|Publication number||US20070129710 A1|
|Application number||US 11/651,268|
|Publication date||Jun 7, 2007|
|Filing date||Jan 9, 2007|
|Priority date||Jul 28, 2003|
|Also published as||EP1648334A2, US7204255, US20050027337, WO2005011473A2, WO2005011473A3|
|Publication number||11651268, 651268, US 2007/0129710 A1, US 2007/129710 A1, US 20070129710 A1, US 20070129710A1, US 2007129710 A1, US 2007129710A1, US-A1-20070129710, US-A1-2007129710, US2007/0129710A1, US2007/129710A1, US20070129710 A1, US20070129710A1, US2007129710 A1, US2007129710A1|
|Inventors||Robert Rudko, Mark Tauscher, Richard Yeomans|
|Original Assignee||Rudko Robert I, Tauscher Mark R, Yeomans Richard P Jr|
|Export Citation||BiBTeX, EndNote, RefMan|
|Referenced by (2), Classifications (11)|
|External Links: USPTO, USPTO Assignment, Espacenet|
This is a Divisional application of U.S. patent application Ser. No. 10/628,794, filed on Jul. 28, 2003, hereby incorporated by reference herein.
This invention relates to endovascular aortic valve replacement.
Currently, replacement of a malfunctioning heart valve is accomplished by a major open-heart surgical procedure requiring general anesthesia, full cardio-pulmonary bypass with complete cessation of cardio-pulmonary activity, and a long period of hospitalization and recuperation. In most cases, the native valve is resected (cut-out) and the replacement valve then installed.
As an alternative to open heart surgery, those skilled in the art have attempted to devise systems for endovascular heart valve replacement to overcome the disadvantages associated with open-heart surgery. U.S. Pat. No. 5,370,685, for example, discloses a procedure device capsule connected to a tube and delivered to the site via a guide wire introduced in the femoral artery of a patient. The device capsule houses an expandable barrier attached to balloon segments. Once the guide wire is removed and the barrier is expanded, a tissue cutting blade assembly is advanced in the tube and rotated by a DC motor to resect the existing valve. The barrier traps any debris cut by the tissue cutting blade assembly. Tissue is then suctioned out via the tube. Next, the cutting blade assembly is removed, the barrier balloons are deflated, and the barrier is brought back into the capsule and the capsule itself is removed.
Then, a valve introducer capsule is advanced to the site. The capsule houses a replacement valve and includes a pusher disk and inflatable balloon segments. After the balloon segments are inflated, the pusher disk pushes the replacement valve into position and a mounting balloon is used to expand the replacement valve and to secure it in place. Then, the introducer capsule is removed. The '685 patent is hereby incorporated herein. See also U.S. Pat. Nos. 5,545,214; 6,168,614; 5,840,081; 5,411,552; 5,370,685; and published Patent Application No. U.S. 2002/0058995 A1. These patents are also incorporated herein.
The problem with such a system is that the tissue cutting blade assembly is less than optimal and does not provide very precise cutting especially given the fact that the valve is made of both soft and hard tissue because it is heavily calcified or contains fibrotic tissue. Thus, the blades may buckle or bind as they alternately contact soft and hard tissue.
It is also presumed that pressure must be exerted on the blades. Control of this pressure and the control of the rotation rate, however, is not disclosed in the '685 patent. There is no margin for error in the resection procedure. If too much tissue is cut in certain areas, for example, the aorta can be permanently damaged. Moreover, the existing valve typically fails because of calcification of the valve resulting in stenosis or insufficiency. Using cutting blades for valve resection and an improper orientation or improper pressure on the cutting blades or the wrong rate of rotation can result in too little or too much tissue removal and/or imprecise cutting and/or blade buckling or binding as the blades alternately contact soft and hard (calcified) tissue.
Other relevant art includes the following, also included herein by this reference. Published Patent Application No. U.S. 2002/0095116 A1 discloses an aortic filter, an artery filter, and a check valve attached to the distal end of a canula for resecting an aortic valve from within the aorta. The mechanism for resecting the aortic valve, however, is not disclosed. U.S. Pat. No. 6,287,321 also discloses a percutaneous filtration catheter. U.S. Pat. No. 5,554,185 discloses an inflatable prosthetic cardiovascular valve but does not disclose any specific method of resecting the existing or native valve.
U.S. Pat. No. 6,425,916 discloses a percutaneous approach with a valve displacer for displacing and holding the native valve leaflets open while a replacement valve is expanded inside the native valve. In this way, the native valve does not need to be resected. In many cases, however, such a procedure can not be carried out due to the poor condition of the native valve. And, because the native valve occupies space, the largest aperture possible by the replacement valve may not provide sufficient blood flow.
U.S. Pat. Nos. 6,105,515 and 6,485,485, also incorporated here by this reference, disclose various expandable laser catheter designs.
It is therefore an object of this invention to provide a more precise tissue cutting apparatus for endovascular heart valve replacement.
It is a further object of this invention to provide such a tissue cutter which is more effective than prior art blade type tissue cutters.
It is a further object of this invention to provide a tissue cutter which provides effective resection even if the valve is heavily calcified or has fibrotic tissue.
It is a further object of this invention to provide such a tissue cutter which does not require a high rate of rotation.
It is a further object of this invention to provide such a tissue cutter which eliminates the need for precise pressure control.
The invention results from the realization that a more effective and more precise tissue cutting apparatus for endovascular heart valve replacement is effected by the use of an optical fiber inside a deflectable tip catheter and an expandable balloon which registers the assembly inside the heart for resection by laser ablation as the deflectable tip steers the distal end of the optical fiber.
This invention features an endovascular tissue removal device comprising a lumen including a distal steerable tip portion extending from a joint portion, registration means for holding the joint portion fixed in place in the vasculature, and a source of ablation energy in communication with the lumen whereby tissue can be resected by ablation energy as the tip portion is steered within the vasculature.
In the preferred embodiment, the registration means includes an inflatable balloon about the joint portion, the source of ablation energy is a laser, the distal steerable tip portion includes a deflectable tip catheter, and there is an optical fiber inside the deflectable tip catheter and connected to the laser. The device may further include an expandable barrier for trapping any debris resected. The device, in one embodiment, includes an expandable mechanism inflatable on the ventricular side of the valve for supporting the leaflets of the valve. An absorptive surface on the expandable mechanism absorbs ablation energy. Typically, the expandable mechanism is a balloon.
An endovascular tissue removal device in accordance with this invention features a lumen including a distal steerable tip portion extending from a joint portion, an inflatable balloon about the joint portion for registering the joint portion fixed in place in vasculature, and a source of ablation energy in communication with the lumen whereby tissue can be resected by ablation energy as the tip portion is steered within the vasculature.
A lumen includes a distal steerable tip portion extending from a joint portion, registration means holds the joint portion fixed in place in vasculature, and an optical fiber is disposed within the lumen and steerable by the distal steerable tip portion and connected to a source of ablation energy to resect tissue as the tip portion is steered within the vasculature.
In the preferred embodiment, the endovascular heart removal device of this invention includes a catheter including a deflectable tip, a laser source, an optical fiber within the catheter connected to the laser source, and an inflatable balloon for registering the deflectable tip in vasculature to resect a heart valve with laser energy as the deflectable tip portion is used to steer the distal end of the optical fiber within vasculature.
A method of resecting a valve, the method in accordance with this invention includes endovascularly introducing a lumen with a distal steerable tip portion to a position proximate a valve to be resected; registering the lumen in place in the vasculature; directing ablation energy through the lumen; and steering the distal steerable tip portion to resect the valve. In one example, an expandable mechanism is positioned on the ventricular side of the valve and inflated to support the leaflets of the valve during resection.
Other objects, features and advantages will occur to those skilled in the art from the following description of a preferred embodiment and the accompanying drawings, in which:
Aside from the preferred embodiment or embodiments disclosed below, this invention is capable of other embodiments and of being practiced or being carried out in various ways. Thus, it is to be understood that the invention is not limited in its application to the details of construction and the arrangements of components set forth in the following description or illustrated in the drawings.
But, the prior art teaches resection of the native valve tissue by tissue cutter 40,
As shown in
The problem is so profound that some skilled in the art have attempted to eliminate native valve resection and instead theorize that a prosthetic valve can be expanded directly within native valve 12 (or 14) using a valve displacer to hold the native valve open. As delineated above, however, due to the condition of the native valve, such a procedure is not always possible or effective.
In the subject invention, more precise tissue cutting is effected even if native valve 12,
A complete system would include an expandable barrier such as barrier 30,
In this way, the problems associated with prior art blade type tissue cutters are eliminated and tissue cutting is far more precise by the use of optical fiber 110 within deflectable tip catheter 100 and expandable balloon 116 which registers the assembly inside the heart for resection by laser ablation as the deflectable tip portion steers the distal end of optical fiber 110.
A more complete system is shown in
Although specific features of the invention are shown in some drawings and not in others, this is for convenience only as each feature may be combined with any or all of the other features in accordance with the invention. The words “including”, “comprising”, “having”, and “with” as used herein are to be interpreted broadly and comprehensively and are not limited to any physical interconnection. Moreover, any embodiments disclosed in the subject application are not to be taken as the only possible embodiments.
Other embodiments will occur to those skilled in the art and are within the following claims:
|Citing Patent||Filing date||Publication date||Applicant||Title|
|US7846108||Dec 10, 2008||Dec 7, 2010||Vivant Medical, Inc.||Localization element with energized tip|
|US7875024||Feb 8, 2005||Jan 25, 2011||Vivant Medical, Inc.||Devices and methods for cooling microwave antennas|
|U.S. Classification||606/7, 606/27|
|International Classification||A61B18/24, A61B17/22, A61B18/18, A61B17/00|
|Cooperative Classification||A61B2017/00243, A61B2017/22069, A61B18/24, A61B2017/22097|