Direct suture orifice for mechanical heart valve

A mechanical heart valve for implantation in a heart of a patient includes an orifice body having an outer circumference and defining a lumen for blood flow therethrough. At least one leaflet carried in the lumen of the orifice body is movable between an open position, allowing flow through the lumen, and a closed position blocking flow through the lumen. A flange ring around the outer circumference of the orifice body includes a plurality of suture holes defined therein. The suture holes are adapted for receiving a suture and thereby attaching the heart valve to tissue of the heart.

FIELD OF THE INVENTION 
The present invention relates to mechanical heart valve prostheses. More 
specifically, the invention relates to a heart valve orifice which is 
directly sutured to the heart tissue. 
BACKGROUND OF THE INVENTION 
Implantable mechanical heart valves are used for replacement of defective 
valves in hearts of patients. The valves are typically sutured to a tissue 
annulus that is left when the surgeon removes the existing valve from the 
patient's heart. One common technique employs a sewing ring or suture cuff 
which is attached to and extends around the outer circumference of the 
mechanical valve orifice. The sewing cuff is made of a biocompatible 
fabric suitable for allowing a needle and suture to pass therethrough. The 
sewing cuff is securely attached to the circumference of the mechanical 
valve orifice using sutures which are passed through the tissue annulus 
and the sewing cuff. The sutures are tied snugly, thereby securing the 
valve to the heart. 
Sewing cuffs are expensive to manufacture and are difficult to secure to 
the valve orifice. It is also desirable to provide a large lumen through 
the valve orifice relative to the overall valve diameter. However, 
techniques for attaching the sewing cuff to the valve orifice typically 
require the area of the valve lumen be reduced to accommodate an 
attachment mechanism. For example, the sewing cuff is typically retained 
between two rims of the valve orifice. The lower rim normally defines the 
outside diameter of the valve orifice and thus limits the size of the 
valve lumen. 
Another technique for attaching heart valves uses a series of pins which 
pierce the tissue annulus of the heart. The pins are crimped or bent, 
thereby locking the valve to the heart tissue and preventing the valve 
from separating from the heart. This technique is described in U.S. Pat. 
Nos. 3,574,865 and 3,546,710. 
SUMMARY OF THE INVENTION 
The present invention is a prosthetic heart valve for implantation in a 
heart. The heart valve includes an orifice body having an outer 
circumference and defining a lumen for blood flow therethrough. At least 
one leaflet occluder carried in the lumen of the orifice body is movable 
between an open position, which allows blood flow through the lumen, and a 
closed position which blocks blood flow through the lumen. A flange ring 
around the outer circumference of the orifice body includes a plurality of 
suture holes. The suture holes are adapted for receiving a suture and 
thereby attaching the heart valve to tissue of the heart. 
In one embodiment, a suture receiving element around the outer 
circumference of the orifice body is axially spaced apart from the flange 
ring. The suture receiving element is adapted for receiving a suture 
passed through a suture hole in the flange ring and securing heart tissue 
between the flange ring and the suture receiving element.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
Figures 1A, 1B, 1C and 1D show exploded top perspective, top perspective, 
top plan and side plan views, respectively, of a mechanical heart valve in 
accordance with one embodiment of the present invention. The present 
invention provides a heart valve 10 having a suture flange for directly 
attaching to the tissue annulus of a heart. This provides a quick, 
convenient and easy method for attaching a prosthetic heart valve to the 
heart tissue annulus that remains after the native heart valve is removed 
by a surgeon. The technique also eliminates the need for a sculpted sewing 
ring or suture cuff used as a method of attaching the valve to the tissue 
annulus, thereby reducing the manufacturing costs of the valve. 
Valve 10 includes orifice body 12, orifice flange (or flange ring) 14, 
flange ring 16 and leaflets 18 (shown in FIG. 1C). Orifice flange 14 is 
formed integral with orifice 12. Orifice flange 14 has a plurality of 
suture holes 20 formed therein. A cuff gasket 38 is positioned proximate 
orifice flange 14. Similarly, flange ring 16 includes suture holes 22. 
Orifice body 12 includes pivot guards 24 and central annulus 26 in which 
leaflets 18 and mated spherical pivots 28 are engaged. Leaflets 18 are 
movable about mated spherical pivots 28 between an open position which 
permits blood flow through lumen area 30, as in FIG. 1C, and a closed 
position which blocks blood flow through lumen area 30 defined in orifice 
body 12. Orifice flange ring 16 is separate from valve 10 and can be 
formed of a biocompatible metallic, polymeric or fabric material such as 
MP35N, Acctal or polyester, depending on the surgeon's needs and 
preferences. 
As shown in FIG. 1D, flange ring 16 is axially spaced apart from orifice 
flange 14 by tissue annulus 36 and cuff gasket 38. Also shown in FIG. 1D, 
an outer annulus region 40 is formed between flange ring 16 and the end of 
orifice 12 which allows for thickness variations in tissue annulus 36. 
Valve 10 is attached to tissue annulus 36 by passing a plurality of 
sutures 42 through suture holes 22 in flange ring 16, through tissue 
annulus 36, through cuff gasket 38, through holes 20 in orifice flange 14 
of valve 10 and knotting sutures 42 securely with knots 44. Sutures 42 
also secure flange ring 16 in position as shown in FIG. 1D, thereby 
clamping tissue annulus 36. Suture holes 20 and 22 are generally aligned 
to facilitate the passing of sutures 42. The total number of sutures 42 is 
determined by the surgeon. All holes 20,22 need not be used. The inner 
diameter of tissue annulus 36 fits snugly around the valve outer diameter 
39 when valve 10 is inserted. 
FIGS. 2A, 2B, 2C and 2D show exploded top perspective, top perspective, top 
plan and side plan views, respectively, of mechanical heart valve 50 in 
accordance with another embodiment. Heart valve 50 includes orifice body 
52 having integral orifice flange or flange ring 54 and flange ring 56. 
Orifice body 52 includes pivot guards 58 and mated spherical pivots 60, 
adapted for carrying leaflets 61 in lumen area 62. Orifice ring 54 is 
formed of a plurality of radial extensions 64 having suture retention lips 
66. A cuff gasket 68 is positioned proximate orifice ring 54. Suture 
receiving notches 70 are formed between radial extensions 64. Flange ring 
56 includes a plurality of suture holes 72 which are generally aligned 
with notches 70 as shown in FIG. 2C. 
Valve 50 is attached to a heart tissue annulus 74 using sutures 76, as 
shown in FIGS. 2B and 2D. Sutures 76 extend through suture holes 72, 
through tissue annulus 74, through cuff gasket 68, over a radial extension 
64, through suture notches 70 and are knotted securely. Suture retention 
lips 66 prevent sutures 76 from sliding off extension 64. The inner 
diameter of tissue annulus 74 fits snugly around the valve outer diameter 
78 when valve 50 is inserted. The position of flange ring 56 also forms an 
annulus extension 80 of orifice 52 which allows for variations in the 
tissue annulus thickness. 
FIGS. 3A, 3B, 3C and 3D show exploded top perspective, top perspective, top 
plan and side plan views, respectively, of mechanical heart valve 100 in 
accordance with another embodiment. As shown in FIG. 3A, valve 100 
includes orifice body or housing 102 and flange rings (orifice flanges) 
104 and 106. Orifice body 102 includes pivot guards 108 and rim 110 which 
is formed integral with orifice body 102 and extends around the outer 
circumference of orifice body 102. Upper orifice outer diameter 114 and 
lower orifice outer diameter 116 are sized to match the inner diameter of 
their respective flange rings 104 and 106. Flange ring 104 includes a 
plurality of suture holes or openings 118, and flange ring 106 includes a 
plurality of suture holes or openings 120. FIGS. 3B and 3D show valve 100 
with flange rings 104 and 106 abutted against rim 110. Suture holes 118 
are substantially aligned with suture holes 120 as shown in FIG. 3D. 
Attachment to heart tissue annulus 124 is accomplished by passing a suture 
126 through holes 120 on lower flange ring 106, through tissue annulus 
124, through cuff gasket 128, through holes 118 on upper flange ring 104 
and securely knotting sutures 126 together with suture knot 130. 
FIG. 3C is a top plan view of valve 100. Occluder leaflets 132 are shown in 
lumen area 134 and are movable in mated spherical pivots 135. FIG. 3D is a 
side plan view of valve 100 showing valve 100 attached to heart tissue 
annulus 124. Tissue annulus 124 and cuff gasket 128 fit between flange 
rings 104 and 106, as shown in cross section in FIG. 3D. Cuff gasket 128 
conforms to irregular tissue geometry that may result from removal of the 
existing valve, valve calcification or other causes, and as a gasket to 
reduce perivalvular leakage. Tissue annulus 124 engages the valve outer 
diameter 112 snugly when valve 100 is inserted to create a seal and reduce 
blood leakage. Sutures 126 secure valve 100 to tissue annulus 124. In one 
embodiment, these same sutures 126 are used to maintain flange rings 104 
and 106 in abutting contact with rim 110. 
FIGS. 1A through 3D are shown wit-h a lower flange ring. Alternatively, it 
is within the contemplation of the invention to not provide the lower 
flange ring. 
FIGS. 1 through 5 illustrate mitral heart valve embodiments. The 
embodiments are equally applicable to other heart valves. 
In the designs shown in FIGS. 1A through 3C, it is desirable to reduce and 
prevent perivalvular leakage. This may be achieved by including a 
biocompatible gasket made from a soft, compliant material which lies in 
contact with and between the tissue annulus and the upper or lower flange 
rings. This thin layer of material acts as a pad to conform to irregular 
tissue contours which result from removal of the existing valve, heart 
disease and calcification and is intended to minimize perivalvular 
leakage. This component of the design is described below in greater 
detail. 
FIG. 4 is a cross-sectional view of a mechanical heart valve 150 having a 
single orifice flange or flange ring 152 in accordance with another 
embodiment. Valve 150 includes orifice body 154 defining a lumen 156 
therethrough. Orifice flange 152 is formed integral with orifice body 154 
and includes suture hole 158 extending therethrough. A biocompatible 
fabric flange gasket 160, such as polyester, extends around valve annulus 
162, as shown in FIG. 4. Flange ring 164 extends around annulus 162 and 
provides a suture receiving element similar to the flange rings of valves 
10, 50, and 100 described above. A suture 1)6 extends through suture hole 
158 of orifice flange 152, heart tissue annulus 168 and flange ring 164, 
and thereby attaches valve 150 to heart tissue annulus 168. A suture knot 
170 secures suture 166 to orifice flange 152. Fabric ring 160 acts as a 
gasket to prevent and reduce perivalvular leakage. Further, flange ring 
164 prevents suture 166 from being drawn through or into heart tissue 
annulus 168. In embodiments where flange ring 164 is made rigid (see 
valves 10, 50 and 100 discussed above), the suture 166 can be drawn tight 
thereby compressing heart tissue annulus 168 to further reduce the 
likelihood of perivalvular leakage. 
Attachment to heart tissue of the valves described herein may be through 
any suitable means. A number of techniques will be described in greater 
detail. FIG. 5 is a cross-sectional view of valve 10 shown in FIGS. 1A 
through 1D which includes gaskets 180 and 182 to reduce perivalvular 
leakage. As shown in FIG. 5, a gasket 180 is provided adjacent orifice 
flange (or flange ring) 14. Similarly, gasket 182 is adjacent flange ring 
16. A suture 184 extends through flange ring 16, gasket 182, heart tissue 
annulus 186, gasket 180 and suture hole 20 in orifice flange 14. A suture 
knot 188 secures suture 184 to valve 10. Gaskets 180 and 182 help seal the 
annulus of valve 10 to heart tissue annulus 186. Gaskets 180 and 182 will 
tend to conform to irregular heart tissue, for example calcified tissue 
irregularities. Gaskets 180 and 182 can be supplied to a surgeon in a 
variety of shape, size and thickness configurations so an appropriate 
gasket may thus be chosen for each individual procedure. FIG. 5 also shows 
orifice cap 190 having a plurality of plugs 192. In one embodiment, cap 
190 is ring-shaped having a plurality of plugs 192 aligned with suture 
holes 20. Plugs 192 are inserted into suture holes 20 and locked in place 
by enlarged tip 194. Plug 192 helps secure suture 184 in hole 20 thereby 
preventing suture 184 from being pulled back through hole 20. 
FIG. 6 is a cross-sectional view showing heart valve 200. Valve 200 
includes orifice 202 forming lumen 204 therethrough. Orifice 202 provides 
annulus 206 and annulus 208 separated by rim 210. Valve 200 is attached to 
heart tissue annulus 212 using flange ring 214 and flange ring 216. A 
suture 218 extends through flange ring 214, heart tissue annulus 212, 
gasket material 220 and flange ring 216, and is secured to flange ring 216 
with suture knot 222. Flange ring 216 includes cantilevered spring 224 
which abuts rim 210. Cantilevered spring 224 allows valve 200 to be 
implanted as a two-piece valve. After suturing flange rings 214 and 216 to 
the heart tissue annulus 212, orifice 202 can be snapped into place and 
locked between cantilevered spring 224 and flange ring 214. This may ease 
the implantation of small valves by allowing increased visibility of the 
operating field during suturing. Additionally, this configuration allows 
easy viewing and access of the ventricular side of the heart tissue 
annulus 212 prior to insertion of orifice 202. 
FIG. 7 shows a cross-sectional view of flange ring 240 having chamfered 
slot 242 and suture hole 244. Flange ring 240 is adapted for securing a 
suture 246 without requiring a suture knot. A ball or cylinder 248 fits in 
chamfered slot 242. As suture 246 is pulled through opening 244, ball 248 
is pulled deeper into chamfered slot 242 thereby squeezing suture 246 
against flange 240. However, if suture 246 is pulled in the opposite 
direction, suture 246 meets with no resistance from ball 248. 
FIG. 8 is a cross-sectional view of flange 250 including spring 252 over 
suture opening 254. Spring 252 presses against suture 256 thereby locking 
suture 256 to flange 250. These embodiments provide reduced implantation 
time because a surgeon is not required to knot the sutures. These 
techniques are well suited for use with the stiff orifice flanges and 
flange rings described herein. 
A mechanical valve set forth herein in a typical implantation will have a 
portion which sits subannular, a portion which fits intra-annular and a 
portion which resides supra-annular relative to the heart tissue annulus. 
In general, the heart tissue annulus fits between the two flanges, and the 
valve extends both subannularly and supra-annularly. The embodiments set 
forth herein eliminate the sewing ring or suture cuff currently used, the 
manufacture of which is labor intensive. The sewing cuff can be replaced 
by a separate gasket which can be easily mass produced, reducing 
manufacturing cost and offering the surgeon a broader range of gasket 
styles to match individual case scenarios. Further, the gaskets set forth 
reduce perivalvular leakage. Additionally, the flanges can be adapted for 
use with suture attachment techniques which do not require a suture knot. 
Further, the embodiments may allow enlarging the lumen area thus offering 
less restriction to blood flow through the orifice. 
Although the present invention has been described with reference to 
preferred embodiments, workers skilled in the art will recognize that 
changes may be made in form and detail without departing from the spirit 
and scope of the invention.