure forces the aortic valve to close. The closure of the aortic valve contributes the A<sub>2</sub> component of the second [[heart sound]] (S<sub>2</sub>). ==Disease of the aortic valve== There are two protypical processes that can affect the aortic valve - [[aortic stenosis]] in which the valve fails to open fully, thereby obstructing blood flow out from the heart, and [[aortic insufficiency]], also called [[aortic regurgitation]], in which the aortic valve is incompetent and blood flows passively back to the heart in the wrong direction. These two conditions frequently co-exist. * Common causes of [[aortic stenosis]] include [[rheumatic fever]], [[degenerative calcification]], and congenital diseases such as [[bicuspid aortic valve]]. * Common causes of [[aortic regurgitation]] include [[dilation of the aorta]], previous [[rheumatic fever]], infection, i.e. [[infective endocarditis]], [[myxomatous]] degeneration of the aortic valve, and [[Marfan's syndrome]]. ==Bicuspid aortic valve== The most common [[congenital]] abnormality of the heart is the [[bicuspid aortic valve]]. In this condition, instead of three cusps, the aortic valve has two cusps. This condition is often undiagnosed until later in life when the person develops symptomatic aortic stenosis. Aortic stenosis occurs in this condition usually in patients in their 40s or 50s, an average of 10 years earlier than can occur in people with congenitally normal aortic valves. ==Aortic Valve Replacement== [[Aortic valve replacement]] means that a patient's aortic valve is replaced by a different valve. The aortic valve can be affected by a range of diseases and require aortic valve replacement. The valve can either become leaky ([[Mitral regurgitation|regurgitant]] or insufficient) or stuck partially shut ([[Stenosis|stenotic]]). Aortic valve replacement currently requires open heart surgery. Research is being done now to develop valves that can be implanted using a [[catheter]] without open [[heart surgery]]. There are two basic types of artificial heart valve, mechanical valves and tissue valves. Tissue heart valves are usually made from animal tissues, either animal heart valve tissue or animal pericardial tissue. The tissue is treated to prevent rejection and to prevent calcification. There are alternatives to animal tissue valves. In some cases a human aortic valve can be implanted. These are called [[homograft]]s. Homograft valves are donated by patients and harvested after the patient expires. The durability of homograft valves is probably the same for porcine tissue valves. Another procedure for aortic valve replacement is the [[Ross procedure]] (after [[Donald Ross (surgeon)|Donald Ross]]) or pulmonary [[autograft]]. The Ross procedure involves going to surgery to have 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. <ref>[http://www.universitycircle.org/content/healthcare.asp University Circle Inc<!-- Bot generated title -->]</ref> ==Additional images== <gallery> Image:Gray494.png|Heart seen from above. Image:Heartvalve.jpg|A mechanical artificial heart valve with a pivoting disc. Image:BiologicalValves.JPG|A replaceable model of Cardiac Biological Valve Prosthesis. </gallery> ==See also== *[[aortic stenosis]] *[[aortic insufficiency]] *[[Mechanical heart valves]] ==References== <references/> ==External links== * {{SUNYAnatomyFigs|20|07|02}} {{Heart}} [[Category:Cardiac anatomy]] [[Category:Cardiovascular system]] [[de:Aortenklappe]] [[ja:大動脈弁]] [[no:Aortaklaff]] [[nn:Aortaklaff]] [[pt:Valva aórtica]] [[uk:Аортальний клапан]]