Internal balloon sheath

Abstract

To provide devices and methods for providing an internal balloon sheath.SOLUTION: One device includes a sheath (400) for insertion through an arteriotomy of a patient. The sheath comprises a tubular sheath body (402) having: a longitudinal axis; an open proximal end; an open distal end; an outer surface; and an inner surface, the inner surface defining a lumen between the proximal and distal ends for passage of a catheter device. The sheath also comprises an inflatable balloon (410) disposed within the lumen. The inflatable balloon is configured to occupy a longitudinal space in the lumen between the inner surface of the sheath body and the catheter device (422) when the catheter device is disposed within the sheath and the balloon is inflated, and fluidically seal the lumen.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit under 35 U.S.C. § 119(e) of U.S. Provisional Patent Application No. 62 / 797,527, filed January 28, 2019, the entire contents of which are incorporated herein by reference. [Background technology]

[0002] background Intravascular medical devices may include, but are not limited to, Impella® pumps, extracorporeal membrane oxygenation (ECMO) pumps, and balloon pumps. Impella® pumps may further include Impella 2.5® pumps, Impella 5.0® pumps, Impella CP® pumps, and Impella LD® pumps, all from Abiomed, Inc. of Danvers, MA. The majority of intravascular medical devices are catheter devices that have a working unit, such as a pump head, at the distal end of the catheter. Such working units have a larger diameter than the catheter body that supports them. These devices often require an introducer sheath to position them in the desired location within the patient's arteriotomy before they can be activated. The introducer sheath is typically sized to allow the pump head to easily pass through the sheath without being damaged; i.e., the inner diameter of the introducer sheath is often larger than the outer diameter of the pump head.

[0003] The difference between the inner diameter of the introducer sheath and the outer diameter of the catheter body creates a space between the introducer sheath and the catheter body after the pump head is positioned from the distal end of the introducer sheath. This can lead to blood infiltration and stagnation within the sheath in the space between the introducer sheath and the catheter body, which ultimately leads to blood clotting. Clot formation between the sheath and the intravascular medical device can create multiple challenges. If a clot forms at the distal tip of the sheath, it can accidentally break free and embolize downstream (e.g., travel to the distal limb, reach the right heart and lungs, etc.). The incidence of these clinical scenarios increases when the procedure requires the device and sheath to remain in place for longer than several hours or when anticoagulation is limited.

[0004] Currently, when there is a space between the inner surface of an introducer sheath and the outer surface of an intravascular medical device catheter, physicians set up a continuous flow of saline or heparinized saline to flush through the space, often at a flow rate of, for example, 3 cc / hr. While this typically prevents clot formation, it requires additional setup and fluid delivery to the patient and carries the risk of misadministration leading to clinical complications. Because introducer sheaths and the like are not intended for long-term use, this issue has not been addressed by sheath manufacturers. In some cases, sheath manufacturers have not found a suitable technical solution, are unaware of the clinical challenge, or believe the problem should be solved by the intravascular device manufacturer.

[0005] Additionally, intravascular medical devices that straddle the aortic valve and sit within the left ventricle can be very sensitive to positioning issues. For example, if the device is positioned too far into or too far out of the heart, hemodynamic support can be compromised, potentially leading to patient harm. Long-term use of an introducer sheath with an intravascular medical device threaded through it carries the risk of the device shifting from its initial position when the patient moves. Currently, physicians attempt to secure the position of an intravascular medical device relative to the patient by connecting the proximal end of the sheath to the hub or by directly securing the distal end of the device to the outside of the patient's body (e.g., to the patient's skin with tape). This often requires additional geometries or designs that can be bulky. In some scenarios, this can be forgotten by the user, resulting in subsequent dislodgment. Summary of the Invention

[0006] overview Disclosed herein are approaches to addressing the various problems and shortcomings of the state of the art, as discussed above. More specifically, disclosed herein is a device for delivering a catheter device to an arteriotomy in a patient using a sheath with an internal balloon. In one embodiment, the sheath comprises a tubular sheath body having a longitudinal axis, an open proximal end, an open distal end, an outer surface, and an inner surface defining a lumen between the proximal and distal ends for passage of the catheter device. The sheath also comprises an inflatable balloon configured to occupy a longitudinal space within the lumen between the inner surface of the sheath body and the catheter device when the catheter device is disposed within the sheath and the balloon is inflated, and to fluidly seal the lumen.

[0007] In some embodiments, the balloon may form an interference fit between the catheter device and the inner surface of the sheath body upon inflation. In certain embodiments, the balloon may be positioned at least at the distal end of the sheath body. In other embodiments, the balloon may be positioned along the entire length of the sheath body. In further embodiments, the balloon may be attached to the inner surface of the sheath body. In some embodiments, the balloon may be attached to at least the distal end of the inner surface of the sheath body. In certain embodiments, the balloon may be attached along the entire length of the inner surface of the sheath body. In other embodiments, the balloon may be attached along at least a portion of the circumference of the sheath body. In further embodiments, the balloon may be attached along at least any of the following portions of the sheath body: about 25%, about 50%, about 75%, or about 100% of the inner circumference of the sheath body.

[0008] In some embodiments, the inner surface of the sheath body may be pre-treated to improve attachment of the balloon to the inner surface of the sheath body. In certain embodiments, the balloon may be attached to the inner surface of the sheath body via thermal bonding or solvent bonding. In other embodiments, the inner surface of the sheath body may be pre-treated via one of plasma activation and corona treatment. In further embodiments, the balloon may be inflated through an inflation opening located on the inner surface of the distal end of the sheath body. In some embodiments, the sheath body may include an inflation lumen extending from the proximal end of the sheath body to the inflation opening. In certain embodiments, the inflation lumen may be in fluid communication with the inflation opening. The inflation lumen may extend in a straight or curved manner along the length of the sheath body.

[0009] In some embodiments, the sheath may further comprise a balloon sleeve on which an inflatable balloon is mounted; the sleeve is aligned in-line with the catheter device and configured to pass through the lumen of the sheath body. The proximal end of the balloon sleeve may comprise a hemostatic valve that seals with the catheter device. In certain embodiments, the balloon sleeve may comprise an inflation lumen in fluid communication with the balloon for inflation. In other embodiments, the proximal end of the balloon sleeve may comprise an inflation port in fluid communication with the inflation lumen for inflation. In further embodiments, the proximal end of the sheath body may be coupled to an inflation port in fluid communication with the balloon for inflation. In some embodiments, the inflation lumen may be in communication with a fixed volume syringe at the proximal end of the sheath body for inflating the balloon. In certain embodiments, the balloon may be inflated with any one of water, saline, and air via the inflation port.

[0010] In some embodiments, the balloon may be positioned in-line with the catheter device. In other embodiments, the balloon may be radially symmetrical with respect to the longitudinal axis of the sheath body. In further embodiments, the balloon may be ring-shaped through which the catheter device passes. In certain embodiments, the balloon, upon inflation, may apply a radial force on the catheter device, thereby locking the catheter device in position. In some embodiments, the balloon may be asymmetrical with respect to the longitudinal axis of the sheath body. When inflated, the balloon may exert a force on the catheter device to push the catheter device toward a portion of the inner surface of the sheath body, thereby locking the catheter device in position.

[0011] In certain embodiments, the sheath body may comprise a stack of multiple polymer layers arranged coaxially around a longitudinal axis. In other embodiments, the sheath body may comprise a combination of multiple tubular polymer layer segments arranged continuously from the proximal end to the distal end of the sheath body. Each polymer layer may comprise a different polymer material type. In some embodiments, the polymer material type may include any one of PEBAX® 7233SA, PEBAX® 7033SA, PEBAX® 6333SA, PEBAX® 5533SA, PEBAX® 3533SA, and PEBAX® 2533SA.

[0012] In further embodiments, the sheath body may include a reinforcing structure to prevent kinking. In other embodiments, the reinforcing structure may include any one of a braid, a coil, and a laser-machined feature. In some embodiments, the balloon may be made from any one of urethane, polyurethane, polyethylene, polypropylene, polyethylene terephthalate (PET), polyvinyl chloride (PVC), polyethylene, cross-linked polyethylene, polyether block amide (PEBA), and nylon. In certain embodiments, the sheath body may be made from any one of polyether block amide (such as PEBAX® or PebaSlix®), polyethylene material, polytetrafluoroethylene (PTFE) material, high-density polyethylene (HDPE) material, medium-density polyethylene (MDPE) material, and low-density polyethylene (LDPE) material. In other embodiments, the distal end of the sheath body may be made from a softer, elastic material than that used for the remainder of the sheath body.

[0013] In further embodiments, the distal end of the sheath body may include a smaller diameter to provide a tight seal over the catheter device. In some embodiments, the balloon sleeve may be made from any one of urethane, polyurethane, polyethylene, polypropylene, polyethylene terephthalate (PET), polyvinyl chloride (PVC), polyethylene, cross-linked polyethylene, polyether block amide (PEBA), and nylon.

[0014] In certain embodiments, the balloon may be compliant and may remain flush against the inner surface of the sheath body upon de-inflation. In other embodiments, the balloon may be non-compliant and may not remain flush against the inner surface of the sheath body upon de-inflation. In further embodiments, the balloon may be coated with either a hydrophilic or hydrophobic coating. The coating may be of a thickness that ensures proper inflation characteristics of the balloon. In some embodiments, the sheath body may deform upon inflation of the balloon, thereby fixing the position of the sheath within the patient's arteriotomy.

[0015] In some embodiments, the proximal end of the sheath may be coupled to a hub for manipulating the sheath as it is positioned within the patient's arteriotomy. In certain embodiments, the hub may include an inflation side port in fluid communication with the fluid lumen, thereby allowing for attachment of a source of balloon inflation fluid. In other embodiments, the hub may include an irrigation port in fluid communication with the space between the catheter device and the inner surface of the sheath body, thereby allowing for flushing of the space with fluid prior to balloon inflation.

[0016] In another aspect, a sheath kit is provided. The sheath kit includes a sheath and an inflation device coupled to the sheath. The sheath includes a tubular sheath body having a longitudinal axis, an open proximal end, an open distal end, an outer surface, and an inner surface defining a lumen between the proximal and distal ends for passage of a catheter device. The sheath also includes an inflatable balloon configured to occupy a longitudinal space within the lumen between the inner surface of the sheath body and the catheter device when the catheter device is disposed within the sheath and the balloon is inflated, and to fluidly seal the lumen. The inflation device includes a fixed-volume syringe filled with a fluid for the inflatable balloon, along with the fluid.

[0017] In yet another aspect, a method of making a sheath with an internal balloon is provided. The method includes providing a tubular sheath body having a longitudinal axis, an open proximal end, an open distal end, an outer surface, and an inner surface defining a lumen between the proximal and distal ends for passage of a catheter device. The method then includes providing an inflatable balloon positioned within the lumen, the balloon configured, when inflated, to occupy a space within the lumen between the inner surface of the sheath body and the catheter device, thereby fluidly sealing the lumen.

[0018] In some embodiments, the method may further include attaching an inflatable balloon to at least a portion of the inner surface of the sheath body. In certain embodiments, the method may include pretreating the inner surface of the sheath body to improve adhesion between the balloon and the inner surface of the sheath body. In other embodiments, the pretreatment may include one of plasma activation and corona treatment. In further embodiments, the method may include providing a balloon sleeve for insertion into the lumen of the sheath body, the sleeve being in-line with the catheter device; and attaching the inflatable balloon to at least a portion of the sleeve. In some embodiments, the balloon attachment is via thermal or solvent bonding.

[0019] In further embodiments, the method may additionally include at least one of the following steps: (i) coating the surface of the balloon with either a hydrophilic coating or a hydrophobic coating; (ii) coating the surface of the balloon to a predetermined coating thickness to achieve specific inflation characteristics of the balloon; and (iii) coating the catheter-type medical device. In some embodiments, the method may further include coupling the proximal end of the sheath body to a hub.

[0020] In a further aspect, a method of using a sheath with an internal balloon to treat a patient with a catheter device is provided. The method includes positioning the sheath within an arteriotomy of the patient. The method then includes inserting the catheter device into a lumen to position a distal end of the catheter device within the arteriotomy of the patient. The method then includes flushing the space with irrigation fluid and inflating the balloon with inflation fluid to fluidically seal the lumen.

[0021] In some embodiments, the method may include inserting a balloon sleeve having an inflatable balloon mounted thereon into the lumen, the sleeve being aligned in-line with the catheter device.

[0022] In another aspect, a method of using a sheath with an internal balloon to treat a patient with a catheter device is provided. The method includes inserting a sheath having a lumen running therethrough into an arteriotomy in the patient. The method also includes inserting a catheter-type device into the lumen. The method then includes inflating a balloon within the lumen between the sheath and the catheter-type device to fluidly seal the lumen.

[0023] In some embodiments, the method may include flushing the lumen before inflating the balloon. In certain embodiments, inserting the sheath may include inserting a dilator into the lumen of the sheath to position the sheath within the arteriotomy in the patient. In some embodiments, the balloon may be attached to the sheath. In other embodiments, the method may further include inserting a balloon sleeve, on which the balloon is mounted, into the lumen of the sheath between the sheath and the catheter-based device before inflating the balloon. In further embodiments, the balloon sleeve may be tightly and coaxially arranged around the catheter-based device. [The present invention 1001] a tubular sheath body having a longitudinal axis, an open proximal end, an open distal end, an outer surface, and an inner surface defining a lumen between the proximal and distal ends for passage of a catheter device; and an inflatable balloon disposed within the lumen, when the catheter device is disposed within the sheath and the balloon is inflated, occupying a longitudinal space within the lumen between the inner surface of the sheath body and the catheter device; and to fluidly seal the lumen. an inflatable balloon; A sheath for delivering a catheter device through an arteriotomy in a patient, comprising: [The present invention 1002] Any of the preceding sheaths of the present invention, wherein the balloon, when inflated, forms an interference fit between the catheter device and the inner surface of the sheath body. [The present invention 1003] Any of the aforementioned sheaths of the present invention, wherein a balloon is positioned at least at the distal end of the sheath body. [The present invention 1004] Any of the aforementioned sheaths of the present invention, wherein the balloon is positioned along the entire length of the sheath body. [The present invention 1005] Any of the aforementioned sheaths of the present invention, wherein the balloon is attached to the inner surface of the sheath body. [The present invention 1006] The sheath of the present invention 1005, wherein the balloon is attached to at least the distal end of the inner surface of the sheath body. [The present invention 1007] The sheath of the present invention 1004, wherein the balloon is attached along the entire length of the inner surface of the sheath body. [The present invention 1008] A sheath according to any one of claims 1005 to 1007, wherein the balloon is attached along at least a portion of the circumference of the sheath body. [The present invention 1009] The sheath of any one of claims 1005 to 1008, wherein the balloon is attached along at least one of the following portions of the sheath body: about 25%, about 50%, about 75%, and about 100% of the inner circumference of the sheath body. [The present invention 1010] The sheath of any one of claims 1005 to 1009, wherein the inner surface of the sheath body is pretreated to improve attachment of the balloon to the inner surface of the sheath body. [The present invention 1011] The sheath of any one of 1005 to 1010, wherein the balloon is attached to the inner surface of the sheath body via thermal or solvent bonding. [The present invention 1012] The sheath of the present invention 1010, wherein the inner surface of the sheath body is pretreated via one of plasma activation and corona treatment. [The present invention 1013] Any of the aforementioned sheaths of the present invention, wherein the balloon is inflated through an inflation opening located on the inner surface of the distal end of the sheath body. [The present invention 1014] The sheath of the present invention 1013, wherein the sheath body comprises an inflation lumen extending from the proximal end of the sheath body to the inflation opening. [The present invention 1015] The sheath of the present invention 1014, wherein the inflation lumen is in fluid communication with the inflation opening. [The present invention 1016] The sheath of any one of 1014 to 1022, wherein the inflation lumen extends in a straight or curved manner along the length of the sheath body. [The present invention 1017] a balloon sleeve having an inflatable balloon mounted thereon, the sleeve being configured to be aligned in-line with the catheter device and to pass through the lumen of the sheath body; The sheath of any one of the present inventions 1001 to 1004 further comprises: [The present invention 1018] The sheath of the present invention 1017, wherein the proximal end of the balloon sleeve is provided with a hemostatic valve that seals with the catheter device. [The present invention 1019] A sheath according to any one of claims 1017 to 1018, wherein the balloon sleeve has an inflation lumen in fluid communication with the balloon for inflation. [The present invention 1020] The sheath of the present invention 1019, wherein the proximal end of the balloon sleeve comprises an inflation port in fluid communication with the inflation lumen for inflation. [The present invention 1021] The sheath of any of claims 1001 to 1016, wherein the proximal end of the sheath body is connected to an inflation port in fluid communication with the balloon for inflation. [The present invention 1022] A sheath according to any one of claims 1019 to 1021, wherein the inflation lumen is in communication with a fixed volume syringe at the proximal end of the sheath body for inflating the balloon. [The present invention 1023] The sheath of any one of inventions 1021 to 1022, wherein the balloon is inflated with any one of water, saline, and air via an inflation port. [The present invention 1024] Any of the aforementioned sheaths of the present invention, wherein the balloon is positioned in-line with the catheter device. [The present invention 1025] Any of the aforementioned sheaths of the present invention, wherein the balloon is radially symmetric about the longitudinal axis of the sheath body. [The present invention 1026] Any of the preceding sheaths of the present invention, wherein the balloon is ring-shaped and a catheter device passes therethrough. [The present invention 1027] Any of the preceding sheaths of the present invention, wherein the balloon, when inflated, applies a radial force on the catheter device, thereby locking the catheter device in position. [The present invention 1028] The sheath of any one of claims 1001 to 1018, wherein the balloon is asymmetric with respect to the longitudinal axis of the sheath body. [The present invention 1029] The sheath of the present invention 1028, wherein the balloon, when inflated, exerts a force on the catheter device to push the catheter device against a portion of the inner surface of the sheath body, thereby locking the catheter device in position. [The present invention 1030] Any of the aforementioned sheaths of the present invention, wherein the sheath body comprises a stack of multiple polymer layers arranged coaxially with one another about a longitudinal axis. [The present invention 1031] A sheath according to any one of claims 1001 to 1029, wherein the sheath body comprises a combination of multiple tubular polymer layer portions arranged continuously from the proximal end to the distal end of the sheath body. [The present invention 1032] The sheath of any one of claims 1030 to 1031, wherein each polymer layer comprises a different polymer material type. [The present invention 1033] The sheath of the present invention 1032, wherein the polymer material type includes any one of PEBAX® 7233SA, PEBAX® 7033SA, PEBAX® 6333SA, PEBAX® 5533SA, PEBAX® 3533SA, and PEBAX® 2533SA. [The present invention 1034] Any of the aforementioned sheaths of the present invention, wherein the sheath body comprises a reinforcing structure to prevent kinking. [This invention 1035] The sheath of the present invention 1034, wherein the reinforcing structure includes one of a braid, a coil, and a laser-machined feature. [The present invention 1036] Any of the aforementioned sheaths of the present invention, wherein the balloon is made from any one of urethane, polyurethane, polyethylene, polypropylene, polyethylene terephthalate (PET), polyvinyl chloride (PVC), polyethylene, cross-linked polyethylene, polyether block amide (PEBA), and nylon. [This invention 1037] Any of the above sheaths of the present invention, wherein the sheath body is made from any one of polyether block amide (such as PEBAX® or PebaSlix®), polyethylene material, polytetrafluoroethylene (PTFE) material, high density polyethylene (HDPE) material, medium density polyethylene (MDPE) material, and low density polyethylene (LDPE) material. [The present invention 1038] Any of the aforementioned sheaths of the present invention, wherein the distal end of the sheath body is made from a softer, resilient material than that used for the remainder of the sheath body. [This invention 1039] The sheath of the present invention 1038, wherein the distal end of the sheath body includes a smaller diameter to provide a tight seal over the catheter device. [The present invention 1040] A sheath of any of claims 1017 to 1019, wherein the balloon sleeve is made from any one of urethane, polyurethane, polyethylene, polypropylene, polyethylene terephthalate (PET), polyvinyl chloride (PVC), polyethylene, cross-linked polyethylene, polyether block amide (PEBA), and nylon. [This invention 1041] Any of the preceding sheaths of the present invention, wherein the balloon is compliant and remains flush against the inner surface of the sheath body upon de-inflation. [The present invention 1042] The sheath of the present invention 1001, wherein the balloon is non-compliant and does not remain flush against the inner surface of the sheath body upon de-inflation. [This invention 1043] Any of the aforementioned sheaths of the present invention, wherein the balloon is coated with a hydrophilic coating. [This invention 1044] A sheath according to any one of claims 1001 to 1042, wherein the balloon is coated with a hydrophobic coating. [This invention 1045] Any of the aforementioned sheaths of the present invention, wherein the coating is of a thickness that ensures proper inflation characteristics of the balloon. [The present invention 1046] Any of the sheaths of the present invention described above, wherein the sheath body deforms upon inflation of the balloon, thereby fixing the position of the sheath within the patient's arteriotomy. [This invention 1047] Any of the aforementioned sheaths of the present invention, wherein the proximal end of the sheath is coupled to a hub for manipulating the sheath while it is being positioned within the arteriotomy of a patient. [This invention 1048] The sheath of any of the present inventions 1014-1016 and 1019-1022, wherein the hub has an inflation side port in fluid communication with the fluid lumen, thereby allowing attachment of a source of fluid for balloon inflation. [This invention 1049] A sheath of any of the present inventions 1047 to 1048, wherein the hub has an irrigation port in fluid communication with the space between the catheter device and the inner surface of the sheath body, thereby allowing the space to be flushed with fluid before inflation of the balloon. [The present invention 1050] and a sheath based on any of 1001 to 1049; a fixed volume syringe filled with fluid and connected to the sheath for inflating the balloon with fluid; 1. A sheath kit for delivering a catheter device to an arteriotomy in a patient, comprising: [This invention 1051] 1. A method of making a sheath with an internal balloon, comprising the steps of: providing a tubular sheath body having a longitudinal axis, an open proximal end, an open distal end, an outer surface, and an inner surface defining a lumen between the proximal and distal ends for passage of a catheter device; and providing an inflatable balloon positioned within the lumen, the balloon configured, when inflated, to occupy a space within the lumen between an inner surface of the sheath body and the catheter device, thereby sealing the space from the arteriotomy. [This invention 1052] Attaching an inflatable balloon to at least a portion of the interior surface of the sheath body. The method of the present invention 1051 further comprising: [This invention 1053] Pre-treating the inner surface of the sheath body to improve adhesion between the balloon and the inner surface of the sheath body. Any of the methods of 1051 to 1052 of the present invention, further comprising: [This invention 1054] The method of claim 1053, wherein the pretreatment comprises one of plasma activation and corona treatment. [This invention 1055] providing a balloon sleeve for insertion into the lumen of the sheath body, the sleeve being aligned in-line with the catheter device; and attaching an inflatable balloon to at least a portion of the sleeve; The method of the present invention 1051 further comprising: [This invention 1056] The method of any of claims 1052 to 1055, wherein the balloon attachment is via thermal or solvent bonding. [This invention 1057] Coating the surface of the balloon with either a hydrophilic or hydrophobic coating. Any of the methods of 1051 to 1056 of the present invention, further comprising: [This invention 1058] coating the surface of the balloon to a predetermined coating thickness to achieve specific inflation characteristics of the balloon; The method of the present invention 1057 further comprising: [This invention 1059] Connecting the proximal end of the sheath body to the hub Any of the methods of claims 1051 to 1058, further comprising: [The present invention 1060] A method for producing a sheath with an internal balloon according to any one of the present inventions 1001 to 1049. [This invention 1061] 1. A method of using a sheath with an internal balloon to treat a patient with a catheter device, comprising: A step of positioning any one of the sheaths 1001 to 1049 of the present invention within the arteriotomy site of the patient; inserting the catheter device into the lumen to position a distal end of the catheter device within the arteriotomy of the patient; flushing the space with irrigation fluid; and Inflating the balloon with an inflation fluid to seal the space from the arteriotomy. [This invention 1062] A method of using the sheath of the present invention 1061 further comprising the steps of: Inserting a balloon sleeve having an inflatable balloon mounted thereon into the lumen, the sleeve being aligned in-line with the catheter device. [This invention 1063] A method of inserting a catheter-based device through an arteriotomy in a patient, comprising: inserting a sheath having a lumen running therethrough into the arteriotomy of the patient; inserting the catheter-type device into the lumen; and Inflating a balloon within the lumen between the sheath and the catheter-type device to fluidly seal the lumen. [The present invention 1064] The method of claim 1063, further comprising the step of flushing the lumen before inflating the balloon. [This invention 1065] The method of any of claims 1063-1064, wherein the step of inserting a sheath includes the step of inserting a dilator into the lumen of the sheath to position the sheath within the arteriotomy of the patient. [The present invention 1066] The method of any one of claims 1063 to 1065, wherein the balloon is attached to the sheath. [This invention 1067] Any of the methods of inventions 1063 to 1065, further comprising the step of inserting a balloon sleeve onto which a balloon is mounted into the lumen of the sheath between the sheath and the catheter device before inflating the balloon. [The present invention 1068] The method of claim 1067, wherein the balloon sleeve is tightly and coaxially arranged around the catheter-based device. [Brief explanation of the drawings]

[0024] These and other objects and advantages will become apparent from the following detailed description considered in conjunction with the accompanying drawings, in which like reference characters refer to like parts throughout.

[0025] [Figure 1] 1 illustrates an exemplary sheath delivery system known in the prior art that is used to deliver a catheter-based device into an arteriotomy in a patient. [Figure 2] 2 illustrates an exemplary cross section of the sheath delivery system of FIG. 1. [Figure 3] 2 illustrates fluid and clot ingress after the sheath delivery system of FIG. 1 has been inserted into a patient. [Figure 4] 1 illustrates an exemplary inner balloon sheath according to one embodiment of the present disclosure. [Figure 5]5A and 5B show an exemplary internal balloon sheath according to one embodiment of the present disclosure, in which a balloon is positioned at the distal end of the sheath, and an exemplary internal balloon sheath according to one embodiment of the present disclosure, in which a balloon is positioned along the entire length of the sheath. [Figure 6] 1 illustrates an exemplary inflation lumen and inflation port formed in the sheath body for inflating the internal balloon according to one embodiment of the present disclosure. [Figure 7] 7 shows a radial cross section of the inner balloon sheath of FIG. 6. [Figure 8] 7 shows the inner balloon sheath of FIG. 6 before inflation. [Figure 9] 9A shows a close-up view of an exemplary inner balloon sheath with an in-line balloon sleeve according to one embodiment of the present disclosure, and FIG. 9B shows the inner balloon sheath of FIG. 9A with the in-line balloon sleeve inserted within the inner balloon sheath. [Figure 10] Figure 10A shows the radial cross section of the inner balloon sheath of Figures 9A-9B before inflation, and Figure 10B shows the radial cross section of the inner balloon sheath of Figures 9A-9B after inflation. [Figure 11] 11A shows an exemplary internal balloon sheath with a non-in-line balloon sleeve according to one embodiment of the present disclosure, and FIG. 11B shows an isometric view of the proximal end of the internal balloon sheath of FIG. 11A. [Figure 12] Figure 12A shows the radial cross section of the inner balloon sheath of Figures 11A-11B before inflation, and Figure 12B shows the radial cross section of the inner balloon sheath of Figures 11A-11B after inflation. [Figure 13] 1 shows an exemplary expandable internal balloon sheath with an in-line balloon sleeve, where the balloon and sheath are specifically designed to allow for localized expansion of the sheath, according to one embodiment of the present disclosure. [Figure 14] 1 shows an exemplary flow chart of a method for making an inner balloon sheath according to one embodiment of the present disclosure. [Figure 15]1 shows an exemplary flow chart of a method of using an internal balloon sheath according to one aspect of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0026] Detailed Description Certain exemplary embodiments will be described so that the devices and methods described herein can be fully understood. While the embodiments and features described herein are particularly described for use in connection with an internal balloon sheath for use in intravascular procedures involving catheter-based ventricular assist devices, it will be understood that all components and other features outlined below may be combined with one another in any suitable manner and may be adapted and applied to other types of procedures requiring an internal balloon sheath.

[0027] The devices and methods described herein relate to an internal balloon sheath comprising a tubular sheath body and an inflatable balloon. The tubular sheath body has a longitudinal axis, an open proximal end, an open distal end, an outer surface, and an inner surface defining a lumen between the proximal and distal ends for passage of a catheter device. The inflatable balloon is disposed within the lumen and is configured to occupy a longitudinal space within the lumen between the inner surface of the sheath body and the catheter device when the catheter device is disposed within the sheath and the balloon is inflated, thereby fluidly sealing the lumen.

[0028] Such a sheath prevents fluid ingress after balloon inflation, thereby preventing blood stagnation and clotting within the sheath lumen when the sheath is positioned within the patient's vasculature. Because the lumen within the sheath is sealed from the sheath arteriotomy, there is no need to provide irrigation fluid flow through the sheath lumen, thereby simplifying the sheath delivery system. Furthermore, the inflated balloon forms an interference fit between the outer surface of the catheter device and the inner surface of the sheath, thereby securing or locking the position of the catheter device during use. This does not involve attaching it to the patient's skin surface, which is a bulky and cumbersome fixation technique. Additionally, because the inflatable balloon fills any space between the catheter body and the sheath and reasonably occupies any dimensional differences within the sheath, the internal balloon sheath of the present invention can be used with any size catheter.

[0029] In some embodiments, the internal balloon may be attached to at least a portion of the inner surface of the sheath body, where the internal balloon may be attached to the inner surface of the distal end of the sheath body. Alternatively, the internal balloon may span the entire length of the sheath body and be attached to multiple attachment points on the inner surface of the sheath body. In certain embodiments, the balloon may be an in-line radially symmetric balloon arranged coaxially with the sheath body so that a catheter device can pass through the balloon. In other embodiments, the balloon may be an asymmetric balloon. When inflated, the balloon forms an interference fit with the sheath and catheter body, whereby the balloon grips the catheter, thereby locking it in place.

[0030] In other embodiments, the internal balloon may be attached to a balloon sleeve external to the sheath body. The sleeve may be arranged to have a tight fit over the catheter on the medical device while still being slidable thereover. The sleeve may be configured to slide around the catheter and position it within the lumen of the sheath. The balloon may be attached to the outer surface of the distal end of the sleeve. Alternatively, the balloon may span the entire length of the sleeve and be attached to multiple attachment points on the outer surface of the sleeve. In certain embodiments, the balloon may be an in-line radially symmetric balloon arranged coaxially with the sleeve so that the catheter device can be threaded through the sleeve. In other embodiments, the balloon may be an asymmetric balloon. When inflated, the balloon forms an interference fit with the sheath and catheter body, gripping the catheter and thereby locking it in position. In other embodiments, the balloon sleeve is positioned parallel to the catheter on the medical device, thereby eliminating the need to thread the medical device through the balloon sleeve.

[0031] FIG. 1 illustrates a conventional sheath delivery system 100 for positioning a catheter device 140 within a patient's blood vessel. FIG. 1 depicts a sheath 120 after insertion through a patient's skin 110 and into an arteriotomy 112. The sheath 120 is positioned within a vessel, such as a femoral artery 114, through which blood flows 116. The sheath 120 facilitates insertion of the catheter device 140 into the artery 114. The catheter device 140 may comprise a ventricular assist device, such as a percutaneous pump. One example of such a percutaneous pump is the Impella 2.5™ Pump System by Abiomed, Inc. of Danvers, Massachusetts. Such pumps generally include a catheter body with a pump head (not shown) at the distal end of the catheter body and a handle (not shown) at the proximal end of the catheter body. In most situations, the pump head has a diameter larger than the diameter of the catheter body. It will be understood that although a percutaneous heart pump is described herein, any other percutaneous or intravascular medical device may be used in conjunction with the present disclosure. The proximal end of the sheath 140 may be coupled to the hub 130.

[0032] To facilitate passage of the catheter device through the sheath 100, the inner diameter d of the sheath 120 is shi is the outer diameter of the largest part of the catheter device, d catho so that it is equal to or greater than d shi ≧ d catho In the case of the Imeplla 2.5™ pump system exemplified above, the largest portion of the device is the pump head. As depicted in FIG. 2, after the pump head passes through the sheath body 120, there is a space 128 between the inner surface 126 of the sheath 120 and the outer surface of the catheter device 140. This space 128 is defined by the inner diameter d of the sheath, as shown in FIG. shi and the outer diameter of the catheter body d catboThese spaces exist due to differences in the sheath 120's internal diameter and the sheath body's internal diameter. These spaces facilitate the ingress of blood into the sheath 120 while the sheath body is still in the patient's arteriotomy. Because there may be no fluid flow within the spaces, blood stagnation is likely, resulting in the formation of blood clots 118, 119 within the spaces 128 of the sheath body 120, as shown in FIG. 3.

[0033] When such clots form, they can accidentally break free from the sheath and move freely within the vessel with the blood, potentially embolizing downstream (e.g., entering a distal limb, reaching the right heart and lungs, etc.), complicating intravascular medical procedures. Additionally, in some cases, clot formation can increase the likelihood of blocking blood flow through the vessel. Furthermore, once a clot begins to form, it can continue to grow in size and block the vessel lumen. In some cases, to minimize clot formation, the sheath delivery system is provided with a flow of irrigation fluid that is pumped into the lumen of the sheath 120. While this flow may be provided to the lumen continuously or at a predetermined frequency, such irrigation requires the use of additional control and monitoring mechanisms, thereby complicating the sheath delivery system. Furthermore, when the catheter device 140 is deployed, the proximal end of the device may be attached to the hub 130 with tape or sutures. Such fixation may not ensure that the portion of the device within the patient's arteriotomy will not move. Additionally, such external fixation can be bulky and cumbersome, and can also loosen when the patient moves.

[0034] 4 shows an enlarged view of an internal balloon sheath 400 according to one embodiment of the present disclosure. The sheath 400 is suitable for insertion into an arteriotomy of a patient, such as the femoral artery. The sheath 400 comprises a sheath body 402 having an inner surface 404 and extending along a longitudinal axis 406. The sheath body 402 comprises a lumen 408 of diameter d extending along the longitudinal axis 406. In certain embodiments, the sheath body 402 may be tubular with a circular cross-section, although the sheath body 402 may be of any shape and configuration. The sheath body 402 has an inner diameter d shi and is suitable for introducing the intravascular medical device 420 into the vasculature of a patient. As previously mentioned, the medical device 420 may be a catheter-based device such as a percutaneous pump. One example of such a percutaneous pump is the Impella 2.5™ pump system by Abiomed, Inc. of Danvers, Massachusetts. Such pumps generally include a catheter body 422 with a pump head 424 at the distal end of the catheter body. In most situations, the pump head 424 is located within the diameter d of the catheter body. catbo Larger diameter d catho It will be understood that although a percutaneous heart pump is described herein, any other percutaneous or intravascular medical device may be used in conjunction with the present disclosure.

[0035] Once the sheath 400 is properly positioned within the vessel, the medical device 420 is deployed from the distal end 403 of the sheath body 402. To allow the medical device 420 to exit the sheath 400, the inner diameter of the sheath body 402 is adjusted to be at least equal to the diameter of the pump head 424, i.e., d shi ≧ d catho However, this means that when the medical device 420 is placed in a vessel, the inner diameter d shi and the outer diameter of the catheter body d catbo This means that a difference between the two can lead to the development of spaces, which can result in the formation of blood clots as explained above.

[0036] In accordance with one embodiment of the present disclosure, an inflatable balloon 410 is positioned within the lumen 408 of the sheath body 402. In some embodiments, the balloon 410 may be positioned at the distal end 403 of the sheath body 402. In some embodiments, the balloon 410 may be positioned elsewhere along the sheath body 402. In further embodiments, the balloon 410 may extend along the entire length of the sheath body 402.

[0037] The balloon 410 is configured to be capable of assuming and transitioning between two states: a first, de-inflated state and a second, inflated state. In the first state, the balloon 410 is not in contact with the catheter body 422 of the medical device 420, while in the second state, the balloon 420 is in contact with the catheter body 433 of the medical device 420. To transition the balloon 410 from the first, de-inflated state to the second, inflated state, a fluid is supplied to the balloon 410. In some embodiments, the fluid may be air, saline, or water, for example, although any biocompatible fluid may be used to inflate the balloon 410. Such a fluid may be supplied to the balloon via a fluid lumen, which is described in more detail in the following section. When inflated, the balloon 410 reduces the diameter of the lumen 408 so that the opening in the sheath body 402 is smaller than the diameter of the catheter body 422 of the medical device 420; i.e., in the second state, d < d catbo When the balloon is inflated (with saline or water), it fills the void / space between the catheter body 422 and the sheath's inner surface 404, thereby clearing blood ingress, stagnation, and clotting. It should be noted that in use, after the catheter device is positioned within the patient's arteriotomy, the lumen 408 of the sheath 400 may first be flushed with irrigation fluid before inflation of the balloon 410. This prevents the ingress of blood that may have accumulated during positioning of the sheath 400 or catheter device.

[0038] In the second state, the inflated balloon 410 contacts the catheter body 422 of the medical device 420 and applies a compressive force to the medical device 420. Additionally, in the second state, frictional forces between the balloon 410 and the catheter body 422 along the length of the catheter-balloon interface help secure the position of the catheter body 422 relative to the sheath 400. In some embodiments (when the balloon 410 is not attached to the sheath 400, as described below), frictional forces between the balloon 410 and the inner surface 404 of the sheath body 402 along the balloon-sheath interface also help secure the position of the catheter body 422 relative to the sheath 400.

[0039] While FIG. 4 depicts an axisymmetric balloon 410, it will be appreciated that the balloon 410 may have any shape or configuration. For example, the balloon 410 may be axisymmetric (as depicted in FIG. 4) having a circular ring shape aligned about the longitudinal axis 406 of the sheath 400. In such a configuration, the balloon 410, upon inflation, exerts a radial compressive force on the catheter body 422 from all directions about the longitudinal axis 406, thereby effectively gripping and locking the catheter body 422 in position. In other embodiments, the balloon 410 may be asymmetric about the longitudinal axis 406 of the sheath 400. For example, the balloon 410 may be positioned to one side of the longitudinal axis 406 of the sheath 400. In such a configuration, the balloon 410 exerts a compressive force on the catheter body 422 from generally one direction when inflated to the second state. When this occurs, the compressive force from the balloon 410 effectively presses the catheter body 422 against the inner surface 404 of the sheath body 402, locking its position. It will be appreciated that when the balloon 410 is in the second state, the balloon 410 prevents axial or radial movement of the medical device 420, thereby locking the medical device 420 in a fixed position.

[0040] FIG. 5A illustrates an exemplary internal balloon sheath 500 according to one embodiment of the present disclosure. It will be understood that the internal balloon sheath 500 has similar features to the sheath 400 of FIG. 4 described above. The sheath 500 has a lumen for passage of an intravascular medical device, the catheter end 505 of which is shown in FIG. 5A. The sheath 500 includes a sheath body 510 having a distal end 512 and a proximal end 514. The sheath 500 also includes an inflatable balloon 515 positioned within the lumen of the sheath 500 and located at the distal end 512 of the sheath body 510. In FIG. 5A, the inflatable balloon 515 has a fixed length and does not span the entire length of the sheath body 510. In some embodiments, the balloon 515 may be positioned at other locations along the sheath body 510. Additionally, in certain embodiments of the present disclosure, as described in the following section, the balloon 515 may be attached to the inner wall of the sheath body 510. Alternatively, the balloon 510 may be positioned within the sheath 500 by inserting a balloon sleeve into the lumen of the sheath body 510, as described in the following section.

[0041] FIG. 5B illustrates another exemplary internal balloon sheath 550 according to one embodiment of the present disclosure. It will be understood that the internal balloon sheath 550 has similar features to the sheath 500 of FIG. 5A described above. The sheath 550 has a lumen for passage of an intravascular medical device, the catheter end 555 of which is shown in FIG. 5B. Like the sheath 500, the sheath 550 includes a sheath body 560 having a distal end 562 and a proximal end 564. However, in FIG. 5B, the sheath 550 includes an inflatable balloon 565 positioned within the lumen of the sheath 500, spanning the entire length of the sheath body 560. In certain embodiments of the present disclosure, the balloon 565 may be attached to the inner wall of the sheath body 560, as described in the following section. Alternatively, the balloon 560 may be positioned within the sheath 550 by inserting a balloon sleeve into the lumen of the sheath body 560, as described in the following section.

[0042] In some embodiments of the present disclosure, the balloons 510, 560 in Figures 5A and 5B may be axisymmetric. In other embodiments, the balloons 510, 560 may be asymmetric about the longitudinal axis of the sheath body.

[0043] As shown in FIG. 5A , the proximal end 514 of the sheath body 510 may be coupled to a hub 520. The hub 520 serves as a handle that the physician can grip while positioning the sheath 500 within the patient's vasculature. The hub may also include features to facilitate securing the hub to the patient's skin once the sheath 500 is positioned within the patient's vasculature. Such securement may be via sutures or tape. Additionally, the hub 520 may have at least one side port 525, 530. Each side port may be connected to flexible tubing 526, 531, as shown in FIG. 5A , and may optionally be connected to a two-way or three-way stopcock. Each side port may be in fluid communication with a lumen of the sheath body 510. In some embodiments, the side port may be in fluid communication with additional lumens within the sheath body 510, such as an inflation lumen, as described in the following section. 5A, side port 525 is in fluid communication with the lumen of sheath body 510, and side port 530 is in fluid communication with inflatable balloon 515. Side port 520 may be connected to tubing 526 to allow for flushing of the lumen of sheath body 510 with irrigation fluid prior to inflation of balloon 515.

[0044] Flushing the lumen prior to inflation of the balloon 515 removes any stagnant blood that may have collected during insertion of the sheath into the patient's arteriotomy. The side port 530 may be connected to tubing 531 so that inflation fluid can be used to inflate the balloon 515 (described below). In some embodiments, the side port 530 may be in fluid communication with the balloon 515 via a fluid lumen formed within the sheath body 510 or via internal tubing connecting a source of inflation fluid to the balloon 515. It should be noted that in the case of FIG. 5B where the balloon 565 spans the length of the sheath body 560, the proximal end of the balloon 565 may be in direct fluid communication with an inflation port on the hub, and therefore an inflation lumen need not be within the wall of the sheath body.

[0045] Once the sheath 500 and hub 520 are in position, the physician may attach a saline syringe and / or apply a vacuum to the side ports 525, 530 to deliver fluid through the side port, down the shaft of the sheath (e.g., within the wall of the sheath body, as described in the following section), and into the interior of the balloon. Once the balloon 515 is inflated, the physician may shut off the stopcock on the side port to lock the volume there.

[0046] Returning to the embodiment of FIG. 4 , the balloon 410 may be attached to the inner surface 404 of the sheath body 402 and inflated and de-inflated therefrom. Such attachment may be achieved via thermal or solvent bonding. This bonding is crucial to prevent the balloon 410 from rupturing, for example, during inflation. In certain embodiments, the inner surface 404 of the sheath body 402 may be pre-treated with plasma activation or corona treatment to improve the likelihood of the balloon 410 bonding to the sheath body 402. In some embodiments, the balloon 410 may be located at a unique position on the sheath body 402. In such embodiments, the attachment point of the balloon 410 may be localized to the balloon's position within the sheath 400. For example, for a balloon 410 positioned at the distal end 403 of the sheath body 402, the attachment point of the balloon 410 to the inner surface 404 of the sheath body 402 may be at the distal end 403 of the sheath body 402.

[0047] In other embodiments, the balloon 410 may extend along the length of the sheath body 402. In such a configuration, the balloon 410 may be attached to the inner surface 404 of the sheath body 402 along the entire length of the balloon 410. In other configurations, the balloon 410 may be attached to the inner surface 404 of the sheath body 402 only at certain points, such as the proximal and / or distal ends of the sheath body 402. In other embodiments, the balloon 410 may not be attached to the inner surface 404 of the sheath body 402. Instead, the balloon 410 may be positioned within the lumen 408 of the sheath body 402 using a balloon sleeve, as described in the following section.

[0048] As mentioned above and with respect to the embodiment depicted in FIG. 4 , in the first state, the balloon 410 is not inflated with fluid and is not in contact with the catheter body 422. In one embodiment of the present disclosure, the balloon 410 may be configured to be compliant, such that the balloon 410 sits flush and tight against a surface within the sheath 400 when in the first state. In some embodiments, this surface may be the inner wall 404 of the sheath body 402. In other embodiments, the surface to which the compliant balloon is attached may be an additional balloon sleeve (as described in more detail in the following section). A compliant balloon 410 does not have excess balloon material upon de-inflation, thus allowing for the unhindered insertion and removal of the medical device 420 within the lumen 408 of the sheath body 402. Such a compliant balloon may be easier to fabricate and process because there is no excess balloon material to manage during bonding of the balloon 410 to the inner surface 404 of the sheath body 402. When the compliant balloon 410 is inflated, pressure from the inflation fluid (which may be delivered to the balloon 410, for example, via a syringe) causes the balloon material to elastically deform, sealing the catheter body 422, thereby closing the lumen to anything (e.g., blood and clots) entering through the arteriotomy.

[0049] In other embodiments, the balloon 410 may be configured to be non-compliant, in which case the balloon is attached to a surface within the sheath 400 when in the first state. In some embodiments, this surface may be the inner wall 404 of the sheath body 402. In other embodiments, the surface to which the compliant balloon is attached may be an additional balloon sleeve (as described in more detail in the following section). The non-compliant balloon 410 sits within the lumen 408 of the sheath 400 when de-inflated (as shown in FIGS. 6-8 and described in the following section). A non-compliant balloon may be used so that a fixed volume of fluid always provides appropriate and predictable inflation characteristics. In some embodiments, a fixed-volume syringe containing inflation fluid may be provided with the sheath 400 to ensure the correct volume of fluid is provided to the balloon 410 each time it is inflated. In certain embodiments, the syringe (and optionally the fixed-volume syringe) may be provided in a sheath kit along with any of the internal balloon sheaths described in this disclosure.

[0050] It will be understood that for all internal balloon sheaths of the present disclosure, the lumen of the internal balloon sheath is flushed with irrigation fluid to remove any blood ingress that may occur when the sheath is positioned within the patient's arteriotomy. After flushing the lumen, the balloon is inflated. Inflating the balloon seals the lumen within the sheath body from the patient's arteriotomy. It will be understood throughout this disclosure that "seal" should be taken to mean substantially sealing the lumen to exclude any amount of fluid flow that may allow blood clots to form. Thus, unlike conventional introducer sheaths, the present disclosure does not require a constant flow of irrigation fluid to flush the sheath lumen during the procedure. Furthermore, because the balloon expands to seal the lumen via an interference fit with the medical device's catheter, the sheath of the present disclosure can be used with catheters of any diameter, as long as the inner diameter of the sheath body is larger than the outer diameter of the distal-most end of the catheter device.

[0051] 6 illustrates an axial cross-sectional view of the distal section of an internal balloon sheath 600 according to one embodiment of the present disclosure. Similar to the embodiments described above, the sheath 600 includes a sheath body 610 having an inner surface 615 defining a lumen 620 for passage of an intravascular medical device having a catheter body 630. An inflatable balloon 640 is positioned at the distal end 612 of the sheath body 610. The balloon 640 may be compliant or non-compliant, and may be axisymmetric or asymmetric about the longitudinal axis 605 of the sheath body 610, in a configuration as described above.

[0052] In some embodiments, the sheath 600 may also be provided with an inflation lumen 650 within the wall of the sheath body 610 for inflating a distally positioned balloon, such as balloon 640. Such inflation lumen 650 may extend from the distal end 612 of the sheath body 610 along the length of the sheath 600 to a proximal end (not shown). The proximal end of the sheath 600 may be coupled to a hub (similar to that shown in FIGS. 5A and 5B ). The inflation lumen 650 may be in fluid communication with the interior of the balloon 640 through an opening 655 (or radial lumen 655) formed in the wall of the sheath body 610 at the interface between the balloon 640 and the inner surface 615 of the sheath body 610. In some embodiments, the balloon 640 may be attached to the inner surface 615 of the sheath body 610 via thermal or solvent bonding, as also described above. These bonds are critical to preventing the balloon 640 from rupturing. In certain embodiments, sheath body 610 may include multiple lumens similar to lumen 650 for other purposes, such as for local irrigation and flushing, or to allow for the passage of a guidewire.

[0053] Figure 7 shows a cross section 700 of the sheath 600 taken about line X-X' in Figure 6, illustrating the inflation lumen 650 formed within the wall of the sheath body 610. In Figure 7, the balloon 640 is shown as a non-compliant, axisymmetric balloon, with the balloon material within the lumen 620 of the sheath body 610 when in a de-inflated state. However, as noted above, any type of balloon (compliant, non-compliant, axisymmetric, asymmetric) may be used with embodiments of the present disclosure.

[0054] Inflation fluid is provided to the inflation lumen 650 at the hub, for example, from a syringe, which forces fluid 652 into the inflation lumen 650 and through the opening 655 into the balloon 640, inflating the balloon. In embodiments of the present disclosure, the inflation fluid may include any biocompatible fluid, such as, but not limited to, air, water, and saline. As mentioned above, when inflated, the balloon 640 reduces the diameter of the lumen 620 so that the opening in the sheath body 610 is smaller than the diameter of the medical device catheter body 630. When inflated, the balloon fills the space between the catheter body 630 and the inner surface 615 of the sheath 600, thereby preventing blood ingress, stagnation, and clotting. When fully inflated, the balloon 640 contacts and exerts a compressive force on the medical device catheter body 630. Frictional forces between the balloon 640 and the catheter body 630 along the length of the catheter-balloon interface can also help secure the position of the catheter body 630 relative to the sheath 600. In some embodiments (e.g., when the balloon is not attached to the inner surface of the sheath, as described below), frictional forces between the balloon 640 and the inner surface 615 of the sheath body 610 along the balloon-sheath interface also help secure the position of the catheter body 630 relative to the sheath 600.

[0055] FIG. 8 illustrates an axial cross-section of one section of an internal balloon sheath 800 according to one embodiment of the present disclosure. Sheath 800 includes similar features to sheath 600 in FIG. 6, except that the balloon 820 in sheath 800 is positioned along the sheath body 810, rather than at the distal end as in FIG. 6. While balloon 820 is shown in FIG. 8 as being non-compliant (and in a de-inflated state), it will be understood that balloon 820 may be configured in any manner described above. Balloon 820 is attached to the inner surface 815 of sheath body 810 at locations distal and proximal to openings 835 by thermal or solvent bonding. As described with respect to sheath 600, openings 835 fluidly connect inflation lumen 830 to balloon 820 for inflating balloon 820. These bonds are critical to prevent balloon rupture. 8 may vary depending on at least (i) where balloon 820 is located along the length of sheath body 810; (ii) how the ends of balloon 820 are attached to the inner wall of sheath body 810; and (iii) the location of opening 835 relative to the length of balloon 820. In certain embodiments where the balloon spans the entire length of the sheath body, the balloon may be inflated directly from the hub without the need for an inflation lumen within the sheath body.

[0056] In some embodiments, an inflation lumen may be formed in the sheath body, as described with respect to FIGS. 6-8 , by using a mandrel during lamination and reflow of the sheath body. Because the mandrel does not blend into the layers making up the sheath body 610, it can be removed after reflow, leaving an inflation lumen for passage of inflation fluid to the balloon. Openings fluidly connecting the inflation lumen to the balloon may also be formed using a similar process, in which radially oriented mandrels are positioned within the sheath body before reflow and subsequently removed. Alternatively, the openings may be punched out of the sheath body after the inflation lumen is formed. However, it will be recognized that forming the inflation lumen and openings may involve complex processes due to the dimensions and tolerances involved.

[0057] 9A-9B illustrate an exemplary internal balloon sheath 900 according to one embodiment of the present disclosure. The internal balloon sheath 900 includes a balloon sleeve 910 and an access sheath 920, where the balloon sleeve 910 includes an in-line sleeve that is insertable into the lumen of the access sheath 920. The internal balloon sheath 900 is configured to allow a catheter-type medical device 930 to pass therethrough. The balloon sleeve 910 includes a sleeve body 912 having a lumen 911 running therethrough. The distal end of the balloon sleeve 910 may include an inflatable balloon 915. The balloon 915 may be attached to the outer surface of the distal end of the balloon sleeve 910 using any of the attachment means described above. Any type of balloon (compliant, non-compliant, axisymmetric, or asymmetric, as described above) may be used with embodiments of the present disclosure.

[0058] The proximal end of the balloon sleeve 910 may include a valve 913 that seals the lumen 911 of the balloon sleeve 910 against the ingress of external fluids. In some embodiments, the valve 913 may include, for example, a hemostatic valve. The proximal end of the balloon sleeve 910 may also include a side port 914 in fluid communication with the lumen 911 and / or the balloon 915. In certain embodiments, the side port 914 may be in fluid communication with the balloon 915 via an inflation lumen formed in the sleeve body 912, such as the inflation lumen 650 shown in FIG. 6 . The side port 914 is similar to the side ports 525, 530 discussed above with respect to FIG. 5A . In some embodiments, there may be multiple side ports on the balloon sleeve 910. Additionally, in certain embodiments, the proximal end of the side port 914 may be coupled to a connector, such as a Tuohy-Borst adapter, to prevent backflow of fluids.

[0059] In some embodiments, the balloon sleeve 910 may be axially aligned with the medical device catheter 930 such that the sleeve 910 is in-line with the catheter 930. In this configuration, the balloon sleeve 910 is coaxially arranged around the medical device catheter 930, as depicted in FIG. 9A . The balloon sleeve 910 may fit tightly around the catheter 930 while allowing the sleeve 910 to move or move along the catheter 930 and into the access sheath 920. In certain embodiments, the medical device catheter 930 may be pre-threaded through the lumen 911 of the balloon sleeve prior to use. In some embodiments, the medical device catheter may be manufactured with the balloon sleeve 910 coaxially arranged around the catheter 930.

[0060] The access sheath 920 is similar to the sheaths described above with respect to Figures 4-8. The access sheath 920 includes a sheath body 922 having a proximal end 924, a distal end 926, and a lumen 928 running between the proximal and distal ends. The proximal end 924 may be coupled to a hub 940. The hub 940 may be similar to the hub 520 depicted in Figure 5A and may have at least one side port 942 positioned thereon. The side port 942 may be in fluid communication with the lumen 928 of the access sheath 922, for example, for irrigation and flushing.

[0061] As previously mentioned, the distal end of an intravascular medical device typically has the largest diameter compared to the catheter body. The sheath body 922 is configured so that the diameter of the lumen 928 is large enough to allow the distal end of the medical device to pass through the lumen 928. Additionally, the lumen 928 may be configured to allow the balloon sleeve 910 to pass therethrough, i.e., the lumen 928 has a diameter larger than the outer diameter of the balloon sleeve 910. In certain embodiments of the present disclosure, the diameter of the lumen 928 is such that when the balloon sleeve 910 is inserted into the lumen 928 of the access sheath 920, a space 950 is created between the outer surface of the balloon sleeve body 912 and the inner surface of the sheath body 922. This space is similar to that described above with respect to FIG. 4 . In some embodiments, the axial length of the balloon sleeve 910 may be greater than the axial length of the access sleeve 920. This causes at least a portion of the proximal end of the balloon sleeve 910 to protrude from the hub 940 of the access sheath 920 when the balloon sleeve 910 is inserted into the access sheath 920. This allows for easy access to the proximal end of the balloon sleeve 910 (and the side port attached thereto), such as for inflation of the balloon 915.

[0062] FIG. 9B shows a cross section of the inner balloon sheath 900 as the balloon sleeve 910 is moved along the catheter 930 of the medical device and into the lumen 928 of the access sheath 920. The balloon sleeve 910 would be positioned within the access sheath 920 after the lumen 928 has been flushed with irrigation fluid (e.g., saline or water) via the side port 942. In FIG. 9B, the balloon 915 is shown in an inflated state. The balloon 915 may be inflated with inflation fluid provided via the side lumen 914. Although not shown in FIG. 9A, this may be via an inflation lumen formed within the balloon sleeve body 912. As mentioned above, when the balloon 915 is inflated, pressure from the inflation fluid (which may be delivered to the balloon 915, for example, via a syringe) may cause the balloon material to elastically deform, creating a seal against the catheter body 930, thereby closing the lumen to anything (e.g., blood and clots) entering through the arteriotomy. When inflated, the balloon 915 exerts a radially expanding force on the inner surface of the access sheath body 922 from all directions, thereby effectively fixing the position of the balloon sleeve 910 relative to the access sheath 920. In some embodiments, the access sheath 920 may be made of a material that deforms under the influence of such a compressive force, as described in the following section with respect to Figure 13. In addition, when inflated, the balloon 915 also exerts a radially compressive force on the catheter body 930 from all directions around the catheter, thereby effectively gripping and locking the catheter body 930 in place.

[0063] FIG. 10A shows a cross section 1000 of the in-line inner balloon sheath 900 taken along line Y-Y′ in FIG. 9B before the balloon 915 is inflated. FIG. 10A shows a balloon sleeve 910 arranged coaxially around a catheter body 930 of a medical device. As mentioned, the balloon sleeve 910 fits tightly around the catheter body 930 while being slidable over the catheter body 930. The balloon sleeve 910 is inserted into a lumen 928 of an access sheath 922. As previously mentioned, in some embodiments, the balloon sleeve 912 may include an inflation lumen that fluidly connects an inflation port 914 on the proximal end of the balloon sleeve 910 to the balloon 915 for inflating the balloon. FIG. 10A shows a space 950 between the outer surface of the balloon sleeve body 912 and the inner surface of the sheath body 922 after the balloon sleeve 910 has been inserted into the lumen 928 of the access sheath 920. Although the balloon 915 is shown as being arranged coaxially with the balloon sleeve 912, any orientation of the balloon 915 relative to the balloon sleeve body 912 may be used. For example, the balloon 915 may be positioned on at least a portion of the outer surface of the balloon sleeve body 915.

[0064] FIG. 10B shows a cross-section 1050 of the in-line inner balloon sheath 900, taken along line Y-Y′ in FIG. 9B, after the balloon 915 has been inflated. Upon inflation of the balloon 915, the balloon material may elastically deform under pressure from the inflation fluid (which may be delivered to the balloon 915, for example, via a syringe), creating a seal against the inner surface of the access sheath 922. As can be seen, upon inflation, the balloon 915 occupies a space 950, thereby preventing fluid (e.g., blood and clots) from entering the lumen 928 of the access sheath 920. As will be understood throughout this disclosure, “sealing” should be taken to mean substantially sealing the lumen to exclude any amount of fluid flow that could allow clots to form. Upon inflation, the balloon 915 exerts radial extensional forces on the inner surface of the access sheath body 922 from all directions, thereby effectively fixing the position of the balloon sleeve 910 relative to the access sheath 920. In some embodiments, the access sheath 920 may be made of a material that deforms under the influence of such compressive forces, as described in the following section with respect to Figure 13. Additionally, when inflated, the balloon 915 also exerts a radial compressive force on the catheter body 930 from all directions around the catheter, thereby effectively gripping and locking the catheter body 930 in place.

[0065] 11A-11B illustrate an exemplary inner balloon sheath 1100 according to one embodiment of the present disclosure. The inner balloon sheath 1100 comprises a balloon sleeve 1110 and an access sheath 1120. Unlike the balloon sleeve 910 in FIGS. 9A-9B, the balloon sleeve 1100 shown in FIGS. 11A-11B is not positioned in-line with the catheter of a medical device. The balloon sleeve 1100 comprises a sleeve body 1112 having a balloon 1115 located at its distal end 1113. In some embodiments, the balloon 1115 may be located at any point along the sleeve body 1112. The sleeve body 1112 may have a central lumen fluidly connected to the balloon 1115 for inflation. The balloon 1115 may be oriented in any manner relative to the balloon sleeve body 1112 used. For example, the balloons 1115 may be arranged symmetrically around the sleeve body 1112, or the balloons 1115 may be arranged asymmetrically around the sleeve body 1112. Additionally, the balloons 1115 may be attached to the outer surface of the distal end 1113 of the sleeve body 1112 using any of the attachment means described above. Any type of balloon (compliant, non-compliant, axisymmetric, asymmetric, as described above) may be used with embodiments of the present disclosure.

[0066] The proximal end of the balloon sleeve 1110 may be coupled to a sleeve hub 1116, which may be provided with at least one side port 1117. The side port 1117 may be in fluid communication with a central lumen within the sleeve body 1112 and / or the balloon 1115. As explained above, the side port may be used as an inflation port for inflating the balloon 1115 with inflation fluid after the sheath 1100 is positioned within the patient's arteriotomy. The hub 1116 may also be provided with a connector port 1118 for connecting an additional adapter, such as a Tuohy-Borst adapter, to prevent backflow of fluid.

[0067] The access sheath 1120 is similar to the access sheath 920 in FIG. 9A as described above. The access sheath 1120 includes a sheath body 1122 having a proximal end 1124, a distal end 1126, and a lumen 1128 running between the proximal and distal ends. The proximal end 1122 may be coupled to a hub 1140. The hub 1140 may be similar to the hub 520 depicted in FIG. 5A and may have at least one side port 1142 positioned thereon. The side port 1142 may be in fluid communication with the lumen 1128 of the access sheath 1120, for example, for irrigation and flushing of the lumen 1128.

[0068] The sheath body 1120 is configured so that the diameter of the lumen 1128 is large enough to allow the distal end of a medical device to pass therethrough. Additionally, the lumen 1128 is configured to allow both the balloon sleeve 1110 and the catheter body 1130 of the medical device to pass therethrough, i.e., the lumen 1128 has a diameter greater than the combined outer diameter of both the sleeve body 1112 and the catheter body 1130. In certain embodiments of the present disclosure, the diameter of the lumen 1128 is such that when both the catheter 1130 and balloon sleeve 1110 of the medical device are inserted within the lumen 1128 of the access sheath 1120, a space 1150 is created between the outer surface of the balloon sleeve body 1112, the outer surface of the catheter body 1130, and the inner surface of the sheath body 1122 (see FIG. 12A, below). This space is similar to that described above with respect to FIG. 4.

[0069] In some embodiments, the axial length of the balloon sleeve 1110 can be longer than the axial length of the access sleeve 1120, such that at least a portion of the proximal end of the balloon sleeve 1110 protrudes from the hub 1140 of the access sheath 1120 when the balloon sleeve 1110 is inserted into the access sheath 1120, as shown in FIG. 11B. This allows for easy access to the proximal end of the balloon sleeve 1110 (and any side ports attached thereto), such as for inflation of the balloon 1115.

[0070] FIG. 12A shows a cross section 1200 of the inner balloon sheath 1100, taken about line Z-Z' in FIG. 11B, before the balloon 1115 is inflated. The balloon sleeve 1110 is inserted into the lumen 1128 of the access sheath 1120 and comprises a sleeve body 1112; the sleeve body 1112 has an inflation lumen formed therethrough in fluid communication with the balloon 1115. In some embodiments, the balloon sleeve body 1112 may comprise an inflation lumen that fluidly connects an inflation port 1117 on the proximal end of the balloon sleeve 1112 to the balloon 1115 for inflating the balloon. FIG. 12A shows a space 1150 between the inner surface of the sheath body 1120, the outer surface of the catheter body 1130, and the outer surface of the balloon sleeve 1110 after the medical device and balloon sleeve 1110 have been inserted into the lumen 1128 of the access sheath 1120. Although the balloon 1115 is shown as being arranged concentrically around the balloon sleeve body 1112, any orientation of the balloon 1115 relative to the balloon sleeve body 1112 may be used. For example, the balloon 1115 may be positioned on at least a portion of the outer surface of the balloon sleeve body 1115.

[0071] FIG. 12B shows a cross section 1250 of the inner balloon sheath 1100, taken about line Z-Z′ in FIG. 11A , after the balloon 1115 has been inflated. Upon inflation of the balloon 1115, the balloon material may elastically deform under pressure from the inflation fluid (which may be delivered to the balloon 1115, for example, via a syringe), creating a seal against the catheter body 1130. As can be seen, upon inflation, the balloon 1115 occupies a space 1150, thereby preventing fluid ingress (e.g., blood and blood clots) into the lumen 1128 of the access sheath 1120. As will be understood throughout this disclosure, “sealing” should be taken to mean substantially sealing the lumen to exclude any amount of fluid flow that could allow blood clots to form. Upon inflation, the balloon 1115 exerts a radial extensional force on the inner surface of the access sheath body 1122 from all directions, thereby effectively fixing the position of the balloon sleeve 1110 relative to the access sheath 1120. Additionally, when inflated, the balloon 1115 exerts a radial compressive force on the catheter body 1130 of the medical device to press it against the inner surface of the access sheath 1120, thereby effectively gripping and locking it in position. In some embodiments, the access sheath 1120 may be made of a material that deforms under the influence of such a stretching force, as described in the following section with respect to FIG. 13 .

[0072] FIG. 13 illustrates an exemplary inner balloon sheath 1300 according to one embodiment of the present disclosure. The inner balloon sheath 1300 includes an inflatable balloon sleeve 1310 and an access sheath 1320. The balloon sleeve 1310 may be similar to the balloon sleeves 910, 1110 described above with respect to FIGS. 9-12. The sleeve 1310 includes a sleeve body 1311 having a proximal end 1312 and a distal end 1313. An inflatable balloon 1315 may be attached to the distal end 1313 on the outer surface of the sleeve body 1311. The proximal end 1312 may be coupled to a hub 1316, and the hub 1316 may be provided with an inflation port 1314. The inflation port 1314 is configured to be in fluid communication with the balloon 1315 such that input of inflation fluid at the inflation port 1314 inflates the balloon 1315. In some embodiments, the inflation port 1314 may be fluidly connected to the balloon 1315 via an inflation lumen formed in the wall of the sleeve body 1311 .

[0073] The balloons 1315 may be oriented in any manner relative to the balloon sleeve body 1311. For example, the balloons 1315 may be arranged symmetrically around the sleeve body 1311, or the balloons 1315 may be arranged asymmetrically around the sleeve body 1311. Additionally, the balloons 1315 may be attached to the outer surface of the distal end 1313 of the balloon sleeve 1310 using any of the attachment means described above. Any type of balloon (compliant, non-compliant, axisymmetric, asymmetric, as described above) may be used with embodiments of the present disclosure.

[0074] Similar to the balloon sleeve 1310, the access sheath 1320 may be similar to the access sheaths 920, 1120 described above with respect to Figures 9-12. The access sheath 1320 comprises a sheath body 1321 having a proximal end 1322, a distal end 1323, and a lumen 1324 running between the proximal and distal ends. The proximal end 1322 may be coupled to a hub 1325. The hub 1325 may have at least one side port (not shown) positioned thereon, which may be in fluid communication with the lumen 1324 of the access sheath 1320, e.g., for irrigation and flushing of the lumen.

[0075] The sheath body 1321 is sized so that the diameter of the lumen 1324 is large enough to allow the distal end of the medical device to pass therethrough. Additionally, the lumen 1324 may be configured to allow the passage of the balloon sleeve 1310. In certain embodiments of the present disclosure, the diameter of the lumen 1324 is such that when the balloon sleeve body 1311 (positioned in-line with the medical device catheter 1330) is inserted into the lumen 1324 of the access sheath 1320, there is a space between the outer surface of the balloon sleeve body 1311 and the inner surface of the sheath body 1321. While FIG. 13 depicts the balloon sleeve 1310 as being in-line with the medical device catheter 1330 (as in FIGS. 8-9), the balloon sleeve 1310 may alternatively be adjacent to the medical device catheter 1330 (as in FIGS. 10-11).

[0076] As described in the previous embodiments, when the balloon 1315 is inflated with fluid, it occupies the space between the outer surface of the balloon sleeve body 1311 and the inner surface of the sheath body 1321, thereby sealing the lumen 1324 from blood entering through the patient's arteriotomy. In the embodiment depicted in FIG. 13, the sheath body 1321 is capable of elastic deformation such that as the balloon 1315 expands in size, the expansion force from the expanding balloon 1315 also causes deformation of the sheath body 1321 adjacent to the balloon. This creates a bulge in the access sheath 1320, which prevents axial movement of the inner balloon sheath 1300 after insertion into the patient. Thus, in addition to the sutures or tape securing the position of the hub 1325 relative to the patient's skin 1305, the bulge in the access sheath 1320 upon inflation of the balloon 1315 locks the position of the sheath 1300, thereby further securing the sheath 1300 to the patient.

[0077] In all of the above-described embodiments, the sheath may comprise a rigid material. The rigid material may be a polyethylene (PE) material or a polyurethane (PU) material. In certain embodiments, the rigid material may have a modulus of elasticity of approximately 40 ksi (285 MPa). Ksi is a unit of pressure, measured in thousands of pounds per square inch. In some embodiments, the rigid material contains a radiopaque filler, such as bismuth oxychloride or barium sulfate, at a concentration of 5% to 40% by weight. In some embodiments, the rigid material may be any one of polyether block amide (e.g., PEBAX or PebaSlix®), polyethylene material, polytetrafluoroethylene (PTFE) material, high-density polyethylene (HDPE) material, medium-density polyethylene (MDPE) material, low-density polyethylene (LDPE) material, polyetheretherketone (PEEK), polyether block amide (e.g., PEBAX), and nylon. In certain embodiments, the rigid material is a crack-resistant material. In some embodiments, the rigid material may also have a low coefficient of friction. Additionally, in all of the embodiments described above, the hub may also comprise any one of the rigid materials described above. Generally, the strength of the sheath depends on the elastic modulus of the rigid material as well as the thickness of the sheath wall. Rigid materials with lower elastic modulus will require thicker walls for the resulting sheath. Conversely, rigid materials with higher elastic modulus will allow for sheaths with thinner walls.

[0078] In all of the above-described embodiments, the sheath body may comprise a coaxially layered structure, such as that described in U.S. Provisional Patent Application No. 62 / 777,598, the entire contents of which are incorporated herein by reference. Each layer of the structure may comprise a different polymer. Polymer layering improves the sheath's strength while maintaining flexibility, making it ideal for intravascular applications such as those detailed in this disclosure. The polymer may comprise any one of PEBAX® 7233SA, PEBAX® 7033SA, PEBAX® 6333SA, PEBAX® 5533SA, PEBAX® 3533SA, and PEBAX® 2533SA. In other embodiments, the sheath may comprise various compartments, each containing a different polymer, arranged sequentially. Such an arrangement may provide varying mechanical strength along the length of the sheath body. The polymer may comprise any of the rigid materials described above. In certain embodiments, the sheath body may be reinforced with braids or coils to improve mechanical strength; these structures are constructed with wires made from any one of the rigid materials described above. In some embodiments, the structure of the sheath body may be strengthened by laser machining the tubular sheath body with features that increase its strength.

[0079] Additionally, in all of the embodiments described above, the balloon may comprise a flexible material. The flexible material may comprise a polyethylene or polyurethane material having a modulus of elasticity of about 40 ksi. In some embodiments, the material may be any one of urethane, polyurethane, polyethylene, polypropylene, polyethylene terephthalate (PET), polyvinyl chloride (PVC), polyethylene, cross-linked polyethylene, polyether block amide (PEBA), and nylon. In some embodiments, the balloon sleeve may also comprise a flexible material as defined above.

[0080] Additionally, in all aspects described above, the hub may comprise a rigid material. The rigid material may be a polyethylene material or a polyurethane material having a modulus of elasticity of about 40 ksi. In some embodiments, the rigid material may be any one of a high-density polyethylene (HDPE) material, a medium-density polyethylene (MDPE) material, a low-density polyethylene (LDPE) material, polyetheretherketone (PEEK), and a polyether block amide (such as PEBAX). In certain embodiments, the rigid material is a crack-resistant material. In some embodiments, the rigid material may also be a material with a low coefficient of friction.

[0081] In all of the above-described embodiments, a coating may be applied to the balloon to reduce friction as the interventional device passes through the inner balloon sheath. In certain embodiments, the coating may be hydrophilic or hydrophobic. In some embodiments, the thickness of this coating may be varied to achieve desired inflation characteristics for the balloon. Additionally, in all of the above-described embodiments, the inner surface of the sheath may be pretreated to improve the likelihood of bonding with the balloon. Such pretreatment may include, but is not limited to, plasma activation or corona treatment. Alternatively, or in addition to the aforementioned coatings, a coating may be applied to the catheter medical device itself prior to insertion into the inner balloon sheath.

[0082] Additionally, in all of the above-described embodiments, the sheath body may additionally comprise a distal tip made of a softer material than that used in the sheath body; i.e., the distal tip may comprise a material having a lower modulus of elasticity than the material used in the sheath body. In some embodiments, the distal tip may be beveled to aid in inserting the sheath into an arteriotomy in a patient. Such a distal tip may provide a seal on a smaller diameter catheter. Providing a seal on a catheter prevents blood from entering the sheath body and clotting. In certain embodiments, the distal tip may contain a radiopaque filler, such as bismuth oxychloride or barium sulfate, at a concentration of 5% to 40% by weight.

[0083] FIG. 14 illustrates an exemplary method 1400 for fabricating an internal balloon sheath, such as any of the balloon sheaths described above, according to one embodiment of the present disclosure. Method 1400 begins at step 1410, where a sheath body is available for fabrication. The sheath body may be provided by extrusion or lamination. As described above, the sheath body has a longitudinal axis and includes an open proximal end, an open distal end, an outer surface, and an inner surface defining a lumen between the proximal and distal ends. In some embodiments, the method may include fabricating a tubular sheath. In certain embodiments, the method may include fabricating a sheath with a diameter larger than the outer diameter of the distal end of a catheter-type intravascular medical device, such as a heart pump, to allow the medical device to pass through the lumen of the sheath body.

[0084] In certain embodiments, the method may include fabricating a sheath body that may comprise a coaxially stacked layered structure. Additionally, in some embodiments, the sheath body may comprise structural reinforcement, such as a coil or braid. Such a layered and / or reinforced body structure may allow the sheath to withstand greater pushing forces, such as those encountered when positioning an inner balloon sheath within a patient's arteriotomy. In some embodiments, the structure of the sheath body may be reinforced by laser machining the tubular sheath body with features that enhance its strength. In certain embodiments, the inner surface of the sheath body may be pretreated (e.g., via plasma activation or corona treatment) to improve the likelihood of bonding with a balloon.

[0085] The method then continues to step 1420, where an inflatable balloon is provided within the sheath body. In some embodiments, the balloon is provided by extrusion or blow molding. In certain embodiments, the method includes attaching a balloon to an inner wall of the sheath body, where the balloon is within the inner diameter of the sheath body. In some embodiments, the method further includes attaching the balloon to a balloon sleeve insertable into the lumen of the sheath body. In some embodiments, the method includes attaching a balloon that extends along the entire length of the sheath body. In other embodiments, the method includes attaching a balloon that extends only along a portion of the length of the sheath body. In some embodiments, the method includes attaching a balloon only on a portion of the inner surface of the sheath body, e.g., at the distal end of the sheath body. In other embodiments, the method includes attaching a balloon to the inner surface of the sheath body (or the outer surface of the balloon sleeve) along the entire length of the balloon. Further, in some embodiments, the method includes attaching a balloon along the entire circumference of the sheath body (or balloon sleeve). In other embodiments, the method includes attaching a balloon along at least a portion of the circumference of the sheath body (or balloon sleeve).

[0086] Additionally, in some embodiments, the method includes mounting a balloon that is in-line with (i.e., radially symmetric about) a catheter body of a medical device passing through a lumen of the sheath, hi other embodiments, the method includes mounting a balloon that is radially asymmetric about a catheter body of a medical device passing through a lumen of the sheath.

[0087] FIG. 15 illustrates an exemplary method 1500 of using an internal balloon sheath, such as any of the balloon sheaths described above, according to one embodiment of the present disclosure. Method 1500 begins at step 1510, where the internal balloon sheath is positioned within an arteriotomy in a patient. As previously mentioned, any of the sheaths described above may have a tip formed on the end of the sheath body proximal to the patient. Such a tip may be beveled to aid in insertion into the patient. In some embodiments, the sheath body may have a laminated structure capable of withstanding large pushing forces, such as those used to insert the sheath into the patient, without kinking, bending, or buckling. In certain embodiments, a dilator may be inserted into the sheath lumen prior to insertion into the patient. The dilator aids in positioning the sheath in areas of the patient's body that are difficult to penetrate with the sheath alone. Once inserted, the dilator is removed from the sheath lumen.

[0088] In step 1520, a catheter-based medical device is inserted into the lumen of the sheath. The medical device is advanced within the lumen of the sheath body until it exits the distal tip of the sheath and is positioned within the patient's arteriotomy. In some embodiments, the physician may manipulate the position of the medical device by grasping a hub attached to the proximal end of the catheter body of the medical device. Once in position, the catheter hub may be coupled to the sheath hub located on the patient's exterior.

[0089] In some embodiments, the sheath may include an internal balloon attached to the inner surface of the sheath body, as described above. In other embodiments, the balloon may be located on an additional balloon sleeve slidably arranged along the catheter body of the medical device. Once the sheath is in position and the medical device is inserted into the patient's arteriotomy, the balloon sleeve may be slid into position along the catheter body. The balloon sleeve is positioned between the inner surface of the sheath body and the outer surface of the catheter body. Although omitted here for brevity, the various configurations and attachments of internal balloons to the sheath and / or balloon sleeve described above are applicable to method 1500.

[0090] As described above, a space may exist between the inner surface of the sheath body and the outer surface of the catheter body. To prevent blood stagnation and clotting during positioning of the medical device, once the medical device is positioned within the patient's arteriotomy, the method of the present invention may optionally include flushing the lumen of the sheath body (and thus the space) with an irrigation fluid, such as saline or water. Such irrigation fluid may be provided to the lumen through an irrigation side port fluidly connected to the lumen, as described above.

[0091] At step 1530, the balloon is inflated with an inflation fluid within the sheath lumen, thereby fluidly sealing the lumen and the space between the inner surface of the sheath body and the outer surface of the catheter body. As will be understood throughout this disclosure, "sealed" should be taken to mean substantially sealing the lumen to exclude any amount of fluid flow that may allow clots to form. The inflation fluid may include, for example, saline, air, or water. Such inflation fluid may be provided to the balloon through an inflation side port fluidly connected to the balloon, as described above. In some embodiments, an inflation lumen may be provided within the sheath body for delivering inflation fluid to the balloon.

[0092] When inflated, the balloon forms an interference fit with the inner surface of the sheath body and the outer surface of the catheter body, thereby also preventing axial movement of the catheter body. In this way, the balloon effectively locks the medical device in place after inflation. In certain embodiments, inflation of the balloon also causes elastic deformation of the sheath body, causing the sheath body adjacent the inflated balloon to stretch and bulge within the patient's arteriotomy. Such bulge further fixes the position of the inner balloon sheath within the patient's vasculature, thereby securely anchoring it during use of the medical device.

[0093] If desired, the different steps discussed herein may be performed in different orders and / or simultaneously with one another. Furthermore, if desired, one or more of the above-described steps may be optional or may be combined.

[0094] The foregoing is merely illustrative of the principles of the present disclosure, and the devices and methods of the present invention may be practiced in other than the described embodiments, which are presented for purposes of illustration and not limitation. It should be understood that the devices and methods disclosed herein, although illustrated for use in the manufacture of internal balloon sheaths, may also be applied to other systems in which a single diameter, sealable sheath for insertion into a patient's vasculature is required during an intravascular procedure.

[0095] Variations and modifications will occur to those skilled in the art after reviewing this disclosure. The features of the present disclosure may be implemented in any combination and subcombination (including multiple subsidiary combinations and subcombinations) with one or more other features described herein. The various features described or illustrated above, including components thereof, may be combined or integrated into other systems. Additionally, certain features may be omitted or not implemented.

[0096] Examples of changes, substitutions, and alterations are ascertainable by one skilled in the art and could be made without departing from the scope of the information disclosed herein. All references cited herein are incorporated by reference in their entirety and made a part of this application.

Claims

1. a tubular sheath body having a proximal end, a distal end, and a lumen between the proximal end and the distal end for a catheter device to pass through; and a balloon sleeve having an inflatable balloon attached thereto; the balloon sleeve is axially aligned and in-line with the catheter device and coaxially disposed around the catheter device; the balloon sleeve is configured to pass through a lumen of the tubular sheath body to fluidly seal a lumen between the tubular sheath body and the catheter device when the inflatable balloon is inflated. Introducer sheath assembly.

2. The introducer sheath assembly of claim 1 , wherein the fluid seal is configured to form a region that prevents fluid flow between the tubular sheath body and the catheter device.

3. 2. The introducer sheath assembly of claim 1, wherein the inflatable balloon is configured, upon inflation, to form an interference fit between the catheter device and the tubular sheath body, thereby preventing axial movement of the catheter device relative to the tubular sheath body.

4. 2. The introducer sheath assembly of claim 1, wherein the length of the inflatable balloon is configured such that, when the balloon sleeve is inserted into the lumen of the tubular sheath body, a proximal end of the inflatable balloon is aligned with a proximal end of the tubular sheath body and a distal end of the inflatable balloon is aligned with a distal end of the tubular sheath body.

5. 2. The introducer sheath assembly of claim 1, wherein the proximal end of the balloon sleeve is configured to remain proximal to the proximal end of the tubular sheath body when the balloon sleeve is inserted into the lumen of the tubular sheath body such that the distal end of the inflatable balloon is aligned with the distal end of the tubular sheath body.

6. 2. The introducer sheath assembly of claim 1, wherein the balloon sleeve comprises an inflation lumen extending in a straight or curved manner from a proximal end of the balloon sleeve to an inflation opening located within the inflatable balloon, the inflation lumen being in fluid communication with the inflation opening.

7. The introducer sheath assembly of claim 1 , wherein the inflatable balloon is radially symmetric about a longitudinal axis of the balloon sleeve when inflated.

8. The introducer sheath assembly of claim 1 , wherein the inflatable balloon is ring-shaped when inflated.

9. 2. The introducer sheath assembly of claim 1, wherein the inflatable balloon is configured to lock the catheter device in position relative to the tubular sheath body by applying a radial force on the catheter device upon inflation.

10. The introducer sheath assembly of claim 1 , wherein the inflatable balloon is asymmetrical relative to the longitudinal axis of the balloon sleeve when inflated.

11. 11. The introducer sheath assembly of claim 10, wherein the inflatable balloon is configured, upon inflation, to exert a force on the catheter device to urge the catheter device toward a portion of the inner surface of the tubular sheath body, thereby locking the catheter device in position relative to the tubular sheath body.

12. The introducer sheath assembly of claim 1 , wherein the distal end of the tubular sheath body comprises a resilient material that is softer than the material of the remainder of the tubular sheath body.

13. The introducer sheath assembly of claim 1 , wherein the balloon sleeve includes a hub at a proximal end of the balloon sleeve.

14. The introducer sheath assembly of claim 13 , wherein the hub comprises a hemostatic valve.

15. The introducer sheath assembly of claim 14 , wherein the hemostatic valve is configured to seal the lumen of the balloon sleeve against ingress of external fluids.

16. 14. The introducer sheath assembly of claim 13, wherein the hub comprises an irrigation port configured to be in fluid communication with a space between the catheter device and an inner surface of the balloon sleeve, thereby enabling flushing of the space with a fluid prior to inflation of the inflatable balloon.

17. The introducer sheath assembly of claim 16, wherein the irrigation port is coupled to a connector to prevent backflow of fluid.

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