Device for establishing supplemental circulatory blood flow

(Cross reference) This application is a partial continuation of PCT application No. PCT / US07 / 76965 (pending) filed on August 28, 2007, the entire disclosure of which is expressly incorporated herein by reference. Claims priority to US Provisional Patent Application No. 60 / 823,971 (pending) entitled "Devices, Methods and Systems for Establishing Supplemental Blood Flow in the Circulatory System" filed on August 30, 2006. It is a thing. This application is generally pending at the same date, entitled "Cannula Insertion Devices, Systems, And Methods Including A Compressible Member," which is expressly incorporated herein by reference in its entirety. It also relates to US Patent Application No. 11 / 846,886.

The present invention generally relates to medical devices and methods, and more particularly to methods and devices for fluid coupling to a patient's heart in a system that aids the patient's blood circulation.

Various devices and methods have been used to guide blood from the heart and aid the patient's blood circulation. This is often desirable or needed if the patient has congestive heart failure and has not yet received a transplanted organ, or if the patient is not suitable for transplantation. Blood pumps are usually attached directly to the left ventricle of the heart, but in at least one blood pump system the pumps are pacemaker-style and remotely located, such as subcutaneously. In this regard, see Patent Document 1, whose disclosure is fully incorporated herein by reference. In this or similar situation, a cannula can be used to create an inflow duct from the heart (intrathoracic site) to a superficial (non-thoracic) pump called a "pacemaker pocket." Of course, other distant sites are also possible alternatives. Pacemaker pockets are sites that are usually accessed by a surgical incision under the clavicle that extends downward toward the breast and over the pectoralis major, approximately parallel to the clavicle. Pacemaker pockets are sometimes created under the muscles. The pump to which the cannula is connected sits in the chest pocket, preferably, but not exclusively, in the area on the right side of the chest.

The part that needs improvement is the insertion device or trocar used to send the inflow conduit or cannula to the heart. Improves surgeon control of the position of the tip of the insertion device to minimize damage to the heart tissue in the process of inserting the tip of the insertion device into the cardiac cavity through an incision or other opening in the heart tissue. It is desirable to provide an insertion device configured to facilitate this procedure and reduce surgical time. It is also desirable to provide an insertion device that can be tightly engaged with and disengaged from the inflow cannula while the cannula is being inserted into the heart chamber.

Well-known, general cannula transplantation methods that can be used in connection with the present invention include various methods, some of which are described further below. For example, it can be transplanted by inserting the cannula directly into the thoracic cavity. Surgical methods include so-called open heart surgery, in which a median sternotomy is performed to completely expose the heart within the thoracic cavity. Other surgical methods include minimally invasive surgical methods such as thoracotomy, small thoracotomy, video-assisted thoracoscopic surgery, or any other minimally invasive procedure. As described herein, the other surgical methods described above can be used to implant the cannula into fluid communication with any desired site of the heart.

<p><patcit num="1"><text>U.S. Pat. No. 6,530,876</text></patcit><patcit num="2"><text>U.S. Pat. No. 6,176,848</text></patcit><patcit num="3"><text>U.S. Pat. No. 6,116,862</text></patcit><patcit num="4"><text>U.S. Pat. No. 6,942,611</text></patcit><patcit num="5"><text>U.S. Pat. No. 6,623,475</text></patcit><patcit num="6"><text>German Patent No. DE 10 2004 019 721.0</text></patcit></p>

<p> An object of the present invention is to provide a method and a device for fluid coupling to a patient's heart with a system that assists the patient's blood circulation.</p>

<p> Overall, and in one of many embodiments, the present invention establishes a blood flow conduit between the patient's heart chamber and a remote site, such as a site away from the heart where the blood pump is located. Provides devices for. In this regard, as used herein, the term "away" refers to a distance from the heart, but is not limited to a particular distance from the heart. The devices and systems of the present invention include an inflow cannula having a lumen and an insertion device that is received within the lumen of the inflow cannula and is configured to facilitate insertion of a portion of the inflow cannula into the heart chamber. The insertion device comprises a distal end portion (for the surgeon implanting the cannula), a proximal end portion, and a shaft having multiple lumens formed within the shaft. The first of the cavities is configured to receive the guide wire in it, and the second of the cavities is configured to receive the pressurized fluid in it. The insertion device further includes a tip that is connected to the distal end portion of the shaft and is configured to be inserted into the heart chamber. The tip has a hollow interior that communicates with the first of the shaft's cavities. The insertion device also includes an inflatable member, which is coupled to the distal end portion of the shaft and has a hollow interior that is in fluid communication with a second of the shaft's cavities. The inflatable member is movable between a first contracted configuration and a second inflated configuration that releasably secures the insertion device to the inflow cannula.</p><p> In other embodiments, the system can include one or more of the following features: The system can further include a blood pump with inlets and outlets, an outflow cannula configured so that one end is coupled to the outlet of the pump and the opposite end is coupled to the patient's arterial system. The proximal end of the inflow cannula can be coupled to the inlet of the blood pump and the distal end of the inflow cannula is configured to be inserted into the heart chamber.</p><p> The insertion device can further include a hub attached to the proximal end portion of the shaft. The hub is formed in a first leg having a first lumen formed in a first leg communicating with the first one in the shaft lumen, and in a second leg, the shaft lumen. A second leg with a second lumen in fluid communication with the second one can be included. The second leg can be configured to be coupled to the fluid source. The shaft can further include an aperture formed in the second of the shaft's lumen and in the hollow interior of the inflatable member and at the distal end of the fluid communication state. The inflatable member becomes a generally cylindrical sleeve when inflated. In one embodiment, the shaft can include three cavities, one of which is configured to receive a guidewire in it and the other two are fluid communication with the hollow interior of an inflatable member. It is in a state. The shaft may include inner and outer cylindrical protrusions connected by ribs spaced apart from each other in the circumferential direction.</p><p> In another aspect, the invention provides a system for inserting a cannula through living tissue. The system includes a cannula having a lumen and an insertion device that is received within the lumen of the cannula and is configured to facilitate the insertion of a portion of the cannula through living tissue. The insertion device includes a shaft having a proximal end portion and a distal end portion, and a tip connected to the distal end portion of the shaft. The tip is configured to be inserted through living tissue. The system also includes an expandable member coupled to the distal end of the shaft, which includes a first configuration in which the expandable member is disengaged from the inflow cannula and an expandable member. It is movable between a second configuration that is releasably fixed to the inflow cannula.</p><p> In another aspect, the invention provides a method of inserting an inflow cannula with a lumen into the heart chamber of a patient. The method comprises inserting the insertion device into the lumen of the inflow cannula and at least a portion of the tip of the insertion device projecting beyond the distal end portion of the inflow cannula. The insertion device further includes a shaft, the tip of which is secured to the distal end of the shaft, and an expandable member is coupled to the distal end of the shaft. The method further comprises expanding the expandable member to releasably secure the inflow cannula to the insertion device and inserting the tip of the insertion device and the distal end portion of the inflow cannula into the heart chamber.</p><p> In other embodiments, the method of inserting the influx cannula into the patient's heart chamber can include one or more of the following steps: The expandable member may be an expandable member, and the expansion step may include a step of expanding the expandable member. This step can include directing the pressurized fluid into the hollow interior of the inflatable member through a cavity formed within the shaft of the insertion device. A puncture site can be created in the tissue defining the cavity and the puncture site can be gradually enlarged at the tip of the insertion device to a larger size to facilitate insertion of the distal end of the inflow cannula into the heart chamber. it can. After anchoring the inflow cannula to the heart tissue that demarcates the cavity and fixing the cannula to the heart tissue, the expandable member can be disengaged from the cannula.</p><p> In another aspect, the invention provides a method of inserting a cannula having a lumen through a living tissue. The method comprises inserting the insertion device into the lumen of the cannula and at least a portion of the tip of the insertion device projecting beyond the distal end portion of the cannula. The insertion device further includes a shaft, the tip of which is secured to the distal end portion of the shaft, and an expandable member is coupled to the distal end portion of the shaft. The method further comprises expanding the expandable member to releasably secure the cannula to the insertion device and inserting the tip of the insertion device and the distal end portion of the cannula through the tissue.</p><p> Examination of the following detailed description of the exemplary embodiments in conjunction with the accompanying drawings will further facilitate the understanding of various other features and embodiments.</p>

<figref num="1">FIG. 6 is a schematic representation of the anatomical structure of the chest showing an example of a pathway outside the venous system used for access to the patient's heart and transplantation of a circulatory assist system according to an embodiment of the invention.</figref><figref num="2">An inflow cannula in which the insertion device according to an embodiment of the present invention extends through the lumen of the inflow cannula and the inflatable member of the insertion device is inflated to leasably secure the insertion device to the inflow cannula. It is a cross-sectional view.</figref><figref num="3A">FIG. 5 is a cross-sectional view taken along line 3A-3A of FIG. 2 in which the inflatable member of the insertion device is inflated.</figref><figref num="3B">FIG. 5 is a cross-sectional view taken along line 3B-3B of FIG. 7F with the inflatable member of the insertion device contracted.</figref><figref num="4">FIG. 5 is a cross-sectional view showing a part of the hub and shaft of the insertion device shown in FIGS. 2, 3A and 3B.</figref><figref num="5">It is sectional drawing which shows the shaft of the insertion device by another embodiment of this invention.</figref><figref num="6">It is sectional drawing which shows the shaft of the insertion device by another embodiment of this invention.</figref><figref num="7A">It is an enlarged view of the heart which shows the access site to the inside of a heart.</figref><figref num="7B">Similar to Figure 7A, but with the inflow cannula oriented towards the access site, showing the exposed access site, with the insertion device and guidewire extending beyond the distal end of the inflow cannula. It is a figure which shows the place in general.</figref><figref num="7C">With the guide wire and part of the tip of the insertion device inserted into the left atrium or left atrium of the heart and the inflatable member of the insertion device inflated, the insertion device is releasably secured to the inflow cannula. FIG. 6 is a partial cross-sectional view of the heart showing the subsequent portion of the procedure.</figref><figref num="7D">The entire tip of the insertion device and the distal end of the inflow cannula, including the distal element of the cannula, are inserted into the left atrium and the associated purse suture is loosened, showing the subsequent portion of the procedure, FIG. 7C. It is a partial cross-sectional view similar to.</figref><figref num="7E">FIG. 7D is a partial cross-sectional view similar to FIG. 7D showing the subsequent portion of the procedure with the drawstring suture tightened and the tissue contracted between the proximal and distal fixation elements of the inflow cannula.</figref><figref num="7F">FIG. 6 is a cross-sectional view similar to FIG. 7E, showing the subsequent portion of the procedure in the process of removing the insertion device and guide wire from the inflow cannula.</figref><figref num="7G">It is an enlarged view showing the heart with the insertion device and the guide wire removed and the inflow cannula fixed to the left atrium wall of the heart.</figref>

FIG. 1 shows one of many possible overall configurations of an implanted blood circulation assisting system 10 according to aspects of the invention. The devices and systems configured by the teachings herein can be implanted by any suitable surgical procedure, including, but not limited to, those generally discussed herein, and the cannula is cardiac tissue. It can be used for insertion into the heart chamber through. Devices and systems configured according to aspects of the invention can also be used to insert the cannula into other living tissues, for example by inserting into the lumen of the kidney through kidney tissue.

System 10 includes an inflow cannula 12 with a distal end portion 12a passing through the left atrium 14 of the heart 15 of patient 20. For example, it is possible to access any part of the left side of the heart (eg, left atrium and / or left ventricle) to access oxygen-rich blood. The inflow cannula 12 is attached directly to the left outer wall of the heart 15, such as the left atrium wall 14a, as shown in FIGS. 7F-7G. The influx cannula 12 can be directed to the external region of the heart by any desired surgical procedure, including one of the techniques discussed in general later. The cannula 12 includes a distal fixation element 22 and a proximal fixation element 24 having a disc-like configuration in the illustrated embodiment. However, the fixing elements 22 and 24 may have other configurations as set forth in US Patent Application No. 60 / 823,971 previously referenced. Cannula 12 can be made from a variety of implants or medical grade materials such as silicone.

The blood circulation assist system 10 also includes a blood pump 30 having an inlet 32 and an outlet 34, and an outflow cannula 36. The proximal end portion 12b of the inflow cannula 12 is coupled to the inlet 32 of the blood pump 30. Any suitable blood pump 30, including those described in Patent Document 2, Patent Document 3, Patent Document 4, and Patent Document 5, or Patent Document 6, can be used. The outflow cannula 36 is connected between the outlet 34 of the pump 30 and an artery such as the superficial axillary artery 40. Therefore, blood flow flows from the left atrium 14 in the direction of arrow 42 through the pump 30 and through the outflow cannula 36 into the patient's arterial system. The outflow cannula 36 can be connected to a superficial artery, such as the axillary artery 40, by an attachment procedure that may include appropriate surgical incisions and the use of appropriate implants (not shown) and sutures (not shown).

The inflow cannula 12 and / or the outflow cannula 36 can be connected to the pump 30 before or after transplantation of the blood pump 30. First, the inflow cannula 12 and / or the outflow cannula 36 is cut to the appropriate length with an appropriate disinfected cutting tool (not shown) and as shown in US Patent Application No. 60 / 823,971 referenced earlier. The system can be more easily implanted, for example, in the chest pacemaker pocket, without twisting the cannulas 12, 36.

The insertion device 200 according to one embodiment of the invention can be used in any suitable surgical procedure to deliver the influx cannula 12 to the heart 15. The insertion device 200 has a plurality of functions associated with the cannula, such as the inflow cannula 12. These features include: Releasably anchoring the insertion device to a cannula such as the inflow cannula 12 to improve the ability of the surgeon to deliver the cannula to the desired access site and insert the cannula through living tissue, which may be heart tissue. The hardness of the combination of the cannula and the insertion device 200 provides an expandable member that is used to minimize damage to the tissue, and gradually reduces tissue openings such as punctures or incisions. Enlarge to make the distal end of the cannula sized for easy insertion through living tissue. An example of treatment is discussed below with reference to Figures 2 and 7A-7G. FIGS. 2 and 7B-7E show the insertion device 200 inserted into the lumen 16 of the inflow cannula 12 on the guide wire 50, with the insertion device 200 being releasably secured to the inflow cannula 12.

The insertion device 200 is a shaft 206 having a distal end portion 208 (FIG. 2), a proximal end portion 210 (FIG. 4), and cavities 212, 214 (FIGS. 3A, 3B, and 4) formed therein. including. The lumen 212 is configured to receive any commercially available guide wire, such as the guide wire 50, therein. The lumen 214 is configured to receive a pressurized fluid, usually a sterile liquid, into it, for example, from a syringe, as discussed in more detail. The cavities 212 and 214 do not communicate with each other. The shaft 206 can be made from a material with a high durometer. In one embodiment, such materials can have a durometer of 63D or higher. Examples of suitable materials include, but are not limited to, thermoplastic materials such as nylon, urethane, and Pebax®. Any other suitable biocompatible material can be used to make the shaft 206.

The insertion device 200 was further coupled to a tip 220 connected to the distal end portion 208 of the shaft 206, a hub 222 connected to the proximal end portion 210 of the shaft 206, and a distal end portion 208 of the shaft 206. Includes expandable member 224. In the embodiment shown in the figure, the expandable member 224 is more specifically an expandable member. However, other insertion devices with different expandable members can be used according to aspects of the invention, as discussed in more detail later. The inflatable member 224 can at least partially expand around the distal end portion 208. The inflatable member 224 may be, for example, a balloon-like inflatable member as used in conventional balloon catheters. FIGS. 2, 3A, 7C, 7D, and 7E show an inflatable or inflatable member 224 that releasably secures the insertion device 200 to the inflow cannula 12. 3B and 7F are views showing inflatable members in which the insertion device 200 does not engage the inflow cannula 12 and is therefore not temporarily anchored to the inflow cannula 12, contracted, or folded.

The tip 220 includes a hollow interior 226 (FIG. 7C) that communicates with the lumen 212 of the shaft 206 to receive the guide wire 50. The inner diameter of the tip 220 is a size for accommodating a commercially available guide wire such as the guide wire 50, and is usually about 0.003 inch or more larger than the outer diameter of the guide wire. As discussed later with reference to FIGS. 7B-7E, the guide wire 50 projects beyond the tip 220 into the atrioventricular 14 of the heart 15 during the first phase of this procedure. The tip 220 is inserted into the atrioventricular 14 of the heart 15 and is configured to facilitate insertion of the inflow cannula 12 into the atrioventricular 14. The configuration of the tip 220 gradually enlarges the heart tissue, in this case the incision in the left atrial wall 14a, until it is large enough to receive the influx cannula 12. As shown in FIGS. 2 and 7B to 7E, this gradual expansion can be performed by a tip 220 having a stepped structure or, otherwise, by a tip having a continuous taper (not shown). it can. In each case, the tip is tapered from the proximal end to the distal end.

The tip 220 can include tapered portions 230, 232, and cylindrical portions 234, 236. The tapered portion 230, in the illustrated embodiment, is the distal end portion of the tip portion 220 and is integral with the cylindrical portion 234. The tapered portion 232 is integral with the cylindrical portion 234 and, in the embodiment shown in the figure, the cylindrical portion 236 which is the proximal end portion of the tip 220. Alternatively, the tip of the insertion device 200 can include an additional tapered portion and a cylindrical portion. Each cylindrical portion of the tip 220, in this case the cylindrical portions 234, 236, has a unique outer diameter and is from the most distal end of the cylindrical portion, in this case the cylindrical portion 234, to the cylindrical portion. The size of the outer diameter gradually increases to the most proximal end, in this case the cylindrical portion 236. For example, the cylindrical portion 234 has an outer diameter d₁The cylindrical part 236 has an outer diameter d₁Outer diameter d larger than₂Has (Fig. 7D). The number of tapers incorporated into the tip of the insertion device 200 depends on the inner diameter of the inflow cannula. In one embodiment, if the inner diameter of the inflow cannula is about 6 mm, such as the inflow cannula 12, the tip of the insertion device 200, such as the tip 220, may include two tapers. In this example, the diameter d of the cylindrical portion 234₁May be about 2 mm, diameter d of cylindrical part 236₂May be about 4 mm. But the diameter d₁And d₂Has different sizes depending on the inner diameter of the inflow cannula, such as the inflow cannula 12. For example, if the anatomical structure is not large enough to support a tip having a stepped configuration, such as the tip 220, the tip (not shown) can be provided with a continuous taper. For example, if the dimension across the heart chamber into which the tip should be inserted (from the entrance to the opposite wall) is less than the overall length of the tip with multiple tapers, then a relatively short tip with one continuous taper used.

The tip 220 can be made from a thermoplastic material such as nylon, urethane, or Pebax®, and the tip 220 can include a radiation opaque filler such as barium or tungsten. .. The filler may be a metal paste. The tip 220 can also be made from other suitable biocompatible bases and fillers. Visibility of the tip 220 when other shapes, eg, recesses (not shown) are formed in the tip 220 and transesophageal echocardiography or equivalent procedures are used during placement of the insertion device 200. The sex can be improved.

As best seen in FIG. 4, the hub 222 is configured to allow access to the cavities 212, 214 of the shaft 206. In the illustrated embodiment, the hub 222 has a leg 240 extending along the proximal end portion 210 of the shaft 206 and a lumen 242 communicating with the lumen 212 of the shaft 206. Therefore, the cavity 242 can receive the guide wire 50. The leg 240 of the hub 222 includes a luer screw 243 according to or equivalent to ISO 594, allowing the lumen 242 to be flushed before and / or after use of the insertion device 200.

Hub 222 also includes leg 244. The leg 244 can be angled with respect to the leg 240 and includes a lumen 214 of the shaft 206 and a fluid communicating lumen 246 for expanding or contracting the inflatable member 224. The shaft 206 includes at least one aperture 247 formed within the shaft 206 in close proximity to the hub 222 to establish this fluid communication. Aperture 247 may be a notch. Leg 244 is fitted to be coupled to the fluid source. The fluid is usually a liquid such as saline and can be pressurized. This can be done by providing a luer screw 248 according to or equivalent to ISO 594 for receiving the syringe 250 at the proximal end portion of the leg 244. The lumen 246 of the leg 244 of the hub 222 is in fluid communication with the hollow interior of the syringe 250 adapted to contain the fluid therein. The aperture 252 may be a notch or skive (FIGS. 3A and 3B) and is formed within a portion of the shaft 206 covered with an inflatable member 224, the cavity 214 of the shaft 206 and the hollow interior 254 of the inflatable member 224. Brings fluid communication between.

Hub 222 can be made from materials commonly used for catheter applications. Examples of suitable materials include, but are not limited to, polycarbonate and nylon. Hub 222 can also be made from other suitable biocompatible materials. The hub 222 can be fixed to the shaft 206 by adhesive or other conventional means. The hub 222 is sized to accommodate the outer diameter of a particular shaft to which the hub 222 is fixed.

As shown in FIGS. 2 and 7C-7F, the inflatable member 224 is typically located proximal to the tip 220 and can be secured to the shaft 206. The inflatable member 224 can be secured to the shaft 206 using adhesives, melting or welding treatments, or other suitable means or treatments. The inflatable member 224 takes into account the flexibility of the inflow cannula 12 and secures the inflow cannula 12 to the insertion device 200 releasably when the member 224 inflates so that the surgeon desires the inflow cannula on the heart 15. Used to help direct the access site. This imparts rigidity to at least the distal end portion 12a of the inflow cannula 12.

The inflatable member 224 becomes a generally cylindrical sleeve when inflated. Inflatation is performed by extending the plunger of the syringe 250 (not shown), thereby pressurizing the fluid in the syringe and allowing the fluid to flow through the lumen 246 of the leg 244 of the hub 222 into the lumen 214 of the shaft 206. be able to. The fluid then flows from the lumen 214 through the aperture 252 in the shaft 206 into the hollow interior 254 of the inflatable member 224, as shown by arrow 262 in FIG. 3A.

The length of the inflatable member 224, i.e. the longitudinal distance of the shaft 206, is the desired hardness of the distal end portion 12a of the inflow cannula 12, and the inflatable member 224 when the inflatable member 224 is inflated. Depends on the associated contact surface between the outer surface of the inflow cannula 12 and the inner surface of the inflow cannula 12. For example, the length of the inflatable member 224 can vary from about 5 mm to about 50 mm depending on the particular application. The outer diameter of the inflatable member 224 may be such that when the member 224 expands, a tightening allowance of about 0 to about 1 mm can be obtained from the inner surface of the inflow cannula 12.

The inflatable member 224 can be made from a thermoplastic material such as nylon, PET, polyethylene, polyurethane, or Pebax®. The inflatable member 224 can also be made from other suitable biocompatible materials. The material used to make the inflatable member 224 typically has a rated burst pressure of at least 2 atm. The wall thickness of the inflatable member 224 for a particular length of the inflatable member 224 is directly related to the desired burst pressure, material properties, and the expansion diameter of the inflatable member 224. Hooke's law can be used on thin wall cylinders to determine the wall thickness of the inflatable member 224.

The distal end portion 12a of the inflow cannula 12 is inserted at the desired location within the atrioventricular 14 and secured to the heart 15 with a drawstring suture, for example, after which the inflatable member 224 is contracted. The contraction can be performed by retracting the plunger of the syringe 250 and returning the fluid from the hollow interior 254 of the inflatable member 224 to the syringe 250. The volume of the lumen 214 in the shaft 206 is sized to allow the inflatable member 224 to be inflated and contracted within an acceptable time, for example within about 30 seconds. After the inflatable member 224 is contracted, the insertion device 200 can be withdrawn from the inflow cannula 12.

FIG. 5 shows an insertion device 200a similar to the insertion device 200, except that the insertion device 200a has a shaft 270 instead of the shaft 206 of the insertion device 200. The shaft 270 includes a cavity 271 similar to the cavity 212 of the shaft 206 for receiving the guide wire 50. Instead of a relatively large outer lumen, such as the shaft 206's lumen 214, the shaft 270 includes two relatively smaller outer lumens 272 separated by ribs 274 extending along the length of the shaft 270. Each cavity 272 is in fluid communication with the hollow interior 254 of the inflatable member 224 and the pressurized fluid source, in this case the syringe 250. The shaft 270 contains suitable apertures, which may be notches or skives (not shown) at the proximal and distal ends, and the lumen 246 and inflatable member 224 of the leg 244 of the lumen 272 and hub 222, respectively. Provides fluid communication with the hollow interior 254 of the. By incorporating the rib 274, the structural characteristics of the shaft 270 are improved.

FIG. 6 shows an insertion device 200b similar to the insertion device 200, except that the insertion device 200b has a shaft 280 instead of the shaft 206 of the insertion device 200. The shaft 280 includes an inner cylindrical protrusion 282 and an outer cylindrical protrusion 284 that are concentrically arranged and interconnected by ribs 286 that are spaced apart in a plurality of circumferential directions. Protrusions 282, 284, and ribs 286 define the lateral lumen 288. Each outer lumen 288 is in fluid communication with the hollow interior 254 of the inflatable member 224 and the pressurized fluid source, in this case the syringe 250. The shaft 280 contains suitable apertures, which may be notches or skives (not shown) at the proximal and distal ends, and the lumen 246 and inflatable member 224 of the leg 244 of the lumen 288 and hub 222, respectively. Provides fluid communication with the hollow interior 254 of the. The shaft 280 further includes an inner lumen 290 for receiving the guide wire 50.

Other alternative insertion devices (not shown) may be similar to the insertion device 200, but may further include a rigid hypotube surrounding an inner shaft containing multiple cavities made of a more flexible material, such as a thermoplastic material. it can. The hypotube may be made of metal such as stainless steel. The hypotube increases the strength of the column of the insertion device to the device, such as the insertion device 200. The alternative insertion device can further include an inner strain release and an outer strain release. An inner strain release can be added to the structure to provide a barrier between the inner shaft containing multiple cavities and the hypotube, providing a hardness change proximal to the included inflatable member. .. The inner strain release is usually a thin wall tube, which can be made from a thermoplastic material such as Pebax®, nylon, polyurethane, but can also be made from a heat shrinkable tube such as a polyester tube. it can. The inner strain release can be secured to the most proximal end of the hypotube (eg, near the hub of the included insertion device), which can be done, for example, using an adhesive or Fused Deposition Modeling. Normally, the distal end of the medial strain release is not fixed in place. This allows reciprocal movement between the medial shaft containing multiple cavities and the medial strain release when the insertion device is placed at the bend during insertion. The lateral strain release may extend distal to the hypotube and terminate proximal to the distal end of the medial strain release. This positioning gradually changes the hardness from the hardest component of the insertion device, the hypotube, to the most flexible component, the inner shaft containing multiple cavities. The outer strain release can be made from a thermoplastic material such as Pebax®, nylon, or polyurethane, but can also be made from a heat shrinkable tube such as polyester or polyolefin tubing. By incorporating the strain release part on the inside and outside, a structure with a relatively large diameter

An example of a procedure for connecting the inflow cannula 12 to the heart 15 is shown in FIGS. 7A-7G. In this regard, the access site 300 (FIG. 7A), such as the so-called Waterson groove, is exposed during the surgical procedure or is otherwise accessed. A puncture portion 302 (FIG. 7B) can be created with a hollow needle 304 at the access site 300 of the wall 14a of the heart 15 to access the interior of the left atrium 14 and insert the distal end portion 12a of the cannula 12. .. In an alternative surgical procedure, a small incision can be made with a scalpel to access the interior of the left atrium 14 instead of the puncture 302 made with the needle 304. The diameter of the lumen of the needle 304 must be large enough for the guide wire 50 to pass through the needle 304.

FIG. 7B shows the inflow cannula and insertion device 200 being delivered closer to the heart 15 and the guide wire 50 being inserted into the left atrium 14 through the puncture site 302. The guidewire 50 is usually looped within the left atrium 14 to help avoid any damage to the heart tissue by the distal tip 50a of the guidewire 50. As shown in FIGS. 7C-7F, one or more drawstring sutures 306, 308 can be secured around the puncture site 302 in preparation for insertion of the cannula 12.

FIG. 7C shows the step of advancing the tip 220 of the insertion device 200 over the guide wire 50 across the left atrium wall 14a. The inflatable member 224 is inflated at the stage shown in FIGS. 7C-7E to temporarily releasably secure the insertion device 200 to the inflow cannula 12. The hardness of the insertion device 200 allows the surgeon to accurately deliver the insertion device 200 and inflow cannula 12 to the access site 300 with minimal damage to the heart tissue and puncture the tip 220 of the insertion device 200. You will be able to insert through. The inflatable member 224 can remain inflated until the sutures 306, 308 are tightened, as discussed later.

FIG. 7D shows the subsequent stages with the entire tip 220 of the insertion device 200, the distal end 12a of the cannula 12, and the distal fixation element 22 of the cannula 12 inserted into the left atrium 14. Depending on the procedure, the inflow cannula 12 can be inserted into the left atrium 14 so that the distal fixation element 22 and the proximal fixation element 24 are first inserted into the left atrium 14. In that case, as shown in FIG. 7D, the inflow cannula 12 is then pulled slightly proximally (towards the surgeon) to position the proximal fixation element 24 outside the left atrium 14 and the distal fixation element 22. Leave inside the left atrium 14. The materials of the fixing elements 22, 24 may be flexible and / or elastic materials, such as surgical grade silicones, or any other suitable biocompatible material. Due to the material nature of the fixation elements 22 and 24, the fixation elements 22 and 24 can shrink as they pass through the wall 14a of the heart 15 and expand to their original shape after being inserted into the left atrium 14. Can be done. Alternatively, the fixation elements 22, 24 can be expanded or contracted by any suitable mechanism operated by the surgeon. Further, proximal anchor element 24 has a smaller diameter than the distal fixation element 22, a relatively small proximal anchor main pop out element 24 through the puncture 302, the wall of the distal fixing element 22 heart 15 It can remain as a solid stop on the opposite side of 14a, giving the surgeon perceptible feedback.

At this time, as shown in FIG. 7E, the drawstring sutures 306 and 308 were tightly tightened and ligated to completely fix the tissue 310 between the distal fixation element 22 and the proximal fixation element 24, and to be liquidtight. Or at least substantially a liquidtight seal can be formed. At this point, the tightened tissue 310 must at least substantially fill or gather in the gap between the distal fixation element 22 and the proximal fixation element 24, as shown in FIG. 7E. .. If additional tissue 310 needs to be assembled, additional tissue 310 can be assembled with one or more additional drawstring sutures. Part of the cannula 12 that engages the fixing elements 22, 24, and the wall 14a can be provided with a tissue endoculture material that further aids in the formation of the anti-leakage seal.

After tightening the sutures 306, 308, pull out the guide wire 50 and insertion device 200 as shown in FIG. 7F and pull the distal end portion 12a of the cannula 12 into the left atrium 14 as shown in FIGS. 7F and 7G. Cannula 12 can be anchored to wall 14a of heart 15 by leaving it inserted in.

As mentioned earlier, co-pending U.S. Patent Application No. 11 / 846,886 entitled "Cannula Insertion Devices, Systems, and Methods Including a Compressible Member", which is expressly incorporated herein by reference in its entirety. The issue describes the sealing function of the compression member 116 of the insertion device, which favorably prevents blood loss and / or air ingress into the blood. This same function can be performed by the inflatable member 224 of the insertion device 200 disclosed herein. More specifically, when the inflatable member 224 is fully inflated, the inflatable member 224 forms a seal with the inner surface of the inflow cannula 12. Therefore, as described above with reference to FIGS. 7D and 7E, the inflatable member 224 loses blood through the inflow cannula 12 when the distal end portion 12a of the cannula 12 is inserted into the left atrium 14. The purse sutures 306 and 308 are tightened to secure the cannula 12 to the left atrial wall 14a.

Further, in the process of pulling the insertion device 200 out of the inflow cannula 12, the inflatable member 224 is partially (unlike FIG. 7F, where the inflatable member 224 is contracted and not engaged with the inner surface of the cannula 12). The insertion device 200 can be slid relative to the cannula 12 while the retractable and inflatable member 224 remains in contact with the inner surface of the cannula 12. In that case, the insertion device 200 acts like a piston that removes air. Specifically, the insertion device 200 can create a vacuum when withdrawn to draw blood from the heart 15 into the inflow cannula 12. Blood is replaced with air previously present in the inflow cannula 12.

Below, various surgical techniques are described in more detail as representative and non-limiting examples. Such techniques can be used to implement the various aspects described above herein.

<u style="single">Sternotomy</u> This technique allows full access to the heart, especially the left atrium, and allows access to several different sites where the blood influx cannula can be attached to the heart. However, because this technique is very invasive, a minimally invasive method of internal transplantation is more desirable for surgeons.

<u style="single">Thoracotomy</u> This surgical procedure provides relatively superior and caudal access by thoracotomy to deliver a blood influx cannula to a position that anchors the cannula in the left atrium. This part of the atrium is particularly beneficial because the wall of the atrium is smooth at this part and is relatively large, allowing the tip of the cannula to be separated from other structures in the atrium.

Other suitable surgical methods provide relatively lateral thoracotomy access to deliver a blood influx cannula to the left atrium and secure the inflow cannula to a site on the posterior medial wall near the atrial septum. .. This site is often referred to as the "Waterson groove" as discussed above and is a common site for left atrial incision when performing mitral valve repair surgery. The Waterson groove terminates between the superior vena cava and the left pulmonary vein in the left atrium.

<u style="single">Video-assisted thoracoscopic surgery</u> This surgical procedure uses a tubular trocar to implant a blood influx cannula into a site similar to the one above in that it accesses an intrathoracic site (eg, Waterson's groove) and anchors the cannula through the heart wall. be able to. In this minimally invasive or minimally invasive surgical procedure, the size of the patient's chest opening is minimized because the entire operation is performed by these relatively small tubular trocars. Special for making additional small holes to feed the trocars used with the main delivery trocars, endoscopic cameras, and performing gripping, cutting, suturing, cauterizing, or other operations on the tissue. Allow surgical tools to be placed. Through the main trocar, the cannula can be delivered to the same site as the open surgical technique (ie, Waterson's groove) with minimally invasive access across the chest wall.

<u style="single">Over the wire (seldinger) technique</u> A variant of the Seldinger technique can be used in the various surgical transplantation techniques described above, and the cannula system can be specially adapted to facilitate this transplantation technique. Although the Seldinger technique is usually associated with percutaneous access to blood vessels, a adapted version of the technique using a specially adapted cannulation system is highly preferred for surgical transplants with direct access to the heart. It is a method. In that case, for example, a needle can be inserted through the heart wall to make an atrial incision and then a guide wire can be placed through the needle. After removing the needle, a cannula system is introduced on the wire that controls and minimizes bleeding and has a special introduction embolus in it, thereby many of the so-called Seldinger techniques, even in surgical procedures. The benefits can be maintained.

Although the present invention has been described by the description of various exemplary embodiments and these embodiments have been described in some detail, Applicants have never limited or limited the scope of the appended claims to these details. Not intended to be. The features and embodiments discussed herein can be used in any suitable combination. Those skilled in the art will easily come up with additional benefits and changes. For example, the insertion devices disclosed in the embodiments shown herein include an inflatable member that liably secures each insertion device to the cannula, but is not an inflatable member. Alternative insertion devices having other configurations, including the expandable members of the above, can also be used according to aspects of the invention to temporarily and / or releasably secure the insertion device to their respective cannulas. An example of such an insertion device is disclosed in U.S. Patent Application No. 11 / 846,886, which is ongoing and referenced earlier, in which case the expandable member included is a compressible member 116. When compressed axially, the compressible member 116 expands radially outward to secure each insertion device to the cannula in a releasable manner. Any other suitable expansion member can be used to secure the associated insertion device to the cannula. The tip 220 can also be used with other insertion devices. For example, the tip 220 can be used with an inflatable member 224 and / or an insertion device that does not include a hub 222. The various features of the invention can be used alone or in any combination depending on the needs and preferences of the user. However, the invention itself should be defined only by the appended claims.

10 Blood circulation assist system 12 Inflow Cannula 12a Distal end 12b Proximal end 14 Left atrium 14a Left atrium wall 15 heart 16,212,214,242,246,271,272,288,290 lumens 20 patients 22 Distal fixation element 24 Proximal fixation element 30 blood pump 32 entrance 34 exit 36 Spill Cannula 40 Axillary artery 50 guide wire 50a Distal tip 200, 200a, 200b insertion device 206, 270, 280 shaft 208 Distal end 210 Proximal end 222 hub 224 Inflatable member 226, 254 hollow interior 230, 232 Tapered part 234, 236 Cylindrical part 240, 244 legs 243, 248 lure screw 247, 252 Aperture 250 syringe 274, 286 ribs 282 Inner cylindrical overhang 284 Outer cylindrical overhang 300 access site 302 Puncture 304 needle 306, 308 Drawstring suture 310 organization