Abstract:
An endoluminal catheterization device for providing protection against distal embolization of atherosclerotic debris and thrombi emboli resulting from an endoluminal catheterization procedure. The device is adapted to the new TAVI/PAVI methods to prevent the severe risk of brain embolization and stroke. The embolization protection device may also be an integral part of any other intra-luminal treatment or diagnostic device that may induce embolization, such as a balloon, stent, TAVI or atherectomy.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates generally to the field of angioplasty, and more particularly to angioplasty devices providing protection against embolization. The present application is a Continuation-in-Part of U.S. patent application Ser. No.: 12/758,850 filed Apr. 13, 2010 by the Applicant, the disclosure of which is hereby incorporated by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    Coronary artery disease (CAD) affects almost 1.3 million Americans per year, making it the most common form of heart disease. CAD most often results from a condition known as atherosclerosis, which is the most common form of arteriosclerosis i.e. hardening of the arteries. 
         [0003]    Atherosclerosis occurs when plaque forms inside the arteries. Plaque is made of cholesterol, fatty compounds, calcium and fibrin. As the plaque builds up, the artery narrows, making it more difficult for blood to flow through the arteries. When atherosclerosis occurs in a coronary artery, blood flow to the heart muscle is impeded. In time, the narrowed or blocked artery can lead to angina pectoris, Myocardial Infarct (MI) and possibly death. A similar processes can affect other arteries, such as the carotid, intra-cerebral, and renal arteries, as well as arteries of the upper and lower limbs, leading to stroke, renal failure, hypertension and malfunction of the limbs, depending on artery affected. 
         [0004]    In order to reduce the risk of artery disease and its complications, one option is opening the artery narrowing induced by atherosclerosis, utilizing intra-lumen balloon inflation and/or intra-lumen stent deployment. 
         [0005]    In balloon angioplasty, a guiding catheter is inserted through a small skin incision into an artery and advanced to the origin of the coronary artery. Next, a guide wire is advanced through the guiding catheter into the coronary artery and across the blockage site. Then, a long, thin catheter that has a small balloon on its tip (balloon catheter) is pushed over the guide wire. The balloon is inflated at the blockage site in the artery to flatten or compress the plaque against the artery wall, and is then deflated and withdrawn. Thus, the blockage is removed from at least a portion of the arterial lumen, and blood can flow more freely through the artery. 
         [0006]    Another method for opening plaque blockage is stent deployment. A stent is a small mesh-like tube made of metal. The stent may be pre-crimped over a balloon on the tip of a balloon catheter and pushed over the guide wire (as explained above) to the blockage site, where it is then expanded and deployed by the pressure of the balloon inflation at the narrowed site, and as such, acts as a support or scaffold, keeping the vessel open. Stent procedures are usually used along with balloon angioplasty. The first balloon inflation prepares the narrowed site, and enables stent insertion and deployment by another balloon on which the stent is crimped on. 
         [0007]    Alternatively, a self-expandable stent may be used, which does not require a balloon for deployment. Such stents are made of shape memory metal and are provided with a covering sheath that compresses the stent to a low profile prior to delivery to the deployment site. At the deployment site, the covering sheath is removed, and the shape memory metal enables the stent to regain its full diameter. 
         [0008]    Such procedures may be used to open narrowing in arteries including coronary, carotid, intra-cranial, and renal arteries, and peripheral arteries in the legs and arms. 
         [0009]    Unfortunately, these procedures pose a great risk to the patient as emboli, generated by the balloon inflation or stent deployment that crush the frail atherosclerotic plaque, or thrombotic material, may be released during them. Once released, these emboli have a high likelihood of getting lodged into the smaller vessels at a point of constriction downstream of their release point, causing the vessels to become occluded and preventing blood flow. 
         [0010]    These adverse events may cause severe damage to the treated organ like myocardial infarction, stroke, renal failure or limb malfunction. 
         [0011]    There are several known embolization protection devices based mainly on an additional small proximal or distal occluding balloon with some debris removal system, or a small filter attached to the guide wire with deployment and retrieval systems. 
         [0012]    Examples of known embolization protection devices, include: 
         [0013]    U.S. patent application Ser. Nos. 10/348,137, 11/387,366, 11/566,473 to Wholey et al; 
         [0014]    U.S. patent application Ser. Nos. 11/763,118, 10/997,803 to Sachar et al; 
         [0015]    U.S. patent application Ser. No. 11/271,653 to Blix et al; 
         [0016]    U.S. patent application Ser. No. 09/952,375 to Fischell et al; and 
         [0017]    U.S. patent application Ser. No. 09/845,162 to Wahr. 
         [0018]    The above-mentioned devices have many limitations. The occluding balloon-based type induces ischemia since the occluding balloon stops the distal blood flow for a relatively long period. Moreover, the need for a special debris extraction catheter prolongs the procedure and increases its complexity. 
         [0019]    The over-the-wire filter devices have a special guide wire with inferior crossing ability compared to the regular wires. The extra delivery sheath covers the filter prior to its deployment, increasing the wire profile, reducing its crossing ability and because of its larger size, may cause embolization. There is also difficulty delivering the filter to a proper site distally to the lesion and difficulty in maintaining its position during the procedure. The need for another retrieval system prolongs the whole procedure time. 
         [0020]    It is no wonder that several clinical randomized studies showed that in a group of patients in which distal embolization protection devices were used, the overall adverse events were significantly higher than in the control group where such devices were not applied. 
         [0021]    Therefore, there is a need for a new embolization protection device, which is an integral part of the intra-lumen device, which will decrease the risks of distal embolization during use of intra-lumen devices. 
         [0022]    Trans Luminal Aortic Valve Implantation (TAVI) is a novel therapy which may be used as an alternative to standard surgical aortic valve replacement. The TAVI procedure is performed on the beating heart using catheterization methods without the need for a Sternotomy or a Cardiopulmonary Bypass. Currently, two devices are CE marked and the procedure may be performed via the transfemoral, or subclavian approaches in which the catheter carrying the valve is advanced retrogradlly into the aorta and the artificial valve is positioned at the native aortic valve annulus. 
         [0023]    Another approach is the Transapical method which combines minimally invasive surgery and catheterization. The surgeon performs a small incision at the heart apex, through it, a catheter carrying the valve is advanced anterogradlly and the artificial valve is positioned at the native aortic valve annulus. This Anterograde method is also called PAVI (Percutaneous Aortic Valve Implantation). This new field of interventional cardiology is growing rapidly and there are many companies developing new TAVI/PAVI devices. One major drawback of this new technique is multiple emboli dislodgment from the artificial valve deployment site which is usually heavily calcified. Brain MRI studies showed some degree of emboli into the brain in as many as about 70% of the TAVI cases. 
       SUMMARY OF THE INVENTION 
       [0024]    Accordingly, it is a principal object of the present invention to overcome the limitations of prior art embolization protection devices by providing a distal embolization protection component as an integral part of an Endo-luminal catheterization device, and a simple deployment/retrieval method that does not change or interfere with the current Endo-luminal Transcatheter technique, while trapping any emboli that are released, and allowing blood to continue flowing without interference during the Endo-luminal catheterization procedure. 
         [0025]    In accordance with a preferred embodiment of the present invention, there is provided an Endo-luminal catheterization device for providing protection against distal embolization of atherosclerotic debris and thrombi emboli resulting from an endoluminal catheterization procedure, said device comprising: 
         [0026]    an endoluminal dilatation component mounted on a shaft, said shaft having at least one lumen; a flexible filter integrally mounted on said shaft; and 
         [0027]    a thin retraction filament extending through said at least one lumen in said shaft and emerging from an opening in said shaft, said retraction filament being attached to said flexible filter for controlling deployment and collapsing of said filter, 
         [0028]    wherein said flexible filter, when deployed, traps said atherosclerotic debris and thrombi emboli thus allowing blood flow to continue without interference during said endoluminal catheterization procedure. 
         [0029]    In some embodiments, the dilatation component comprises a stent, such as a self-expandable stent. In some embodiments, the dilatation component comprises an angioplasty balloon, which may optionally have a stent crimped over it. 
         [0030]    The purpose of the filter deployment ring is to open the proximal portion of the filter at the beginning of the endoluminal catheterization procedure, such that the filter is opened to the full size of the circumference of the artery at the treatment site. The artery is thus sealed, such that atherosclerotic debris and thrombi emboli released from the plaque during the procedure, are trapped inside the filter. The filter deployment ring is also used also for collapsing the filter at the end of the procedure, to a small profile, with the trapped emboli inside, for enabling retraction of the balloon catheter with the attached filter as one unit. 
         [0031]    The present invention is designed for equipping any endo-luminal device known in the art including use of guidewires and standard balloon inflation-deflation methods such as a TAVI, balloon angioplasty device, stent, atherectomy, or any other intra-luminal treatment or diagnostic device that may induce embolization, with an integrated embolization protection component, positioned downstream to the treatment device. The integrated embolization protection component relinquishes the need for extra manipulation, hardware or overall procedure time. 
         [0032]    The apparatus, including the treatment and protection components, is advanced to the lesion site, there the protection component is deployed before the balloon/stent/TAVI is deployed. Since these two elements are attached to the same catheter they are fixed together without axial movement, thus preventing movement-induced complications. The protection deployment and retrieval are very fast and easy to operate as will be shown in detail. 
         [0033]    When the dilatation component, such as a balloon, and/or stent compresses and crushes the plaque impeding blood flow, pieces of the plaque are released into the bloodstream and can become lodged in smaller vessels downstream to the treatment site, and block them. To avoid such a scenario, a filter is connected to the dilatation component, downstream to it, and traps any emboli that are released, while allowing blood to continue flowing without interference. 
         [0034]    According to a further embodiment of the present invention, the current distal embolization protection device is adapted to the new TAVI/PAVI methods to prevent the severe risk of brain embolization and stroke. 
         [0035]    In accordance with some embodiments of the present invention, the filter deployment ring is connected to a thin retraction filament extending through a lumen in the shaft and emerging from an opening in the shaft, distal to the dilatation component, to avoid its entrapment by the dilatation component. 
         [0036]    The retraction filament may optionally extend through a lumen which is also an inflation fluid lumen for a balloon. Alternatively, the retraction filament may extend through a dedicated lumen within the shaft. 
         [0037]    In accordance with a second embodiment of the present invention, the retraction filament that is attached to the filter deployment ring, emerges from an opening in the shaft, proximal to an angioplasty balloon, and thereby the retraction filament runs over the entire length of the balloon. The device for a blood vessel angioplasty balloon, according to this embodiment, cannot have a stent pre-crimped over it because the retraction filament and filter can get tangled with a stent, if it were there, at the stage of the device withdrawal. 
         [0038]    According to some embodiments of the present invention, the filter deployment ring is tightened by pulling the retraction filament connected to the filter deployment ring. The tightened filter deployment ring causes the filter to close, containing in it trapped atherosclerotic debris and thrombi emboli. 
         [0039]    According to an alternative embodiment of the present invention, the filter is composed entirely of a memory metal such as Nitinol, and as such, may be deployed and closed without using the filter deployment ring. 
         [0040]    According to some embodiments, the device of the present invention further comprises a separate retraction filament tube proximal to the dilatation device, and joining the hollow shaft, wherein the retraction filament extends through the shaft, and a locking device enabling and disabling forward and backward movement of the retraction filament, wherein the locking device locks the retraction filament onto the retraction filament tube through which the retraction filament passes. 
         [0041]    According to some embodiments, wherein the dilatation device comprises a balloon, the device further comprises a balloon inflation/deflation device configured as a syringe having a plunger proximal to the shaft, and connected to the shaft via an inflation tube, wherein the balloon inflation/deflation device injects inflation fluid through the inflation tube into the balloon for inflation, and withdrawing fluid from the balloon for deflation. 
         [0042]    Optionally, the balloon is reversibly and repeatedly inflatable. 
         [0043]    According to some embodiments, the filter deployment ring is deployed by unlocking the locking device and thereby releasing the thin retraction filament connected to the filter deployment ring, such that the ring returns to its original shape by memory. 
         [0044]    According to some embodiments, the device of the present invention further comprises a safety stopper for ensuring that deployment of the filter occurs before balloon inflation, wherein the safety stopper is attached to the retraction filament and is situated at the connection point of the inflation tube with the shaft, thus blocking the entrance of inflation fluid for inflating the balloon, when the retraction filament is pulled and the filter is not yet deployed. 
         [0045]    According to some embodiments, the safety stopper is pushed forward with the forward movement of the retraction filament when deploying the filter, and the stopper is then removed from the connection point of the inflation tube to said shaft so that said inflation fluid is allowed to flow through the shaft and inflate the balloon. 
         [0046]    According to some embodiments, the shaft is wider in diameter beyond the connection point of the inflation tube to the shaft, for the purpose of accommodating the safety stopper. 
         [0047]    According to some embodiments, the device further comprises a bulbous area formed in the shaft situated distally to the wider section of the shaft, wherein said bulbous area is large enough to contain the safety stopper once the filter is deployed and allow fluid to flow through it, and wherein distally to the bulbous area the shaft continues at a regular width. 
         [0048]    The safety stopper optionally comprises at least one of silicon and rubber. 
         [0049]    According to some embodiments, the length of the wider section of the shaft together with the length of the bulbous area is equal to the distance the retraction filament is pushed forward when the filter is deployed. 
         [0050]    In some embodiments, the balloon is partially surrounded by the filter so that when the balloon is inflated it will further deploy the filter by pushing against it. 
         [0051]    In some embodiments, the device further comprises a stent that is pre-crimped over the balloon, and deployment of the stent is achieved by inflation of the balloon. 
         [0052]    In some embodiments, the diameter of the shaft is approximately two millimeters. 
         [0053]    In some embodiments, the diameter of the balloon before inflation is 0.5 to 0.7 millimeters for coronary balloons, and the diameter of the balloon when inflated is approximately 2 to 4 millimeters, and the diameter of the balloon after deflation is approximately 2.5 millimeters. 
         [0054]    In some embodiments, the diameter of the balloon for coronary stents is 1.1 to 1.5 millimeters. 
         [0055]    In some embodiments, the filter deployment ring comprises a shape memory metal and the flexible filter is made of one of a shape memory metal and a very thin polymeric material. 
         [0056]    In some embodiments, a diameter of the flexible filter before deployment is 0.5 to 1 millimeter in diameter, and the maximal size of said filter at the ring site when it is deployed is 2.5 to 5 millimeters in diameter. 
         [0057]    According to some embodiments, the filter deployment ring comprises a shape memory metal, such as Nitinol. 
         [0058]    According to a further embodiment of the present invention, the current distal embolization protection device is adapted to the new TAVI/PAVI methods to prevent the severe risk of brain embolization and stroke. The embolization protection device may also be an integral part of any other intra-luminal treatment or diagnostic device that may induce embolization, such as a balloon, stent, TAVI or atherectomy. Similar to the coronary protection device the TAVI protection device is an integrated part of the catheter carrying the valve and is attached to the catheter downstream to the artificial valve. Since the TAVI/PAVI protection filter is attached to the catheter downstream to the artificial valve, it can be used for any artificial valve deployment apparatus and method such as a balloon, a self expandable mechanism or any other mechanisms that open the artificial valve at the native valve annulus and fixate it in place. 
         [0059]    In accordance with the preferred embodiments of the present invention there is provided a method for performing an endoluminal catheterization procedure and providing protection against distal embolization resulting in said endoluminal catheterization procedure, said method comprising: 
         [0060]    inserting an endoluminal catheterization device, comprising an endoluminal dilatation component mounted on a shaft, said shaft having a flexible filter mounted integrally thereon and a thin retraction filament extending through said shaft and emerging from an opening in said shaft, said retraction filament being attached to said flexible filter for controlling its deployment and collapse by releasing and pulling said retraction filament; and 
         [0061]    expanding said dilatation component, 
         [0062]    wherein said deployed flexible filter, traps atherosclerotic debris and thrombi emboli that are released from said crushed plaque said expansion of said dilatation component, thus allowing blood flow to continue without interference during said endoluminal catheterization procedure. 
         [0063]    The method for distal embolization protection during an endoluminal catheterization procedure comprises first inserting the device at the treatment site, then deploying the flexible filter by releasing the retraction filament, and then expanding the dilatation component, such as by deploying a self expanding stent, or inflating an angioplasty balloon, which may deploy a stent or a valve-carrying stent, which crushes the plaque. The dilatation balloon is then deflated or the self expanding stent is fully deployed, and by so doing, emboli are released from the plaque and are captured by the deployed filter, while allowing blood to flow freely through it. The procedure ends by pulling the retraction filament which collapses the filter to a small profile with the emboli trapped in it, enabling withdrawal of the device out of the artery. 
         [0064]    A feature of the present invention is a safety stopper, which is optionally substantially conical in shape, and is responsible for assuring that the balloon inflation will occur only once the filter is deployed, and not prior to deployment. The stopper does not allow inflation of the balloon if the filter is not deployed yet. This feature eliminates the possibility of human error, since an error in the order of the deployment of the balloon and filter would cause emboli to be released from the plaque into the blood stream without a filter to trap it. 
         [0065]    Additional features and advantages will become apparent from the following drawings and description. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0066]    For a better understanding of the invention with regard to the embodiments thereof, reference is made to the accompanying drawings, in which like numerals designate corresponding elements or sections throughout, and in which: 
           [0067]      FIG. 1  is a prior art embolization protection device; 
           [0068]      FIG. 2A  shows a perspective view of a dilatation balloon with a distal embolization device; 
           [0069]      FIG. 2B  shows a cross-section along section lines A-A of an embodiment of the device of  FIG. 2A ; 
           [0070]      FIG. 2C  shows a cross-section along section lines A-A of an alternative embodiment of the device of  FIG. 2A ; 
           [0071]      FIG. 3A  shows a balloon inflation/deflation device, a retraction filament and a retraction filament locking device; 
           [0072]      FIG. 3B  shows the device of  FIG. 3A  with a bulbous modification on a shaft for accommodating a safety stopper; 
           [0073]      FIG. 3C  shows a safety stopper blocking balloon inflation; 
           [0074]      FIG. 3D  shows the safety stopper allowing balloon inflation; 
           [0075]      FIG. 4  shows a dilatation balloon with an embolization protection device lodged in a restricted blood vessel; 
           [0076]      FIG. 5  shows the balloon of  Fig.4  with the embolization protection device deployed; 
           [0077]      FIG. 6  shows the balloon of  FIG. 4  inflated; 
           [0078]      FIG. 7  shows the balloon of  FIG. 4  deflated and emboli are captured in the protection device; 
           [0079]      FIG. 8  shows the balloon of  FIG. 4  with the protection device closed and containing released emboli, retracting from the artery; 
           [0080]      FIG. 9  shows the unrestricted blood vessel after treatment; 
           [0081]      FIG. 10  shows a dilation balloon and stent with a distal embolization device lodged in a restricted blood vessel; 
           [0082]      FIG. 11  shows the balloon and stent of  Fig.10  with the embolization protection device deployed; 
           [0083]      FIG. 12  shows the balloon and stent of  FIG. 10  inflated and deployed, respectively; 
           [0084]      FIG. 13  shows the balloon and stent of  FIG. 10  deflated and emboli are captured in the protection device; 
           [0085]      FIG. 14  shows the balloon and stent of  FIG. 10  with the protection device closed and containing released emboli, retracting from the artery; 
           [0086]      FIG. 15  shows the unrestricted blood vessel, with stent, after treatment; 
           [0087]      FIG. 16  shows a perspective view of a dilatation balloon with a distal embolization device, which cannot be used with a stent; 
           [0088]      FIG. 17  shows the dilatation balloon of  FIG. 16 , lodged in a constricted blood vessel; 
           [0089]      FIG. 18  shows the dilatation balloon of  FIG. 16 , with the embolization protection device deployed; 
           [0090]      FIG. 19  shows the dilatation balloon of  FIG. 16 , with the balloon inflated; 
           [0091]      FIG. 20  shows the dilatation balloon of  FIG. 16 , with the balloon deflated and emboli are captured in the embolization protection device; 
           [0092]      FIG. 21  shows the dilatation balloon of  FIG. 16 , with the embolization protection device closed; 
           [0093]      FIG. 22  shows the blood vessel after treatment; 
           [0094]      FIG. 23  shows an alternative embodiment of the device of the present invention, comprising a self expanding stent in a collapsed configuration, with the embolization protection device closed, prior to deployment; 
           [0095]      FIG. 24  shows the device of  FIG. 23  during deployment, wherein the embolization protection device is open; 
           [0096]      FIG. 25  shows the device of  FIG. 23  fully deployed; and 
           [0097]      FIG. 26  shows the device of  FIG. 23  following deployment, with emboli captured within the embolization protection device. 
           [0098]      FIG. 27  shows a perspective view of the Percutaneous Trans Apical (PAVI) approach with the distal embolization device in the closed configuration; 
           [0099]      FIG. 28  shows the PAVI of  FIG. 27  with the distal embolization device in the open configuration; 
           [0100]      FIG. 29  shows a perspective view of the Trans-Femoral (TAVI) approach, with the distal embolization device in the closed configuration; 
           [0101]      FIG. 30  shows the TAVI of  FIG. 29  with the distal embolization device in the open configuration; and 
           [0102]      FIG. 31  shows the TAVI of  FIG. 30  with the balloon deflated and emboli trapped in the filter of the distal embolization device. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0103]    It is a principal object of the present invention to provide health care to an atherosclerosis patient by providing an endoluminal catheterization device comprising an endoluminal dilatation component, such as a balloon, with or without a stent, or a self-expanding stent, or a balloon with a valve-carrying stent, and a flexible filter as an integral part of the angioplasty device. The filter allows blood to flow through it but can also capture and remove from the blood vessel matter such as thrombi or atherosclerotic debris, thus preventing distal embolization. 
         [0104]    Referring now to  FIG. 1 , there is shown a prior art illustration of an embolization protection device. A filter assembly  29  is disposed on a guide wire  28 , distal to a shaft  27 . The filter  29  is not mounted directly on shaft  27 , therefore deployment is more difficult, as explained in the background. This is in contrast to the inventive solution as disclosed in the description of the present invention herein below. 
         [0105]    Referring now to  FIG. 2A , there is shown a perspective view of a device  30  for balloon angioplasty with an embolization protection component according to a preferred embodiment of the present invention. The inventive device  30  comprises a shaft  32 , dilatation balloon  34 , retraction filament  44 , flexible filter  42  and filter deployment ring  40 . In  FIG. 2A , device  30  is depicted mounted on a guide wire  38 . 
         [0106]    Filter  42  may optionally comprise either a shape memory metal, comprising an alloy such as copper-zinc-aluminium-nickel, copper-aluminium-nickel, or nickel-titanium, (for example, Nitinol), or a mesh of very thin polymeric material (for example, ultra high molecular weight polyethylene). The pores of the filter should be of sufficient size to allow free passage of blood cells, while trapping atherosclerotic debris and thrombi emboli. Preferably, the pores are in the range of 30 to 50 microns. 
         [0107]    As seen in  FIG. 2A , dilatation balloon  34  is mounted on shaft  32 , which extends beyond the distal end  35  of balloon  34 . The diameter of shaft  32  is selected to enable deployment of shaft  32  within an artery. For example, the diameter of a shaft for deployment within a coronary artery is approximately 1 millimeter, or less. 
         [0108]    As known in the art of balloon angioplasty, shaft  32  includes a guide wire lumen  39  (shown in  FIGS. 2B and 2C ) from a proximal end of shaft  32  passing through the distal tip of shaft  32 , allowing balloon  34  to be guided along a deployed guidewire to a location in the vasculature. Additionally, as known in the art of balloon angioplasty, shaft  32  also includes an inflation fluid lumen  43  (see  FIGS. 2B and 2C ) providing fluid communication with the inner volume of balloon  34 , allowing inflation and deflation of balloon  34  by introduction or removal of inflation fluid from the inner volume of balloon  34 . 
         [0109]    Device  30  further comprises a retraction filament  44  allowing an operator to collapse and/or release filter deployment ring  40 . Retraction filament  44  passes from the proximal end to the distal end of shaft  32  through a lumen in shaft  32 , which is separate from guide wire lumen  39 , and emerges from an opening  59  in shaft  32  to attach to filter deployment ring  40 . 
         [0110]    As shown in  FIG. 2B , the lumen in shaft  32  through which retraction filament  44  passes may optionally comprise inflation fluid lumen  43 , which is preferably coaxial with guide wire lumen  39 , such that shaft  32  comprises at least two lumens. 
         [0111]    Alternatively, as shown in  FIG. 2C , retraction filament  44  may pass through a dedicated lumen  57  in shaft  32 , isolated from inflation fluid lumen  43 , such that shaft  32  comprises at least three lumens. 
         [0112]    Filter deployment ring  40 , which controls deployment and collapsing of filter  42 , is disposed around the proximal opening of filter  42 , and comprises a shape memory metal such as Nitinol or the like. When retraction filament  44  is pulled so as to tighten filter deployment ring  40 , filter  42  is retained in a collapsed form. 
         [0113]    When retraction filament  44  is released, filter deployment ring  40  returns to its original size and shape, thereby releasing pressure on filter  42 , which is allowed to return to its original conical shape. 
         [0114]    Referring now to  FIG. 3A , there is shown the proximal part of the embolization device  30 . The retraction filament  44  has a handle  50  on its proximal side, for moving the retraction filament  44  back and forth. The retraction filament  44  enters a filament tube  45  at the point where an external locking device  46  is situated. Locking device  46  can be twisted to the right or to the left, to lock and unlock the retraction filament  44  onto filament tube  45 , so that the ability to move the retraction filament  44  back and forth is controlled. Retraction filament  44  covered by filament tube  45  enters shaft  32 . Filament tube  45  may optionally be continuous with retraction filament lumen  57  of  FIG. 2A  or  2 B. 
         [0115]    As part of the device  30  there is provided a balloon inflation/deflation device  48  configured as a syringe having a plunger  47 . The balloon inflation/deflation device  48  is attached to an inflation tube  49  entering shaft  32  at connection point  53 . The inflation device is provided for the purpose of inflating balloon  34  by pushing fluid through tube  49  into balloon  34  via the hollow portion of shaft  32 , and for deflating balloon  34  by withdrawing the fluid from balloon  34 . 
         [0116]    Referring now to FIGS.  3 B- 3 C- 3 D, there is shown the device  30  as shown in  FIG. 3A , modified to accommodate a feature of the invention which is the provision of a safety stopper  51 , which is optionally substantially conical-shaped. The stopper  51  is responsible for ensuring that inflation of the balloon  34  will occur only once filter  42  is deployed, and not prior to deployment. 
         [0117]    To accommodate stopper  51 , section  32 ″ of shaft  32  is provided with a width slightly greater than that of shaft  32 , beyond connection point  53 . A portion of section  32 ″ is shaped to form a bulbous area  55 , and distal to area  55  shaft  32  narrows and continues with the same width of the shaft  32  of  FIG. 3A . 
         [0118]    The following description discloses the mode of operation of safety stopper  51 . 
         [0119]    When retraction filament  44  is pulled, safety stopper  51 , made of rubber, silicon or the like, is situated at connection point  53 , thus blocking the entrance of the inflation fluid into section  32 ″ so that it is not possible to inflate balloon  34 . At this point, filter  42  is closed, since retraction filament  44  is pulled. Once locking device  46  is unlocked and then retraction filament  44  is released and moved forward, it moves the stopper  51  along with it, since they are connected to each other. The stopper  51  moves into section  32 ″, thereby clearing the connection point  53  and allowing fluid to pass therethrough. 
         [0120]    As stated, section  32 ″ is slightly wider beyond connection point  53 , in order for the stopper  51  to fit therein. At the connection point  53 , stopper  51  fits the internal circumference of section  32 ″ of shaft  32 , so it blocks any fluid from entering it. After the wider section  32 ″ of shaft  32 , there is a bulbous shaped area  55 . 
         [0121]    When filter  42  is being deployed, stopper  51  is pushed into area  55  with the forward movement of filament  44 . Bulbous shaped area  55  is large enough to contain stopper  51  and also allow fluid to flow around the stopper  51 , so that when stopper  51  is pushed to bulbous area  55 , shaft  32  is not blocked and balloon  34  inflation is allowed. Distal to bulbous area  55 , the shaft  32  is narrower than section  32 ″. The length of section  32 ″ plus bulbous area  55  is equal to the length that retraction filament  44  is pushed forward to fully deploy filter  42 . 
         [0122]      FIGS. 4-9  illustrate the use of device  30  in an angioplasty procedure. Referring now to  FIG. 4 , there is shown the device  30  at the initial stage of an angioplasty procedure, with non-inflated balloon  34  lodged in a blood vessel  52 , with the balloon  34  positioned where the atherosclerotic plaque  54  is obstructing blood vessel  52 . Filter  42  is collapsed and retained by retraction filament  44 . 
         [0123]    The size in diameter of the non-inflated balloon  34  is 0.5-0.7 millimeters for coronary balloons and 1.1-1.5 millimeters for coronary stents. For intra-cerebral arteries the size of the device is similar. For larger arteries like carotid or peripheral arteries, the size may increase 2-3 fold. 
         [0124]    Referring now to  FIG. 5 , there is shown the device  30  during an angioplasty procedure, when filter  42  has been deployed by unlocking the locking device  46  and releasing the retraction filament  44  through shaft  32 . Once the filament  44  is released, the filter deployment ring  40  surrounding filter  42 , is no longer tightly drawn by the retraction filament  44 , and ring  40  is free to return by memory to its original shape, allowing filter  42  to deploy so as to fit the internal circumference of the blood vessel  52 . Thus filter  42  is released from its collapsed form. 
         [0125]    The size of filter  42  before deployment is 0.5-1 millimeter in diameter. The maximal size of the filter at the ring site when it is deployed is 2.5-5 millimeter in diameter for coronary arteries. 
         [0126]    Referring now to  FIG. 6 , there is shown the device  30  with balloon  34  inflated and therefore pressing against plaque  54  on the walls of blood vessel  52 . The pressure against the plaque  54  causes it to break up into small pieces which when they migrate with the blood flow are called emboli  56  (see  FIG. 7 ). The size of the inflated balloon  34  is approximately 2-5 mm in diameter. 
         [0127]    The sizes of both balloon  34  and filter  42  are 2-5 times larger when the angioplasty procedure is to be done in other arteries like carotid, renal or the peripheral arteries. 
         [0128]    Referring now to  FIG. 7 , there is shown the device  30  with deflated balloon  34 , and the layer of atherosclerotic plaque  54  is reduced because it was crushed and compressed by balloon  34 , while inflated. The still deployed filter  42  traps any emboli  56  that are released from plaque  54 , while allowing blood to continue flowing without interference through the porous filter. These emboli  56 , if allowed to remain in blood vessel  52 , can block smaller vessels downstream to blood vessel  52 , and may cause, for example, infarction or stroke (depending on the treated artery) that may ultimately result in death. 
         [0129]    In accordance with the principles of the present invention, the risk of small vessel downstream blockage by released emboli from the crushed plaque is eliminated since the filter deployment ring  40  seals the artery distally to the treatment site and the emboli flow into the porous filter wherein they are trapped. The present invention thus provides a device that traps the emboli and allows the blood to flow freely during the angioplasty procedure, thus eliminating the risk of downstream blockage and preserving flow during the procedure. 
         [0130]    The balloon  34  inflation-deflation cycle can be repeated as many times as necessary while the filter is still deployed. 
         [0131]    The size of the deflated balloon  34  (after initial inflation) is approximately 1-1.5 mm in diameter for coronary arteries, 2-5 times larger for other arteries. 
         [0132]    Referring now to  FIG. 8 , there is shown device  30  after completion of the angioplasty procedure. The balloon  34  has been deflated and filter  42  is collapsed, containing in it trapped emboli  56 . The filter  42  is closed by pulling retraction filament  44 , and therefore tightening the filter deployment ring  40 , surrounding filter  42 , causing filter  42  to collapse to a small profile of 1-1.5 mm in diameter. 
         [0133]    The device  30  is shown being retracted from vessel  52  (arrow A). 
         [0134]    Referring now to  FIG. 9 , there is shown blood vessel  52 , after removal of the device  30 . As a result of the treatment, the layer of atherosclerotic plaque  54  is reduced and therefore vessel  52  is less obstructed and blood can flow more freely through the vessel. 
         [0135]      FIGS. 10-15  illustrate another preferred embodiment of the device  30  for use in an angioplasty procedure with the addition of a stent. 
         [0136]    Referring now to  FIG. 10 , there is shown an alternative embodiment of the present invention, featuring a dilatation balloon and stent  58  with an embolization protection device  60 . As shown, the device  60  is not yet deployed and is lodged in blood vessel  52  at the initial stage of the procedure. 
         [0137]    Referring now to  FIG. 11 , there is shown the device  60  of  FIG. 10 , with filter  42  deployed, by releasing filter deployment ring  40  by the release of retraction filament  44 . 
         [0138]    Referring now to  FIG. 12 , there is shown the device  60  with balloon  34  inflated, causing stent  58  mounted on balloon  34  to deploy and to expand to fit the circumference of constricted vessel  52  and crush against plaque  54  on the walls of blood vessel  52 , and thereby open the plaque narrowing the artery. During this process the plaque  54  is broken into small pieces called emboli  56 . 
         [0139]    Referring now to  FIG. 13 , there is shown the device  60 , with balloon  34  deflated, thus releasing emboli  56  from plaque  54  flowing downstream to balloon  34  and getting trapped by deployed filter  42 . The porous filter  42  allows blood to flow through it and therefore does not block the blood flow. 
         [0140]    Referring now to  FIG. 14 , there is shown the device  60  with filter  42  closed, containing trapped emboli  56  in it. The filter  42  is closed by pulling retraction filament  44  which in turn pulls filter deployment ring  40  which is disposed around proximal opening of filter  42 . The filter  42  collapses into a small profile, as in the first embodiment ( FIG. 8 ). In this embodiment, the small profile of the closed filter  42  is essential so as to avoid getting entangled with stent  58  when it is withdrawn from vessel  52 , through deployed stent  58 . 
         [0141]    The device  60  is retracted from blood vessel  52 , as indicated by arrow A. 
         [0142]    Referring now to  FIG. 15 , there is shown the stent  58  deployed at the plaque  54  site, after treatment, thus keeping the treatment site open. 
         [0143]    Referring now to  FIG. 16 , there is shown a perspective view of a device  70  for balloon angioplasty according to a preferred embodiment of the present invention. The device is meant only for a balloon without a stent, in an alternative to the embodiment of  FIG. 2 . 
         [0144]    The retraction filament  44 ′ is released from an opening  59  in shaft  32 ′ proximal to balloon  34 ′, and is attached to a thin metal memory filament and continues all the way to filter  42 ′ which is distal to balloon  34 ′, where it forms a ring and surrounds it as described in  FIG. 2 . Filter  42 ′ surrounds a portion of the distal end of balloon  34 ′, so that when balloon  34 ′ is inflated it further deploys filter  42 ′ by pushing against it. 
         [0145]    Referring now to  FIG. 17 , there is shown device  70  lodged in blood vessel  52 ′, in the initial stage of the angioplasty procedure, as described in  FIG. 4 . 
         [0146]    Referring now to  FIG. 18 , there is shown device  70  with filter  42 ′ deployed, prior to balloon  34 ′ inflation. 
         [0147]    Referring now to  FIG. 19 , there is shown device  70  with balloon  34 ′ inflated. Since the balloon  34 ′ is partially surrounded by the filter  42 ′, the balloon  34 ′ comes into contact with filter  42 ′ as it is inflated, and this inflation further deploys filter  42 ′. 
         [0148]    Referring now to  FIG. 20 , there is shown balloon  34 ′ deflated, thereby releasing emboli particles  56  from the crushed plaque  54 ′ which are trapped in still-deployed filter  42 ′, with filter  42 ′ allowing blood to flow through it so as not to obstruct the blood flow. 
         [0149]    Referring now to  FIG. 21 , there is shown filter  42 ′ collapsed, with emboli  56  trapped within, being withdrawn from vessel  52 ′ (arrow A). 
         [0150]    Referring now to  FIG. 22 , there is shown blood vessel  52 ′ having dilated plaque  54 ′ after successful balloon angioplasty treatment. 
         [0151]    Referring now to  FIGS. 23 to 26  there is shown an alternative embodiment  80  of the device of the present invention, wherein the dilatation component comprises a self expandable stent  72 . 
         [0152]    Referring now to  FIG. 23  there is shown device  80  prior to deployment, wherein stent  72  and filter  42  are in the collapsed configuration within vessel  52 , adjacent to plaque  54 . Device  80  is provided with protective sheath  74  which retains stent  72  in a collapsed configuration, having a narrow profile, and which is gradually pulled back from stent  72  during deployment, enabling expansion of stent  72 . 
         [0153]    Referring now to  FIG. 24  there is shown device  80  partially deployed, wherein upon removal of protective sheath  74  from a portion of stent  72 , by gently pulling towards proximal end of stent  72 , the portion of stent  72  which is released from sheath  74  expands to its full diameter, thereby pressing against plaque  54 . Filter  42  is opened prior to full deployment of stent  72  to enable trapping of any emboli released from plaque  54  during deployment of stent  72 . 
         [0154]    Referring now to  FIG. 25  there is shown a device  80  wherein protective sheath  74  is totally removed beyond distal end of stent  72 , such that stent  72  is fully deployed, crushing plaque  54 . Emboli  56  released from plaque  54  are trapped within filter  42 . 
         [0155]    As shown in  FIG. 26 , following deployment of stent  72  and release of emboli  56  from crushed plaque  54 , filter  42  is collapsed, such that emboli  56  are trapped within filter  42  prior to removal of device  80  from blood vessel  52 . 
         [0156]    Referring now to  FIGS. 27-28  there is shown the embolization protection device  100  according to the Trans Apical approach to valve implantation, according to a preferred embodiment of the present invention. The inventive device  100  comprises a guide wire  138 , dilatation balloon  134 , retraction filament  144 , flexible filter  142 , device delivery catheter shaft  132  and an aortic valve carrying stent  150 . 
         [0157]    The valve carrying stent  150  is not limited to only an aortic valve, but may also be a pulmonic or tri-cuspid valve-carrying stent. 
         [0158]    Filter  142  may optionally comprise either a shape memory metal, comprising an alloy such as copper-zinc-aluminum-nickel, copper-aluminum-nickel, or nickel-titanium, (for example, Nitinol), or a mesh of very thin polymeric material (for example, ultra high molecular weight polyethylene). The pores of the filter should be of sufficient size to allow free passage of blood cells, while trapping atherosclerotic debris and thrombi emboli. Preferably, the pores are in the range of 30 to 50 microns. 
         [0159]    Filter deployment ring  140 , which controls deployment and collapsing of filter  142 , is disposed around the proximal opening of filter  142 , and comprises a shape memory metal such as Nitinol or the like. When retraction filament  144  is pulled so as to tighten filter deployment ring  140 , filter  142  is retained in a collapsed form. 
         [0160]    When retraction filament  144  is released, filter deployment ring  140  returns to its original size and shape, thereby releasing pressure on filter  142 , which is allowed to return to its original conical shape. 
         [0161]    When the filter  142  is made entirely of Nitinol or any other memory-metal, the opening and closing of the filter  142  may be controlled without deployment ring  140 . However, when filter  142  is made of very thin polymeric material, then the ring  140  should be present for the opening and closing of filter  142 . 
         [0162]    Dilatation balloon  134  is mounted on catheter shaft  132 , which extends beyond distal end  135  of balloon  134 . The diameter of shaft  132  is selected to enable deployment of shaft  132  within an artery and a left ventricle apex. For example, the diameter of a shaft for deployment within a coronary artery is approximately 1 millimeter, or less. 
         [0163]    The device  100  works in a similar way to device  30  as described in  FIGS. 2A-8 . In the case of device  100 , first a small incision is performed at the heart apex. Through this puncture catheter shaft  132  carrying the valve  150  is advanced anterogradlly. Retraction filament  144  is then released by the operator to release filter deployment ring  140  thus deploying filter  142 . Once filter  142  is deployed it is safe to inflate balloon  134 , which is positioned at the native aortic valve annulus, so as to deploy the valve-carrying stent  150 , mounted on the middle of balloon  134 . Once valve  150  is deployed balloon  134  is deflated (not shown), thus releasing emboli fragments downstream from the valve deployment site, which become trapped in filter  142 . Filter  142  is then collapsed by pulling retraction filament  144 , and device  100  is ready to be withdrawn from the heart, leaving the valve carrying stent  150  at the valve deployment site. 
         [0164]    The size of the PAVI device  100  and TAVI device  100 ′ prior to deployment is approximately 5-8 mm, and after deployment is approximately 25-35 mm about 5-8 times larger than the Angioplasty devices  30  and  70 . 
         [0165]    Referring now to  FIG. 29  there is shown the embolization protection device  100 ′ according to the Trans Femoral approach (TAVI) to a valve implantation, according to a preferred embodiment of the present invention. Device  100 ′ is similar to device  100  except for the filter  142 ′ being positioned before the valve-carrying stent  150 ′, unlike device  100  where the filter  142  is positioned after the valve-carrying stent  150 . 
         [0166]    In the Trans Femoral (TAVI) approach, catheter shaft  132 ′ carrying aortic valve  150  is advanced retrogradlly into the aorta, and artificial valve  150 ′ is positioned at the native aortic valve annulus. Because the blood flows from valve  150 ′ towards filter  142 ′, filter  142 ′ must be downstream to valve  150 ′. This way, filter  142 ′ is opened in the direction opposite that of filter  142  of device  100 . In order to control the opening and closing of filter  142 ′ by the operator, retraction filament  144 ′ exits catheter shaft  132 ′ proximal to balloon  134 ′ and distal to filter  142 ′, and there it is diverted  180 ° towards the opposite direction, towards filter  142 ′, by a stationary or pivotable point designated as retraction filament reversing-point  146 , and filament  144 ′ is wrapped around filter  142 ′, forming filter deployment ring  140 ′. This design allows the operator to control the deployment of filter  142 ′ by pulling filament  144 ′, and to close filter  142 ′ by releasing filament  144 ′. 
         [0167]    The valve carrying stent  150 ′ is not limited to only an aortic valve, but may also be a pulmonic or tri-cuspid valve-carrying stent. 
         [0168]    Referring now to  FIGS. 30-31  there is shown the mode of action of device  100 ′ which is similar to that of device  100 . 
         [0169]    In  FIG. 30 , device  100 ′ is advanced to the native aortic valve annulus, there filter  142 ′ is deployed by the release of retraction filament  144 ′, then balloon  134 ′ is inflated to deploy valve-carrying stent  150 ′. 
         [0170]    As shown in  FIG. 31 , balloon  134 ′ is then deflated, releasing emboli trapped by filter  142 ′, and filter  142 ′ is then closed by pulling filament  144 ′ and device  100 ′ is then withdrawn from the heart, leaving behind valve carrying stent  150 ′ at the deployment site. 
         [0171]    The inventive distal embolization protection component, according to the preferred embodiments of the present invention, can be used for any stent over balloon deployment system, or self-expandable stent, known in the art, as well as any endoluminal method that involves balloon inflation inside any blood vessel like coronary, intra-cerebral arteries, carotid, renal and alike. 
         [0172]    Although particular embodiments of the invention have been described and illustrated herein, it is recognized that modifications and variations may readily occur to those skilled in the art and consequently, it is intended that the claims be interpreted to cover such modifications and equivalents.