US 20080147114 A1
A device for sealing a hole in a blood vessel, comprising:
1. A method of providing a tool in a blood vessel of a patient, comprising:
accessing the blood vessel via an accessing pathway;
mounting an apertured element to the blood vessel;
using said apertured element to access said blood vessel;
sealing said apertured element, such that substantially no blood flows through said apertured element; and
leaving said sealed apertured element mounted on said blood vessel after closing said accessing pathway.
The application is a continuation of pending U.S. patent application Ser. No. 09/701,523, filed on Nov. 28, 2000, which is a National Phase of PCT Patent Application PCT/IL99/00285 having International Filing Date of May 30, 1999 which claims the benefit of Israel Patent Application Nos. 129067 filed on Mar. 19, 1999 and No. 124694 filed on May 29, 1998. The contents of the above applications are incorporated herein by reference.
The present invention relates to vascular devices and especially to sealing vascular devices.
There are many medical procedures in which a tube is temporarily inserted into—or out of—a blood vessel. One particular example is the use of a heart-lung machine during heart surgery. A first cannula is inserted into the aorta to return blood after it was oxygenated by the heart-lung machine. One or more second cannulas are inserted into the vena cava or the right atria. When the heart surgery is completed, the two cannulas are removed and the holes in the vena cava and aorta are closed using a “purse-string” suture, in which a single thread is stitched to surround the hole and then pulled tight (like a purse-string) to close the hole. Performing this suture requires skill and practice. In addition, it may be difficult to perform the suturing in a key-hole procedure or in other types of surgery where there is limited access to the wound site. Typically, the suture is attached as soon as the cannula is inserted into the body.
Another type of temporary tube insertion occurs during a failed anastomosis procedure. If the joining of two blood vessels fails, the point at which an opening (if any) was formed in one of the blood vessels, must be sutured shut, also possibly using a purse string.
Vascular ports, for example for the introduction of a catheter into a femoral artery, are known. Once the procedure is completed, the port is usually removed and the hole formed by the port is either sutured or closed using manual pressure. These ports are generally applied through the skin or a small incision and remain mostly outside the body.
An aspect of some preferred embodiments of the invention relates to a self-sealing anastomotic device. In a preferred embodiment of the invention, if an anastomosis cannot or is not completed, the device seals any opening in the vessel to which the device is connected. In a preferred embodiment of the invention, the device seals the opening by forcing the lips of the opening against each other or against a part of the device. Alternatively, the device seals the opening by forcing portions of the device against each other. In some embodiments of the invention, the anastomosis device severs a portion of one of the vessels of the anastomosis, for example an “end” vessel in an end-to-side anastomosis. Alternatively or additionally, the device, when it seals the opening, engages a larger portion of the blood vessel to which it is attached, to form a seal.
Alternatively to an integral device, the opening sealer may for an element which is brought over an existing anastomosis device or blood vessel, to seal the opening in the device or the blood vessel. In one example, the element comprises a collapsing ring which compresses the diameter of an anastomosis device and/or a blood vessel. Possibly, the element also severs a portion of the blood vessel, leaving only a stub, which stub is sealed. In some embodiments a double seal is formed, one at the severing location and one nearer to the blood.
In a preferred embodiment of the invention, a three configuration anastomosis device is provided. In a first configuration, the device is not deployed. In a second configuration, the device engages only one blood vessel. In a third configuration, the device either engages a second blood vessel or is sealed, depending on whether a second blood vessel is available and/or whether there is a tube or other spacer inserted in (or outside) the device when the device is changed from the second configuration to the third configuration. Alternatively, separate third and fourth configurations are provided. In the third configuration an anastomosis is performed in the fourth configuration the device is sealed. Preferably, the configuration to be used can be selected during the use of the device.
An aspect of some preferred embodiments of the invention relates to a self-sealing vascular port, at least a portion of which remains in the body after the usage of the port is completed to seal a hole in the vessel in which the port was inserted. In a preferred embodiment of the invention, the hole is sealed by portions of the device which are urged against each other. Alternatively, the hole is sealed by the device urging portions of the vessel against each other and/or against the device.
In a preferred embodiment of the invention, the port comprises a single element having both a sleeve function, to guide the insertion of objects into the port and a closure function to seal the hole when the port has completed its task. A valve function, for selectively allowing entry into the blood vessel may be integrated with the closure function or with the sleeve function, or may be a separate function. In some preferred embodiments of the invention, the valve can be opened by a tube pressing against it from outside the blood vessel or from inside the blood vessel.
Alternatively, the port comprises at least two portions, a removable sleeve portion and a closure portion which remains adjacent the blood vessel after the sleeve is removed.
An aspect of some preferred embodiments of the invention relates to a self-tightening purse-string attachment. In a preferred embodiment of the invention, the attachment is connected to one or more sutures which take part in a purse-string suture arrangement for closing a hole. When a tube inside the hole is removed, the attachment retracts the sutures, pulling the purse-string arrangement shut and thereby sealing the hole.
There is thus provided in accordance with a preferred embodiment of the invention, a device for sealing a hole in a blood vessel, comprising:
a blood vessel engager comprising at least one spike, for engaging a portion of a blood vessel adjacent a hole in the blood vessel; and
a body coupled to the blood vessel engager,
wherein said device has at least two configurations, a first configuration in which said device does not seal the hole and a second configuration to which said device can be changed, in which second configuration said device seals said hole. Preferably, said body defines a lumen therethrough. Preferably, said device comprises a second blood vessel engager for engaging a second blood vessel, such that the device can perform an anastomosis between said blood vessel and said second blood vessel.
Alternatively, said lumen is adapted to receive a tube therein, which lumen closes around said tube. Preferably, said body includes a valve for performing said closing. Alternatively or additionally, said body is radially compressed to perform said closing. Alternatively or additionally, said lumen is adapted for multiple insertions and removals of said tube. Alternatively or additionally, said lumen self-seals after said tube is removed.
In a preferred embodiment of the invention, said device is arranged to change configuration with less applied force, after said tube is removed.
In a preferred embodiment of the invention, said device is arranged to form said hole in said vessel. Alternatively or additionally, said at least one spike is arranged to engage said vessel after said hole has a final diameter, which final diameter is a diameter at which one or more tubes will be passed through said hole. Alternatively, said at least one spike is arranged to engage said vessel before said hole has a final diameter, which final diameter is a diameter at which one or more tubes will be passed through said hole. Alternatively, said at least one spike is arranged to engage said vessel before said hole is formed.
In a preferred embodiment of the invention, said at least one spike distorts when changing between said configurations. Alternatively or additionally, said configuration change comprises a distortion of said body. Alternatively or additionally, said at least one spike does not distort when changing between said configurations.
In a preferred embodiment of the invention, said body comprises a ring. Alternatively, said body comprises a hollow cylinder.
In a preferred embodiment of the invention, said configuration change comprises plastic distortion of at least part of the device. Alternatively or additionally, said configuration change comprises elastic distortion of at least part of the device. Alternatively or additionally, said configuration change comprises super-elastic distortion of at least part of the device. Alternatively or additionally, said configuration change comprises temperature-triggered shape-memory distortion of at least part of the device. Alternatively or additionally, in said second configuration, said at least one spike urges a first portion of said blood vessel against a second portion of said blood vessel, to seal said hole. Preferably, said device is arranged so that intimas of said two blood vessels are urged against each other to form said seal, by said configuration change.
In a preferred embodiment of the invention, said device is arranged so that in said second configuration, said at least one spike urges a first portion of said blood vessel against a portion of said device, to seal said hole. Alternatively, said device is arranged so that in said second configuration, a first portion of said device is urged against a second portion of said device, to seal said hole.
In a preferred embodiment of the invention, said device is adapted to be attached to a side of a blood vessel. Alternatively or additionally, said device is adapted to be attached to an end of a blood vessel.
In a preferred embodiment of the invention, said device is adapted to seal said hole and to remain in a body after a wound for accessing said device is closed. Preferably, said device remains at least two weeks in said body after said wound is healed. Alternatively or additionally, said body comprises a detachable portion which portion is removed prior to closing said wound.
In a preferred embodiment of the invention, said configuration change comprises a star distortion in which a circular profile of said body changes to a star profile. Alternatively or additionally, said configuration change comprises a rotational distortion in which a donut shaped body distorts around its median axis.
In a preferred embodiment of the invention, said seal comprises a single seal. Alternatively, said seal comprises a double seal.
There is also provided in accordance with a preferred embodiment of the invention, a method of providing a tool in a blood vessel of a patient, comprising:
attaching a port to the blood vessel;
using said port to access said blood vessel;
sealing said port; and
leaving said sealed port attached to said blood vessel for at least two weeks, wherein said port is completely enclosed by flesh of the patient. Preferably, removing a tube from said port causes said port to seal.
The invention will be more clearly understood by reference to the following description of preferred embodiments thereof in conjunction with the figures, wherein identical structures, elements or parts which appear in more than one figure are labeled with the same numeral in all the figures in which they appear, in which:
Various mechanisms may be utilized to cause the change in configuration of port 100, including passive mechanisms, in which the port changes configuration by itself, active mechanisms in which the force is applied to the port and triggered mechanisms, in which a trigger is released by some means and the port then passively (or as a result of an outside force) distorts.
Passive mechanisms include for example, elasticity, super-elasticity and shape memory mechanisms. In one example, port 100 is pre-stressed to desire to achieve the configuration of
Active mechanisms include, for example, applying force to distort port 100. In one example, the force is applied by tube 108 during its removal. During which removal, the tube, if it engages the port, can, for example, plastically distort the port. In another example, the force is applied using a second device, for example a surrounding balloon (shown in
Triggered mechanisms, include, for example a pin, which restrains the port from sealing. When the pin is removed, the port passively (or actively) distorts and seals (shown in
As can be appreciated, various types of distortions of port 100 may be utilized, including the following (and combinations of the following) types of distortion:
(a) symmetric distortions, in which a similar distortion is applied to several parts of the port, for example a rotation around ring 110, an example of which is shown in
(b) asymmetric distortion, for example squeezing the port from a circular shape to an elliptical shape;
(c) rotational distortion, for example median-axis distortion as shown in
(d) iris-type distortion, in which the port, or at least parts of it collapse inwards like an iris;
(e) partial distortion, in which part of port 100 distorts and part remains stable, for example when the spikes are not distorted but their base is, or vice versa;
(f) various types of distortion of outlines, for example from an arc to a sine wave (
(g) spiral distortion, for example in
(h) varying amounts distortion, like a star distortion shown in
The embodiment of
Port 100, as described above can be designed to have only one set of spikes 104. When the port is distorted, all of the spikes move, as a group, to seal the port.
In a preferred embodiment of the invention, once the utilization of port 100 is completed, port 100 is sealed. In a preferred embodiment of the invention, port 100 remains in the body. In some cases, it may be desirable to remove port 100, however, this is generally not required.
It should be noted that although the ring (or its replacement-variations) are shown as having a cross-section which is substantially perpendicular to the blood vessel surface, the ring-cross-section can be at other angles to the vessel, for example parallel to the vessel surface. Further, this angle can vary along the device or as a function of the deployment configuration of the device.
In a preferred embodiment of the invention, port 100 includes a layer of clot inducing material outside the blood vessel, to induce clotting in any blood which escapes the seal. Such a layer may be provided as a coating on port 100. Alternatively or additionally, such a layer is provided during or after the deployment of port 100. Alternatively or additionally, port 100 includes an adhesive layer, to glue the lips of the port to each other and/or to the lips of vessel 102 at the hole that the port creates.
As illustrated in
The lips of the port may be formed of a continuous ring. In some embodiments, the lips are formed of a plurality of overlapping or non-overlapping leaflets. The overlapping may be at the sides of the leaflets and/or at the tips of the leaflets. In some preferred embodiments of the invention, a leaflet includes one or more crevices and/or protrusions to engage other leaflets and aid in forming the seal.
In a preferred embodiment of the invention, the port is formed of hard material, such as a metal, for example stainless steel or an NiTi alloy or a plastic. Alternatively or additionally, the port is formed of a soft material, such as a silicon rubber. In various preferred embodiments of the invention, the port, or parts thereof, exhibit elastic, super elastic, plastic and/or shape memory properties. In some preferred embodiments of the invention, the port is formed of a rigid frame which is coated with a soft layer, such as silicon rubber. The frame preferably provides the ability for the port to passively or actively distort and the silicon preferably provides a resilient seal and/or a pressure distributing means.
In some preferred embodiments of the invention, the port is formed of bio-absorbable materials, preferably, so that after a time the port dissolves or is otherwise broken down, completely, or at least in part.
A PCT application titled “Methods and Devices for Vascular Surgery”, filed on even date with the instant application in the Israel receiving office of the PCT and having same applicants, the disclosure of which are incorporated herein by reference, describes various anastomotic connectors. Some of these anastomotic connectors include a mechanism for engaging a blood vessel, entering (or exiting) the blood vessel, and/or maintaining a hole in a blood vessel. In a preferred embodiment of the invention, these mechanisms are utilized for providing and/or using a self-sealing port, as described herein.
One or more of the following issues are preferably taken into account when designing and/or selecting a device for sealing a port. These issues are listed in a general order corresponding to the steps of using such a device.
A first issue is bringing the port to the blood vessel. In a preferred embodiment of the invention, a port is brought to a blood vessel using a catheter (inside the blood vessel) or an endoscope (from outside the blood vessel). In some cases, the port is used in a surgical procedure in which the access to the blood vessel is a keyhole surgical wound or a standard surgical wound. Preferably, the port is formed of an elastic material so that it can be radially and/or axially compressed during the provision of the port.
A second issue is engaging the blood vessel by the port. In a preferred embodiment of the invention, the port includes spikes which, can be selectively bent (or released) when the port is brought into contact with the blood vessel, thereby engaging the vessel. Alternatively or additionally, the port may be sutured to the vessel, preferably using a minimally invasive technique, for example as described in PCT publication WO 98/42262, the disclosure of which is incorporated herein by reference. Alternatively or additionally, the engaging is integrated with the hole making, described below. In a preferred embodiment of the invention, the port is provided in a first undistorted configuration. When the port is placed against the vessel, the port (or part of it) is distorted, thereby allowing the spikes to engage the vessel. Sealing the port is preferably achieved by further distorting the port. Alternatively, in some configurations, if the port is distorted using a force opposite to the one which caused the distortion in the first place, the port seals, rather than being removed (for example utilizing a structure such as in the embodiments of
Engaging the blood vessel may be achieved by various mechanisms for folding, extending and bending spikes while deploying an implantable device. As described in the above PCT application of even date, spikes can be bent using many mechanisms, including elasticity, cantilevering, twisting and bending by force.
A third issue is forming the hole in vessel 102. In a preferred embodiment of the invention, the hole is formed using a sharp tip or a knife, possibly provided using the same means as the port, and/or provided through the opening in the port. Alternatively, the port itself, for example in a first, distorted configuration, has a sharp tip which forms the hole. For example, in the embodiment of
A fourth issue is expanding a hole in vessel 102 to the desired size of the port. In some cases, the hole is formed at its full size. However, in other cases, the formed hole is small and needs to be expanded. In a preferred embodiment of the invention, the hole is expanded using a balloon which is inflated in the hole. Alternatively or additionally, the hole is expanded by causing spikes 104 which engages vessel 102 to travel away from each other, thereby expanding the hole. It should be appreciated that the engagement of vessel 102 may possibly proceed in several steps or may occur only after the hole is formed. In one example, spikes 104 engage vessel 102 only after the hole is formed and then expanded using a balloon. A different set of spikes (if any) may be used for the primary engagement of the vessel, in which engagement the port is coupled to the vessel.
A fifth issue is maintaining the hole in vessel 102. In some cases, for example in some types of passive ports, the port, if left alone, seals the port. The hole is preferably maintained by restraining the port from closing, for example by inserting tube 108 therethrough. Alternatively, the port comprises a bi-stable configuration, with the stable states being “open” and “closed”. A bi-stable element is described in PCT publication WO 98/32412, the disclosure of which is incorporated herein by reference. In this PCT publication, a stent with two stable radii is described. A similar configuration as the stent, but including spikes at one end thereof (as in
In the bi-stable embodiment of present invention, once the port is in the open state, it will tend to stay open, unless the port is shifted to the closed state. Alternatively to a bi-stable mechanism, a ratchet based mechanism may be used, either to create a “normally open” port or a “normally closed” port. Once the port is in one state, the ratchet latches and the port can change configuration only by application of a large force or by releasing the latch (for example a pin as described in
A sixth issue is distorting the port or parts thereof. The above PCT application of even date describes various mechanisms of distorting an implant, including shape-memory, balloons, including balloons or other distorting tools, possibly with fingers for pressing against particular points on the port structure, and bi-stable structures. Any of these mechanisms may be applied towards constructing a port in accordance with a preferred embodiment of the invention. It should be appreciated that different parts of the port, for example the ring and the spikes, or individual spikes, may be distorted in different ways and by different amounts. Further, a same part of the port may be distortable in more than one way.
A seventh issue is how much of the port remains in contact with the blood flow after the port is sealed. As can be seen in various embodiments described herein, the contact area can be large, for example the entire size of the hole. Alternatively it can be small, for example is the hole is shrunken by the closure of the port. It can be minuscule, for example if only small portions of the spikes remain in the blood stream or no contact can remain, for example if the spikes do not penetrate to the inside of vessel 102 or if the portion which is penetrated is outside the seal. By suitable distortion of the port, a port may be applied from inside a blood vessel and then seal such that most or all of the port is outside the blood vessel.
An eighth issue is the amount of eversion caused by the port. Two measures of eversion can be recognized, the angle between the everted portion and the rest of the vessel and the length of vessel which is everted out of the plane of the vessel surface. In various embodiments described herein, different degrees of both measures may be achieved. In some cases, for example in Aortic hole-closing, it may be desirable to minimize both measures of eversion.
A ninth issue is the profile of the closed hole. The profile depends both on the eversion and on the shape of the port when it is sealed. In some applications, it is desirable that the port be as flush as possible with the vessel surface, lack and sharp edges and/or have a minimum effect on the inner lumen of the blood vessel. In other applications some or all of these features are not required. In some embodiments described herein, the port may be axially compressed or its protruding lips cut off or folded down, to minimize the protrusion of the device from the vessel surface. This further distortions may be passive, active, triggered by the collapsing of the device, and/or meditated by a time delay, such as by the dissolution of bio-absorbable pins holding the port together.
A tenth issue relates to the relative distortion and/or motion of the spikes as compared to the body of the device. In some embodiments, the spikes move independently of the ring, for example bending and/or unfolding. In other embodiments, it is the ring that distorts with a possible result of movement of the spikes. In other embodiments, various combinations of the rings distorting and the spikes distorting may be employed.
The above devices have been described mainly as temporary ports. However, it is noted that when an anastomosis is made, and fails to be completed, the effect is similar to that of a port. In a preferred embodiment of the invention, an anastomosis device is provided that self-seals if the anastomosis is not completed. Various embodiments of anastomosis devices are described in the above referenced PCT application of even date.
If an anastomosis in not desired, for example if vessel 374 fails at its other end, vessel 374 is not provided and neither is catheter 372 (at least not to proximal portion 364). Pivot 368 preferably comprises a ring which is restrained from having its radius change. Thus, when the radius of portion 366 is increased, pivot 368 transfers the force to portion 364, whose radius decreases, causing the port to seal, for example by the spike moving towards each other. Preferably, the materiel characteristics of pivot 368, distal portion 366 and proximal portion 364 are selected so that pivot 368 (and not portion 366) will plastically distort under the force of the expansion of portion 366. However, pivot 368 is preferably strong enough to resist plastic deformation at a force which is strong enough to distort the most proximal section of proximal portion 364, so that moving of the spikes is a preferred occurrence to plastic distortion at the pivot.
As shown in
The embodiment of
With reference to portion 219 it is noted that portion 219 can serve as a pivot (as in
In some embodiments of the invention, portion 219 (or pivot 368 of
Alternatively or additionally, sealer 210 utilizes a double action mechanism. The sealer is provided at a diameter similar to that of catheter 216. A first activation of the sealer causes spikes 214 to extend outwards, as shown in
When holder 358 is retracted, ring 352 distorts (preferably elastically, super elastically or based on a shape memory) around its median axis, as shown in
In a preferred embodiment of the invention, device 350 acts as a fail safe for vascular surgery. If holder 358 is disturbed or otherwise slips off of protrusions 356, the device seals the hole in the blood vessel. the hole can be reopened using a suitable tool which distorts the configuration of
In a preferred embodiment of the invention, a port device is attached to a blood vessel from inside the blood vessel. For example, if device 350 is super-elastic, it can be radially compressed so that it can be provided through the hole, while maintaining it in the configuration of
The above description has focused on temporary ports and anastomosis devices. However, it should be noted that the same or similar devices can be used for sealing holes and/or making other repairs in blood vessels. Such a sealer can be provided over a catheter which is inserted into a hole. The catheter preferably comprises inflatable cuffs which can be used to block blood flow from the damaged area while the sealing is being performed.
Additionally, the above devices can be used for inserting a small diameter wire or tube into and/or out of a blood vessel. Typically, a relatively large diameter catheter is required for guiding the wire to its destination. In some cases, the wire may have a larger tip, for example a sensor or a pacing electrode. In a preferred embodiment of the invention, the wire and catheter are provided through a port as described herein. When the catheter is retracted the port is sealed, on the wire. Preferably, the seal is also utilized to stabilize the position and/or rotation of the wire.
A different use for passing a wire through a seal of the port is to ease the reopening of the port. As indicated above, some types of ports can be opened after they are sealed. In a preferred embodiment of the invention, the wire is coupled to the port. When it is desired to open the port, a catheter is guided over the wire to the port. Preferably, a greater contra-force on the port can be generated by pulling on the wire while advancing the catheter. Thus, there is also less danger of applying force against a part of vessel 102 opposite the port. If the wire passes through the seal, in a preferred embodiment of the invention, the catheter is advanced along the wire until it passes through the port. Alternatively or additionally, pulling on the wire distorts the port so that it opens, is easier to open or is able to be opened, from the force of the catheter against it. In some embodiments, the wire is attached to the portion of the port which is outside the blood vessel.
It should be appreciated that many of the structures described herein may also be applied to other invasive and/or implantable devices, beyond those used for anastomosis, especially such devices which are inflatable, expandable and/or otherwise deployed. However, as will be appreciated, that some of the above described structures solve particular problems of port sealing, for example functioning as a port and sealing a hole in a blood vessel.
It will be appreciated that the above described methods of applying a vascular port and sealing a hole may be varied in many ways, including, changing the order of steps and the methods of distortion used. In addition, a multiplicity of various features, both of method and of devices have been described. It should be appreciated that different features may be combined in different ways. In particular, not all the features shown above in a particular embodiment are necessary in every similar preferred embodiment of the invention. Further, combinations of the above features are also considered to be within the scope of some preferred embodiments of the invention. Also within the scope of the invention are surgical kits which include sets of medical devices suitable for making a single or a small number of ports or sealing holes of various sizes. When used in the following claims, the terms “comprises”, “includes”, “have” and their conjugates mean “including but not limited to”.
It will be appreciated by a person skilled in the art that the present invention is not limited by what has thus far been described. Rather, the scope of the present invention is limited only by the following claims.