Prosthesis (i.e. – artificial body members) – parts thereof – or ai – Heart valve – Flexible leaflet
Reexamination Certificate
1998-09-28
2002-01-01
Willse, David H. (Department: 3738)
Prosthesis (i.e., artificial body members), parts thereof, or ai
Heart valve
Flexible leaflet
C623S002150
Reexamination Certificate
active
06334873
ABSTRACT:
FIELD OF THE INVENTION
This invention relates to improvements in heart valves using autologous tissue held in place by anchors and an outer sheath. The heart valve can be constructed intraoperatively within a short time, typically 10 minutes.
BACKGROUND OF THE INVENTION
Several types of heart valves are presently available for use in replacing diseased or malfunctioning heart valves in humans.
One form of heart valve is constructed from animal tissue, typically from bovine or porcine aortic valve tissue. These valves must typically be constructed in a laboratory well in advance of when they will be needed and then stored in an aldehyde solution. Skilled technicians are required to assemble these valves. The valves constructed from animal tissue have relatively short lifetimes. The short lifetimes are caused by two factors. First, there is an antigenic reaction by the body to the animal tissue which causes the tissue to calcify, making it inflexible and more susceptible to failure with time. Second, the tissue is often stored in glutaraldehyde before implantation to try to decrease the antigenic reaction. The aldehyde tends to tan the tissue to a leather-like consistency, which makes it wear out from the repeated stress of opening and closing.
Thus, although these animal tissue valves are widely used, most have to be replaced after about five to ten years. Replacing the valves poses risks to the patient, because a second open heart operation is then needed, with the attendant possibility of problems during the operation.
Mechanical heart valves are also available. These valves are made from hard, non-biological materials such as metals or ceramics. Although the mechanical heart valves are durable, the hard, non-biological surfaces on the valves tend to cause blood clots. The blood clots can cause heart attacks or strokes, and, as a result, patients with mechanical heart valves must take anticoagulant drugs. These drugs can lead to hemorrhagic complications. Also, patients on these drugs require frequent and lifelong laboratory tests of their clotting time.
Another type of heart valve, the autogenous tissue valve, is constructed with the patient's own tissue. A number of patents for autologous tissue heart valves and methods of making autologous tissue heart valves have issued to Autogenics, assignee of this application, including U.S. Pat. Nos. 5,161,955 and 5,326,371.
SUMMARY OF THE INVENTION
This invention provides an improved apparatus and method for constructing an autologous tissue heart valve. A significant factor of the invention is that both the configuration of the autologous tissue and its means for attachment to the frame of the valve prevent deleterious stress on the tissue.
Accurate placement of the autologous tissue is provided by forming pericardium tissue taken from the patient into three separate tissue leaflets, each generally semi-circular shape and having a plurality of tissue anchor holes located along a tissue cusp line. The location of these tissue anchor holes correspond to tissue anchor hooks permanently attached to a tissue mounting frame.
These three leaves of tissue are placed sequentially on the tissue anchor hooks of the tissue mounting frame so as to be located completely around the circumference of the tissue mounting frame. An elastomeric sheath is stretched over the exterior of the tissue mounting frame. This sheath prevents the tissue from coming off the tissue anchor hooks and rests gently on the tissue around the cusp line such that the tissue forms a naturally closed valve.
A significant feature of this invention is that the manner in which the autologous tissue is supported prevents deleterious stress on the tissue. The tissue is thus not clamped between two unyielding members, but rather supported and retained by the combination of anchors mated in tissue anchor holes and the elastomeric sheath engaging a peripheral portion of the tissue leaflets between the elastomeric sheath member and the inner tissue mounting frame.
Another feature of the invention is that the tissue leaflets are formed to include sufficient extra tissue area to provide a physiologically representative coaptation line angle to thereby reduce the stretch in the tissue held in place by the sheath and thus further reduce the stress in the tissue.
REFERENCES:
patent: 2822819 (1958-02-01), Geeraert
patent: 3548418 (1970-12-01), Angell et al.
patent: 3570014 (1971-03-01), Hancock
patent: 3714671 (1973-02-01), Edwards et al.
patent: 3744062 (1973-07-01), Parsonnett
patent: 3755823 (1973-09-01), Hancock
patent: 3983581 (1976-10-01), Angell et al.
patent: 4035849 (1977-07-01), Angell et al.
patent: 4079468 (1978-03-01), Liotta et al.
patent: 4084268 (1978-04-01), Ionescu et al.
patent: 4106129 (1978-08-01), Carpentier et al.
patent: 4172295 (1979-10-01), Batten
patent: 4192020 (1980-03-01), Davis et al.
patent: 4247292 (1981-01-01), Angell
patent: 4291420 (1981-09-01), Reul
patent: 4297749 (1981-11-01), Davis et al.
patent: 4388735 (1983-06-01), Ionescu et al.
patent: 4470157 (1984-09-01), Love
patent: 4490859 (1985-01-01), Black et al.
patent: 4501030 (1985-02-01), Lane
patent: 4605407 (1986-08-01), Black et al.
patent: 4687483 (1987-08-01), Fisher et al.
patent: 4692164 (1987-09-01), Dzemeshkevich et al.
patent: 4725274 (1988-02-01), Lane et al.
patent: 4851000 (1989-07-01), Gupta
patent: 5037434 (1991-08-01), Lane
patent: 5147391 (1992-09-01), Lane
patent: 5163955 (1992-11-01), Love et al.
patent: 5326370 (1994-07-01), Love et al.
patent: 5326371 (1994-07-01), Love et al.
patent: 5423887 (1995-06-01), Love et al.
patent: 5489298 (1996-02-01), Love et al.
patent: 5549665 (1996-08-01), Vesely et al.
patent: 5571174 (1996-11-01), Love et al.
patent: 5571567 (1996-11-01), Shah
patent: 5612885 (1997-03-01), Love
patent: 5653749 (1997-08-01), Love et al.
patent: 5662705 (1997-09-01), Love et al.
patent: 5755782 (1998-05-01), Love et al.
patent: 5843181 (1998-12-01), Jaffe et al.
patent: 5855601 (1999-01-01), Bessler et al.
patent: 5928281 (1999-07-01), Huynh et al.
patent: 5935163 (1999-08-01), Gabbay
patent: 6095968 (2000-08-01), Snyders
patent: 6102944 (2000-08-01), Huynh et al.
patent: 6126686 (2000-10-01), Badylak et al.
patent: 6254636 (2001-07-01), Peredo
patent: 0125393 (1981-10-01), None
patent: 0179562 (1985-09-01), None
patent: 0 179 562 (1986-04-01), None
patent: 21136533 (1983-08-01), None
patent: WO 94/04099 (1994-03-01), None
Degenerative Calcification in Tissue Valves—A Metabolic/Hemodynamic and Immunologic Problem, Love et al., Abstract Published for the First Scientific Meeting of the international Association for Cardiac Biological Implants, Chicago, Apr. 5, 1987.
Dopler and Hemodynamic Characteristics of the Autogenics Bioprosthetic Valve, Khan et al.
Rapid Intraoperative Fabrication of an Autogenous Tissue Heart Value: A New Technique, pp. 691-689, Love, et al., 1986.
Experimental Evaluation of an Autologous Tissue Heart Valve, pp. 232-24, Love et al., J Heart Valve Dis. vol. 1, No. 2, 1992.
A construction technique for minimising valve leaflet fitigue failure in pericardial valves, Life Support Systems, Black, et al., Sep. 1984, Proceedings XI Annual Meeting ESAO, vol. 2 Supplement 1.
A fascia lata mitral valve based on the ‘frustum’ principle, Thorax, 1971, pp. 284-287, Brownlee and Yates.
Editorial Towards Understanding the Pericardium as Valve Substitute, pp. 213-15, Frater and Bodnar, The Journal of Heart Valve Disease 1992.
The flexible stent A new concept in the fabrication of tissue heart valve prostheses, The Journal Of Thoracic And Cardiovascular Surgery, vol. 62, No. 5, pp. 683-689; 693-695, Nov., 1971.
In Vitro Testing of Bioprostheses, vol. XXXIV Trans Am Soc Artif Intern Organs 1988, Reul et al., pp. 1033-1039.
A Method For Preparing And Inserting A Homograft Aortic Valve, The British Journal Of Surgery, B.G. Barratt-Boyes, pp. 847-856.
Replacement of heart valves with frame-mounted tissue grafts, Ionescu et al., Thorax 1974, pp. 56-67.
Frame-mounted tissue heart valves: technique of construction, Bartek, et al., Thorax 1974, pp. 51-55.
A
Hemsley David
Lane Ernest
Tompkins David
Autogenics
Jackson Suzette J.
Knobbe Martens Olson & Bear LLP
Willse David H.
LandOfFree
Heart valve having tissue retention with anchors and an... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Heart valve having tissue retention with anchors and an..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Heart valve having tissue retention with anchors and an... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2871842