Mitral valve (3030 bytes)
1: ...icuspid valve]] are known as the atrioventricular valves, because they lie between the atria and the vent...
4: A normally functioning mitral valve allows blood to flow into the left ventricle duri...
7: ... These valve leaflets are prevented from [[mitral valve prolapse|prolapsing]] into the left atrium by the...
9: ...tached to their respective leaflets of the mitral valve by the chordae tendineae.
12: ...een on doppler [[echocardiography]] of the mitral valve as the ''E wave''.

Mitral valve prolapse (9596 bytes)
1: ...ere cases of classic MVP, complications include [[mitral regurgitation]], [[infective endocarditis]], and&...
5: ...lance to a [[bishop]]'s [[miter]], is the [[heart valve]] that prevents the backflow of [[blood]] from th...
7: ..., and ''spongiosa''. Patients with classic mitral valve prolapse have excess [[connective tissue]] that t...
11: For many years, mitral valve prolapse was a poorly understood anomaly associat...
17: ...MVP_subtypes.png|framed|378px|Diagnosis of mitral valve prolapse is based on modern [[echocardiography|ec...

Mitral regurgitation (16050 bytes)
1: ...he abnormal leaking of blood through the [[mitral valve]], from the [[left ventricle]] into the [[left at...
4: ... portions of the mitral valve apparatus can cause mitral regurgitation.
6: ...al valve apparatus itself. The causes of primary mitral regurgitation include:
7: * Myxomatous degeneration of the mitral valve
13: * Balloon valvulotomy of the mitral valve

Mitral stenosis (10771 bytes)
1: ...osis''' is the incomplete opening of the [[mitral valve]] of the [[heart]].
4: ...rcome the increased gradient caused by the mitral valve stenosis.
7: ...f mitral stenosis are calcification of the mitral valve leaflets, and as a form of [[congenital heart dis...
10: ...</sup>. Under normal conditions, a normal mitral valve will not impede the flow of blood from the left a...
13: ...ption>'''Intracardiac pressure tracings in severe mitral stenosis'''</caption>

Valve (2579 bytes)
4: [[fr:Valve]]
14: A '''valve''' is a mechanical device that regulates the flow...
16: ...ere are a number of names for particular types of valve:
18: * [[Ball valve]], which is good for on/off control.
20: * [[Butterfly valve]], particularly in large pipes

Multi-valve (3830 bytes)
1: ...' (or '''multivalve''') when it has more than two valves.
3: ... ''exhaust'' of combustion products. Adding more valves increases the flow of intake and exhaust, potent...
5: ...actuate forked rockers, and [[Cummins]] makes a 4-valve pushrod [[straight-6]] [[Diesel]].
9: ...t the [[SOHC]] 4-valve [[Honda S600]] that a multivalve engine was available to the general public. Howe...
11: ...ph]] also introduced a [[single overhead cam]] 16-valve head on the ''[[Triumph Slant-4 engine|Slant-4]]'...

Valve gear (3857 bytes)
1: ...earts valve gear.jpg|thumb|300px|The [[Walschaert valve gear]] on a [[steam locomotive]] (a [[PRR E6]]s)....
3: ...e mechanism that operates the inlet and exhaust [[valve]]s to admit high-pressure [[steam]] into the [[cy...
5: ...k efficiency is achieved by only having the inlet valve open for a short time and then letting the steam ...
9: ...erive the motion of a [[slide valve]] or [[piston valve]] from the motion of the main crank/[[big end]]. ...
11: ... locomotives overall ever were fitted with poppet valves.

Butterfly valve (623 bytes)
1: ...st and reliable design. However, unlike the ball valve, the plate does not rotate out of the flow of wat...

Reed valve (1765 bytes)
1: ...oss opposite sides of the valve much like [[heart valve]]s do. They are intended to restrict flow to a si...
5: ...nds, it raises the crankcase pressure causing the valve to close to retain the mixture and pressurize it ...
7: ...alone, reed valves are not as precise as [[rotary valve]]s since physical [[inertia]] causes them to open...
9: The repeated flexing of the valve material eventually causes metal versions to fati...
13: ... increasing the internal pressure and closing the valves. The cycle then repeats.

Rotary valve (415 bytes)
3: ...trumpets are almost always equipped with [[piston valve]]s instead.

Spiral valve (314 bytes)
1: ...oblem by having a '''spiral valve''', or a scroll valve, inside the intestine to increase the absorptive ...

Relief valve (284 bytes)
1: ...t it is for liquids only. A [[Safety valve|safety valve]] is for gases only.

Sleeve valve (6028 bytes)
1: ...t fell from use quickly due to advances in poppet-valve technology and their tendency to burn considerabl...
3: ...ring wrapped around the ''valve stem'' closes the valve when the cam stops pushing on it.
5: ...go into the huge camshaft needed to push the huge valves and their equally huge springs.
7: ...the sleeve open and close the ports like a poppet valve would, but do so by being rotated into position. ...
9: ...and the '''rotating head''' version of the sleeve valve system did not see widespread use.

Chemigation valve (724 bytes)
1: ...me governments require the use of two chemigation valves installed in series if hazardous chemicals are t...

Ball valve (1282 bytes)
1: ...ge:ballvalve.jpg|thumb|right|schematic 3 way ball valve]]
2: ...there is a danger of [[water hammer]]. Some ball valves are equipped with an [[actuator]] that may be pn...
4: ...h a T shaped hole through the middle. With such a valve the flow can be directed to either one or the ot...

Blowoff valve (1611 bytes)
1: {{merging|target=Pressure relief valve}}
3: A '''blowoff valve''' is a [[vacuum]] operated [[valve]] that is located after a [[turbocharger]] on an ...
5: ... called a "dump valve", "bypass valve" or "hooter valve".
7: '''Blowoff valves''' are generally not required on [[automatic tra...

Desmodromic valve (1019 bytes)
1: ...ing on the more conventional springs to close the valves.
3: ..."operated". It is usual to say that action on the valve is "positive" in both cases, in other words, both...
10: *[[Poppet valve]]
11: *[[Sleeve valve]]
13: [[Category:Engine valves]]

Aortic valve (3989 bytes)
1: ... '''aortic valve''' is one of the [[heart valve | valves]] of the [[heart]]. It lies between the [[left ...
4: ...he aortic valve has three cusps. When the aortic valve is open, the normal size of the [[orifice]] is 3-...
7: ... aortic valve to close. The closure of the aortic valve contributes the A₂ component of the se...
9: ==Bicuspid aortic valve==
10: ...0 years earlier than in people with normal aortic valves.

Heart valve (5029 bytes)
1: In [[anatomy]], the '''heart valves''' are [[valve]]s in the [[heart]] that prevent blood from flowi...
3: There are four valves of the heart:
4: * Two atrioventricular (AV) valves - ensure blood flows from the atria to the ventr...
5: * Two semilunar valves - these are present in the arteries leaving the ...
7: ... in pressure on each side. The sound of the heart valves shutting causes the [[heart sounds]].

Poppet valve (4329 bytes)
1: [[image:poppetvalve.jpg|right|thumb|poppet valve]]
2: ...cycle]] and [[auto racing]] engines, eliminating 'valve float' at high [[RPM]].
4: ...sk are made of different steel [[alloy]]s, or the valve stems may be hollow and filled with [[sodium]] to...
6: ...RPM]], also the valve lift varies. See [[variable valve timing]].
8: ...alve was in the [[cylinder head]], and later both valves moved to the head.

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