The assignee for this patent application is
Reporters obtained the following quote from the background information supplied by the inventors: "The present invention relates to heart valve replacement and, in particular, to collapsible prosthetic heart valves. More particularly, the present invention relates to collapsible prosthetic heart valves having a smaller, more consistent diameter.
"Prosthetic heart valves that are collapsible to a relatively small circumferential size can be delivered into a patient less invasively than valves that are not collapsible. For example, a collapsible valve may be delivered into a patient via a tube-like delivery apparatus such as a catheter, a trocar, a laparoscopic instrument, or the like. This collapsibility can avoid the need for a more invasive procedure such as full open-chest, open-heart surgery.
"Collapsible prosthetic heart valves typically take the form of a valve structure mounted on a stent. There are two types of stents on which the valve structures are ordinarily mounted: a self-expanding stent and a balloon-expandable stent. To place such valves into a delivery apparatus and ultimately into a patient, the valve must first be collapsed or crimped to reduce its circumferential size.
"When a collapsed prosthetic valve has reached the desired implant site in the patient (e.g., at or near the annulus of the patient's heart valve that is to be replaced by the prosthetic valve), the prosthetic valve can be deployed or released from the delivery apparatus and re-expanded to full operating size. For balloon-expandable valves, this generally involves releasing the valve, assuring its proper location, and then expanding a balloon positioned within the valve stent. For self-expanding valves, on the other hand, the stent automatically expands as the sheath covering the valve is withdrawn.
"Despite the various improvements that have been made to the collapsible prosthetic heart valve delivery process, conventional delivery devices, systems, and methods suffer from some shortcomings. For example, in conventional prosthetic valves a cuff and leaflets are attached to the stent, interfering with the full collapsibility of the stent. The cuff and leaflets may include excess tissue material not necessary for function. This excess tissue material unduly increases the crimp profile of the valve assembly. It is believed that a large crimp profile may be partially responsible for vascular injury during delivery of prosthetic heart valves. Moreover, slack in the cuff and/or valve assembly reduces the chronic outward radial force, leading to inferior valve performance.
"There therefore is a need for further improvements to the devices, systems, and methods for transcatheter delivery of collapsible prosthetic heart valves, and in particular, self-expanding prosthetic heart valves. Among other advantages, the present invention may address one or more of these needs."
In addition to obtaining background information on this patent application, VerticalNews editors also obtained the inventors' summary information for this patent application: "A method of assembling a prosthetic heart valve may include providing a collapsible and expandable stent having an annulus section and an aortic section, the annulus section having a first annulus diameter in a relaxed condition and a second annulus diameter less than the first annulus diameter in a collapsed condition. A constraint may be applied to the stent to constrain the annulus section to a predetermined annulus diameter between the first annulus diameter and the second annulus diameter. At least one of a cuff or a plurality of leaflets may be assembled to the constrained annulus section to form a prosthetic heart valve and the constraint may be removed from the stent after the assembly step.
"In some examples, the aortic section has a first aortic diameter in the relaxed condition and a second aortic diameter less than the first aortic diameter in the collapsed condition, and the step of applying the constraint constrains the aortic section to a predetermined aortic diameter between the first aortic diameter and the second aortic diameter.
"The constraint may include a first suture tied to the annulus section of the stent to constrain the diameter of the annulus section to the predetermined annulus diameter and a second suture tied to the aortic section of the stent to constrain the diameter of the aortic section to the predetermined aortic diameter. The predetermined annulus diameter may be between about 85% and about 95% mm of the first annulus diameter. The constraint may include at least one drawstring to constrain the diameter of the annulus section. The at least one drawstring may include a first suture tied to the annulus section of the stent to constrain the diameter of the annulus section to the predetermined annulus diameter.
"In some examples, the removing step may include cutting the first suture to release the annulus section to an unconstrained annulus diameter between the predetermined annulus diameter and the first annulus diameter. The constraint may include at least one ring disposed about a circumference of the stent to constrain the diameter of the stent. The constraint may also include a first ring disposed about the annulus section of the stent and a second ring disposed about the aortic section of the stent. The first ring and the second ring may be coupled together by a helical portion.
"In some examples, further comprising rotating the constraint with respect to the stent to facilitate the assembling step. The constraint may include a cylindrical body having a proximal opening, a distal opening, a lumen defined between the proximal opening and the distal opening, and at least one window in the body configured and arranged to permit assembly of the prosthetic heart valve therethrough. The at least one window may include three triangular windows evenly spaced about the circumference of the constraint. The constraint may include a cone portion at the distal opening. Cutouts in the body may be spaced to facilitate assembly of the heart valve. The constraint may further include at least two rings and a plurality of angled struts coupled to the at least two rings, the plurality of angled struts outlining a plurality of triangles.
"A method of assembling a prosthetic heart valve includes providing a collapsible and expandable stent having an annulus section and an aortic section, the annulus section having a first annulus diameter in a relaxed condition and second annulus diameter less than the first annulus diameter in a collapsed condition. The stent may be cooled to a temperature below a predetermined temperature at which the diameter of the annulus section decreases to a predetermined diameter between the first and second diameters. At least one of the cuff or a plurality of leaflets may be assembled to the cooled stent to form a prosthetic heart valve.
"In some examples, the step of cooling the stent may include placing the stent within a cooled air box. The predetermined temperature may be below the Austenitic Finish temperature.
BRIEF DESCRIPTION OF THE DRAWINGS
"Various embodiments of the present invention are described herein with reference to the drawings, wherein:
"FIG. 1 is a partial side elevational view of a prosthetic heart valve including a stent and a valve assembly having a cuff and leaflets;
"FIG. 2 is schematic perspective view of a prosthetic heart valve in a cooled air box;
"FIG. 3 is a side perspective view of a fixation device having two rings;
"FIGS. 4A and 4B are side perspective views of fixation devices having two rings coupled to a helical portion;
"FIG. 5A is a side perspective view of a prosthetic heart valve constrained with drawstrings at the annulus section;
"FIG. 5B is a side perspective view of a prosthetic heart valve constrained with drawstrings at the annulus section and the aortic section;
"FIG. 6 is a side perspective view of a fixation device having a cylindrical body and a substantially triangular window;
"FIG. 7 is a side perspective view of a fixation device having a body, a cone portion and multiple windows;
"FIG. 8 is a side perspective view of a fixation device having a body with internal cutouts, and multiple windows;
"FIG. 9 is a side perspective view of a fixation device having a pair of rings and angled struts; and
"FIG. 10 is a side perspective view of a fixation device having three rings and angled struts.
"Various embodiments of the present invention will now be described with reference to the appended drawings. It is to be appreciated that these drawings depict only some embodiments of the invention and are therefore not to be considered limiting of its scope."
For more information, see this patent application: Braido,
Keywords for this news article include: Heart Valves, Cardio Device, Medical Devices, St. Jude Medical Cardiology Division Inc.
Our reports deliver fact-based news of research and discoveries from around the world. Copyright 2014, NewsRx LLC
Most Popular Stories
- 5 Notable Hispanic Technology Executives
- Top Hispanic Tech Companies Push for the Top
- Tesla's Alt-Energy Future Aims for Massive Lithium-Ion Battery Production
- Rand Paul Tops Presidential Straw Poll at Conservative PAC Conference
- Russia, Crimea Discuss Referendum
- China Urges Malaysia Flight Emergency Response
- New Chat App, Yik Yak, Causes Problems for Students
- Gas Prices May Jump from Calif. Emissions Law
- Obama Meets with Ukraine Prime Minister Wednesday
- Visa, MasterCard Team Up to Focus on Payment Security