Abstract: Arrangements are provided for assembling multiple substrates for coating within a fluidized bed coater so as to deposit a coating of uniform thickness across the entire exterior surface thereof. One embodiment includes a method for coating orthopedic implants having convex and concave surfaces with pyrocarbon by pyrolytic decomposition of a hydrocarbon.

Abstract: Arrangements are provided for assembling multiple substrates for coating within a fluidized bed coater so as to deposit a coating of uniform thickness across the entire exterior surface thereof. One embodiment includes a method for coating orthopedic implants having convex and concave surfaces with pyrocarbon by pyrolytic decomposition of a hydrocarbon.

Abstract: Arrangements are provided for assembling multiple substrates for coating within a fluidized bed coater so as to deposit a coating of uniform thickness across the entire exterior surface thereof. One embodiment includes a method for coating orthopedic implants having convex and concave surfaces with pyrocarbon by pyrolytic decomposition of a hydrocarbon.

Abstract: Arrangements are provided for assembling multiple substrates for coating within a fluidized bed coater so as to deposit a coating of uniform thickness across the entire exterior surface thereof. One embodiment includes a method for coating orthopedic implants having convex and concave surfaces with pyrocarbon by pyrolytic decomposition of a hydrocarbon.

Abstract: Arrangements are provided for assembling multiple substrates for coating within a fluidized bed coater so as to deposit a coating of uniform thickness across the entire exterior surface thereof. One embodiment includes a method for coating orthopedic implants having convex and concave surfaces with pyrocarbon by pyrolytic decomposition of a hydrocarbon.

Abstract: A novel single occluder mechanical heart valve (1, 45) that exhibits reduced closing cavitation and potential blood-damaging hemolysis by utilizing guiderails (14, 54) to create a continuously shifting pivot axis to control hydraulic forces so as to minimize tangential velocity of the occluder (3, 53) at the instant of final closing. These forces are also used to effect a quick initial closing movement from the full open position. In the same way, other guiderails (12, 16, 52, 56) are employed to provide a quick opening response while guiding the occluder (3, 53) to its full open position where to two fairly equal flow channels are created.

Abstract: A heart valve holder-inserter (21, 121) is designed to facilitate easy implantation of a mechanical heart valve prosthesis (23, 123). This holder-inserter, at its distal end, incorporates a pair of diametrically opposed guide members (47, 49, 81, 147, 149) which extend well beyond the leading edge of the prosthesis and which have exterior surfaces (53, 83, 153) of substantial dimension that are smoothly curved and proportioned so as to slowly spread the tissue annulus in order to facilitate easy entrance thereinto of the leading edge portion of the mechanical valve body.

Abstract: Pyrocarbon components have been found to create richer, clearer sound when employed as bridges (19), saddles (1), nuts (2), frets (3), tuning heads (4), pegs (9) and other components which contact the strings in guitars (6, 16), violins (11) and like stringed musical instruments. Bridges/saddles and nuts of stringed instruments produce a marked difference in the sound when pyrocarbon components are used compared with currently used materials. There is a significant increase in sound volume for a given intensity of string movement, along with richer harmonics and a clearer, less muddy sound. The crystalline structure of pyrolytic carbon minimizes the damping of string vibration as it is transferred to the sound-amplifying portion of acoustic instruments, producing a rich, pleasing and higher volume sound. The useful life of strings is increased in contact with pyrolytic carbon components before they go “dead” or break.

Abstract: Arrangements are provided for assembling multiple substrates for coating within a fluidized bed coater so as to deposit a coating of uniform thickness across the entire exterior surface thereof. One embodiment includes a method for coating orthopedic implants having convex and concave surfaces with pyrocarbon by pyrolytic decomposition of a hydrocarbon.

Abstract: A guitar-family-characteristic-sound selector switch (63) is incorporated into an electric guitar and used in conjunction with the normal guitar pickup selector switch (62) and the volume and tone controls. This guitar-family-characteristic-sound selector switch invokes different pickup (61) combinations and resistance/capacitance/inductance circuitry (68) in order to generate sounds characteristic of at least two other guitars in addition to the normal sound of the host guitar. In one implementation, the family selector switch is a single user controllable switch that makes the system is intuitive in that a single guitar-family-characteristic-sound selector switch is all that needs to be operated to put the guitar in the mode of sounding like one of three or more styles of guitars following such selection; the pickup selector, volume and tone controls are used in the usual manner.

Abstract: Pyrocarbon components have been found to create richer, clearer sound when employed as bridges (19), saddles (1), nuts (2), frets (3), tuning heads (4), pegs (9) and other components which contact the strings in guitars (6, 16), violins (11) and like stringed musical instruments. Bridges/saddles and nuts of stringed instruments produce a marked difference in the sound when pyrocarbon components are used compared with currently used materials. There is a significant increase in sound volume for a given intensity of string movement, along with richer harmonics and a clearer, less muddy sound. The crystalline structure of pyrolytic carbon minimizes the damping of string vibration as it is transferred to the sound-amplifying portion of acoustic instruments, producing a rich, pleasing and higher volume sound. The useful life of strings is increased in contact with pyrolytic carbon components before they go “dead” or break.

Abstract: A prosthetic venous valve having a two-piece housing which includes upstream and downstream sections. The upstream section contains a circular seat against which an occluder comes in sealing contact when the valve is in its closed position. The downstream housing section is shaped so as to prevent escape of the occluder downstream and to halt the reciprocating motion of the occluder in the open position where there is an open pathway past the occluder. A plurality of fins on the interior of the downstream housing section or on the surface of the occluder assure there is a blood flow path downstream past the occluder in the open position. The two-piece construction allows the housing sections to be axially spaced apart so that blood comes in contact with the interior surface of the patient's vein immediately downstream of the upstream section of the housing.

Abstract: A prosthetic heart valve comprising a tubular valve body and a pair of leaflets which pivot, or translate and pivot, between open and closed positions. The valve body is of circular interior cross-section except for a pair of diametrically opposed flat wall sections which contain recesses within which the pivot axes of the leaflets are located. Arcuate edges of the leaflets are irregularly shaped so that a pair of protrusions extend radially outward from an otherwise generally semicircular periphery. The protrusions are strategically located so as to contact the interior surface of the valve body in the closed position at arcuately spaced apart locations which flank the centerline of the leaflet. As a result, contact in the closed position occurs at two spaced apart locations rather than at a single location, and at least a minimum gap is established at the central tip of the leaflet which counteracts potential cavitation, noise and hemolysis.

Abstract: A trileaflet heart valve includes a generally annular valve body having an interior wall of nominally circular cross-section into which three wedge-shaped projections radially extend to provide three pairs of flanking flat surfaces between which three leaflets are pivotally supported. The valve body has an outwardly flaring upstream entrance end that, together with the configuration of the leaflets, assures streamlined flow and low transvalvular pressure drop. Wing sections extend laterally in both directions at angles between about 30.degree. and 50.degree. from flat central sections of the leaflets to create V-shaped cross-section leaflet bodies having short flat edge sections along the lateral edges of both wing sections that create a wide open central flow passageway. The three leaflets assume an orientation parallel or nearly parallel to the central axis in full open position.

Abstract: A prosthetic heart valve is shown which incorporates a valve body design and leaflet pivot arrangements that minimize turbulence and shear stresses having a tendency to generate thrombosis. A valve body having an axially curved entrance that is smoothly joined to a generally cylindrical body of extended axial length provides excellent fluid flow characteristics when combined with leaflets that can assume orientations perfectly aligned with the downstream flow of blood. By constructing such a pyrocarbon valve body which receives a metal ring at an appropriate location, suture rings that permit the tissue annulus to directly contact the exterior surface of the cylindrical valve body are accommodated.

Abstract: A trileaflet heart valve includes a generally annular valve body having an interior wall of nominally circular cross-section into which three wedge-shaped projections radially extend to provide three pairs of flanking flat surfaces between which three leaflets are pivotally supported. The valve body has an outwardly flaring upstream entrance end that, together with the configuration of the leaflets, assures streamlined flow and low transvalvular pressure drop. Wing sections extend laterally in both directions at angles between about 30.degree. and 50.degree. from flat central sections of the leaflets to create V-shaped cross-section leaflet bodies having short flat edge sections along the lateral edges of both wing sections that create a wide open central flow passageway. The three leaflets assume an orientation parallel or nearly parallel to the central axis in full open position.

Abstract: A prosthetic heart valve is shown which incorporates a valve body design and leaflet pivot arrangements that minimize turbulence and shear stresses having a tendency to generate thrombosis. A valve body having an axially curved entrance that is smoothly joined to a generally cylindrical body of extended axial length provides excellent fluid flow characteristics when combined with leaflets that can assume orientations perfectly aligned with the downstream flow of blood. By constructing such a pyrocarbon valve body which receives a metal ring at an appropriate location, suture rings that permit the tissue annulus to directly contact the exterior surface of the cylindrical valve body are accommodated.

Abstract: A bileaflet heart valve incorporates a pivot arrangement that minimizes resistance to downstream blood flow in the open position yet has prompt response and therefore minimal regurgitation upon flow reversal. A valve body having an axially curved entrance that smoothly joins a generally cylindrical body of extended axial length provides excellent fluid flow characteristics when combined with leaflets that can assume orientations perfectly aligned with the downstream flow of blood. Identical flat leaflets can assume a parallel orientation in the fully open position during downstream blood flow or can assume other low energy positions. Flat ears, which extend laterally from opposite surfaces of the leaflets, interengage with cavities of unique design having upstream and downstream lobes separated by an intermediate throat portion defined by inward and outward fulcrums.

Abstract: A trileaflet heart valve includes a generally annular valve body having an interior wall of nominally circular cross-section into which 3 wedge-shaped projections radially extend to provide 3 pairs of flanking flat surfaces between which leaflets are pivotally supported and which includes an outwardly flaring upstream entrance end that, together with an elongated axial length, assures streamlined flow and a low transvalvular pressure drop. The leaflets assume an orientation substantially parallel to the central axis in the open position with their swinging movement in the direction of closing being guided by pairs of arcuate ridges and posts which protrude from the flanking flat walls of the projections and which guide the leaflets in a pivoting and translating swinging movement. The downstream ends of the curved ridges are enlarged in cross-section, compared to the upstream ends, and in combination with the posts create stops which determine the desired open position orientation of the three leaflets.

Abstract: A bileaflet heart valve is shown which incorporates a pivot arrangement that minimizes resistance to downstream blood flow in the open position yet has prompt response and therefore minimal regurgitation upon flow reversal. The valve employs a pair of identical flat leaflets that can assume a precisely parallel orientation in the fully open position at or near peak downstream blood flow or can alternatively assume other low energy positions. As the downstream flow of blood slows near the end of a pumping stroke, downstream displacement of the leaflets results in their prerotation toward the closed position orientation, all being controlled by the interengagement of flat ears, which extend laterally from opposite surfaces of the leaflets, and receiving cavities of unique design. The cavities include upstream and downstream lobes separated by an intermediate throat portion defined by inward and outward fulcrums.